Litiasis en pediatría: correlación de métodos que dependen de la recogida de orina de 24 horas con otros más sencillos que no requieren orina minutada / Renal lithiasis in pediatric patients: correlation of methods that depend on 24-h collections with simpler methods that do not require timed urine

OBJETIVOS: Los objetivos de este trabajo fueron relacionar la eliminación urinaria de los metabolitos vinculados con la litiasis renal que dependen del volumen de orina expulsada en una unidad de tiempo, con otros parámetros que se calculan midiendo la concentración de estas sustancias en sangre y en orina, entre los cuales se incluyen los cocientes urinarios, excreciones fraccionales e índices de excreción. MATERIAL Y MÉTODOS: El estudio incluyó 401 niños sanos de tres a 14 años (187 niños y 214 niñas), con una edad media de 8,78 ± 3,40. El análisis se realizó mediante el coeficiente de correlación de Pearson. RESULTADOS: Existía una muy buena correlación, entre los valores de la eliminación cuantificada en orina de 24 horas de sodio, potasio y cloro con los cocientes urinarios y las excreciones fraccionales de estos iones. Los cocientes urinarios e índices de excreción de calcio, ácido úrico, fosfato, magnesio, citrato y oxalato mostraron una excelente correlación con las determinaciones de estas sustancias en orina de 24 horas. CONCLUSIONES: Estas ecuaciones proporcionan una información muy útil en el estudio de la etiología de la litiasis renal en los niños, así como en la adherencia al tratamiento dietético. También valora la eficacia de los distintos tratamientos utilizados en estos pacientes, sin tener que recurrir a la orina minutada, que presenta grandes dificultades en pediatría

INTRODUCTION: Daily practice requires quick, simple and accessible methods to appropriately assess the urinary excretion of solutes in diagnostic or follow-up evaluations of children with renal lithiasis. OBJECTIVES: The objective of this study was to correlate urine elimination of substances related to renal lithiasis that depend on the volume of excreted urine in a unit of time with other parameters that are calculated by measuring the concentration of these substances in blood and urine, such as urinary ratios, fractional excretions and excretion rates. MATERIALS AND METHODS: The study included 401 healthy children aged 3-14 years (187 boys and 214 girls), mean age 8.78 ± 3.40 years. The analysis was carried out by Pearson's correlation coefficient. RESULTS: There was significant correlation between the elimination of sodium, potassium and chlorine in 24-hour urine sample and the urinary ratios and fractional excretions of these ions. Urinary ratios and rates of excretion of calcium, uric acid, phosphate, magnesium, citrate and oxalate were highly correlated with the determinations of these substances in 24-hour collections. CONCLUSIONS: These equations provide relevant information for the study of the etiology of renal lithiasis in children, as well as about compliance to dietary treatment. They also assess the effectiveness of the various treatments used in these patients, without having to resort to 24-hour collections, which pose a considerable challenge in the pediatric age group

Renal lithiasis in pediatric patients: correlation of methods that depend on 24-hour collections with simpler methods that do not require timed urine. / Litiasis en pediatría: correlación de métodos que dependen de la recogida de orina de 24 horas con otros más sencillos que no requieren orina minutada.

INTRODUCTION: Daily practice requires quick, simple and accessible methods to appropriately assess the urinary excretion of solutes in diagnostic or follow-up evaluations of children with renal lithiasis. OBJECTIVES: The objective of this study was to correlate urine elimination of substances related to renal lithiasis that depend on the volume of excreted urine in a unit of time with other parameters that are calculated by measuring the concentration of these substances in blood and urine, such as urinary ratios, fractional excretions and excretion rates. MATERIALS AND METHODS: The study included 401 healthy children aged 3-14 years (187 boys and 214 girls), mean age 8.78±3.40 years. The analysis was carried out by Pearson's correlation coefficient. RESULTS: There was significant correlation between the elimination of sodium, potassium and chlorine in 24-hour urine sample and the urinary ratios and fractional excretions of these ions. Urinary ratios and rates of excretion of calcium, uric acid, phosphate, magnesium, citrate and oxalate were highly correlated with the determinations of these substances in 24-hour collections. CONCLUSIONS: These equations provide relevant information for the study of the etiology of renal lithiasis in children, as well as about compliance to dietary treatment. They also assess the effectiveness of the various treatments used in these patients, without having to resort to 24-hour collections, which pose a considerable challenge in the pediatric age group.

[Risk assessment in children with lithogenic kidney stones]. / Evaluatión del perfil de riesgo litógeno en niños con litiasis renal.

OBJECTIVE: The aim of this study was to describe the lithogenic risk profile of pediatric patients with lithiasis. METHODS: We retrospectively analyzed the metabolic studies in 24-hour urine samples in 47 pediatric patients with lithiasis. Biochemical determinations were made in blood and 24-hour urine. Oxalate calcium, brushite, struvite and uric acid salt saturations were calculated. 49 healthy children were used as a control group. RESULTS: No significant differences were found in biochemical blood parameters between children with stones and the group without stones. Calciuria, uricosuria and phosphaturia, oxalate calcium, brushite and uric acid saturations were higher in lithiasic children. In the multivariate analysis, using a logistic regression model, we only found hypercalciuria as lithogenic risk factor. (OR = 1.96 p <0.002). CONCLUSIONS: Urinary metabolic abnormalities and elevated salt saturations in urine are a frequent finding in children with urolithiasis, but in our study we only found hypercalciuria as an independent risk factor for the formation of lithiasis.

Evaluación del perfil de riesgo litógeno en niños con litiasis renal / Lithogenic risk assessment in children with kidney stones

OBJETIVO: El objetivo de este trabajo fue describir el perfil de riesgo litógeno de pacientes pediátricos con litiasis, y comparar los datos obtenidos con el grupo de niños sin evidencia de litiasis renal. MATERIAL Y MÉTODOS: Se analizaron retrospectivamente los estudios metabólicos en orina de 24 horas de 47 pacientes pediátricos diagnosticados de litiasis renal. Se determinaron en sangre y en orina de 24 horas creatinina, urea, sodio, potasio, cloro, ácido úrico, calcio, fósforo, magnesio y osmolalidad. Se calculó el nivel de saturación de oxalato cálcico, brushita, estruvita y ácido úrico. Se utilizó como grupo control una cohorte de 49 niños sanos. RESULTADOS: No se encontraron diferencias significativas en los parámetros bioquímicos sanguíneos entre los niños con litiasis y el grupo sin litiasis. La calciuria, uricosuria y fosfaturia eran superiores en el grupo de las litiasis. Las saturaciones de oxalato cálcico, fosfato cálcico y ácido úrico también eran mayores en los niños con litiasis. Al realizar el análisis multivariante mediante un modelo de regresión logística sólo se encontró como factor de riesgo litógeno a la hipercalciuria. (OR= 1,96 p < 0,002). CONCLUSIONES: Es habitual el hallazgo de alteraciones metabólicas urinarias y saturaciones elevadas de distintas sales en orina en los niños con litiasis, pero sólo se confirmó el efecto independiente de la hipercalciuria como factor determinante de riesgo en la aparición de litiasis

OBJECTIVE: The aim of this study was to describe the lithogenic risk profile of pediatric patients with lithiasis. METHODS: We retrospectively analyzed the metabolic studies in 24-hour urine samples in 47 pediatric patients with lithiasis. Biochemical determinations were made in blood and 24-hour urine. Oxalate calcium, brushite, struvite and uric acid salt saturations were calculated. 49 healthy children were used as a control group. RESULTS: No significant differences were found in biochemical blood parameters between children with stones and the group without stones. Calciuria, uricosuria. and phosphaturia, oxalate calcium, brushite and uric acid saturations were higher in lithiasic children. In the multivariate analysis, using a logistic regression model, we only found hypercalciuria as lithogenic risk factor. (OR = 1.96 p >0.002). CONCLUSIONS: Urinary metabolic abnormalities and elevated salt saturations in urine are a frequent finding in children with urolithiasis, but in our study we only found hypercalciuria as an independent risk factor for the formation of lithiasis

Hiponatremia e hipofosforemia en las neumonías: ¿qué papel desempeña el riñón? / Hyponatremia and hypophosphatemia in pneumonia: what role does the kidney?

Antecedentes: La hiponatremia es una alteración electrolítica relativamente frecuente en pacientes con neumonía, cuya patogenia se relaciona con el síndrome de secreción inapropiada de hormona antidiurética. El objetivo de este estudio era describir las alteraciones hidroelectrolíticas y hormonales en niños, previamente sanos, diagnosticados de neumonía adquirida en la comunidad (NAC), y compararlas con las de los niños sanos. Material y métodos: Se llevó a cabo un estudio de casos y controles. El grupo de casos (n= 25) estuvo formado por pacientes diagnosticados de NAC según criterios de la Organización Mundial de la Salud, con una media de edad de 4,2 ± 2,4 años; ninguno había recibido fluidoterapia intravenosa. En el grupo control (n= 27) se incluyeron niños sanos, con una media de edad de 5 ± 2,6 años, autorizados a participar en el estudio. Se realizó un análisis bioquímico en sangre y en orina (en micción aislada). En el grupo de NAC se determinaron las cifras de proteína C reactiva (PCR), procalcitonina (PCT) y vasopresina (ADH). Resultados: Los valores medios séricos del sodio, aunque en rango normal, fueron significativamente menores en el grupo de casos que en el grupo control, al igual que la excreción fraccional de sodio (EFNa), cuyo valor medio fue significativamente menor que el del grupo control. No hubo relación entre la natremia, la EFNa y los niveles de ADH. Se encontró una relación significativamente negativa entre los valores de sodio y la temperatura axilar (r= -0,64; p <0,001), la PCR (r= -0,41; p <0,04) y el recuento de leucocitos (r= -0,43; p <0,01) en sangre periférica. El valor medio del fósforo sérico era significativamente inferior al del grupo control. Se encontró una relación significativa entre la fosforemia y la reabsorción tubular de fosfato, expresada mediante TP/GFR (r= 0,97; p <0,001), y la PCR (r= -0,4; p <0,04). Conclusiones: En esta serie, los pacientes con NAC muestran una clara tendencia a presentar un descenso de la natremia. Esta tendencia es de causa extrarrenal y se relaciona significativamente con el proceso inflamatorio secundario a la infección. El descenso del fósforo sanguíneo también se relaciona con la infección, y es secundaria a una pérdida excesiva de fósforo por el riñón (AU)

Introduction: Hyponatremia is a relatively common electrolyte disturbance in patients with pneumonia and its pathogenesis has been related with the syndrome of inappropriate secretion of antidiuretic hormone. The aim of this study was to describe the electrolyte and hormonal abnormalities in children diagnosed with community-acquired pneumonia (CAP) and compare them with those obtained in healthy children. Material and methods: This is a case-control study. In the case group we included patients with CAP (n= 25), according to WHO criteria. None of the patients has received intravenous fluids. The control group (n= 27) included healthy children without disease. Biochemical blood and urine (isolated urination) were determined as analytical tests. In the CAP group C-reactive protein (CRP), procalcitonin (PCT) and levels of vasopressin (ADH) were determined. Results: The serum sodium mean values and the fractional excretion of sodium (FENa) were significantly lower in the case group than in the control group, although they were both in the normal range. There was no relationship between serum sodium, FENa and ADH levels. A significantly negative relationship was found between sodium and axillary temperature (r= -0.64; p <0.001), CRP (r= -0.41; p <0.04) and the leukocyte count in peripheral blood (r= -0.43; p <0.01). The mean serum phosphorus level was significantly lower in the case group. A remarkable relationship between phosphoremia and tubular phosphate reabsorption, expressed by TP/GFR (r= 0.97; p <0.001), and CRP (r= -0.4; p <0.04) was found. Conclusions: In this series, cases with CAP show a clear tendency of decreased serum sodium. This trend has an extrarenal cause and it is significantly related to the inflammatory process secondary to the infection. Hypophosphoremia also relates to infection and is secondary to excessive loss of phosphorus by the kidney (AU)

Pielonefritis xantogranulomatosa en niños / Xanthogranulomatous pyelonephritis in children

OBJETIVO: La pielonefritis xantogranulomatosa (PX) es una enfermedad inflamatoria renal crónica poco frecuente en la población infantil que se produce por la asociación de una obstrucción del tracto urinario de larga evolución e infección crónica. Se muestran dos casos pediátricos diagnosticados de PX. MÉTODO: Uno de ellos consultó por orinas turbias. Entre los datos bioquímicos destacaba una hipergammaglobulinemia con la presencia de una banda homogénea en la fracción gamma en el proteinograma. El otro caso se detectó en una ecografía urológica efectuada durante el seguimiento de una enfermedad litiásica renal. En este paciente, encontramos que el riñón destruido por el proceso inflamatorio, estaba adherido a capsula perirrenal, ángulo esplénico del colon y colon descendente. En ambos había leucocituria y proteinuria leve-moderada. Ninguno de los niños mostraba signos clínicos de afectación del estado general y los datos analíticos de valoración de la función renal así como los indicadores de infección eran normales. RESULTADO: Todas estas anomalías desaparecieron después de la nefrectomía del riñón afectado. CONCLUSIONES: Presentamos dos casos clínicos de PX en un grupo de edad poco afectado por esta entidad con una forma de presentación inusual. Debe mantenerse un alto índice de sospecha de la misma para diagnosticarla y tratarla oportunamente, ya que el nivel de afectación renal y extrarrenal es proporcional a la extensión y duración de la enfermedad

OBJECTIVE: Xanthogranulomatous Pyelonephritis (XP) is a renal chronic inflammatory disease infrequent during childhood produced by the association of long-term urinary tract obstruction with chronic infection. We report the cases of two children diagnosed of XP. METHODS: One of them consulted for cloudy urine. Hypergammaglobulinemia with the presence of a homogeneous band in the gamma fraction of the proteinogram stood out among laboratory findings. The other case was diagnosed while performing a urologic ultrasound in the follow up of kidney stone disease. In the latter, the renal inflammation was adhered to the perirenal capsule, colonic splenic flexure and descending colon. Both presented mild proteinuria and hematuria. None of them showed clinical sings of affectation of the general status and their renal function laboratory data as well as the infection markers were normal. RESULTS: All the alterations disappeared after performing a nephrectomy of the affected kidney. CONCLUSIONS: We present two cases of XP in a group of age rarely affected by this disease that also showed an uncommon presentation for their age. A high rate of suspicion must be held to diagnose and correctly treat this disease because the grade of renal and extra renal damage is closely related with the extension and duration of the disease

La función renal y la presión arterial en la diabetes mellitus tipo 1 / Renal function and blood pressure in type 1 diabetes mellitus

Introducción: El marcador aceptado en la diabetes mellitus tipo 1, para identificar precozmente a los pacientes de alto riesgo para desarrollar una nefropatía diabética, es la detección de microalbuminuria persistente. La monitorización ambulatoria de la presión arterial (MAPA) valora las presiones arteriales de los períodos de vigilia y de sueño y mide sus variaciones circadianas. Objetivo: Mostrar las características de la función renal y los datos proporcionados por la MAPA en una cohorte de niños diabéticos dependientes de insulina derivados al hospital. Material y métodos: Se estudiaron 61 pacientes con edades comprendidas entre 6 y 17 años. A cada niño se le programó la monitorización de la presión arterial, se estimó la tasa de filtración glomerular en orina de 24 h y se realizó determinación de hemoglobina glucosilada (HbA1c), colesterol, triglicéridos, colesterol unido a las lipoproteínas de alta densidad (c-HDL) y colesterol unido a las lipoproteínas de baja densidad (LDL). Resultados: Ningún caso presentaba una microalbuminuria persistente. La función renal muestra aumento de la tasa de filtración glomerular (146,6±22ml/min/1,73 m2). En el 39% de los casos no se produjo descenso nocturno de la presión arterial sistólica (PAS), mientras que la diastólica (PAD) encontró pérdida del descenso en el 11% de la serie. Se analizaron los casos en función de la disminución o no del descenso nocturno fisiológico de la presión arterial (PA), tanto sistólica como diastólica: no había variaciones significativas entre los datos antropométricos, los valores de la hemoglobina glicosilada (HbA1c), colesterol total, triglicéridos, c-HDL, c-LDL, tasa de filtración glomerular (GFR), proteinuria y microalbuminuria en ambos grupos. Conclusión: En la diabetes mellitus tipo 1, la atenuación del descenso nocturno fisiológico de la PAS es un hallazgo frecuente. Destaca también el aumento de la tasa de filtración glomerular(AU)

Introduction: Persistent microalbuminuria is the accepted marker for early detection of a high risk of developing diabetic nephropathy in patients diagnosed with Type I Diabetes mellitus. The Ambulatory Blood Pressure Monitoring (ABPM) evaluates the circadian variations of blood pressure while awake and asleep. Objective: To show the renal function characteristics and the data provided by ABPM in a cohort of insulin dependent diabetic children referred to our hospital. Material and methods: A total of 61 patients with an age range between 6 and 17 years were studied. In each child blood pressure monitoring was arranged, the glomerular filtration rate in 24hour urine was estimated, and glycosylated haemoglobin (HbA1c), total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, was measured. Results: None of the cases showed persistent microalbuminuria. The renal function showed an increase in the glomerular filtration rate (146.6 ± 22ml/minute/1.73 m2). In 39% of the cases there was no drop in systolic blood pressure during the night, whereas 11% of the patients in our series had a decrease in diastolic pressure. The cases were analysed depending on whether or not there had been a physiological arterial or diastolic pressure drop during the night: there were no significant differences in anthropometric data, glycosylated haemoglobin (HbA1c) levels, total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, glomerular filtration rate (GFR), proteinuria and microalbuminuria between both groups. Conclusion: In Type I Diabetes Mellitus a decrease in the physiological blood pressure during the night is a frequent finding. There is also an increase in the glomerular filtration rate(AU)

[Renal function and blood pressure in type 1 diabetes mellitus]. / La función renal y la presión arterial en la diabetes mellitus tipo 1.

INTRODUCTION: Persistent microalbuminuria is the accepted marker for early detection of a high risk of developing diabetic nephropathy in patients diagnosed with Type I Diabetes mellitus. The Ambulatory Blood Pressure Monitoring (ABPM) evaluates the circadian variations of blood pressure while awake and asleep. OBJECTIVE: To show the renal function characteristics and the data provided by ABPM in a cohort of insulin dependent diabetic children referred to our hospital. MATERIAL AND METHODS: A total of 61 patients with an age range between 6 and 17 years were studied. In each child blood pressure monitoring was arranged, the glomerular filtration rate in 24 hour urine was estimated, and glycosylated haemoglobin (HbA1c), total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, was measured. RESULTS: None of the cases showed persistent microalbuminuria. The renal function showed an increase in the glomerular filtration rate (146.6 ±22 ml/minute/1.73 m(2)). In 39% of the cases there was no drop in systolic blood pressure during the night, whereas 11% of the patients in our series had a decrease in diastolic pressure. The cases were analysed depending on whether or not there had been a physiological arterial or diastolic pressure drop during the night: there were no significant differences in anthropometric data, glycosylated haemoglobin (HbA1c) levels, total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, glomerular filtration rate (GFR), proteinuria and microalbuminuria between both groups. CONCLUSION: In Type I Diabetes Mellitus a decrease in the physiological blood pressure during the night is a frequent finding. There is also an increase in the glomerular filtration rate.

Duplicaciones del tracto urinario / Urinary tract duplication

Objetivos: Revisar las características clínicas y radiológicas de las distintas formas de duplicación del tracto urinario, valorando la evolución de los casos y la incidencia de lesión en el parénquima renal. Material y métodos: Se estudió retrospectivamente a 301 niños diagnosticados de duplicación pieloureteral mediante ecografía urológica, cistografía miccional seriada (CUMS) y gammagrafía renal con tecnecio99 (DMSA). Resultados: Se clasificaron en 4 grupos. El primer grupo estaba constituido por 166 (55,1%) casos, que presentaban una duplicación pieloureteral completa sin componente obstructivo (DC). Los que presentaban una obstrucción del sistema superior, bien por presentar un uréter ectópico (UE) 19 (6,3%) o un ureterocele (UTC) 35 (11,6%) se dividieron en 2 grupos distintos. El cuarto grupo 81 (26,9%) presentaban una duplicación pieloureteral incompleta (DI). El estudio nefrourológico se realizó en 181/301 tras presentar una infección del tracto urinario; en 100/301 tras detectarse prenatalmente una hidronefrosis. En 20/301 el diagnóstico fue casual. El porcentaje de ecografías al diagnóstico con dilatación del hemirriñón superior fue significativamente superior en los UE 16/19 (84%) y en los UTC 33/35 (94%), en relación con las dilataciones del polo superior encontradas en DC 35/166 (21%) y DI 21/81 (25%).Fueron intervenidos quirúrgicamente 69/166 (41%) de las DC; 7/81 (9%) de las DI; 16/19 (84%) de los UE, y 34/35 (97%) de los UTC. Tres casos con UE y 8 con UTC requirieron una segunda intervención y 3 fueron sometidos a una tercera intervención. El 58% de los pacientes pertenecientes al grupo de DC, 87% de las DI, 29% de los UE, 5% de los UTC, no mostraron alteraciones gammagráficas. Al estudiar las duplicaciones renales no intervenidas se observa que había 98 unidades refluyentes en las DC y de 74 en las DI. La tasa de resolución espontánea de los RVU fue del 80% en la DC y del 90% en la DI (prueba de McNemar p<0,001). El tiempo medio de curación osciló entre 1 año y 5 años (media de 3 años y 3 meses). Conclusión: Los pacientes con más riesgo de presentar lesión renal son los que presentaban una duplicación con obstrucción del hemirriñón superior por inserción ectópica del uréter y especialmente por ureterocele (AU)

Objectives: Review the clinical and radiological characteristics of the different kinds of urinary tract duplications, assessing the outcome of the cases and the incidence of renal parenchymal injury. Material and methods: A retrospective study was performed including 301 children diagnosed of renal duplication by urological ultrasound, voiding cystourethrogram (VCUG) and 99-technetium renal scintigraphy (DMSA). Results: They were classified in four groups. The first consisted of 166 (55.1%) cases that had complete ureteral duplication without an obstructive component (CD). The cases that had an upper system obstruction due to an ectopic ureter (EU), 19 (6.3%), or an ureterocele (UTC), 35 (11.6%), were divided into two different groups. The fourth group 81 (26.9%) had incomplete ureteral duplication. The nephro-urological study was performed in 181/301 after a urinary tract infection; in 100/301 after a prenatal finding of hydronephrosis. It was a casual diagnosis in 20/301.The percentage upper kidney dilation in the diagnostic ultrasound was significantly higher in those with EU 16/19 (84%) and in those with UTC 33/35 (94%), compared with the upper pole dilations found in the CD 35/166 (21%) and ID 21/81 (25%).Surgery was performed in 96/166 (41%) of the CD, 7/81 of the ID, 16/19 (84%) of the EU, and 34/35 (97%) of the UTC. Three cases with EU and 8 with UTC needed a second surgery, and 3 a third one. No scintigraphy changes were observed in 58% of the patients in the CD group, 87% in the ID group, 29% in the EU group, and 5% in the UTC group. As regards the renal duplications who did not have surgery, it was found that there were 98 refluxing units in the CD, and 74 in the ID. The spontaneous resolution of the vesicoureteral reflux (VUR) was 80% in the CD, and 90% in the ID (McNemar test P<0.001). The average healing time ranged from 1 year to 5 years (Mean: 3 years and 3 months). Conclusion: The patients with higher risk of having renal injury are those who presented with a duplication with upper kidney obstruction due to ectopic insertion of the ureter, particularly due to an ureterocele (AU)

[Urinary tract duplication]. / Duplicaciones del tracto urinario.

OBJECTIVES: Review the clinical and radiological characteristics of the different kinds of urinary tract duplications, assessing the outcome of the cases and the incidence of renal parenchymal injury. MATERIAL AND METHODS: A retrospective study was performed including 301 children diagnosed of renal duplication by urological ultrasound, voiding cystourethrogram (VCUG) and 99-technetium renal scintigraphy (DMSA). RESULTS: They were classified in four groups. The first consisted of 166 (55.1%) cases that had complete ureteral duplication without an obstructive component (CD). The cases that had an upper system obstruction due to an ectopic ureter (EU), 19 (6.3%), or an ureterocele (UTC), 35 (11.6%), were divided into two different groups. The fourth group 81 (26.9%) had incomplete ureteral duplication. The nephro-urological study was performed in 181/301 after a urinary tract infection; in 100/301 after a prenatal finding of hydronephrosis. It was a casual diagnosis in 20/301. The percentage upper kidney dilation in the diagnostic ultrasound was significantly higher in those with EU 16/19 (84%) and in those with UTC 33/35 (94%), compared with the upper pole dilations found in the CD 35/166 (21%) and ID 21/81 (25%). Surgery was performed in 96/166 (41%) of the CD, 7/81 of the ID, 16/19 (84%) of the EU, and 34/35 (97%) of the UTC. Three cases with EU and 8 with UTC needed a second surgery, and 3 a third one. No scintigraphy changes were observed in 58% of the patients in the CD group, 87% in the ID group, 29% in the EU group, and 5% in the UTC group. As regards the renal duplications who did not have surgery, it was found that there were 98 refluxing units in the CD, and 74 in the ID. The spontaneous resolution of the vesicoureteral reflux (VUR) was 80% in the CD, and 90% in the ID (McNemar test P<.001). The average healing time ranged from 1 year to 5 years (Mean: 3 years and 3 months). CONCLUSION: The patients with higher risk of having renal injury are those who presented with a duplication with upper kidney obstruction due to ectopic insertion of the ureter, particularly due to an ureterocele.

Anomalías renales de posición y de fusión / Renal position and fusion anomalies

Objetivo: Analizar las anomalías renales de posición y de fusión así como la patología nefrourológica y extrarrenal asociada en una cohorte de un hospital terciario. Material y métodos: Se revisaron retrospectivamente las historias clínicas de 84 niños diagnosticados de ectopia renal (ER) y riñones en herradura (RH), desde 1999 hasta 2010. Resultados: De los 84 pacientes estudiados, el diagnóstico prenatal se estableció en 53/84 (63,09%). Fueron diagnosticadas: 35 ectopias renales simples (ERS) unilaterales, una ERS bilateral, 2 ectopias renales cruzadas (ERC) sin fusión, 17 ERC con fusión y 29 casos de RH. La edad media al diagnóstico fue 30 días (rango 0-12 meses).En las ER se encontró una incidencia de enfermedad nefrourológica asociada de 17/84 (20,23%) en el riñón ectópico (RE) y de 15/84 (17,85%) en el riñón contralateral (RC). La mayoría correspondían a reflujo vesicoureteral (RVU). Se detectaron 4 riñones con displasia renal multiquística. En 4 casos había agenesia del RC. En los RH la incidencia de enfermedad nefrourológica asociada fue 14/84 (16,66%). La anomalía urológica asociada más frecuente también fue RVU. En 21/84 (5,45%) de los pacientes presentaban una enfermedad extrarrenal, predominando las anomalías del sistema esquelético en 9/84 (10,71%), genitales en 5/84 (5,95%), cardiacas en 3/84 (3,57%) y en 1/84 digestiva (1,19%). Con malformaciones faciales nacieron 3/84 (3,57%), con enfermedad endocrina 2/84 (2,38%) y 8/84 niños (9,52%) presentaban un síndrome polimalformativo. La complicación urológica detectada más común en el seguimiento fue la ITU en 10/84 casos (11,91%). Conclusiones: La detección de un riñón ectópico o en herradura exige la búsqueda de otras anomalías nefrourológicas asociadas y de anomalías estructurales extrarrenales. La evaluación periódica evitará posibles complicaciones (AU)

Objectives: To analyse kidney position and fusion anomalies, as well as associated urinary tract and extra-renal pathologies in a cohort from a tertiary hospital. Materials and methods: The medical records of 84 children with renal ectopia (RE) and horseshoe kidney (HK) in our hospital from 1999 to 2010 were retrospectively reviewed. Results: Prenatal diagnosis was made in 53 patients (63.09%). Of the 84 patients surveyed 35 had unilateral simple renal ectopia (SRE), 1 had bilateral SRE; 2 had crossed renal ectopia (CRE) without fusion, 17 had CRE with fusion, and 29 had HK. Average age was 30 days at diagnosis (IQR: 0-12 months).In the individuals with renal ectopia (RE), the incidence of associated urinary tract pathologies was 20.23% in the ectopic kidney (EK) (17 out of 84) and 17.85% in the contralateral kidney (CK) (15 out of 84). The most frequent urological pathology was vesico-ureteral reflux (VUR), 4 individuals had multicystic dysplastic kidneys (MCDK). In 4 patients renal agenesis was detected in the CK. In patients with HK, the incidence of associated urinary tract pathologies was 16.66% (14 out of 84), and the most frequent associated urological anomaly was also VUR. Of the 84 patients 21(25.45%) had extra-renal pathology. Anomalies of the skeletal system were detected in 9/84(10.71%), genital anomalies 5/84 (5.95%), cardiac anomalies 3/84 (3.57%), and digestive disease 1/84 (1.19%). Facial malformations were noted in 3/84 patients (3.57%), endocrine disorders 2/84 (2.38%), and 8/84 children (9.52%) suffered from polymalformative syndrome. During follow-up, the most frequent complication of the urinary tract was infection, observed in 10/84 patients (11.91%). Conclusions: When renal ectopia or horseshoe kidney is detected, associated renal and urinary anomalies and structural extra-renal malformations should be evaluated. Patients need long-term follow-up and should be examined regularly for potential complications (AU)

[Renal position and fusion anomalies]. / Anomalías renales de posición y de fusión.

OBJECTIVES: To analyse kidney position and fusion anomalies, as well as associated urinary tract and extra-renal pathologies in a cohort from a tertiary hospital. MATERIALS AND METHODS: The medical records of 84 children with renal ectopia (RE) and horseshoe kidney (HK) in our hospital from 1999 to 2010 were retrospectively reviewed. RESULTS: Prenatal diagnosis was made in 53 patients (63.09%). Of the 84 patients surveyed 35 had unilateral simple renal ectopia (SRE), 1 had bilateral SRE; 2 had crossed renal ectopia (CRE) without fusion, 17 had CRE with fusion, and 29 had HK. Average age was 30 days at diagnosis (IQR: 0-12 months). In the individuals with renal ectopia (RE), the incidence of associated urinary tract pathologies was 20.23% in the ectopic kidney (EK) (17 out of 84) and 17.85% in the contralateral kidney (CK) (15 out of 84). The most frequent urological pathology was vesico-ureteral reflux (VUR), 4 individuals had multicystic dysplastic kidneys (MCDK). In 4 patients renal agenesis was detected in the CK. In patients with HK, the incidence of associated urinary tract pathologies was 16.66% (14 out of 84), and the most frequent associated urological anomaly was also VUR. Of the 84 patients 21(25.45%) had extra-renal pathology. Anomalies of the skeletal system were detected in 9/84(10.71%), genital anomalies 5/84 (5.95%), cardiac anomalies 3/84 (3.57%), and digestive disease 1/84 (1.19%). Facial malformations were noted in 3/84 patients (3.57%), endocrine disorders 2/84 (2.38%), and 8/84 children (9.52%) suffered from polymalformative syndrome. During follow-up, the most frequent complication of the urinary tract was infection, observed in 10/84 patients (11.91%). CONCLUSIONS: When renal ectopia or horseshoe kidney is detected, associated renal and urinary anomalies and structural extra-renal malformations should be evaluated. Patients need long-term follow-up and should be examined regularly for potential complications.

Hipercalcemia hipocalciúrica familiar: a propósito de una nueva mutación / Familial hypocalciuric hypercalcemia: a new mutation

La hipercalcemia hipocalciúrica familiar (FHH) es una de las causas de hipercalcemia; se hereda de forma autosómica dominante, y posee alta penetrancia. Es el resultado de una mutación inactivante en el gen del receptor sensible al calcio (CaSR). Los casos heterocigotos no suelen presentar síntomas y se diagnostican de forma incidental. Presentamos los casos de tres niñas afectas de una mutación inactivante en heterocigosis, p.Phe789 del, en el exón 7 del gen del receptor sensible al calcio (gen CASR) localizado en el cromosoma 3q21 (Ensembl ENSG00000036828). En las muestras sanguíneas se constató hipercalcemia con calcio iónico elevado, hormona paratiroidea normal o elevada, y la calciuria disminuida. Es importante establecer el diagnostico-diferencial con el hiperparatiroidismo primario. Por lo tanto, en presencia de una hipercalcemia con hormona paratiroidea elevada o normal, se debe realizar el estudio familiar y determinar la calciuria. La aparición de algún miembro afecto en la familia o la aparición de hipocalciuria es suficiente para sospechar esta entidad e indicar el análisis mutacional, para establecer el diagnóstico diferencial con el hiperparatiroidismo primario y evitar tratamientos innecesarios (AU)

Familial hypocalciuric hypercalcemia (FHH) is a cause of hypercalcemia with autosomal dominant pattern of inheritance and high penetrance. In most of the cases it can be shown to be due to an inactivating mutation on the gene coding for the calcium-sensing receptor (CaSR). Heterozygous cases usually do not present symptoms and they are diagnosed as an incidental finding. We report three affected children with an inactivating heterozygous mutation, p.Phe789del, in exon 7 of the calcium-sensing receptor gene (CASR gene), situated in chromosome 3q21 (Ensembl ENSG00000036828), which results in elevated serum calcium, normal o high level of parathyroid hormone (PTH) and reduced urinary excretion with hypocalciuria. It is very important to determine the difference between FHH and primary hyperparathyroidism. Therefore, in a mild to moderate PTH-dependent hypercalcemia we must perform a family study and determine the urinary excretion of calcium. The presence of any other affected family member or reduced urinary calcium excretion is enough to suspect FHH, and this should be confirmed by the mutational analysis of the CASR gene, in order to establish the correct diagnosis, differentiated from primary hyperparathyroidism, to avoid unnecessary investigations or operations (AU)

[Familial hypocalciuric hypercalcemia: a new mutation]. / Hipercalcemia hipocalciúrica familiar: a propósito de una nueva mutación.

Familial hypocalciuric hypercalcemia (FHH) is a cause of hypercalcemia with autosomal dominant pattern of inheritance and high penetrance. In most of the cases it can be shown to be due to an inactivating mutation on the gene coding for the calcium-sensing receptor (CaSR). Heterozygous cases usually do not present symptoms and they are diagnosed as an incidental finding. We report three affected children with an inactivating heterozygous mutation, p.Phe789del, in exon 7 of the calcium-sensing receptor gene (CASR gene), situated in chromosome 3q21 (Ensembl ENSG00000036828), which results in elevated serum calcium, normal o high level of parathyroid hormone (PTH) and reduced urinary excretion with hypocalciuria. It is very important to determine the difference between FHH and primary hyperparathyroidism. Therefore, in a mild to moderate PTH-dependent hypercalcemia we must perform a family study and determine the urinary excretion of calcium. The presence of any other affected family member or reduced urinary calcium excretion is enough to suspect FHH, and this should be confirmed by the mutational analysis of the CASR gene, in order to establish the correct diagnosis, differentiated from primary hyperparathyroidism, to avoid unnecessary investigations or operations.

Estudios por imagen en la primera infección urinaria con fiebre del lactante. ¿Es necesaria la cistografía miccional? / Imaging studies in the first urinary infection with fever in infants: is voiding cystourethrography necessary?

Introducción: En el lactante con infección del tracto urinario (ITU), no es necesaria la presencia de reflujo vesicoureteral (RVU) para que se produzca una lesión renal adquirida. Sólo los reflujos graves pueden ser un factor que favorezca su aparición. Objetivos: Valorar si en los lactantes diagnosticados por primera vez de una ITU con fiebre, una gammagrafía renal con ácido dimercaptosuccínico (DMSA) inicial normal puede ser utilizado como método de cribado para detectar los reflujos graves y sustituir a la cistouretrografía miccional seriada(CUMS). Pacientes y métodos: Hemos estudiado retrospectivamente 162 lactantes menores de 2 años controlados en nuestro hospital por haber presentado la primera manifestación de una ITU con fiebre (92 varones y 70 mujeres). En todos los casos se habían practicado, a los pocos días del diagnóstico, una ecografía renal, una DMSA y una CUMS. Resultados: De los 162 pacientes, 62 (38 %) tenían RVU, de los cuales56 (90 %) eran leves y seis (10 %), graves. El DMSA era anormal en 26 de 100 pacientes sin RVU (26 %), en 12 de56 con RVU leve (21 %) y en 6 de 6 casos de los que tenían RVU grave (100 %). La sensibilidad del DMSA para detectarlos reflujos graves era del 100 % y la especificidad del 76%.El valor predictivo positivo y el valor predictivo negativo eran del 14 y el 100 %, respectivamente. El cociente de probabilidad positivo era de 4,17 y el cociente de probabilidad negativo de 0. Conclusiones: En el lactante con una primera manifestación de una ITU, una DMSA inicial negativa hace innecesaria la realización de la CUMS (AU)

Introduction: The presence of vesicoureteral reflux (VUR) in an infant with urinary tract infection (UTI), does not necessarily lead to an acquired renal injury. Only serious reflux can be a factor in fostering its appearance. Objectives: To assess whether in infants diagnosed for the first time with a UTI with a fever, a routine initial DMSA can be used as a screening method for detecting severe reflux and replace voiding cystourethrography (VCUG). Patients and methods: We retrospectively studied 162 infants under 2 years old admitted to our hospital due to having a ITU with fever for the first time (92 males and 70 females). In all cases, arenal ultrasound, DMSA and VCUG had been performed a few days after the diagnosis. Results: Of the 162 patients, 62 (38 %) had VUR, of which 56(90 %) were mild and 6 (10 %) were severe. The DMSA was abnormal in 26/100 patients without VUR (26 %), 12/56 with mild VUR (21 %) and 6/6 of those with severe VUR (100 %). DMSA sensitivity for detecting severe reflux was 100 % and specificity was 76 %. The positive predictive value and negative predictive value was 14 % and 100 % respectively. The positive likelihood ratio was 4.17 and the negative likelihood ratio was 0. Conclusions: It is unnecessary to carry out VCUG in an infant with an initial UTI, and a negative DMSA (AU)

[Imaging studies in the first urinary infection with fever in infants: is voiding cystourethrography necessary?]. / Estudios por imagen en la primera infección urinaria con fiebre del lactante. Es necesaria la cistografía miccional?

INTRODUCTION: The presence of vesicoureteral reflux (VUR) in an infant with urinary tract infection (UTI), does not necessarily lead to an acquired renal injury. Only serious reflux can be a factor in fostering its appearance. OBJECTIVES: To assess whether in infants diagnosed for the first time with a UTI with a fever, a routine initial DMSA can be used as a screening method for detecting severe reflux and replace voiding cystourethrography (VCUG). PATIENTS AND METHODS: We retrospectively studied 162 infants under 2 years old admitted to our hospital due to having a ITU with fever for the first time (92 males and 70 females). In all cases, a renal ultrasound, DMSA and VCUG had been performed a few days after the diagnosis. RESULTS: Of the 162 patients, 62 (38 %) had VUR, of which 56 (90 %) were mild and 6 (10 %) were severe. The DMSA was abnormal in 26/100 patients without VUR (26 %), 12/56 with mild VUR (21 %) and 6/6 of those with severe VUR (100 %). DMSA sensitivity for detecting severe reflux was 100 % and specificity was 76 %. The positive predictive value and negative predictive value was 14 % and 100 % respectively. The positive likelihood ratio was 4.17 and the negative likelihood ratio was 0. CONCLUSIONS: It is unnecessary to carry out VCUG in an infant with an initial UTI, and a negative DMSA.

[Prenatal detection of primary non-refluxing megaureter. Review of our casuistics]. / Megauréter primario no refluyente detectado prenatalmente.

BACKGROUND: Most primary non-refluxing megaureters resolve spontaneously and the indications for surgery are not sufficiently well established. OBJECTIVES: To analyze the clinical features, treatment and outcome of asymptomatic primary non-refluxing megaureter. PATIENTS AND METHODS: We retrospectively studied 58 infants with primary non-refluxing megaureter. The diagnostic methods used were renal ultrasound, renal isotopic renogram, DMSA scan, and evaluation of renal function. RESULTS: The mean age at postnatal diagnosis was 24 days. The mean follow-up was 4 years. Sixty-nine percent of the patients were male. Fifty-seven percent were left megaureters and 22% were bilateral (71 affected renal units). Eleven percent of megaureters were grade I, 48% were grade II, and 41% were grade III. Only nine patients (15%) received surgical treatment. The indications for surgical treatment were severe megaureter (3/9 patients; 33%), prolonged T1/2 (3/9 patients; 33%), reduced function (1/9 patients; 11%), prolonged T1/2 plus reduced function (1/9 patients; 11%) and increased dilation (1/9 patients; 11%). The mean age at surgery was 7 months. Outcomes in the non-surgical group (85% of the patients; 60 renal units) were as follows: 90% of megaureters were corrected or improved on ultrasound scan and 10% showed no change. In the first renogram, function was low in 4/60 kidneys (7%) and T1/2 was prolonged in 3/60 (5%). Finally, all kidneys in the non-surgical group had normal function, except one, which was injured from the beginning. T1/2 was normal in all kidneys. Outcomes in the surgical group (10 megaureters) were as follows: 80% of megaureters were corrected or improved after surgical intervention and 20% showed no change. At diagnosis, 4/10 kidneys (40%) had reduced function. In the post-surgical renogram 2/10 kidneys (20%) continued to show reduced function, 1/10 kidney (10%) showed restored renal function, and 1/10 kidney (10%) was nephrectomized. Initial T1/2 was prolonged in 4/10 patients (40%), and after surgery T1/2 was normal in all patients. The final DMSA scan showed 5/71 kidneys (7%) with irreversible damage (one slightly injured, two moderately injured, and three severely injured). The remaining 66 kidneys were normal. Overall renal function and blood pressure were normal in all patients. CONCLUSIONS: Primary non-refluxing megaureter is usually a functional and benign congenital malformation that resolves during the first months of life. Although the malformation can persist, only a few patients require surgical treatment. Most authors agree that initial treatment should not be surgical and that surgery should be reserved for patients who develop ureteral dilation, a decrease in differential renal function, and/or severe symptoms during follow-up. In a few patients (7% of our series), the renal unit belonging to the megaureter shows irreversible congenital injury. In these patients, surgery is not useful.

Megauréter primario no refluyente detectado prenatalmente / Prenatal detection of primary non-refluxing megaureter

Antecedentes Aunque la mayoría de los megauréteres primarios no refluyentes se solucionan espontáneamente, las indicaciones de cirugía no están bien establecidas. Objetivos Analizar las características clínicas, el tratamiento y la evolución del megauréter primario no refluyente asintomático. Pacientes y métodos Estudio retrospectivo de 58 lactantes con megauréter primario no refluyente. Técnicas diagnósticas utilizadas: la ecografía, el renograma, el 99Tc-ácido dimercaptosuccínico (DMSA) y la función renal. Resultados La edad media al diagnóstico posnatal era de 24 días y tiempo medio (T1/2) de seguimiento de 4 años. El 69 % de los pacientes eran varones. El 57 % de los megauréteres eran izquierdos y el 22 % bilaterales (71 unidades renales afectadas). El 11 % de los megauréteres eran grado I, el 48 % grado II y el 41 % grado III. El 15 % (9 pacientes) recibieron tratamiento quirúrgico y el 85 % restante (49 pacientes) no precisaron intervención. Las indicaciones quirúrgicas fueron: megauréter muy severo (3/9 pacientes; 33 %), T1/2 alargado (3/9 pacientes; 33 %), función disminuida (1/9 pacientes; 11 %), T1/2 alargado 1 función disminuida (1/9 pacientes; 11 %) y aumento dilatación (1/9 pacientes; 11 %). La edad media a la intervención fue de 7 meses. La evolución de los megauréteres del grupo no quirúrgico (60 unidades renales) fue la siguiente: 90 % se corrigieron-mejoraron en la ecografía y 10 % no sufrieron cambios. La función en el renograma inicial estaba disminuida en 4/60 riñones (7 %) y el T1/2 alargado en 3/60 (5 %). Al final todos los riñones del grupo no quirúrgico tenían una función normal salvo un caso lesionado desde el principio y el T1/2 se normalizó en todos. La evolución de los megauréteres del grupo quirúrgico (10 megauréteres) fue la siguiente: 80 % se corrigieron-mejoraron tras la intervención y el 20 % se mantuvieron sin cambios. Antes de la intervención había 4/10 riñones (40 %) con función disminuida. En el renograma postintervención, 2/10 (20 %) mantuvieron la función disminuida, 1/10 (10 %) la normalizó y 1/10 (10 %) fue nefrectomizado y no tenía renograma. El T1/2 inicial estaba alargado en 4/10 casos (40 %). Tras la intervención se normalizó en todos. El DMSA final mostró 5/71 riñones (7 %) con lesión irreversible (1 leve, 2 moderadas y 2 casos con lesión grave). Los 66 riñones restantes eran normales. La función renal global y presión arterial eran normales en todos los casos. Conclusiones El megauréter primario no refluyente es casi siempre funcional y benigno, normalizándose en los primeros meses de la vida. Aunque en algunos casos puede persistir, son muy pocos los pacientes que necesitan ser intervenidos. La mayoría de los autores consideran que el tratamiento inicial debe ser no quirúrgico, reservando la intervención para aquellos casos en los que durante el seguimiento se produzca un aumento de la dilatación ureteral, un deterioro de la función renal diferencial y/o aparezca sintomatología importante. En un grupo muy reducido de pacientes (7 % de nuestra serie) la unidad renal perteneciente al megauréter, puede presentar una lesión renal irreversible que la mayoría de las veces tiene un origen congénito y que por tanto no se beneficia de una intervención quirúrgica

Background Most primary non-refluxing megaureters resolve spontaneously and the indications for surgery are not sufficiently well established. Objectives To analyze the clinical features, treatment and outcome of asymptomatic primary non-refluxing megaureter. Patients and methods We retrospectively studied 58 infants with primary non-refluxing megaureter. The diagnostic methods used were renal ultrasound, renal isotopic renogram, DMSA scan, and evaluation of renal function. Results The mean age at postnatal diagnosis was 24 days. The mean follow-up was 4 years. Sixty-nine percent of the patients were male. Fifty-seven percent were left megaureters and 22 % were bilateral (71 affected renal units). Eleven percent of megaureters were grade I, 48 % were grade II, and 41 % were grade III. Only nine patients (15 %) received surgical treatment. The indications for surgical treatment were severe megaureter (3/9 patients; 33 %), prolonged T1/2 (3/9 patients; 33 %), reduced function (1/9 patients; 11 %), prolonged T1/2 plus reduced function (1/9 patients; 11 %) and increased dilation (1/9 patients; 11 %). The mean age at surgery was 7 months. Outcomes in the non-surgical group (85 % of the patients; 60 renal units) were as follows: 90 % of megaureters were corrected or improved on ultrasound scan and 10 % showed no change. In the first renogram, function was low in 4/60 kidneys (7 %) and T1/2 was prolonged in 3/60 (5 %). Finally, all kidneys in the non-surgical group had normal function, except one, which was injured from the beginning. T1/2 was normal in all kidneys. Outcomes in the surgical group (10 megaureters) were as follows: 80 % of megaureters were corrected or improved after surgical intervention and 20 % showed no change. At diagnosis, 4/10 kidneys (40 %) had reduced function. In the post-surgical renogram 2/10 kidneys (20 %) continued to show reduced function, 1/10 kidney (10 %) showed restored renal function, and 1/10 kidney (10 %) was nephrectomized. Initial T1/2 was prolonged in 4/10 patients (40 %), and after surgery T1/2 was normal in all patients. The final DMSA scan showed 5/71 kidneys (7 %) with irreversible damage (one slightly injured, two moderately injured, and three severely injured). The remaining 66 kidneys were normal. Overall renal function and blood pressure were normal in all patients. Conclusions Primary non-refluxing megaureter is usually a functional and benign congenital malformation that resolves during the first months of life. Although the malformation can persist, only a few patients require surgical treatment. Most authors agree that initial treatment should not be surgical and that surgery should be reserved for patients who develop ureteral dilation, a decrease in differential renal function, and/or severe symptoms during follow-up. In a few patients (7 % of our series), the renal unit belonging to the megaureter shows irreversible congenital injury. In these patients, surgery is not useful

[Incomplete hemolytic uremic syndrome associated with partial factor H deficiency]. / Síndrome hemolítico urémico incompleto asociado a déficit parcial de factor H.

Hemolytic uremic syndrome (HUS) consists of the association of hemolytic anemia, thrombocytopenia and renal failure. Most cases are related to toxins (verotoxins) produced by Escherichia coli 0157:H7 and generally have good renal prognosis. Atypical forms can occur, with a less favorable prognosis, and can be due to mutations in the gene codifying factor H, a protein that regulates activation of the alternative complement pathway, among other causes. Factor H deficiency produces continuous complement activation, causing injury to capillary endothelial cells. We report a case of incomplete (absence of thrombocytopenia and uremia), atypical HUS in which hypocomplementemia secondary to partial factor H deficiency was detected, with favorable outcome. Prior to symptom onset, the patient had a Campylobacter infection, precipitating the symptoms. Genetic analysis showed a heterozygous mutation (C846T) located in the SCR4 domain, generating an amino acid change in the factor H molecule (Pro240Leu). This mutation may have been the cause of the partial factor H deficiency and the patient's symptoms on admission.

Síndrome hemolítico urémico incompleto asociado a déficit parcial de factor H / Incomplete hemolytic uremic syndrome associated with partial factor H deficiency

El síndrome hemolítico urémico (SHU) asocia anemia hemolítica, trombocitopenia e insuficiencia renal. La mayoría de los casos están relacionados con las toxinas (verotoxinas) producidas por Escherichia coli 0157:H7 y generalmente tienen un buen pronóstico renal. Existen formas atípicas, con peor pronóstico, que pueden ser secundarias, entre otras causas, a mutaciones en el gen codificador del factor H, proteína que regula la activación de la vía alternativa del complemento. Su déficit, produce una activación continua del complemento, dañando las células endoteliales de los capilares. Presentamos un caso clínico de SHU incompleto (ausencia de plaquetopenia y uremia) y atípico en el que se detectó una hipocomplementemia secundaria a un déficit parcial de factor H, cuya evolución fue favorable. Previo al inicio de los síntomas, el paciente presentó una infección por Campylobacter que actuó como agente precipitante del cuadro. El análisis genético demostró una mutación en heterocigosis (C846T) localizada en el dominio SCR4 que genera un cambio de aminoácido en la molécula del factor H (Pro240Leu). Es posible que dicha mutación haya sido la causante del déficit parcial del factor H y del cuadro que presentó al ingreso

Hemolytic uremic syndrome (HUS) consists of the association of hemolytic anemia, thrombocytopenia and renal failure. Most cases are related to toxins (verotoxins) produced by Escherichia coli 0157:H7 and generally have good renal prognosis. Atypical forms can occur, with a less favorable prognosis, and can be due to mutations in the gene codifying factor H, a protein that regulates activation of the alternative complement pathway, among other causes. Factor H deficiency produces continuous complement activation, causing injury to capillary endothelial cells. We report a case of incomplete (absence of thrombocytopenia and uremia), atypical HUS in which hypocomplementemia secondary to partial factor H deficiency was detected, with favorable outcome. Prior to symptom onset, the patient had a Campylobacter infection, precipitating the symptoms. Genetic analysis showed a heterozygous mutation (C846T) located in the SCR4 domain, generating an amino acid change in the factor H molecule (Pro240Leu). This mutation may have been the cause of the partial factor H deficiency and the patient's symptoms on admission