Risk factors for recurrence in pediatric urinary stone disease.

BACKGROUND: Children's urinary system stones may develop from environmental, metabolic, anatomical, and other causes. Our objective is to determine the recurrence and prognosis, demographic, clinical, and etiological characteristics of children with urolithiasis. METHODS: Medical records of patients were evaluated retrospectively. Patients' demographic data and medical history, serum/urine biochemical and metabolic analysis, blood gas analysis, stone analysis, imaging findings, and medical/surgical treatments were recorded. RESULTS: The study included 364 patients (male 187). Median age at diagnosis was 2.83 (IQR 0.83-8.08) years. The most common complaints were urinary tract infection (23%) and urine discoloration (12%). Sixty-two percent had a family history of stone disease. At least one metabolic disorder was found in 120 (88%) of 137 patients having all metabolic analyses: hypercalciuria was found in 45%, hypocitraturia in 39%, and hyperoxaluria in 37%. Anatomical abnormalities were detected in 18% of patients. Of 58 stones analyzed, 65.5% were calcium and 20.6% were cystine stones. Stone recurrence rate was 15% (55/364). Older age (> 5 years), family history of stone disease, stone size (≥ 5 mm), and urinary system anatomical abnormalities were significantly associated with stone recurrence (p = 0.027, p = 0.031, p < 0.001, and p < 0.001, respectively). In adjusted logistic regression analysis, stone size ≥ 5 mm (OR 4.85, 95% CI 2.53-9.3), presence of urinary system anatomical abnormalities (OR 2.89, 95% CI 1.44-5.78), and family history of stone disease (OR 2.41, 95% CI 1.19-4.86) had increased recurrence rate. CONCLUSIONS: All children with urolithiasis should be evaluated for factors affecting stone recurrence. Children at higher risk of recurrence need to be followed carefully.

Association between urinary lithiasis, other than struvite by crystallography and non-ureolytic bacteria.

The relationship between urinary tract infection caused by urease-producing bacteria and lithiasis due to struvite stones is well established in the literature. However, there is limited knowledge on whether non-urease producing bacteria can also promote crystallization. In our study, we analyzed the association between urinary lithiasis, other than struvite by crystallography and non-ureolytic bacteria, in 153 patients who underwent surgery for urinary stone. The collected samples were sent for crystallographic analysis and culture. Additionally, preoperatory urine culture was collected for combined evaluation with the previous data. Percutaneous nephrolithotomy was the most commonly performed approach (45.8%). Struvite stones were more frequently identified in women (90.3%). Among stones with positive cultures, except struvite, 45.5% were composed of calcium oxalate monohydrate. The difference between urine culture and stone culture was different in 24.8% of the cases. Among stones with positive cultures that did not contain struvite, 86.4% showed non-urease bacteria in their cultures and 47.1% of struvite stones also did not have urease-producing bacteria in their cultures (p < 0.021). Our findings suggest that there is an association between non-ureolytic bacteria and stones that are not composed of struvite.

Litíase urinária e sua relação com os achados de cristalúria e hematúria na urinálise / Urolithiasis and its relation to the urinalysis findings of crystalluria and hematuria

Introdução: Litíase urinária é a formação de cálculos no trato urinário a partir de componentes presentes na urina. É uma doença crônica associada a um alto número de recorrência e hospitalizações. O objetivo do estudo foi verificar a frequência de cristalúria e a relação entre litíase urinária e os achados de cristalúria e hematúria em pacientes da região noroeste do estado do Rio Grande do Sul. Métodos: Estudo transversal no qual foram incluídos pacientes no período de março a dezembro de 2015. Exames qualitativos de urina e prontuários médicos foram revisados buscando-se dados de cristalúria e hematúria e diagnóstico da litíase. Resultados: Foram analisadas 688 amostras de urina, e 54 (7,85%) apresentaram cristalúria. Dos casos de cristalúria, cinco (9,3%) pacientes apresentaram litíase. Foi verificada significância estatística (p = 0,010) entre as variáveis de litíase e hemácias, mas não foi evidenciada significância estatística entre as variáveis de litíase e cristalúria (AU)

Introduction: Urolithiasis is the formation of stones in the urinary tract from urine components. It is a chronic disease associated high recurrence and hospitalization rates. The aim of this study was to determine the frequency of crystalluria and the relation between urolithiasis and crystalluria and hematuria findings in patients of northwestern Rio Grande do Sul. Methods: A cross-sectional study that enrolled patients from March to December of 2015. Urinalyses and medical records were reviewed searching for crystalluria and hematuria data, and diagnosis of lithiasis. Results: 688 urine samples were analyzed, and crystalluria was found in 54 (7.85%) of them. Considering the crystalluria cases, 5 (9.3%) of the patients also had lithiasis. Statistical significance was found (p = 0.010) between the variables of lithiasis and red blood cells, but no statistical significance was found between the variables of lithiasis and crystalluria. Conclusion: Crystalluria was not associated with lithiasis, while hematuria was associated with such disease (AU)

Metabolic assessment of elderly men with urolithiasis

OBJECTIVE: To assess the presence of metabolic disorders in elderly men with urolithiasis. METHODS: We performed a case-control study. The inclusion criteria were as follows: (1) men older than 60 years of age and either (2) antecedent renal colic or an incidental diagnosis of urinary lithiasis after age 60 (case arm) or (3) no antecedent renal colic or incidental diagnosis of urolithiasis (control arm). Each individual underwent an interview, and those who were selected underwent all clinical protocol examinations: serum levels of total and ionized calcium, uric acid, phosphorus, glucose, urea, creatinine and parathyroid hormone, urine culture, and analysis of 24-hour urine samples (levels of calcium, citrate, creatinine, uric acid and sodium, pH and urine volume). Each case arm patient underwent two complete metabolic urinary investigations, whereas each control arm individual underwent one examination. ClinicalTrials.gov: NCT01246531. RESULTS: A total of 51 subjects completed the clinical investigation: 25 in the case arm and 26 in the control arm. In total, 56% of the case arm patients had hypocitraturia (vs. 15.4% in the control arm; p = 0.002). Hypernatriuria was detected in 64% of the case arm patients and in 30.8% of the controls (p = 0.017). CONCLUSION: Hypocitraturia and hypernatriuria are the main metabolic disorders in elderly men with urolithiasis.

Study of urinary acidification in patients with idiopathic hypocitraturia

Hypocitraturia (HCit) is one of the most remarkable features of renal tubular acidosis, but an acidification defect is not seen in the majority of hypocitraturic patients, whose disease is denoted idiopathic hypocitraturia. In order to assess the integrity of urinary acidification mechanisms in hypocitraturic idiopathic calcium stone formers, we studied two groups of patients, hypocitraturic (HCit, N = 21, 39.5 + or - 11.5 years, 11 females and 10 males) and normocitraturic (NCit, N = 23, 40.2 + or - 11.7 years, 16 females and 7 males) subjects, during a short ammonium chloride loading test lasting 8 h. During the baseline period HCit patients showed significantly higher levels of titratable acid (TA). After the administration of ammonium chloride, mean urinary pH (3rd to 8th hour) and TA and ammonium excretion did not differ significantly between groups. Conversely, during the first hour mean urinary pH was lower and TA and ammonium excretion was higher in HCit. The enhanced TA excretion by HCit during the baseline period and during the first hour suggests that the phosphate buffer mechanism is activated. The earlier response in ammonium excretion by HCit further supports other evidence that acidification mechanisms react promptly. The present results suggest that in the course of lithiasic disease, hypocitraturia coexists with subtle changes in the excretion of hydrogen ions in basal situations

Hipercalciuria idiopática en pediatria: experiencia de 5 años / Idiopathic hypercalciuria in pediatrics: experience of 5 years

El estudió de la hipercalciuria idiopática en pediatría requiere contar con información local. Se presentan los resultados de la medición de excresión urinaria de calcio en 97 niños sanos, medido a través del índice calciuria creatininuria, resultando un promedio de 0,13 y una mediana de 0,08. Se evalúa igualmente la relación entre calciuria así determinada y la excresión urinaria de sodio (n:47), demostrándose una correlación estadísticamente significativa, r de 0,41, p<0,01. La validez del índice calcio/creatinina en orina aislada frente al calcio en orina de 24 horas (n:44) se confirmó al obtener una alta correlación (r:0,89, p<0.001) entre ambos. Al comparar la eficacia de la prueba de restricción y sobrecarga de calcio con la restricción simple de calcio en el diagnóstico diferencial de las hipercalciurias idiopáticas (n:78) absortiva y renal, se observó que la exactitud del ensayo de restricción simple es mayor

Hipercalciuria idiopática en pediatría / Idiopathic hypercalciuria in pediatrics

Hace 50 años se observó que pacientes portadores de litiasis renal presentaban una excreción aumentada de calcio en orina. Posteriormente Albrigth y Henneman describieron un grupo de pacientes adultos con litiasis renal que presentaban hipercalciuria en ausencia de hipercalcemia, hiperfosfemia, alteraciones óseas, ingesta de vitamina D, ingesta de calcio, tumores, acidosis renal tubular, endocrinopatías o situaiones de rápida reabsorción ósea como inmovilización o enfermedad de Paget. En ese momento fue acuñado el término de hipercalciuria idiopática (HI) para describir este grupo de enfermos

Anotaciones sobre litiasis renal / Annotations about nephrolithiasis

La lititasis renal es un trastorno relativamente frecuente en la practica medica. No existe en la literatura colombiana una revision reciente y actualizada acerca de este tema por lo cual se escribio la presente. En una forma practica y simplificada, pero completa, se analizan los diferentes aspectos relacionados con la litiasis por calcio y brevemente, se mencionan otros tipos de calculos. Se hace enfasis en fisiopatologia, evaluacion del paciente, manejo de la litiasis (liquidos, dieta y drogas) y nuevos metodos de extraccion de calculo. No se incluye el manejo del colico renal

Nephrolithiasis is a relatively common disease in medical practice. There are no recent, updated reviews on this topic in Colombian literature and to fill this need the present one was written. The different aspects of calcium lithiasis are analyzed in a practical and simplified although comprehensive way, emphasizing pathophysiology, patient evaluation, management of lithiasis (fluids, diet and drug therapy) and new methods for stone removal. Other types of calculi are briefly discussed. Management of the renal colic is not included