Nephrolithiasis and/or nephrocalcinosis is significantly related to renal dysfunction in patients with primary Sjögren's syndrome.

OBJECTIVE: The present study compared the clinical features of patients with primary Sjögren's syndrome (pSS) with and without nephrolithiasis and/or nephrocalcinosis to determine factors related to renal dysfunction. METHODS: The clinical features of 68 patients with anti-Sjogren's syndrome antigen A (SSA)/Ro-antibody-positive pSS with and without nephrolithiasis and/or nephrocalcinosis who underwent abdominal computed tomography and/or ultrasonography were retrospectively analysed. RESULTS: Of the 68 patients with anti-SSA-antibody-positive pSS, 23 (33%) had renal nephrolithiasis and/or nephrocalcinosis, whereas 45 (67%) did not. Fourteen (20%) patients had renal dysfunction at diagnostic imaging. Among five patients who underwent renal biopsy, four patients with renal nephrolithiasis and/or nephrocalcinosis were diagnosed with tubulointerstitial nephritis, and one without nephrolithiasis and/or nephrocalcinosis was diagnosed with minimal change nephrotic syndrome. Estimated glomerular filtration rate at diagnostic imaging was significantly lower in patients with than without nephrolithiasis and/or nephrocalcinosis group (P = 0.010). In addition to nephrolithiasis and/or nephrocalcinosis (odds ratio [OR], 3.467; P = 0.045), the gap between serum sodium and chloride concentrations (OR, 10.400; P = 0.012) and increased urinary ß2-microglobulin (OR, 5.444; P = 0.033) were associated with renal dysfunction at the time of diagnostic imaging. CONCLUSION: Nephrolithiasis and/or nephrocalcinosis, normal anion gap metabolic acidosis, and tubulointerstitial damage are associated with renal dysfunction in patients with pSS.

Use of Low-Dose Computed Tomography in Children With Nephrolithiasis: An Analysis From 2 Tertiary Pediatric Centers.

INTRODUCTION: Although ultrasound (US) is the preferred first-line imaging for pediatric nephrolithiasis, CT may be necessary in cases of a nondiagnostic US or when US in not available. Utilization of dose reduction strategies in children undergoing CT for nephrolithiasis is not well described. We compared use of low-dose CT (LDCT) in children presenting to 2 pediatric centers. METHODS: We performed a retrospective chart review of children ≤ 17 years of age presenting with suspected nephrolithiasis to 2 tertiary children's hospitals, inclusive of those referred to these centers from nonpediatric facilities between 2013 and 2019. Children were included with an index CT scan from either the pediatric or referring center while those who had prior documented CT for nephrolithiasis within the study period or missing radiation dose assessment were excluded. The primary outcome was LDCT as defined as radiation dose < 3 mGy. The primary comparator was pediatric vs outside referral center. Exploratory analysis evaluated other factors associated with LDCT, including radiation dosage as a continuous variable. RESULTS: A total of 155 individuals met inclusion criteria, with 126 (81.3%) receiving standard dose and 29 (18.7%) receiving LDCT. Pediatric facilities were more likely to utilize LDCT as compared to referral centers (P < .05). Older age and higher BMI were also found to be associated with increased radiation dose exposure. CONCLUSIONS: Pediatric facilities utilized LDCT more frequently, although age and BMI may also influence imaging choices. An understanding of the factors associated with dose reduction in CT will impact future efforts to explore optimum imaging stewardship in pediatric nephrolithiasis.

Children With Type 1 Spinal Muscular Atrophy Are at Increased Risk for Nephrolithiasis.

BACKGROUND: Nephrolithiasis is not a well-documented condition in children with spinal muscular atrophy (SMA). It is possible that this condition was underestimated before the era of nusinersen because of a much shorter life expectancy. We present our observational data on nephrolithiasis and its possible risk factors in children with type 1 SMA. METHODS: We retrospectively reviewed the charts of 20 children with genetically confirmed type 1 SMA. Thirteen patients (aged 9 to 55 months) who underwent urinary tract ultrasonography were included in the study. Medical records were retrospectively reviewed for demographic and clinical characteristics, ultrasound results, and metabolic abnormalities. RESULTS: Seven children (54%) had nephrolithiasis; 5 had multiple stones and two had a single stone. Two patients had microlithiasis (<3 mm), three had a stone in the size of 3 to 5 mm, and one had a stone in the size of more than 8 mm. Two patients with nephrolithiasis had urinary tract abnormalities. Patients with nephrolithiasis were more likely to have a history of urinary tract infections (UTIs) (P = 0.048) and higher urine specific gravity (P = 0.014) than patients without nephrolithiasis. Five of seven children with nephrolithiasis had a urine metabolic evaluation; all had hypercalciuria, three had hyperuricosuria, but none had hyperoxaluria, hypocitraturia, or hypomagnesemia. CONCLUSION: Children with SMA type 1 are at an increased risk for nephrolithiasis. Hypercalciuria and high urine specific gravity appear to be the most common risk factors for the occurrence of nephrolithiasis. In addition, UTI is more common in patients with type 1 SMA with nephrolithiasis.

High perirenal fat thickness predicts a greater risk of recurrence in Chinese patients with unilateral nephrolithiasis.

INTRODUCTION: The aim of this study was to evaluate the association between recurrence-free survival (RFS) and perirenal fat thickness (PFT) in a cohort of Chinese population with unilateral nephrolithiasis. METHODS: We retrospectively reviewed the medical records of 81 patients with unilateral nephrolithiasis in our center from January 2019 to June 2019. PFT measured on computed tomography (CT) scans was evaluated. Kaplan-Meier curves and log-rank tests were used to assess significant differences in RSF between high-PFT and low-PFT groups within sexes. Univariable and multivariable Cox regression analyses were used to evaluate the potential risk factors for renal stone recurrence. RESULTS: High PFT was significantly associated with high BMI and hyperlipidemia (p = .003 and.047, respectively). The PFT of stone-bearing kidney was significantly greater than PFT of non-stone-bearing kidney (0.77 ± 0.60 cm vs. 0.67 ± 0.58 cm, p = .002) . During the follow-up periods (median 31 months), 21 (25.9%) patients experienced ipsilateral renal stone recurrence. In addition, Kaplan-Meier survival curves showed that patients with low PFT had a significant better RFS than those with high PFT (p = .012). In the univariable Cox analyses, male sex and high PFT were significantly associated with a poor RFS (p = .042 and .018, respectively). Moreover, both male sex and high PFT retained significance in the multivariable analyses (p = .045 and .020, respectively). CONCLUSIONS: Our findings suggested that PFT is a noninvasive and feasible parameter, which may help in the risk stratification of renal stone recurrence in the follow-up periods.

Progression of asymptomatic nephrolithiasis in children: How often should patients receive follow-up ultrasound imaging?

INTRODUCTION: The natural history of asymptomatic nephrolithiasis (AN) in children is not well defined. Furthermore, there is no guidance on the utility of repeated renal ultrasound evaluations in this same population. Follow-up ultrasound studies are often obtained as frequently as every 6 months. The goal of this study is to assess the follow-up ultrasound interval in the management of these patients. METHODS: A retrospective IRB approved chart review was performed for patients seen for non-cysteine AN between 2012 and 2019. AN was defined as patients without obstructive uropathy abdominal, flank pain and/or gross hematuria. Asymptomatic stones were discovered incidentally or after an acute stone event. Patients with pre-existing renal anomalies and the timepoints with stone passage or stone procedure were excluded. Descriptive statistics were used for demographic information. Multiple linear regression was used to analyze risk factors. Statistical significance was set to p < 0.05. RESULTS: Twenty-nine patients had 90 ultrasounds. The average age at diagnosis was 10.8 ± 6.2 years. The average number of ultrasound studies per patient was 3.2 ± 1.7. The median time between follow-up ultrasounds was 5.2 months [IQR 2.8-10.0]. Median follow-up of patients was 10.6 months [IQR 4.9-21.9]. The change in total stone burden occurred at a rate of 0.11 mm/month (CI [-0.06-0.28], p = 0.20, r2 = 0.42) or 0.66 mm/6 months. Patients with more renal stones had almost a threefold increase in stone burden compared to patients with fewer renal stones (2.98 [CI 1.34-4.62], p=0.001, r2=0.33). Patients with a family history of stones had a twofold increase in the size of their largest stone when compared to patients without a family history (1.97 [CI 0.26-3.68], p=0.02, r2=0.60. CONCLUSION: A complex interplay of multiple factors influence the progression of AN in children. Children with a greater number of stones have a higher increase in total stone burden and children with a family history of stones have a faster increase in largest stone size. These patients may require more frequent imaging studies. The small change in stone size over time favors a longer than 6-month interval for many children.

Is Retrograde Intrarenal Surgery as Safe for Children as It Is for Adults?

INTRODUCTION: The primary aim of this study is to compare the efficacy and safety of retrograde intrarenal surgery (RIRS) among the children and adults with similar stone burdens and locations. Also, the secondary aim of this study is to identify the factors affecting the stone-free rates (SFRs) of RIRS. METHODS: We retrospectively compared perioperative results, SFRs, and complication rates (CRs) between pediatric (group 1, n: 55) and adult (group 2, n: 220) age groups diagnosed with kidney stones and treated by flexible ureterorenoscopy using the same instruments. Furthermore, multivariate analysis was performed to determine the factors affecting the SFR. RESULTS: A total of 275 patients (pediatric group: 55; adult group: 220) were included in this study. The mean age of pediatric and adult groups was 7.2 ± 5.3 and 43.9 ± 15.1, respectively. The mean stone size was 13.9 ± 6.6 mm in the pediatric group compared to 14.8 ± 6.7 mm in the adult group (p = 0.35). Stone localizations and number were similar. JJ stenting for passive dilatation and use of UAS were higher in the pediatric group (p = 0.002; p = 0.017). However, postoperative double pigtail stenting rate was higher in the adult group (p < 0.001). Total CR was 13.8% and mostly Clavien I-II, and no difference was observed between the 2 groups (p = 0.541). The SFRs between the groups were similar (pediatric group: 81.8%; adult group: 78.2%; p = 0.554). On multivariate analysis, stone size (p < 0.001) and lower calyx stone (p < 0.001) were the negative predictive factors for SFR. CONCLUSION: There are small technical differences between pediatric patients and adult patients in our study, but RIRS in children is as safe and efficient as it is in adults.

Efficacy of a fast-track pathway for managing uncomplicated renal or ureteral colic in a hospital emergency department: the STONE randomized clinical trial of Sonography and Testing of a Nephrolithiasis Episode. / Eficacia de una vía de alta resolución en la evaluación del cólico renoureteral no complicado en un servicio de urgencias hospitalario: un ensayo clínico aleatorizado (Estudio STONE).

OBJECTIVES: To evaluate a fast-track pathway utilizing point-of-care (POC) testing and sonography as soon as uncomplicated renal or ureteral colic is suspected and to compare the POC clinical pathway to a standard one. MATERIAL AND METHODS: Unblinded randomized controlled clinical trial in a hospital emergency department (ED). We enrolled patients with suspected uncomplicated renal or ureteral colic and randomized them to a POC or standard pathway (1:1 ratio). Duration of ED stay, treatments, the proportion of diagnoses other than uncomplicated colic, and 30-day complications were analyzed. RESULTS: One hundred forty patients were recruited between November 2018 and October 2019; data for 124 were analyzed. The mean (SD) total time in the ED was 112 (45) minutes in the POC arm and 244 (102) in the standard arm (P .001). Treatments, alternative diagnoses, and complication rates did not differ. CONCLUSION: The use of a fast-track POC pathway to manage uncomplicated colic in the ED is effective and safe. It also reduces the amount of time spent in the ED.

OBJETIVO: Evaluar una vía de alta resolución (vía POC) que utiliza análisis en el punto de atención (point-of-care testing ­POCT­) y ecografía en el punto de atención (point-of-care ultrasonography ­POCUS­) en la sospecha del cólico renoureteral (CRU) no complicado y compararla con la vía estándar (vía STD). METODO: Ensayo clínico aleatorizado, controlado, no ciego, realizado en un servicio de urgencias hospitalario (SUH). Incluyó pacientes con sospecha clínica de CRU agudo y se aleatorizaron 1:1 a seguir vía POC o vía STD. Se analizó el tiempo de estancia en el SUH, el tratamiento administrado, la proporción de diagnósticos alternativos a CRU y las complicaciones a 30 días. RESULTADOS: Entre noviembre de 2018 y octubre de 2019, se reclutaron 140 pacientes de los que se analizaron 124. El tiempo de estancia total en el SUH de la vía POC fue de 112 minutos (DE 45) y en la vía STD 244 minutos (DE 102) (p 0,001). No hubo diferencias en el tratamiento administrado en urgencias, en el número de diagnósticos alternativos, ni en las complicaciones a 30 días. CONCLUSIONES: La utilización de una vía de alta resolución del manejo del CRU en un SUH es eficaz, segura y reduce el tiempo de estancia en urgencias.

Pielonefritis enfisematosa / Emphysematous pyelonephritis

La pielonefritis enfisematosa es una enfermedad poco frecuente. Esta consiste en una infección necrotizante severa del parénquima renal asociada a formación de gas en el sistema colector, parénquima renal y/o tejidos perirrenales. Se presenta una paciente de 54 años de edad con antecedentes de diabetes mellitus tipo 2 no controlada y litiasis urinaria, atendida en el Cuerpo de Guardia del Hospital Celia Sánchez Manduley, Granma, Cuba. Presentaba náuseas y vómitos, dolor en ambos lados de la región lumbar, y fiebre. La ecografía mostró riñones hiperecogénicos e imágenes ecorefringentes en proyección de las cavidades renales. El cultivo de orina probó la presencia de escherichia coli, y se medicó de forma endovenosa. Por evolución no favorable, se realizó tomografía que evidenció patrón gaseoso en cavidades renales. Se reajustó la antibioticoterapia parenteral y la evolución fue favorable. Se dio alta de consulta, luego de 10 meses de seguimiento asintomática, con diagnóstico de pielonefritis enfisematosa(AU)

Emphysematous pyelonephritis is a rare disease, consisting of severe necrotizing infection of the renal parenchyma associated with gas formation in the collecting system, renal parenchyma and / or peri renal tissues. We report a 54-year-old patient with history of uncontrolled type 2 diabetes mellitus and urinary stones, she was treated in the emergency service at Celia Sánchez Manduley Hospital, Granma, Cuba. She had nausea and vomiting, pain on both sides of her lower back, and fever. Ultrasound showed hyper-echogenic kidneys and echo-refractive images in projection of the renal cavities. The urine culture proved the presence of Escherichia coli, and medications was administered intravenously. Due to the unfavorable evolution, a tomography was performed and it showed a gas pattern in the renal cavities. Parenteral antibiotic therapy was readjusted and the outcome was favorable. After 10 months of asymptomatic follow-up, she was discharged from the clinic with diagnosis of emphysematous pyelonephritis(AU)

SONO case series: 35-year-old male patient with flank pain.

The diagnosis and management of obstructing nephrolithiasis by emergency physicians has undergone great advancements in the past few years. No longer do all patients with suspected renal colic need a CT scan and an immediate urology consult. In this case presentation, we present a classic case of obstructing nephrolithiasis along with the associated point-of-care ultrasound images. We will walk with the reader through a series of questions and answers discussing the patient's diagnosis based on the most current evidence-based recommendations.

Ultrasonography for diagnosis and management of nephrolithiasis: state of the art and new perspectives / L'ultrasonografia nella diagnosi e nel management della nefrolitiasi: stato dell'arte e prospettive future

The correct management of patients with kidney stones is a crucial issue for nephrologists. In recent years, the incidence and prevalence rates of nephrolithiasis have maintained a growing trend worldwide, showing a strong correlation with other systemic disease such as diabetes mellitus, hypertension, obesity, metabolic syndrome and chronic kidney disease. International guidelines indicate computed tomography as the first choice for all adult patients with suspected acute symptoms for obstructive nephrolithiasis. Intravenous pyelogram is more useful in the follow-up of patients with relapsing nephrolithiasis and known stone composition, while the high costs and the long image acquisition times limit the routine use of magnetic resonance. Recent innovative tools have improved the accuracy of kidney stone localization and measuring with B-Mode and color Doppler imaging, thereby reducing the gap between ultrasonography and computer tomography. The aim of this review is to report the latest evidence on risk factors and on the pathophysiology of nephrolithiasis, and to compare the utility of the available imaging techniques in the management of patients with kidney stones, focusing on the role of ultrasonography and the present and future strategies to improve its accuracy.

Association of simple renal cysts and chronic kidney disease with large abdominal aortic aneurysm.

BACKGROUND: Abdominal aortic aneurysms (AAA) primarily affect men over 65 years old who often have many other diseases, with similar risk factors and pathobiological mechanisms to AAA. The aim of this study was to assess the prevalence of simple renal cysts (SRC), chronic kidney disease (CKD), and other kidney diseases (e.g. nephrolithiasis) among patients presenting with AAA. METHODS: Two groups of patients (97 AAA and 100 controls), with and without AAA, from the Surgical Clinic Charité, Berlin, Germany, were selected for the study. The control group consisted of patients who were evaluated for a kidney donation (n = 14) and patients who were evaluated for an early detection of a melanoma recurrence (n = 86). The AAA and control groups were matched for age and sex. Medical records were analyzed and computed tomography scans were reviewed for the presence of SRC and nephrolithiasis. RESULTS: SRC (74% vs. 57%; p<0.016) and CKD (30% vs. 8%; p<0.001) were both more common among AAA than control group patients. On multivariate analysis, CKD, but not SRC, showed a strong association with AAA. CONCLUSIONS: Knowledge about pathobiological mechanisms and association between CKD and AAA could provide better diagnostic and therapeutic approaches for these patients.

Evaluation of a child with suspected nephrolithiasis.

PURPOSE OF REVIEW: As the incidence of nephrolithiasis in children doubles every 10 years it is becoming a common disease associated with significant morbidity along with considerable economic burden worldwide. The aim of this review is to summarize current data on the epidemiology and causes of renal stones in children and to provide a frame for the first clinical evaluation of a child with suspected nephrolithiasis. RECENT FINDINGS: Dietary and environmental factors are the driving force of changing epidemiology. Diagnosis should be based on medical history, presenting signs, examination, first laboratory and radiological workup. Ultrasound should be the initial diagnostic imaging performed in pediatric patients while low-dose computed tomography is rarely necessary for management. Metabolic factors including hypercalciuria, hypocitraturia, low fluid intake as well as specific genetic diseases should be explored after the resolution of initial signs and symptoms. SUMMARY: Appropriate initial evaluation, imaging technique, identification of risk factors and other abnormalities are essential for early diagnosis and prevention of stone-related morbidity in children with suspected nephrolithiasis.

Volumetric evaluation of renal sinus adipose tissue on computed tomography images in bilateral nephrolithiasis patients.

PURPOSE: To compare renal sinus fat volume (RSFV) separately within the right and left kidneys between bilateral nephrolithiasis patients and healthy controls. METHODS: This cross-sectional study analyzed patients who underwent unenhanced abdominal computed tomography (CT) divided into nephrolithiasis (n = 102) and healthy control (n = 130) groups. Age, sex, blood pressure [systolic blood pressure (SBP) and diastolic blood pressure (DBP)], estimated glomerular filtration rate (eGFR), body weight, and height of each participant were extracted. Volumetric renal sinus adipose tissue was measured separately for both kidneys on CT images. Urea, serum creatinine (Scr), uric acid (UA), total serum cholesterol (TCH), serum triglyceride (TG), and serum high- and low-density lipoprotein (HDL and LDL, respectively) cholesterol levels were obtained. RESULTS: Overall, 232 participants (mean age 47 years, 50% women) were enrolled. There were no differences in sex, DBP, urea, and LDL-cholesterol between the two groups (all p > 0.05). However, nephrolithiasis patients had higher age, BMI, SBP, and RSFV; higher Scr, UA, TCH, and TG serum levels; and lower HDL-cholesterol level and eGFR. Average left RSFV was significantly higher than right RSFV in healthy controls (4.56 ± 2.29 versus 3.34 ± 1.90 cm3, p < 0.001). A significant relationship between bilateral RSFV, age, BMI, SBP, and eGFR was noted in bilateral nephrolithiasis patients. Multivariate linear regression analysis showed age, BMI, and LDL-cholesterol to be independent predictors of left RSFV, and only BMI was an independent predictor of right RSFV. CONCLUSIONS: Our data showed renal sinus adipose tissue accumulation and the relationship among RSFV, age, BMI, and LDL-cholesterol in bilateral nephrolithiasis patients.

Hypercalciuria: its value as a predictive risk factor for nephrolithiasis in asymptomatic primary hyperparathyroidism?

CONTEXT: The latest guidelines of the 4th International Workshop on Asymptomatic Primary Hyperparathyroidism (aPHPT) reintroduced hypercalciuria (i.e. urinary calcium > 400 mg/day) as criterion for surgery. However, the value of hypercalciuria as a predictor of nephrolithiasis and the correct cut-off values still need to be confirmed. OBJECTIVE: To evaluate the prevalence of silent kidney stones in a large series of patients with aPHPT and the sensibility, specificity and predictive value of different cut-off values of hypercalciuria in identifying patients with nephrolithiasis. DESIGN: One hundred seventy-six consecutive patients with aPHPT were evaluated at our Institution by serum and urinary parameters and kidney ultrasound. RESULTS: Silent nephrolithiasis was found in 38 (21.6%) patients. In the univariate and multivariate model, hypercalciuria was a predictor of nephrolithiasis using the criterion of 400 mg/24 h [(OR 2.30, (1.11-4.82) P = 0.025], 4 mg/kg/bw [OR 2.65, (1.14-6.25) P = 0.023], gender criterion [OR 2.79, (1.15-6.79) P = 0.023] and the cut-off value derived from the ROC analysis [(> 231 mg/24 h) OR 5.02 (1.68-14.97) P = 0.004]. Despite these several predictive criteria, however, hypercalciuria had a low positive predictive value (PPV), ranging from 27.4 to 32.7%. CONCLUSIONS: Hypercalciuria is a predictor of nephrolithiasis, but its PPV is low.

Evaluation of the chemical composition of nephrolithiasis using dual-energy CT in Southern Chinese gout patients.

BACKGROUND: A study to evaluate the prevalence of uric acid (UA) nephrolithiasis with dual-energy CT (DECT) and explore the risk factors for kidney stones in primary gout patients. METHODS: Eighty-four consecutive gout patients underwent urinary tract ultrasonography or DECT to confirm the existence of kidney stones. Urine and blood samples were also taken for laboratory analysis. RESULTS: Forty-one subjects (48.8%) had nephrolithiasis diagnosed; 38 had a kidney stone. Thirty-two of the 38 patients underwent a DECT scan, and 27 patients had nephrolithiasis in DECT. Among them, 63.0% (17/27) and 14.8% (4/21) of the patients had pure UA and UA-based mixed stone, respectively, and 22.2% (6/27) had a non-UA stone. Those with nephrolithiasis suffered from more frequent acute attacks and had longer disease durations of gout. At least one urine biochemical abnormality was found in 81% of patients. Forty-four (55.0%) patients presented hypomagnesuria. Forty-three (51.8%) patients had low urine volume. Unduly acidic urine (UAU) was present in 36 patients (44.4%). Hyperuricosuria was only found in ten (12.2%) patients. In comparison to the non-lithiasic group, the lithiasic group was more likely to have a UAU. Binary logistic regression showed that female gender was a protective factor, while disease duration of gout and low urine pH were risk factors for nephrolithiasis. CONCLUSION: Our results indicated that nephrolithiasis, especially UA stones, were more common than previous reports in gout patients indicated, and that disease duration of gout, and low urine pH, were risk factors for nephrolithiasis.