Evaluation of Proteinuria and Hematuria in Ambulatory Setting.

Proteinuria and/or hematuria are common findings in ambulatory settings. Proteinuria can be glomerular and/or tubular in origin and it may be transient, orthostatic, or persistent. Persistent proteinuria may be indicative of a serious kidney pathology. Hematuria, which denotes the presence of an increased number of red blood cells in the urine, can be gross or microscopic. Hematuria can originate from the glomeruli or other sites of the urinary tract. Asymptomatic microscopic hematuria or mild proteinuria in an otherwise healthy child is less likely to be of clinical significance. However, the presence of both requires further workup and careful monitoring.

Pediatric Nephrolithiasis: Risk Factors, Evaluation, and Prevention.

Pediatric nephrolithiasis is a disease of increasing prevalence and economic burden, with data showing a rising trend among girls and adolescents. Kidney stones in children tend to have a high recurrence rate related to underlying risk factors, and the aim of evaluation should be to understand such causes so that targeted therapy can be provided to decrease recurrence and complications. Metabolic, anatomic, and genetic abnormalities as well as environmental risk factors have all been implicated in the pathogenesis of nephrolithiasis. Recent studies have focused on identifying monogenic causes of nephrolithiasis and/or nephrocalcinosis in young patients that would result in personalization of treatment as well as future diagnostic implications for family members. Treatment aims to decrease stone burden and recurrence as well as minimize complications and is guided by stone size and location as well as surgical expertise. Multidisciplinary care for these patients has been on the rise to provide a more comprehensive medical and surgical support. [Pediatr Ann. 2020;49(6):e262-e267.].

Clinical significance of IgM deposition in pediatric minimal change disease.

BACKGROUND: Idiopathic nephrotic syndrome (INS) is a common pediatric disease. Minimal change disease (MCD) is the most common histopathological subtype and usually has good prognosis. However, in less common presentations, INS may have an unusual course that makes renal biopsy a necessity to identify its etiology. Immunoglobulin M (IgM) occasionally deposits in the mesangium and can be seen under immunofluorescence (IF). The role of IgM is controversial in MCD. It is likely associated with less favorable outcomes for MCD. This study aims to investigate the clinical significance of mesangial IgM deposits on the outcome of MCD in a pediatric population. METHODS: In this retrospective cohort study, we obtained native kidney biopsy samples from 192 children who were diagnosed with MCD from 2003 to 2014. The samples were divided into groups according to the histopathological deposition of IgM in biopsies under IF. The group for which biopsies showed IgM was labeled as IgM + IF (n = 77), and the group for which biopsies were without IgM was labeled as IgM-IF (n = 115). We reviewed hypertension, hematuria, and estimated glomerular filtration rate (eGFR) at the time of presentation to our institute; response to steroid therapy (remission, dependence, frequent relapses, and resistance) and response after adjuvant immunosuppressive therapy (complete remission, partial remission, frequent relapses, and no response) when indicated; development of chronic kidney disease (CKD) and end-stage renal disease during the course of the disease (ESRD). RESULTS: Our results showed that mesangial IgM deposition in MCD showed significant statistical association with hypertension at the time of presentation (P = .05). There was statistically significant association between the presence of IgM deposition and the development of steroid dependence (P = .05) and CKD during the course of the disease (P = .05). CONCLUSIONS: Our study showed that IgM deposition in MCD showed statistical association with hypertension by the time the patient presented to our institute, development of steroid dependence, and CKD. IgM may play a role in MCD. However, we recommend a prospective study to verify the role of IgM in MCD outcomes.

Weight or body surface area dosing of steroids in nephrotic syndrome: is there an outcome difference?

Although prednisone is the treatment of choice for nephrotic syndrome (NS) in childhood, the dosing regimen varies between 60 mg/m(2)/day, as recommended in early studies, to the often prescribed 2 mg/kg/day dose, which is used in common practice. Mathematical models have demonstrated that weight-based dosing can be less than body surface area (BSA)-based dosing in smaller children. To test our hypothesis that weight-based dosing would result in altered treatment outcomes in children with NS, we analyzed a cohort of 56 children (mean age 5.4 ± 3.8 years) treated with a weight-based dosing regimen. Theoretical underdosing of corticosteroids was tested by calculating a relative underdosing percentage (RUP), which was defined as the dose difference between the theoretical BSA-based dose and the actual weight-based doses divided by the BSA-based dose × 100. We found that the mean "actual" prednisone dose in our patients was 43.6 ± 19.3 mg/day; in contrast, the mean theoretical BSA-based dose was calculated to be 48.8 ± 16.7 mg/day. Among the 56 patients, 43 (76.7%) were initial responders, of whom 58% followed a frequently relapsing (FR) course. RUP was significantly higher in FR (16.6 ± 7.9%) than in infrequent relapsers (8.7 ± 9.8%) (P = 0.03). RUP was not significantly different among initial responders and nonresponders. Based on these results, we conclude that prednisone underdosing, when dosing is prescribed according to weight, does not affect the initial response to treatment, but it does increase the likelihood of a FR course in responders.

Managing urinary tract infections.

Urinary tract infections (UTI) are common in childhood. Presence of pyuria and bacteriuria in an appropriately collected urine sample are diagnostic of UTI. The risk of UTI is increased with an underlying urological abnormality such as vesicoureteral reflux, constipation, and voiding dysfunction. Patients with acute pyelonephritis are at risk of renal scarring and subsequent complications such as hypertension, proteinuria with and without FSGS, pregnancy-related complications and even end-stage renal failure. The relevance and the sequence of the renal imaging following initial UTI, and the role of antimicrobial prophylaxis and surgical intervention are currently undergoing an intense debate. Prompt treatment of UTI and appropriate follow-up of those at increased risk of recurrence and/or renal scarring are important.