Patients with chronic kidney disease (CKD) bear a significant financial burden and face numerous complications and higher mortality rates. The progression of CKD is associated with glomerular injury caused by glomerular hyperfiltration and oxidative stress. Factors such as uncontrolled hypertension, elevated urine protein levels, anemia, and underlying glomerular disease, contribute to CKD progression. In addition to conservative treatment, several medications are available to combat the progression of CKD to end-stage kidney disease. Renin-angiotensin-aldosterone system blockers could slow the progression of CKD by reducing glomerular hyperfiltration, lowering blood pressure, and decreasing inflammation. Mineralocorticoid receptor antagonists inhibit the mineralocorticoid receptor signaling pathway, thereby attenuating inflammation and fibrosis. Sodium-glucose cotransporter 2 inhibitors exhibit protective effects on the kidneys and against cardiovascular events. Tolvaptan, a selective vasopressin V2-receptor antagonist, decelerates the rate of increase in total kidney volume and deterioration of kidney function in patients with rapidly progressive autosomal dominant polycystic kidney disease. The protective effects of AST-120 remain controversial. Due to a lack of evidence regarding the efficacy and safety of these medications in children, it is imperative to weigh the benefits and adverse effects carefully. Further research is essential to establish the efficacy and safety profiles in pediatric populations.

Purpose: Hematuria and proteinuria have various causes and consequential outcomes in children. Immunosuppressants are needed in some children with biopsy-proven glomerulonephropathy but have many adverse effects. Since the clinical practice patterns of Korean pediatric nephrologists are diverse, we surveyed their opinions. Methods: Using a clinical vignette, the survey was emailed to all Korean Society of Pediatric Nephrology members. The questionnaires included diagnosis, examination, medications, and dietary recommendations for patients with hematuria and proteinuria. Results: A total of 32 clinicians (5.48%, 22 pediatric certificated nephrologists) responded to the survey. Most responders (87.5%) suspected immunoglobulin A nephropathy, and 68.8% replied that kidney biopsies were a diagnostic tool. Renin-angiotensin system inhibition (62.5%) or steroids (18.8%) were selected as the treatment. Salt and protein intakes were usually encouraged as dietary reference intakes (34.4% and 65.6%, respectively). Conclusions Children with abnormal urinalysis have various causes, treatments, and prognoses. As treatments such as immunosuppressants can have many adverse effects, it is necessary to confirm an accurate diagnosis and indications of treatments before starting the treatment. Recommendations for a diet should not hinder growth.

Renal tubular dysgenesis (RTD) is a rare fatal disorder in which there is poor development of proximal tubules, leading to oligohydramnios and the Potter sequences. RTD occurs secondary to renin-angiotensin system (RAS) blockade during the early stages of fetal development or due to autosomal recessive mutation of genes in the RAS pathway. A boy born at 33+1 weeks due to cord prolapse was found to be anuric and hypotensive. Pregnancy was complicated by severe oligohydramnios from gestational age 28+4 weeks. Abdominal sonography revealed diffuse globular enlargement of both kidneys with increased cortical parenchymal echogenicity. Infantogram showed a narrow thoracic cage and skull X-ray showed large fontanelles and wide sutures suggestive of ossification delay. Basal plasma renin activity was markedly elevated and angiotensin-converting enzyme was undetectable. Despite adequate use of medications, peritoneal dialysis, and respiratory support, he did not recover and expired on the 23rd day of life. At first, autosomal recessive polycystic kidney disease was suspected, but severe oligohydramnios along with refractory hypotension, anuria, skull ossification delay and high renin levels made RTD suspicious. ACE gene analysis revealed compound heterozygous pathogenic variations of c.1454.dupC in exon 9 and c.2141dupA in exon 14, confirming RTD. Based on our findings, we propose that, although rare, RTD should be suspected in patients with severe oligohydramnios and refractory hypotension.

C1q nephropathy is a rare glomerulopathy that typically presents with nephrotic syndrome in children. Treatment with immunosuppressive agents renders patients vulnerable to infection and its complications. Gastroenteritis is common in children, and rotavirus is a leading cause. Extraintestinal manifestations of rotavirus have recently been reported; however, there is a paucity of cases exploring the involvement of a rotavirus on the respiratory system. Acute respiratory distress syndrome (ARDS) is a rapid onset respiratory failure characterized by noncardiogenic pulmonary edema and hypoxemia. Causes of ARDS include sepsis, pneumonia, pancreatitis, aspiration, and trauma. In this paper, we report a case of ARDS after rotavirus infection in a child with C1q nephropathy who had been treated with immunosuppressive agents.

Chronic kidney disease (CKD)-mineral and bone disorder (CKD-MBD) is a common complication of CKD, often accompanied by extra-skeletal calcification in adult patients. As increased vascular calcification is predicted to increase cardiovascular mortality and morbidity, the revised Kidney Disease: Improving Global Outcomes guidelines recommend avoiding calcium-containing phosphate chelators. However, extra-skeletal calcification is less commonly noticed in pediatric patients. Here, we report our experience of such a complication in pediatric patients receiving maintenance peritoneal dialysis. Extra-skeletal calcification was noticed at the corneas, pelvic cavity, and soft tissues of the lower leg in 4 out of 32 patients on maintenance peritoneal dialysis. These patients experienced the aggravation of extra-skeletal calcifications during peritoneal dialysis, and 2 of them underwent excisional operations. It is required to monitor extra-skeletal calcifications in children on kidney replacement therapy.