Treatment of BK virus with a stepwise immunosuppression reduction and intravenous immunoglobulin in pediatric kidney transplant.

BACKGROUND: BKV and BKVN are common in pediatric kidney transplant, but there is limited data on treatment approaches. Our objective was to study the prevalence of BKV and BKVN utilizing only plasma qPCR and report treatment outcomes with stepwise IR and IVIG. METHODS: A retrospective study of all pediatric kidney transplants from 2013 to 2020. Excluded patients >21 years at transplant and immediate graft failure. Surveillance was conducted using only plasma BK qPCR at 1, 3, 6, 9, 12, 18, and 24 months and annually. BKV defined as ≥250 copies/ml and resolution as <250 copies/ml. Presumed BKVN as >10 000 copies/ml despite IR; and BKVN if confirmed on histology. RESULTS: Fifty-six patients were included in the study; 20 (35.7%) had BKV. BKV was associated with longer duration of stent, 40 vs. 33.5 days (p = .004). Two patients (3.5%) had confirmed, and 2(3.5%) had presumed BKVN. The first-line treatment was IR in 100% of patients. BKVN confirmed and presumed received IVIG every month for six doses. Viral resolution was achieved in 70%, and no difference was noted in estimated glomerular filtration rate between BKV and non-BKV group (p = .438). There were no rejection episodes, and graft survival was 100% over median follow-up of 3 years. CONCLUSIONS: Plasma qPCR alone is adequate for screening and monitoring treatment of BKV and BKVN. A stepwise IR and IVIG resulted in BKV resolution in the majority of patients. Larger studies are required to study the role of IVIG in the treatment of BKVN.

Kidney Echogenicity and Vesicoureteral Reflux in Children with Febrile Urinary Tract Infection.

OBJECTIVE: To evaluate increased kidney echogenicity as a predictor of vesicoureteral reflux (VUR) in young children with first febrile urinary tract infection (UTI). STUDY DESIGN: We performed a single center retrospective study of hospitalized children with first febrile UTI diagnosed in accordance with the American Academy of Pediatrics guidelines. All patients had kidney bladder ultrasound (KBUS) and voiding cystourethrography. Variables analyzed using χ2 test or Mann-Whitney U test as appropriate. Multivariable logistic regression analysis was performed for the abnormal KBUS findings and OR and 95% CI were calculated. RESULTS: Our cohort included 415 children (830 kidney units) with median age of 5 months (1 month to 5 years) and 80% were female. One hundred thirty-two (31.8%) patients had abnormal KBUS, including increased echogenicity in 45 patients. Overall, 42.2% of patients with increased echogenicity had VUR vs 23.3% with normal ultrasound (P = .013) and 31.1% of patients with increased echogenicity had high-grade III-V VUR vs 8.1% with normal ultrasound (P = .001). In total, 24.3% of kidneys with increased echogenicity had VUR vs 20% with normal ultrasound (P = .246) and 20% of kidneys with increased echogenicity had high-grade III-V VUR vs 9.9%with normal ultrasound (P = .005). CONCLUSIONS: These data support adding increased kidney echogenicity to the list of other KBUS findings that are helpful in decision making about a need for voiding cystourethrography in young children with first febrile UTI.

Primary Vesicoureteral Reflux and Renal Scarring.

Vesicoureteral reflux (VUR) is the commonest congenital anomaly of urinary tract in children. It is mostly diagnosed after a urinary tract infection or during evaluation for congenital anomalies of the kidney and urinary tract. High-grade VUR, recurrent pyelonephritis, and delayed initiation of antibiotic treatment are important risk factors for renal scarring. The management of VUR depends on multiple factors and may include surveillance only or antimicrobial prophylaxis; very few patients with VUR need surgical correction. Patients with renal scarring should be monitored for hypertension and those with significant scarring should also be monitored for proteinuria and chronic kidney disease.

Acute Kidney Injury in Pediatric Acute SARS-CoV-2 Infection and Multisystem Inflammatory Syndrome in Children (MIS-C): Is There a Difference?

Objective: To evaluate the prevalence and factors associated with the risk of acute kidney injury (AKI) in pediatric patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and multisystem inflammatory syndrome in children (MIS-C). Study Design: We performed a retrospective chart review of 113 patients with SARS-CoV-2 infection with or without MIS-C admitted at Children's Hospital of Michigan (CHM) from March to August 2020. Patient demographic details, laboratory data, imaging studies, echocardiography reports, and treatment data were collected. Results: Of the 92 patients included in the final analysis, 22 (24%) developed AKI with 8/22 (36%) developing stage 3 AKI. The prevalence of AKI was much higher in patients with MIS-C 15/28 (54%) vs. those with acute SARS-CoV-2 infection 7/64 (11%), (p < 0.001). Overall, when compared to patients without AKI, patients with AKI were older in age (11 vs. 6.5 years, p = 0.007), African American (86 vs. 58%, p = 0.028), had MIS-C diagnosis (68 vs. 19%, p < 0.001), required ICU admission (91 vs. 20%, p < 0.001), had cardiac dysfunction (63 vs. 16%, p < 0.001), required inotropic support (59 vs. 6%, p < 0.001) and had a greater elevation in inflammatory markers. In a multivariate analysis, requirement of inotropes [Odds Ratio (OR)-22.8, p < 0.001], African American race (OR-8.8, p = 0.023) and MIS-C diagnosis (OR-5.3, p = 0.013) were the most significant predictors for AKI. All patients had recovery of kidney function, and none required kidney replacement therapy. Conclusion: Children with acute SARS-CoV-2 infection and MIS-C are at risk for AKI, with the risk being significantly greater with MIS-C. The pathogenesis of AKI in acute SARS-CoV-2 infection appears to be a combination of both renal hypo-perfusion and direct renal parenchymal damage whereas in MIS-C, the renal injury appears to be predominantly pre-renal from cardiac dysfunction and capillary leak from a hyperinflammatory state. These factors should be considered by clinicians caring for these children with a special focus on renal protective strategies to aid in recovery and prevent additional injury to this high-risk subgroup.

Postinfectious Glomerulonephritis.

Postinfectious glomerulonephritis continues to be the most common cause of acute glomerulonephritis in children. Although in the past it was considered to be mainly a complication of streptococcal infections, today it is well known that infection with many other pathogens may trigger an immune response that results in glomerular injury. Most children with postinfectious glomerulonephritis have an excellent prognosis with complete recovery of renal function and no recurrence. This article summarizes the history, presentation, evaluation, differential diagnosis, and management of children with postinfectious glomerulonephritis. [Pediatr Ann. 2020;49(6):e273-e277.].