Severe acute kidney injury in children owing to infective endocarditis-associated immune complex glomerulonephritis: a report of two cases.

Renal involvement in infective endocarditis (IE) may manifest with different clinical patterns, including diffuse proliferative glomerulonephritis and crescentic glomerulonephritis, which may lead to haematuria and/or proteinuria. However, severe acute kidney injury (AKI) in such cases is extremely uncommon and is reported mostly in adults. Two children with rheumatic heart disease and a peri-membranous ventricular septal defect, respectively, who developed haematuria, proteinuria and severe AKI in association with IE are reported. The first case had diffuse proliferative glomerulonephritis with 10% cellular crescents, and made a complete renal recovery with antibiotics and intravenous methylprednisolone followed by oral prednisolone. However, the second case had severe crescentic glomerulonephritis which led to residual renal injury despite intravenous methylprednisolone and cyclophosphamide in combination with antibiotics. The cases illustrate that crescentic glomerulonephritis or severe diffuse proliferative glomerulonephritis should be considered as possible complications in children presenting with haematuria, proteinuria and severe AKI. Renal biopsy along with antibiotic therapy and prompt immunosuppressive therapy should be considered for the management of this potentially life-threatening condition.