A rare cause of full-house membranous glomerulopathy in an infant: Answers

Abstract

Case report-Clinical QuizA 4-month-old girl presented macroscopic hematuria and positive COVID-19 (IgG positive and IgM negative). On admission, laboratory investigations demonstrated urea and serum creatinine values of 21 mg/dl and 0.65 mg/dl, respectively. The direct Coombs test was negative. The urinalysis showed the following: hematuria, 50 RBCs/high power feld, pyuria, hemoglobin (+++), and proteinuria (122 mg/m2/day). Her kidney ultrasonography was normal, but an abdominal ultrasonography revealed mild hepatomegaly and splenomegaly.A kidney biopsy (Fig. 1) was performed and demonstrated mild mesangial expansion of 10 glomeruli and normal basement membrane thickness. Immunofuorescence studies showed glomerular staining simultaneously positive for IgG, IgA, IgM, C3, and C1q. At the ultrastructural level, subpodocyte and mesangial electron dense deposits were observed. A difuse efacement of the podocyte foot processes was observed.Questions1. What further tests should be done to confrm the diagnosis?2. Which is the most likely anatomopathological diagnosis? What are the pathological diferential diagnoses? What about the full-house pattern?3. What could be the etiology of glomerulopathy? How should this clinical condition be treated?