Membranous nephritis associated with acquired cytomegalovirus infection in a 19-month-old baby

Membranous nephritis (MN) is a rare form of glomerulonephritis in childhood, with an incidence of 0.8 to 6.7% based on renal biopsy specimens. Although the disease is considered to be idiopathic in the majority of cases, especially in adults, MN has been associated with various infectious agents, such as hepatitis Β virus. The natural history of MN in childhood remains unknown because of its rarity, and to the best of our knowledge, no case of MN linked to cytomegalovirus (CMV) infection in an immunocompetent child has been described to date. We report here a 19-month-old female infant who presented with a maculopapular rash, fever, and nephritic-nephrotic syndrome. Virology tests for infectious diseases revealed a recent CMV infection. The renal biopsy findings were compatible with MN, while PCR analysis of the renal tissue specimen was positive for CMV DNA. Antiviral treatment (ganciclovir) resulted in full remission of proteinuria and hematuria. Two years after the initial diagnosis, the child remains well and asymptomatic without clinical or laboratory evidence of the disease.