RESUMO
BACKGROUND: Historically, due to the lack of distinct clinical symptoms, Alport syndrome, a hereditary kidney disease prevalent in children and a leading cause of kidney failure, has often been misdiagnosed as other kidney conditions. CASE DESCRIPTION: This article presents a comprehensive review and analysis of clinical data concerning a child diagnosed with Alport syndrome, where nephrotic syndrome served as the primary manifestation. The male child in this case exhibited symptoms starting at the age of 6, initially diagnosed as nephrotic syndrome. Consequently, oral steroid medication was administered, proving ineffective. Due to persistent proteinuria and microscopic hematuria, a renal biopsy was performed. Immunofluorescence staining revealed no abnormal expression of the α3, α4, and α5 chains of type IV collagen. Notably, electron microscopy revealed the basement membrane to be partially torn and arachnoid. Genetic testing indicated a hemizygous COL4A5 acceptor-splice-site mutation c.4707-1(IVS50)G > A, inherited from his mother. CONCLUSION: This specific mutated locus, being the first of its kind reported, adds valuable information to the existing gene mutation spectrum of Alport syndrome. Consequently, it emphasizes the importance for clinicians to deepen their understanding of rare kidney diseases, contributing to enhanced diagnostic accuracy and improved patient care.