Renal Amyloidosis in a Child with Recessive Dystrophic Epidermolysis Bullosa Due to a Novel Variant in COL7A1 Gene.

Secondary amyloidosis may complicate inherited dermatoses, but recessive dystrophic epidermolysis bullosa (RDEB) complicated by renal amyloidosis is rare. We report a case of a 12-year-old male child with RDEB presenting with progressive generalized anasarca for 20 days. Kidney biopsy showed diffuse expansion of mesangial matrix by pale acellular Periodic Acid-Schiff (PAS)-negative amorphous material, which was congophilic on Congo red stain and gave apple green birefringence on polarization and extending along the glomerular basement membrane, suggestive of amyloidosis. Genetic analysis showed a compound heterozygous pathogenic variant in the COL7A1 gene with autosomal recessive inheritance.