A Japanese family with Alport syndrome associated with esophageal leiomyomatosis: genetic analysis of COL4A5 to COL4A6 and immunostaining for type IV collagen subtypes.
BACKGROUND
In some families, X-linked Alport syndrome (AS) is associated with diffuse leiomyomatosis. We describe clinical, pathologic and molecular-genetic findings in a Japanese family with this inheritance mode of AS in association with leiomyomatosis.


METHODS
AS was diagnosed in a one-year-old boy with recurrent aspiration pneumonia caused by esophageal stenosis from leiomyomatosis. Diagnosis was confirmed by electron microscopy coupled with type IV collagen chain subtype staining in a renal biopsy specimen. His mother, who exhibited esophageal leiomyomatosis and is heterozygous for AS, showed a discontinuous staining pattern for collagen alpha5(IV) chain along the epidermal basement membrane in a skin biopsy specimen. Genetic analysis in the boy revealed the deletion of the first two exons of COL4A6 together with deletion of the 5' end of COL4A5. Despite administration of cyclosporin A, massive proteinuria has persisted in the boy, although renal function otherwise remains normal.


CONCLUSIONS
Identification of an AS patient during infancy is extremely rare. Clinical manifestations, including macroscopic hematuria, cataracts and leiomyomatosis caused by the large deletion involving COL4A5 to COL4A6, led to early presentation with AS.
Sugimoto
K
K
Department of Pediatrics, Kinki University School of Medicine, Ohno-higashi, Osaka-Sayama, Japan.
Yanagida
H
H
Yagi
K
K
Kuwajima
H
H
Okada
M
M
Takemura
T
T
D024141:Collagen Type IV / Q000235:genetics*; D004252:DNA Mutational Analysis; D004935:Esophageal Diseases / Q000150:complications / Q000235:genetics*; D005260:Female; D006801:Humans; D007223:Infant; D007564:Japan; D018231:Leiomyomatosis / Q000150:complications / Q000235:genetics*; D008297:Male; D008854:Microscopy, Electron; D005810:Multigene Family; D009394:Nephritis, Hereditary / Q000150:complications / Q000235:genetics*; D016133:Polymerase Chain Reaction
D024141:Collagen Type IV