title: Combined Alport syndrome and Klinefelter syndrome.
abstract: To date, there have been a very limited number of case reports on combined Alport syndrome (AS) and Klinefelter syndrome (KS). We herein describe the case of a 9-month-old boy diagnosed with concomitant AS and KS. KS was detected on chromosomal analysis of the amniotic fluid, and hematuria/proteinuria was identified in urinary screening at 6 months of age. Renal biopsy indicated AS, with complete deficit of the α5 chain of type IV collagen in the glomerular basement membranes. On genetic analysis for AS, de novo homozygote mutation (c.3605-2a > c) was seen in the gene encoding α5 chain of type IV collagen (COL4A5) on the X chromosomes of maternal origin. This is the first case report of combined AS and KS diagnosed during infancy, and it indicates the need to consider the concurrent existence of these two disorders in infants with urine abnormalities, even in the absence of a family history.
authors.affiliation: Department of Pediatric Cardiology and Nephrology, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kyoto, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Nishida
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Fusako
authors.initials: F
authors.lastname: Hashimoto
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kaito
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Kandai
authors.initials: K
authors.lastname: Nozu
authors.affiliation: Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Kazumoto
authors.initials: K
authors.lastname: Iijima
authors.affiliation: Department of Pediatric Cardiology and Nephrology, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kyoto, Japan.
authors.forename: Dai
authors.initials: D
authors.lastname: Asada
authors.affiliation: Department of Pediatric Cardiology and Nephrology, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kyoto, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Hamaoka
mesh_terms: D057911:Angiotensin Receptor Antagonists / Q000627:therapeutic use; D001713:Biphenyl Compounds / Q000627:therapeutic use; D024141:Collagen Type IV / Q000235:genetics; D006801:Humans; D007223:Infant; D000077405:Irbesartan; D007668:Kidney / Q000473:pathology*; D007713:Klinefelter Syndrome / Q000150:complications*; D008297:Male; D009154:Mutation; D009394:Nephritis, Hereditary / Q000150:complications* / Q000175:diagnosis / Q000188:drug therapy; D013777:Tetrazoles / Q000627:therapeutic use
chemical_list: D057911:Angiotensin Receptor Antagonists; D001713:Biphenyl Compounds; D024141:Collagen Type IV; D013777:Tetrazoles; D000077405:Irbesartan
keywords: Alport syndrome; Klinefelter syndrome; chromosomal abnormality; extra X chromosome; infant