Case report 668. Carbonic anhydrase II deficiency syndrome (osteopetrosis associated with renal tubular acidosis and cerebral calcification).
A 4-month-old infant with bronchiolitis was found to have hyperdense bones on chest roentgenograms. The diagnosis of osteopetrosis was demonstrated by generalized increased radiological bone density and by a bone biopsy showing persistence of calcified cartilage. The infant also had a mixed proximal and distal renal tubular acidosis requiring as much as 12 mEq/kg per day of sodium bicarbonate. Measurement of his erythrocyte carbonic anhydrase activity revealed a deficiency of CA II. His parents showed values of CA activity that were intermediate between controls and the proband. Thus, this is a patient with the CA II deficiency syndrome; he is the youngest reported case without any family history of osteopetrosis to be diagnosed initially on the basis of his radiographic features.
Department of Pediatrics, Montefiore Medical Center, Bronx, New York.
G J
GJ
Schwartz
L P
LP
Brion
H E
HE
Corey
H D
HD
Dorfman
D000141:Acidosis, Renal Tubular / Q000235:genetics*; D001927:Brain Diseases / Q000235:genetics*; D002114:Calcinosis / Q000235:genetics*; D002256:Carbonic Anhydrases / Q000172:deficiency*; D005808:Genes, Recessive; D006801:Humans; D007223:Infant; D008297:Male; D010022:Osteopetrosis / Q000000981:diagnostic imaging / Q000235:genetics*; D011859:Radiography; D013577:Syndrome
D002256:Carbonic Anhydrases