[Osteopetrosis and renal acidosis: a new case of this rare syndrome].

The association between osteopetrosis and renal acidosis is not accidental, but represents a well-known syndrome with autosomal recessive transmission, due to carbonic anhydrase II(CA II) deficiency. The disease is extremely rare (only few reports in the literature). The diagnosis is confirmed by CA II erythrocyte assay. However, this finding is not essential when the clinical picture is complete, as in the case reported in this paper, which presents a patient with osteopetrosis, proximal tubular acidosis, intracranial calcifications, psychomotor retardation and short stature. Prenatal diagnosis will rely on the genetic study of DNA by molecular probes, since it is already well-known that the coding gene for CA II is on the long arm of chromosome 8 (8q22).