Serum carbonic anhydrase III in progressive muscular dystrophy.

Serum carbonic anhydrase III (CA-III) levels were determined by means of an enzyme immunoassay method and compared with serum creatine kinase (CK) and muscle-specific enolase (MSE) levels in 143 patients with four types of progressive muscular dystrophy (PMD), namely, Duchenne muscular dystrophy (DMD), limb-girdle dystrophy, facioscapulohumeral dystrophy and congenital dystrophy. Serum CA-III levels were raised in the majority of patients, especially in those with DMD. In DMD patients, the gradual decline in the CA-III level was observed with age. High correlations were found between CA-III, CK and MSE levels. The frequency of cases with elevated CA-III levels was the same as or greater than that of elevated CK or MSE levels in four types of PMD. These results suggest that serum CA-III may be a useful marker of muscle disease.