Fetal plasma carbonic anhydrase III and creatine kinase in Duchenne dystrophy

Serum carbonic anhydrase III in myotonic dystrophy

Serum carbonic anhydrase III (CAIII) levels were determined by means of an enzyme immunoassay method and were compared with serum creatine kinase (CK) and muscle-specific enolase (MSE) levels in 33 patients with myotonic dystrophy. Serum CAIII levels were elevated in all 33 patients, whereas serum CK and MSE levels were elevated in 12 and 10 patients, respectively. Serum CAIII levels showed a good correlation with CK levels, but a poor one with MSE levels. There was no obvious correlation between the serum CAIII level and the duration of illness or the age of the patient. These results suggest that serum CAIII is probably a more sensitive marker than CK and MSE in myotonic dystrophy and may also reflect the type 1 fiber abnormality more predominantly observed in myotonic dystrophy.

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.