Background: The aim of this study was to evaluate the frequency of appearance of myopathy in a group of patients treated with zidovudine.
Methods: A prospective study of 37 patients with positive serology for HIV treated over 180 days with zidovudine was carried out with evaluation of the clinical history, physical examination and analytical data.
Results: The initial mean value of creatine kinase of 76.4 U/l and 83.3 U/l following 6 months of treatment was not statistically significant. Of the 37 patients, 2 (5.4%) showed no variations in CK values, while in 4 (10.8%) there was a decrease and in 30 (81%) an increase. There was an elevation in 11 of the 15 patients (73%) who received doses equal to or lower than 90 g, 11 out of 13 (84.6%) of those who received between 90 and 145 g and 8 out of 8 (100%) of those having received doses higher than 145 g. This increase was minimum in 27 cases (92%) and important with final values of pathologic CK in 3 (8%). Two patients (5.4%) developed clinical manifestations.
Conclusions: Not only the frequency and range of creatine kinase elevation but also the appearance of clinical manifestations in this study are lower than those found in the literature, probably because of the relation with the use of lower doses of zidovudine. These results do not demonstrate any relation with sex, age, risk group for the immunodeficiency status.