Causes of Acquired Myopathies

Acquired muscle diseases are of following types:

1 Inflammatory
2 Endocrine: Thyroid and other diseases
3 Metabolic: Kidney disease, protein deficiency, deficiency of vitamin D (Osteomalacia) or vitamin E
4 Drugs and Toxins: Snake poison, alcohol, pethidine, glucocorticoids, statins and clofibrate (for high cholesterol), chloroquin, colchicin, phenytoin (for epilepsy), zidovudin (for AIDS), vincristin (for cancer) and other drugs
5 Infections: Bacteria, viruses (HIV) and parasites
6 Others: Sarcoidosis, cancer, etc.

Inflammatory muscle diseases (myositis) are due to swelling in the bundles of muscle fibers.