What are the causes of proximal muscle pain or weakness?

Causes of proximal muscle pain or weakness 

A. Inflammatory 

• Polymyositis 
• Dermatomyositis 
• Other autoimmune connective tissue diseases 
• Inclusion body myositis 
• Sarcoid 
• Myasthenia gravis 

B. Endocrine

• Hypothyroidism 
• Hyperthyroidism 
• Cushing's syndrome 
• Addison's disease 

C. Metabolic 

• Myophosphorylase deficiency 
• Phosphofructokinase deficiency 
• Hypokalaemia 
• Carnitine deficiency 
• Osteomalacia
• Hypercalcaemia 

D. Genetic 

• Muscular dystrophy

E. Drugs/toxins 

• Alcohol 
• Cocaine 
• Glucocorticoids 
• Statins and fibrates 
• Tumour necrosis factor inhibitors 
• Zidovudine 

F. Infections 

• Viral (HIV, cytomegalovirus, rubella, Epstein-Barr, echo) 
• Parasitic (schistosomiasis, cysticercosis, toxoplasmosis) 
• Bacterial (Clostridium perfringens, staphylococci, tuberculosis, Mycoplasma) 

[ Source: Davidson's principles and practice of medicine 23rd Edition; page 1000]