Inflammation of the bursae may also be caused by other inflammatory conditions such as rheumatoid arthritis, scleroderma, systemic lupus erythematosus, and gout. Immune deficiencies, including HIV and diabetes, can also cause bursitis. Infrequently, scoliosis can cause bursitis of the shoulders; however, shoulder bursitis is more commonly caused by overuse of the shoulder joint and related muscles.Traumatic injury is another cause of bursitis. The inflammation irritates because the bursa no longer fits in the original small area between the bone and the functionary muscle or tendon. When the bone increases pressure upon the bursa, bursitis results. Sometimes the cause is unknown. It can also be associated with various other chronic systemic diseases. Diagnosis
Types
The most common examples of this condition:
Prepatellar bursitis, "housemaids knee"
Infrapatellar bursitis, "clergymans knee"
Trochanteric bursitis, giving pain over lateral aspect of hip
Olecranon bursitis, "students elbow", characterised by pain and swelling in the elbow
Subacromial bursitis, giving shoulder pain, is the most common form of bursitis. Achilles bursitis
Retrocalcaneal bursitis
Ischial bursitis, "weavers bottom"
Iliopsoas bursitis
Anserine bursitis

Treatment
It is important to differentiate between infected and non-infected bursitis. People may have surrounding cellulitis and systemic symptoms include a fever. The bursa should be aspirated to rule out an infectious process.Bursae that are not infected can be treated symptomatically with rest, ice, elevation, physiotherapy, anti-inflammatory drugs and pain medication. Since bursitis is caused by increased friction from the adjacent structures, a compression bandage is not suggested because compression would create more friction around the joint. Chronic bursitis can be amenable to bursectomy and aspiration. Bursae that are infected require further investigation and antibiotic therapy.
Other nephrotoxic drugs should be avoided. Nephrotoxicity is usually reversible and can be reduced by dosage adjustment and adequate hydration. Electrolyte disturbances — hypocalcemia and hypomagnesemia can occur and regular monitoring of electrolytes is necessary to avoid clinical toxicity. Genital ulceration — a less common reported side effect which occurs more in men and usually during induction use of foscarnet. It is most likely a contact dermatitis due to high concentrations of foscarnet in urine. It usually resolves rapidly following discontinuation of the drug. CNS — less common side effects of perioral paresthesia, irritability and altered mental states. References
Sources
Dennis L. Kasper, Eugene Braunwald. "Harrisons Manual of Medicine", 16th Edition, Mcgraw-hill, (2005), p. 2244. External links
"Foscarnet". Drug Information Portal. U.S. National Library of Medicine. "Foscarnet sodium". Drug Information Portal. U.S. National Library of Medicine.