The cause of muscle cramps isn't always known. Muscle cramps may be brought on by many conditions or activities, such as: 1  Exercising, injury, or overuse of muscles. 2  Pregnancy. 3  Cramps may occur because of decreased amounts of minerals, such as calcium and magnesium, especially in the later months of pregnancy.
Causes of Otitis externa. Causes of Otitis externa. Otitis externa is caused by a bacterial or viral infection in the external part of the ear canal. A common bacterial pathogen is Pseudomonas aeruginosa. List of causes of Otitis externa. Otitis externa Causes: Risk Factors.
Otitis means inflammation of the ear. The inflammation is usually due to an infection. Otitis externa means that the inflammation is confined to the external part of the ear canal and does not go further than the eardrum. See separate leaflet called Ear Infection (Otitis Media), for an infection of the middle ear.