Primary intramuscular cold abscess in the left deltoid region: a case report.

A case of primary intramuscular cold abscess in the left deltoid region is described. There was no underlying bone lesion in relation to cervical or thoracic spine, shoulder joint or upper humerus, and clavicle. It is postulated that the cold abscess might have developed as a result of reactivation of BCG lesion when the patient received a fresh dose of tubercular bacilli which produced only lymph node enlargement in the mediastinum because of the partial immunity the patient had.