Chronic pulmonary blastomycosis is primarily an upper lobe disease. The most common x-ray abnormality is a fibronodular appearance in which nodular densities are associated with linear fibrotic streaks. Smooth-walled cavities are often observed, and a single mass lesion resembling carcinoma is not unusual. In patients with persistent unresolved consolidation, other clues to the chronicity of the process, such as fibrosis, calcification, and loss of lung volume, should be sought. The first and often only clinically evident site of infection may be the skin.
Small abscesses are frequently demonstrable if the superficial crust is removed.
There may be central healing that leaves an atrophic scar. Minimal erythema is seen in the surrounding skin. Unless bacterial superinfection occurs, these lesions are not painful or pruritic. Less commonly, small superficial ulcers or subcutaneous nodules, sometimes associated with overlying surface pustules, are present. The spine, pelvis, skull, ribs, and long bones of the extremities are the most common sites of skeletal involvement.