Suppurative pyogenic reactions develop. Infections are typically acute and fulminant. Gastrointestinal Usually affects patients with severe malnutrition May involve the stomach, ileum, and colon Clinical picture mimics intra-abdominal abscess. The prognosis is grave, especially when the rhinocerebral area is involved in patients with uncontrolled diabetes. Most cases of gastric and pelvic disease are diagnosed at autopsy.
Many cases occur in patients with pulmonary disease, leukemia, or with lymphomas.
These are usually fatal. The tissue reaction is usually slight. Acute suppurative inflammation predominates with focal areas of granulomatous inflammation. Hyphae usually vary from 6-50 um in diameter, are sparsely septate, and irregularly branched. The organism characteristically invades the walls of adjacent blood vessels, producing thrombosis and infarction, but rarely disseminates through the vessels.