Diagnosis is done with potassium hydroxide (KOH) preparation in tissue. On light microscopy, there will be broad, ribbon-like septate hyphae with 90 degree angles on branches. KOH wet mount of the black eschar will show aseptate fungal hyphae with right angle branching. Periodic Acid Schiff (PAS) staining will reveal similar broad hyphae in the dermis and cutis. Fungal culture can also confirm the organism. Diagnosis remains difficult due to the lack of laboratory tests as mortality remains high. In 2005, a multiplex PCR test was able to identify five species of Rhizopus and may prove useful as a screening method for visceral mucormycosis in the future. The clinical approach to diagnosis includes radiologic, where more than ten nodules and pleural effusion are associated to pulmonary forms of the disease. In CT, a reverse halo sign is noted. Direct microscopy and histopathology, and cultures remain the gold standards for diagnoses. Zygomycophyta share close clinical and radiological features to Aspergillosis. Invasive procedures such as bronchial endoscopy and lung biopsy may be necessary to confirm pulmonary diagnosis are no validated indirect tests are available. Quantitative polymerase chain reaction to detect serum DNA of the pathogen shows promise.
Zygomycosis
Dermatomycosis
Botryomycosis
Lobomycosis
Phycomycosis
Otomycosis
African histoplasmosis
Histoplasmosis