There is no accurate fast serological test. Diagnosis relies on identifying Talaromyces marneffei in cultures from clinical specimens such as sputum, blood, skin scrapings, lymph node, and bone marrow, by which time the disease is in the late-stage. Fungi in blood are found in half of case. Non-specific laboratory findings may show evidence of the fungus invading tissue, such as low platelets due to bone marrow infiltration, and elevated transaminases due to liver involvement. Biopsies of skin lesions, lymph nodes, and bone marrow demonstrate the presence of organisms on histopathology. Intracellular and extracellular forms are oval and have a characteristic transverse septum. In culture, colonies are powdery green and produce red pigment; however, cultures are negative in a significant number of cases. Medical imaging may reveal shadows in the lungs. Differential diagnosis The disease can look similar to tuberculosis and histoplasmosis
Talaromycosis
Histoplasmosis
Chromoblastomycosis
Tuberculosis
Conidiobolomycosis
Botryomycosis
Basidiobolomycosis
Phycomycosis