5.3.3 Visceral leishmaniasis

Visceral leishmaniasis, sandfly-mediated systemic infection of Leishmania donovani, kills more than 20,000 persons in 2015 but has been classified by the World Health Organization as a neglected tropical disease [76]. A Japanese businessman aged 30's stayed in a sequential order in Australia, Thailand, Singapore, and finally India [77]. During his stay in India, he manifested headache, high fever, thrombocytopenia, and liver dysfunction. The patient was hospitalized in Japan, but his general condition was poor. In order to confirm the diagnosis, liver biopsy was performed. Small epithelioid granulomas were identified, and the possibility of Q fever in Australia, melioidosis in Thailand, brucellosis, miliary tuberculosis, and non-tuberculous mycobacteriosis was considered histopathologically. No positive findings were obtained in immunohistochemical analysis using a panel of antibodies. The patient's own serum diluted at 1:500 demonstrated red cell-sized positive signals in the cytoplasm of epithelioid cells (Figure 48) [7, 8, 21, 23, 77]. The size and shape of the pathogen strongly suggested visceral leishmaniasis (kala azar) endemic in India. High serum immunofluorescence titer against L. donovani was serologically confirmed thereafter. Administration of pentavalent antimony compound saved his life. This is the real case, in which immunostaining using the patient's own serum was practical maximally.
