[Pathogen Identification for An Imported Case with African Trypanosomiasis].

ABSTRACT

Objective: To perform laboratory diagnosis for an imported case of human African trypanosomiasis and identify the pathogen. Methods: Clinical and epidemiological information was collected. Blood and cerebrospinal fluid samples were collected, stained with Wright-Giemsa, and microscopically examined. Genomic DNA from the blood samples was amplified with primers specific for Trypanosoma sp. expression site-associated gene (ESAG), Trypanosoma brucei gambiense specific glycoprotein (TgsGP) and 18S rRNA（M18S-Ⅱ-Tb） gene, and Trypanosoma brucei rhodesiense specific serum resistance associated （SRA） gene. Complete blood count, blood chemistry, and CSF examination were also conducted. Results: The patient had a 4-month history of lower extremity weakness and swelling of surface lymph nodes. Physical examination showed somnolence, and occasional emotional abnormalities, accompanied by anemia (hemoglobin 85 g/L), electrolyte disturbance (sodium 124 mmol/L; chlorine 87 mmol/L) and significantly increased nonspecific immune globulin protein （globulin 63 g/L）. Epidemiological survey showed that the patient suffered insect bites and stings for several times during his work in the Republic of Gabon in Africa. Microscopic examination revealed flagella of trypanosome in peripheral blood. PCR amplification produced bands of 286, 308, and 150 bp with primers specific for ESAG, TgsGP and M18S-Ⅱ-Tb, respectively. Conclusion: The patient was diagnosed with Trypanosoma brucei gambiense infection from the clinical information, epidemiological history, etiology and PCR results.