Imported malaria in a Japanese male: an autopsy report.

Fatal cases of malaria are rare in Japan. We report a case of a 47-year-old Japanese man with Plasmodium falciparum malaria. The patient was examined because of fever and headache after a trip to Africa. He was diagnosed with malaria. Chemotherapy begun on day three decreased the percentage of infected red blood cells (RBC) from 25% to 2%, but the patient fell into coma on the same day. The patient was considered brain dead for 3 days before he died, and he was autopsied on day nine. Brain hemispheres were preserved and swollen with meningeal congestion. The ventral area of the pons and medulla oblongata were softened, and the tonsils of the cerebellum were softened and herniated. The spleen was blackish, enlarged and showed a small infarction. The liver was yellowish and enlarged. Many infected RBC were seen in the capillaries of the brain and malaria pigments were seen in the spleen and liver. DNA of P. falciparum was detected by polymerase chain reaction from paraffin-embedded brain materials, however, the DNA could not be detected in other organs. Besides malaria, the patient had latent primary thyroid cancer, which was a small and invasive papillary carcinoma.