Acute kidney injury and inflammatory immune reconstitution syndrome in mixed genotype (A/E) hepatitis B virus co-infection in HIV-associated lymphoma.

We report a first case of HIV-associated lymphoma (HAL) presenting with acute kidney injury (AKI) and inflammatory immune reconstitution syndrome (IRIS). A 39-year-old male, treated with nonsteroidal anti-inflammatory drugs (NSAIDs) for one month prior to admission, developed AKI, left testicular tumor, and recurrent swelling of the right parotid gland. A resected testicular tumor exhibited features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma. Renal biopsy showed hydro-degeneration of renal tubules, interstitial inflammatory cells, and a small number of lymphoma cells in the sub-capsule, compatible with acute interstitial nephritis. His renal dysfunction rapidly recovered following chemotherapy and combination antiretroviral therapy (cART). He developed pneumonia concomitantly with a decrease in HIV-RNA level and an increase in CD4+ cells after the first cycle of chemotherapy, which spontaneously resolved after the second cycle of chemotherapy without additional anti-infection drugs; thus, his pneumonia fulfilled the diagnostic criteria for IRIS. We suggest that IRIS may frequently develop during chemotherapy for HAL, but may be overlooked. He was coinfected with hepatitis B virus (HBV), which genotypes known as is associated with liver-related mortality and response to antiviral therapy; recently, an intimate interplay between HIV and HBV in the onset of lymphoma has been reported. Therefore, we addressed the HBV genotype in the patient. The analysis revealed that he exhibited a mixed genotype (A/E) not native to Japan and primarily found in Europe and North America or West Africa. These findings suggest that universal vaccination for juveniles against HBV is warranted in Japan.