Hemophagocytic lymphohistiocytosis (HLH) is a rare hyperinflammatory syndrome characterized by fever, pancytopenia and splenomegaly. The underlying hemophagocytosis occurs primarily in the bone marrow, liver and lymph nodes. Multiple microbiological agents, including cytomegalovirus, Epstein-Barr virus and Mycobacterium tuberculosis, have been implicated in the pathogenesis of HLH. The present study presents a case of HLH associated with Leuconostoc pseudomesenteroides infection treated successfully with clindamycin. A 33-year-old man presented with recurrent episodes of fever and diarrhea. Upon initial treatment at another hospital (the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China), blood chemistry analysis demonstrated moderate anemia (hemoglobin 88 g/l; reference range, 120.0-160.0), elevated ferritin (1,068.47 mg/l; reference range, 21.81-274.66), total bilirubin (392.4 mmol/l; reference range, 5.1-28.0), conjugated bilirubin (335.7 mmol/l; reference range, 0-10.0), and γ-glutamyl transpeptidase (150 U/l; reference range, 10-60). The patient was treated with antibiotics for suspected pneumonia and cholecystitis, but new symptoms (including diarrhea and inflammatory colitis) started to emerge. The patient was subsequently treated with ganciclovir (5 mg/kg/day for 1 month), but body temperature increased to 41.0°C. Upon transferring to our hospital, the patient had severe anemia (hemoglobin, 39 g/l; red blood cell, 1.61×1012/l; reference range, 4.0-5.5×1012/l). Jaundice was apparent: Total bilirubin, 299.5 mmol/l; conjugated bilirubin, 215.7 mmol/l. The patient was treated with clindamycin (150 mg, taken orally every 12 h for 1 week) and supportive care that included parenteral nutrition. Symptoms rapidly dissipated after the treatment. Blood chemistry analysis 5 days after the first dose of clindamycin revealed substantial improvement in anemia and jaundice. The patient requested discharge for financial reasons, but continued treatment (details not available) at a local hospital (Pengpai Memorial Hospital, Shanwei, China). Upon a visit to our hospital 8 months later, the patient has no notable complaints, with the exception of moderate anemia. The present case suggests that HLH may be associated with L. pseudomesenteroides infection.
Keywords: Leuconostoc pseudomesenteroides; clindamycin; hemophagocytic lymphohistiocytosis; hepatomegaly; hyperbilirubinemia; splenomegaly.