Systemic autoimmune abnormalities complicated by cytomegalovirus-induced hemophagocytic lymphohistiocytosis: A case report.

Background: Hemophagocytic lymphohistiocytosis (HLH) is a rare but life-threatening disorder, characterized by a hyperimmune response. The mortality is high despite progress being made in the diagnosis and treatment of the disease. HLH is traditionally divided into primary (familial or genetic) and secondary (reactive) according to the etiology. Secondary HLH (sHLH), more common in adults, is often associated with underlying conditions including severe infections, malignancies, autoimmune diseases, or other etiologies.

Case Summary: The case involves a 31-year-old woman, presented with a high persistent fever, rash, and splenomegaly. She met the diagnostic criteria of the HLH-2004 guideline and thus was diagnosed with HLH, with positive anti-nuclear antibody (ANA) and positive cytomegalovirus (CMV)-DNA. The patient responded well to a combination of immunomodulatory, chemotherapy, and supportive treatments. When her PCR evaluation for CMV turned negative, her serum ferritin also dropped significantly. Her clinical symptoms improved dramatically, and except for ANA, the abnormal laboratory findings associated with HLH returned to normal. Our previous study has shown that the median overall survival of HLH patients is only 6 mo; however, our patient has been cured and has not presented with any relapse of the disease for 6 years.

Conclusion: This case emphasizes that thorough early removal of the CMV infection is significant for the prognosis of this HLH patient.