Successful Management of a Left-Sided Endocarditis Patient Complicated with Hemophagocytic Lymphohistiocytosis---a Rare Case Report and Literature Review

Objective: To increase the knowledge and experience of treating left-sided endocarditis patients complicated with hemophagocytic lymphohistiocytosis.

Method: One case with left-sided endocarditis and secondary hemophagocytic lymphohistiocytosis was reported and related PubMed literatures were reviewed.

Results: A 40-year-old Asian female came to hospital with uncontrolled repeated fever that had lasted for more than one month. Prior to this admission, the patient suffered a sub-acute liver failure of unknown cause and received artificial liver support and intravenous hepatic protectants in the local hospital, and the patient responded well. At that time echocardiography revealed congenital heart disease. After admission to our hospital, her lab results showed pancytopenia, coagulation abnormal and significantly elevated levels of total bilirubin, soluble CD25 and serum ferritin. Bone marrow biopsy was negative for hemaphagocytosis. The full body PET-CT was performed and the results demonstrated hepato-splenomegaly and relatively increased standard uptake value (SUV) of the spleen, with no signs of malignancies. Several sets of blood cultures were all positive for methicillin-resistant Staphylococcus epidermidis (MRSE). Two weeks later, cardiac ultrasound images were obtained and showed a completely well-shaped vegetation attached to the aorta valve, which confirmed the diagnosis of definite infectious endocarditis (IE). So the final diagnosis was the MRSE-related left-sited infectious endocarditis and acquired HLH. The Multi-disciplinary team (MDT) discussed this critical case, since the allergic reaction of vancomycin and no therapeutic effect of tecolplanin for 10 days, the patient was treated by high dose daptomycin(10 mg/kg once daily) and chemotherapy according to HLH-2004 protocol, afterwards the patient's condition was improved, cardiothoracic surgery was performed smoothly and the vegetation on the aortic valve was successfully removed. Till now the patient has been in good condition for more than 2 years. There are only 4 case reports pertinent to endocarditis with HLH published in PubMed and these related cases were also reviewed.

Conclusion: This case report is the description of another rare and complicated condition in which the patient concurrently developed left-sided infectious endocarditis and acquired HLH. High dose daptomycin monotherapy was effective for controlling MRSE-related left-sided IE. Early diagnosis and intervention is very important for the successful treatment of HLH. Our case also highlights the importance of the multi-disciplinary team (MDT) model in dealing with similar critical cases in the clinic work.