Acute fibrinous and organizing pneumonia complicated with hemophagocytic lymphohistiocytosis caused by chronic active Epstein-Barr virus infection: a case report

BACKGROUND: Acute fibrinous and organizing pneumonia (AFOP) is a rare lung condition that is associated with acute lung injury. Its etiology may be idiopathic or secondary to a series of conditions, including immune-related diseases, unclassified connective tissue diseases, hematopoietic stem cell transplantation, infections, hematological diseases and drug induced lung toxicity. We report for the first time a case of AFOP complicated with hemophagocytic lymphohistiocytosis (HLH) caused by chronic active Epstein-Barr virus (CAEBV) infection. CASE PRESENTATION: A 64-year-old man was admitted with a complaint of fever and dyspnea for 2 weeks. The patient presented with elevated serum aminotransferase levels, splenomegaly, progressive decrease of red blood cells and platelets, hyperferritinemia, hypofibrinogenemia, and elevated of Soluble interleukin-2 receptor (sCD25). His chest computed tomography (CT) scan revealed multiple patchy consolidation in both lungs and multiple lymphadenopathy in the mediastinum and hilum. The serology for antibodies of VCA-IgG was positive, EBV-DNA in peripheral blood was elevated, and EBV nucleic acid was detected in the alveolar lavage fluid. Histopathology of the lung tissue showed a dominant of intra-alveolar fibrin and organizing pneumonia. Hemophagocytic cells was found in the bone marrow smear and biopsy. EBV-DNA was detected in lung tissue and bone marrow using in situ hybridization with an EBV-encoded RNA (EBER) probe. After 50 days of hospitalization, he was improved in lung and hemogram. CONCLUSION: We report a case of AFOP with HLH caused by CAEBV in an immunocompetent adult, suggesting that AFOP may be a rare but serious complication caused by CAEBV, and glucocorticoid therapy may improve short-term prognosis.