key: cord-0755272-n6sro4op authors: Takami, Akiyoshi title: Reply to the letter by Gaetano Loscocco, Secondary hemophagocytic lymphohistiocytosis, HScore and COVID-19 date: 2020-05-28 journal: Int J Hematol DOI: 10.1007/s12185-020-02896-9 sha: f673347ed2456b9cc6d6dbf52e10f641af3da1ca doc_id: 755272 cord_uid: n6sro4op nan I acknowledge the kind remarks by Dr. Loscocco regarding my interpretation [1] of a recent paper [2] in which the use of both immunosuppressive therapy and the JAK2 inhibitor for hypercytokinemia due to severe COVID-19 has been proposed. I should have stated that "a recent report by Mehta et al. [2] in which all patients with severe COVID-19 should be assessed for secondary hemophagocytic lymphohistiocytosis (sHLH) in the bone marrow and hyperferritinemia using the HScore", because it is now evident that severe COVID-19 can cause sHLH [3, 4] . However, it should be considered that as implied by Dr. Loscocco and in recent reports [3, 5] , patients with severe COVID-19 may not be in a good enough condition to undertake a bone marrow examination due to their severe condition, thus resulting in difficulty demonstrating hemophagocytosis. Regardless of whether hemophagocytosis is demonstrated or whether the HScore should be used, COVID-19 infection can induce hypercytokinemia associated with marked macrophage activation [6, 7] , thus leading to both organ damage and coagulopathy. I would like to reiterate the potential efficacy of low-dose etoposide monotherapy for patients with severe COVID-19 by compensating for the immunoregulator aberration and macrophage activation. Funding There is no funding involved with the manuscript. Conflict of interest The author reports no potential conflict of interest. Possible role of low-dose etoposide therapy for hemophagocytic lymphohistiocytosis by COVID-19 COVID-19: consider cytokine storm syndromes and immunosuppression SARS-CoV-2 infection associated hemophagocytic lymphohistiocytosis: an autopsy series with clinical and laboratory correlation Tocilizumab for hemophagocytic syndrome in a kidney transplant recipient with COVID-19 Favorable anakinra responses in severe Covid-19 patients with secondary hemophagocytic lymphohistiocytosis The pathogenesis and treatment of the 'Cytokine Storm' in COVID-19 Clinical features of patients infected with 2019 novel coronavirus in Wuhan