Hereditary haemochromatosis, haemophagocytic lymphohistiocytosis and COVID-19

•Bi-phasic illness observed in COVID 19 leading to ARDS after week two of illness.•Haemochromatosis compromises host defence mechanisms and predisposes to infection.•Excess iron may increase SARS-CoV-2 replication leading to a hyperinflammatory state.•Hepatotoxicity may have been exacerbated by Anakinra with COVID-19 and HLH. Syndromes of iron overload have been shown to increase the risk of severe clinical disease in viral infections. Immune dysfunction is similarly described in hereditary haemochromatosis (HH). We present here the case of a 51-year-old man who developed severe coronavirus disease 2019 (COVID-19) complicated by suspected haemophagocytic lymphohistiocytosis (HLH). He was found to have HH post-mortem and we propose a link between his iron overload and the development of severe COVID-19. The initial clinical presentation consisted of cough, shortness of breath and fever. Pancytopenia, markedly elevated ferritin and d-dimer were present. Computed tomography (CT) showed bilateral ground glass changes consistent with COVID-19, widespread lymphadenopathy and splenomegaly. A subsequent combined nose and throat swab was positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). HLH was suspected based upon the H-score and Anakinra, an IL-1 receptor antagonist, was commenced. Liver function acutely worsened and magnetic resonance cholangiopancreatography (MRCP) revealed hepatic haemosiderosis. Intense splenic and cervical lymph node uptake were seen on a positron emission tomography (PET) scan and high doses of intravenous steroids were administered due to concerns over haematological malignancy. Day fourteen of admission heralded the start of progressive clinical deterioration with rapid increase in oxygen demands. Continuous positive airway pressure (CPAP) was trialled without success and the patient unfortunately died seventeen days into admission. Results returned after his death showed homozygous C282Y mutation of the HFE gene consistent with a diagnosis of HH. Post-mortem examination revealed widespread haemosiderin deposition in the liver along with lung pathology in keeping with severe COVID-19 and widespread splenic infarctions. An association between HH and COVID-19 is not currently described in the literature. What does exist, however, is an evidence base for the detrimental impacts iron overload has on viral infections in general and the negative effects of HH on the immune system. We therefore postulate that the underly