Be aware of misdiagnosis tied to COVID-19 focusing: a case report of abciximab-induced alveolar haemorrhage thought to be SARS-CoV-2 in a patient with ST-segment elevation myocardial infarction

Background Early diagnosis of diffuse alveolar haemorrhage (DAH) can be extremely difficult, as the common clinical picture is often attributed to more common clinical conditions. High degree of suspicion is key to diagnosis which can be much more difficult during the coronavirus disease 2019 (COVID-19) pandemic. Case summary A 61-year-old man with inferolateral ST-segment elevation myocardial infarction treated by a stent to the left circumflex artery and intravenous abciximab treatment was started for the high thrombus burden. Two hours later, the patient developed dyspnoea and hypoxaemia. Chest examination revealed diffuse rales over both lung fields. Chest X-ray revealed bilateral diffuse alveolar infiltrates, while the echocardiography was normal. Chest computed tomography (CT) was performed and the 'crazy paving appearance', which is the typical radiological finding of COVID-19, was reported. The patient was considered to be suspected of COVID-19 and was transferred to a quarantine unit. Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) test was obtained and azithromycin and hydroxychloroquine were initiated. 48 h later, 2.6 mmol/L reduction was observed in haemoglobin levels and haemoptysis was developed. After the second negative RT-PCR with an interval of 24 h, CT was repeated and the patient was diagnosed to have abciximab-induced DAH. The patient was later followed up conventionally and discharged after two weeks without additional complications. Discussion DAH and COVID-19 might share common clinical and radiological findings during examination. The physicians must be aware of the high motivation of the COVID-19 pandemic which can lead to misdiagnosis by overlooking other important clinical conditions.