During the first wave of the COVID�19 pandemic, a patient with anti-synthetase syndrome (ASS) was misdiagnosed as having bilateral severe acute respiratory syndrome coronavirus 2 pneumonia on admission. A comprehensive clinical evaluation would have led to the correct diagnosis earlier, as he had some data consistent with ASS on both physical examination and laboratory tests that were initially overlooked. In addition, a malignant lesion in the colon was found on screening for underlying malignancy. In this context, ASS has been considered a low-risk subgroup for cancer among idiopathic inflammatory myopathies. However, this should be interpreted cautiously and should not lead to neglect of adequate cancer screening adjusted for age, sex and other potential risk factors.
Keywords: COVID-19; anti-synthetase syndrome; cancer screening; clinical reasoning; interstitial pneumonitis.