Thrombocytopenia: A Diagnostic Dilemma and Incidental Detection of Systemic Lupus Erythematosus in a Middle-Aged Asian Male

Systemic lupus erythematosus is a multisystem disorder much more common in females than males due to the effect of the hormone estrogen. There are also specific differences in clinical presentation in men and women. We present a unique case of a 54-year-old middle-aged Asian male presenting with only generalized weakness without other systemic features and with only incidental finding of thrombocytopenia. Notable laboratory values were positive for antinuclear antibody (ANA) and anti-double-stranded DNA (dsDNA), low complement 3 level with normal complement 4 levels, along with severe thrombocytopenia and mild anemia. The patient was eventually diagnosed with systemic lupus erythematosus based on these parameters. Bone marrow biopsy revealed an increased number of megakaryocytes without hypocellular or hypercellular marrow and no dysplasia of cell lines. He was initiated on oral prednisone, and his symptoms recovered remarkably with normalization of lab values upon discharge. The case's importance lies in the fact that the diagnosis of lupus can be missed in male patients with nonspecific clinical features due to certain differences in presentation from females. This diagnosis should be included in the workup of any thrombocytopenia.