Even though the current patient was diagnosed with SLE per the 2019 American College of Rheumatology criteria, sensitivity of 96% and specificity of 93%, by fulfilling the entry criterion of having a positive ANA test in addition to arthralgia, fever, thrombocytopenia, seizure, pleural effusion, and a low C4 level [9]. This evidence concerns the gene C4A and Pleural effusion.