As part of the initial visit, the patient undergoes laboratory testing, which includes a complete blood count, comprehensive metabolic profile, lipid profile, urinalysis, viral load, and genotyping for HIV resistance and testing for CD4, hepatitis (including hepatitis A, B, and C), quantiFERON-TB, G6PD (glucose-6-phosphate dehydrogenase), HLA-B5701 (human leucocyte antigen-B5701), toxoplasmosis, RPR (rapid plasma reagin), and sexually transmitted diseases (syphilis, chlamydia, and gonorrhea). The gene discussed is G6PD; the disease is chlamydia trachomatis infectious disease.