Sexually Transmitted Infection STI ICD-10 Codes
STI ICD-10 codes sit mainly in the A50–A64 block of ICD-10-CM, “Infections with a predominantly sexual mode of transmission.” Chlamydia codes start with A56, gonorrhea with A54, syphilis with A51–A53, genital herpes with A60 and trichomoniasis with A59. HIV is coded separately (B20 or Z21), and screening and exposure visits use Z codes such as…







