STI, HIV, and COVID-19 Screening ICD-10-CM codes

Z11.3 (screening for infections with a predominantly sexual mode of transmission) is the diagnosis for routine chlamydia, gonorrhea, and syphilis testing (87491, 87591, 86780) in a patient with no symptoms and no known exposure. HIV screening is Z11.4, billed with 86703 or 87389, or G0475 for Medicare, which covers annual screening under Z11.4 for ages 15 to 65 and for anyone at increased risk. Hepatitis B and C screening use Z11.59 (other viral diseases); Medicare pays hepatitis C screening under G0472 with Z11.59. HPV screening is Z11.51.

Screening and exposure are different encounters. A patient tested because a partner has a diagnosed STI has a known exposure and is coded Z20.2 (contact with and suspected exposure to STIs), not Z11.3; a patient with discharge or dysuria has symptoms and is coded to the symptom. The same logic applies to COVID-19: Z11.52 is for screening an asymptomatic patient with no known exposure, including the pre-procedure test, while Z20.822 is for a documented or suspected exposure. A symptomatic patient without a confirmed result is coded to the symptoms (R05.9, R50.9) with Z20.822, and a confirmed case is U07.1.

Z72.51, Z72.52, and Z72.53 (high-risk sexual behavior) are reported as secondary codes when documented and are what most payers, including Medicare, look for to cover STI and HIV screening more than once a year. HIV counseling given as its own service is Z71.7, and positive screens are recoded to the confirmed infection (A74.9, A54.x, B20) on the follow-up visit.

Z86.16 records a personal history of COVID-19 in a patient who has recovered, and Z28.310 and Z28.311 report unvaccinated or partially vaccinated status. None of the Z11 or Z20 codes should be reported once the infection is confirmed; they describe the reason for testing, not the result.