Primary Care Coding Alert

Question: One of our physicians diagnosed a patient who is four weeks pregnant with HIV. She has not experienced any HIV-related conditions. Which ICD-10 codes are appropriate for this encounter?

Indiana Subscriber

Answer: The proper coding for this is as follows:

• O98.711 (Human immunodeficiency virus (HIV) disease complicating pregnancy, first trimester)
• Z21 (Asymptomatic human immunodeficiency virus (HIV) infection status)
• Z3A.01 (Less than 8 weeks gestation of pregnancy)

In this encounter, the physician saw a patient in their first trimester of pregnancy. Code O98.711 from ICD-10 chapter 15: Pregnancy, Childbirth, and the Puerperium is sequenced first. To understand why, take a look at ICD-10 Guideline I.C.15.a.1, which says, “Chapter 15 codes have sequencing priority over codes from other chapters. Additional codes from other chapters may be used in conjunction with chapter 15 codes to further specify conditions.” Take note of the 6th character (1), which indicates the patient is in the first trimester.

ICD-10 O98.7- (Human immunodeficiency virus [HIV] disease complicating pregnancy, childbirth and the puerperium) includes a note to use an additional code to identify the type of HIV disease. Because the patient neither has any symptoms of HIV nor is there documentation of any past HIV-related illnesses, you would report code Z21 second. You would use the final code for this scenario to report the weeks of gestation, which supports the 6^th character of “1” in O98.711 indicating the patient is in the first trimester.