ICD-10 Code for STD Screening
For routine STD screening in asymptomatic individuals, use ICD-10 code Z11.3 (Encounter for screening for infections with a predominantly sexual mode of transmission).
Primary Screening Code
- Z11.3 is the appropriate ICD-10 code for encounters specifically for screening for sexually transmitted infections in asymptomatic patients 1
- This code applies when the patient presents without symptoms and the purpose is preventive screening rather than diagnostic evaluation 2
Related Codes for High-Risk Encounters
When documenting encounters that indicate increased risk for STI/HIV, additional codes may be relevant:
- Z20.2: Contact with and exposure to infections with a predominantly sexual mode of transmission 3
- Z72.52: High-risk homosexual behavior 3
- Z72.53: High-risk bisexual behavior 3
- Z20.6: Contact with and exposure to HIV 3
- Z29.81: Encounter for HIV pre-exposure prophylaxis 3
Important Clinical Context
The distinction between screening and diagnostic testing is critical for proper coding:
- Screening codes (Z11.3) apply only to asymptomatic individuals seeking preventive services 2
- Once symptoms are present, testing becomes diagnostic and requires disease-specific codes 2
- Disease-specific ICD-10 codes (such as A74.9 for chlamydia or A54.9 for gonorrhea) should only be used when infection is confirmed or strongly suspected, not for screening 3, 4
Common Coding Pitfalls to Avoid
- Do not confuse pelvic examination with STD screening: Many patients erroneously believe a Pap test was performed during a routine pelvic exam when it was not 1, 5
- Pap tests are NOT STD screening tests: The CDC explicitly states that Pap tests should not be considered screening tests for STDs 1
- Avoid using unspecified STI codes (A64) for screening: This code has poor positive predictive value (32.0%) and should not be used for screening encounters 4
- Do not use disease-specific codes without laboratory confirmation: ICD-10 codes for specific STIs (chlamydia A74.9, gonorrhea A54.9) have high positive predictive values (87.6% and 85.0% respectively) but should only be used when infection is documented 4
Screening Recommendations by Population
The following populations should receive routine STD screening, all coded with Z11.3:
- All sexually active females aged <25 years should be screened for chlamydia and gonorrhea at least annually 1
- Young sexually active men should be screened routinely, particularly in settings where prevalence is ≥2% 1
- Persons entering correctional facilities should be screened for syphilis, gonorrhea, and chlamydia 1
- Adolescents in institutional settings (schools, Job Corps, community programs) should be screened when prevalence is ≥2% 1
Documentation Considerations
- Administrative data analysis shows that before specific doxy PEP recommendations, most encounters for potentially eligible patients were coded broadly, with Z20.2 being the most common code (78.2% of high-risk encounters) 3
- When doxycycline is prescribed for STI treatment (not screening), the most common associated codes include symptoms of genitourinary system (R30-R39, 28.7%) and diseases of urinary system (N30-N39, 9.9%) 3
- Laboratory confirmation is essential for accurate disease-specific coding, as ICD-10 codes alone have low sensitivity (10.6% for chlamydia, 9.7% for gonorrhea) without laboratory results 4