Primary Care Coding Alert

Question: If a provider tests a patient for a sexually transmitted disease (STD), but the patient has no symptoms, should I use A64 for a diagnosis?

Michigan Subscriber

Answer: You should use A64 (Unspecified sexually transmitted disease) only if your provider documents that the patient actually has an STD and if there is no other documentation or specific code for the particular STD your provider has diagnosed.

If the patient is asymptomatic, however, you should regard the test as a screening and assign it the appropriate Z code. You would use Z11.3 (Encounter for screening for infections with a predominantly sexual mode of transmission) unless the provider was screening for human immunodeficiency virus (HIV) or human papillomavirus (HPV), which have their own separate encounter codes: Z11.4 (Encounter for screening for human immunodeficiency virus [HIV]) and Z11.51 (Encounter for screening for human papillomavirus (HPV)).

Depending on your physician’s documentation, other encounter codes such as the contact and suspected exposure codes Z20.6 (Contact with and (suspected) exposure to human immunodeficiency virus [HIV]), Z20.828 (Contact with and (suspected) exposure to other viral communicable diseases), and Z20.89 (Contact with and (suspected) exposure to other communicable diseases), or codes such as Z72.5- (High risk sexual behavior) or Z70.- (Counseling related to sexual attitude, behavior and orientation) may come into play in this scenario.