Medical Coding Quiz For Certain Infectious and Parasitic Diseases (A00-b99)

Asymptomatic human immunodeficiency virus
Z21. Asymptomatic human immunodeficiency virus [HIV] infection status, is to be applied when the patient without any documentation of symptoms is listed as being "HIV positive," "known HIV," "HIV test positive." or similar terminology. Do not use this code if the term "AIDS" is used or if the patient is treated for any HIV-related illness or is described as having any condition(s) resulting from his/her HIV positive status; use B20 in these cases.

Combination codes for MRSA infection
When a patient is diagnosed with an infection that is due to methicillin resistant Staphylococcus aureus (MRSA), and that infection has a combination code that includes the causal organism (e.g., sepsis, pneumonia) assign the appropriate combination code for the condition (e.g., code A41.02, Sepsis due to Methicillin resistant Staphylococcus aureus or code J15.212, Pneumonia due to Methicillin resistant Staphylococcus aureus). Do not assign code B95.62, Methicillin resistant Staphylococcus aureus infection as the cause of diseases classified elsewhere, as an additional code because the combination code includes the type of infection and the MRSA organism. Do not assign a code from subcategory Z16.11, Resistance to penicillins, as an additional diagnosis.
See Section C. 1 for instructions on coding and sequencing of sepsis and severe sepsis.

Encounters for testing for HIV
If a patient is being seen to determine his/her HIV status, use code Z11.4, Encounter for screening for human immunodeficiency virus [HIV]. Use additional codes for any associated high risk behavior.
If a patient with signs or symptoms is being seen for HIV testing, code the signs and symptoms. An additional counseling code Z71.7, Human immunodeficiency virus [HIV] counseling, may be used if counseling is provided during the encounter for the test.
When a patient returns to be informed of his/her HIV test results and the test result is negative, use code Z71.7, Human immunodeficiency virus [HIV] counseling.
If the results are positive, see previous guidelines and assign codes as appropriate.

Sepsis with organ dysfunction
If a patient has sepsis and associated acute organ dysfunction or multiple organ dysfunction (MOD), follow the instructions for coding severe sepsis.

Infectious agents as the cause of diseases classified to other chapters
Certain infections are classified in chapters other than Chapter 1 and no organism is identified as part of the infection code. In these instances, it is necessary to use an additional code from Chapter 1 to identify the organism. A code from category B95, Streptococcus, Staphylococcus, and Enterococcus as the cause of diseases classified to other chapters, B96, Other bacterial agents as the cause of diseases classified to other chapters, or B97, Viral agents as the cause of diseases classified to other chapters, is to be used as an additional code to identify the organism. An instructional note will be found at the infection code advising that an additional organism code is required.

MRSA colonization and infection
If a patient is documented as having both MRSA colonization and infection during a hospital admission, code 122.222. Carrier or suspected carrier of Methicillin resistant Staphylococcus aureus, and a code for the MRSA infection may both be assigned

Encounters for testing for HIV
If a patient is being seen to determine his/her HIV status, use code Z11.4, Encounter for screening for human immunodeficiency virus [HIV]. Use additional codes for any associated high risk behavior.
If a patient with signs or symptoms is being seen for HIV testing, code the signs and symptoms. An additional counseling code Z71.7, Human immunodeficiency virus [HIV] counseling, may be used if counseling is provided during the encounter for the test.
When a patient returns to be informed of his/her HIV test results and the test result is negative, use code Z71.7, Human immunodeficiency virus [HIV] counseling.
If the results are positive, see previous guidelines and assign codes as appropriate.

Selection and sequencing of HIV codes
(a) Patient admitted for HIV-related condition
If a patient is admitted for an HIV-related condition, the principal diagnosis should be B20. Human immunodeficiency virus [HIV) disease followed by additional diagnosis codes for all reported HIV-related conditions.

Postprocedural infection and postprocedural septic shock
In cases where a postprocedural infection has occurred and has resulted in severe sepsis, the code for the precipitating complication such as code T81.4, Infection following a procedure, or 086.0, Infection of obstetrical surgical wound should be coded first followed by code R65.20, Severe sepsis without septic shock. A code for the systemic infection should also be assigned.
If a postprocedural infection has resulted in postprocedural septic shock, the code for the precipitating complication such as code T81.4, Infection following a procedure, or 086.0, Infection of obstetrical surgical wound should be coded first followed by code T81.12-, Postprocedural septic shock. A code for the systemic infection should also be assigned.

Acute organ dysfunction that is not clearly associated with the sepsis
If a patient has sepsis and an acute organ dysfunction, but the medical record documentation indicates that the acute organ dysfunction is related to a medical condition other than the sepsis, do not assign a code from subcategory R65.2, Severe sepsis. An acute organ dysfunction must be associated with the sepsis in order to assign the severe sepsis code. If the documentation is not clear as to whether an acute organ dysfunction is related to the sepsis or another medical condition, query the provider.