How should Admitting Diagnosis relate to Principal Diagnosis in coding?

• A. Admitting diagnosis is the reason for admission at the time of admission; ensure it is the same or appropriately supported as the principal diagnosis.
• B. Admitting diagnosis must always be coded as a higher priority than principal diagnosis.
• C. The admitting diagnosis is unrelated to the principal diagnosis.
• D. Admitting diagnosis can be used as the sole diagnosis for coding.

Answer: (A)

Admitting diagnosis represents the reason for admission noted at the time of entry to the hospital, while the principal diagnosis is the condition identified after evaluation that most directly caused the admission and subsequent inpatient care. The best practice is to have the admitting diagnosis equal to or supported by the principal diagnosis. If the final assessment reveals a different main condition, the principal diagnosis should reflect that actual reason for admission, with the admitting diagnosis still documented as the presenting reason and tied to the chart evidence.

For example, a patient is admitted with chest pain (admitting diagnosis); after tests, the principal diagnosis is acute myocardial infarction. This remains valid because chest pain was the presenting reason for admission and is supported by the final diagnosis. The admitting diagnosis is not prioritized over the principal diagnosis, it is not unrelated, and it should not be used as the sole diagnosis for coding—the principal diagnosis (and any other relevant conditions) must be documented for accurate coding.