What code should be assigned for patients documented as having MSSA colonization?

The correct code for patients documented as having MSSA (Methicillin-sensitive Staphylococcus aureus) colonization is Z22.321. This code specifically indicates a carrier status for Staphylococcus aureus, which is relevant for a patient who is colonized with this bacterium but does not have an active infection. The Z22 codes are used to denote situations where a person is a carrier of a specific pathogen without any associated disease.

In this case, Z22.321 specifically refers to an MSSA carrier, reflecting the correct classification for colonization as opposed to active disease. This distinction is important in coding practices as it allows for accurate representation of the patient's health status, which is essential for treatment, management decisions, and statistical purposes.

The other options do not correctly represent MSSA colonization. Z22.322 could imply a carrier status for MRSA (Methicillin-resistant Staphylococcus aureus), while B95.62 and Z16.11 do not apply to the situation of colonization with MSSA specifically. Thus, Z22.321 is the most appropriate choice to reflect the state of colonization with MSSA.