Unspecified blood type, Rh negative

This code indicates that a patient's blood type is known to be Rh negative, but the specific ABO blood group (e.g., A, B, AB, O) has not been documented or determined. It signifies an incomplete understanding of the patient's full blood type profile, specifically lacking the ABO component.

This code is appropriate when a patient's medical record clearly states "Rh negative" without further specification of the ABO group. It may be used in situations where only the Rh factor is relevant or available at the time of coding, such as initial screening or when a more precise blood type is not yet known.

• Only use this code when the ABO blood group is truly unspecified in the documentation.
• If the ABO group is known and documented, use the more specific Z67.xx code that includes both ABO and Rh factors.
• Avoid using this code if the documentation simply states "blood type unknown"; in such cases, a different code for "unspecified blood type" (Z67.90) would be more appropriate.