Other combined immunodeficiencies

This code represents a group of rare genetic disorders characterized by significant defects in both cellular (T-cell) and humoral (B-cell) immunity, leading to severe and recurrent infections. These conditions are distinct from severe combined immunodeficiency (SCID) but still result in a compromised immune system. The specific underlying genetic defect is not otherwise specified or falls outside of other classified combined immunodeficiencies.

Use this code for patients diagnosed with a combined immunodeficiency that does not fit the criteria for SCID or other more specific D81 subcategories. Documentation should clearly indicate a primary immunodeficiency affecting both T and B cell function, without a more precise diagnosis available. This code is appropriate when the physician's diagnosis explicitly states "other combined immunodeficiency" or similar terminology.

• Ensure documentation specifies a combined immunodeficiency that is not SCID (D81.0-D81.2) or another specific type (e.g., D81.6, D81.7).
• Avoid using this code if a more specific combined immunodeficiency diagnosis is documented; always code to the highest level of specificity.
• Review the patient's medical history for recurrent severe infections, opportunistic infections, or failure to thrive, which often accompany these conditions.