B97.31Lentivirus as the cause of diseases classified elsewhere

B97.31 is the ICD-10-CM diagnosis code for Lentivirus as the cause of diseases classified elsewhere. It belongs to category B97 (viral agents as the cause of diseases classified elsewhere), block B95-B97 (bacterial and viral infectious agents) and chapter 1 (certain infectious and parasitic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within B97.3 (retrovirus as the cause of diseases classified elsewhere), B97.31 is specifically for Lentivirus as the cause of diseases classified elsewhere. Related codes cover unspecified retrovirus as the cause of diseases classified elsewhere (B97.30), Oncovirus as the cause of diseases classified elsewhere (B97.32), human T-cell lymphotrophic virus, type I [HTLV-I] as the cause of diseases classified elsewhere (B97.33), human T-cell lymphotrophic virus, type II [HTLV-II] as the cause of diseases classified elsewhere (B97.34), human immunodeficiency virus, type 2 [HIV 2] as the cause of diseases classified elsewhere (B97.35) and other retrovirus as the cause of diseases classified elsewhere (B97.39).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 865 (Viral Illness with MCC, relative weight 1.3485) and DRG 866 (Viral Illness without MCC, relative weight 0.8692), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 079.59 (other specified retrovirus).