The etiology of nonspecific interstitial pneumonitis in acquired immunodeficiency syndrome

SummaryInterstitial pneumonitis without evidence of Pneumocystis jiroveci infection has been described in the patients infected with immunodeficiency virus (HIV). Nonspecific interstitial pneumonitis (NSIP) is the most commonly observed pathologic diagnosis.The etiology of NSIP in HIV infected patients is unknown. We retrospectively studied 6 cases of NSIP that were diagnosed with transbronchial biopsies. The etiologic causes of NSIP were evaluated retrospectively by reviewing the inpatient and outpatient charts. The medical records from other institutions were also reviewed when available. We concluded that cocaine abuse, disseminated Mycobacterium avium complex infection, cytomegalovirus (CMV) pneumonitis, and immune reconstitution syndrome were the potential causes of NSIP in our patients with HIV infection.