title: Factors affecting the yield of acid-fast sputum smears in patients with HIV and tuberculosis.
abstract: OBJECTIVE
  To evaluate the sensitivity of acid-fast sputum smears in the diagnosis of pulmonary Mycobacterium tuberculosis (MTB).
  
  
  METHODS
  Retrospective chart and radiographic film review.
  
  
  METHODS
  Department of Veterans Affairs Medical Center in New York City.
  
  
  METHODS
  All patients with positive sputum cultures for MTB during 1989 to 1991, including 100 with HIV, and 76 without HIV infection.
  
  
  METHODS
  The likelihood of a positive acid-fast sputum smear, related to chest radiograph findings, CD4 cell counts, drug sensitivity, and the presence of disseminated disease.
  
  
  RESULTS
  Overall, 60 percent of patients with HIV had positive acid-fast smears, compared with 57 percent of non-HIV-infected patients. A relative absence of cavitary infiltrates did not substantially reduce the frequency of acid-fast smears in patients with and without HIV. Patients with HIV and CD4 count < 50, 50 to 200, and > 200 had positive acid-fast smear rates of 58 percent, 60 percent, and 56 percent, respectively; HIV-infected patients with drug-resistant organisms had 65 percent positive smears. Smear positivity was 96 percent in patients with HIV infection and disseminated MTB, CONCLUSIONS: Positive acid-fast sputum smears in culture-proven MTB occur with similar frequency in patients with and without HIV. The absence of cavitary disease did not significantly reduce the frequency of positive acid-fast smears. For patients with HIV, the likelihood of a positive smear was also independent of CD4 cell counts and drug resistance. Patients with HIV and disseminated MTB had positive sputum smears in nearly all cases.
authors.affiliation: Department of Medicine, New York Department of Veterans Affairs Medical Center, NY.
authors.forename: R L
authors.initials: RL
authors.lastname: Smith
authors.forename: K
authors.initials: K
authors.lastname: Yew
authors.forename: K A
authors.initials: KA
authors.lastname: Berkowitz
authors.forename: C P
authors.initials: CP
authors.lastname: Aranda
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000097:blood / Q000453:epidemiology / Q000382:microbiology*; D000328:Adult; D000368:Aged; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology; D016009:Chi-Square Distribution; D004352:Drug Resistance, Microbial; D015497:HIV-1; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000302:isolation & purification*; D009519:New York City / Q000453:epidemiology; D013902:Radiography, Thoracic; D012189:Retrospective Studies; D013183:Sputum / Q000382:microbiology*; D013194:Staining and Labeling / Q000379:methods; D014397:Tuberculosis, Pulmonary / Q000097:blood / Q000453:epidemiology / Q000382:microbiology*