Yield of primary and repeat induced sputum testing for Pneumocystis jiroveci in human immunodeficiency virus-positive and -negative patients

Department of Pathology, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA 02215, USA.
Archives of pathology & laboratory medicine (Impact Factor: 2.84). 11/2007; 131(10):1582-4. DOI: 10.1043/1543-2165(2007)131[1582:YOPARI]2.0.CO;2
Source: PubMed


Induced sputum sampling has an approximate 70% sensitivity for detection of Pneumocystis jiroveci in human immunodeficiency virus (HIV) patients. Bronchoalveolar lavage sampling has greater than 90% sensitivity but is a far more invasive procedure. Therefore, bronchoalveolar lavage testing is often recommended as a follow-up after a negative induced sputum. In HIV-negative patients, the utility of induced sputum testing is still not well defined.
To determine whether repeat induced sputum sampling increases diagnostic yield and might thereby reduce the need for follow-up bronchoalveolar lavage sampling. To determine the utility of induced sputum sampling in HIV-negative patients.
A 2-year retrospective review of the utility of repeat induced sputa testing in patients with previous first and/or second negative induced sputa. Retrospective review of induced sputa detection in HIV-negative patients.
Repeat testing of induced sputa for Pneumocystic jirovecii did not significantly increase diagnostic yield. Furthermore, in HIV-negative patients, induced sputum testing was diagnostically insensitive.
Bronchoalveolar lavage testing should be performed initially in HIV-negative patients and after a first negative induced sputum in HIV-positive patients.

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