Routine using pattern and performance of diagnostic tests for tuberculosis on a university hospital.
BACKGROUND
Nucleic acid amplification tests to detect Mycobacterium tuberculosis in clinical specimens are used increasingly as a laboratory tool. We aimed to investigate the routine using pattern and the effects on therapeutic decision of diagnostic tests for tuberculosis in our hospital.


METHODS
In this descriptive study, we investigated retrospectively the routine using pattern and the effects on therapeutic decision of diagnostic tests for tuberculosis. Patients with discordant results were clinically evaluated retrospectively by a chest physician. Samples were tested for the presence of M. tuberculosis by a smear technique, M. tuberculosis culture growth technique (Löwenstein-Jensen and/or BACTEC-960), and IS6110 polymerase chain reaction (PCR).


RESULTS
Culture positivity was 7.2% (83 of 1159 patients). In total, 198 (62.4%) were tested with PCR, acid-fast bacilli, and culture. On the basis of culture results as a gold standard, sensitivity, specificity, positive predictive value, and negative predictive value of PCR were 46%, 89%, 23%, and 93.5%, respectively.


CONCLUSIONS
Selection of appropriate patients for further testing and exclusion of low-risk patients from microbiologic testing by experienced clinicians may help to optimize the positive predictive value of PCR.
Dundar
Devrim
D
Department of Microbiology and Clinical Microbiology, Medical Faculty, Kocaeli University, 41380 Kocaeli, Turkey.
Sayan
Murat
M
Arslan
Zeliha
Z
Tamer
Gulden Sonmez
GS
Dundar
Volkan
V
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001431:Bacteriological Techniques / Q000379:methods / Q000592:standards; D003955:Diagnostic Tests, Routine / Q000379:methods / Q000592:standards*; D005260:Female; D006785:Hospitals, University / Q000592:standards*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification; D012189:Retrospective Studies; D014376:Tuberculosis / Q000175:diagnosis* / Q000382:microbiology; D055815:Young Adult