Table 1.

Participant characteristics

	Patients with no demonstrated TBa (n=408)	Patients with active TBb (n=27)	p-valuec
Age in years, mean ± SD	34.1 ± 10.7	34.7 ± 10.3	0.78
Women	158 (39%)	4 (15%)	0.01
Previous TBd	60 (15%)	2 (7%)	0.29
Previous isoniazid preventive therapye	58 (14%)	4 (15%)	0.94
Recent TB contactd	125 (31%)	8 (30%)	0.91
Positive tuberculin skin test (≥5 mm)f	116 (32%)	13 (59%)	0.008
CD4 cells/μL, mean ± SDg	246 ± 190	164 ± 96	0.06
Two or more symptoms (cough, fever, weight loss, night sweats) for ≥ 14 daysh,i	60 (15%)	8 (30%)	0.08

Data are presented as number (percentage), unless otherwise noted. Nineteen patients who provided less than two sputum samples are excluded. Five patients were hospitalized at the time of enrollment; the remainder were ambulatory.

^aDefined as having only negative microbiologic tests.

^bDefined as having at least one positive microbiologic test.

^cChi-square for categorical variables, t-test for continuous variables.

^dSelf-reported, one non-response.

^eSelf-reported, two non-responses.

^f368 TB-negative patients and 22 TB-positive patients returned for reading of a tuberculin skin test placed at the time of enrollment.

^g375 TB-negative patients and 20 TB-positive patients had a documented CD4 count within six months of study enrollment.

^hSelf-reported by 404 TB-negative patients and 27 TB-positive patients.

ⁱThe positive predictive value (PPV) of having two or more of these symptoms for ≥14 days was 11.8%, the negative predictive value (NPV) was 94.8%, and the positive likelihood ratio (LR) was 1.7; for those with CD4<200, PPV was 10.0% (p=0.75), while for those with CD4≥200, PPV was 4.5% (p=0.62). The PPV of having any of these symptoms for any period of time was 8.0%, the NPV was 97.7%, and the positive LR was 3.5. Three patients with active TB were asymptomatic. Because of the low PPVs, and because symptoms do not figure in Peruvian screening guidelines, no further evaluations of symptoms as a screening tool were undertaken.