This system is based on the standard cytological diagnosis on ThinPrep Pap test smears and the expression of various biomarkers.
Conventional Papanicolaou smear tests were read twice: in addition to routine reading in normal conditions ("clinical reading"), a reading blind to the context and clinical history was obtained for Papanicolaou test smears separately and independently by two different pathologists.
The reference laboratory tests (smear and culture) were performed by fully trained hospital and laboratory personnel (routine TB diagnostic lab).
However, standard microbiologic tests (smear microscopy, nucleic acid amplification tests, and mycobacterial culture) also have well known limitations, particularly in patients co-infected with HIV [ 3, 4].
The electronic laboratory information system, called e-Chasqui, supports the decentralized entry and viewing of bacteriological tests (smear microscopy, cultures, species identification, and DSTs).
In addition, the AMTD and Amplicor tests are licensed for testing smear-positive specimens, while the FDA recently approved a 2nd-generation AMTD (E-AMTD) test for smear-negative specimens [11].
His sputum tested smear-positive for acid-fast bacilli.
The sensitivity when testing smear-positive samples (pooled estimate 0.95, 95% CI 0.91 – 1.00, range 0.92 – 1.00) far exceeded that observed when testing smear-negative samples (pooled estimate 0.69, 95% CI 0.60 – 0.80, range 0.38 – 0.92).
Xpert reliably detected the vast majority of non-respiratory samples testing smear-positive, culture-positive for M. tuberculosis but approximately only two-thirds of smear-negative samples.
