Recent advances in laboratory procedures for pathogenic mycobacteria

Endoscopic ultrasound-guided fine-needle aspiration: sampling, pitfalls, and quality management

Endoscopic ultrasound-guided fine-needle aspiration (EUS FNA) is an accurate and versatile technique in the diagnosis of gastrointestinal tract lesions as well as other organ sites. EUS FNA is performed ideally with cytopathologic adequacy evaluation, and diagnosis at the time of tissue procurement. In this article, we review the most relevant issues in the process of EUS FNA-based diagnostics. Specifically, we describe the technical aspects of specimen collection, processing, and appropriate selection of ancillary studies. We also illustrate the most commonly encountered diagnostic pitfalls, and methods for their avoidance. Lastly, we discuss quality management, which emphasizes the communication between the endoscopist and the pathologist.

Use of the INNO LiPA Rif.TB for detection of Mycobacterium tuberculosis DNA directly in clinical specimens and for simultaneous determination of rifampin susceptibility

The INNO LiPA Rif.TB (Innogenetics, Ghent, Belgium) is a reverse hybridization test developed to detect genetic markers of resistance to rifampin in Mycobacterium tuberculosis complex. In the present study, this test was used directly on 3,763 clinical specimens by adopting a nested amplification of the target. The specificity of the system (98.4%) was optimal, but sensitivity (69.5%) was unsatisfactory. However, when use of the system was limited to smear-positive specimens, the sensitivity rose to 91.7%. As expected, the ability of the system to predict rifampin resistance was not influenced by its direct use on clinical specimens and confirmed the favorable results repeatedly reported in the literature.