Importance of quality control of baciloscopy in laboratories that perform diagnosis of tuberculosisBackground: Baciloscopy is the primary tool for pulmonary tuberculosis diagnosis, being this technique the most used internationally in the search for infectious cases. Quality control is the process of the rechecking smears by a highly qualified observer. Aim: To evaluate and highlight the importance of quality control of smear microscopy in the Provincial Laboratories diagnosticians of Tuberculosis in Cuba. Methods: This study was conducted at the National Reference Laboratory and Research in Tuberculosis, Leprosy and Mycobacteria in the Institute of Tropical Medicine "Pedro Kouri", Havana, Cuba, Were evaluated 2676 smears received from January 2013 to December 2014, from Provincial Centers of Hygiene, Epidemiology and Microbiology of Cuba, including the special municipality Isla de la Juventud. Results: 2,664 (99.5%) were concordant smears, the correlation obtained for the positive smears were 96.5% and 99.8% for negative. Were identified12 reading errors: 7 (3.5%) false positive and 5 (0.2%) false negatives. Slides were classified with adequate quality of smears in 2039 (76.2%), showed difficulties in realizing the extension in 1464 (54.7%) and staining were adequate in 2343 (87.6%). The kappa index was 0.9674. Conclusion: Although there was good agreement between observations it is recommended to improve the quality of extended, maintain staff training program that performs this activity, like regular supervision by specialists, to further improve the quality of diagnosis.

This study shows low prevalence of multidrug-resistant strains in Cuba. The results reflect the progress made by the national control program, which is currently working on the elimination of tuberculosis as a public health problem in the country.

Background: The rapid diagnosis of mycobacterial infections is essential to implement the adequate antimicrobial therapy. This study evaluates the performance of the BacT/ALERT 3D system for isolates and identification of mycobacteria from clinical samples. Methods: 1011 clinical specimens from nonsterile and sterile body sites were studied from August 2010 to December 2012 at the National Reference Laboratory of Tuberculosis, IPK, Cuba. The results obtained were compared with respect to time detection of mycobacteria and contamination rates, and performance indicators of BacT/ALERT 3D were calculated. Results: The time detection of growth (TDG) for Mycobacterium tuberculosis (Mtb) and nontuberculous mycobacteria (NTM) by BacT/ALERT 3D was 16,435 and 10,956, respectively; by LJ the TDG was 33.577 for Mtb and 35.952 for NTM. By culture method used the TDG for LJ was 33,577 and 6.435 by BacT/ALERT 3D, this difference being statistically significant. The overall contamination rate (CR) for BacT/ALERT 3D was 4.6% and 7.8% for LJ. Conclusions: BacT/ALERT 3D were a suitable method for recovering mycobacteria from clinical samples. It demonstrated a shorter time to detection of mycobacteria growth; it was very useful to provide faster treatment and a better prognosis in patients AFB smear negative with HIV. The use of LJ culture and BacT/ALERT 3D System was useful to assure a total mycobacterial recovery.

No abstract