ABSTRACT
We evaluated the COBAS AMPLICOR polymerase chain reaction [PCR] based test for the detection of Mycobacterium tuberculosis complex in 866 respiratory and non-respiratory samples. Acid-fast staining and culture on Lowenstein-Jensen medium were also performed on all samples. Of the 866 samples tested, 87 [10.0%] were PCR-positive compared to 94 [10.9%] culture positive. There were no false positive results but 7 PCR-negative, culture-positive samples were, considered false negatives after reviewing medical records of patients. A PCR inhibitory rate of 2.0% [17/866] was observed in respiratory samples only. Sensitivity, specificity, and positive and negative predictive values for this test were 92.5%, 100%, 100% and 99.1% respectively. This test is a valuable diagnostic tool for today's mycobacteriology laboratory
Subject(s)
Humans , Biopsy , Bronchoalveolar Lavage Fluid/microbiology , Cell Culture Techniques/methods , Cerebrospinal Fluid/microbiology , Coloring Agents , False Positive Reactions , Sensitivity and Specificity , Tuberculosis/diagnosisABSTRACT
All published material on the prevalence of drug-resistant tuberculosis within Saudi Arabia over the period 1979-98 was reviewed. The prevalence of single-drug-resistant tuberculosis ranged from 3.4% to 41% for isoniazid, 0% to 23.4% for rifampicin, 0.7% to 22.7% for streptomycin and 0% to 6.9% for ethambutol. The prevalence of multidrug-resistant tuberculosis [defined by WHO as resist1qance to two or more first-line antituberculosis drugs] ranged from 1.5% to 44% in different regions. No strong conclusions could be drawn owing to variations in the populations studied, geographical origins, site of Mycobacterium tuberculosis isolation [pulmonary or extrapulmonary] and drug sensitivity testing. However, the need to develop a standardized national policy for surveillance of drug-resistant tuberculosis in Saudi Arabia is clear
Subject(s)
Humans , Antitubercular Agents , Drug Resistance, Multiple, Bacterial , Molecular Epidemiology , Microbial Sensitivity Tests , Population Surveillance , Prevalence , Research Design/standards , Residence Characteristics/statistics & numerical dataABSTRACT
Although Saudi medical laboratories have developed enormously over the past 25 years, the absence of a national body for medical laboratory accreditation has meant the number of accredited laboratories [seven] remains low. Of these, five are accredited by the College of American Pathologists' Laboratory Accreditation Program [LAP]-the 'gold standard' of laboratory accreditation. It requires successful performance in the College of American Pathologists' proficiency testing programme as well as passing on-site inspections carried out by practising laboratory technicians, after which the laboratory is accredited for a 2-year period. This article gives an insight into the current situation of laboratory accreditation in Saudi Arabia and an updated overview of the process involved in obtaining laboratory accreditation from the College of American Pathologists