Rapid diagnosis of Mycobacterium tuberculosis by multiplex polymerase chain reaction from clinical specimens.

An essential element in the control of tuberculosis is the rapid, sensitive and specific identification of the causative agent. Until now, screening and diagnosis are largely based on clinical signs, radiological examination, tuberculin tests, sputum examination under the microscope, or culture for mycobacteria. Tuberculin tests lack specificity and only give an indication of previous exposure to mycobacteria. Direct microscopic examination of sputum is neither specific nor sensitive enough, and mycobacterial isolation is time-consuming. As an alternative to these classical methods, new nucleic acid-based technologies show promise as a more rapid, sensitive, and specific means of identification of mycobacteria. Two commercial standardized nucleic acid-based amplification techniques have been reported to yield reliable results within 5 to 7 hrs. Roche Amplicor MTB (Roche Diagnostic System, Somerville, N.J.) and Gen-Probe AMTB (Gen-Probe Inc., San Diego, Calif.). The amplified target is part of the 16S rRNA gene which is common to all the mycobacteria. An attempt has been made to describe the use of the target DNA, SenX3-RegX3, in a multiplex PCR to detect and differentiate M. tuberculosis from other mycobacteria directly from clinical specimens.

Epidemiology of HIV and AIDS in Bahrain.

Between 1986 and 1996, 378 HIV cases were identified in Bahrain, of whom 51% were foreign nationals. Intravenous drug abuse was a major risk factor (38.8%) among Bahraini nationals, while transmission through sexual contact was more common (45.7%) among foreigners. Other well known risk factors were also represented in the two communities. The male to female ratio for the two communities were very different with 10:1 for nationals compared to 1:1.4 for foreigners. Among the AIDS defining manifestations, Pneumocystis carinii pneumonia was the commonest (50%), followed by tuberculosis (21%), oro-esophageal candidiasis, cryptosporidiosis and toxoplasmosis. Transmission through sex and maternal-foetus route could emerge as significant contributors in the spread of AIDS in Bahrain unless appropriate preventive steps are taken.

HIV antibodies among intravenous drug users in Bahrain.

A 12-month study was conducted to identify risk factors for human immunodeficiency virus (HIV) infections among intravenous drug users (IDU) attending drug rehabilitation clinic of the Psychiatric Hospital, Manama, Bahrain. Patients provided demographic and behavioural information based on a questionnaire. Two hundred and forty male IDUs participated in the study on voluntary basis. The seroprevalence of HIV was 21.1 per cent. The presence of HIV antibody was associated with educational status, frequency of injecting drugs and needle sharing.