Genotype and antiretroviral drug resistance of human immunodeficiency virus-1 in Saudi Arabia

To analyze antiretroviral drug resistance and determine the genotype of human immunodeficiency virus [HIV]-l in Saudi patients by sequencing an amplified region of the viral pol gene. This retrospective study analyzed data from plasma samples submitted for genotypic drug sensitivity monitoring. Samples were analyzed at the Special Infectious Agent Unit, King Fahd Medical Research Center of King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia from August 2004 to June 2009. The Viroseq2.5 kit [Celera/Abbott] was used with ABI Prism 3100 sequencer. All patients were Saudi nationals and were on antiretroviral therapy, some experiencing treatment failure. Based on protease region [PR], genotypes of 63 samples were as follows: C:22, G:21, B:9, CRF02_AG:5, D:3, A:l, F:l, and J:l. Based on reverse transcriptase region [RT], genotypes were as follows: C:23, G:24, B:9, CRF02 AG: 2, D:2, A:l, and F:l. Antiretroviral susceptibility testing results were as follows: 52% of the isolates were susceptible to all 3 major classes of antiretroviral drugs used, 41% had mutations known to confer high level resistance to one or more of the nucleoside analogue reverse transcriptase inhibitors, 16% had mutations known to confer high level resistance to non-nucleoside analogues reverse transcriptase inhibitors, 13% had mutations known to confer high level resistance to one or more of the protease inhibitors [PI]. Most isolates were susceptible to 2 or at least one class of antiretroviral, and only 3% of the isolates had resistance to several members of all 3 classes. Antiretroviral resistance is not uncommon in Saudi patients on antiretroviral therapy

New and re-emerging pathogens

This manuscript aims to highlight a few of the new or re-emerging viruses that have made "news" recently. Of these are HIV, Hantavirus, monkeypox virus, dengue virus, influenza virus l and 5 NI, Kaposi's sarcoma-associated herpes virus [KSHV], Borna disease virus, Ebola virus, other haemorrhagic fever viruses, Al-Khorma virus, hepatitis G virus, Calicivirus gastroenteritis, Enteroviral meningitis, Bovine prions and nvCJD. The advances in molecular techniques made it possible to detect new viruses. The new molecular tools for the identification of unculturable viruses are discussed

Follow up of HIV western blot indeterminate results

Indeterminate results obtained with the Western blot [WB] confirmatory test on HIV enzyme immunoassay [EIA]-positive samples, constituted 15.6% [444 / 2849] over a 2.5-year period at the referral laboratory for the Western region at the King Fahd General Hospital, Jeddah. Two hundred and fourteen WB-indeterminate samples were followed up by repeat WB testing of subsequent samples from the same patients over a 3-12 month period. One hundred and forty-two samples [66.4%] gave negative results. Sixty-five samples [30%] remained indeterminate. Only seven samples [3.3%] not initially meeting WHO criteria for positivity turned clear-cut positive, with high EIA readings on follow-up. It was discovered initally that a significant proportion of indeterminates was due to low-grade cross-contamination between samples as a result of aerosol backflow during aspiration in the washing procedure. This was eliminated by rinsing the lines between samples, separating samples with high EIA from those with low EIA, and rerunning indeterminate samples. A reduction of indeterminates from 21% to 8.5% subsequently followed. After this improvement, most of the samples that remained indeterminate had low EIA readings, and few bands of mainly anti-gag [p55, p24 or pi8] or anti-pol [p51] antibodies, while the few turning positive all had anti-gp160, in addition to anti-p24 or p55. Interestingly, over the last year and a half of the study, 1.4% of the total samples [21/1506] had repeatedly high EIA readings but were negative by WB. In addition, 16 samples [1.1%] were positive for HIV-2. A separate computer-based system for the storage of data was very helpful in ascertaining proper follow-up of indeterminate WB results

Hepatitis A and hepatitis B in the Asir region, Southwestern Saudi Arabia

This study was conducted to gather information on the prevalence of hepatitis A and hepatitis B in the Asir region of southwestern Saudi Arabia and to optimize the use of routine serological tests in the diagnosis. Three serological marker were determined concurrently by enzyme immunoassay for patients with acute hepatitis admitted to a fever hospital and to suspected hepatitis patients at two general hospitals in Saudi Arabia during 7 January 1987 until 15 May 1989. These markers were the I[g]M antibody to hepatitis A, the hepatitis B surface antigen, and the I[g]M antibody to the core antigen of hepatitis B. Of the serological patterns obtained indicated that hepatitis A afflicted 43% while hepatitis B affected 9% of the patients with acute hepatitis admitted to the fever hospital. In contrast, hepatitis A could only be diagnosed in 5.6% and hepatitis B in 2% of the patients from the other two hospitals. The incidence of hepatitis A peaked in early childhood while that of hepatitis B peaked in middle age. The identification of some patients was uncertain, particularly those with chronic hepatitis who were negative for the hepatitis B core I[g]M but positive for hepatitis B surface antigen from normal healthy carriers of this antigen, who accounted for about 6% of blood donors in the region during study period