association between human leukocyte antigens and hypertensive end-stage renal failure among Yemeni patients

Many studies have attempted to locate a connection between various genetic factors and the pathogenesis of certain diseases. A number of these have found human leukocyte antigens [HLAs] to be the most significant genetic factors affecting the susceptibility of an individual to a certain disease. The present case control study aimed to determine the connection between class I and class II HLAs and cases of hypertensive end-stage renal failure [HESRF], as contrasted with healthy controls, in Yemen. The study was carried out between March 2013 and March 2014 and included 50 HESRF patients attending the Urology and Nephrology Center at Al-Thawra University Hospital in Sana'a, Yemen, and 50 healthy controls visiting the same centre for kidney donation. Among both patients and controls, HLA class I [A, B and C] and class II [DRB1] genotypes were determined by polymerase chain reactions. There was an association [odds ratio: 4.0] with HLA-A9 [24] and HESRF, although this was not statistically significant. A significant protective function was found for the HLACW3 and DRB1-8 genes against the development of HESRF. Although HLA-B14 was present in some patients [0.06] and not in the controls, this difference was not statistically significant enough to conclude that HLA-B14 plays a role in the genetic predisposition for end-stage renal disease development. There was a high frequency of HLA-A2, B5, CW6, DRB1-3, DRB1-4 and DRB1-13 in both patients and controls. Although no HLAs were found to play a highly significant role in genetic predisposition to HESRF, certain HLA genes could be considered as protective genes against HESRF development

Clinical and laboratory manifestations of Yemeni patients with systemic lupus erythematosus

Systemic lupus erythematosus [SLE] is a chronic autoimmune disease characterised by multi-systemic involvement. This is the first study undertaken to determine the relationships between serological marker positivity and age, gender, signs and symptoms, risk factors and the treatment of SLE in Yemen. We investigated the cases of 149 patients with SLE admitted to Al-Thawra Hospital in Sana'a city between November 2009 and November 2010. Of the 149 patients, females represented 75.2% and males, 24.8%. The most frequent presenting signs and symptoms were fatigue [84.6%], fever [81.9%], arthropathy [81.2%], anaemia [64.4%], photosensitivity [54.4%], renal involvement [53%], malar rash [52.3%], and alopecia [49%]. Antinuclear antibodies [ANA] were detected in 95.3% of the patients and were associated significantly with most clinical presentations, except weight loss, hypertension and serositis. Anti-ds deoxyribonucleic acid [anti-dsDNA] was detected in 59.7% of the patients, and was associated significantly with fever and fatigue. Anti-Smith [anti-Sm] antibodies were detected in 27.5% of the patients, but were not significantly associated with all clinical presentations. Social stress was the most important risk factor for inducing SLE, with an odds ratio [OR] of 6.0, followed by common exposure to sunlight [OR = 2.2]. In this study, SLE was more prevalent among females and young adults. The clinical presentation was characterised by a high incidence of fatigue and fever, and a low incidence of oral ulcers and serositis. ANA was associated with most clinical presentations except weight loss, hypertension, and serositis. Antids-DNA antibodies were most frequently associated with fever, fatigue and hypertension. There was no significant association of the anti-Sm antibodies with any clinical presentations

Prevalence of rabies in various species in Yemen and risk factors contributing to the spread of the disease

This study aimed to describe for the first time the prevalence of the passively-reported rabies virus among different domestic and wild animals submitted to the Central Veterinary Laboratory from various areas in Yemen, and to study prevalence proportion ratios [PPR] that contributed to the spread of rabies among animals, and its transmission to humans. A brain sample was obtained from each of the 180 animals and tested for rabies virus by a direct fluorescent antibody test. Out of the total number of animals involved in attacks on humans, 63.3% were positive for rabies. Of these, dogs were the main animal involved in attacks with a percentage of 92%, of which 62.7% were positive for rabies. Of animals involved in attacks, 70.6% were males of which 60.6% were positive, and 29.4% were females of which 69.8% were positive. Males comprised 68.9% of the total human individuals attacked, of whom 62.9% were attacked by rabies-positive animals. The significant risk factors that contributed to the spread of rabies in general included the presence of poultry carcasses and other waste in the vicinity of the attacks [PPR = 9.5] with a percentage of 84.8%, followed by the time of year, in particular school vacations [PPR = 3.8] with a percentage of 78%. Rabies is endemic in Yemen with a very high rabies-positive rate for animals involved in attacks, particularly for stray male dogs. Male children were most often involved in attacks by rabies-positive animals. The presence of food waste [particularly poultry carcasses] and school vacation periods were found to correlate significantly with increased risk for human exposure to rabies

Types of bacteria associated with neonatal sepsis in Al-Thawra University Hospital, Sana'a, Yemen, and their antimicrobial profile

This study was undertaken to investigate the organisms causing sepsis in the Neonatal Unit at Al-Thawra Hospital, Sana'a, Yemen, determine their resistance to antibiotics, and recommend policy for empirical treatment. A total of 158 neonates having one or more signs of sepsis, and aged from 0 to 28 days, were enrolled in this study. A blood sample was taken from each subject, cultured, and then antibacterial susceptibility tests were performed for isolates. 90 [57%] cases yielded positive cultures. Early-onset sepsis showed higher positive culture results [61.7%] than late-onset sepsis [32%]. Significant positive culture results were found among the group with birth weight 0.9-2 Kg [78.6%]. Gram negative bacteria constituted 97.8% of the total isolates, of which Klebsiella pneumoniae was the predominant pathogen [36.7%], followed by Pseudomonas species [30.0%]. The commonest symptoms among the cases were respiratory distress [72.2%], jaundice [62.2%], cyanosis [51.1%], and lethargy [47.8%]; the mortality rate was 27.8%. All Gram negative bacterial isolates were sensitive to imipenem and some isolates were sensitive to fourth-generation cephalosporins, but most isolates were highly resistant to the majority of other antibiotics tested. Gram negative organisms were the most frequent causative agents of bacterial sepsis, which is a significant cause of mortality and morbidity in the newborn, and particularly in those of very low birth weight. It can also be concluded that imipenem and fourth-generation cephalosporins can be used for empirical treatment of bacterial sepsis

Hepatitis B vaccine coverage and the immune response in children under ten years old in Sana'a, Yemen

The study was undertaken, first, to determine the coverage rate of hepatitis B [HB] vaccine and second to evaluate the immune response to HB vaccine among children under 10 years old by measuring the level of circulating anti-HB surface antigen [anti-HBs] antibodies after immunization with three doses. First, 840 children were randomly selected from 4 randomly selected sites in Sana'a city to study the coverage rate of the vaccine; of these, 504 children vaccinated against HBV prior to the study, were tested [56% males and 44% females]. Sera were tested for anti-HBs antibodies by ELISA quantitative technique. Each individual's data was collected in a pre-designed questionnaire including: vaccination date, sex, and age at the time of the study. The coverage rate of HBV vaccine was only 69.9%, being slightly higher among male children [72.1%] than female children [66.8%]. A total of 276 [54.8%] of the 504 children responded to the vaccine with anti-HBs antibody level >/- 10 mIU/ml, while 228 [45.2%] of the 504 children had non-protective anti-HBs antibodies levels [<10IU/ml]. Children of ages 3-5 years had the highest protective rate [63.6%], and the lowest protective rate was in the 9-10 years age group. This study revealed a low coverage rate of HBV vaccine and a low protective rate against HBV infection. A considerable proportion of vaccinated children should be considered for either revaccination or booster doses. There is also the need to complete HBV vaccine coverage among the child population in San'a, Yemen

Evaluation of the immune response to Hepatitis B vaccine in different age groups of the population of Sana'a - Yemen

The study was made to evaluate the immune response to HBV among individuals with different ages and sexes by measuring the level of circulating anti-HBs antibodies over an interval of 1 to 5 years after immunization with the three doses of hepatitis B vaccine. A total of 300 individuals vaccinated against HBV prior to the study were included, of whom males represent 47.7% and females 52.3% with a mean age of 26.67 years. Sera were tested for HBsAg and anti-HBc by qualitative ELISA and anti-HBs by ELISA quantitative technique.The individual's data were collected in a pie-designed questionnaire including: vaccination date, number of doses of vaccine, sex, occupation and age at the time of the present study. Two hundred and sixteen [81.2%] of 266 individuals [lacking both HBsAg and anti-HBc] responded to the vaccine with anti-HBs antibody level >/= mlu/ml. Thirty-four [11.3] of 300 individuals wre reactive to anti-HBc, indicating an immune response due to previous infection rather than vaccination. Seven [2.3%] of all vaccinated individuals were reactive to HBsAg, indicating infection, Individuals having ages < 15 years had the highest immune response [89.8%] with antibody level >/= 10mlu/ml. There was no difference in response at ages from 16-35 [82.8%], while the lowest response was obtained at ages >36 years [66.7%]. The present study included two vaccination schedules, the first one at 0,1,2 months, showing an immune response of 62.2%, while the second schedule at 0,1,6 months showed a greater immune response of 83.1%. Individuals immunized with a yeast-derived vaccine had higher anti-HB5 levels [81.9%], than those immunized with a plasma-derived vaccine [79.8%].The year intervals [1-5 years] after primary immunization showed no difference in the immune response. This study revealed a high response rate to the vaccine. However, a considerable proportion of vaccinated individuals remain to be reconsidered for either revaccination or booster doses due to nonexistent, inadequate, or low response. The schedule of 0, 1, and 6 months was more efficient in inducing antibodies towards the vaccine than the 0, 1, 2 months schedule

therapeutic efficacy of sulfadoxine/pyrimethamine against plasmodium faldparum in Yemen

The aim of this study was to determine the sensitivities of Plasmodium falciparum clinical isolates to sulfadoxine/pyrimethamine [SP] using in vivo and in vitro methods. In vivo and Mark III in-vitro test techniques according to World Health Organization protocols of antimalarial drug tests were used to determine the SP susceptibility of the P. falciparum isolates from 100 malaria patients of both sexes between the ages of 3.5 and 45 years and living in Tihamah, Yemen. The study was conducted between 19 March and 12 May 2005. In vivo: no therapeutic failure occurred; the clinical outcome matched the parasitological response and all patients were parasite free by day 3 and remained so on days 7, 14 and 28. In vitro: all the P. falciparum isolates developed to schizonts in zero-drug-concentration wells, but were inhibited in 40 nmol/l of SP; the mean effective concentration [EC99] was 67.17 nmol/l. Our findings showed that the SP combination is still effective for the treatment of uncomplicated P. falciparum malaria in Yemen. It is recommended that further studies be carried out to address the importance of dihydropteroate synthetase/dihydrofolate reductase mutations as predictive markers of sulfadoxine/pyrimethamine resistance in Yemen

prevalence of streptococcus pneumoniae carriage among healthy children in Yemen

Elevated nasopharyngeal carriage rates of Streptococcus pneumoniae is an important epidemiological factor in the incidence of clinical infections caused by this microorganism. This study was aimed to determine the carriage rate of S pneumoniae among healthy children in Sana'a, Yemen, the antibiotic susceptibility of the isolates, risk factors predisposing to the colonization by this microorganism, and serotype the isolates of S pneumoniae. From January 2006 to June 2006, 602 nasophanygeal swabs from children were collected. A standard questionnaire for collecting information about risk factors for predisposing S pneumoniae carriage was filled for each child. Carriage was defined by positive cultures for S pneumoniae. The isolates identified as S pneumoniaee based on colony morphology, Gram staining, type of haemolysis on blood agar, optchin sensitivity, bile solubility and serotyping was done by using commercial antisera. Sensitivity to antibiotic for S. pneumoniaee was determined using standard Kirby Bauer technique. During the six months of the study, 602 children met the study criteria for collection nasopharyngeal swabs and were free from current upper respiratory tract infections. They were 365 [60.6%] males and 237 [39.4%] females. The crude prevalence rate of S pneumoniae was 5.6%, the male specific prevalence rate was 6% and the female specific prevalence rate was 5.1%. There were significant effect between S pneumoniae carriage and nose bleeding [OR=2.5, CI=1-6, X2=4.7, pv=0.02] and with tonsillectomy [OR=2.3, CI=0.8-6.8, X2=2.9 pv=0.08], and hospital visit [OR=4.1, CI=1.9-8.6, X2=17.4, and pv> 0.0001.]. 30 of the 32 isolates S pneumoniae were distributed among six different serotypes. 9 [30%] belonged to serotype 5. Serotype 19 count 7 [23.3%], and serotypes 1, 15 and 22 count 6 [20%] and 4 [13%], 2 [6.6%] respectively. S pneumoniae isolated in the present study was tested against 11 different antimicrobial agents, 93.3% of the isolates were resistant to penicillin, 93.3% to gentamycin. 33.3% to chloramphenicol, and 20% to co-trimoxazol and 0% to erythromycin. Multi-resistant S pneumoniae was occurring; the most predominant drug resistance pattern was of three antibiotics [73.3%]. We conclude that, the rate of carriages and frequency of different types of S pneumoniae strains are similar to that reported in Middle East countries. However multi and single drugs resistance were higher than those reported in developed and developing countries

Seroprevalence of Helicobacter pylori among children in Sana'a, Yemen

Helicobacter pylon infection is primarily acquired in early childhood. Its transmission routes are debated. The aims of this study were to determine the seroprevalence of anti-H. pylori immunoglobulin G [IgG] in Yemeni children under 10 years of age, the potential risk factors for contracting H. pylori infection and co-infection of H. pylori with intestinal parasites. Enzyme-labeled immunosorbent assay was used to determine the H. pylori prevalence rate among 572 healthy volunteers aged less than 10 years. Formalin ether concentration methods were used to test the prevalence of intestinal parasites [intestinal roundworms and tapeworms]. In addition, we interviewed participants regarding potential risk factors for contracting H. pylori infection. The seroprevalence of H. pylori antibodies was 90%. The prevalence according to age varied from 0% in children under 2 years to 12.5% in age group 9-10 years. There was a correlation between the amounts of positive antibodies and increasing age. The prevalence rate of H. pylori antibodies was also significantly associated with the practice of drinking water from reused plastic jerry cans, with poor mouth hygiene and with co-infection by intestinal parasites. The prevalence of H. pylori antibodies in Yemen among children under 10 years of age is higher than that reported from other regions for the same age groups. Yemen shares some but not all potential risk factors for H. pylori infection with countries in which similar socioeconomic conditions are found. A possible way of eliminating H. pylori from the population would be via public health measures, i.e. preventing the reuse of plastic jerry cans, and improving sanitation and the standard of living

Increasing single and multi-antibiotic resistance in Shigella epecies isolated from shigellosis patients in Sana'a, Yemen

The epidemiology and antibiotic susceptibility of Shigella species changes over time. Updated susceptibility knowledge is necessary for appropriate empirical antibiotic treatment. Thus, this research aimed to study these changes in 2 time periods with an interval of 10 years. Two hundreds and three Shigella strains, isolated from stool samples of diarrheic patients at the Central Health Laboratory in Sana'a, Yemen in 2 time periods [1993 and 2003] with a 10-year interval, were examined for serotyping and drug resistance pattern. Resistance patterns of the strains to 12 commonly used antimicrobial agents and minimum inhibitory concentrations of the antibiotics were tested. Shigella flexneri [60%] was found to be the most common isolate of the total Shigella species, followed by Shigella dysenteriae [28.6%] and Shigella boydii [11.3%]. In Shigella flexneri strains, Shigella flexneri 3 [30.5%] was the most prevalent serotype, followed by Shigella flexneri 6 [17.2%], and Shigella flexneri 1 [12.3%]. All strains were found equally susceptible to cefotaxime, ceftriaxone, ciprofloxacin, and gentamicin, but more than 80% of the strains of 2003 were resistant to tetracycline, co-trimoxazole, and 52% of the same strains were resistant to ampicillin. Resistance to chloramphenicol was found in 61%, cefuroxime in 56.2%, and cephradine, 52% of the strains. Overall, Shigella species showed statistically significant increase in resistance against tetracycline, cephradine, trimethoprim/sulfamethoxazole, nalidixic acid, and aztreonam [p<0.05] over the 10 years period. This indicates decreased efficacy of co-trimoxazole and nalidixic acid for the empirical treatment of shigellosis in Sana'a, Yemen. Almost 55.2% of the strains were resistant to 4 drugs. This is one of the first studies reporting epidemiological pattern of Shigella species in Sana'a, Yemen with regard to serotypes and antibiotic resistance patterns. Based on these antibiotic resistance pattern findings, it is suggested that the commonly in use antibiotics including ampicillin, trimethoprim/sulfamethoxazole, tetracycline, and chloramphenicol should not be used for empirical treatment of shigellosis in Yemen

Seroprevalence of Helicobacter pylori among children in Sana'a Yemen

Helicobacter pylori infection is primarily acquired in early childhood. Its transmission routes are debated. The aims of this study were to determine the seroprevalence of anti-H. pylori immunoglobulin G [IgG] in Yemeni children under 10 years of age, the potential risk factors for contracting H. pylori infection and co-infection of H. pylori with intestinal parasites. Enzyme-labeled immunosorbent assay was used to determine the H. pylori prevalence rate among 572 healthy volunteers aged less than 10 years. Formalin ether concentration methods were used to test the prevalence of intestinal parasites [intestinal roundworms and tapeworms]. In addition, we interviewed participants regarding potential risk factors for contracting H. pylori infection. The seroprevalence of H. pylori antibodies was 9%. The prevalence according to age varied from 0% in children under 2 years to 12.5% in age group 9-10 years. There was a correlation between the amounts of positive antibodies and increasing age. The prevalence rate of H. pylori antibodies was also significantly associated with the practice of drinking water from reused plastic jerry cans, with poor mouth hygiene and with co-infection by intestinal parasites. The prevalence of H. pylori antibodies in Yemen among children under 10 years of age is higher than that reported from other regions for the same age groups. Yemen shares some but not all potential risk factors for H. pylori infection with countries in which similar socioeconomic conditions are found. A possible way of eliminating H. pylori from the population would be via public health measures, i.e. preventing the reuse of plastic jerry cans, and improving sanitation and the standard of living

prevalence of brucella antibodies in Yemen

To determine the prevalence of seropositivity to brucella among individuals in five selected areas in Yemen. Study design: A cross-sectional survey. The study was conducted in five major population areas in the Yemen. The study population consisted of all those donating to blood banks. A tube standard agglutination test was used to indicate positive serology. A total of 1405 samples were selected. Five persons had a titre of >/= 1:160 which was considered positive for brucella antibody. The rate of serologically positive sera ranged from 0 to 0.8%. This data shows that sero-prevalence of brucella in Yemen is lower than other nearby countries in the Arabian Peninsula and demonstrates the importance of regional variations of the disease in these endemic areas