House dust mite allergens in Saudi Arabia: Regional variations and immune response.

In order to assess the causative extrinsic allergic factor(s) in school-age children diagnosed as having bronchial asthma and allergic rhinitis, and to qualitatively and quantitatively evaluate the presence of house dust mites (HDMs) in the homes of these children in Saudi Arabia, a study analyzing mite contents in 165 samples collected from patientsâ indoor environment was conducted. The dust samples were collected from four regions of Saudi Arabia, showing variation in their geography and climate. Immunochemical assays were performed using ALK reagents by ELISA technique. A total of 462 children were also tested using skin prick test (SPT) method for IgE-mediated reactions to HDMs. The samples from the Central dry region revealed a very low amount of the potent house dust mites (Dermatophagoides pteronyssinus and D. farinae, the two dominant species in various parts of the world). The samples from the Southern mountainous region contained a very high concentration of Der p I (84,000 ng/g of dust), while the Western coastal region showed a high concentration of Der f I (up to 22,000 ng/g). The mid-Western agricultural region did not exhibit any significant level of either Der p I or Der f I. The maximum level of D. pteronyssinus detected in the Central dry region was 106 ng/g of dust. The data exhibit both qualitative and quantitative variations of HDMs in the three regions and may be attributed to variation in geography and climate, particularly humidity of the regions, which vary significantly. Riyadh in the Central region is considered to have low humidity (<40%), while humidity in the Western coastal region, Jeddah, and the Southern region of Abha is comparatively higher, which helps house dust mites thrive. SPT results in these regions with house dust mite allergens (in addition to other common inhalant allergens) also revealed a considerable number of IgE-mediated reactions, consistent with the frequency of house dust mites in the region. Though more data are being accumulated on the subject to conduct a statistical comparison and more skin tests are underway in the Southern region, the study suggests the presence of at least two HDMs as well as qualitative diversity and quantitative variation of house dust mites in Saudi Arabia. The study also indicates, with a considerable number of IgE-mediated reactions, the possible influence of mites in the allergic manifestations of many patients, which is not only common, but increasing in parts of the country.

The role of bronchodilators in the management of bronchiolitis: a clinical trial.

A randomized clinical trial was conducted on young children with bronchiolitis admitted to hospital with moderate illness to determine the efficacy of the bronchodilators Salbutamol and ipratropium bromide, either as a single drug or in combination, given as a nebulized solution, compared with a normal saline placebo. Eighty-nine patients, aged from 23 days to 11 months, were randomized into four groups, depending on administered drug or placebo, as follows: group 1--Salbutamol (n = 20); group 2--ipratropium bromide (n = 23); group 3--combined Salbutamol and Ipratropium bromide (n = 24); group 4--normal saline (n = 22). The groups were identical with respect to age, sex, family history of atopy, respiratory syncytial virus (RSV) positivity and enrollment score. They were scored using the clinical parameters of wheezing, retractions and respiratory rate at enrollment, at 30 and 60 minutes after the first nebulization, and after 60 minutes following completion of subsequent nebulization at 6, 12, 24 and 36 hours. We did not find any significant difference in the rate of improvement and the final score (p = 0.49) in the four groups. The same finding was also noted in children aged more than 3 months (p = 0.35) and in those positive for RSV infection (p = 0.18). The lengths of hospitalization in the four groups were also similar (p = 0.79). It is concluded that there is no role for the nebulized bronchodilators Salbutamol and Ipratropium bromide, either as a single agent or in combination, compared with normal saline placebo in treating young children in hospital with bronchiolitis.

Cladosporium as an airborne allergen in Saudi Arabia.

Airborne mold monitoring in three cities in Saudi Arabia has documented the presence of Cladosporium in high concentrations. The spore counts reached threshold levels for sensitization at Jeddah and Al-Khobar with prominent seasonal variations. The concentration in Riyadh (central region) showed levels with minor fluctuationgs and a minor peak towards the month of Novermber. Indoor monitoring also revealed the presence of Cladosporium. Ten species of Cladosporium were idenified with C. sphaerospermum, C. herbarum, C. cladosporoides and C. macrocarpum being most prevalent. The species are relevant in relation to extracts for diagnosis. Skin testing of asthmatic children in Riyadh and Makkah revealed reactivities to Cladosporium extract of 5.8% and 31.3%, respectively. This indicates that Cladosporium may be an important allergen in the region that necessitates further biochemical and immunochemical studies to confirm the allergic impact of the species of Cladosporium prevalent in the region.

The growth pattern of Saudi Arabian pre-school children in Riyadh compared to NCHS/CDC reference population.

This study compares the growth patterns of Saudi Arabian pre-school children aged 0-5 years to a reference population of American children documented by the National Center for Health Statistics/Centers for Disease Control (NCHS/CDC). The anthropometric data of weight, height and age were collected in a cross-sectional study of Saudi Arabian children in Riyadh, the capital of Saudi Arabia. The sample selection was accomplished by a 3-stage stratified random procedure, basing the stratification on location and a socio-economic index. A total of 3,795 children comprising 55.2% males and 44.8% females had complete basic anthropometric measurements among other variables. Analyses were effected by using the WorHealth Organization/Centers for Disease Control (WHO/CDC) standard software programme for calculating nutritional indicators. A combination of height for age (as an indicator of stunting) and weight for height (as an indicator of wasting) showed that a sizeable proportion (78.1%) have normal or slightly above normal nutritional status. A small proportion of the children (1.4%) were below -2.0 SD scores of the reference population for weight for height and for age. Overall, Saudi Arabian children are slightly shorter and thinner than their American counterparts. An important finding in weight for height was that nearly 20% of the children were below -2 SD scores of the reference population median. However, due to the very high per capita income, and the fact that food and other essential items are subsidised by the government, the deficits from this reference population may be attributed to inadequate health education nutrition programmes, genetic and other social factors including reproductive behaviour, rather than malnutrition.

The standard physical growth chart for Saudi Arabian preschool children.

This study presents growth charts of preschool based on cross-sectional data of the population in Riyadh, Saudi Arabia. Charts on weights and heights per age were designed separately for boys and girls. Boys consistently weighed more than girls for this age group at every age. Also, the boys were taller than the girls after the age of one year. Since the growth deficits in children from Saudi Arabia compared with internationally recommended reference populations may be attributed to genetic and environmental factors, the charts presented will suffice as a standard in monitoring the growth of Saudi children in particular and those in the Gulf region in general.

Current trends in infant feeding in Saudi society.

PIP: In 1988, health workers interviewed 4796 randomly selected mothers in Riyadh, Saudi Arabia about current infant feeding practices. The percentage of male and female infants in the study was about 50% each. The ages of the mothers varied from 20-36 years old with the distribution being 20.5% 20 years old, 56.6% 20-30 years old, 11.5% 31- 35 years old, and 7.5% = or 36 years old. Maternal age had no effect on feeding practices. 27.3% of the mothers began bottle feeding their infants at 1 month. Further, they introduced solid foods on average at 3.45 months. Most mothers anticipated on breast feeding their babies for only 4 months. 70% of the mothers had at least an elementary education while the remainder either attended intermediary school or a higher school. Approximately 30% of the mothers with elementary education exclusively breast fed their babies, while almost 70% of the mothers with higher education supplemented their breast milk with formula. The results demonstrated a negative correlation between the amount of the mother's education and breast feeding. On the other hand, 5 years earlier in a 1983 hospital based study also done in Riyadh results showed that the higher the level of education the more likely the mother was to breast feed. In this same study, researchers learned that even though 64% of the mothers visited a prenatal clinic, only 10.4% received any advice on infant feeding. Health providers should always advise pregnant women about infant feeding and specifically promote breast feeding. Additionally, pediatricians should promote breast feeding. Additionally, pediatricians should promote the benefits of breast feeding during postnatal visits. Another means of reversing this downward trend is to include the benefits of breast feeding in the curriculum of intermediate and secondary level schools.^ieng