IgG and IgM antibodies to human parvovirus B19 in the serum of patients with a clinical diagnosis of infection with the virus and in the general population of Saudi Arabia.

A total of 56 samples of serum from 32 patients with a clinical diagnosis of human parvovirus B19 infection were tested for specific immunoglobulin G (IgG) and M (IgM) antibodies by means of the recently available indirect enzyme-linked immunosorbent assay (ELISA) (Parvoscan-B19, Ferring Diagnostica, Sweden). The assay was also used in order to determine the age-specific prevalence of antibodies to the virus in the general population of Saudi Arabia. Specific IgM antibodies were detected in 94% specimens collected 1 week after the onset of illness and could be detected for up to 2 months. On the other hand, specific IgG antibodies were detected in 85% patients from whom acute- and convalescent-phase serum samples were collected. Saudis begin to be exposed to human parvovirus B19 early in life and prevalence of exposure increases with age in both sexes (overall prevalence 19.0%). The availability of a commercial ELISA makes it possible to diagnose infection with the virus routinely and will help in establishing the extent of exposure to it in various communities.

Acute paralytic poliomyelitis presenting as Guillain-Barré syndrome.

The initial clinical picture and CSF changes in four children with acute ascending paralysis simulated Guillain-Barré syndrome. However, diagnosis of poliomyelitis was confirmed on the basis of isolation of wild poliovirus type I and high neutralising antibody to it. The four children had received primary vaccination with live attenuated oral poliomyelitis vaccine. It is postulated that the clinical course of paralytic poliomyelitis may be altered in children who have previously been vaccinated with live oral vaccine.

Bronchial asthma and wheeze in a desert country.

A cross-sectional, population-based study was conducted among school children (3300), aged 7-12 years, in the Kingdom of Saudi Arabia, during the period January, 1988-February, 1990. The aim of the study was to investigate the association between asthma, allergic rhinitis, wheeze and eczema among Saudi school children. The relationship between pet-ownership and respiratory allergy was also studied. Detailed information was collected about wheeze and asthma in 3041 children and history of asthma and allergic rhinitis in their parents. The population sample had a high prevalence rate of diagnosed asthma (6.8%), history of wheeze (10.5%), allergic rhinitis (17.9%), and eczema (10.8%). Allergic rhinitis was the most frequently seen respiratory illness when compared to other respiratory symptoms. The prevalence rate of asthma, allergic rhinitis and eczema among parents reflected the same pattern as that seen in the children. Prevalence rate for asthma in children with pets is twice that of children without pets (OR: 2.4; 95%, Cl: 1.8-3.1). The odds of having chronic cough (OR: 3.9; 95% Cl: 2.8-5.2), chronic wheeze (OR: 4.2; 95%, 3.3-5.4), allergic rhinitis (OR: 8.0; 95% Cl: 6.3-10.3) and eczema (OR: 2.8: 95 Cl: 2.1-3.7) was higher in children with pets than in children without pets. The present study revealed that pet-ownership was associated with increased respiratory symptoms.

IgE-mediated skin reaction among asthmatic children in Riyadh.

Fifty-five asthmatic children aged 6-13 years attending a pediatric allergy clinic were skin tested with a panel of 35 inhalant commercial allergens. The allergen extracts were grouped into pollen including trees, grasses and weeds, fungal spores, insect, animal and other indoor allergens. Thirty-five (63.6%) of the asthmatic children had one or more positive skin reactions. Reactions were most common, and strongest to the indoor and animal panel and to pollens. Fungal reactions were less common and weaker. This represents a lower proportion of skin test-positive asthmatic children than other Western countries. This might relate either to the presence of asthma without atopy, lack of exposure to potential allergens, or lack of appropriate antigens relevant to the disease in the skin test panel.

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.

Passive smoking effects on wheezy bronchitis.

Previous epidemiological studies have associated parental smoking with an increased incidence of lower respiratory illness and bronchial asthma. The aim of the present study was to investigate the association between parental smoking habits and diagnosed wheezy bronchitis in schoolchildren in Saudi Arabia. In a cross-sectional study 3,041 schoolchildren ages seven to 12 years were randomly selected in Dammam, Jeddah, and Riyadh; representing three different geoclimatic regions of Saudi Arabia. Standardized questionnaires were used in our study. The results showed that paternal smoking had a significant effect on the frequency of wheezing when paternal and maternal smoking were considered separately. There was no considerable variation in the parental smoking habits in three areas. The association between passive smoking and diagnosed wheezy bronchitis and frequency of wheezing attacks was highly significant (P<0.0001). Overall, the results tend to confirm that there is a real effect of passive smoking on the respiratory health of children and that paternal smoking is a risk factor for wheezy bronchitis in children.

A comparative study of immediate skin test reactivity to inhalant allergens in asthmatic children of two different regions in Saudi Arabia.

The skin test reactivities to various inhalant allergens in asthmatic children from two different regions in Saudi Arabia were compared. One hundred-twenty subjects each from the Central and Western regions, representing different environmental features, were selected. Prick test reactivity to 24 common allergens were analyzed and compared. Seventy-one (59.2%) patients from Riyadh (Central region) showed positive skin reactions to one or more allergens, while 87 (72.5%) reacted positively to different allergens from Makkah (Western region). The distribution of skin test sensitivity revealed striking differences in the two groups. The most prominent were reactions to the house dust mite (D. farinae) which amounted to 56.3% and to fungal allergens, 31.3% in asthmatics from the Western region, while reactions to the same allergens in subjects from the Central region were 10% and 5.8%, respectively. Similarly, marked variations were noted with pollen grain allergens with 9.3% in Central region and 15.4% in the Western region. The study indicates the presence of different allergen profiles in the two regions and suggests the influence of climatic and environmental factors and their impact on sensitization of susceptible subjects.

Airborne Alternaria spores: Potential allergic sensitizers in Saudi Arabia.

BACKGROUND: In order to investigate the role of airborne Alternaria spp. in the sensitization of individuals having respiratory allergy symptoms, particularly bronchial asthma, an aerobiologic and clinical (diagnostic) study was conducted at several centers in Saudi Arabia. MATERIALS AND METHODS: Airborne Alternaria spores were studied at four different centers in Riyadh, Jeddah and Al-Khobar, including three years at one site. Skin prick tests (SPT) were conducted on a total of 616 allergic individuals attending allergy clinics at six different hospitals in Abha, Qassim, Gizan, Jeddah, Hofuf and Makkah regions. RESULTS: Alternaria spores constituted between 1.9%-9.6% of the total fungal air spora, and the maximum concentration exceeded 5x10 2 spores per m3 of air in Jeddah, followed by 4.9x102 spores per m3 in Al-Khobar. Mean weekly and monthly concentration of Alternaria fluctuated, reaching up to 150 spores per m 3 and 60 spores per m 3, respectively. Quantitative regional variations were also recorded. IgE-mediated SPT reactivities conducted on allergic patients resulted in an overall 21.6% positive reactions, showing mild, moderate and strong wheal and erythema. CONCLUSION: The findings reveal that Alternaria spores are prevalent as a major component in the outdoor environment of the Kingdom, with peaks in April and October. The overall 21.6% positive SPT reactions indicate the sensitization level or cross-reactive sensitivity to Alternaria allergens. The study suggests that airborne Alternaria can be a potential allergic sensitizer in susceptible individuals and can be a risk factor in sensitized individuals with symptoms of bronchial asthma and allergic rhinitis in the Kingdom of Saudi Arabia.

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.

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.

Human sensitization to Prosopis juliflora antigen in Saudi Arabia.

BACKGROUND: Allergenicity to Prosopis juliflora pollen antigen has been reported from only a few countries, including the US, South Africa, India and Kuwait. In some parts of Saudi Arabia, species of Prosopis have been introduced by the millions as roadside ornamentation. There appear to be four flowering seasons during which pollen grains float in all directions. However, the role of Prosopis pollen as the sensitizing and/or triggering agent of allergic asthma and/or rhinitis in the Kingdom has never been evaluated. PATIENTS AND METHODS: A total of 473 allergic patients suffering from bronchial asthma in four different geographical regions (Abha, Qassim, Hofuf and Gizan), and attending allergy clinics and chest disease centers of university and Ministry of Health hospitals in the region were tested for immediate hypersensitivity reaction to Prosopis juliflora allergens. Airborne pollen grains at one center were also studied for one full year, using volumetric sampling techniques. RESULTS: A total of 76.1% patients in Qassim, 37.5% in Gizan, 29% in Abha and 11% in Hofuf reacted positively to Prosopis antigen. Multiple sensitivities to other pollen antigens were detected in all patients. The level of airborne Prosopis pollen detected in Gizan exceeded 90 grains m -3 of air. CONCLUSION: In view of the documented evidence of Prosopis-involved allergenicity, the role of Prosopis pollen as a sensitizing factor in Saudi Arabia has been confirmed. However, the cause of elicitation of symptoms in many multiple sensitive patients, together with the question of cross-reactivities, needs thorough and detailed investigation. In vitro confirmation of all positive results is also required to incriminate Prosopis as one of the major allergens in parts of Saudi Arabia.

Epidemiology of asthma and allergic rhinitis in two coastal regions of Saudi Arabia.

In a study of 1953 school children living in two coastal urban areas of the Kingdom of Saudi Arabia, we used a questionnaire to collect details of age, sex, areas of residence, occupation, education, social class, parental history of asthma and information relating to parental smoking habit. The relative importance of those factors on the likelihood of children having bronchial asthma was assessed using logistic regression and a linear modelling analysis. The extent to which these factors affected the severity of bronchial asthma was also examined. A number of statistically significant associations between bronchial asthma and "breathlessness" (P less than 0.001), "Fathers smoker" (P less than 0.001), "usually cough" (P less than 0.001), "pets" (P less than 0.001), "Family history of allergy" (P less than 0.01), were found.

Growth patterns in Saudi Arabian children.

The measurements of head and chest circumferences of 6623 Saudi Arabian pre-school children are presented for the first time. The data were collected through a large scale cross-sectional growth study carried out in Riyadh, the capital of the Kingdom of Saudi Arabia. The results indicate that the average head and chest circumference measurements of the girls were smaller than the boys in all age groups. The analysis of variance results confirmed that these differences were statistically significant. The date indicated that among the average-build (the 50th centile) pre-schoolers, the head circumference measurements of the newborns were larger than the chest circumference measurement by 4.5%. By one year of age, these measurements were equal. After one year, the chest circumference grew larger than the head circumference. However, among the small-build preschoolers (the 3rd centile), the chest circumference measurements did not reach the head circumference measurements until nearly 30 months after birth.

Asthma patterns in Saudi Arabian children.

In a study of 2006 school children living in two urban areas of the Kingdom of Saudi Arabia, we used a questionnaire to collect details of age, sex, areas of residence, occupation, education, social class, parental history of asthma and information relating to parental smoking habit. The relative importance of these factors on the likelihood of children having bronchial asthma was assessed using a linear modelling analysis. The extent to which these factors affected the severity of bronchial asthma was also examined. A number of statistically significant associations between bronchial asthma and 'breathlessness' (P less than 0.0087), 'Father smoker' (P less than 0.0001), 'usually cough' (P less than 0.0001), 'pets' (P less than 0.0067) and 'Family history of allergy' (P less than 0.007), were found.

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.

Sensitization to indigenous pollen and molds and other outdoor and indoor allergens in allergic patients from saudi arabia, United arab emirates, and Sudan.

BACKGROUND: : Airborne allergens vary from one climatic region to another. Therefore, it is important to analyze the environment of the region to select the most prevalent allergens for the diagnosis and treatment of allergic patients. OBJECTIVE: : To evaluate the prevalence of positive skin tests to pollen and fungal allergens collected from local indigenous plants or isolated molds, as well as other outdoor and indoor allergens in allergic patients in 6 different geographical areas in the Kingdom of Saudi Arabia (KSA), the United Arab Emirates, and Sudan. MATERIAL AND METHODS: : Four hundred ninety-two consecutive patients evaluated at different Allergy Clinics (276 women and 256 men; mean age, 30 years) participated in this study. The selection of indigenous allergens was based on research findings in different areas from Riyadh and adjoining areas. Indigenous raw material for pollen grains was collected from the desert near the capital city of Riyadh, KSA. The following plants were included: Chenopodium murale, Salsola imbricata, Rumex vesicarius, Ricinus communis, Artiplex nummularia, Amaranthus viridis, Artemisia monosperma, Plantago boissieri, and Prosopis juliflora. Indigenous molds were isolated from air sampling in Riyadh and grown to obtain the raw material. These included the following: Ulocladium spp., Penicillium spp., Aspergillus fumigatus, Cladosporium spp., and Alternaria spp. The raw material was processed under Good Manufacturing Practices for skin testing. Other commercially available outdoor (grass and tree pollens) and indoor (mites, cockroach, and cat dander) allergens were also tested. RESULTS: : The highest sensitization to indigenous pollens was detected to C. murale (32%) in Khartoum (Sudan) and S. imbricata (30%) and P. juliflora (24%) in the Riyadh region. The highest sensitization to molds was detected in Khartoum, especially to Cladosporium spp. (42%), Aspergillus (40%), and Alternaria spp. (38%). Sensitization to mites was also very prevalent in Khartoum (72%), as well as in Abu Dhabi (United Arab Emirates) (46%) and Jeddah (KSA) (30%). CONCLUSIONS: : The allergenicity of several indigenous pollens and molds derived from autochthonous sources was demonstrated. Prevalence studies in different regions of KSA and neighbor countries indicate different sensitization rates to these and other outdoor and indoor allergens.