[Cutaneous leishmaniasis following military deployment to Iraq]

Cutaneous leishmaniasis (CL) is a parasitic disease of the tropics and subtropics, transmitted by bites of infected female phlebotonine sandflies. Although CL lesions are normally self-healing they may be disfiguring or potentially disabling, and in field conditions may become secondarily infected; clinical intervention is appropriate in these circumstances. We describe two soldiers normally stationed in British Forces Germany who following deployment to Iraq presented with Leishmania tropica infection. The primary prevention of CL is discussed, together with the epidemiology of the disease, and its treatment under deployed conditions. Old World CL rarely requires aggressive antimonial terapy. Antiiosis with or without curettage is a simple, safe and effective field treatment.

Compound heterozygosity for mutations in the hairless gene causes atrichia with papular lesions

BACKGROUND

Congenital atrichias represent a complex and heterogeneous group of genodermatoses, which have been shown in several consanguineous families to result from homozygous mutations in the hairless gene (HR).

OBJECTIVES

To identify the molecular basis of congenital atrichia in a non-consanguineous family.

METHODS

Genetic analysis was carried out in a two-generation family with two children with congenital atrichia and one healthy child.

RESULTS

We established a diagnosis of atrichia with papular lesions based on clinical and histopathological data. We identified a heterozygous 11-bp deletion (189-199del) in the two affected children and their mother. In addition, the two affected children and their father were shown to carry a non sense mutation (Q478X), which has previously been described in a Pakistani family. Haplotype analysis revealed that mutation Q478X occurred independently in the two families.

CONCLUSIONS

We have identified the first case of compound heterozygosity for mutations in HR as well as the first instance of a recurrent mutation in this gene. These data further expand our understanding of the molecular pathomechanisms underlying congenital atrichias.

An analysis of skin prick test reactions in asthmatics in a hot climate and desert environment

BACKGROUND

Studies have shown that allergens are very important sensitizing agents in patients with asthma. Respiratory disorders such as asthma and allergic rhinitis are common in the United Arab Emirates, (UAE).

OBJECTIVES

The aim of this study was to investigate the relationship between allergen specific IgE antibodies and skin test reactivity in patients with asthma in hot climate and desert Arabian country.

DESIGN

A hospital-based prospective study conducted.

SETTING

Tawam Teaching Hospital, Al-Ain, UAE.

PATIENTS

327 adult patients recruited with respiratory, dermatologic and ophthalmologic diseases of suspected allergic origin who attended Tawam Teaching Hospital of Faculty of Medicine, Al Ain, UAE, during three years from 1996 to 1998.

METHODS

Skin Prick Test (SPT) and radioallegosorbent tests (RAST) were performed on 327 patients for common allergens. The blood sample was taken for measuring specific IgE concentration.

RESULTS

There were 327 UAE patients of whom 117 (35.8%) were males and 210 (64.2%) were females. The population sample had a higher prevalence of diagnosed asthma among females (48.1%) than in males (36.7%). Skin prick testing showed that 244 patients (74.6%) had positive results, and 83 patients (25.4%) were found to be skin test negative. 44% had a positive family history of asthma. The twelve most common reactions in the United Arab Emirates were: Mesquite (45.5%), Grass Mix (40.7%). Cottonwood (33.1%), Bermuda Grass (31.3%), Kochi (25.8%), Acacia (25.6%), Alfalfa (22.9%), Chenopodium (19.6%), Date palm (13.8%), Cockroach (14.7%), house dust (11.9) and Dust mite (9.5%). Total IgE level (> 100 kU/l) was strongly associated with history of wheeze (p = 0.019), asthma (p = 0.01) and allergic rhinitis (p < 0.0001), atopy (p < 0.0001) and the presence of specific IgE antibodies to grass pollen (p < 0.0001), mite (p = 0.008) and cockroaches (p = 0.025).

CONCLUSION

The present study revealed that hypersensitivity to pollens, house dust, dust mite and cockroach was common. The family history, environment, and airborne allergens are identified to be risk factors for asthma and other allergic diseases in Arabian Gulf Countries.

X-linked dyskeratosis congenita: restrictive pulmonary disease and a novel mutation

Dyskeratosis congenita (DC) is a rare inherited multisystem disorder characterised by lesions of the skin and appendages. Bone marrow failure occurs in 80% of patients. The gene for the X-linked form of DC has been identified on Xq28 and designated as DKC1. Pulmonary manifestations have rarely been reported. It is not known whether there is a respiratory disease peculiar to these patients and, if so, whether it is associated with a specific genetic mutation. A 40 year old Egyptian man with pulmonary disease and his symptom free 35 year old brother both presented with mucocutaneous lesions characteristic of DC. In the older brother chest imaging revealed generalised intralobular interstitial thickening and honeycombing. Pulmonary function tests showed a restrictive pattern. Open lung biopsy specimens of lung tissue showed various degrees of fibrosis consistent with usual interstitial pneumonia of chronic idiopathic pulmonary fibrosis. The younger brother was free of pulmonary lesions. Both had a novel missense mutation 5C-->T in exon 1 of the DKC1 gene. It is concluded that pulmonary disease in DC may be underestimated, possibly because most patients die at an early age of bone marrow failure. No relationship between genotype and phenotype could be established in the patients studied. The genetic diagnosis of DC is now available, which may enable it to be diagnosed in patients with restrictive pulmonary disease and minimal cutaneous signs.

Association of acanthosis nigricans with risk of diabetes mellitus, and hormonal disturbances in arabian females: case-control study

OBJECTIVE

To aim of the present study is to determine the association of acanthosis nigricans(AN) with risk of diabetes mellitus, and hormonal levels in female subjects from the United Arab Emirates (UAE).

DESIGN

Matched case-control study.

SETTING

Tawam Teaching Hospital of Faculty of Medicine and Health Sciences.

SUBJECTS

184 female subjects (92 females with AN and 92 females without AN); (age range 16-65 years) were recruited.

METHODS

Height, weight, and sitting blood pressure were recorded on 184 female subjects with AN and without AN. Fasting blood samples were obtained for measurement of uric acid, glucose, cholesterol, HDL-cholesterol, and triglyceride levels.

MAIN OUTCOME MEASURE

Risk factors were investigated. Analysis was based on univariate and multivariate analysis.

RESULTS

The present study showed that BMI, family history of DM, fasting glucose, HDL-cholesterol (mmol/l), triglycerides (mmol/l) and uric acid (mmol/l) levels were statistically significantly higher in obese women in acanthosis and non acanthosis groups. The results revealed that BMI, family history of DM, total cholesterol (mmol/l), triglycerides (mmol/l) and uric acid (mmol/l) levels were statistically significant higher in diabetic women in non-acanthosis. Furthermore, systolic blood pressure, total cholesterol (mmol/l), triglycerides (mmol/l) and uric acid (mmol/l) levels were statistically significantly higher in diabetic women in acanthosis groups. Overall, DM subjects had significantly higher values for hormone levels of TSH, FSH, LH, progesterone, testosterone, cortisol, prolactin, GH, and ferritin.

CONCLUSION

The conclusion has been stated as follows: patients in the UAE who have AN have a high prevalence of DM and insulin resistance. Since AN is rather prevalent in the UAE, identifying this skin lesion can help detect those subjects with a higher risk of DM and hormonal disturbances.

Cutaneous nocardiosis of the chest wall and pleura--10-year consequences of a hand actinomycetoma

We report an unusual case of primary cutaneous nocardiosis due to Nocardia otitidiscaviarum presenting first as a mycetoma of the right hand and wrist. The patient refused treatment and was lost to follow-up until he showed up 10 years later with numerous discharging large sinuses and abscesses on the upper right quadrant of the chest wall and in the right armpit. Roentgenograms revealed pleural masses. Histology was in keeping with the diagnosis of mycetoma. Treatment with amikacin, rifampicin and co-trimaxole proved to be successful.

Congenital insensitivity to pain with anhidrosis

Congenital insensitivity to pain with anhidrosis is an autosomal-recessive disorder resulting from defective neural crest differentiation with loss of the first-order afferent system, which is responsible for pain and temperature sensation. There is also a neuronal loss in the sympathetic ganglia. Lack of sweating, hyperthermia, and infections of bones are main features of the disorder; however, contradictory results have been published regarding eccrine sweat gland innervation. A 5-year-old male patient with typical clinical manifestations of congenital insensitivity to pain with anhidrosis is presented. Immunohistochemistry with antibodies against S100 protein and neuron-specific enolase failed to reveal nerve fibers in the vicinity of the eccrine sweat glands. The roles of the nerve growth factor and tyrosine kinase receptor gene mutations in the pathogenesis of the disease are also discussed.

Etiology of toe-web disease in Al-Ain, United Arab Emirates: bacteriological and mycological studies

Wexamined and sampled 45 patients with toe-web intertrigo for bacteriological and mycological studies. Prominent isolated pathogens were the genus Candida [57.7%], genus Aspergillus [28.8%], Pseudomonas aeruginosa [26.7%] and coliforms [24.4%]. Dermatophytes scored 4.4% [Trichophyton rubrum]. There were 43 patents [95.5%] who presented with marked hyperkeratosis and maceration of the toe-webs involved. The tradition of the Emirati population of sitting cross-legged may, over time, induce in the toe-webs of overweight individuals a macerated pressure-reaction hyperkeratosis that is colonized by environmental germs. T. rubrum and T. mentagrophytes are uncommon in the Al-Ain environment and this may explain the rarity of dermatophytes in toe-web intertrigo in our study.

Haplotypes of the human renin gene associated with essential hypertension and stroke

The human renin gene (REN) is a good candidate in studies aimed at unravelling the genetic basis of essential hypertension and stroke. We previously established that both a BglI and an MboI dimorphisms (located respectively in the first and ninth introns of the REN gene) were associated with essential hypertension in a population of hyperlipidaemic US subjects. In this association (retrospective case-control) study, we investigated the haplotype distribution of alleles defined by the combination of REN BglI and MboI dimorphic sites in 329 hyperlipidaemic US Caucasian subjects referred to UCSF Medical Center (140 hypertensives, 141 normotensives, and 48 hypertensive patients who had suffered a stroke). A statistically significant association was found between alleles determined by both (BglI(-)/MboI(+)) and (BglI(+)/MboI(+)) haplotypes and clinical diagnosis of EHT (combined odds ratios, OR = 3.35, corrected P < 10(-7)). Haplotypes (-,+) and (+,+) were also found to be associated with clinical diagnosis of stroke (OR = 4.31, P < 10(-7)). These associations do not occur through the effects of classical risk factors related to lipid, lipoprotein and apolipoprotein levels. We conclude that variations of the REN (or of a nearby) gene that may be in linkage disequilibrium with REN (BglI(-)/MboI(+)) and (BglI(+)/MboI(+)) alleles could play a role in contributing to increased individual's genetic susceptibility to EHT and to stroke. Journal of Human Hypertension(2001) 15, 49-55

Etiology of toe-web disease in Al-Ain, United Arab Emirates: bacteriological and mycological studies

We examined and sampled 45 patients with toe-web intertrigo for bacteriological and mycological studies. Prominent isolated pathogens were the genus Candida (57.7%), genus Aspergillus (28.8%), Pseudomonas aeruginosa (26.7%) and coliforms (24.4%). Dermatophytes scored 4.4% (Trichophyton rubrum). There were 43 patents (95.5%) who presented with marked hyperkeratosis and maceration of the toe-webs involved. The tradition of the Emirati population of sitting cross-legged may, over time, induce in the toe-webs of overweight individuals a macerated pressure-reaction hyperkeratosis that is colonized by environmental germs. T. rubrum and T. mentagrophytes are uncommon in the Al-Ain environment and this may explain the rarity of dermatophytes in toe-web intertrigo in our study.

Association of Acanthosis nigricans with risk of diabetes mellitus and hormonal disturbances in females

OBJECTIVE

To determine the association of Acanthosis nigricans, hyperinsulinemia, and hormonal levels in female subjects from the United Arab Emirates (UAE).

DESIGN

Prospective study.

SETTING

Tawam Teaching Hospital of Faculty of Medicine & Health Sciences.

SUBJECTS

Ninety-two females (age range 16-65 years) were recruited.

METHODS

Height, weight, and sitting blood pressure were recorded on 92 female subjects with A. nigricans. Fasting blood samples were obtained for measurement of uric acid, glucose, cholesterol, high-density lipoprotein- (HDL) cholesterol, and triglyceride levels. Serum levels of thyroid stimulating hormone (TSH), testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin are obtained by radio-immunoassay.

RESULTS

Ninety-two females with A. nigricans were enrolled in the study. Of the 92 females, 36 subjects were considered to have diabetes mellitus (DM) and 56 euglycemic subjects. The analysis showed that in cases of family history of DM, HDL-cholesterol (mmol/l) and uric acid (mmol/l) levels were higher. Overall, DM subjects had significantly higher values for hormone levels of TSH, FSH, LH, progesterone, testosterone, cortisol, prolactin, (growth hormone) GH, and ferritin.

CONCLUSION

Patients with A. nigricans have a high prevalence of DM and insulin resistance in UAE. Since A. nigricans is rather prevalent in the UAE, identifying this skin lesion can help detect those subjects with a higher risk of DM and hormonal disturbances.

Diffuse calcinosis cutis in a patient with congenital leukemia and leukemia cutis

We report an unusual case of congenital leukemia with leukemia cutis (LC) and diffuse calcinosis cutis. A newborn girl presented with widespread dusky red and yellowish cutaneous nodules and papules. Bone marrow morphology was consistent with the diagnosis of acute monocytic leukemia of the FAB M5 type. Skin biopsy specimens confirmed the presence of a leukemic infiltrate and revealed calcium salt deposition in the papillary and reticular dermis. Calcinosis was diffuse in the whole skin but spared other organs. Vascular calcification was not present. Serum calcium levels oscillated between 2.5 and 2.86 mmol/l, and phosphorus, parathyroid hormone and 25-hydroxyvitamin D(3) levels were normal. There were diffuse osteoporosis and spontaneous fractures of small tubular bones. The patient responded to chemotherapy but, following consolidation treatment, developed sepsis and died at 120 days of age. Congenital leukemia is rare and LC is uncommon. Hypercalcemia may be a complication of leukemia, which leads to multiorgan metastatic calcification. Despite the absence of frank hypercalcemia, the presence of bone lesions suggests that the patient's calcinosis cutis was of the metastatic type. However, the cutaneous leukemic infiltrate may also represent a triggering factor for calcium deposition in the skin.

Abnormal myelin formation in rhizomelic chondrodysplasia punctata type 2 (DHAPAT-deficiency)

The case of a Yemeni girl with isolated peroxisomal acyl-CoA:dihydroxyacetonephosphate acyltransferase (DHAPAT) deficiency is reported. She had rhizomelic chondrodysplasia punctata, microcephaly, failure to thrive, delayed motor and mental development, and spastic quadriplegia. Deficient de novo plasmalogen synthesis in her fibroblasts as a result of low DHAPAT activity was found, while her very-long-chain fatty acid profile, phytanic acid concentration, alkyl-dihydroxyacetonephosphate synthase (alkyl-DHAP synthase) activity, and peroxisomal 3-ketoacyl-CoA thiolase protein were normal. A mutation in her DHAPAT complementary DNA resulted in the substitution of an arginine residue in the protein at position 211 by a histidine (R211H). Magnetic resonance imaging showed abnormal white matter signal in the centrum semiovale involving the arcuate fibers, while the corpus callosum was normal. DHAPAT and alkyl-DHAP synthase initiate the synthesis of plasmalogens, which are major constituents of myelin phospholipids. The reported girl's abnormal formation of myelin is probably related to the inadequacy of plasmalogen biosynthesis, which is likely to be due to deficient DHAPAT activity.

Identification of cystic fibrosis mutations in the United Arab Emirates. Mutations in brief no. 133. Online

We have designed a study aimed at identifying the genetic mutations responsible for cystic fibrosis (CF) in the population of the United Arab Emirates. The prevalence of CF in the UAE is at least 1/15,000 live births and the disease is associated with very severe clinical presentations. We have investigated 17 unrelated families. Ten UAE national families were of Bedouin descent: all 15 CF patients, who presented with very severe forms of the disease, were homozygous for a S549R mutation due to a T->G transversion at nucleotide postion 1779. Amongst a distinct population of Baluch origin, CF patients from 6 out of 7 affected families were DF508 homozyotes. Hence, the unique distribution of CF mutations in the United Arab Emirates--two mutations, S549R and DF508, characterize so far 94% of CF families--should allow efficient organizing and delivering of CF carrier screening programmes on the country's relatively limited population size.

Acanthosis nigricans, hyperinsulinaemia and risk factors for cardiovascular disease

We examined the association between acanthosis nigricans, hyperinsulinaemia and other risk factors for cardiovascular disease in patients from the United Arab Emirates. Height, weight and sitting blood pressure were recorded in 122 patients with acanthosis nigricans, and blood samples were obtained for measuring fasting cholesterol, high-density lipoprotein cholesterol, triglyceride and uric acid levels. In addition, a glucose tolerance test was performed and blood was sampled for insulin and glucose. Our results indicate that the patients with acanthosis nigricans had a high prevalence of abnormal glucose tolerance and hyperinsulinaemia. In addition, euglycaemic patients with hyperinsulinaemia had a cluster of risk factors for cardiovascular disease

Acanthosis nigricans, hyperinsulinaemia and risk factors for cardiovascular disease

We examined the association between acanthosis nigricans, hyperinsulinaemia and other risk factors for cardiovascular disease in patients from the United Arab Emirates. Height, weight and sitting blood pressure were recorded in 122 patients with acanthosis nigricans, and blood samples were obtained for measuring fasting cholesterol, high-density lipoprotein cholesterol, triglyceride and uric acid levels. In addition, a glucose tolerance test was performed and blood was sampled for insulin and glucose. Our results indicate that the patients with acanthosis nigricans had a high prevalence of abnormal glucose tolerance and hyperinsulinaemia. In addition, euglycaemic patients with hyperinsulinaemia had a cluster of risk factors for cardiovascular disease.

Human renin gene BglI dimorphism associated with hypertension in two independent populations

The renin (REN) gene is a good candidate that could underlie an individual's genetic susceptibility to human essential hypertension (EHT). We describe here a polymerase chain reaction-based assay for detection of a BglI dimorphic site located in the first intron of the REN gene. In this retrospective, case-control, association study, we investigated BglI allele and genotype distributions in 554 subjects (280 hypertensives and 274 normotensives) from the United Arab Emirates (UAE) - a genetically homogeneous ethnic population with no history of smoking or alcohol consumption - and in 485 hypercholesterolemic, US Caucasian subjects (250 hypertensives and 235 normotensives). A statistically significant association was found between alleles on which the BglI site is present [BglI(+)] and clinical diagnosis of EHT in the UAE sample group (odds ratio = 2.69, p = 0.0006), and a similar trend was observed in the US group (odds ratio = 1.97, p = 0.01). BglI(+) homozygous status was also investigated in the US group and found to be associated with elevated systolic and diastolic blood pressure values (respectively, 144.8+/-26.1 vs. 134.1+/-23.0 mm Hg, p = 0.04; and 91.0+/-12.5 vs. 82.2+/-12.7 mm Hg, p = 0.009). In conclusion, variations of the REN (or of a nearby) gene that may be in linkage disequilibrium with the REN BglI(+) marker could play a role in contributing to an increased individual's genetic susceptibility to EHT in the UAE population and amongst US hypercholesterolemic Caucasians. Such a genetic influence, which seems to show a recessive mode of inheritance, could also be implicated in raising both systolic and diastolic blood pressures.

Analysis of the apolipoprotein B gene 3' hypervariable region among nationals of the Abu Dhabi Emirate and comparisons with other populations

BACKGROUND

Among all the polymorphic markers available to date, a hypervariable region located in the 3' of the human apolipoprotein B gene has been extensively studied in global populations throughout the world.

PATIENTS AND METHODS

Using a polymerase chain reaction-based assay, we investigated the allele and genotype frequency distributions of the alleles (corresponding to repeats of a 30 base-pair core DNA sequence) of this hypervariable region in a group of 367 unrelated nationals (201 males, 166 females) from the United Arab Emirates.

RESULTS

We found 18 different alleles, ranging from 21 to 55 repeats, making up 51 genotypes that occurred in Hardy-Weinberg proportions and were associated with a heterozygosity index of 80.9%. The allele frequency distribution was different from that of other populations in that it was trimodal, with peaks at 31, 37 and 47 repeats, with corresponding relative frequencies of 16.1%, 25.1% and 6.0%. A four-allele model, which allowed comparisons with other reports, revealed distribution differences with all other ethnic groups except South Asians and Serbs.

CONCLUSION

This marker is very informative for the Emirati population, and will be very useful for UAE-specific DNA fingerprinting. It will also be a valuable tool for assessing the role of apolipoprotein B in cardiovascular diseases.

Atrichia with papular lesions resulting from a nonsense mutation within the human hairless gene

Atrichia with papular lesions is a rare autosomal recessive form of alopecia characterized by hair loss soon after birth and the development during childhood of a diffuse papular rash. We have previously shown that this disorder results from a deleterious mutation in the human hairless gene, a gene also involved in the pathogenesis of a related but clinically distinct form of congenital alopecia, termed alopecia universalis congenita. In this report, we describe a novel nonsense mutation in exon 4 of the human hairless gene in a consanguineous kindred affected with atrichia with papular lesions. This report provides additional evidence for phenotypic heterogeneity among inherited atrichias and for an association between the papular rash of atrichia with papular lesions and nonsense mutations in the human hairless gene.

A clinical study of airborne allergens in the United Arab Emirates

BACKGROUND

In the past 25 years the United Arab Emirates (UAE) have experienced a socioeconomic boom. The once nomadic Bedouin population of Al Ain, in the emirate of Abu Dhabi, now lives in modern air-conditioned accommodation, and huge desalination plants have allowed afforestation and farming.

OBJECTIVE

To evidence responsible airborne allergens in an UAE population.

PATIENTS AND METHODS

263 UAE Nationals who attended Tawam Hospital (Al Ain, UAE) with a respiratory disease suspected of being of allergic origin, were submitted to SPT and RAST. The choice of pollinic allergens was made in accordance with the local flora and market availability. All patients were SPTed with at least the same battery of 15 pollinic and indoor allergens. Most patients were submitted to at least 4 RAST, viz Cynodon dactylon, Salsola kali, Prosopis juliflora and Dermatophagoides pteronyssinus.

RESULTS

71.8% patients were positive for at least one allergen. Pollen accounted for 61.6% of positive patients, with 45.2% positive to chenopodiaceae, 33% to gramineae and 23.5% to P. juliflora. Indoor allergens were positive in 30.4% of patients with 17.9% positive to D. pteronyssinus and D. farinae, 11% to Blatella germanica, 8.3% to Cat fur, 4.9% to Goat hair, 0.7% to Rat hair and Mouse hair and 1.5% to Candida albicans.

CONCLUSION

Pollen was the prominent allergen. There is room, however, for further epidemiological studies possibly with new extracts and RAST specifically designed after the species of the Gulf region.

Association of an apolipoprotein B gene marker with essential hypertension

We designed an association (retrospective, case control) study aimed at evaluating associations between genetic variations of the human apolipoprotein B (apoB) gene and clinical diagnosis of essential hypertension. Our approach was to compare the distribution of the alleles of a highly polymorphic variable number of tandem repeats localized 3' to the human apoB gene, the apoB 3' hypervariable region (HVR), in a group of normotensive and a group of hypertensive individuals. We collected DNA samples from 437 unrelated nationals (215 normotensives and 222 hypertensives) from the United Arab Emirates (UAEs), and we determined their apoB 3' HVR allele and genotype status with a polymerase chain reaction-based assay. In the UAE population, we found 18 alleles underlying a total of 51 genotypes. The distribution of these alleles was significantly different between normotensive and hypertensive UAE nationals. The main peak of the distributions occurred at 35 repeats among hypertensives (with a relative frequency of 25.7% versus 19.6% in normotensives) and at 37 repeats among normotensives (28.8% versus 20.3% in hypertensives). Alleles with 21, 23, 25, 49, and 55 repeats were found in hypertensives only (with a combined relative frequency of 7.6%). We conclude that variations of the apoB gene, or of a nearby gene, that may be in linkage disequilibrium with these alleles play a role in the development of essential hypertension in the UAEs.

Allergic contact dermatitis in the United Arab Emirates

BACKGROUND

No data exist on allergic contact dermatitis (ACD) in the United Arab Emirates (UAE).

AIM

Our aim was threefold: (i) to determine the incidence of ACD; (ii) to identify responsible allergens using the European Standard Series, TRUE TEST, and other substances; (iii) to tentatively explore population-specific reactions in Al Ain, UAE.

DESIGN

This is a prospective, descriptive, hospital-based, study.

SETTING

Tawam Hospital, Al Ain Medical District, UAE.

PATIENTS

During the years 1989-1996, 373 patients (male: female = 2 : 3), presenting with cutaneous manifestations possibly related to contact allergy, were patch tested.

RESULTS

93.8% of patients presented with dermatitis affecting mostly the hands (45.1%), feet (21.4%), face (12.6%), and legs (4.6%). Two hundred and twenty-four patients (60%) (male : female = 1 : 2) tested positive for at least one substance. Nickel was the commonest sensitizer (15%) in both genders. "Fragrance mix" (8%), p-tertiary butylphenolformaldehyde (p-TBPF) resin (7.5%), thiomersal (7.5%), chromium (7.2%), cobalt (6.4%), ethylenediamine (6.4%), neomycin (5.1%), and parabens (5.1%) were prominent allergens. Glutardialdehyde, an additional substance tested together with the European Standard Series, scored significantly (4.8%). Variations from the results reported from other countries may be explained by the specific lifestyles and customs of the UAE population.

CONCLUSIONS

Substances contained in the TRUE TEST, plus glutardialdehyde, may be considered as the standard series for patch testing in the UAE population.

Respiratory symptoms, skin disorders and serum IgE levels in farm workers

The aim of this study is to evaluate the prevalence of dermo-respiratory symptoms from lung-function spirometer values and serum IgE levels in farmers who have been exposed to pesticides in the United Arab Emirates (E.A.U.). The study was a comparison of 98 farmers with 98 non-farmers, the two groups were equivalent in age, sex and selected regions--the town of Al-Ain and in the Emirates of Dubai, Sharjah and Fujairah. Most of the farmers were illiterate or poorly educated (p < 0.0001). Most lived in prefabricated houses (50.5%). Use of chemical substances (70.9%) and a mixture of pesticides by the farmers (60.2%) was very high. The results revealed that the farmers had a very high prevalence of chronic dermo-respiratory symptoms. These differences are statistically significant when compared with the reference group, particularly for the following symptoms: cough (p < 0.003), pharyngitis (p < 0.0003), bronchitis (p < 0.02), asthma (p < 0.008), respiratory insufficiency (p < 0.006), pneumonia (p < 0.003), dyspnea (p < 0.006), nasal catarrh (p < 0.001), sinusitis (p < 0.05), pharyngeal irritation (p < 0.01), nasal irritation (dryness, sneezing and secretions) (p < 0.005), ocular irritation (p < 0.05), cutaneous pruritus (p < 0.002), and contact dermatitis (p < 0.02). The spirometer tests (all parameters together) measured in the farmers were significantly reduced by comparison with the reference group. In conclusion, the authors suggest that a high prevalence of dermo-respiratory symptoms, supported by reduced spirometer tests and high serum IgE, is associated with exposure to pesticides. These results are clearly useful for establishment of work-related reduced exposure in the future.

Associations of angiotensinogen gene mutations with hypertension and myocardial infarction in a gulf population

To date, the human angiotensinogen (AGT) gene and some of its variants represent the best examples of genetic influences that are involved in the determination of essential hypertension (EH) and associated cardiovascular diseases (CVDs). To assess the value of genotyping AGT in a genetically homogeneous population, we carried out a retrospective, case control study of variants M235T and T174M for putative correlations with CVDs among nationals from the United Arab Emirates (Emirati)--an ethnic group characterized by no alcohol intake and no cigarette smoking. We investigated a sample population of 229 Emirati (119 males and 110 females), comprising groups of controls and patients with clinical diagnoses of EH, left ventricular hypertrophy (LVH), ischaemic heart disease (IHD) and myocardial infarction (MI). M235T and T174M alleles were determined via assays based on the polymerase chain reaction. T174M showed no correlation with any of the four clinical entities included in this study. T235 alleles, however, occurred more frequently in the EH group and less frequently in the group of MI survivors. We also found that T235 allele frequencies decreased with age, indicating that in the Emirati population, T235 alleles are associated with a reduced life span and that this effect could occur through independent mechanisms underlying genetic susceptibilities to both EH and MI.

An MboI two-allele polymorphism may implicate the human renin gene in primary hypertension

As a key enzyme of the renin-angiotensin-aldosterone system, the renin gene (REN) is a good candidate quantitative trait locus that may be implicated in the molecular etiology of essential hypertension. Among mixed reports on the subject, a REN MboI restriction fragment length polymorphism has been shown to be significantly associated with a family history of hypertension in a Japanese population. We show here that the REN MboI dimorphic site is located in the ninth intron of the gene, and we describe a polymerase chain reaction-based assay for detection of this site. We investigated MboI genotype distributions in 331 hypertensive and 279 normotensive subjects from the United Arab Emirates (UAE), a genetically homogeneous ethnic population with no history of smoking or alcohol consumption. A statistically significant association was found between alleles on which the MboI site is present and clinical diagnosis of essential hypertension, indicating that 1) the presence of the MboI site is a marker for susceptibility to hypertension in the UAE (the associated odds ratio is 3.16); and 2) variations of the REN (or of a nearby) gene that may be in linkage disequilibrium with this marker play a role in the development of essential hypertension in the UAE.

Co-existence of leukoderma with features of Dowling-Degos disease: reticulate acropigmentation of Kitamura spectrum in five unrelated patients

BACKGROUND

The spectrum of Dowling-Degos disease-reticulate acropigmentation of Kitamura (DDD-RAK) is a group of rare autosomal dominant disorders that have in common a unique histological picture of hyperpigmented digitate epidermal 'downgrowths'. Patients with the DDD-RAK spectrum may show hyperpigmented macules and papules, facial pits, breaks in dermatoglyphics and epidermoid cysts.

OBSERVATIONS

We examined 5 unrelated patients, 3 females and 2 males (age range 22-35 years), who presented with clinical and histological features of the DDD-RAK spectrum. In addition, the patients presented with hypo- or depigmented macules and papules. Histopathology of the lesions revealed features that were identical to DDD-RAK; there were, however, diminution or absence of pigmentation. Family histories for pigmented lesions and leukoderma were positive in all patients and consistent with autosomal dominant modes of inheritance.

CONCLUSION

These 5 cases, together with isolated reports in the literature of achromic lesions with histological features of DDD-RAK, point to the hypothesis that achromic macules and papules may be a feature of the DDD-RAK spectrum.

Congenital ichthyosis, follicular atrophoderma, hypotrichosis, and hypohidrosis: a new genodermatosis?

Follicular atrophoderma is a rare anomaly observed mainly in the X-dominant form of chondrodysplasia punctata (Conradi-Hünermann-Happle syndrome) and in the X-linked dominant Bazex syndrome. We report on five Emirati sibs (three girls and two boys), 4-18 years old, with normal stature, diffuse congenital ichthyosis, patchy follicular atrophoderma, generalized and diffuse non-scarring hypotrichosis, and marked hypohidrosis. Steroid sulfatase activity, assessed in the two boys, was found to be normal. Electron microscopic studies of ichthyotic skin did not show any specific abnormality. The association of congenital diffuse ichthyosis with follicular atrophoderma and hypotrichosis has not been reported before. The patients were reminiscent of Bazex syndrome; however, ichthyosis is not a component of Bazex syndrome. We conclude that this syndrome of congenital ichthyosis with follicular atrophoderma represents a new autosomal recessive genodermatosis.

The angiotensin-converting enzyme (ACE) gene insertion/deletion dimorphism tracks with higher serum ace activities in both younger and older subjects

BACKGROUND

The absence of a 287 base pair alu sequence in the ACE gene (D allele) is associated with higher ACE levels than its presence (I allele) in adults. We carried out a case-control study of the ACE*I/D dimorphism in relation to circulating ACE activities to evaluate associations between the two variables in adults, compared to younger (18 years or less) individuals.

MATERIALS AND METHODS

Genotypes of the ACE*I/D dimorphism were determined on DNA samples from a population of 164 random (unrelated) Emirate nationals, composed of two groups: 112 subjects above 18 years of age (range=20-77 years), and 52 subjects of 18 years or less (range=1-18), and analyzed for putative associations with serum ACE activities. ACE*I/D genotypes of the 164 individuals were determined by assays based on polymerase chain reaction. ACE activities were determined on serum samples of these subjects by colorimetric assays.

RESULTS

The D allele was associated with increased ACE values in both adult and younger individuals. Mean ACE activity levels associated with II, ID and DD genotypes, however, were 42%-61% higher in the 18 years and under group of subjects. The ACE*I/D marker accounted for 28% of the variance of the phenomenon determining ACE levels in adults, and for 30% among youngsters.

CONCLUSION

The ACE*I/D dimorphism correlated strongly with circulating ACE activities in both adult and young Emirati subjects, and the corresponding mean ACE activities were significantly higher among the youngsters.

Clinical and immunological studies in vitiligo in the United Arab Emirates

OBJECTIVE

To determine the clinical and immunological changes encountered in patients with vitiligo in Al-Ain population, United Arab Emirates (UAE).

DESIGN

This is a prospective descriptive hospital-based study.

SETTING

Al-Ain Medical District, Al-Ain Hospital, United Arab Emirates.

SUBJECTS

Patients who were seen at Al-Ain hospital for skin diseases during 1996.

RESULTS

The study was based on 65 patients. The sample consisted 32 (49%) males and 33 (51%) females. The mean and standard deviation of age for males were 38.6 +/- 13.5 years and for females were 35.1 +/- 15.9 years. Most of the patients were UAE, Omani and Pakistani nationals. Positive family history of vitiligo was found in 19% of the patients. Association with other immune diseases was found in 6% of the patients while one or more organ specific antibodies, all of whom were females, most of them had positive history of autoimmune diseases.

CONCLUSION

Vitiligo is more common among UAE nationals since the UAE community including a multi-national society.

Association study between the ANF gene and hypertension in a Gulf Arab population

We have studied an insertion/deletion (I/D) dimorphism located in the second intron of the human atrial natriuretic factor (ANF) gene among 232 United Arab Emirates (UAE) nationals (112 normotensives and 120 hypertensives) from the Abu Dhabi Emirate, with a view to evaluating the value of this marker in relation to hypertension. Our findings show that genotype frequencies of this I/D marker occur in Hardy-Weinberg proportions (respective genotype frequencies in the overall sample population are: II, 51%; ID, 42%; DD, 7%). No association, however, was evidenced between this dimorphic site and clinical diagnosis of essential hypertension. This suggests that: 1) this I/D dimorphism is not a useful marker to study the relationship between the ANF gene and hypertension in the UAE; and 2) variations of the ANF gene that may be in linkage disequilibrium with this marker do not play a major role in the determination of hypertension in this Arab population.

Variations in lipid and lipoprotein levels during isotretinoin treatment for acne vulgaris with special emphasis on HDL-cholesterol

BACKGROUND

Many studies have demonstrated an increase in total cholesterol and triglycerides on oral isotretinoin therapy. This has led several investigators to comment on the possibility of increased risk for cardiovascular disease. Yet, the status of high density lipoprotein (HDL) in patients on isotretinoin therapy has not been studied extensively.

PATIENTS AND METHODS

We studied 104 United Arab Emirates (UAE) nationals (78 women, 26 men) who underwent isotretinoin therapy for acne at doses ranging from 0.2 to 1.6 mg/kg, and determined the lipid and lipoprotein levels before and after an 8-week period of treatment. The risk for cardiovascular disease was evaluated as the ratio of cholesterol/HDL-cholesterol.

RESULTS

Mean cholesterol, triglycerides, and low density lipoprotein-cholesterol (LDL-cholesterol) levels rose significantly after treatment (p = 0.01) whereas HDL-cholesterol values decreased significantly (p = 0.01). In the entire subject population, the overall risk for cardiovascular disease rose from 3.45 to 3.67, indicating that these subjects remained in the category considered to have "half-average" to "average" risk of cardiovascular disease.

CONCLUSIONS

In young and healthy individuals, significant variations in lipid and lipoprotein levels, resulting from isotretinoin treatment for acne, do not influence the overall risk for cardiovascular disease. Isotretinoin is thus a safe and efficient drug for the treatment of acne in these subjects.

Mal de Meleda: a report of four cases from the United Arab Emirates

Mal de Meleda (MDM), or recessive transgressive palmoplantar keratoderma, is a rare disorder. MDM may have originated as a founder mutation that occurred on the island of Meleda, now Mljet, in Croatia, where it was first described. However, the condition has also been observed in countries distant from Mljet. The presentation of the disease in young patients has not been reported and the progressiveness of the lesions is debated. We examined four young United Arab Emirates nationals patients (ages 7 months to 12 years) who presented with keratoderma palmoplantaris (KPP) and transgressive pachyderma (TP) that had both been present before 1 year of age. KPP and TP were more pronounced in the two oldest patients. Family histories were consistent with autosomal recessive inheritance. The development of MDM lesions appears to be age-related. However, environment and individual factors may also play a role in the development and persistence of the lesions. Molecular genetic studies are necessary to establish whether the broad clinical presentation of the disease is due to allelic or genetic heterogeneities.

Deletion polymorphism in the angiotensin-converting enzyme gene is not associated with hypertension in a Gulf Arab population

We have studied an insertion/deletion dimorphism in the human angiotensin-converting enzyme gene amongst UAE nationals from the Abu Dhabi Emirate. Our findings show lack of association between the I/D allele marker system and clinical diagnosis of essential hypertension, suggesting that variations of the angiotensin-converting enzyme gene do not play a major role in the determination of elevated blood pressure in this Arab population. This agrees with results reported on other ethnic groups.

Serologic tests for treponematoses in the United Arab Emirates

BACKGROUND AND OBJECTIVE

Venereal syphilis is uncommon in the United Arab Emirates (UAE) and other Gulf states in the Middle East. Although nonvenereal syphilis (bejel) has been reported to be endemic in some of these countries, the extent of treponematoses in the UAE is unknown. The objectives were therefore, to investigate those who attended the outpatient clinic of a hospital in the UAE and to establish the seroprevalence of treponematoses and related clinical conditions.

METHODS

One thousand and eighty-four patients were serologically screened with a Rapid Plasma Reagin (RPR) and Treponema pallidum hemagglutination (TPHA) tests. The charts of seropositive and seronegative patients, matched for age and sex, were reviewed and compared for clinical problems.

RESULTS

A total of 47 people tested had antitreponema antibodies. The positivity rates varied considerably and rose with age from 0.36% for persons < 16 years to 8.3% for those > 50 years. Among the seropositive group, there were no obvious clinical signs of bejel on presentation, but osteoarthritis was significantly more common than in the seronegative group.

CONCLUSIONS

In the UAE, although venereal syphilis is uncommon, there is a high seropositivity rate in the > 50-year age range possibly due to old or attenuated bejel.

Defective integrin alpha 6 beta 4 expression in the skin of patients with junctional epidermolysis bullosa and pyloric atresia

Junctional epidermolysis bullosa (JEB) is a heterogeneous group of rare inherited skin disorders in which defects in cell adhesion components cause incomplete formation of hemidesmosomes. We have immunohistochemically examined the skin from ten JEB patients (JEB gravis, n = 4; JEB mitis, n = 3; JEB plus pyloric atresia [JEB/PA], n = 3) using monoclonal antibodies specific for the integrin adhesion receptors alpha 3 beta 1 and alpha 6 beta 4, and for the alpha 3, beta 3, and gamma 2 subunits of the basement membrane ligand, laminin 5. Consistent with our previous reports, only the JEB gravis patients without associated pyloric atresia expressed reduced or absent epitopes for laminin-5 subunits in their epidermal basement membrane. In contrast, all three JEB/PA cases showed abnormalities in integrin alpha 6 beta 4, but not in laminin 5, expression in their basal epidermal cells. Integrin beta 4 subunit was undetectable in the biopsied epidermis of these JEB/PA individuals using five different monoclonal antibodies that recognize both intra- and extracellular epitopes. The absence of the beta 4 subunit in the epidermis of JEB/PA specimens was confirmed by Western blot analysis of tissue extracts. Epidermal expression of the integrin alpha 6 subunit was variable in the JEB/PA patients. Abnormal integrin alpha 6 beta 4 expression may define the subset of JEB cases with pyloric atresia. These results strongly implicate a functional role for alpha 6 beta 4 in the formation of complete hemidesmosomes and in stable adhesion of basal keratinocytes to the basement membrane in vivo.

Coexistence of atopic dermatitis and lichen nitidus in three patients

Lichen nitidus (LN) is an uncommon skin disorder. We observed 3 patients with an association of lichen nitidus and atopic dermatitis (AD), which to the best of our knowledge has not been previously reported in the literature. It remains to be evaluated whether the association of LN and AD is fortuitous or not.

Association between a dimorphic site on chromosome 12 and clinical diagnosis of hypertension in three independent populations

With the aim of identifying putative quantitative trait loci (QTLs) involved in the regulation of blood pressure, we have carried out association studies at a candidate genetic locus-a human pancreatic phospholipase A2 (PLA2) gene localized on chromosome 12. Positive associations were found between the presence of a Taq I dimorphic site localized in the first intron of this gene and hypertension in three sample populations (two from USA and one from Germany). These results indicate that a QTL implicated in determining an individual's genetic susceptibility to hypertension could be present within up to 30 cM of this human PLA2 gene.

Aetiology of onychomycosis in Al Ain, United Arab Emirates

A 1-year study was conducted on 151 patients with finger- or toenail disease attending a dermatology clinic in Al Ain, United Arab Emirates. Nail scrapings and or clippings were collected and investigated with a KOH preparation for direct microscopy and cultured for fungi. Eighty-nine (59%) patients were females. Most females (62%) presented with fingernail disease while in men the toenails were involved in 76%. Fungi were isolated in 78 (52%) of all cases and the fingernails were more commonly positive than toenails. Of the 78 isolates, 49 (63%) were yeasts, including eight Candida species, dermatophytes accounted for 22 (28%) and seven (9%) were other moulds. Non-dermatophyte moulds constituted 20% of male isolates but only 4% of female isolates. Eighty-one per cent of Candida species were from fingernails, while 87% of all the dermatophytes were from toenails.

Larsen syndrome in siblings with consanguineous parents

Two siblings with Larsen syndrome and consanguineous parents are described, both with multiple joint dislocations and the typical facial appearance. Short stature is marked in both children and one had a diaphragmatic hernia which has not been previously described in this condition.

TaqI dimorphic site in a human pancreatic phospholipase A2 (PLA2) gene localized on chromosome 12

We report the identification of a TaqI dimorphic site in the first intron of a human phospholipase A2 gene that has been localized on chromosome 12. This single two-allele polymorphism was detected by DNA blot hybridization using a full-length, 584 bp human phospholipase A2 cDNA isolated from a human lung lambda gt10 cDNA library. Fragment lengths were detected at either 1.3 kb or 2.2 kb. The PIC value of this dimorphism was 0.369 in a random population of 353 Caucasians.