The prevalence of chronic obstructive pulmonary disease in Riyadh, Saudi Arabia: a BOLD study.

OBJECTIVE: To estimate the prevalence and associated risk factors of chronic obstructive pulmonary disease (COPD) in Saudi adults aged ⩾40 years using standardised post-bronchodilator spirometry according to the Burden of Obstructive Lung Disease (BOLD) protocol. METHODS: Saudi men and women aged ⩾40 years were recruited by stratified multistage random sampling in Riyadh, Saudi Arabia. Participants completed questionnaires on respiratory symptoms and exposure to risk factors for COPD. Spirometry was performed according to standard methods. COPD was defined as post-bronchodilator FEV1/FVC (forced expiratory volume in 1 s/forced vital capacity) ratio <70% (Global Initiative for Obstructive Lung Disease [GOLD]) or less than the lower limit of normal (LLN) (95(th) percentile) of the population distribution for FEV1/FVC. RESULTS: Seven hundred subjects underwent acceptable post-bronchodilator spirometry. The overall prevalence of GOLD COPD was 4.2% (men 5.7%, women 2.5%). The overall prevalence of COPD stage 1 or higher using the LLN was lower than estimates using the GOLD criteria (3.2%). The overall prevalence of GOLD stage 2 or higher COPD was 3.7%. Male sex, increasing age and smoking were significantly associated with COPD diagnosis. CONCLUSION: The overall prevalence of COPD in Saudi Arabia is 4.2%. Male, increasing age and smoking were the main risk factors for COPD.

The Saudi clinical practice guideline for the diagnosis of the first deep venous thrombosis of the lower extremity

The diagnosis of deep venous thrombosis (DVT) may be challenging due to the inaccuracy of clinical assessment and diversity of diagnostic tests. On one hand, missed diagnosis may result in life-threatening conditions. On the other hand, unnecessary treatment may lead to serious complications. As a result of an initiative of the Ministry of Health of the Kingdom of Saudi Arabia (KSA), an expert panel led by the Saudi Association for Venous Thrombo-Embolism (SAVTE; a subsidiary of the Saudi Thoracic Society) with the methodological support of the McMaster University Working Group, produced this clinical practice guideline to assist healthcare providers in evidence-based clinical decision-making for the diagnosis of a suspected first DVT of the lower extremity. Twenty-four questions were identified and corresponding recommendations were made following the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. These recommendations included assessing the clinical probability of DVT using Wells criteria before requesting any test and undergoing a sequential diagnostic evaluation, mainly using highly sensitive D-dimer by enzyme-linked immunosorbent assay (ELISA) and compression ultrasound. Although venography is the reference standard test for the diagnosis of DVT, its use was not recommended.(AU)

Prevalence of rhinitis symptoms among 16 to 18 years old adolescents in Saudi Arabia.

OBJECTIVE: The present study was designed to estimate the prevalence of rhinitis symptoms among secondary school students in Saudi Arabia METHODS: A cross-sectional study was conducted among children from secondary schools in the city of Riyadh. The study utilised the International Study of Asthma and Allergies in Children (ISAAC) questionnaire. RESULTS: Among the 3073 students (1504 boys and 1569 girls), the prevalence of life-time rhinitis, rhinitis in the past 12 months, and hay fever were 43.8%, 38.6% and 21.3%, respectively. There was a significant difference between boys and girls in the prevalence of life-time rhinitis (41% versus 46.5%, p = 0.02) and the prevalence of rhinitis in the past 12 months (35.1% versus 41.9%, p = 0.001). There was no significant difference between boys and girls in the prevalence of hay fever (22.5% versus 20.2%, p = 0.144). The prevalence of asthma symptoms among students with life-time rhinitis and hay fever were 35.4% and 39.9%, respectively. Asthma symptoms were strongly linked with life-time rhinitis (Odds Ratio [OR] = 2.5, p < 0.001) and hay fever (OR = 2.4, p value < 0.001). CONCLUSIONS: The prevalence of rhinitis symptoms is high among 16 to 18 years old adolescents in Saudi Arabia, and symptoms are more common in girls compared to boys. Rhinitis symptoms are also associated with a high frequency of asthma symptoms.

Interleukin 17A and F and asthma in Saudi Arabia: gene polymorphisms and protein levels.

BACKGROUND: Asthma is a multifactorial disorder, and both genetic and environmental factors contribute to its development. We investigated the possible association between asthma and 5 single-nucleotide polymorphisms (SNPs) in the interleukin 17 (IL17) gene--rs17880588 (G/A) and rs17878530 (C/T) in IL17A and rs763780 (T/C), rs11465553 (T/C), and rs2397084 (G/A) in IL17F--and compared levels of the proteins IL17A and IL17F in asthma patients with those of controls. PATIENTS AND METHODS: The study group included 100 asthma patients and 102 ethnically matched controls. Genotyping was performed on purified DNA using reverse transcriptase-polymerase chain reaction with specific primers and probes. Levels of IL17A and IL17F were measured in plasma using enzyme-linked immunosorbent assay. RESULTS: Genotyping showed that AG heterozygotes of rs17880588 in IL17A were significantly more common in the control group than among the asthma patients (P < .05); no significant associations were observed for any of the other SNPs examined. Levels of IL17A and IL17F were both higher in asthma patients (IL17A, 2.242 [0.099] vs 2.752 [0.287] pg/mL; IL17F, 236.01 [38.28] vs 700 [201.078] pg/mL). The difference was statistically significant for IL17F (P = .025, t test). Levels of IL17A and IL17F were positively and significantly correlated in the asthma patients CONCLUSION: Of all the SNPs analyzed, only rs17880588 showed a significant association with asthma in the Saudi population we studied. Levels of IL17A and IL17F were significantly upregulated in the asthma patients. The morphology of IL17F appeared to affect expression levels.

Progressive rise of Mycobacterium tuberculosis resistance to rifampicin and streptomycin in Riyadh, Saudi Arabia.

OBJECTIVE: The aim of this study was to investigate, for the first time, the factors associated with resistance to antituberculous drugs in Saudi Arabia, and to follow the long-term trends in drug resistance. METHODOLOGY: A retrospective study of patients with positive Mycobacterium tuberculosis recorded at the Riyadh Tuberculosis Center in 1990 was undertaken. The resistance figures from the same centre for the period July 1996 to June 1997 were reviewed for comparison. RESULTS: Resistance was significantly higher in those previously treated (71%) than in those who denied previous treatment (34%). There was a trend towards association of resistance with cavitatory, multilobar, and acid fast bacilli-positive cases. Nationality (Saudis, Yemenis, others) had no significant effect on resistance. The Riyadh Region now has the same high prevalence of rifampicin resistance as previously reported in the Western Region of the Kingdom. The figures on resistance for the years 1986-88, 1990, and 1996-97 were: isoniazid 19.5/13.8/11.1%, rifampicin 10/20.7/24.6%, streptomycin 5/22/27.4%, ethambutol 3.7/3.9/1.8%, respectively. The reduction in isoniazid and ethambutol resistance coincided with a rise in resistance to rifampicin and streptomycin. We speculate that this resulted from the fact that isoniazid and ethambutol are restricted only to the treatment of tuberculosis and cannot, by law, be dispensed by general practitioners or private pharmacies. Rifampicin and streptomycin, however, are widely used for brucellosis; an endemic disease in Saudi Arabia where up to 12 weeks of rifampicin therapy is recommended. CONCLUSIONS: There has been a significant increase in rifampicin and streptomycin resistance in Saudi Arabia over the last 10 years. Possible causes include poor compliance and wide use of these two drugs for non-tuberculosis conditions. These findings could jeopardize the benefits of the directly observed therapy short course policy which is being implemented in Saudi Arabia. Consideration should be given to prohibiting the routine use of rifampicin for the treatment of brucellosis.

Predictors of radiological sequelae of pulmonary tuberculosis.

PURPOSE: In patients with pulmonary tuberculosis, clinical factors that are associated with poor radiological outcome have not been adequately addressed in the medical literature. The aim of this study was to explore some of these factors in patients admitted to a large chest hospital in Saudi Arabia with pulmonary tuberculosis. MATERIAL AND METHODS: Chest radiographs of 1,080 patients with pulmonary tuberculosis were reviewed. Post-treatment residual changes were classified from 1 to 5 according to the severity of these changes. Data analysis was done by tabulating these classes against different variables that were likely to influence the final radiological appearance at the end of the treatment period. RESULTS: Near-complete or complete clearance of chest radiography (Class 1) was seen in 43.5% of patients <20 years old compared to 30.3% in patients > 40 years old (p < 0.05). The latter group also had significantly higher rate of pleural thickening (9.4% vs. 3.6%), higher rate of fibronodular densities (24.9% vs. 19.5%) and higher rate of persistent cavitation (18.3% vs. 11.9%). Females had a significantly lower rate of chest radiography clearance (30.5%)) than males (41.4%). Patients with a duration of respiratory symptoms of <4 weeks had 45.2% Class 1 radiography compared to 24.6% for those with longer duration of symptoms (> 8 weeks). Chest radiography clearance was more frequent (51.6%)) in patients with good compliance with drug therapy compared to those with poor compliance (18.8%). Persistent cavitation (Class 5) was seen in 30.4% of cases with a past history of tuberculosis and in only 14% of cases with no such history. CONCLUSION: Old age, female gender, long duration of symptoms (delayed diagnosis), poor compliance with treatment and positive history of tuberculosis were associated with poor radiological outcome.

High rate of non-compliance with anti-tuberculosis treatment despite a retrieval system: a call for implementation of directly observed therapy in Saudi Arabia.

SETTING: Taif Chest Hospital, Taif, Saudi Arabia. OBJECTIVES: Non-compliance with anti-tuberculosis drug therapy is recognised as a major cause of treatment failure, drug resistance and relapse. In Saudi Arabia, the problem of non-compliance is frequent and has serious implications which need urgent attention from the health-care authority. The objectives of this study were to define factors that affect compliance rate and to determine the appropriate methods to modify these factors. DESIGN: We designed and tested a retrieval system to improve patient return for follow-up and drug collection after an initial hospital admission period in a large chest hospital in the western region of the country. RESULTS: Of 628 patients, 358 (57%) did not attend the first out-patient clinic visit. The retrieval system was successful in bringing back only 83 patients, reducing the default rate by only 13.2%. Various factors that may affect compliance were analysed in the remaining 275 (43.8%) non-compliant patients. CONCLUSION: Because many of these factors are difficult to change, we strongly support implementation of the WHO-recommended directly observed treatment (DOT) strategy in Saudi Arabia and other countries facing similar problems with tuberculosis control.

The outcome of tuberculosis treatment after implementation of the national tuberculosis control program in Saudi Arabia.

BACKGROUND: Tuberculosis is an endemic disease in Saudi Arabia. Efforts to control this disease started in 1992 with the establishment of a National Tuberculosis Control Committee. Field application of a national tuberculosis control program (NTCP) was implemented in Riyadh in 1996 by the Ministry of Health, according to the guidelines of the World Health Organization (WHO). This study was aimed at evaluating the outcome of tuberculosis treatment before and after the implementation of this program. PATIENTS AND METHODS: All active tuberculosis cases admitted and treated in the Sahary Chest Hospital, Riyadh, were studied. The outcome of treatment was evaluated, and a comparison was made between 1995 (before the implementation of the NTCP) and the years 1996-1998 (after implementation). RESULTS: The total number of tuberculosis cases increased from 504 in 1995 to 726 (44%) in 1998. Cure rate increased from 24.4% to 36.2%, and the default rate decreased from 15% to only 1.2% during the same period. However, there was no change in the rate of completion of treatment, the rate of treatment failures, relapse or deaths. CONCLUSION: Although the cure rate slightly improved and the default rate decreased, the overall outcome of the implementation of the national tuberculosis control program was not satisfactory. A recommendation for speedy application of directly observed therapy strategy (DOTS) is made to improve the control of tuberculosis in Saudi Arabia.

Clinical profile of sleep apnea syndrome. A study at a university hospital.

OBJECTIVES: To review a series of patients with sleep apnea syndrome, to promote more awareness and alert local health professionals to early diagnosis and treatment. METHODS: We studied, prospectively, 48 consecutive patients who were managed at the university hospital from 1992 to 1996. RESULTS: The male:female ratio was 1.4:1. The mean interval between onset of symptoms and the diagnosis was 5.5 years (range 0.25 to 30). In over half of the patients the diagnosis was not suspected upon referral. The mean body mass index was 42.8 kg/m2, (range 25 to 76). Daytime hypoxemia was present in 28 patients (58%), while 26 (54%) had Pa CO2 > 45 mmHg, mainly as a result of obesity-hypoventilation syndrome. Significant proportions had systemic and pulmonary hypertension (60% and 23%), and 32% had ischemic heart disease. All patients, but one, tolerated continuous positive airway pressure, but cost of the equipment led some to prefer surgical treatment that is offered free. CONCLUSION: This series shows a bias towards female sex and frequent association with obesity-hypoventilation syndrome. In many cases the diagnosis was not suspected suggesting poor recognition and awareness of sleep apnea syndrome. Monitoring pulse oximetry during sleep was helpful in the diagnosis and titration of continuous positive airway pressure. Ways of providing continuous positive airway pressure under the health system need to be studied.

Massive pulmonary hemorrhage in a Saudi female with primary antiphospholipid syndrome.

The antiphospholipid syndrome is characterized by the presence of antiphospholipid antibodies and the association of protean clinical manifestations as a result of both venous and arterial thrombosis. Because diffuse alveolar hemorrhage leading to acute respiratory failure is a rather unusual complication of antiphospholipid antibodies, this diagnosis may be overlooked or its manifestations are attributed to another disease. Presented here is a young Saudi female with primary antiphospholipid syndrome who recovered after a stormy clinical course of acute respiratory failure in the intensive care unit.

Improved sensitivity for detection of tuberculosis cases by a modified Anda-TB ELISA test.

Tuberculosis is still a major health problem in most developing countries and its incidence is rising in many industrial countries. The diagnosis of tuberculosis depends primarily on identification of mycobacteria and on clinicoradiological evidence of the disease. Compared to other diagnostic methods, serological tests are faster and do not necessarily require samples that contain the tubercle bacilli. We have evaluated a modified version of a commercially available enzyme immunoassay test to detect the presence of circulating anti-mycobacterial IgG and IgM antibodies in tuberculosis patients. The sensitivity and the specificity of the test reaches 87% and 95% respectively. In conclusion, the modified Anda-TB enzyme immunoassay test offers a good and reliable test for diagnosis of tuberculosis in suspected cases of active pulmonary tuberculosis.

Evaluation of the teratogenic potential of pyrazinamide in Wistar rats.

We have tested Pyrazinamide (PZA), an essential component of modern short-course tuberculosis treatment regimen, for teratogenicity using Wistar rats. The drug was given by oral intubation from 6-15 days of gestation, at doses of 0, 25, 100 and 500 mg/kg body weight per day. Reduction in body weight and food consumption were observed in the treated dams. On day 20 of gestation, all the dams were killed by cervical dislocation and signs of maternal toxicity, reproductive indices and fetal measurements were recorded. Dams given doses of 100 and 500 mg/kg had significantly higher incidence of reabsorbed fetuses, reduced litter size, and impaired neonatal growth than those given no PZA or only 25 mg/kg dose. External visceral and skeletal examination of all fetuses of PZA-treated dams showed several types of variations which were neither dose related nor having a consistent pattern. However, these variations occurred mostly in the dams treated with the dose of 500 mg/kg. In conclusion, these data show that in Wistar rats, only high doses of PZA (100 and 500 mg/kg) produced fetotoxicity. No evidence of teratogenic effect of the drug was observed.

Overlooked inhaled foreign bodies: late sequelae and the likelihood of recovery.

The present paper describes eight patients (two teenagers and six adults) who had chronic symptoms (haemoptysis, cough, recurrent pneumonia) caused by foreign body (FB) inhalation which went undetected for 3 months to 25 yr. None of the patients had the usual predisposing conditions like mental retardation, seizures or brain tumour. The diagnosis of FB was made by radiography in one patient only. Computerized tomography visualized one FB (a beef bone), and bronchoscopy identified FB in another two patients. The remaining four cases were diagnosed at thoracotomy. Removal of FB was curative in three of five cases who required surgical resection for irreversible bronchiectatic changes. The severity of pulmonary changes correlated with duration of symptoms. It is concluded that chronic, unexplained respiratory symptoms should warrant further investigation to exclude FB despite negative history and normal chest radiography. Finding of granulation tissue or cicatricial stenosis of the bronchus could be the only clue to the presence of a FB. Early diagnosis would avoid irreversible parenchymal changes which necessitate lung resection.

Surgery for unilateral bronchiectasis: results and prognostic factors.

SETTING: King Khalid University Hospital referral centre for thoracic surgery, Riyadh, Saudi Arabia. OBJECTIVE: To assess the results of surgery and factors influencing its outcome in patients with unilateral bronchiectasis. DESIGN: A retrospective analysis of 40 patients with unilateral bronchiectasis who were operated upon consecutively at King Khalid Hospital, between July 1987 and May 1993. RESULTS: Left-sided disease was seen in 60% (n = 24) and right-sided in 40% (n = 16) of the patients. The entire lung was involved in 30% of cases (n = 12). Of these, the left lung was totally involved in 22.5% (n = 9) and the right in 7.5% (n = 3). A lobectomy was performed on 21 patients, basal segmentectomy with preservation of apical segment on 7, and pneumonectomy on 12. There was no operative mortality in this series. Six patients (15%) developed postoperative complications, bleeding (n = 4) and prolonged air leak (n = 2). During an average follow-up period of 30.7 months (+/- 15.4 months), 29 patients (72.5%) were cured and the remaining 11 (27.5%) improved. No patients with Pseudomonas aeruginosa infection (n = 3) or obstructive airway disease (n = 5) were cured (P = 0.02 and P = 0.002 respectively). CONCLUSION: Curative resection for selected patients with unilateral bronchiectasis can be performed safely with good results and low morbidity. Pseudomonas aeruginosa infection and obstructive airway disease have an adverse effect on postoperative cure.

Does the protective effect of neonatal BCG correlate with vaccine-induced tuberculin reaction?

A case-control study was conducted in Saudi Arabia, where the same strain of BCG has been used and surveys had shown that up to 88% of vaccinated children remain tuberculin negative. Active cases were obtained by surveying the seven tuberculosis centers in 1 yr. Control subjects were obtained from a nationwide survey of normal individuals. Vaccination in both groups was ascertained by history and BCG scar. Relative risk of contracting active tuberculosis in the vaccinated versus unvaccinated and protection was calculated. Protection was as follows: age group 5 to 14 yr, 82% (55 to 93%); age group 15 to 24 yr, 67% (55 to 77%); and age group 25 to 34 yr, 20% (-6 to 37%). We document the uninterrupted record of protection by BCG administered in the neonatal period and discuss the significance of vaccination timing. We concur with other studies that protection lapsed after about 20 yr. More importantly, this is the first large study that documents a lack of tuberculin sensitivity despite protection. This challenges the view that sensitization is essential for protection and supports the "two-pathway" theory that BCG vaccination could trigger either protective (Lister type) or antagonistic (tuberculin or Koch type) reactions and that the most protective vaccines would have little tuberculin-sensitizing effect because the two pathways are competitive.

Effect of moderately high altitude on the pattern of lung disease.

In high altitude areas, inspired atmosphere oxygen decrease proportionally to the vertical distance from sea level. Population in these areas some adaptive mechanisms to cope with the relatively hypoxic environment. This study compares populations who live in highland areas (2500 meters above sea level) with those in lowland areas (close to sea level). No differences were observed in the prevalence or mortality rate of respiratory diseases between these two groups. It is concluded that even if adaptive mechanisms can be observed in dwellers of moderately high altitude (<3000 m above sea level), such altitude does not adversely affect the pattern of respiratory disease in these populations. However, partial pressure of oxygen (PaO2) tends to be lower in individuals of high altitude areas, leading to marked oxygen desaturation when such individuals encounter a significant respiratory illness. Physicians are advised to introduce early and effective therapeutic measures before such deterioration occurs.

Overwhelming respiratory failure associated with Legionella pneumophila.

Four patients were admitted to the medical intensive care unit at King Khalid University Hospital (KKUH) with overwhelming respiratory failure. Extensive investigations revealed serological evidence of Legionella infection. Three patients required intubation and mechanical ventilation. All patients received erythromycin; rifampin was added to two patients. Two patients survived and two patients died. We report, for the first time in Saudi Arabia, four cases of Legionella pneumophila with severe respiratory failure.

Nationwide community survey of tuberculosis epidemiology in Saudi Arabia.

In the first nationwide community-based survey of the epidemiology of tuberculosis in Saudi Arabia, 7721 subjects were screened in the 5 provinces (using an equal proportional allocation formula) for 2 parameters: (1) prevalence of positive Mantoux test in non BCG vaccinated subjects; (2) prevalence of bacillary cases on sputum culture. The prevalence of positive Mantoux reaction in children aged 5-14 years was 6% +/- 1.8; higher in urban areas (10%), and lower in rural areas (2%), thus classifying Saudi Arabia among the middle prevalence countries. These relatively good results (by Third World standards) could reflect the rise of the standard of living and wide availability of free treatment for active cases with a lowered risk of infection in the community. This view is supported by the fact that in our survey, only one subject grew Mycobacterium tuberculosis in the sputum. However, there were foci of high prevalence of Mantoux reaction in the urban communities in the Western province (20% +/- 8.7 urban; 1% +/- 1.9 rural). The problem may be caused by the fact that the province receives every year over a million pilgrims, some of whom are known to settle illegally and escape the usual screening for tuberculosis imposed on foreign labourers. In conclusion, even in the absence of an enforceable national programme for the eradication of tuberculosis, the economic standard and wide availability of free treatment for active cases has resulted in relatively low rates of prevalence of tuberculin sensitivity in children. The foci of high prevalence in the Western Province require special screening arrangements.