Medical thoracoscopy for exudative pleural effusion: an eight-year experience from a country with a young population.

BACKGROUND: With the exception of areas with high prevalence of tuberculosis, medical thoracoscopy is becoming the diagnostic modality of choice for exudative pleural effusions. The aims of this study were to determine the diagnostic yield and safety of medical thoracoscopy for exudative pleural effusions and ascertain the etiology of such effusions in Qatar. METHODS: This is a retrospective-descriptive study of 407 patients who underwent diagnostic medical thoracoscopy for exudative pleural effusions from January, 2008 till December, 2015 at the only tertiary referral center performing this procedure in Qatar. RESULTS: Tuberculosis was the most common etiology of exudative pleural effusions in Qatar accounting for 84.5% of all causes. Around 85% of patients were young males (mean age of 33 ± 12.1 years). The diagnostic yield of medical thoracoscopy for tuberculous pleural effusion was 91.4%. Malignant pleural effusions accounted for 5.2% of cases. Minor bleeding occurred in 1.2% of cases with no procedure-related mortality observed. CONCLUSION: Medical thoracoscopy is a very safe procedure. Tuberculous pleuritis is by far the most common etiology of exudative pleural effusions in Qatar. Closed needle biopsy is a worth consideration as an initial safe, easy and low-cost diagnostic modality for exudative pleural effusions in this country.

Characterisation of winter respiratory viral infections in patients with asthma and COPD in Qatar.

Respiratory viruses in patients with chronic obstructive pulmonary disease (COPD) or asthma have not been characterised in Qatar. This study aimed to identify the most common viral strains responsible for respiratory tract infections in asthma/COPD patients (without exacerbations) in Qatar during the winter season (2008-2009). Nasal swabs from patients with asthma/COPD and respiratory symptoms were evaluated for 15 common viruses. 200 adult patients (190 with asthma and 10 with COPD) were enrolled. Viral infections were present in 36 out of 200 patients (18 %). Cough and wheezing were the most common symptoms. Rhinovirus was the most common causative agent, followed by coronaviruses. Our findings confirm previous reports of rhinovirus prevalence in respiratory tract infections in asthma/COPD. A countrywide survey to confirm our findings is warranted.

The correlation between middle schoolchildren allergic symptoms and airborne particle season: A cross-sectional study.

ABSTRACT: Limited studies correlate allergic symptoms and associated outdoor biological particle exposure among schoolchildren globally.This study aimed to investigate the relationship between the seasonality of symptoms of allergic diseases among middle schoolchildren and the annual variation of airborne pollen and fungal spore in a hot and humid geographical region (Qatar).During November 2017 to January 2018, a self-reported study of middle schoolchildren living in the Doha capital city of Qatar was conducted, and data gathered were evaluated in relation to the collected monthly pollen and fungal spores. Participants' data were collected by conducting a survey based on a modified questionnaire adopted from the International Study of Asthma and Allergy in Childhood (ISAAC). The airborne pollen and fungal spore in Doha's atmosphere were extracted from the Doha aerobiology project (2017-2020).Among the 1000 distributed questionnaires, 100 were excluded due to significant missing data and 644 middle schoolchildren living in Doha city responded and were included in the final analysis. The symptoms of allergic rhinitis (AR) pattern among the responders with positive symptoms were strongly linked with the higher airborne fungal spore incidence during the month of November. Out of 331 students with positive symptoms, the prevalence of AR, lifetime wheeze, and eczema was 62.8%, 28.1%, and 26.6%, respectively. Asthma was significantly higher in Qatari (39.8%) compared to non-Qatari (26.7%) middle schoolchildren (P = .02).Outdoor aeroallergen may be a contributing factor in addition to other environmental and genetic predisposing factors for childhood atopic diseases in the prevalence rate of allergic symptoms among middle schoolchildren in the peninsula of Qatar.

Aerobiological monitoring in a desert type ecosystem: Two sampling stations of two cities (2017-2020) in Qatar.

BACKGROUND: The increasing number of aerobiological stations empower comparative studies to determine the relationship between pollen concentrations in different localities and the appropriate distance, which should be established between sampling stations. In Qatar, this is basically the first aerobiological study for a continuous monitoring interval. OBJECTIVES: The study aimed to assess the abundance and seasonality of the most prevalent pollen types, plus identify potential differences between two sites within the country. METHODS: Airborne pollen data were collected during 2017-2020 by using Hirst-type volumetric samplers in Doha capital city and Al Khor city in Qatar, placed 50 km apart. RESULTS: Higher total pollen indexes were recorded in the Al Khor station (2931 pollen * day/m3) compared to the Doha station (1618 pollen * day/m3). Comparing the pollen spectrum between the sampling stations revealed that ten pollen types were found in common. Amaranthaceae and Poaceae airborne pollen constituted 73.5% and 70.9% of the total amount of pollen detected at the samplers of Al Khor station and Doha station. In both sampling sites, a very pronounced seasonality was shown; August-October appeared as the period with the most intense incidence of atmospheric herbaceous pollen, with 71% and 51% of the annual total counts in Al Khor and Doha stations, respectively. August (Al Khor, 21%; Doha, 9%), September (Al Khor, 33%; Doha, 26%), October (Al Khor, 17%; Doha, 16%) were the months in which the herbs pollen concentrations were highest. Significant statistical differences between the two stations were observed in specific pollen types with local distribution in each trap's vicinity. CONCLUSIONS: Comparison of data obtained by the two samplers running at a distance of 50 Km indicated that potential inter-site differences could be attributed to the vegetation surrounding the city having a decisive influence on data collected.

The association between airborne pollen monitoring and sensitization in the hot desert climate.

BACKGROUND: Pollen is a major cause of allergic respiratory diseases. In Qatar, data on the presence and prevalence of allergenic airborne types of pollen is quite limited. METHODS: The study aimed to determine and correlate the most frequently implicated airborne pollen detected by aerobiological monitoring samplers in respiratory allergy symptoms. An aerobiological survey was started on May 8, 2017. Airborne pollen was collected using two Hirst type seven-day recorder volumetric traps. Skin prick test in patients attending allergy clinics in Doha using commercial extracts was conducted. RESULTS: Twenty-five pollen types representing the native, as well as the introduced plants, with a relatively low daily mean concentration were observed from May 2017 to May 2019. The highest pollen concentrations were reached by Amaranthaceae (58.9%), followed by Poaceae (21.7%). SPT revealed a comparatively higher degree of sensitization to pollen. Among 940 patients, 204 were sensitized to pollen (54% female) with 135 (66.2%) and 114 (55.8%) to Amaranthaceae and Poaceae, respectively. Some patients had polysensitization. There was a statistically significant association between Amaranthaceae, and asthma (r = 0.169, P = 0.016) and allergic rhinitis (r = 0.177, P = 0.012). CONCLUSIONS: This is the first study to monitor airborne pollen in the state of Qatar. The main pollen detected were Amaranthaceae and Poaceae. Pollen may represent a possible exacerbating factor in adult patients with allergic diseases such as asthma and allergic rhinitis.

Diagnostic value of bronchoalveolar lavage in the subset of patients with negative sputum/smear and mycobacterial culture and a suspicion of pulmonary tuberculosis.

BACKGROUND: The diagnostic value of bronchoalveolar lavage in patients with negative sputum/smear for tuberculous bacilli has been well studied. However, its value in the subset of patients with both negative sputum/smear and culture is seldom reported. METHODS: A retrospective study of patients referred for diagnostic bronchoscopy for the suspicion of pulmonary tuberculosis during the period from April 1st, 2015 to March 30th, 2016, and who had negative sputum/smear and culture for tuberculous bacilli. RESULTS: One hundred and ninety patients fulfilled the inclusion criteria. Bronchoalveolar lavage detected further 61/190 (32.1%) pulmonary tuberculosis cases. Bronchoalveolar lavage mycobacterial culture and polymerase chain reaction (positive in 60/190 (31.6%) and 58/190 (30.5%) of patients respectively) provided the highest diagnostic yield, whereas direct smear provided the lowest yield. Bronchoalveolar lavage had a sensitivity of 89.7%, a specificity of 100%, a positive predictive value of 100%, a negative predictive value of 94.6%, and a test accuracy of 96.3% in suspected pulmonary tuberculosis cases with negative sputum/smear and culture. Positive bronchoalveolar lavage yield for tuberculosis was significantly associated with a positive QuantiFERON-TB Gold In-Tube test, positive purified protein derivative skin test, radiological evidence of upper zone abnormality and patient's origin being from the Indian subcontinent. CONCLUSION: Bronchoalveolar lavage should be pursued as a useful diagnostic tool for suspected pulmonary tuberculosis cases when sputum/smear and culture are negative. Its value is higher in the subset of patients with positive QuantiFERON-TB Gold In-Tube test, positive purified protein derivative skin test, upper zone abnormality on radiograph or being from the Indian subcontinent.

The pattern of indoor and outdoor respiratory allergens in asthmatic adult patients in a humid and desert newly developed country.

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 State of Qatar. OBJECTIVE: To characterize the most frequent indoor and outdoor respiratory allergens involved in bronchial asthma and allergic rhinitis in the State of Qatar. DESIGN: A hospital-based prospective study conducted. SETTING: Allergy Laboratory at the Hamad General Hospital and Hamad Medical Corporation, Doha, State of Qatar. PATIENTS: Adult patients over 12 years of age diagnosed with bronchial asthma and/or allergic rhinitis who were referred for allergy skin pick test. 1106 adult patients recruited with respiratory diseases of suspected allergic origin who attended Allergy Clinic at the Hamad General Hospital, during three years from January 2001 to April 2003. Total of 1106 whom 607 were females (54.9%) and 499 were males (45.1%) and their mean was age 30 years (12-48). METHODS: Skin Prick Test [SPT] was performed on 1106 patients for common allergens whom The blood sample was taken for measuring specific IgE concentration. RESULTS: There were 1106 patients studied and 569 patients (51.4%) had positive skin prick test. All patients expressed clinical allergy, 464 patients (52%) had asthma and rhinitis, 286 patients (32%) had rhinitis alone and 137 patients (15%) had asthma alone. The population sample had a higher prevalence of diagnosed asthma among females (32.7%) than in males (29.8%) and also skin conditions such as eczema, pruritus, and urticaria higher in females (9.1%%) than males (7.0%). Similarly, males had higher prevalence of allergic rhinitis (86.0%) than in females. There were 318 (55.9%) patients whose asthma developed before they were 10 years old. The percentage of asthmatic patients with a positive family history of asthma was 44%. The most common allergens detected in order of frequency were Dermatophagoides Pteronyssimus (Der p l) in 248 patients (41.6%), Dermatophagoides Farinae (Der f l) in 220 patients (36.9%), Cockroach allergen (Bla g l) in 192 patients (32.2%). The study showed that females are more exposed to pollen, grasses and tress, but males are mostly exposed to mites and insects. Furthermore, Molds and Yeast were common among males. CONCLUSION: In conclusion, the frequency of indoor and outdoor allergens in state of Qatar, based on skin prick test study showed the dominance of house dust mites, pollen, grasses which are more or less same to other countries with similar and even with different climate. Reduced exposure to these agents will help control raising severity of these disease.

Indications, diagnostic yields and complications of transbronchial biopsy over 5 years in the State of Qatar.

OBJECTIVES: To review the indications, diagnostic yields and complications of transbronchial biopsy (TBB) in a tertiary hospital in the State of Qatar. METHODS: A retrospective review of our records revealed 1006 adult flexible fibre optic bronchoscopies (FFB) at Hamad General Hospital, State of Qatar between January 1999 and December 2003. A total of 85 (8.4%) TBB were performed, but complete data were available for 71/85 (83.5%), which were reviewed for indications, diagnostic yields and complications. RESULTS: Adequate samples were obtained in 58/71 TBBs (81.7%), while 13/71 TBBs (18.3%) yielded bronchial mucosa. The main indications in 16/71 (22.5%) TBBs for radiographic localized pulmonary disease were to rule out tuberculosis (TB) in 13 cases, and malignancy in 3 cases. Tuberculosis was verified in 3 (23%) of the 13 cases with localized disease. Fifty-five out of 71 (77.5%) TBBs were performed for radiographic diffuse pulmonary disease: 16/55 (29%) for miliary shadows, while 39/55 (70.9%) were carried out for reticular/reticulonodular infiltrates. Histopathology showed granulomatous lesions consistent with TB in 10/16 (62.5%) cases of miliary shadow. In the other pattern of diffuse disease, the histopathological diagnosis were obtained in 25/39 (64%) cases. It showed non-specific pulmonary fibrosis in 13 cases, sarcoidosis in 4 cases, connective tissue disease associated interstitial fibrosis in 4 cases, bronchiolitis obliterans organizing pneumonia (BOOP) in one case, eosinophilic pneumonia in one case, amiodarone toxicity in one case and lymphangitis carcinomatosis in one case. The main complications were minor bleeding <50 cc in 17 cases (23.9%), pneumothorax in 7 cases (9.8%)) and one case had sepsis. CONCLUSION: Our experience substantiates previous reports of the value and safety of transbronchial biopsy in the rapid diagnosis of smear-negative miliary TB. In diffuse lung diseases of a non-infectious nature, other than sarcoidosis, lymphangitis carcinomatosis and few other conditions, a pathological diagnosis are much less likely to be reliably made on small pieces of tissue such as those provided by TBB.