Yavuz Selim Demirel
Ankara University
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Featured researches published by Yavuz Selim Demirel.
Journal of Asthma | 1999
Sevim Bavbek; Gülfem Çelik; Dane Ediger; Dilgad Mungan; Yavuz Selim Demirel; Zeynep Misirligil
Intolerance or idiosyncrasy to acetylsalicylic acid (ASA) and other nonsteroidal anti-inflammatory drugs (NSAIDs) is a crucial problem because these drugs are frequently used in medical treatment. In this study, we tested whether nimesulide, a selective cyclooxygenase-2 (COX-2) inhibitor, might be a valid alternative for patients with histories of adverse reaction to ASA or NSAIDs. A single-blind, placebo-controlled oral challenge procedure was applied to 60 adult patients (19 male, 41 female; with a mean age of 40.31 +/- 10.44 years, range 20-68 years) with a reliable history of ASA/NSAIDs-intolerance. According to history, the clinical presentations of intolerance were urticaria/angioedema in 32 patients, anaphylactoid reaction in 2 patients, respiratory reaction in 19 patients, and respiratory and cutaneous reaction in 7 patients. Atopy was confirmed by means of skin prick test with inhalant allergens. Oral challenge protocol was started with 25 mg of nimesulide and the remaining 75 mg was given 1 hr later. During the challenge procedure, blood pressure, pulse, nasoocular, pulmonary, and cutaneous symptoms were monitored. Of the 60 patients tested, 55 (91.7%) tolerated the drug with no adverse reaction. Only five (8.3%) patients demonstrated a positive response to oral challenge. The clinical presentations of intolerance to nimesulide were urticaria/angioedema in three patients, mild rhinitis in one patient, and mild dyspnea in one patient. The atopy prevalence was higher, with a ratio of 41.7%, in patients with ASA/NSAIDs intolerance than that of the healthy adult population in Turkey (p < 0.05). We believe that nimesulide can be used as an alternative drug for patients with ASA/NSAIDs intolerance.
Journal of Asthma | 1999
Gülfem Çelik; Dilaad Mungan; Sevim Bavbek; Betül Ayşe Sin; Dane Ediger; Yavuz Selim Demirel; Zeynep Misirligil
To assess the prevalence of allergic diseases and atopy in adults, a two-step population-based epidemiological study was undertaken in Ankara, the capital city of Turkey. In step 1, a screening questionnaire adapted from the European Community Respiratory Health Survey (ECRHS) was applied in a cross-sectional manner. In step 2, a nested case-controlled design study was conducted and subjects were evaluated in the clinical setting for history, physical examination, skin prick tests (SPTs), and serum total IgE and phadiotop measurements. According to the results, self-reported current asthma prevalence in step 1 was lower compared with that in step 2 (3% vs. 7%, p < 0.05). The prevalences of food and drug allergy were 6.2% and 3.9%, respectively, in step 1, but were not demonstrated in any of the subjects in step 2. The overall prevalence of atopy was 25% after step 2 evaluation. In conclusion, allergic disorders are not uncommon in our adult population; however, sole application of a screening questionnaire appeared to be ineffective in revealing the accurate figures of asthma, and food or drug allergy.
Allergy | 1998
Dilşad Mungan; Gülfem Çelik; Betül Ayşe Sin; Sevim Bavbek; Yavuz Selim Demirel; Zeynep Misirligil
Exposure to cockroach has been reported to cause asthma in many parts of the world. Although house‐dust‐mite is known to be the most important indoor allergen in Turkey, there are few data on the prevalence of allergy t o cockroaches. Therefore, we evaluated the prevalence of cockroach sensitivity in asthmatic TUrkish patients to see whether it is also an important source of asthma in addition to house‐dust mites. A total of 206 patients demonstrating the characteristic features of asthma were included in the study. Sixty‐three percent of the patients were considered atopic, and 37% were found to be nonatopic by skin prick tests. Mite allergens were the most common cause of indoor allergy (50%), while cockroach sensitivity was detected in 25.7% of all the asthmatics. Among all cockroach‐sensitive patients, 70% were also positive for mites. A female predominance was observed in cockroach‐sensitive patients, as 44% of atopic women and 34% of atopic men had positive skin tests with cockroach allergen. The average duration of asthma was 7.1+5.6 years in cockroach‐sensitive asthmatics, and there was no difference between groups in average duration of asthma (P>0.05). Mild, moderate, and severe asthmatics constituted 73.6%, 20.7%. and 5.7% of the cockroach‐sensitive patients, respectively. These data indicate that cockroach is also an important source of domestic infestation n i Tlirkey. Thus, it seems reasonable to suggest the need for cockroach allergen in the routine battery of inhalant skin tests in this geographic location. However, possible cross‐reactivity with mites has to be taken into consideration during the clinical evaluation of subjects with cockroach sensitivity, especially in our patient population with such high rates of house‐dust‐mite allergy.
International Archives of Allergy and Immunology | 2011
Ozlem Goksel; Ömür Aydın; Çetin Atasoy; Serdar Akyar; Yavuz Selim Demirel; Zeynep Misirligil; Sevim Bavbek
Background: Hypersensitivity to contrast media (CMs) may be common and serious. Aim: To evaluate the prevalence of CM hypersensitivity, risk factors associated with it and the role of skin testing in its diagnosis. Methods: A structured questionnaire was administered to patients who underwent computed tomography during a 1-year period. Skin tests with CMs, including skin prick tests (SPTs), intradermal tests (IDTs) and patch tests (PTs), were conducted on CM reactors (n = 24). Volunteers who tolerated CM exposure or had never been exposed to any CMs served as controls (n = 37). Results: A total of 1,131 patients (630 females and 501 males; mean age 55 ± 14.2 years) were enrolled in the study. The prevalence of historical and current CM reactors was 33/1,131 (2.92%) and 8/1,105 (0.72%), respectively. The skin was the most affected site, with mild to moderate reactions. Female gender, a history of doctor-diagnosed asthma, drug allergy, food allergy and psychiatric diseases were significant risk factors. The sensitivities of SPTs and early readings of IDTs in the diagnosis of immediate reactions were 0 and 20%, respectively, and the specificities were 94.6 and 91.4%, respectively. For early readings of IDTs, the positive predictive value (PPV) and negative predictive value (NPV) were 40 and 80%, respectively. For nonimmediate reactions, the sensitivities of delayed readings of IDTs and PTs were 14.3 and 25%, respectively; specificity was 100% for both tests. The PPV was 100% for both of these tests, and the NPVs were 85.4 and 82.4%, respectively. Conclusions: Our findings are comparable with the incidence, profile and risk factors associated with CM hypersensitivity reported previously. Skin testing with CMs has a high specificity, but its role in diagnosis is limited due to low sensitivity.
Annals of Allergy Asthma & Immunology | 2000
Sevim Bavbek; Gülfem Çelik; Dane Ediger; Dilşad Mungan; Betül Ayşe Sin; Yavuz Selim Demirel; Zeynep Misirligil
BACKGROUND The prevalence of asthma of varying severity and associated risk factors are unknown in Turkey. OBJECTIVE The study investigated the distribution of asthma severity, the factors having roles in asthma severity, and the relationship between serum eosinophil cationic protein (ECP) levels and disease severity. METHODS Three hundred patients with asthma (73 male, 227 female) were enrolled in the study. The patients were surveyed for their smoking habits, educational levels, household incomes, asthma duration, occupations, and accompanying diseases. ECP levels were also determined in certain patients representing different disease severities (n: 76) and in a control group (n: 9). RESULTS Patients were classified as mild intermittent (n: 14, 5%), mild persistent (n: 220, 73%), moderate (n: 44, 15%), and severe asthma (n: 22, 7%). Cigarette consumption and educational status were similar in all groups. A longer duration of disease and an older population predominated in patients with moderate and severe asthma. Analgesic sensitivity was seen in 7%, 10%, 6%, and 31% of mild intermittent, mild persistent, moderate and severe asthma patients, respectively, with the highest ratio in severe asthma (P < .05). Nasal polyps were significantly higher in severe asthmatics. Atopy was diagnosed in 85%, 57%, 56% and 10% of mild intermittent, mild persistent, moderate and severe asthma patients, respectively. ECP levels were significantly higher in moderate and severe asthma patients. CONCLUSIONS Mild asthma was the most common clinical presentation and was associated with atopy. The factors associated with severe asthma included prolonged asthma duration, advanced age, nonatopy, analgesic intolerance and nasal polyps. ECP levels also reflected disease severity.
Allergy | 1996
A. F. Kalpaklioglu; A. G. Ferizli; Zeynep Misirligil; Yavuz Selim Demirel; L. Gürbüz
Several observations have indicated that house‐dust mites (HDM) play an important role in allergic diseases. Thus, the primary form of treatment should aim at reducing exposure to HDM for these patients. Allergenavoidance measures in homes have been demonstrated to be beneficial in decreasing the risk of sensitization, severity of symptoms, bronchial reactivity, and basophil sensitivity. Various chemical methods, as well as physical measures, have been tried to eliminate mite allergens from house dust. However, none have gained wide acceptance because of the lack of effectiveness and safety, and the high cost. It is clear that new approaches are required for effective long‐term control of HDM allergens. This study compared the acaricidal activities of phenyl salicylate. tea leaf extract (high tannic acid content), and essential oils (eucalyptus and laurel) with that of benzyl benzoate. The contact, short‐duration persistence, and residual effects of various concentrations of these chemicals and benzyl benzoate were assessed in laboratory conditions with specially designed wells. Our data suggest that benzyl benzoate may not be effective when applied according to the manufacturers instructions, but may be effective when applied more frequently (i.e., three to four times a year) and for longer periods (up to 24 h) even with lower concentrations (0.4%).
Journal of Asthma | 1997
A. F. Kalpaklioglu; Yavuz Selim Demirel; S. Saryal; Zeynep Misirligil
Although anticoagulant properties of glycosaminoglycan heparin are primary in medicine, a variety of other biological functions related to heparin have been suggested. Since heparin is a selective inhibitor of inositol triphosphate (IP3) receptors that are involved in release of calcium in mast cells and many other cells, it is possible that heparin may act as a natural anti-inflammatory molecule and modify these reactions. Therefore, the purpose of the present study was to determine the role of heparin in allergic inflammatory responses: the pulmonary reaction and the cutaneous response, in a double-blind, placebo-controlled, crossover randomized trial. To evaluate the effect of heparin on methacholine-induced bronchoconstriction, nebulized heparin (20,000 units) was administered to 12 asthmatics and nonspecific challenge was performed immediately thereafter. Measurements of Raw and SGaw were obtained before and 1 hr after nebulization of heparin. In 12 other allergic subjects, heparin (25 U/kg) was given intravenously 10 min before skin prick test. We demonstrated that pretreatment with heparin reduced skin test reactivity from 24.06 +/- 1.2 mm to 18.26 +/- 2.27 mm and increased the methacholine PC20 value from 1.69 +/- 0.48 mg/ml to 8.14 +/- 3.11 mg/ml (p < 0.05), but did not prevent an increase in Raw and/or a decrease in SGaw. Heparin modified the methacholine-induced bronchoconstrictor response, but this did not reflect a protective effect in airway resistance and specific conductance. These data suggest that anti-inflammatory effects of heparin are time-dependent and/or that heparin may have a transient inhibitory role in allergic reactions.
International Archives of Allergy and Immunology | 2012
Gülfem Çelik; Ömür Aydın; Figen Dogu; Funda Erol Cipe; Ayşe Boyvat; Aydan Ikinciogullari; Aynur Akyol; Yavuz Selim Demirel
Background: Diagnosing immediate hypersensitivity to β-lactam antibiotics is still a significant problem. Recently, a new penicillin testing reagent was introduced to the market. In this study, the recommendations of the European Network of Drug Allergy (ENDA) for the diagnosis of immediate reactions to β-lactams were followed, and the negative predictive value of this approach with currently available reagents was assessed. Methods: Eighty patients (age range: 6–74 years) with a history of immediate reactions to β-lactams were included. All cases underwent skin testing with benzylpenicilloyl-polylysine (PPL) and minor determinant mixture (MDM), followed by the culprit drug if necessary. If this step was negative, a drug provocation test was offered. If this step also yielded a negative result, then the patients were recommended to use β-lactam antibiotics in future whenever their use was indicated. Results: Overall, 29 patients (36.2%) were diagnosed as β-lactam allergic. The majority of the cases (72.4%) were diagnosed by positive skin tests to either PPL or MDM, whereas 10.3% were diagnosed by skin testing with culprit drugs and 17.2% with drug provocation tests. Regarding the use of the tested drug in the long term, almost half of the contacted patients had had an indication to use the tested drug and the majority had taken the whole course without problems. Conclusions: Although currently available new penicillin tests provide sufficient allergy data, all the steps recommended by ENDA should be followed in the diagnosis of immediate reactions to β-lactams. If these steps are negative, the patients usually tolerate β-lactams and only a few develop mild, non-life-threatening reactions in the long term.
Allergologia Et Immunopathologia | 2014
Ömür Aydın; Gülfem Çelik; Z.P. Önen; İnsu Yılmaz; Seçil Kepil Özdemir; Öznur Akkoca Yildiz; Dilşad Mungan; Yavuz Selim Demirel
BACKGROUND-OBJECTIVE Several factors might affect the adherence to treatment in patients with asthma and COPD. Among these factors, the effect of religious beliefs and behaviours has been less studied so far. In this study, the effect of fasting on drug use behaviours of patients with asthma and COPD were comparatively analysed. METHODS A total of 150 adult patients with asthma and 150 adult patients with COPD were consecutively enrolled into this cross-sectional study. The patients were asked whether they fast during Ramadan and if the answer was yes, they were kindly asked to respond to further questions related to use of inhaled medications during that particular time. RESULTS The majority of the cases from both groups [98 (65.3%) of asthma patients and 139 (92.6%) of COPD] were fasting during Ramadan. The majority of the patients with COPD (n=126; 90.6%) reported that they quitted their regular therapy basis during Ramadan. On the other hand, the majority of asthma patients used their controller inhaled medications during Ramadan and preferred to use them on iftar and sahur times (n=81, 82.6%). CONCLUSION Our results showed that in a Muslim population, the patients with asthma and COPD do not feel their diseases to be an inhibitory factor for fasting during Ramadan. However, fasting seems to be an important determining factor in medication compliance by modifying the drug use behaviours in each group in a different way. Therefore, the patients should be informed about the effects of fasting on their disease and the allowed drugs during fasting.
Journal of Asthma | 2002
Gülfem Çelik; Dilşad Mungan; Faruk Özer; Dane Ediger; Sevim Bavbek; Betül Ayşe Sin; Yavuz Selim Demirel; Zeynep Misirligil
The factors underlying analgesic intolerance (AI), particularly the role of ethnic characteristics, are readily not clear. In this trial, we aimed to assess the predictive features of AI in Turkish subjects. One hundred and ninety patients with AI were enrolled into the study conducted in our tertiary care clinic. The types of drug causing adverse reaction(s) and types of reaction(s) were recorded. The presence of atopy was assessed by skin prick tests. According to the results, the most frequently intolerated analgesic was acetyl salicylic acid (72.1%), followed by nonsteroidal anti-inflammatory drugs (68.4%) and paracetamol (15.8%). Urticaria/angioedema (52.6%) and asthmatic response (40.5%) were the most common reactions to analgesics. Compared with the general adult population of Turkey, the rate of atopy was found be higher in patients with AI and asthma (25% vs. 45%, p = 0.004) but comparable in patients with AI but no atopic disorder (25% vs. 29.2%, p > 0.05). In conclusion, subjects exhibiting intolerance to analgesics have particular features in our population; the presence of atopy in these subjects seems to be associated with the coexistent asthma rather than the drug allergy itself.