Epidemiology and current status of allergic rhinitis and asthma in Thailand -- ARIA Asia-Pacific Workshop report.

The allergic diseases of the airway, i.e. allergic rhinitis and asthma, are on the increase in Thailand and their prevalence shows no signs of abating. When compared with a previous study, the incidence of wheezing had increased 4 fold (from 4.2% to 18.3%), and allergic rhinitis increased nearly 3 fold (from 17.9% to 44.2%). The results of the ISAAC phase III study revealed that the frequency of allergic diseases of the respiratory tract increased significantly from the ISAAC phase I survey performed in 1995; i.e. asthma increased from 12.2% to 14.5%, and allergic rhinitis from 37.9% to 50.6%. Allergic rhinitis exerts a major impact on the quality of life of Thai patients. The results of skin prick testing have indicated the leading causes of indoor (house-dust mites, house dust, cockroaches, dogs and cats) and outdoor pollen (Bermuda grass, para grass, sedge, careless weed) allergens. Molds (represented by Cladosporium), although prominent in an aeroallergen survey, returned a low percentage of positive skin prick reactions, and therefore, were considered low in allergenicity. In Thailand, there are clinical practice guidelines for both allergic rhinitis and asthma which are comparable to the international guidelines like ARIA and GINA. Sufficient kinds of pharmacotherapy are on the National List of Essential Drugs. Yet due to the limited number of trained allergists, many patients are seen by general physicians, and often, the appropriate diagnostic tests and treatments are not provided. In addition, the financial burden for quality health care may be prohibitive for those without private health insurance in spite of the implementation of a universal health care system for all Thai citizens, which is less than optimal.

A non-comparative trial of the efficacy and safety of fexofenadine for treatment of perennial allergic rhinitis.

An open-label, non-comparative study was performed in three Otolaryngology centers in Bangkok, Thailand, to assess the efficacy, safety and tolerability of fexofenadine in Thai patients with perennial allergic rhinitis. Altogether 101 perennial allergic rhinitis patients were included, 33 males and 68 females. Mean age was 33 years, average duration of symptoms was 6 years. All patients received fexofenadine hydrochloride 120 mg once daily (OD) in the morning for 2 weeks. Patients recorded their allergy symptoms daily using a 5 point rating scales in the diary card. At the end of 2 weeks, patients and investigators assessed the overall efficacy of treatment. Adverse events and onset of symptom relief were also recorded by every patient. Blood test and ECG were performed before and after treatment in one center (Siriraj Hospital). Total symptom scores and nasal scores decreased significantly from a baseline at 1 week and 2 weeks after treatment (p < 0.05). The mean onset of symptom relief was 2 hours and 12 minutes. The global assessment of the treatment by patients and investigators showed significant concordance. There was no significant change in either the vital signs, laboratory tests or ECG. The incidence of treatment related adverse events was 8% but all were mild and easily tolerated. Drowsiness was reported from only one patient. This study suggests that fexofenadine 120 mg once daily was an effective, safe and well tolerated treatment for perennial allergic rhinitis in Thai patients.

Epidemiology of rhinitis in Thais: characteristics and risk factors.

A questionnaire survey was performed on 3,124 subjects living in Bangkok and its vicinity. The cumulative prevalence of chronic rhinitis (CR) was 13.15% (95% CI = 13.13-13.17). The characteristics of CR subjects, i.e. age group, current occupation, associated allergy, family history of atopy, cigarette smoking and drinking habits were totally different from the non CR group, except for sex preponderance. The possible risk factors for developing CR in this group were high income occupation, presence of associated allergy, family history of atopy, smoking and drinking habits. When CR subjects were further classified into "allergic" and "non-allergic" CR groups by using the presence of associated eye symptoms and known provoking factors as the differential criteria, there was no significant difference in all parameters compared between the two groups, i.e. age, sex, current occupation, associated allergy, family history of atopy, smoking and drinking habits, frequency of occurrence of each nasal symptom, seasonal variation of the symptoms, effect of moving to live in the big city, presence of pets in the house and effect of changing occupation, except for the number of nasal symptoms which was significantly higher in the "allergic" CR group.

Characteristics of atrophic rhinitis in Thai patients at the Siriraj Hospital.

The common characteristics of primary atrophic rhinitis were studied in 46 Thai patients. From history and demographic data the female to male ratio was found to be 5.6 to 1. The significance of environmental factors was supported by the findings that 69.6% were people from rural areas and 43.5% were industrial workers but a hereditary factor has not been confirmed. The results of the blood tests did not elucidate iron deficiency anemia or nutritional deficiency as the cause of primary atrophic rhinitis. However, all nasal swab cultures yielded pathogenic organisms where Klebsiella species especially, K. ozaena, were the most common bacteria isolated which were 100% susceptible to cephalosporins. This finding together with the evidence of sinusitis seen in 58.7% of either plain x-rays or CT scans, was suggestive of the important role of infection in atrophic rhinitis. Atrophic change of the mucosa and bone with widening of the nasal cavity were constant findings in the CT scans but the developmental anomaly of the maxillary antrum was found in only 15.2%. The histological study showed characteristic changes especially squamous metaplasia and 80% of the cases were compatible with the Type II histopathological classification, i.e. vasodilatation of the capillaries. The mucociliary function was proven to be impaired in accordance with the loss of cilia. The evidence of Type I allergy demonstrated by skin testing, which was obvious in 85%, is highly suggestive of allergic/immunologic disorders. Although many factors have been cited previously as the possible cause of primary atrophic rhinitis, the common characteristics found in our patients indicate that only bacterial infection, environmental factors and allergic/immunologic disorders could be one or more of its multifactorial etiology and should be further investigated.

Nasal endoscopic findings in patients with perennial allergic rhinitis.

Nasal endoscopy was carried out in 83 patients with perennial allergic rhinitis to evaluate endonasal anatomic variation and to find the correlation between the symptoms of patients and the endoscopic findings. All of the patients had nasal symptoms, 7.2% of the patients were runner, 7.2% were blocker and 85.6% were both. 86.75% of the patients had allergy-related symptoms, i.e. throat symptoms (73.5%), sinus headache (50.6%), and smell disturbance (10.8%). 95.2% of patients had abnormal endoscopic findings, i.e. deviated nasal septum (72.3%), abnormal middle turbinate (49.4%), narrowing of the entrance into the frontal recess (30.1%), septal spur (25.3%), obstruction of the entrance into the frontal recess (19.3%), nasal polyps (15.7%), mucopurulent discharge (14.5%), inferior turbinate hypertrophy (10.8%), abnormal uncinate process (9.6%), abnormal ethmoid bullae (7.2%), and enlargement of aggar nasi cells (2.4%). There was no significant correlation between each symptom and each endoscopic finding. However, there was a significant correlation between sinus headache and all of the combined abnormal endoscopic findings (P<0.05). These findings suggested that variations in endonasal anatomy was not by itself a pathology or a cause of symptoms. However, a combination of these variations may narrow the cleft of the ostiomeatal unit and cause contact area or stenosis, which predisposed patients to persistent symptoms, recurrent infection or resistance to therapy in patients with perennial allergic rhinitis. The endoscope might be a very useful tool for allergists, immunologists, and rhinologists, who work in the nose to deal with these cases.

Efficacy of spiramycin as an alternative to amoxicillin in the treatment of acute upper respiratory tract infections.

This study compared the efficacy of spiramycin with that of amoxicillin in treating patients with acute community-acquired upper respiratory tract infections (URTIs). The study was an open, randomised, comparative parallel design and patients received either spiramycin 3 MIU (2 tablets, 500mg or 1.5 MIU per tablet) twice daily after meals, i.e. 6 MIU/day for 7 days or amoxicillin (500 mg/capsule) 1 capsule three times daily after meals, i.e. 1500 mg/day for 7 days. Patients attending the ENT outpatient clinic at Siriraj Hospital in Bangkok for treatment of acute URTIs were included in the study after giving their informed consent. Eligible patients comprised those aged 18 years and over, of either gender, who had at least two of the following symptoms: fever (>/=38 degrees C oral), nasal discharge/obstruction, sore throat, cough and/or hoarseness of voice that did not require parenteral drug therapy or hospitalisation. A total of 99 patients were included in this study, 49 patients received spiramycin and 50 received amoxicillin. Of the 45 assessed patients treated with spiramycin, 40 were judged by the investigators as a 'success' (89%), and five were judged a 'non-success' (11%), compared with 48 assessed patients in the amoxicillin group where 40 patients were classified as a 'success' (83.3%) and 8 were judged a 'non-success' (16.7%). No statistically significant differences between treatments were demonstrated regarding the overall efficacy of treatment. This study demonstrated that the prescribed regimens of spiramycin and amoxicillin were similarly effective in the treatment of adult acute URTIs. The tolerability of both drugs was also similar. Furthermore, it was noted that the convenient twice-daily dosage regimen of spiramycin may allow better patient compliance.

The first naso-sinus laboratory for cadaver preparation in Thailand.

The first naso-sinus laboratory has been set up in Siriraj Hospital for better training of rhinosurgeons. The specimens used for practice operation are the entire nasal cavities with all paranasal sinuses, taken from cadavers and preserved in 95% ethanol. The "Siriraj" sinus holder is specially designed and constructed to hold various sizes of specimens. It is made of plastic board and stainless steel screws; it is an inexpensive and simple device which can be afforded by every centre. With this naso-sinus laboratory, ENT residents and rhinosurgeons can achieve their skills in performing nasal endoscopy, endoscopic or microscopical sinus surgery and all kinds of sinus operations at their convenience.

A double-blind comparison of nasal budesonide and oral astemizole for the treatment of perennial rhinitis.

Sixty-nine outpatients with symptomatic perennial rhinitis were recruited to this double-blind, parallel-group study to compare budesonide nasal spray with oral astemizole. Following a 1-week run-in on placebo, 67 patients achieved a mean daily total symptom score of at least 4 (scoring for each symptom was 0 = none, 1 = mild, 2 = moderate, 3 = severe), and were randomized to study treatments - 33 to budesonide, 100 micrograms in each nostril morning and evening, and 34 to astemizole, one 10-mg tablet each morning, for a period of 4 weeks. No antihistamine preparations other than eye drops and no corticosteroids were permitted during the active treatment period. Patients recorded symptoms of blocked nose, runny nose, sneezing, itchy nose, sore eyes or runny eyes in diary cards each evening before retiring. Diary card data showed that there was significantly greater improvement in blocked nose, runny nose and runny eyes during the first 2 weeks of budesonide treatment than during the same period on astemizole. A similar, although non-significant, trend was observed for sneezing and itchy nose, but there was no apparent difference in the reporting of sore eyes. After 4 weeks, blocked nose and runny nose remained significantly less troublesome in the budesonide group. Both treatments were well-tolerated and no major adverse effects were reported. Patient ratings for treatment efficacy were significantly higher for budesonide than astemizole at both 2 weeks and 4 weeks.

Effect of allerglobuline injection on serum immunoglobulin levels in ENT patients.

Allerglobuline is a human gammaglobulin preparation which has been reported to have a protective effect against Type I allergic diseases and chronic infection of the upper respiratory tract both in adults and children. This study included 64 patients suffering from perennial allergic rhinitis and/or chronic infection of the nose, paranasal sinuses and pharynx. All patients received Allerglobuline 10 ml intramuscular injection once a week for 5 times then once a month for another 3 times. Blood samples were taken before the first and after the last injections to assay for the levels of Igs G, A, M and E. The therapeutic responses were evaluated after the fifth injections by dividing into 5 grades (from Grade I = excellent to Grade V = no response). Statistical analysis revealed that there was no significant difference between the pre- and post-treatment levels of Igs, G, A and M. But the level of IgE decreased significantly after 8 injections (p less than 0.001). There was no correlation between the level of immunoglobulins and grade of therapeutic responses. But the number of patients who respond satisfactorily to Allerglobuline treatment increased from 62.26% after 5 injections to 77.36% after 8 injections. This difference does not reach the statistically significant level but is noteworthy.

Ferns and their allergenic importance: skin and nasal provocation tests to fern spore extract in allergic and non-allergic patients.

In our recent survey, fern spores were found to be the third most common airborne air spora in the Bangkok atmosphere; therefore, the significance of fern spores as a causative allergen was assessed in patients with allergic rhinitis. By using the extract from the spores of Acrostichum aureum Linn, which is a widespread fern, an intracutaneous test was done in 226 allergic rhinitis patients and 61.5% of these patients reacted positively. Nasal provocation test by using the same kind of fern spore extract was also performed in 24 allergic rhinitis patients and the positive reaction occurred in 70.8%. When skin tests and nasal provocation tests were performed in a group of 20 nonallergic ENT patients, only 20% gave weakly positive skin test reactions and 15% gave mild reactions to the nasal provocation test. The authors concluded that fern spores are potentially allergenic and allergists should be aware that ferns could be an important aeroallergen.

Intranasal budesonide for the treatment of perennial rhinitis in Thai patients.

The efficacy and tolerability of a new intranasal glucocorticosteroid, budesonide, was evaluated in 28 Thai adult patients with perennial rhinitis. After one week pre-treatment observation period, the nasal spray was given as two puffs into each nostril twice daily (400 micrograms/day) for four weeks. The severity of all nasal symptoms decreased significantly after 1 week treatment reaching a minimal level after 2 weeks. The amounts of antihistamine tablets taken by the patients were also significantly reduced during the treatment with budesonide. Three patients reported adverse effects which were mild and easily tolerated. Morning plasma cortisol levels measured before and after four-week treatment in 15 patients revealed no significant changes. This study suggests that intranasal budesonide is an effective and well-tolerated treatment for perennial rhinitis.