The Clinical Treatment And Prognosis Of Eosinophilic Bronchitis

Eosinophilic bronchitis (EB) presents with chronic cough and sputum eosinophilia, but without airway hyperreactivity. EB is the common cause of chronic cough. The long-term outcome of EB is unclear now..EB responds well to inhaled corticosteroids, but the treatment course is unknown. The aim of this study is to investigate the clinical characteristics, the long-term outcome, the risk factors of recurrence, the effects of different treatment course with inhaled corticosteroids, the relationship of cough severity and sputum eosinophil count in EB patients.PartΙThe Clinical Characteristic and Prognosis of Eosinophilic BronchitisObjectiveTo investigate the clinical characteristics of eosinophilic bronchitis (EB), the long-term outcome of EB and the risk factors of recurrence.MethodsThe patients with EB were analyzed retrospectively. The clinical characteristics included cough timing, inducing factors , associated symptoms, allergic history were compared with 74 patients with cough variant asthma (CVA). Patients were followed up by telephone annual. Induced sputum, spirometry and airway hyper-responsiveness rest were performed when cough reccur. The clinical characteristics, induced sputum, spirometry and treatment were compared between recurrence group and unrecurrence group. The logistic regression analysis were conducted for the indexs aboved.Results1. A total of 154 patients with EB (83 men and 71 women) were enrolled. 101 patients (47 men and 49 women) were followed up. The mean age was 40±10 years old, the duration of cough was 6 (1-144) monthes, the median period of follow up was 24 (12-84) monthes.2. 82 patients with single cause of EB. 49 patients with multiple cause of allergic rhinitis (53%), 8 patients with multiple cause of gastroesophageal reflux related cough, and 8 patients with multiple cause of nasal sinusitis.3. 64.94% EB patients presented dry cough. The rate of daily cough was higher in EB than CVA (63.64% vs 40.54%, P<0.05), but the rate of nocturnal cough were lower (22.97% vs 7.14%, P<0.05). Stimulatory odors, dust and cold air were inducing factors of cough. There were no significant difference between EB patients and CVA patients in the rate of allergic rhinitis history, cell differential of induced sputum, FEV1%, FVC% and the positive rate of SPT (P>0.05). The MMEF% was higher in EB than CVA (85.09% vs 68.48%,P<0.05).4. Among 101 patients of followed up, 47 patients (46.53%) reccur after treatment. 24 patients reccur over 2 times, 5 patients developed asthma.5. The rate of men (59.57% vs 38.78%) and AR (38.30% vs 16.33%) are higher in recurrence group (P=0.042, 0.024). The rate of regular treatment with ICS (budesonide 400μg/d or fluticasone 250μg/d over 4 weeks) was lower in recurrence group (46.81% vs 69.39%,P=0.025). There were no significant differences between recurrenc group and no-recurrence group in cell differential of induced sputum, FEV1%, FVC%, FEV1/FVC, MMEF% and the rate of SPT positive rate.6. Logistic analysis showed that AR increased the risk of EB recurrence [B=1.126;P=0.029;Exp(B)=3.08;95%CI(1.12-8.45)]. Regularly use with low dose of ICS over 4 weeks could reduce the risk of recurrence [B=-1.234;P=0.009;Exp(B)=0.291;95%CI(0.115-0.737)].Conlusions1. Cough timing and parameters of small airway function may conduce to the identification between EB and CVA.2. Recurrence is the common outcome of EB. Few of patient develop asthma.3. AR increase the risk of recurrence.4. Regularly treatment with low dose ICS reduce the recurrence of EB. Part II Different Treatment Course with Inhaled Corticosteroids for Eosinophilic BronchitisObjectiveTo investigate the effects of different treatment course with inhaled corticosteroids, the relationship of cough severity and sputum eosinophil count in EB patients..MethodsNosmoking EB patients that without respiratory infection in previous 8 weeks and without treatment of corticosteroids ,antihistamines, leukotriene receptor antagonist in previous 4 weeks were enrolled, and randomly divided into three groups with inhaled budesonide 200μg twice daily via a turbohaler for 4 weeks, 8 weeks and 16 weeks respectively. Cough severity was assessed by cough symptom score and visual analogue scale (VAS) at baseline and during the treatment period. Airway inflamation was assessed by sputum eosinophil percentage (Eos%). All the patients were followed up for 6 months after treatment. The sputum Eos% were compared among different cough symptom score in EB patients without allergic rhinitis . The relationship between VAS and sputum Eos% were analysed.Results1.A total of 58 patients were recruited and followed up. With 20 patients in 4 weeks treatment group, 21 patients in 8 weeks treatment group and 17 patients in 16 weeks treatment group. There were no significant difference among three groups in sex, age, cough duration, allergic rhinitis history, cell differential of induced sputum, pulmonary ventilation function (FVC%,FEV1%,MMEF%), positive rate of SPT ( P>0.05).2. The effects in EB patients with different treatment courses of inhaled corticosteroids:①There was no significant difference among three groups (4 weeks treatment group, 8 weeks treatment group and 16 weeks treatment group) in daily cough score before treatment (P=0.706). The daily cough score after treatment decreased in all three group (P<0.05), which was lower in 16 weeks group and 8 weeks group than 4 weeks group (P=0.009, 0.022). The rate that VAS decreased over 80% after treatment were higher in 8 weeks group and 16 weeks group (76.19% vs 40%, 88.24% vs 40%, P=0.019, 0.003), but there was no significant difference between the 8 weeks group and 16 weeks group (76.19% vs 88.24%, P=0.341).②The sputum eosinophil percentage decreased in all three group after treatment. The rate that sputum eosinophil recovered to normal level (Eos%<2.5%) was 50%, 71.42%, 82.35% in 4, 8, 16 weeks treantment group respectively. There were no significant differences among three groups (P=0.099).③The rate of recurrence was 41.18%, 26.32%, 17.65% in 4, 8, 16 weeks treatment group respectively. There are no significant difference among three groups (P=0.305).3. The relationship between cough symptom and sputum Eos%:①There was no significant difference in the percentage of Eos, neutrophiles, macrophage, lymphocyte in sputum among the 4 groups with different cough symptom score before treatmen (P=0.286, 0.319, 0.160, 0.999). The VAS before treatment was not correlated with sputum Eos% (r=0.103, P=0.459).②The improvement rate of VAS after 4 weeks treatment was neither correlated with the percentage of sputum eosinophils before treatment, nor correlated with the change of sputum eosinophils (r=-0.100, -0.087,P=0.538, 0.637).Conclusions1. Eosinophilic brochitis should be treated with low-dose inhaled budesonide for at least 8 weeks.2.The relationship between cough severity and sputum Eos% is unparallel.