Blood eosinophils as a predictor of treatment response in adults with difficult-to-treat chronic cough.

There is lack of evidence on the role of blood eosinophil count (BEC) as a predictor of treatment response in patients with chronic cough. The study aimed to evaluate BEC as a predictor of treatment response in all non-smoking adults with chronic cough and normal chest radiograph referred to cough clinic and in a subgroup of patients with chronic cough due to asthma or non-asthmatic eosinophilic bronchitis (NAEB). This prospective cohort study included 142 consecutive, non-smoking patients referred to our cough centre due to chronic cough. The management of chronic cough was performed according to the current recommendations. At least a 30-mm decrease of 100-mm visual analogue scale in cough severity and a 1.3 points improvement in Leicester Cough Questionnaire were classified as a good therapeutic response. There was a predominance of females (72.5%), median age 57.5 years with long-lasting, severe cough (median cough duration 60 months, severity 55/100 mm). Asthma and NAEB were diagnosed in 47.2% and 4.9% of patients, respectively. After 12-16 weeks of therapy, a good response to chronic cough treatment was found in 31.0% of all patients. A weak positive correlation was demonstrated between reduction in cough severity and BEC (r=0.28, p<0.001). Area under the curve for all patients with chronic cough was 0.62 with the optimal BEC cut-off for prediction of treatment response set at 237 cells·µL-1 and for patients with chronic cough due to asthma/NAEB was 0.68 (95% CI 0.55-0.81) with the cut-off at 150 cells·µL-1. BEC is a poor predictor of treatment response in adults with chronic cough treated in the cough centre.

Does bronchial hyperresponsiveness predict a diagnosis of cough variant asthma in adults with chronic cough: a cohort study.

Bronchial hyperresponsiveness is a typical, but non-specific feature of cough variant asthma (CVA). This study aimed to determine whether bronchial hyperresponsiveness may be considered as a predictor of CVA in non-smoking adults with chronic cough (CC). The study included 55 patients with CC and bronchial hyperresponsiveness confirmed in the methacholine provocation test, in whom an anti-asthmatic, gradually intensified treatment was introduced. The diagnosis of CVA was established if the improvement in cough severity and cough-related quality of life in LCQ were noted.The study showed a high positive predictive value of bronchial hyperresponsiveness in this population. Cough severity and cough related quality of life were not related to the severity of bronchial hyperresponsiveness in CVA patients. A poor treatment outcome was related to a low baseline capsaicin threshold and the occurrence of gastroesophageal reflux-related symptoms. In conclusion, bronchial hyperresponsiveness could be considered as a predictor of cough variant asthma in non-smoking adults with CC.

Chronic cough related to the upper airway cough syndrome: one entity but not always the same.

PURPOSE: Upper airway cough syndrome (UACS), described as chronic cough (CC) associated with allergic (AR), non-allergic rhinitis (NAR) or chronic rhinosinusitis (CRS), is one of the major causes of CC. We aimed to characterize a cohort of UACS patients with special attention to differences between patients with AR and NAR. METHODS: A prospective analysis of clinical data of patients, diagnosed with UACS between 2015 and 2018. RESULTS: There were 143 patients diagnosed with UACS, median age 52 years, women predominance (68.5%), The group comprised of 59 (41%) AR and 84 (59%) NAR subjects, CRS diagnosed in 17 (12%). Median cough duration: 48 months (IQR 24-120), median cough severity (VAS)-60 mm (IQR 42-78), median Leicester Cough Questionnaire (LCQ) score-11.3 (IQR 8.7-13.7), never-smokers: 70%. The most common symptoms: PND (62%), rhinorrhea (59%), nasal congestion (54%), abnormalities of sinus CT: septum deviation (62%), turbinates hypertrophy (53%), mucosal thickening (53%). UACS as the only cause of CC, was presented in 20 patients (14%). We found no differences between patients with AR and NAR in terms of age, gender, duration and severity of cough, BMI, blood eosinophil count, total IgE and FeNO. AR was associated with higher comorbidity of asthma than NAR (54% vs 35%, p = 0.019). Abnormalities in sinus CT scan were more frequently found in patients with NAR than AR (p = 0.018). CONCLUSION: NAR is the most common upper airway disease associated with UACS. Clinical characteristics of UACS patients with AR and NAR are similar with only minor differences between these groups. It seems reasonable to plan further studies concerning relationship of NAR and cough sensitivity, also in terms of potential similar neurogenic mechanism.

Is a normal chest radiograph sufficient to exclude pulmonary abnormalities potentially associated with chronic cough?

INTRODUCTION: There are few original studies on the true role of normal chest radiograph (CXR) in exclusion of pulmonary conditions that may be associated with chronic cough. Thus, the aim of the study was to assess whether a plain CXR is a sufficient tool to exclude relevant pulmonary causes of chronic cough. MATERIAL AND METHODS: A retrospective analysis of chest computed tomography (CT) scans in non-smoking patients with chronic cough and normal CXR was performed. The percentage of individuals in whom chest CT revealed relevant abnormalities was compared with the percentage of patients with irrelevant findings or normal chest CT scans. The negative predictive value (NPV) of the CXR in diagnosing the causes of chronic cough was calculated as a proportion of true negative CXRs (normal CXR AND irrelevant CT findings OR normal CT scan) to all negative CXRs (all patients, who had both a CXR and CT scan). RESULTS: The study group consisted of 59 adult patients with chronic cough, normal CXR and CT scan performed to diagnose the cause of chronic cough. In 21 patients (21/59, 36%), chest CT revealed abnormalities that were classified as relevant to chronic cough. The most frequent were: bronchiectasis (7/59, 11.9%), bronchial wall thickening (6/59, 10.2%) and mediastinal lymphadenopathy (5/59, 8.5%). The NPV of a CXR in diagnosing the causes of chronic cough was 64%. CONCLUSIONS: In conclusion, the NPV of CXR in diagnosing pulmonary causes of chronic cough is relatively low. Thus, plain CXR seems to be insufficient to exclude pulmonary diseases potentially associated with chronic cough.