[Diagnostic values of the clinical characteristics of chronic cough].
OBJECTIVE
To evaluate whether the clinical characteristics of chronic cough were helpful in determining its specific causes.


METHODS
Patients with chronic cough were evaluated by a validated systematic diagnostic protocol. The patients with identified single cause were divided into 4 groups accordingly: cough-variant asthma (CVA), upper airway cough syndrome (UACS) or post-nasal drip syndrome (PNDS), eosinophilic bronchitis (EB), gastroesophageal reflux related cough (GERC), and the characteristics of the timing, character, onset and associated manifestations of chronic cough in different causes were compared.


RESULTS
A total of 196 patients met the inclusion criteria, including 55 with EB, 45 with UACS, 50 with CVA and 46 with GERC. No significant difference was found in age, gender and course among EB, UACS, CVA and GERC. The incidence of nocturnal cough in CVA was 26.0% (13/44), significantly higher than in EB (9.1% (5/55), chi2 = 5.272, P<0.05), UACS (2.2% (1/45), chi2 = 10.657, P<0.01) and GERC (0% (0/46), chi2 = 13.833, P<0.01). The specificity of nocturnal cough for CVA was 95.9%. The sensitivity and specificity of cough associated with meals in GERC was 52.2% (24/46) and 83.3%, and regurgitation associated symptom in GERC were 69.6% (32/46) and 80.0%, which were significantly higher than other groups. The incidence of postnasal drip, rhinitis associated symptom and case history of nasal diseases in UACS were 66.7% (30/45), 88.9% (40/45) and 82.2% (37/45), and the specificity of them were 89.4%, 65.6% and 63.6% respectively.


CONCLUSIONS
The timing character and some associated symptoms of chronic cough are useful in predicting a single cause.
Lai
Ke-fang
KF
State Key Laboratory of Respiratory Disease, Guangzhou Medical College, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical College, Guangzhou 510120, China.
Chen
Ru-chong
RC
Lin
Ling
L
Shen
Lu
L
Zheng
Yan-bing
YB
Wang
Fa-xia
FX
Li
Bin-kai
BK
Jiang
Hua
H
Xiao
Huan
H
Liu
Chun-li
CL
Zhang
Qing-ling
QL
Xie
Jia-xing
JX
Luo
Wei
W
Chen
Qiao-li
QL
Zeng
Yun-xiang
YX
Zhong
Shu-qing
SQ
Zhong
Nan-shan
NS
D000293:Adolescent; D000328:Adult; D000368:Aged; D001249:Asthma / Q000150:complications / Q000175:diagnosis; D002908:Chronic Disease; D003371:Cough / Q000175:diagnosis* / Q000209:etiology*; D003937:Diagnosis, Differential; D005260:Female; D005764:Gastroesophageal Reflux / Q000150:complications / Q000175:diagnosis; D006801:Humans; D008297:Male; D008875:Middle Aged; D009668:Nose Diseases / Q000150:complications / Q000175:diagnosis; D012220:Rhinitis / Q000150:complications / Q000175:diagnosis; D055815:Young Adult