Evaluation of Chronic Cough in Children : A Prospective Study in a Tertiary Care Hospital

Background : Chronic cough is a common complaint in children which causes distress, and affects the quality of life of parents and children. While cough may be seen as a common condition of childhood without serious consequences, ignoring a cough that may be the sole presenting symptom of an underlying illness can lead to delayed diagnosis and progression to a chronic respiratory morbidity. Objective : To evaluate the specific diagnosis and prognosis of chronic cough in children. Methods : A prospective study was done on children with chronic cough (history of cough>8 weeks) referred to Dhaka Shishu (Children) Hospital, a tertiary hospital.Children aged 2 to 8 years with chronic cough referred by the general physicians, pediatricians and other peripheral hospitals were the study subjects. Exclusion criteria were children with immune-deficiency,congenital anomalies of lung,congenital heart disease, gastro-intestinal disorders (e.g. gastro-esophageal reflux, peptic ulcer disease), in born error of metabolism (e.g. cystic fibrosis) and other chronic conditions (e.g. gross neurodevelopmental delay). The evaluation of chronic cough was based on simple principles: careful history-taking concerning the characteristics of the cough, full clinical examination to look for any associated symptoms and relevant investigations done. Underlying diagnoses and outcomes were ascertained after follow-up for a period of six months and treatment was given as per the management protocol of the hospital. Results : The most common final diagnosis was allergic rhinitis (31%), followed by asthma (28.6%), rhinitis coexisting with asthma (23.8%), post viral cough (16.6). Cough resolved in 54.8%, partially improved in 40.5% and persisted in 4.7% of patients. Conclusion : Allergic rhinitis with or without co-existing asthma was the commonest cause of chronic cough in children referred to this hospital.


Introduction
Chronic cough is typically defined as a cough that persists for longer than 8 weeks; this is the most common presenting symptom of children for which parents seeks medical treatment in an ambulatory setting. 1,24][5] It is a common problem that can cause anxiety in parents for which they typically seek five or more medical consultations prior to referral to respiratory specialists.Despite chronic cough in children accounting for substantial direct and indirect costs for health service providers, patients and their families, it remains an under-recognized and inadequately researched cause of morbidity in children.Inaccurate diagnosis and in appropriate investigation and management of chronic cough in children are not uncommon 6 , thus presents a challenge for the pediatricians which necessitates a clear need to improve chronic cough management in children. 7ronic cough in children is a common presenting symptom, and the evaluation still contains a major challenge for pediatricians due to the scarcity of data.There are few prospective cohort studies addressing the causes of chronic cough.Thus, we conducted a prospective study to evaluate chronic cough in children.Total number of follow-up visit were varied according to the need of the individual patient.At least 6 visits and maximum 12 or more whatever needed.But underlying diagnoses and outcomes were ascertained after follow-up for a period of six months of all study patients.Final diagnoses was made by the pediatricians who was attending the patient.

Original Article
In this study outcome of chronic cough was recorded as completely resolved, i.e. no or little cough present; partially resolved, i.e. some cough; or persistent, i.e. no resolution of cough upto 6 months follow up.Appropriate statistical analysis was done with SPSS version 20.

Results
Total 60 children with chronic cough were enrolled in the study.During 6 months follow-up period 18 patients were dropped out from the study (7 diagnosed as such diseases that they were excluded, 11 missed regular follow up to 6 months).Finally, 42 children with chronic cough were completed the follow up until 6 months.Therefore, these 18 dropped out children were excluded from the analysis.
Forty-two children were completed the follow up period of 6 months.Among them mean age was 5.0±2.9years.Twenty-seven patients (64%) were male.The median cough duration was 15.12 weeks (quartile range: 8.12-52 week).
The sources of cases were referral by general physicians (47.6%), followed by pediatricians (26.2%) and peripheral hospitals (26.19%) shown in Table-I.The primary diagnosis with which the children were referred to our hospital for further evaluation and management.The most common reasons for referral were non-specific chronic cough (52.4%), followed by asthma (38.1%), allergic rhinitis (7.1%), asthma and allergic rhinitis co-existing together (2.4%) and none with post-viral cough (Table-II).In the present study most common final diagnosis was allergic rhinitis (31%) followed by asthma (28.6%), co-existing asthma and allergic rhinitis (23.8%) and post viral cough (16.6%) shown in Table-V.Non-specific chronic cough 0(0%) After complete evaluation, the children were treated as per the final diagnoses according to our hospital's management protocol.The patients were followed up by a study Pediatrician for a period of 6 months by regular periodic visit (when ever necessary) and thereby final outcome was studied.Among the studied children, 54.8% had complete resolution of cough, 40.5% partially resolved and 4.7% had persistent cough.Non-specific chronic cough 0 0 0

Discussion
A prospective study was done to evaluate chronic cough in children between age group 2-8 years (mean 5.0±2.9).Marchant et al. 9 found children with a mean age of 4.5 ± 3.7years in their study which is comparable to our study.The different ages of children studied may play an important role in the causes of chronic cough.In addition to the differences in practice settings, the etiologies and burden of chronic cough are also potentially influenced by age. 10 The present study showed that majority of the cases were labeled as non-specific chronic cough on referral.Lahiri et al found cough variant asthma as the most referral cause of chronic cough in children in their study, which is different from our study. 11r study found 19.04% of the children with a family history of atopy.In a study Sears et al described family history of atopy in 41% patients.Family history of asthma, rhinitis and skin atopy reflects the same pattern and such a history helps in alerting the physician, though it may not always be present. 12 the present study, we have found that the diagnostic categories for chronic cough in children are heterogeneous and the final diagnoses were allergic rhinitis, asthma, asthma with allergic rhinitis and post viral cough.In contrast to our study, published prospective studies showed in affluent countries asthma as being the most common cause of chronic cough. 13,14ere were several limitations in our study regarding duration, sample size, single center and most importantly scarcity of comparison with other studies.We also could not compare the prognosis of the children in our study with other studies specially of Bangladesh due to lack of similar type of study.A prospective multi-center study for longer duration with regular, longer follow up period and a universal evaluation protocol would help us in further understanding the etiologies and outcome of chronic cough in children.

Conclusion
Chronic cough is an under-recognized and inadequately researched cause of morbidity in children.This study found that allergic rhinitis with or without co-existing asthma is the commonest cause of chronic cough in children observed in this hospital.

2017 n Volume 9 n Number 1 265
Evaluation of Chronic Cough in Children: A Prospective Study in a Tertiary Care Hospital MMZ Islam et al.
tract infections, and smoke exposure.The physical examination included complete ear, nose, and throat, respiratory and cardiovascular examinations looking particularly for clubbing, chest deformity, cardiac abnormality or auscultatory abnormality.Investigations and treatment were at the discretion of the attending pediatricians as per the hospital protocol.For this study results were counted as abnormal if present-abnormal lung auscultatory finding (mainly obstructive), blood eosinophil count>0.3x 10 9 /L, blood IgE level> 100 IU/L, or CXR shows any abnormal findings.

Table II : Referral diagnosis
Most of the chronic cough patients (54.76%) were found to have persistent nasal symptoms (e.g.runny nose, nasal blockage, polyp, septal deviation etc.) Family history of atopy was found in 19.04% children.Physical examination showed that 14.28% of patients had pale and swollen nasal mucosa and 11.9% had eczema; no other major anomalies were identified on physical examination.None of the patients had serious underlying lung disease (Table-III).

Table V : Final diagnosis
Table-VI shows the diagnosis wise prognosis.