The treatment of frequently ill children (FIC) with prolonged or chronic cough remains a complex challenge in pediatric practice. According to various authors, respiratory tract pathology accounts for 7.7% to 83% of chronic cough cases in the pediatric population [1-8].

The definition of chronic cough in children varies across guidelines. It is defined as lasting more than four weeks in the CHEST 2020 consensus statement [3], the Chinese Clinical Guidelines for the Diagnosis and Treatment of Cough in Children (2021) [4], and the Russian Clinical Guidelines on "Bronchitis" (2021) for pediatric age groups [5]. Similar views are expressed in other studies [6-8]. The British Thoracic Society guidelines define chronic cough in children as lasting more than eight weeks, while also recognizing prolonged subacute cough lasting four to eight weeks [9].

It has been established that chronic cough, when prolonged, affects sleep, quality of life, and children’s ability to play, thereby negatively impacting both children and their parents. This is further compounded by missed school days and repeated doctor visits [7,9-15]. Chronic cough in children is best considered a symptom of an underlying condition [16]. Regardless of the setting or age, children with chronic cough should be thoroughly evaluated using pediatric-specific protocols [17].

The most common causes of chronic cough in children are typically considered to be protracted bacterial bronchitis (PBB), asthma, and post-infectious cough. Other causes include tracheomalacia, primary ciliary dyskinesia, aspiration delay, pharyngeal abnormalities, Arnold’s reflex, and habitual cough [7-9,18]. The most likely causes of cough in children depend on age and can encompass more than 20 conditions [19]. A.A. Lebedenko, in the monograph Cough in Children: Unity of Theory and Practice (2014), identifies over 40 causes of cough in children, with approximately 25 related to chronic cough stemming from bronchopulmonary system pathology, ENT disorders, and extrapulmonary causes [20].

Alongside numerous causes of chronic cough in childhood, there have been isolated cases of delayed diagnosis of foreign bodies in the lower respiratory tract. Examples include a wheat sheaf present for 15 months [21], a metal tracheostomy tube in the tracheobronchial tree of a 14-year-old boy [22], and a bronchial foreign body persisting for about four years in a 7-year-old child, initially misdiagnosed as bronchial asthma episodes [23]. Bronchological examination identified 32 cases (4.8%) of delayed diagnosis of foreign body aspiration among 654 children with frequent cough. In the long term, 28.8% of these patients developed chronic respiratory issues, and six (18.8%) developed bronchiectasis [24].

According to some authors [25], in 70 cases where foreign bodies remained in the respiratory tract for extended periods, surgical interventions were required: lobectomy in 27 cases, pneumonectomy in 6, abscessotomy in 6, thoracostomy in 28, bronchotomy in 2, and wedge resection of a lung lobe in 1 case. Asymptomatic or prolonged occult foreign bodies in the bronchi can lead to various chronic complications in the long term, such as persistent pneumonia, bronchiectasis, abscesses, bronchopleural fistula, atelectasis, disability, and even death [26,27].

Delayed diagnosis of foreign body aspiration, ranging from 19.6% to 100%, often occurs when the aspiration event goes unnoticed by parents. As a result, children are treated by pediatricians for acute upper and lower respiratory tract conditions without clinical success [24,26,28-32]. Even when hospitalized with foreign bodies in the respiratory tract more than 24 hours after the event, 71.1% of patients developed complications: atelectasis with concurrent pneumonia and bronchitis in 5.26%, pneumonia in 13.2%, bronchitis in 47.4%, airway stenosis in 2.63%; and a fatal outcome due to bilateral tension pneumothorax was recorded in 2.63% of cases [29].

Thus, the etiology of prolonged and chronic cough is multifactorial, and considering the aforementioned data, timely diagnosis in children is a necessary condition to identify the cause of the cough for prompt treatment.

According to most researchers, the most effective diagnostic method for frequently ill children with prolonged cough is rigid bronchoscopy, particularly for the removal of inhaled foreign bodies with fewer complications [30].

Despite numerous studies, we found very few works addressing this issue from the perspective of a pediatric surgeon. The aim of our study was to identify the cause of prolonged cough in frequently ill children using bronchoscopic examination, enabling targeted treatment and reducing complications.

Between 2017 and 2023, 107 patients aged 2 to 15 years with prolonged and chronic cough were treated in the Thoracic Surgery Department of the Bishkek City Children's Emergency Clinical Hospital (BCCECH). These patients had previously undergone repeated, unsuccessful treatments at various pediatric healthcare facilities. After ineffective treatment, they were referred to us for bronchological examination. The Thoracic Surgery Department of BCCECH in the Kyrgyz Republic has 50 years of clinical experience in the surgical treatment of children with congenital and acquired bronchopulmonary diseases and bronchoscopic examinations.

All children underwent a detailed history collection, clinical and laboratory investigations, chest X-rays in two projections, consultation with an anesthesiologist, and, if necessary, examinations by an otolaryngologist and pediatrician. Diagnostic and therapeutic bronchoscopy was performed. Additional tests, such as blood analysis for intrauterine infections, chest CT, MRI, and pulmonary function tests, were conducted as indicated.

The age distribution of the patients was as follows: 2–4 years – 37 (34.6%), 5–10 years – 41 (38.3%), 11–15 years – 29 (27.1%). Patients from rural areas accounted for 65 (60.7%), while urban patients comprised 47 (39.3%). There were 59 boys (55.1%) and 48 girls (44.9%). The children were admitted with the following diagnoses: chronic pneumonia – 22 (20.6%), chronic bronchitis – 36 (33.6%), congenital lung anomalies – 12 (11.2%), bronchial asthma – 17 (15.9%), lung atelectasis – 11 (10.3%), and foreign body – 9 (3.4%). Comorbid conditions, such as chronic sinusitis, anemia, and biliary dyskinesia, were present in 39 (36.4%) patients. The duration of illness prior to treatment ranged from 1 to 6 years.

Upon admission, patients underwent a comprehensive clinical evaluation, with particular attention to a thorough collection of life history and complaints. This included the age of onset, whether the cough was unprovoked or followed colds and viral infections, the nature of the cough (productive or non-productive), and its relation to the child’s overall condition, choking on food, or, in older children, the habit of holding foreign objects in their mouths. Parents were able to identify the cause in only 15 (53.57%) of the patients with foreign bodies detected during bronchoscopy, as children aged 2–4 years do not always report aspiration incidents. School-aged children (4 cases) intentionally concealed information about swallowed foreign bodies due to fear of parental punishment. In 3 (10.71%) cases, even when aspiration was reported and suspected, medical personnel dismissed choking episodes, and patients were treated for suspected bronchitis or pneumonia without chest X-rays.

The history focused on the onset of the cough, with neonatal cough observed in 2 children. In one case, repeated aspiration of vomit occurred against the background of acute congenital intestinal obstruction due to Hirschsprung’s disease. The second child, admitted at 11 months, had complaints of choking and coughing during breastfeeding, receiving outpatient and inpatient treatment almost monthly at other facilities. Bronchoscopy revealed purulent-fibrinous endobronchitis in the first case and an isolated tracheoesophageal fistula in the second, which was surgically corrected, leading to recovery and discharge.

Following an objective examination and physical findings, chest X-ray images provided upon referral were reviewed, with new images in two projections taken as needed. In 62 (57.94%) children, X-rays showed changes such as enhanced bronchopulmonary patterns and fibrous strands, particularly in those with prolonged bronchitis.

Indications for bronchoscopy in children with prolonged cough include suspicion of a foreign body in the lower respiratory tract, airway anomalies, or localized changes on chest X-ray, as a normal X-ray does not rule out foreign body inhalation [3]. Many researchers have established that most aspirated objects are organic and radiopaque-negative [20,28,34]. In cases of late presentation with chronic cough, 77.1% to 87% of foreign bodies were organic [24,25,34]. Radiopaque foreign bodies in the lower respiratory tract occur in 5.8–10% of cases [28]. In 40 (41.6%) children, chest X-rays showed no direct or indirect signs of foreign bodies, and despite radiologically normal findings, bronchoscopy revealed foreign bodies in 25 (60.9%) patients [28].

Thus, a normal chest X-ray does not exclude the diagnosis of a foreign body (FB), as in the study [32], 9 out of 16 children (56.3%) had a normal chest X-ray, yet FBs were detected during bronchoscopy.

Computed tomography (CT) and magnetic resonance imaging (MRI) were used in 14 patients with significant changes on chest X-rays for differential diagnosis of suspected congenital lung anomalies or bronchiectasis. A precise image of the FB was obtained in only 4 (28.5%) cases, allowing identification of the nature and size of the FB, as well as the condition of surrounding tissues and deformation of the bronchopulmonary pattern. In 10 patients with suspected lung anomalies or bronchiectasis, findings included atelectasis, mediastinal shadow displacement, and bronchopulmonary pattern deformation. It has been reported that in 27 (55.1%) patients, multislice CT (MSCT) of the chest did not detect FBs [28]. Additionally, neither MDCT nor three-dimensional (3D) imaging identified FBs in these children, with results showing signs of pulmonary infection without atelectasis or emphysema in 25 (52.1%), enhanced pulmonary pattern in 8 (16.7%), bronchiectasis in 6.3%, and normal findings in 13 (27.1%) cases [33].

Thus, numerous studies suggest that for early diagnosis of unrecognized FBs in the lower respiratory tract and bronchopulmonary pathologies in children with prolonged and chronic cough, the most justified approach includes a detailed medical history, assessment of complaints, chest X-ray, and bronchoscopy. Prior consultation with an ENT specialist or allergist may be necessary as needed. In our cases, patients had previously been evaluated by these specialists, with 6 children undergoing ENT consultation and sinus X-rays.

Before bronchoscopy, discussions were held with parents or guardians to obtain written consent for the procedure and anesthesia. This process is one of the most challenging tasks due to the complexities of intubating a child and potential complications related not only to anesthesia but also to rigid bronchoscopy. Previously, out of 107 patients, 25 parents categorically refused bronchoscopy and general anesthesia, opting to discharge their children home. However, after several episodes of cough exacerbation, they returned to us. During discussions with parents, we used the proverb, “It’s better to see once than hear a hundred times,” or explained, “We’re standing in front of a closed door, not knowing what’s inside the room—meaning the bronchus. We’ll open the door and tell you exactly what’s there, and then we’ll treat it specifically and purposefully!” It’s also important to inform parents that “the respiratory system is the only natural pathway constantly connected to the external environment, and with every breath, dust, bacteria, particles, and more can enter the lungs alongside air.”

All bronchoscopies were performed using a rigid Karl Storz bronchoscope, selected based on the child’s age. Of the 107 patients, bronchoscopy was performed 127 times, with repeat procedures particularly conducted in cases of bilateral purulent-fibrinous endobronchitis, chronic peribronchial changes, or lung atelectasis due to prolonged FB presence. Bronchoscopic examination revealed purulent and purulent-fibrinous endobronchitis in 69 (64.5%) patients, bronchial FBs in 28 (26.7%), bronchial adenoma and tracheobronchomalacia in 4 (3.7%), and bronchiectasis in 6 (5.6%).

Among the 69 patients with chronic cough, inflammatory changes in the bronchial mucosa included catarrhal endobronchitis in 15 (21.7%) cases (all unilateral), purulent-fibrinous endobronchitis in 54 (78%) cases, with bilateral involvement in 24 (44.44%) and unilateral in 30 (55.55%). Of the unilateral cases, 21 (38.88%) were right-sided, and 9 (16.66%) were left-sided. In patients with purulent-fibrinous endobronchitis, the bronchi were thoroughly examined up to the level accessible by the bronchoscope, followed by tracheobronchial lavage with warm saline. During repeat bronchoscopies, lavage with trypsin or chymotrypsin solutions was used, particularly in cases of long-standing FBs with peribronchial changes or partial lung atelectasis, followed by lung re-expansion.

Patients with purulent-fibrinous endobronchitis experienced reduced or absent cough from the first day after diagnostic-therapeutic bronchoscopy, with cough symptoms disappearing in nearly 85% of cases by days 3–5. Of the 69 patients, only 7 had a rare dry cough without parental concern prior to discharge. Control chest X-rays before discharge showed positive dynamics in 59 (85.50%) patients, with improved lung aeration, and reduced bronchopulmonary pattern deformation in 10 (14.49%) compared to pre-bronchoscopy findings. Children with prolonged bronchitis were subsequently monitored by family physicians, and of the 69 patients, 7 returned with bronchitis exacerbation due to prior bilateral diffuse purulent-fibrinous endobronchitis. These children underwent repeat therapeutic bronchoscopy, antibiotic therapy, and physiotherapy.

Among the 28 patients with prolonged cough and FBs identified during bronchoscopy, the age distribution was as follows: under 3 years – 8 (28.57%), 3–5 years – 14 (50%), and over 6 years – 6 (21.42%). The nature of the FBs included organic materials (nut fragments, seeds, corn kernels) in 18 (64.28%) cases, non-organic items (fishing line, wheat spike, toy parts) in 7 (25%), and pen caps in 3 (10.71%). In two cases involving long-standing pen caps, bronchoscopy was performed twice due to FB fixation, following a course of antibiotics and physiotherapy. No complications occurred during bronchoscopy or FB extraction. During clinical follow-up, two patients with developing atelectasis despite repeated therapeutic interventions underwent surgical resection of the affected lung lobe.

Below are examples of bronchoscopies performed in patients who had previously received repeated treatment for chronic bronchitis at other medical facilities.

Patient M. Ch., born January 24, 2022, age 1 year. Medical record No. 4976. Admitted March 4, 2023, discharged March 14, 2023. Clinical Diagnosis: Acute focal pneumonia, prolonged course. Right-sided purulent-fibrinous endobronchitis. Complaints on Admission: Cough with sputum difficult to expectorate.

History: The illness began three months prior, with the patient receiving treatment twice. On auscultation, harsh breathing was noted in the lungs, with occasional dry and moist rales on the right side.

Laboratory Findings: Erythrocytes – 3.8 × 10¹²/L; hemoglobin – 103 g/L; leukocytes – 18.8 × 10?/L; band neutrophils – 4%; segmented neutrophils – 64%; lymphocytes – 16%; monocytes – 18%; eosinophils – 1%. ESR – 12 mm/h.

Chest X-Ray on Admission (February 29, 2024): The right lung was reduced in volume, while the left lung appeared overinflated (Figure 1a).

On March 13, 2024, a therapeutic-sanitation bronchoscopy was performed under general anesthesia. Purulent content was found in the right main bronchus and evacuated. The lavage fluid was cloudy with purulent-fibrinous content (Figure 1b). After a course of treatment, the patient was discharged in satisfactory condition with no cough. At a follow-up examination and chest X-ray one year later, no pathology was observed, and the child had no complaints (Figure 1c).

Figure 1: a – Reduced aeration in the lower-inner segment of the right lung with a slight decrease in volume, left lung overinflated; b – Lavage fluid; c – Chest X-ray one year later.

Below are examples of bronchoscopy results in patients who had previously received repeated treatment at other medical facilities, where long-standing foreign bodies in the lower respiratory tract were detected in children.

Patient T.T., age 2 years 11 months, medical record No. 2779, admitted March 15, 2017, with complaints of cough with purulent sputum and weakness.

Life History: The illness began about one year ago with a cough, followed by fever. The patient was treated multiple times on an outpatient and inpatient basis with diagnoses of acute bronchitis and bronchopneumonia. Due to the lack of treatment efficacy, the patient was referred to us for consultation. Birth history: born from the first pregnancy and delivery, birth weight 3190 g.

Examination: Percussion of the lungs revealed a pulmonary sound; auscultation showed harsh breathing with dry and moist rales in the posterior-lower segments of the right lung. Other organs showed no pathology.

Blood Analysis: Erythrocytes – 3.9 × 10¹²/L; hemoglobin – 117 g/L; leukocytes – 8.8 × 10?/L; band neutrophils – 3%; segmented neutrophils – 48%; lymphocytes – 53%; monocytes – 3%; eosinophils – 3%. ESR – 13 mm/h. ECG: Heart rate 112 beats/min, incomplete right bundle branch block. Chest X-ray: Deformation of the bronchopulmonary pattern and reduced aeration in the lower-inner part of the right lung, with a shadow of atelectasis on the right (Figure 2a).

Figure 2: (a) – Chest X-ray overview; (b) – Lavage fluid and foreign body particles.

On March 17, 2017, a therapeutic-sanitation bronchoscopy was performed. In the right intermediate bronchus, pus obstructing the lumen was found and evacuated. The bronchial mucosa was friable, and tracheobronchial lavage was conducted. Macroscopically, the lavage fluid was cloudy with purulent-fibrinous content, and particles of a foreign body were detected (Figure 2b).

Patient S.S., age 4 years 2 months, admitted September 27, 2017, Medical record No. 19579, with complaints of cough, fever, and weakness.

Medical History: The cough had persisted for over 2 years, and the patient had been treated at various medical facilities for bronchitis exacerbations. Referred with the diagnosis: “Acute left-sided pneumonia. Respiratory insufficiency, grade I. Bilateral sinusitis. Ascariasis. Biliary dyskinesia.” A detailed history revealed that approximately 2 years prior, the patient had choked on grass (a wheat spike) in a field.

Examination: Percussion of the lungs showed a pulmonary sound with shortening in the lower left segments. Auscultation revealed harsh breathing with dry rales on the right and moist rales of varying sizes on the left.

Blood Analysis: Erythrocytes – 4.0 × 10¹²/L; Hb – 123 g/L; Color index – 0.8; Leukocytes – 6.3 × 10?/L; band neutrophils – 6%; segmented neutrophils – 53%; lymphocytes – 36%; monocytes – 4%; ESR – 7 mm/h.

Chest X-Ray on Admission: In direct and lateral projections, an unclear shadow of atelectasis was observed (Figure 3a, b). Due to this, a midline tomogram of the chest was performed, revealing a distinct atelectasis shadow in the lower lobe of the left lung and an elevated left diaphragmatic dome (Figure 3c).

Figure 3: a – X-ray in anterior projection; b – X-ray in lateral projection; c – Midline tomogram.

On July 28, 2019, under general anesthesia, a bronchoscopy was performed using a Storz No. 6 tube. A foreign body (a 2 cm grass spike) was removed from the left lower lobe bronchus, with hemorrhagic lavage fluid due to peribronchial inflammation (Figure 3d).

Figure 3: d – Grass spike (top) and lavage fluid (bottom); e – X-ray before discharge.

Therapeutic-sanitation bronchoscopy was repeated twice. The X-ray before discharge showed positive dynamics (Figure 3e).

The literature describes a case of an 8-year-old girl with chronic cough persisting for 15 months before a wheat spike was found in the right lower lobe bronchus [22]. During follow-up, no complaints were reported, and control X-rays at 2 and 6 months confirmed continued improvement.

Patient B.A., age 4 years, admitted January 17, 2023, medical record No. 1768. Complaints of cough with purulent sputum.

Medical History: Ill for about 2 years, repeatedly treated on an outpatient and inpatient basis at various medical facilities with the diagnosis “Pneumonia. Aplasia of the left lung.” Outpatient chest X-ray (Figure 4a) and CT (Figure 4b) were performed, and the patient was treated multiple times for suspected “Pneumonia, left lung anomaly.”Figure 4: a – X-ray on admission; b – CT.

On January 30, 2023, under general anesthesia, a therapeutic-sanitation bronchoscopy was performed. The lower lobe bronchus was filled and obstructed with thick pus and fibrin. Thorough evacuation of bronchial contents revealed and removed a dark-colored foreign body (a toy part) (Figure 4c).

Figure 4: c – Foreign body (toy part); d – X-ray after bronchoscopy before discharge.

Control chest X-rays after foreign body removal showed persistent hypoventilation and atelectasis of the left lung (Figure 4d). Post-removal, therapeutic-sanitation bronchoscopy was performed three times. The child remained under outpatient follow-up, periodically receiving sanitation bronchoscopies and resolvent therapy to prevent bronchiectasis.

Patient K.I., age 1 year 6 months, admitted August 26, 2021, with complaints of cough, hoarseness, and elevated temperature. Born from the third pregnancy and third delivery.

Medical History: Since birth, paroxysmal cough, hoarseness, and dyspnea were noted during feeding. Locally, the patient was treated for “Bilateral aspiration pneumonia” and was registered as a frequently ill child. Condition on admission was severe due to pneumonia, with a respiratory rate of 42 breaths/min and SpO2 of 85%. Chest X-ray on August 26, 2021, showed bilateral pneumonia (Figure 5a). Esophageal contrast study on August 6, 2021, showed free passage of contrast into the stomach with no reflux into the trachea (Figure 5b).

Figure 5: a – Chest X-ray overview; b – Esophageal contrast study.

During bronchoscopy on September 9, 2021, a fistulous opening in the trachea, 0.4 × 0.5 cm, was found 1 cm above the bifurcation, with hyperemic mucosa that narrowed during inspiration.

Blood Analysis: Erythrocytes – 3.8 × 10¹²/L; hemoglobin – 116 g/L; color index – 0.9; leukocytes – 4.7 × 10?/L; ESR – 6 mm/h; band neutrophils – 4%; segmented neutrophils – 56%; eosinophils – 1%; monocytes – 3%; lymphocytes – 36%. Total protein – 66.5 g/L; albumin – 38.3 g/L; total bilirubin – 12.4 µmol/L; thymol test – 0.36 units; ALT – 21 U/L; AST – 26 U/L; urea – 4.9 mmol/L; residual nitrogen – 14.9 mmol/L; creatinine – 50.7 µmol/L.

After preoperative preparation, on September 16, 2021, surgery was performed: right thoracotomy. Upon exploration, a fistulous tract from the esophagus to the trachea, approximately 0.7 × 1.0 cm, was identified (Figure 5c). The fistula was isolated, sutured in two layers on both sides, and the tract was divided after nasogastric tube placement.

Figure 5: c – Intraoperative view of the tracheoesophageal fistula.

In the intensive care unit, the patient received antibiotics, infusion therapy, analgesics, and symptomatic treatment. The pleural drainage tube was removed on day 9, and sutures were removed on day 10. Over 12 days, the child gained 1500 g in weight. Discharged with full recovery and remains under outpatient follow-up.

A.A., age 9 years, medical record No. 2223. Admitted January 26, 2023, with a suspected bronchial foreign body. Complaints included cough with minimal sputum production and dyspnea during physical activity.

Medical History: Ill for about 4 months, treated multiple times locally with a diagnosis of right-sided pneumonia. After chest X-ray (Figure 6a), referred to us with suspicion of a bronchial foreign body. Auscultation revealed harsh breathing, with weakened breath sounds and dry rales in the lower right lung.

Blood Analysis (September 16, 2023): Erythrocytes – 5.0 × 10¹²/L; Hb – 140 g/L; color index – 0.9; leukocytes – 13.2 × 10?/L; band neutrophils – 7%; segmented neutrophils – 65%; eosinophils – 3%; monocytes – 1%; lymphocytes – 24%; ESR – 7 mm/h.

On January 28, 2023, under general anesthesia, bronchoscopy was performed. The trachea was patent; pus was found in the right intermediate bronchus and evacuated. A tumor-like mass partially obstructing the bronchial lumen was observed, bleeding diffusely upon contact with the bronchoscope tip. Tracheobronchial lavage was performed. Chest CT showed partial obstruction of the right bronchus and atelectasis of the lower lobe of the right lung (Figure 6b). The child underwent bronchoscopy twice with a flexible bronchoscope and tracheobronchial lavage. During repeat bronchoscopy, a tumor originating from the right wall of the right lower lobe bronchus was noted, broad-based, minimally mobile, and prone to easy bleeding (Figure 6c).Figure 6: a – X-ray on admission; b – Chest CT.

Figure 6c: Adenoma of the right bronchus.

Figure 6d: Chest X-ray after three bronchoscopies.

The parents declined surgical treatment due to positive X-ray dynamics following therapeutic-sanitation bronchoscopy.

In 107 frequently ill children (FIC) with prolonged and chronic cough, previously treated at various medical facilities, bronchoscopy revealed: purulent-fibrinous endobronchitis in 69 (64.48%) patients, foreign bodies in the respiratory tract in 28 (26.16%), bronchial adenoma and tracheobronchomalacia in 4 (3.73%), and bronchiectasis in 6 (5.60%) examined cases. For children with prolonged or chronic cough unresponsive to treatment, a thorough history collection and comprehensive evaluation by a pulmonologist, allergologist, immunologist, ENT specialist, and pediatric surgeon are necessary to rule out purulent-inflammatory conditions and foreign bodies in the lower respiratory tract. Following bronchoscopy, children with prolonged foreign body presence in the bronchi or purulent-fibrinous endobronchitis require repeated therapeutic-sanitation bronchoscopies and outpatient rehabilitation monitoring, which reduces long-term complications.

No conflict of interest.

Authors' Contributions

The authors participated in the analysis and design of the study, as well as in the writing and submission of the manuscript.

Acknowledgments

We would like to express our gratitude to the doctors of the pulmonology and allergology departments of the National Center for Maternal and Child Health in Bishkek for their joint work in examining children with long-term cough.

Funding Information

No financial support was received.

1. Morozov SL. Frequently ill children. A modern pediatrician's perspective. RMZh. Meditsinskoe obozrenie. 2019; 3: 7-9.
2. Xu S, Pan Z, Guo Y, Zhou Q, Wang Q, Pan S, et al. Associations between abnormal sleep behavior and indoor environmental risk factors among children with a chronic cough in Wuxi, China: a cross-sectional study. BMC Pediatr. 2024; 24: 533.
3. Chang AB, Oppenheimer JJ, Irwin RS. CHEST Expert Cough Panel. Managing chronic cough as a symptom in children and management algorithms: CHEST guideline and expert panel report. Chest. 2020; 158: 303-329.
4. Subspecialty Group of Pharmacology, Society of Pediatrics, Chinese Medical Association; National Clinical Research Center for Child Health and Disorders; Subspecialty Group of Respiratory Diseases, Society of Pediatrics, Chinese Medical Association; Children’s Respiratory Professional Committee, Society of Pediatrics of Chinese Medical Doctor Association; Editorial Board, Chinese J Pediatrics. Zhonghua Er Ke Za Zhi. 2021; 59: 720-729.
5. Baranov AA, Kozlov RS, Namazova-Baranova LS, Andreeva IV, Bakradze MD, Bulgakova VA, et al. Bronchitis: Clinical recommendations. Moscow. 2021.
6. Taranushenko TE, Falaleeva SO, Gerasimova TA. Protracted bacterial bronchitis: new aspects of the problem based on clinical recommendations of the Ministry of Health of the Russian Federation. Meditsinskiy sovet = Medical Council. 2022; 19: 61-69.
7. Marchant JM, Chang AB, Kennedy E, et al. Cough in Children and Adults: Diagnosis, Assessment and Management (CICADA). Summary of an updated position statement on chronic cough in Australia. Med J Aust. 2024; 220: 35-45.
8. Furman E, Mazunina E, Evseenkova T. Prevalence and clinical features of protracted bacterial bronchitis in children of the large Russian city of Perm. Eur Respir J. 2019; 54.
9. Shields MD, Bush A, Everard ML, McKenzie S, Primhak R. British Thoracic Society Cough Guideline Group. BTS guidelines: Recommendations for the assessment and management of cough in children. Erratum in: Thorax. 2014; 69: 303.
10. Lamas A, Ruiz de Valbuena M, Mays L. Cough in children. Arch Bronconeumol. 2014; 50: 294-300.
11. Marchant JM, Newcombe PA, Juniper EF, Sheffield JK, Stathis SL, Chang AB. What is the burden of chronic cough for families?. Chest. 2008; 134: 303-309.
12. Shields MD, Bush A, Everard ML, McKenzie S, Primhak R. Recommendations for the assessment and management of cough in children. Thorax. 2008; 63: iii1-iii15.
13. Hay AD, Heron J, Ness A. ALSPAC Study Team. The prevalence of symptoms and consultations in pre-school children in the Avon Longitudinal Study of Parents and Children (ALSPAC): a prospective cohort study. Fam Pract. 2005; 22: 367-374.
14. De Blasio F, Dicpinigaitis PV, Rubin BK, De Danieli G, Lanata L, Zanasi A. An observational study on cough in children: epidemiology, impact on quality of sleep and treatment outcome. Cough. 2012; 8: 1.
15. Waring G, Kirk S, Fallon D. The impact of chronic non-specific cough on children and their families: a narrative literature review. J Child Health Care. 2020; 24: 143-160.
16. Morice AH, Millqvist E, Bieksiene K, Birring SS, Dicpinigaitis P, Ribas CD, et al. ERS guidelines on the diagnosis and treatment of chronic cough in adults and children. Eur Respir J. 2020; 55: 1901136.
17. Chang AB, Oppenheimer JJ, Weinberger MM, Rubin BK, Grant CC, Weir K, et al. Management of children with chronic wet cough and protracted bacterial bronchitis: CHEST guideline and expert panel report. Chest. 2017; 151: 884-890.
18. Weinberger M. Chronic cough and causes in children. J Clin Med. 2023; 12: 3947.
19. Delyagin VM. Choice of therapy for coughing (spiral development). Meditsinskiy Sovet. 2019; 11: 60-66.
20. Lebedenko AA. Cough in children. The unity of theory and practice. Rostov-on-Don: Media Policy. 2014; 208.
21. Molellu MA, Mohamadian A. Diagnosis of a missed bronchial foreign body in an 8-year-old girl: a rare case report. Qatar Med J. 2021; 2021: 6.
22. Piromchai P, Lertchanaruengrit P, Vatanasapt P, Ratanaanekchai T, Thanaviratananich S. Fractured metallic tracheostomy tube in a child: a case report and review of the literature. J Med Case Reports. 2010; 4: 234.
23. Shakhnazarova MD, Sedova AY, Denisova VD, et al. Long-standing foreign body in the right bronchus of a 7-year-old girl. Meditsinskiy Sovet. 2022; 16: 122-129.
24. Karakoc F, Cakir E, Ersu R, Uyan ZS, Colak B, Karadag B, et al. Late diagnosis of foreign body aspiration in children with chronic respiratory symptoms. Int J Pediatr Otorhinolaryngol. 2007; 71: 241-246.
25. Shamsiev A, Shakhriev A, Bazarov B, Shamsieva S. The importance of new technologies in the diagnosis of non-X-ray contrast foreign bodies of the respiratory tract. J Problems of Biology and Medicine. 2013; 1: 101-104.
26. Wu Y, Dai J, Wang G, Li Y, Li H, Wu C, et al. Delayed diagnosis and surgical treatment of bronchial foreign body in children. J Pediatr Surg. 2020; 55: 1860-1865.
27. Cramer JD, Meraj T, Lavin JM, Boss EF. Object-related aspiration deaths in children and adolescents in the United States. 1968 to 2017. JAMA. 2019; 322: 2020-2022.
28. Rusetsky YY, Lokhmatov MM, Spiranskaya OA. Foreign bodies of the lower respiratory tract in children: monograph. Moscow. Information materials / Federal State Autonomous Institution "National Medical Research Center for Children's Health" of the Ministry of Health of Russia. 2019; 96.
29. Bogomilsky MR, Chistyakova VR. Pediatric otorhinolaryngology. Moscow: GEOTAR-MED. 2002; 432.
30. Saki N, Nikakhlgh S, Rahim F, Abshirini H. Foreign body aspirations in infancy: a 20-year experience. Int J Med Sci. 2009; 14: 322-328.
31. Kilikaslan O, Touren B, Ozkan A, Ak G, Temizkan RC, Kocabay K, et al. Aspiration of a foreign body in children: a survey-based study. Balykesir Medical J. 2021; 5: 144-150.
32. Moola A, Verwey C, Mabaso T, Mopeli K, Loveland J, Surg CP, et al. Tracheobronchial foreign body aspiration in children in Soweto, South Africa: a retrospective descriptive study. Afr J Thorac Crit Care Med. 2024; 30: e1145.
33. Qiu W, Wu L, Chen Z. Foreign body aspiration in children with negative multi-detector computed tomography results: own experience during 2011-2018. Int J Pediatr Otorhinolaryngol. 2019; 124: 90-93.
34. Liu B, Ding F, An Y, Li Y, Pan Z, Wang G, et al. Occult foreign body aspirations in pediatric patients: 20-years of experience. BMC Pulm Med. 2020; 20: 320.