Table 1.

Timeline of symptoms and clinical course

Month	Symptoms / Progress	Management / Findings
0	Symptom onset with coughing, rhinitis similar to a mild respiratory infection Subsequently, occasionally recurring fever, cough, and rhinitis	/
+ 1 month	Development of mild feeding problems (impaired swallowing, crying when eating) as well as development of an inspiratory stridor	/
	Presentation of stridor during routine check-up with resident pediatric	- Prescription of inhalation therapy with Salbutamol - Referral to ENT for further assessment
+ 2 months	Appointment at ENT Stable condition, symptoms unchanged	- Visualization of upper laryngo-pharynx without any suspicious findings - Inability to visualize epiglottis level - Referral to ENT clinic
	Appointment at ENT hospital department Stable condition, symptoms unchanged	- Endoscopic examination of airway tract up to the epiglottis without any suspicious findings - Recommendation to continue therapy with inhalatives and corticosteroid suppositories - Recommendation for bronchoscopy
+ 3 months	Inpatient stay at our pediatric university clinic for further assessment Stable condition, symptoms unchanged	- Diagnostic bronchoscopy reveals airway obstruction, subsequent esophagoscopy shows unidentifiable FB - Chest X-ray identifies FB as button battery - First endoscopic salvage attempt, unsuccessful due to complexly lodged position - Second endoscopic salvage attempt with ENT colleagues and rigid esophagoscope, successful removal
+ 5 months	Follow-up esophagoscopy in our clinic Child in good condition but with occasional swallowing difficulties	Visualization of moderate stenosis Bougienage due to feeding difficulties
+ 6,5 months & + 8 months	Follow-up esophagoscopy in our clinic Child in good, asymptomatic condition, thriving	- Visualization of moderate stenosis - No bougienage due to asymptomatic child - biannual controls since