Is UACS Common Among Babies?
No, Upper Airway Cough Syndrome (UACS) is not common in babies and infants—it is primarily a condition seen in older children and adults. 1
Evidence from Pediatric Chronic Cough Studies
The 2017 CHEST guideline systematically reviewed chronic cough etiologies across pediatric age groups and found that UACS accounted for only 20% of cases in one mixed-age pediatric cohort, and was notably absent or rare in studies focusing on younger children. 1
Age-Specific Patterns in Chronic Cough
In infants and young children, the most common causes of chronic cough are protracted bacterial bronchitis (PBB) at 41%, asthma/asthma-like conditions at 16-25%, and natural resolution without specific diagnosis at 14-22%. 1
UACS was only identified as a common etiology in two Turkish studies that included older children (mean ages 5-8 years), not infants. 1
Studies specifically examining infants under 2 years showed no significant representation of UACS as a diagnostic category. 1
Why UACS is Uncommon in Babies
Anatomical and Physiological Differences
Infants have fundamentally different upper airway anatomy that makes the adult/older child pattern of UACS unlikely:
Newborns are obligate nasal breathers until 2-6 months of age, with nasal passages contributing 50% of total airway resistance. 1, 2
Any nasal congestion in infants below 2-6 months can create near-total airway obstruction and potential respiratory failure, rather than the postnasal drip pattern seen in UACS. 1, 2
Different Diagnostic Considerations in Babies
When babies present with upper airway symptoms, the differential diagnosis is entirely different from UACS:
Viral upper respiratory infections are the most common cause of nasal congestion and respiratory symptoms in infants. 2
Laryngopharyngeal reflux (LPR) produces nasal congestion through inflammation and narrowing of the posterior choanae, presenting with choking, apneic spells, and aspiration—not the classic UACS pattern. 1, 2
Anatomic abnormalities such as choanal atresia, nasal septal deviation, or adenoidal hypertrophy are more relevant considerations than UACS in this age group. 1, 2
Congenital upper airway obstruction from structural problems requires early recognition to avoid hypoxia-related complications. 3, 4
Critical Clinical Pitfalls
Do not apply adult UACS diagnostic criteria to infants. The classic UACS symptoms—sensation of postnasal drip, throat clearing, cobblestoning of posterior pharynx—are not reliably identifiable or relevant in preverbal infants. 1
Approximately 20% of adult patients with UACS are unaware of postnasal drainage, making clinical diagnosis challenging even in verbal patients. 1 This diagnostic approach is essentially impossible in infants who cannot report symptoms.
In babies with respiratory symptoms, prioritize evaluation for:
- Respiratory distress signs (retractions, nasal flaring, grunting) that indicate severity and potential need for hospitalization 2, 5
- Feeding difficulties, choking, or apneic spells suggesting aspiration or LPR 1, 2
- Unilateral vs. bilateral obstruction to identify anatomic abnormalities 2
The narrow therapeutic window in infants makes empiric treatment with antihistamine/decongestant combinations (standard UACS therapy in older patients) extremely dangerous. 2 OTC cough and cold medications should be avoided in all children below 6 years due to documented fatalities. 2