Abnormal oral mucosal light reflectance in infantile hypertrophic pyloric stenosis

Infantile hypertrophic pyloric stenosis (IHPS) is the most common condition requiring surgical intervention during the first weeks of life. The etiology of IHPS is unknown, although both neuronal nitric oxide synthase upregulation and an extracellular matrix abnormality are suspected. Familial predisposition is an important feature. Phenotypical markers of IHPS, such as hypoplasia or agenesis of the inferior labial frenulum, have been described. The authors tested the hypothesis that IHPS is associated with abnormal reflectance of the oral mucosa.

Twenty-five children with surgically confirmed IHPS and 25 gender- and age-matched control subjects participated in the study. Reflectance of the lower gingival and vestibular oral mucosa in the optical spectrum was measured using an imaging spectrophotometer.

Patients with IHPS had significantly higher light reflectance values in the violet, blue, blue-green, green, yellow, and orange sections of the spectrum (all P values < 0.0001), with a maximum distance between group means at the 450-nm wavelength (t-value: 27.66, df = 48). A reflectance cutoff >5.26% at the 450-nm wavelength identified patients with IHPS with 100% sensitivity and 100% specificity.

This study reports a previously unrecognized mucosal reflectance abnormality of the oral mucosa in IHPS, thus offering a new, accurate, and noninvasive phenotypic marker for the condition.