MODERN CLINICAL, INSTRUMENTAL, AND MORPHOLOGICAL APPROACHES TO THE EARLY DIAGNOSIS OF HIRSCHSPRUNG DISEASE IN CHILDREN

Background. Hirschsprung disease is a congenital developmental disorder characterized by the absence of enteric ganglion cells in the distal intestine, resulting in functional intestinal obstruction. The clinical presentation of the disease depends on the length of the aganglionic segment and the age of the child and may range from acute intestinal obstruction in the neonatal period to chronic constipation in older children. In some cases, the nonspecific nature of the clinical manifestations contributes to delayed diagnosis. Objective. To analyze, based on contemporary scientific literature, the diagnostic capabilities and limitations of clinical signs, contrast enema, anorectal manometry, rectal biopsy, histochemical, and immunohistochemical examinations in the early diagnosis of Hirschsprung disease in children. Materials and Methods. A targeted narrative literature review was conducted. Priority was given to scientific studies indexed in PubMed/MEDLINE, international clinical guidelines, systematic reviews, meta-analyses, and multicenter studies. Major diagnostically relevant sources published between 2006 and 2025, as well as fundamental studies addressing the pathogenesis of the disease, were analyzed. Results. Delayed passage of meconium, abdominal distension, bilious vomiting, and persistent constipation beginning early in life are the principal clinical features that raise suspicion of Hirschsprung disease. The mean sensitivity and specificity of contrast enema are 70% and 83%, respectively, while those of anorectal manometry are 91% and 94%, respectively. In a large systematic review, rectal suction biopsy demonstrated a mean sensitivity of 96.84% and a specificity of 99.42%. Nevertheless, the reliability of biopsy findings depends on the presence of an adequate amount of submucosa in the specimen and on the quality of morphological assessment. In a recent meta-analysis of calretinin immunohistochemistry, sensitivity was 98% and specificity was 99%. Conclusion. Early diagnosis of Hirschsprung disease should not rely on a single diagnostic test but should be based on timely clinical suspicion, targeted use of instrumental diagnostic methods, and confirmation of the diagnosis through histopathological examination of a representative rectal biopsy specimen. Calretinin immunohistochemistry is an important ancillary method that improves diagnostic accuracy, particularly when conventional histological examination yields equivocal findings.