Introduction. With an increased frequency and a seemingly benign clinic, the disorders of bowel transit and evacuation are considered by most parents and even doctors as a "trivial" biological phenomenon and, unfortunately, is neglected. Chronic, long-term evolution of the disease slowly causes dysbacteriosis, obstructive enterocolitis, endotoxicosis, secondary changes of the colon, etc. Case presentation: We present the case of a 5-year-old girl, who suffers from constipation since neonate. In the dynamics, the constipation acquired a chronic character with abdominal pain, difficulties of bowel evacuation, formation of the impacted feces and soiling. All the symptoms of functional decompensation forced the parents to consult the doctors: pediatrician, neuropsychologist, endocrinologist. Formulating the diagnosis without performing a complex examination and argumentation of the etiopathogenesis of the disease indicated a symptomatic treatment, without effectiveness, which prompted the visit to the surgeon with the following complaints: constipation with bowel obstruction, soiling, flatulence. Discussion. The patient underwent the subsequent examinations: profilometry of anal canal, ampulotonometry with balloon expulsion test, electromyography of external anal sphincter, histomorphological investigation of full-thickness rectal biopsy. The result was diagnosed as a combined congenital anomaly of the colon: dimensional deviation. Conclusion. Early objective diagnosis of anatomo-topographic malformations of the colon, with subsequent radical treatment has a major socio-economic value by reducing the duration of palliative preoperative treatment; decrease the rate of secondary complications; reducing the complexity of surgery; diminution of the rate of postoperative functional disabilities and respectively of the duration of the postop functional recovery period.