A risk factor for small left colon syndrome is having a mother with diabetes.Some symptoms that may indicate an underlying disease include:
Bowel movements that contain blood. Severe abdominal bloating. Peri-anal fistula
Absent anal wink reflex
Sacral dimple
Failure to thrive

Diagnosis
The Rome process suggests a diagnosis of constipation in children fewer than 4 years old when the child has 2 or more of the following complaints for at least 1 month. For children older than 4 years, there must be 2 of these complaints for at least 2 months. 2 or fewer bowel movements per week
Passing large bowel movements
On physical exam, a doctor may find large amounts of feces within the childs rectum. A child who is already toilet trained has at least 1 accident per week involving a bowel movement. Child demonstrates withholding behavior in which he or she actively tries not to pass a bowel movement. Hard stools
Pain with defecation.For children, the degree of constipation may be scored by the Leech or the Barr systems:

The Leech system assigns a score of 0 to 5 based on the amount of feces:0: no visible feces
1: scanty feces visible
2: mild fecal loading
3: moderate fecal loading
4: severe fecal loading
5: severe fecal loading with bowel dilatation
These score are assigned separately for the right colon, the left colon and the rectosigmoid colon, resulting in a maximum score of 15.
This causes the affected portion of the colon to be unable to contract and relax to help push out a bowel movement. The affected portion of the colon remains contracted, making it difficult for stool to pass through. Concern for HD should be raised in a child who has not passed stool during the first 48 hours of life. Milder forms of HD, in which only a small portion of the colon is affected, can present later in childhood as constipation, abdominal pain, and bloating. Similar disorders to HD include anal achalasia and hypoganglionosis. In hypoganglionosis, there is a low number of neural crest cells, so the colon remains contracted. In anal achalasia, the internal anal sphincter remains contracted, making it difficult for stool to pass. However, there is a normal number of neural crest cells present.There are also congenital structural anomalies that can lead to constipation, including anterior displacement of the anus, imperforate anus, strictures, and small left colon syndrome. Anterior displacement of the anus can be diagnosed on physical exam. The disease causes constipation because the inappropriate positioning of the anus which make it difficult to pass a bowel movement. Imperforate anus is an anus that ends in a blind pouch and does not connect to the rest of the persons intestines. Small left colon syndrome is a rare disease in which the left side of the babies colon has a small diameter, which makes it difficult for stool to pass.