For her backed up stool, she should be investigated for following:
1) Hirschprung's disease; a barium study, stool transit time, anal manometry etc will give definite clues for it.
2) Thyroid disorders; hypothyroidism is associated with the constipation so thyroid function tests would be necessary.
3) Electrolyte problems; increased serum calcium and decreased potassium may predispose for the constipation.
4) Anorectal malformations.
Meanwhile following dietary recommendations are helpful;
1) Fruit juice - Certain fruit juices like prune, apple, or pear are beneficial. Only four to six ounces of 100 percent fruit juice per day is advised.
2) Plenty of fluids - Please do not force but 30-32 ounces (900-960 mL) or more water or other non-milk liquids per day is good.
3) Foods which are helpful: pear, strawberries, papaya, raisins, apple, sweet potato, lentils, baked potato with skin, corn, peas, lima beans, grape nuts, Kellogg's Complete Bran Flakes.
4) Avoid; cow's milk, yogurt, cheese, and ice cream.
5) Fiber supplements; wafers, chewable tablets, or powdered fiber that can be mixed in juice (or frozen into popsicles). These can be bought at health stores.
There are following medical causes of abdominal pain which need to be looked for by an Internist:
2) Adrenal disorder
3) Parathyroid disorder
4) Sickle cell disease.
5) Intestine parasites.
6) Abdominal migraines which she is being treated.
There are specific blood work which can be done by her pediatrician or an Internist.
Wish you a very happy, prosperous, healthy and safe new year 2017.
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