What is Organic causes of constipation in infant are all except –a)  High fibre dietb)  Cystic fibrosisc)  Hypothyroidismd)  Hyperthyroidism and explain in detail?
Constipation in infants and children
Constipation is extremely common in pediatric population. The vast majority of cases (90-95%) are functional i.e. 90-95% have functional constipation with no organic disease. In 1-5% cases, the organic disease can be diagnosed as cause of constipation, i.e. only 1-5% have organic causes of constipation.
Organic causes of constipation are:

Intestinal: Hirschprung disease, Anal/rectal stenosis, Anal fissure, anteriorly displaced anal opening, stric­tures.
Drugs: Narcotics, vincristine, Psychotropics.
Metabolic/endocrine: Cystic fibrosis, hypothyroidism, Panhypopituitrism.
Neuromuscular: Cerebral palsy, Psychomotor retardation, spinal cord lesions, Myotonic dystophy, Neuropathy or myopathy of GIT.
Other causes: Low fibre diet, Milk protein allergy.