Some Physical Causes and Features of Constipation in Infants and Children
Cause | Common Features* | Tests |
|---|---|---|
Birth defects of the anus | ||
Abnormal position of the anus | Opening of the anus that appears closer than normal to the genitals | Measurements to determine the exact location of the anus’s opening |
Anal stenosis (a narrowed anus) | Delayed passage of the first BM (called meconium) during the first 24–48 hours of life Explosive and painful BMs A swollen abdomen Abnormal appearance or position of the anus | A doctor's examination |
Blockage of the opening of the anus (anorectal malformations) | A swollen abdomen No BMs A blockage of the anus detected during a doctor's examination | A doctor's examination done soon after birth |
Spinal cord problems | ||
Meningomyelocele (the most severe form of spina bifida) | A raw, red area on the back where the spinal cord protrudes, seen at birth A decrease in reflexes of the legs or in muscle tone Absence of the normal reflex of the anus (a tightening when lightly touched, called anal wink) | Plain x-rays of the lower spine MRI of the spine |
Occult spina bifida (incomplete formation of the bones of the spine) | Possibly a tuft of hair or dimpling on the skin over the defect, seen at birth | MRI of the spine |
A tethered spinal cord (during fetal development, the spinal cord is stuck at the lower end of the spinal column and cannot move up to its normal position) | Problems with walking, pain or weakness in the legs, and back pain Urinary incontinence | MRI of the spine |
A tumor near the tailbone (sacral teratoma) or other spinal cord tumor | Back pain, problems with walking, and pain or weakness in the legs Urinary incontinence | MRI of the spine |
Infection of the spine or spinal cord | Back pain, problems with walking, and pain or weakness in the legs Fever Urinary incontinence | MRI of the spine |
Hormonal, metabolic, or electrolyte disorders | ||
Diabetes insipidus (due to problems with antidiuretic hormone, which helps regulate the amount of water in the body) | Excessive thirst and excessive crying that is quieted by giving children water Excessive urination of dilute urine Weight loss and vomiting | Urine and blood tests to measure how dilute urine and blood are (osmolality) Blood tests to measure antidiuretic hormone levels |
Hypercalcemia (an abnormally high calcium level in the blood) | Nausea and vomiting, loss of appetite, weight loss, muscle weakness, and abdominal pain Excessive thirst and excessive urination | Blood tests to measure the calcium level |
Hypokalemia (an abnormally low potassium level in the blood) | Muscular weakness Excessive urination and dehydration Not growing as expected (failure to thrive) Possibly use of diuretics or certain antibiotics | Blood tests to measure levels of electrolytes |
Hypothyroidism (an underactive thyroid gland) | Poor feeding A slow heart rate In newborns, large soft spots (fontanelles) between the skull bones and slack muscle tone Dry skin, intolerance of cold, fatigue, and jaundice | Blood tests to measure thyroid hormone levels |
Intestinal disorders | ||
Delayed passage of the first BM Poor weight gain or failure to thrive Frequent bouts of pneumonia | A sweat test Possibly genetic testing to confirm the diagnosis | |
Delayed passage of the first BM A swollen abdomen Green or yellow vomit, indicating that it contains bile A narrowed anus detected during a doctor's examination | X-rays of the lower digestive tract after barium is inserted in the rectum (barium enema) Measurement of pressure inside the anus and rectum (manometry) Biopsy of the rectum | |
Vomiting Poor feeding Weight loss, poor growth, or both Blood in stools | Stool tests Symptoms that lessen when the formula is changed Possibly endoscopy, colonoscopy, or both | |
Abdominal pain Bloating Weight loss Fatigue | Blood tests Endoscopy | |
Long-standing (chronic) abdominal pain Diarrhea and constipation that come and go A feeling of incomplete emptying after a BM | Evaluation of BM patterns and the timing and characteristics of pain Exclusion of other disorders by history, physical examination, and possibly blood tests, stool tests, imaging, or colonoscopy | |
Pseudo-obstruction (which causes symptoms of a blockage but no blockage is detected) | Nausea and vomiting Abdominal pain and a swollen abdomen | X-ray of the abdomen Tests to assess how well the bowel functions (bowel motility studies) |
A tumor in the abdomen | Weight loss, night sweats, and fever Abdominal swelling or pain An abdominal mass detected during a doctor's examination | MRI |
Drug side effects | ||
Use of drugs with anticholinergic effects(such as antihistamines), antidepressants, chemotherapy drugs, or opioids | Use of drugs that can cause constipation | A doctor's examination |
Toxins | ||
A sudden reduction in the ability to suck Loss of muscle tone Sometimes consumption of honey before age 12 months | A test for botulinum toxin in stool | |
Usually no symptoms Possibly abdominal pain, fatigue, and irritability Regression in development | Blood tests to measure the lead level | |
* Features include symptoms and results of the doctor's examination. Features mentioned are typical but not always present. | ||
BM = bowel movement; MRI = magnetic resonance imaging. | ||