What Is Imperforate Anus?
Imperforate anus is a birth defect that happens while your baby
is still growing. This defect means that your baby has an improperly developed
anus. According to the Cincinnati
Children’s Hospital, about 1 out of every 5,000 babies has an imperforate
anus. It occurs more often in boys than girls. The rectum, bladder, and vagina
of a female baby with an imperforate anus typically share one large opening.
This opening is called a cloaca.
The condition develops in utero during the fifth to seventh weeks
of pregnancy. The cause is unknown. Many times, babies with this condition also
have other defects of the rectum.
Doctors usually can diagnose this condition shortly after birth.
This is a very serious condition that requires immediate treatment. Most babies
will need surgery to repair the defect. The outlook following surgery is very
What Are the Symptoms of Imperforate Anus?
The signs of imperforate anus are usually obvious soon after
birth. They include:
- no anal opening
- anal opening in the wrong place, such as too
close to the vagina
- no stool in the first 24 to 48 hours of life
- stool passing through the wrong place, such as
the urethra, vagina, scrotum, or the base of their penis
- a swollen abdomen
- an abnormal connection, or fistula, between your
baby’s rectum and their reproductive system or urinary tract
According to the Cincinnati
Children’s Hospital, about half of all babies born with imperforate anus
have additional abnormalities. Some of these may be:
- kidney and urinary tract defects
- abnormalities of the spine
- windpipe, or tracheal, defects
- esophageal defects
- defects of the arms and legs
- Down syndrome, which is a chromosomal condition
associated with cognitive delay, intellectual disability, a characteristic
facial appearance, and weak muscle ton
- Hirschsprung’s disease, which is a blockage of
the large intestine
- duodenal atresia, which is an improper
development of the first part of the small bowel
- congenital heart defects
How Is Imperforate Anus Diagnosed?
A doctor can usually diagnose imperforate anus by performing a
physical exam after birth. X-rays of the abdomen and abdominal ultrasound can
confirm the problem and reveal the extent of the abnormalities.
After diagnosing imperforate anus, your baby’s doctor should also
test for other abnormalities associated with this condition. Tests used may
- X-rays of the spine to detect bone abnormalities
- spinal ultrasound looking for abnormalities in
the vertebral body, or bones of the spine
- echocardiogram looking for cardiac anomalies
- MRI looking for evidence of esophageal defects
such as formation of fistulae with the trachea, or windpipe
What Are the Treatments for Imperforate Anus?
Imperforate anus almost always requires surgery. Multiple
procedures are sometimes necessary to correct the problem. A temporary
colostomy can also allow your baby time to grow before surgery.
For a colostomy,
your baby’s surgeon creates two small openings, or stoma, in the abdomen. They
attach the lower part of the intestines to one opening and the upper part of
the intestines to the other. A pouch attached to the outside of the body
catches waste products.
The type of corrective surgery needed will depend on the
specifics of the defect, such as how far your baby’s rectum descends, how it
affects the nearby muscles, and whether there are fistulas involved.
In a perineal anoplasty,
your baby’s surgeon closes any fistulas so that the rectum no longer attaches
to the urethra or vagina. They then create an anus in the normal positioning.
A pull-through operation is when your baby’s surgeon pulls the
rectum down and connects it to the new anus.
To prevent the anus from narrowing, it may be necessary to
stretch the anus periodically. This is called anal dilation. You may need to
repeat this periodically for a few months. Your doctor can teach you how to
perform this at home.
What Is the Long-Term Outlook?
Your doctor will instruct you on how to perform anal dilations.
These ensure that the anal opening is large enough to allow stool to pass. Some
children will experience problems with constipation. Toilet training may take a
bit longer. Stool softeners, enemas, or laxatives may be necessary to relieve
constipation later in life. Surgery can usually fix the abnormalities, and most
children do very well. A diet high in fiber and regular follow-up care
throughout childhood are helpful.