Each type of ARM has unique characteristics. ARM affects each child differently. Whether a child has any problems depends a great deal on the type of ARM the child has.

Below are the most common types of ARMs in children.

Boys

ARM with recto-perineal fistula: In boys, the perineum is the small area between the scrotum and the anal sphincter. This type of ARM occurs when a baby does not have a properly formed anus and the rectum ends in the perineum.

ARM with recto-bulbar fistula: In this type of ARM, the rectum connects to the urethra at the level of the lower urethra. Urine and feces mix and empty out of the urethra (the opening where urine usually exits the body).

ARM with recto-prostatic fistula: In this type of ARM, the rectum connects to the urethra at the level of the prostate (upper urethra). Urine and feces mix and empty out of the urethra.

ARM with recto-bladder neck fistula: In this type of ARM the rectum and bladder connect in a way that is not normal. This can cause urine and feces tomix and empty out of the urethra.

ARM without fistula: In this type of ARM the rectum ends in a “blind pouch.” The rectum does not connect to anything.

Girls

ARM with recto-perineal fistula: In girls, the perineum is the small area between the anal sphincter and the labia (female external genitalia). In this type of ARM the anus does not form in the normal way and the rectum ends in the perineum.

ARM with recto-vestibular fistula: In females, there is a small area between the exterior genitals (labia) and the vaginal opening. This is called the vestibule. In this type of ARM the anus does not form in the normal way, and the rectum ends in a small opening in the vestibule. This type of ARM is often misdiagnosed as a recto-vaginal fistula.

ARM with recto-vaginal fistula: In this type of ARM there is a passageway between the rectum and vagina that is not normal. As a result, gas and feces can leak into the vagina. This is a very rare type of ARM Patients often receive this diagnosis as a mis-label for a recto-vestibular fistula.

ARM without fistula: In this type of ARM the rectum ends in a “blind pouch.” The rectum does not connect to anything.

Cloaca: In this complex type of ARM, the rectum, vagina and urethra join into one common passageway and exit through one opening. Rather than having three passageways in the anorectal area (anus, vagina and urethra) the child has only one.