How is it Diagnosed?
Anorectal Malformation (ARM) refers to a spectrum of congenital defects involving the
anus and rectum. Diagnosis typically begins at birth with a physical examination.
Newborns with ARM may present with absent or abnormally located anal openings, or
signs of bowel obstruction such as abdominal distension, vomiting, or failure to pass
meconium within the first 24 hours.
Initial evaluation involves inspection of the perineum to check for the presence, location,
and patency of the anal opening. In male infants, a fistula may open into the urethra,
while in females, it may be into the vestibule or vagina.
To determine the level and type of malformation, imaging studies are essential. An
invertogram (cross-table lateral X-ray) is commonly performed 12 to 24 hours after birth
to assess the distance between the rectal pouch and the perineal skin. Ultrasound of
the abdomen and pelvis helps detect associated anomalies, particularly of the urinary
tract and spine. MRI or distal colostogram may be needed for detailed anatomy before
surgical planning.
ARM is often associated with other congenital anomalies, especially those falling under
the VACTERL association (Vertebral, Anorectal, Cardiac, Tracheoesophageal, Renal, and
Limb anomalies). Therefore, a thorough systemic examination and echocardiography,
renal ultrasound, and spinal imaging are standard.
Timely diagnosis enables planning for surgical intervention, which may involve primary
repair or staged surgery. Multidisciplinary evaluation is crucial for optimal outcomes.