Common Pediatric Surgical ConditionsDr. Hatem El GoharyLecturer of General Surgery MD, MRCS

Hirschsprung Disease

Definition

Developmental disorder of the enteric nervous system and is characterized by an absence of ganglion cells in the distal colon resulting in a

functional obstruction[.

Aetiology

Innervation of the colon: • Extrinsic: Mainly lead to Increase in smooth muscle tone.• Interinsic: Relaxation of the colon.

• Congenital aganglionosis of the distal bowel

• Both the myenteric (Auerbach) plexus and the submucosal (Meissner) plexus are absent, resulting in reduced bowel peristalsis and function.

Diagnosis

Symptoms:• Newborn with delayed passage of meconium.• Chronic constipation• Vomiting, Distention, poor feeding, and failure to thrive.

Signs:• Distended abdomen. • Spasm of the anus.

Investigations

1 -Barium enema Narrowed distal colonProximal dilationTransition zone

2 -Full Thickness rectal biopsy Aganglionosis

TREATMENT

• Rehydration and Nasogastric tube.• Diverting colostomy at the time of diagnosis. Then• Swenson procedure : Resection of the aganglionic

segment and oblique anastomosis of the colon.

• Duhamel procedure Resection of the aganglionic segment and end to side anastomosis of the colon.

IMPERFORATE ANUS

Embryology

• The rectum and anus are believed to develop from the dorsal potion of cloacal cavity,

• Downgrowth of the urorectal septum is believed to close this duct by 7 weeks' gestation.

• This septum separates the rectum and anal canal dorsally from the bladder and urethra.

Aetiology

Defects in the formation or shape of the posterior urorectal septum.

Types

• A low lesion, in which the colon remains close to the skin.

• A high lesion, in which the colon is higher up in the pelvis.

• A persistent cloaca , in which the rectum, vagina and urinary tract are joined into a single channel.

Diagnosis

• Identified upon the first physical examination.• Failure to pass meconium within 24 hours.

• X-Ray Lateral view Upside down.

< 1cm …low> 1cm …high

Common Association

VACTERLVertebral anomaliesAnorectal (e.g.imperforate anus)Cardiac

Tracheal (e.g.fistula)EosophegealRenalLimb

Treatment

< 1 cm Primary neonatal pull-through.

> 1 cm Colostomy Then Pull - through.