Anorectal emergencies

Table 3 Common anorectal disorders presenting with delay or failure to pass meconium in the neonates

Diagnosis	Rate	Common physical findings	Suggested investigation: expected findings	Initial management
Meconium plug syndrome	1/500-1000	Abdominal distension, normal anus and anal sphincter complex	Contrast enema radiologic examination: meconium plug in colon	Rectal stimulation with finger or saline enema
Hirschsprung’s disease	1/4000	Abdominal distension, tight anal sphincter, empty rectum, sudden evacuation of stool on digital rectal examination if “transitional zone” is reached	Contrast enema radiologic examination without colonic preparation: transitional zone separating aganglionic segment and dilated proximal colon	Intravenous hydration, gastric decompression, rectal washout with warm saline, and consider colostomy in high-grade obstruction and intravenous board-spectrum antibiotics in those with suspected diagnosis of Hirschprung-associated enterocolitis
Imperforate anus (IA)	1/5000	Absence or stenosis of anus, perineal fistula (low IA), meconium in urine (rectourinary fistula: low or high IA), flat or not well formed median raphe (high IA), cloaca (high IA), VACTERL anomalies1	Inverted lateral radiography (invertography) or transperineal ultrasonography: differentiation between low IA and high IA	Anal or fistula dilatation for temporary relief of obstruction and plan for elective posterior sagittal anorectoplasty (low IA), loop sigmoid colostomy (high IA or some low IA)
- Low IA = distal rectal pouch lining below or at the puborectalis muscle
- High IA = distal rectal pouch lining above the puborectalis muscle

¹VACTERL anomalies include vertebral anomalies (V), anorectal malformations (A), congenital cardiac anomalies (C), tracheoesophageal fistula or esophageal atresia (TE), renal and urinary anomalies (R), limb lesions (L).