A 2-day-old full-term neonate is evaluated in the nursery for failure to pass meconium and progressive abdominal distension. Physical examination reveals a remarkably tight anal sphincter. Upon withdrawal of the examiner's finger during a digital rectal examination, there is an explosive release of gas and foul-smelling stool. Arrange the following steps in the optimal diagnostic and therapeutic sequence for this patient's suspected condition.
- 1Obtain a plain abdominal radiograph
- 2Perform a lower gastrointestinal contrast enema
- 3Obtain a rectal suction biopsy
- 4Perform a surgical pull-through procedure
Answer
The correct sequence is to first obtain a plain abdominal radiograph, followed by a contrast enema, then a rectal suction biopsy, and finally a surgical pull-through procedure.
The patient's presentation of delayed meconium passage, progressive abdominal distension, and an explosive release of stool upon rectal examination (the 'squirt sign') is highly characteristic of Hirschsprung disease. The standard sequence of management begins with a plain abdominal radiograph to assess for dilated loops of bowel and rule out perforation. Next, a contrast enema is performed to visualize the anatomy and identify a transition zone. Following these imaging studies, a rectal suction biopsy is required to definitively confirm the diagnosis by demonstrating an absence of ganglion cells. Finally, definitive treatment is surgical resection of the aganglionic bowel through a pull-through procedure.
Step-by-Step Solution
Key Concept
Diagnosis and management sequence for Hirschsprung disease in a neonate.