Pediatric Intestinal Pseudo-obstruction in the Era of Genetic Sequencing.

PURPOSE OF REVIEW: The purpose of this review is to discuss current knowledge on pediatric intestinal pseudo-obstruction. We will also review new mutations that have been identified through advancement in genetic testing, allowing for a better understanding of the underlying mechanisms of intestinal dysmotility and potential etiologies. RECENT
FINDINGS: With the advancements in genetic testing, new mutations have been identified in the diagnosis of megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS), a disorder leading to pediatric pseudo-obstruction. MYLK, LMOD1, MYL9, and MYH11 encode for various proteins within smooth muscle cells; abnormalities within these proteins lead to abnormal intestinal smooth muscle contractions. Chronic intestinal pseudo-obstruction (CIPO) is defined by symptoms of bowel obstruction in the absence of a lumen-occluding lesion. CIPO is a heterogeneous group of disorders caused by abnormalities in the enteric neurons, intestinal smooth muscle, and/or the interstitial cells of Cajal (ICC). Symptoms can be non-specific and etiologies include both primary and secondary causes of CIPO that contribute to the delay in recognizing this condition and making the correct diagnosis. Chronic intestinal pseudo-obstruction has been recognized in both adults and children with fundamental differences in the etiology, symptom onset, clinical features and natural history of this disorder. For this reason, it has been considered a separate entity referred to as pediatric intestinal pseudo-obstruction (PIPO).