Evolution of filiform polyposis from classical pseudopolyposis in a pediatric ulcerative colitis patient

Area of Science:

• Gastroenterology
• Pediatric Gastroenterology
• Colorectal Diseases

Background:

• Filiform polyposis (FP) is a rare morphologic variant of pseudopolyposis.
• It is associated with inflammatory bowel disease (IBD), including ulcerative colitis (UC).
• Pediatric cases of FP are infrequently reported in medical literature.

Observation:

• This report details a pediatric patient diagnosed with UC at age 7.
• Initial colonoscopy revealed classical pseudopolyposis during an acute UC flare.
• A subsequent colonoscopy at age 9 demonstrated the transformation of pseudopolyps into FP.

Findings:

• The patient achieved clinical remission with sulfasalazine monotherapy.
• Remission was confirmed by zero scores on the pediatric UC activity index and normal inflammatory markers.
• Surveillance colonoscopy at age 14 confirmed persistent, diffuse FP in a healthy colonic mucosa background, despite clinical remission.

Implications:

• This case highlights the potential evolution of classical pseudopolyps to FP in pediatric UC.
• It documents FP development in an asymptomatic child in clinical remission.
• The findings contribute to understanding FP's natural history in pediatric IBD.