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What is Skip lesions are seen in: (Repeat) and explain in detail?
Ans: A (Crohn's disease) Ref: Harrison's Principles of internal Medicine, 18ed.Explanation:Crohn's diseaseMC site-terminal ileum with rectal sparing, skip areas +It is transmural, hence more of fistula formationMore of systemic symptoms, pain, abdominal massToxic megacolon- PerforationIntraabdominal abscess, fallopian tube scarring - infertilityIntestinal obstruction, massive hemorrhage, malabsorption, severe perianal diseaseCobblestoning on endoscopeResponds to antibiotics, recurs after surgeryASCA-positiveTreatment - Antibiotics, corticosteroids, sulfasalazine, mercaptopurine. azathioprine, methotrexate, cyclosporine, tacrolimusAnti-TNF: Infliximab, adalimumab, certolizumab pegolAnti-integrin: NatalizumabRisk of Ca increases with duration & severity of the disease