Part 3 GI Flashcards
What is lymphocytic colitis often seen with?
Autoimmune disorder (Celiac sprue)
What is the presentation of lymphocytic colitis?
Increased lamina propria
Chronic inflammation (plasma cells)
Increased intraepithelial lymphocytes
Surface epithelium damage
What is collagenous colitis often seen with?
Autoimmune disorder (Celiac sprue)
What is the presentation of collagenous colitis?
A band of subepithelial collagen in addition to the presentation of lymphocytic colitis
What drugs can cause drug induced enterocolitis?
NSAIDs
Chemo
Antibiotics (cause pseudomembranous colitis d/t C. diff)
What is Irritable Bowel Syndrome (IBS)?
Chronic, relapsing abdominal pain/discomfort/habits with NO known causative agent
What characterizes sigmoid diverticulitis?
Inflammation of one of the multiple diverticula in the sigmoid colon
What causes multiple diverticula to form in the sigmoid colon?
Elevated intra-luminal pressure
Exaggerated peristaltic contractions + low fiber diet –> increased intra-luminal pressure
What are the symptoms of sigmoid diverticulitis?
Usually asymptomatic, but: Lower GI bleed Lower abdominal pain Intermittent cramping Fever Change in bowel habits
An otherwise healthy young adult comes in with bloody stool, pain with defecating, and alternates between diarrhea and constipation. What is the likely diagnosis?
Solitary rectal ulcer syndrome
What is seen on microscopy of solitary rectal ulcer syndrome?
Fibromuscular hyperplasia of the lamina propria
Inflammation and ulceration
Reactive crypt hyperplasia
What is the clinical significance of an inflammatory polyp?
Associated with:
Solitary rectal ulcer syndrome
Ulcerative colitis
Crohn’s disease
What is the morphology of inflammatory polyps?
Anywhere in GI tract
Hamartomatous polyp
What is clinical difference between sporadic juvenile (retention) polyps and juvenile polyps?
Non-sporadic indicates an increased risk for GI tract adenocarcinomas…mutations in SMAD4 (TGFb pathway) and BMPRIA (a kinase)
What is the morphology of juvenile polyps?
Occurs in colon…usually rectum
Usually solitary
Hamartomatous polyp
Children < 5yo
What is the significance of Peutz-Jeghers polyps?
There is a mutation in a tumor suppressor gene (LKB1/STK11)…increased risk of CRC
What is the morphology of Peutz-Jehgers polyps?
Multiple polyps with mucocutaneous hyperpigmentation (mouth, lips, hands, genitals)
Usually in small intestine
What are the features of Peutz-Jeghers polyps?
Pedunculate polyps (long stemmed) Children present with GI bleeding and intussusception
What is the significance of hyperplastic polyps?
Usually not malignant…need to distinguish from sessile serrated adenomas and serrated adenomas
What are some things to know about hyperplastic polyps?
Most common type of adult colonic polyp…left colon/rectum
Small (<0.5cm)
Singular or multiple
What is the clinical significance of adenomatous polyps?
They are benign, but are precancerous…need to remove
What is one feature that may indicate that an adenomatous polyp is malignant?
More villous
Villous = vill-ain-ous
What are some morphological features of adenomatous polyps?
Dysplastic glandular proliferation
Usually anywhere in the colon
What is the clinical significance of sessile serrated adenoma?
Precursor to adenocarcinoma
What are some features of sessile serrated adenoma?
Attached with a flat base
Lack the adenomatous epithelium of the conventional adenoma
Found in right colon
What are the features of Familial Adenomatosis Polyposis (FAP)?
Autosomal dominant
100% risk of colorectal adenocarcinoma
Lots of polyps
Hypertrophy of retinal epithelium (might just be in Gardner’s)
What the features of Lynch syndrome?
Mutations in MMR proteins
Rarely have lots of polyps
Associated with many other cancers
What are the features of Gardner’s syndrome?
FAP + osseous and soft tissue tumors
Desmoid tumors, osteomas, epidermal cysts, dental abnormalities, thyroid tumors
What are the features of Turcot syndrome?
FAP + malignant CNS tumor
