The document discusses several congenital and acquired abnormalities of the small and large intestines. It describes Meckel's diverticulum, Hirschsprung's disease, infectious enterocolitis including rotavirus, and necrotizing enterocolitis in neonates. It also discusses malabsorption syndromes such as celiac disease, tropical sprue, and Whipple's disease. Inflammatory bowel diseases like Crohn's disease and ulcerative colitis are compared. Other topics covered include intestinal obstruction, intestinal ischemia, hemorrhoids, diverticular disease, and intestinal neoplasms.
5. iv) rectum always affected v) “short disease” involves rectum and sigmoid vi) “long disease” involves rectum and entire colon vii) male 4:1 - 10% with Down’s syndrome viii) enterocolitis, perforations with peritonitis are major causes of death www.freelivedoctor.com
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9. ii) self-limited diarrhea mostly caused by viruses c) viral gastroenteritis i) see table 17-7 ii) rotavirus - children 6-24 months - young children & debilitated adults - selectively destroys enterocytes in small intestine malabsorption, secretory and Osm diarrhea www.freelivedoctor.com
10. - peds. in hospitals and day- care centers - Ab in moms milk infections seen at time of weaning iii) adenovirus - Ad31, Ad40 & Ad41 most common diarrhea in children - malabsorption and secretory diarrhea www.freelivedoctor.com
11. iv) calicivirus - Sapporo-like (rare) - Norwalk-like (common); majority of nonbacterial food-borne epidemic gastroenteritis in all age groups v) astrovirus - 1 o children d) necrotizing enterocolitis i) neonates, premature, low birth weight (sm intest) www.freelivedoctor.com
12. Necrotizing enterocolitis (NEC). Left picture shows an abdominal X-ray of a preterm infant with NEC. The presence of gas in the wall of the intestines (“pneumatosis intestinalis”) proves the diagnosis. Right picture on the top shows multifocal necrosis of the bowel, marked by the segmental dusky, hemorrhagic appearance. The most common sites of involvement are the terminal ileum and proximal colon. Right picture on the bottom shows a distended, congested, necrotic bowel (Compare the involved segment of intestine below with the more normal segment above.) www.freelivedoctor.com
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14. Celiac disease (“celiac sprue”, “gluten sensitive enteropathy”) a) chronic disease i) T-cell inflammatory reaction with autoimmune component b) mucosal lesions i) small intestine (duod-jejunum) c) improves with removal of gluten and related grain proteins from diet (i.e., wheat, oats, barley, rye) i) CD8+ in mucosa when gluten present (IL-15 sensitive) www.freelivedoctor.com
15. d) Caucasians e) familial i) class II HLA-DQ2 or HLA- DQ8 f) clinical: i) characteristic skin blisters - dermatitis herpetiformis ii) neurologic disorders iii) Dx: - history of malabsorption - lesion present via biopsy - improve without gluten www.freelivedoctor.com
18. g) long term risk: i) NHL ii) adenocarcinoma iii) esophageal carcinoma Tropical sprue a) same characteristics as celiac b) Caribbean (not Jamaica), India, Africa, Asia c) NO specific causal agent found i) bacterial overgrowth ? - E. coli; Hemophilus www.freelivedoctor.com
19. d) injury seen at all levels of small intestine e) usually folate/B 12 deficiency f) broad spectrum antibiotics i) bacterial origin ? g) no carcinoma susceptibility Whipple disease a) rare i) bacterium - Tropheryma whippelii b) systemic condition www.freelivedoctor.com
20. Fluorescent in situ hybridisation of a small intestinal biopsy in a case of Whipple's disease (confocal laser scanning microscopy). Tropheryma whipplei rRNA is blue, nuclei of human cells are green and the intracellular cytoskeletal protein vimentin is red. Magnification approximately 200 x. www.freelivedoctor.com
21. i) affect any body part ii) mainly intestines, CNS and joints (1 o presentation) iii) small intestines: - distended macrophages - mucosal edema - lymphatic distension: lipid deposition in villi “ lipid dystrophy” iv) Caucasians; 10:1 male v) Dx = PAS+ macrophages - with rod shaped organisms www.freelivedoctor.com
22. PAS Bacilli within macrophage Arthritis (often) Steatorrhea Encephalopathy (occasionally) Malabsorption And diarrhea lymphadenopathy Lipid pools in mucosa www.freelivedoctor.com
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27. f) chronic course may lead to: i) fibrosing strictures - terminal ileum - fistulas other areas ii) protein loss iii) Vit B 12 loss iv) bile salt loss - steatorrhea v) linear serpentine ulcers www.freelivedoctor.com
28. e) extraintestinal: (altered immunity) i) polyarthritis ii) erythema nodosum iii) clubbing of fingers iv) ankylosing spondylitis v) risk of GI carcinoma - less than UC www.freelivedoctor.com
33. Patients with ulcerative colitis can occasionally have aphthous ulcers involving the tongue , lips , palate and pharynx Endoscopic image of ulcerative colitis showing loss of vascular pattern of the sigmoid colon , granularity and some friability of the mucosa . www.freelivedoctor.com
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36. c) nonocclusive ischemia i) cardiac failure ii) shock iii) vasoconstrictive drugs d) venous thrombosis i) BC pills ii) hypercoagulable states iii) peritonitis iv) invasive neoplasms v) cirrhosis vi) abdominal trauma e) other (radiation, herniation, etc.) www.freelivedoctor.com
44. Colonic diverticula are acquired herniations in which the mucosa and submucosa protrude through weak spots in the muscular layer of the colon wall. They are usually multiple (can vary from a few to hundreds) and are referred to as diverticulosis. The sigmoid colon is the location of most cases of diverticulosis (95%) , although any part of the colon can be involved. They often appear on the serosal surface in parallel rows between the teniae as seen in the gross specimen across www.freelivedoctor.com
45. Histologically, colonic diverticula have a thin wall composed of a flattened mucosa and submucosa, and a markedly attenuated and often totally absent muscularis propria layer. In most diverticula, the base of the structure consists only of a thin serosal connective tissue layer. The adjacent bowel wall surrounding diverticula shows prominent hypertrophy and thickening of the muscularis propria. www.freelivedoctor.com
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47. ii) inguinal, umbilical and scar areas - most are small bowel www.freelivedoctor.com
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49. c) malignant : i) adenocarcinoma, carcinoid, lymphomas and sarcomas ii) most in the duodenum iii) near ampulla of Vater may cause obstructive jaundice iv) obstruction major complaint - pain, cramping, nausea, vomiting, weight loss, tired (due to blood loss) v) risk from IBD (e.g., CD) and celiac disease, etc. www.freelivedoctor.com
52. Tubular adenoma of the colon. This lesion was removed with snare-electrocautery during colonoscopy. Note the stalk of normal tan mucosa and the multilobulated head of the polyp. The stalk is formed when the polyp grows to a size that allows it to be pulled on by peristaltic forces. www.freelivedoctor.com
53. ii) nonneoplastic polyps - hyperplastic (~ 95%) NO malignant potential - harmartomous (juvenile) RISK of CA - harmatomous (Peutz-Jeghers) AD genetics. Multiple scattered throughout GI tract. Melanin color around lips, face, palms. NO risk of polyp CA. Risk of intussusceptions. CA risk of breast, lungs, ovary and uterus. www.freelivedoctor.com
58. - inflammatory (“pseudo”) - lymphoid iii) adenomas - polyp types: 1.- tubular (most common) 2.- villous 3.- tubulovillous - arise from dysplasia, low grade to high grade (CA in situ) - precursor to invasive colorectal CA - slow growing (10 yrs. to 2x) www.freelivedoctor.com
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61. Familial polyposis The colon is covered in a carpet of adenomatous polyps. www.freelivedoctor.com
62. ii) further classified: - 1) attenuated - 2) Gardner syndrome - 3) Turcot syndrome 1.- attenuated a) fewer polyps (avg. ~ 30) b) most in proximal colon c) lifetime risk of CA ~ 50% www.freelivedoctor.com
63. 2. – Gardner syndrome a) # polyps same as classical FAP b) multiple osteomas i) skull, mandible and long bones c) epidermal cysts d) fibromatosis e) risk of duodenal and thyroid CA www.freelivedoctor.com
64. Dental panoramic tomogram shows a sharply defined, large radiopaque lesion consisting of several clumped toothlets on the right mandibular corpus. www.freelivedoctor.com
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69. c) environmental factors i) diet !! - immigrants from low risk CA countries coming to USA develop increased risk of CA - implicated are: 1. fiber intake 2. caloric intake vs. requirement 3. unrefined CHO 4. red meat www.freelivedoctor.com
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71. Figure 17-61 Carcinoma of the cecum. The fungating carcinoma projects into the lumen but has not caused obstruction. Figure 17-62 Carcinoma of the descending colon. This circumferential tumor has heaped-up edges and an ulcerated central portion. The arrows identify separate mucosal polyps. www.freelivedoctor.com
72. d) iron deficiency anemia in older male means GI CA until disproved ! e) metastasize to regional lymph nodes, liver, bone etc. f) Most important prognostic indicator i) extent or STAGE of tumor at time of diagnosis - TNM classification see Table 17-14 www.freelivedoctor.com
73. Figure 17-64 Pathologic staging of colorectal cancer. Staging is based on the depth of tumor invasion www.freelivedoctor.com
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75. f) can release hormones directly into circulation i) Zollinger-Ellison syndrome - gastrin from pancreatic carcinoid many peptic ulcers g) “carcinoid” syndrome (see table 17-15) i) serotonin (5-HT) and its metabolite (5-HIAA) hydroxyindoleacetic acid www.freelivedoctor.com
79. ii) MALT most common in USA - adults - no gender preference - CD5 and CD10 negative - anywhere in gut - H. pylori may be driving force (e.g., gastric MALT lymphoma) iii) IPSID (“Mediterranean lymphoma”) - B-cell (plasmacytosis) - infection plays a role www.freelivedoctor.com
80. iv) T-cell lymphoma - long term malabsorption syndrome (i.e., celiac disease) - 30-40 yrs. (10-20 yr symptoms) - proximal bowel - poor prognosis vs. B-cell www.freelivedoctor.com