Flashcards in Gastrointestinal Pathology_2 Deck (211):
what is the morphology seen in necrotizing enterocolitis?
terminal ileum and ascending colon (gas in intestinal walls- radiology)
what are the clinical features of necrotizing enterocolitis?
mild GI disturbance or as a fulminant illness with intestinal gangrene, perforation, sepsis, shock
what is collagen EC?
when patches of band like collagen deposits under the surface epithelium, common in middle aged and older women
what is the gender prevalence of collagen EC?
what happens in lymphocytic EC?
what is the gender prevalence of lymphocytic EC?
what are the clinical features of both collagen and lymphocytic EC?
- endoscopy= normal • - radiology= unremarkable • - clinically= chronic watery diarrhea • - clinical course= benign in nature
what is another name for neutropenic colitis?
what happens in neutropenic colitis?
acute inflammatory destruction of the mucosa
what is an important cause of neutropenic colitis?
compromised blood flow
what is the site of neutropenic colitis?
what is the pathogenesis of neutropenic colitis?
impaired mucosal immunity
how dangerous is Neutropenic colitis?
what are the features of solitary rectal ulcer syndrome?
- inflammation of the rectum • - impaired relaxation and sharp angulation of the anterior rectal shelf • - inflammatory polyp
what is the characteristic triad associated with solitary rectal ulcer syndrome?
1. rectal bleeding • 2. mucus discharge from the anus • 3. superficial ulceration of the anterior rectal wall
what are the intestinal malabsorption syndromes?
celiac sprue • tropical sprue • Whipple disease • disaccharidase deficiency
malabsorption syndromes are characterized by what?
deficient absorption of fat, protein, carbohydrates, electrolytes, minerals, fat soluble vitamins, water • --> vitamin deficiency, tetani
malabsorption syndromes are caused by what?
- deficient digestion (biliary-pancreatic disease) • - deficient absorption (small intestinal disease)
what are the clinical findings in malabsorption syndromes?
weight loss • flatulence • diarrhea with bulky, frothy, greasy stools
what happens in prolonged cases of malabsorption?
anemia • petechiae • hemorrhages • dermatitis • bone aches • latent tetany • menstrual disturbance • impotence • infertility
what are the common causes of malabsorption?
celiac sprue • chronic pancreatitis • Crohn's • tropical sprue • Whipple's • bacterial overgrowth • disaccharidase deficiency • abetalipoproteinemia
what is the geographic distribution of tropical vs celiac sprue?
tropical= tropics and travelers • celiac= caucasian
what is the etiology of tropical vs celiac sprue?
1. tropical= ?infection (E coli, Hemophilus) • 2. celiac= diet: gluten--> gliadins
what is the site of involvement in tropical vs celiac sprue?
tropical= all levels of small intestine • celiac= proximal small intestine (duodenum, proximal jejunum)
what is the clinical presentation of tropical vs celiac sprue?
1. tropical= symptoms after acute diarrheal episode • 2. celiac= after gluten diet
what is the treatment for tropical vs celiac sprue?
tropical= antibiotic • celiac= gluten free diet
what is the ris of malignancy in tropical vs celiac sprue?
tropical= no risk • celiac= yes increased risk
how common is Whipple's disease?
rare systemic disease
what does Whipple's disease involve?
intestines • joints • CNS
Whipple's disease is caused by what?
Gram-positive actinomycetes Tropheryma Whippelii
who is affected by whipple's disease?
white males (M:F=10:1), 30-50yrs
what are the hallmark features of Whipple's disease?
distended macrophages in lamina propria contain PAS (+) granules • - tiny rod shaped bacilli in EM
what are the clinical features of Whipple's disease?
malabsorption syndrome • fever • joint pains • cardiac and neurologic S&S • weight loss
what is the most common presenting feature of Whipple's disease?
what is the Rx for Whipple's disease?
broad spectrum antibiotic therapy
what is disaccharidase?
apical membrane enzyme that cleaves lactose
what happens in disaccharidase deficiency?
leads to accumulation of lactose in the gut lumen, exerting an osmotic purgative effect--> diarrhea and malabsorption
what is the presentation of the congenital forms of disaccharide deficiency?
infants on exposure to milk or milk products
what is the most common presentation of disaccharide deficiency?
what are the features of the acquired form of disaccharidase deficiency?
more common • affects adults • blacks>white
what are the features of intestinal mucosa in disaccharidase deficiency?
no morphologic abnormalities
what is abetalipoproteinemia?
congenital deficiency of betalipoprotein which is required for intestinal transport of chylomicrons
what happens in abetalipoproteinemia?
the inability to synthesize apoprotein (required to assemble lipoproteins) by the enterocytes leads to accumulation of TG's in the cells, with lipid vacuolation
abetalipoproteinemia results in what?
marked lowering of serum LDL, VLDL, and chylomicrons--> defective lipid-membranes of cells (including RBC)--> acanthocytic RBC (burr cells) and widespread cell injury
how does abetalipoproteinemia present?
in infancy with malabsorption and wasting
what are the idiopathic inflammatory bowel diseases?
Crohn's disease • Ulcerative colitis
What are idiopatchic inflammatory bowel diseases characterized by?
a chronic relapsing inflammatory condition
what is the etiology of idopathic inflammatory bowel disease?
speculations as to the etiology of idopathic inflammatory bowel disease include what?
genetic factors • unknown infectious agents • special susceptibility factors • altered immuno-reactivity to dietary or infectious antigens and altered regulatory controls of the inflammatory responses
what are the 2 clinicopathologic entities into which idiopathic inflammatory bowel disease are distinguished?
Crohn's disease (CD) • Ulcerative Colitis (UC)
what is Crohn's disease?
transmural granulomatous inflammation of the bowel, with mucosal ulcerations, fissures and fistulas in young white females
skip lesions (cobblestone appearance) are characteristic of which idiopathic inflammatory bowel disease?
what are the features of UC?
crypt abscesses, pseudopolyps & increased risk of carcinoma (adenocarcinoma)
is there gross blood in the stool in UC vs CD?
UC= Yes • CD= Occasionally
is there mucus in UC vs CD?
UC= Yes • CD= Occasionally
how often are there systemic symptoms in UC vs CD?
UC= Occasionally • CD= Frequently
how often is there pain in UC vs CD?
UC= Occasionally • CD= Frequently
is there abdominal mass present in UC vs CD?
UC= rarely • CD= Yes
is there significant perineal disease in UC vs CD?
UC: no • CD: Frequently
are there fistulas in UC vs CD?
UC: No • CD: Yes
is there small intestinal obstruction in UC vs CD?
UC: no • CD: Frequently
is there colonic obstruction in UC vs CD?
UC: rarely • CD: Frequently
is there response to antibiotics in UC vs CD?
UC: no • CD: yes
is there recurrence after surgery in UC vs CD?
UC: No • CD: Yes
is there ANCA-positive result in UC vs CD?
UC: Frequently • CD: Rarely
What are the endoscopic features of Ulcerative Colitis?
1. Rectal Sparing: rarely • 2. Continuous disease: Yes • 3. Cobblestoning: No • 4. Granuloma on biopsy: No
what are the endoscopic features of Crohn's disease?
1. Rectal sparing: frequently • 2. Continuous disease: Occasionally • 3. Cobblestoning: Yes • 4. Granulomas on biopsy: Occasionally
what are the radiographic features of Ulcerative Colitis?
1. Small bowel significantly abnormal: No • 2. Abnormal terminal ileum: Occasionally • 3. Segmental Colitis: No • 4. Asymmetrical Colitis: No • 5. Stricture: Occasionally
what are the radiographic features of Crohn's disease?
1. Small bowel significantly abnormal: Yes • 2. Abnormal terminal ileum: yes • 3. Segmental Colitis: yes • 4. asymmetrical colitis: yes • 5. Stricture: frequently
what are the microscopic features of CD?
Fissuring Ulcer • Noncaseating Granuloma
what are the morphologic features of UC?
pseudopolyp • Ulcer
what are the intestinal vascular disorders?
1. ischemic bowel diseases • 2. angiodysplasia • 3. hemorrhoids
what is the extent of transmural ischemic bowel disease?
what is the extent of Mural/Mucosal ischemic bowel disease?
what is the cause of transmural ischemic bowel disease?
what is the cause of mural/mucosal ischemic bowel disease?
what types of thrombus are associated with ischemic bowel disease?
Transmural: • - arterial (common) • - venous
what vessels are associated with transmural ischemic bowel disease?
is gangrene associated with transmural ischemic bowel disease?
is gangrene associated with mural/mucosal ischemic bowel disease?
is perforation associated with transmural ischemic bowel disease?
is perforation associated with mural/mucosal ischemic bowel disease?
what is the mortality rate associated with transmural ischemic bowel disease?
what is the mortality rate associated with mural/mucosal ischemic bowel disease?
what is the differential diagnosis for transmural ischemic bowel disease?
what is the differential diagnosis for mural/mucosal ischemic bowel disease?
enterocolitis • IBD
what is angiodysplasia?
tortuous dilated submucosal veins in the cecum
angiodysplasia may cause what?
angiodysplasia occurs when?
in old age
what are hemorrhoids?
dilated varicose veins of the perianal plexus
what is the incidence of hemorrhoids?
affects 5% of adults
hemorrhoids are due to what?
chronic constipation, pregnancy, liver cirrhosis
what are the 2 types of hemorrhoids that can occur singly or together?
External • Internal
what perianal plexus is associated with internal hemorrhoids?
superior hemorrhoidal plexus
what perianal plexus is associated with external hemorrhoids?
inferior hemorrhoidal plexus
which type of hemorrhoids are painful?
what is diverticular disease?
multiple flask-like outpouchings
what is the age group affected by diverticular disease?
diverticular disease is characterized by what?
protruding into the appendices epiploicae, in the distal colon • - they are lined by mucosa but no muscularis propria
diverticular disease is caused by what?
focal anatomic defect in the bowel wall at the site of penetration of blood vessels • - increased intraluminal pressure is a contributory factor (constipation and increased peristalsis)
what are the complications of diverticular disease?
bleeding • diverticulitis • pericolic abscess • peritonitis
which pathologies involve intestinal obstruction?
hernias • adhesions • intussusceptions • volvulus
what is the most common site of intestinal obstruction?
what are hernias?
protrusion of peritoneal hernial sac into a defect in the abdominal wall (inguinal, femoral, umbilical, surgical scars, retroperitoneal space)
what happens when a hernia causes viscera to become trapped?
incarceration • obstruction • strangulation
what are adhesions?
twisting f bowel loops around peritoneal fibrous bands
what causes adhesions?
previous surgery • infection • endometriosis • radiation
what is an intussusception?
a segment of the gut telescopes into the distal one
what is the cause of intussusception?
may be caused by tumors
what is volvulus?
complete twisting of a bowel loop around its mesenteric base
what is the most common site of volvulus?
what are the two types of small intestinal tumors?
adenomas • adenocarcinomas
how common are neoplasms of the small intestine?
what is the most common benign tumor of the small intestine?
what is the most common site of benign tumor of the small intestine?
ampulla of Vater
what are the complaints associated with benign tumors of the small intestine?
occult blood loss/rarely obstruction orintussusceptions
benign tumors of the small intestine are associated with which condition?
what is the clinical course of small intestinal adenoma?
what is the most common malignant tumor of the small intestine?
what is the most common site of malignant tumor of the small intestine?
what is the clinical presentation of malignant tumors of the small intestine?
what is the only sign of small intestinal malignant tumor?
occult blood loss
what sign is present if small intestinal malignant tumor involves the ampulla of vater?
cause fluctuating obstructive jaundice
what are the risk factors associated with malignant small intestinal tumor?
most tumors - no identifiable factor • - Crohn's • - celiac • - FAP • - HNPCC • - Peutz-Jeghers syndrome
what is Peutz-Jeghers syndrome?
autosomal dominant genetic disease characterized by the development of benign hamartomatous polyps in the gastrointestinal tract and hyperpigmented macules on the lips and oral mucosa
what are the benign lower intestinal tumors?
1. onneoplastic polyps • 2. adenomas • 3. familial polyps
what are the malignant lower intestinal tumors?
1. colorectal carcinoma • 2. carcinoid tumor • 3. GI lymphoma • 4. miscellaneous tumors • 5. anal canal tumors
how common are large intestine neoplasms?
what is the most common benign tumor of the large intestine?
what is the most common site of GI polyps?
what are the types of large intestine polyps?
1. non-neoplastic: hyperplastic, inflammatory, harmtomatous • 2. neoplastic/adenomatous( tubular, villous, tubulovillus)
with what does the malignant risk of adenomatous polyps correlate?
1. polyp size (>4cm) • 2. degree of dysplasia • 3. extent of villous component (more villous= more cancerous)
what is the frequency and age associated with non-neoplastic large intestine polyps?
MC (90%) • young people • mostly hyperplastic
what is the frequency and age associated with neoplastic large intestine polyps?
only 10% • elderly people • mostly tubular
what is the level of dysplasia seen in non neoplastic large intestine polyps?
what is the level of dysplasia seen with neoplastic large intestine polyps?
what is is the mechanism that underlies non-neoplastic large intestine polyps?
production of epithelial cells exceeds their loss
what is the mechanism that underlies neoplastic large intestine polyps?
mutations in genes
what is the complication associated with non-neoplastic large intestine polyps?
no risk of malignancy
what is the complication associated with neoplastic polyps of the large intestine?
what are the types of neoplasms of the large intestine?
neoplastic or adenomatous (Tubular, Villous, Tubulo-Villous)
Are neoplasms of the large intestine true neoplasms?
Neoplasms of the large intestine cause what?
occult bleeding, anemia, protein loss, obstruction
what is FAP syndrome?
100 polyps and 100% malignant risk
what are the features of FAP syndrome?
- Autosomal dominant inheritance • - innumerable polyps (100=1000) in the colon & other parts of the GIT • - 100% risk of progression to adenocarcinoma in 10-15 years (indication for pancolectomy) • - onset in adolescence (bleeding and anemia)
What is Gardner's syndrome?
FAP syndrome associated with abnormal dentition, epidermal cysts, desmoid tumors, osteomas, duodenal and thyroid cancers
what is Turcot's syndrome?
FAP syndrome associated with CNS gliomas
how common is colorectal carcinoma?
one of the most common malignancies
what is the peak age for colorectal carcinoma?
60-70yo for sporadic cases • 30-40yo for FAP syndromes
where do colorectal carcinomas arise?
what is the etiology/pathogenesis of colorectal carcinoma related to?
1 - genetic factors • 2 - Diet: • - rich in carbs and fat • - low in veg, fruit, Vit A,C,E
what is the site of colorectal carcinoma?
what type of tumors are colorectal carcinomas?
all are invasive adenocarcinomas
what is the clinical presentation of colorectal carcinoma?
- IDA (occult bleeding) • - abdominal discomfort • - progressive bowel obstruction • - weight loss • - liver metastases
what does the prognosis of colorectal carcinoma depend on?
what is the staging system for colorectal carcinoma?
Astler-Coller modification of Duke's staging system
What are the features of Astler-Coller stage A LI tumors?
limited to mucosa
what are the features of Astler-Coller stage B1 LI tumors?
Extending to (not penetrating) muscularis propria; no LN's
what are the features of Astler Coller stage B2 LI tumors?
Penetrating the muscularis propria, but with no LN's
what are the features of Astler-Coller stage C1 LI tumors?
Extending t (not penetrating) muscularis propria + LN's
what are the features of Astler-Coller stage C2 LI tumors?
penetrating through muscularis propria + LN's
what are the features of Astler Coller stage D LI tumors?
distant metastatic spread
what is the only hope for cure of LI tumors?
what is the prognosis for Astler Coller stage A LI tumors?
what is the prognosis for Astler-Coller stage B1 LI tumors?
what is the prognosis for Astler-Coller stage C1 LI tumors?
what is the prognosis for Astler- Coller stage C2 LI tumors?
what is the most common site of carcinoid Gi tumors?
what fraction of small intestinal malignancies are carcinoid tumors?
what is the peak age for carcinoid tumors?
what do carcinoid tumors do?
arise from neuroendocrine cells and secrete active amines or peptides
what happens with a carcinoid tumor secretes gastrin?
what happens when a carcinoid secretes insulin?
what happens when a carcinoid secretes ACTH?
what happens when a carcinoid secretes serotonin?
how often do appendiceal and rectal carcinoids metastasize?
how often do ileal, gastric & colonic carcinoids metastasize?
what is the prognosis for carcinoid GI tumors?
5 years: • - 90% without mets • - 50% with mets
What is the implication for carcinoid tumor with liver mets?
will develop carcinoid syndrome
what are the pathologies of the appendix?
acute appendicitis • tumors
in what age group is acute appendicitis most common?
adolescents and young adults
acute appendicitis is characterized by what?
1. obstruction of lumen • 2. raised intraluminal pressure • 3. Ischemic injury and bacterial invasion
what is the morphology of acute suppurative appendicitis?
hyperemia • edema • PML infiltration of all layers of all layers of the wall to the peritoneum
what is the morphology of acute gangrenous appendicitis?
thrombosis of appendicular vessels--> gangrene--> diffuse septic peritonitis
what is the morphology of localized or generalized peritonitis?
when the peritoneum becomes covered by fibrino-purulent exudate
what is notable about the clinical features of acute appendicitis in old age?
what are the complications associated with acute appendicitis?
perforation • pylephlebitis • liver abscess
what are the 3 types of tumor of the appendix?
1. mucocele • 2. carcinoid • 3. carcinoma
mucocele of the appendix is characterized by what?
distension of the appendiceal lumen by mucinous secretion
what is the non-neoplastic cause of mucocele of the appendix?
what is the benign neoplastic cause of mucocele of the appendix?
what is the malignant neoplastic cause of mucocele of the appendix?
mucinous cystadenocarcinoma (fatal)
what are the complications of mucinous cystadenocarcinoma of the appendix?
may rupture--> peritoneal implants--> produce pseudomyxoma peritonei
what is the most common tumor of the appendix?
are carcinoid tumors of the appendix malignant or benign?
almost always benign and discovered accidentally on appendectomy (curative)
what are the features of carcinoma of the appendix?
adenocarcinomas, identical to their intestinal counterparts
what are the types of peritonitis?
1. sterile peritonitis • 2. septic peritonitis • 3. sclerosing retroperitonitis
what causes sterile peritonitis?
1. chemical irritation by bile, pancreatic juice, endometriosis (blood) • 2. ruptured ovarian cyst (dermoid) • 3. introduction of chemical substances for diagnostic (laparoscopy, salpingography) or therapeutic procedures (peritoneal dialysis)
what causes septic peritonitis?
bacterial infection of the peritoneum from: • - acute appendicitis • - ruptured PU • - acute cholecystitis • - diverticulitis • - bowel strangulation • - acute salpingitis • - evacuation of ascitic fluid • - peritoneal dialysis
what is the clinical course of septic peritonitis?
localized (loculated abscesses) and may heal by fibrous adhesions--> chronic obstruction
what are the potential causes of idiopathic sclerosing retroperitonitis?
- may be related to anti-migraine drugs (methysergide) • - may be autoimmune
sclerosing retroperitonitis is characterized by what?
excessive fibrous tissue proliferation (fibromatosis)
what are the complications associated with sclerosing retroperitonitis?
compromising retroperitoneal structures
what happens when ureters are compromised by sclerosing retroperitonitis?
what is the cause of mesenteric cysts?
blocked lymphatics • enteric diverticula • postinfectious cysts • postpancreatitis pseudocysts • neoplastic cysts
how common are primary peritoneal tumors?
what is an example of primary peritoneal tumor and its cause?
mesothelioma= related to past asbestos exposure, identical to its counterpart in the pleura
how common are secondary peritoneal tumors?
where do secondary peritoneal tumors come from?
advanced cancer of any abdominal viscera: • stomach, colon, small intestine, pancreas, liver, gallbladder, uterus, breast
in secondary peritoneal tumor, diffuse seeding of the peritoneal cavity leads to what?
malignant effusions (mainly ovarian)