Pathoma - 10 (GI)

eliot2014's version from 2016-01-27 19:51

Section 1

Question Answer
Whats the triad of Behcet syndrome?recurrent mouth (aphthous) ulcers, genital ulcers and UVEITIS
What causes Behcet?immune complex vasculitis involving small vessels (may be seen after viral infection but etiology is unknown)
What is an aphthous ulcer?pain, superficial ulceration of the oral mucosa
What causes aphthous ulcers?stress
How is an aphthous ulcer characterized?grayish base (granulation tissue) surrounded by erythema
What can reactivate oral herpes?stress and sunlight
Difference between leukoplakia, oral candidiasis and hairy leukoplakialeukoplakia=white plaque that cannot be scraped away (it represents squamous dysplasia) oral candidiasis=white deposit on tongue which is easily scraped away hairy leukoplakia=white rough patch on lateral tongue (EBV induced squamous hyperplasia)
What is erythroplakia?vascularized leukoplakia
Whats the most common location for ORAL/mouth squamous cell carcinoma?floor of the mouth
What 2 risk factors for oral squamous cell carcinoma?tobacco and alcohol
what is the classic precursor lesion of oral squamous cell carcinoma?oral leukoplakia and erythroplakia
what is oral leukoplakiasquamous cell dysplasia! white plaque that cant be scraped away
what causes hairy leukoplakia?EBV-induced squamous HYPERPLASIA = NOT premalignant!!! no risk for cancer

Section 2

Question Answer
pt presents with BL parotiditis, orchitis, pancreatitis and meningitisMUMPS!!!
what is sialadenitis?inflammation of salivary gland (usually unilateral)
Most common cause of sialadenitis?sialolithiasis (obstructing stone) leading to s. aureus infection
What kinds of glands are salivary glands?exocrine
What are the three major salivary glands?parotid, submandibular, and sublingual
Why do you see an increase in serum amylase from mumps?salivary gland AND/OR pancreatic involvement
Whats the most common tumor of the salivary gland?pleomorphic adenoma
What tissue is pleomorphic adenoma composed of?stromal (cartilage) and epithelial tissue
pt presents with painlesss, mobile, circumscribed mass at the ANGLE OF THE JAWpleomorphic adenoma
Why is pleomorphic adenoma painless?because it hasn't invaded the facial nerve (
how do you know if a pleomorphic adenoma has turned into a carcinoma?presents with signs of facial nerve damage (e.g. palsy)
Does pleomorphic adenoma have a high or low rate of recurrence?high
what nerve runs through but does not innervate the parotid gland?CN VII = facial nerve
benign cystic tumor with abundant lymphocytes and germinal centers in parotid glandWARTHIN TUMOR
What is the second most common tumor of the salivary gland?warthin tumor
Where do warthin tumor like to arise?parotid (parotid is one of the last gland to separate itself from the adjacent stroma embryologically--it is common to see lymph node tissue is parotid)
What types of cells are in a mucoepidermoid carcinoma?mucinous and squamous cells
Describe a warthin tumor histologicallycystic tumor with abundant lymphocytes and germinal centers (lymph node-like stroma)
whats the most common malignant tumor of the salivary gland?mucoepidermoid carcinoma = arises in parotid and involves facial nerve

Section 3

Question Answer
what protrudes in esophageal web?only esophageal MUCOSA in the upper esophagus
What is the most common form of tracheoesophageal fistula?proximal esophageal atresia with the distal esophagus arising from the trachea
Presentation of tracheoesophageal fistulavomiting, polyhydramnios, abdominal distension, and aspiration
Presentation of esophageal webdysphagia for poorly chewed food
what carcinoma is associated with esophageal webs?esophageal squamous cell carcinoma
Plummer Vinson syndromesevere iron deficiency anemia, esophageal web, and beefy-red tongue due to atrophic glossitis
zenkers diverticulum: true or false diverticulum?FALSE diverticulum = outpouching of MUCOSAL layer only
location of zenker's diverticulumabove the upper esophageal sphincter at the junction of the esophagus and pharynx
Presentation of Zenker diverticulumdysphagia, obstruction, and halitosis (bad breath--food gets trapped in diverticulum)
What is Mallory-Weiss?Longitudinal laceration of mucosa at the gastroesophageal junction
Presentation of mallory-Weiss?painful hematemesis
whats a feared complication of mallory weiss syndrome?Boerhaave syndrome = rupture of eosphagus leading to air in the mediastinum and subcuteanous emphysema (air bubbles beneath skin)
What are esophageal varices?dilated submucosal veins in the lower esophagus
Drainage of the esophageal veinesophageal vein-->left gastric vein-->portal vein
Presentation of esophageal varicesPainless hematemesis
What is the most common cause of death in cirrhosis?esophageal varices
damage to which cells causes achalasia?damaged ganglion cells in myenteric plexus (these cells are located btw inner circular and outer longitudinal layers of musclaris propria)
What is the function of ganglion cells in myenteric plexus?regulate bowel motility and relax LES
What is achalasiadisordered esophageal motility with inability to relax the LES
What is one infection that can cause achalasia?Trypanosoma cruzi
pts with achlasia are at an increased risk for which carcinomaesophageal squamous cell carcinoma
Clinical featurs of achalasiadysphagia for solids and liquids (due to lack of motility), putrid breath (food piles up in esophagus), high LES pressue on esophageal manometry, bird beak sign on barium swallow study
If you hear bowel sounds in the lower lung field...what does that suggest?paraesophageal hernia (may also have lung hypoplasia)
Risk factors for GERDalcohol, tobacco, obesity, fat rich diet, caffeine, and hiatal hernia
What type of hernia increases the risk for GERDsliding hernia (Stomach herniates into esophagus--LES tone is normal)
What is the progression of metaplasia due to GERD?Non-keratinizing squamous epithelium turns into non-ciliated columnar cells with goblet cells
Clinical features of GERDheartburn (mimics cardiac chest pain), adult onset asthma and cough, damage to tooth enamel, ulceration with stricture and Barrett esophagus occur later (ulceration-->knock out mucosa and some part of submucosa. If the stem cells are knocked out, healing will be via fibrosis-->lumen will be narrowed)
cancer involving lower 1/3 of esophagusesophageal adenocarcinoma
What is the most common esophageal carcinoma in the west?adenocarcinoma
What is the most common esophageal cancer worldwide?squamous cell carcinoma
Risk factors for squamous cell carcinoma of esophagusalcohol and tobacco (most common causes), very hot tea (southern China and India), achalasia, esophageal web, esophageal injury (e.g. lye)
Symptoms of esophageal carcinomaprogressive dysphagia (solids first, then liquids), weight loss, pain, hematemesis (tumor grows and stretches mucosa, causing bleeding). SCC may additionally present with voice hoarseness (due to involvement of recurrent laryngeal nerve) and cough (due to tracheal involvement)
What carcinoma arises from Barrett esophagus?adenomcarcinoma
cancer involving upper 2/3 of esophagusesophageal squamous cell carcinoma
protrusion of mucosal layer in the esophagusesophageal webs
upper 1/3 of esophagus spreads to which LNs?cervical LNs
middle 1/3 of esophagus spreads to which LNs?mediastinal or tracheobronchial nodes
lower 1/3 of esophagus spreads to which LNs?celiac and gastric nodes

Section 4

Question Answer
What causes omphalocele?failure of herniated intestine to return to the body cavity during development (normally they turn 90 degrees and return to the body cavity)
How do you distinguish between gastroschisis and omphalocele?omphalocele=contents are covered by peritoneum and amnion of the umbilical cord. gastroschisis=not covered by anything
What is pyloric stenosiscongenital hypertrophy of pyloric smooth muscle
What group more commonly has pyloric stenosis?males
when does pyloric stenosis present?2 weeks after birth = takes 2 weeks for stenosis to develop
Clinical presentation of pyloric stenosisprojectile nonbilious vomiting, visible peristalsis, olive-like mass in abdomen (due to stenotic pyloric sphincter)
How do you treat pyloric stenosis?myotomy
What is acute gastritis?acidic damage to the stomach mucosa
What causes acute gastritisimbalance between mucosal defenses and acidic environment
what are risk factors for acute gastritissevere burn (curling ulcer); NSAIDS ; alcohol; chemotherapy; Cushing ulcer; shock
Erosion vs. Ulcererosion=loss of superficial epithelium. Ulcer=loss of mucosal layer.
whats a HY risk factor for acute gastritis?increased ICP (cushing ulcer) = increased vagal nerve stimulation leads to increased acid production (increased ACh --> increased acid production)
what are the 2 types of chronic gastritis?autoimmune gastritis and H.pylori gastritis
what HSN is chronic autoimmune gastritis?Type IV (mediated by T-cells)
Where are parietal cells locatedbody and fundus of stomach
autoimmune gastritis is at increased risk for which cancer?gastric adenocarcinoma - intestinal type
pt presents with achlorhyridia with increased gastrin levels and antral G-cell hyperplasia (G-cells make gastrin)chronic autoimmune gastritis
whats the most common site for H.pylori gastritis?ANTRUM of stomach (lowest part)
what causes duodenal ulcers?H.pylori!!
which glands are hypertrophied in peptic ulcers and why?brunner gland hypertrophy = these glands secrete mucus
are duodenal ulcers maligannt?nope! never malignant!
having blood type A is a/w which carcinoma?gastric carcinoma - intestinal type
signet ring cells that infiltrate the gastric walldiffuse type gastric carcinoma
which gastric carcinoma is NOT associated with H.pylori, intestinal mucosa or nitrosamines?Diffuse type gastric carcinoma!!!
what are some places gastric carcinoma likes to spread to?Left supraclavicular node (virchrow node)
Periumbiical node (intestinal-type)
BL ovaries (diffuse type)
which carcinoma likes to spread to BL ovaries (kruckenberg tumors)diffuse type gastric carcinoma

Section 5

Question Answer
double bubble signduodenal atresia OR annular pancreas
persistence of vitelline duct (connects yolk sac to small bowel)meckels diverticulum
baby passes meconium thru umbilicus?meckels diverticulum = failure of vitelline duct to involute
outpouching of all 3 layers of bowel wallmeckels diverticulum = TRUE diverticulum
whats the leading edge causing intussusception in kids?lymphoid hyperplasia due to rotavirus --> arises in ileum leading to intussception into cecum
name 2 things that cause small bowel transmural infarctionthrombosis/embolism of SMA or thrombosis of mesenteric vein
what location is affected most in Celiac Disease?DUODENUM
HLA-DQ2 and HLA-DQ8celiac disease
which cell mediates tissue damage in CELIAC DISEASE?helper T-cell = gliadin is presented by APC via MHC class II --> helper T cell mediate damage
what causes dermatitis herpetiformis?IgA deposition on tips of dermal papilae
IgA antibodies against endomysium and tTGceliac disease
name 2 very HY late complications of refractory celiac disease?small bowel carcinoma and T-cell lymphoma!
what location is most affected by tropical sprue?jejunum and ileum (secondary vit B12 or folate deficiency)
what area absorbs folate?jejunum
what area absorbs vit B12?ileum
whats the classic site of involvment in whipple disease?small bowel lamina propria
only cancer involving the SMALL bowelcarcinoid tumor
small bowel shows submucosal polyp like nodulecarcinoid tumor = presents as polyp like nodules
5-HIAA in urine is indicative of what?carcinoid tumor
what part of the heart is affected by carcinoid heart disease?right sided valvular fibrosis --> tricuspid regurg and pulmonary valve stenosis

Section 6

Question Answer
what causes acute appendicitis in KIDS?obstruction due to lymphoid hyperplasia
which IBD: crypt abscesses with neutrophilsUC
whats the location of UC?rectum to cecum
loss of haustra/lead pipe sign,Ulcerative colitis
UC or crohns: toxic megaCOLON and carcinomaulcerative colitis
associated with primary sclerosing cholangtis and p-ANCA+ulcerative colitis
smoking PROCTECTS against this IBDulcerative colitis
whats the most common site of crohns disease?ileum
lymphoid aggregates with GRANULOMAScrohns disease
cobblestone mucosa, creeping fat, string signcrohns disease
calcium oxalate KIDNEY stonescrohns disease
associated with ankylosing spondylitis, sacrolitis, polyarthritis, uveitiscrohns disease
name 3 conditions associated with p-ANCA+microscopic polyangitis
ulcerative colitis

Section 7

Question Answer
defective relaxation and peristalsis of rectum and distal sigmoid colonhirschsprung disease (need to biopsy NARROWED region. The DILATED region is normal and dilated bc its filled with poop!)
where is the myenteric/Auerbach plexus located?btw inner circular and outer longitudinal muscle layers of muscularis propria --> regular motility
where is meiSSners plexus located?in Submucosa --> regulates blood flow, secretions and absorption
what is colonic diverticula?outpouching of mucosa and submucosa thru muscularis propria
whats the most common location of colonic diverticula?sigmoid colon
whats the most common cause of ischemic colitis?atherosclerosis of SMA --> ischemia of splenic flexure
abd pain that improves with defecationirritable bowel syndrome
whats the tx for IBS?increase fiber content!
serrated/saw-tooth polyphyperplastic polyp = no malignant potential
what type of polyp is premalignant?adenomatous polyp
describe adenoma-carcinoma sequence (normal colonic mucosa-->adenomatous polyp-->carcinomaAPC mutation (increase risk of polyp formation) --> k-RAS mutation (leads to formation of polyp) --> p53 mutation and increase COX (allows progression of carcinoma)
describe polyp that has increased risk for carcinoma>2cm, sessile growth, villous histology
what is Gardners syndrome?FAP with fibromatosis and osteomas
what is Turcots syndrome?FAP with CNS tumors (medulloblastoma and glial tumors)

Section 8

Question Answer
Name the 2 pathways that lead to the development of colorectal carcinoma1) adenoma-carcinoma sequence
2) microsatellite instability
HNPCC is at increased risk for 3 carcinomas?

HNPCC = defective mismatch repair enzymes
colorectal, ovarian and endometrial carcinomas
Older pt with iron deficiency anemia...?right sided colorectal carcinoma
Pathway for development of LEFT-SIDED carcinoma?adenoma-carcinoma
Pathway for development of RIGHT-SIDED carcinomamicrosatellite instability