Explain GI Pathology Terms Flashcards

*Due to the conversion of hemoglobin to hematin by acid in the stomach. Therefore, melena indicates that the gastrointestinal bleed is in the upper gastrointestinal tract proximal to where the duodenum attaches to the jejunum.

*INTERNAL hemorrhoids usually involve SUPERIOR hemorrhoidal veins(Above dentate line) and is Mostly painless, but they might tell u that it is painful and ask u why-the answer is THROMBOSIS.*Patient would have prolapse in anus(That usually goes back when they stop shitting, but can get stuck) and would complain of soiling of underwear by mucoid discharge,reddish discharge on toilet paper.

*DUCTAL Epithelium(Endocrine pancreas)-most likely due to exposure to potent secretions for long-time.they REALLY REALLY want you to know that majority of pancreatic cancer arise from DUCTAL EPITHELIUM, do NOT ignore this...

Acute Meckel’s diverticulitis-can mimic Appendicitis, and remember that this is true diverticulum(it contains all layers from mucosa to serosa)and is result of failure of viteline (omphalomesenteric)duct to obliterate- this duct in fetus connects yolk sac to developing gut and can also be called yolk STALK.

*Increased Serum Lipase is most specific for ACUTE pancreatitis(Alcoholic,with epigastric pain that radiates to back) and yes pleural effusion is possibility(Exudate-Rich in cells and protein,LDH/Serum LDH>0.6)...Severe acute pancreatitis can lead to hyperglycemia due to destruction of β-islet cells in the pancreas(Lack of insulin to take glucose from blood into cells,so more remains in blood)*HYPOcalcemia is possibility because of enzymatic fat necrosis>release of negatively charged Fatty acids which will combine with positively charged Calcium and so less calcium is left free in blood.

*Because that means that we have conjucated Hyperbillirubinemia, and even though billirubin enters liver and is conjugated(So it can be excreted in urine and thus urine bilirubin is increased), billirubin can't leave liver and thus can't be deconcujagated by GUT flora into urobillinogen, some of this urobillinogen would be normally reabsorbed and excreted urine, so when billirubin can't reach the gut flora this process can't carry out properly>DECRESED urobillinogen in the urine...*Urine billirubin is increased because billirubin is conjucated in the liver and as there is obstruction, it increases in the blood>More delivered to kidney>More excreted in urine, because conjugated form is water soluble...

*Appendix is most common site of origin for carcinoid tumors HOWEVER Most likely site of origin in patient with Carcinoid SYNDROME(Right sided heart lesions+Flushing+Increased 5HIAA in urine), would be TERMINAL ILEUM, because most commonly metastases takes place from this side(most commonly to liver where it directly releases serotonin into the tribuitaries of hepatic vein>Thus directly enters the systemic circulation, localizations below the liver can't produce the carcinoid SYNDROME because Serotonin will be inactivated in the liver, so the mass should be in the liver itself or above, like in MAINSTEM BRONCHI(Think of Well defined lesion in mainstem bronchi that doesn't damage mucosa, Patient would present with cough,Flushing, diarrhea)

*INAPPROPRIATE ACTIVATION of Pancreatic enzymes, due to Pancreatic duct/ampullarobstruction,Chronic Alcohol,Acinar cell damage,infections....Think of pancreatitis when Serum LIPASE(most specific) is elevated and patient complains of EPIGASTRIC pain that radiates to the back..

*Think in a patient who has CHRONIC epigastric pain,Vomitting,edema,Anorexia....NOW you got to know this if you want really high score:Mentetrier's disease is PROTEIN-Loosing HYPERTROPHIC Gastropathy that involves overactive/increased numbers of EPIDERMAL Growth Factor RECEPTOR(EGFR)..

*Histology reveals WARTHIN TUMOR(PAPILLARY CYSTADENOMA LYMPHOMATOSUM), it is MOST commonly unilateral, however bilateral involvement of salivary glands are possible...These tumors are usually BENIGN, however in few cases it can be malignant...they love to test the fact that this tumor is more common in SMOKERS(Cigarette smoke is predisposing factor)

*Description best fits MUCOEPIDERMOID carcinoma which is MOST COMMON MALIGNANT tumor of salivary gland..

*Description best fits PLEmorpic adenoma which is MOST Common salivary gland tumor and is BENIGN..They love to test the fact that it has potential to recur after surgery...

*Pleomorphic adenoma vs Mucoepidermoid Carcinoma...

*Mass was likely located in PAROTID region, as PAROTID gland is MOST common site of Salivary gland tumors...They WANT you to know that Facial nerve(CN7) can be affected but they also want you to know that this Nerve does NOT innervate parotid gland it just passes trough it on its way....Salivary glands are most commonly BENIGN, HOWEVER involvement of facial nerve is suggestive of malignant transformation(because benign tumor usually doesn't invade nearby tissue, so think of malignant process when there is INVOLVEMENT of facial nerve)..

*Indirectly By causing ACHALASIA, remember that T.cruzi infection could lead to loss of AUERBACH(MYENTERIC)Plexus, loss of Neurotransmitters like NO and VIP(Due to loss of POSTganglionic inhibitory neurons), so as a result we get FAILURE of RELAXATION of LOWER esophageal Spincter....