git Flashcards
what are the causes of toxic megacolon
pseudomembranous clotiis and ulcerative colitis
Nonsevere: leukocytosis < 15,000/mm3 and serum creatinine < 1.5 of baseline
Severe: leukocytosis ≥ 15,000/mm3 OR serum creatinine ≥ 1.5 of baseline
Fulminant: decreased blood pressure, shock, ileus or toxic megacolon
when do we place a tips
we place a tis if the patient has reccurent variceal hemorrhage it impairs ammonia clearnece
how does zollinger ellison syndrom e present
ulcers in the gastrium and dudodenum plus inactivation pf pancreatic enzyme = decreased absorption of fats
how does drug induced esophagitis look like
The characteristic finding on upper endoscopy is a punched-out ulcer with normal surrounding mucosa, often located at a site of anatomic narrowing
explain pathogensis of hepaticellular accumulation of lipids in obesity
In obese individuals, adipokines released from fat depots decrease the insulin sensitivity of peripheral tissue. Increased peripheral insulin resistance causes post-prandial hyperglycemia, which, in turn, increases insulin secretion. This hyperinsulinemia triggers lipid uptake as well as lipogenesis within hepatocytes (non-alcoholic steatosis). The precursors of triglycerides (e.g., fatty acids, glycerols) and the byproducts of lipid metabolism can cause hepatocellular damage (non-alcoholic steatohepatitis, NASH) by inducing oxidative stress
what causes sma syndrome
Rapid weight loss, severe burns or other inducers of catabolism, prolonged bed rest • Also caused by pronounced lordosis or after surgical correction of scoliosis • SMA gets trapped between transverse portion (3) of duodenum and aorta • Postpranidal pain, especially in LUQ
retroperitoneal hematoma
Retroperitoneal hematoma is a common complication of abdo and pelvic trauma. The pancreas is a retroperitoneal organ, and pancreatic injury is freq a source of retroperitoneal bleeding.
pathopys of portal hypertension
Vasoactive agents cause venous dilation of the splanchnic arterial vasculature further intrahepatic vasoconstriction > increased portal vein hydrostatic pressure leading to ascites • Kidney sense decreased perfusion and activate RAAS
where is IMV located
IMV does not course with IMA
• IMV drains to splenic veins to portal
vein
what supplies the ant iliac crest
Deep circumflex iliac art: from external
iliac > supplies ant iliac crest
how does splenic laceration present with
Rigid abdomen and left shoulder pain
Kehr sign
what causes phrenc neerve irritation
(ruptured spleen,
peritonitis, hemoperitoneum, diaphragm
myocardial contusion
Mid anterior chest wall pain
• SOB
• Persistent tachycardia
• New ECG findings
drainage of hemarrhoids
hemorrhoids results from abn distension of a portion of the anal AV plexus. The vascular components of internal hemorrhoids drain into the sup. rectal vein, which subseq drains into the IMV. Band ligation of hemorrhoids cuts off their blood supply, causing them to degen
what is dynergic defecation
Dyssynergic defecation occurs when the puborectalis muscle or the int.or ext. anal sphincter fails to relax during defecation, leading to chronic constipation. Dyssynergic defecation is usually considered a fxnal disorder and occurs more commonly in the elderly but may also occur w/ certain neuro disorders (e.g. PD, MS) or trauma.
why we have constipation in cauda equina
The pelvic splanchnic nerves (S2- S4) provide parasympathetic innervation to the bowel and bladder, and their impairment in CES can cause constipation and difficulty urinating. Other SSx of CES incl radicular LBP and leg weakness (sciatic nerve) as well as saddle anaesthesia (pudendal, ilioinguinal nerves). Gastrointestinal & Nutrition (GI) Anatomy (Anat) 3 1525
where does the visceral fibres for appendicitis enter
afferent pain fibres entering at the
T10 lvl in the spinal cord.
how to identify appendiz
The teniae coli are 3 separate smooth muscle ribbons that travel longitudinally on the outside of the colon and converge at the root of the vermiform appendix
what are the two anatsomoses present in the intestine
the marginal artery of Drummond, which is the principal anastomosis, and the inconsistently present arc of Riolan (mesenteric meandering artery).
manifestations of chronic gerd
impaired peristalsis, inflammation,
stricture or malignancy
portovaval anastomoses
L gastric vein > esophageal vein
• Sup rectal vein > mid and inf rectal vein
• Paraumbilical vein > sup and inf
epigastric vein
explain development of brown pigment stones
Brown pigment gallstones are composed of Ca salts of unconjugated bilirubin and arise 2° to bacterial or helminthic infection of the biliary tract. β- glucuronidase released by injured hepatocytes and bacteria hydrolyzes bilirubin glucuronides to unconjugated bilirubin. The liver fluke Clonorchis sinensis has a high prevalence in East Asian countries and is a common cause of pigment stones.
explain mechanism of RAS
Ras GTP activated MAPK
> enters nucleus and influe
explain lactase deficiency how it works
Damaged cells and sloughed off and
replaced with immature cells with low
lactase concentration
what enzyme deficeintin homocystinuria
cystathionine synthase
base excision repair chemicals
Cytosine deamination to uracil
Excessive nitrite consumption promotes
cytosine to uracil, adenine to hypoxanthine,
and guanine to xanthine
explain the vitelline duct abnormalities
Persistent vitelline duct: meconium from
umbilicus
• Meckel: partial closure (patent portion
attached to ileum) > fibrous band may
connect to umbilicus
• Vitelline sinus: partial closure (patent
portion attached to umbilicus)
• Vitelline duct cyst (enterocyst): central
portion remains patent
umbilical hernia
Failure of umbilical ring to close
umbilical hernia
Failure of umbilical ring to close defect in the linea alba and Px as protrusions at the umbilicus that are soft, reducible, and benign. Associated with Downs, hypothyroid, Beckwith Wiedemann
hirschprung disease
Make auerbach and meissner plexus • Move from cranial to caudal • Proximal colon by week 8 • Rectum by week 12 • Failure to migrate = Hirschsprung (rectum and anus always involved, sigmoid involved 75% of the time)
function of b cells in peyer patches
B cells migate to lamina propria in
Peyer’s patches > synthesize IgA dimers
Hepatic abscess
S. aureus can cause hepatic abscesses via heme seeding of the liver. Enteric bacteria (e.g. E. coli, Klebsiella, and enterococci) can cause hepatic abscesses by asc the biliary tract (i.e. asc cholangitis), portal vein pyemia, or direct invasion from an adjacent area
what causes cholangitis
E coli or Klebsiella
or enterococci
Isospora belli
diarrhea in hiv
hep c genome variation
Hypervariable genome coding for 2
envelope glycoprotein
which is the only polymerase with 5-3 activity
explain the hiv env protein
DNA Poly 1 • Only poly to have 5' >3' exonuclease activity s env GP seqs also contain an HVR prone to freq genetic mut.
MOA of shigella toxin
Inhibits protein synthesis by removing
adenine of 60S > preventing tRNA binding
salmoella action
Penetrates GI tract > travels to mesenteric
lymph nodes > picked up by macrophages
and survives
why ecoli EHEC
Do not ferment sorbitol (does not
produce glucuronidase)
MOA of yerseina entroclitica
Enterotoxin: increases cGMP causing
diarrhea
clostridium difficile MOA
Both inactive Rho regulatory proteins
involved with actin cytoskeletal structure
maintenance
camp jeujeni moa presentation
dogs). MFx usually
include fever, cramping
abdominal pain, and watery
diarrhea that may be bloody.
tell histopath of pseudomembranous colitis and most severe complication
associated with white, patchy pseudomembranes on the bowel mucosa. These pseudomembranes consist of a neutrophilpredominant inflammatory infiltrate, fibrin, bacteria, and necrotic epithelium. Patients may develop a nonobstructive colonic dilation known as toxic megacolon, which can lead to colonic perforation.
what bacteria can affect perforation of small bowel
candida
which bacteria causes intraabdominal abscess
B Fragilis is most common anaerobic gram neg involved • Forms abscess (special polysaccharide forms abscess) • E coli > enterococci > and strep are also common
lethal complication of strongyloides stercalis
This can result in a
hyperinfec syndrome char by
massive dissem of the organism,
leading to MOD and septic shock
when do you have increased chances of hyperinfection
Hyperinfection also with
immunosuppression and HTLv 1 due to
lack of Th2 > no IgE and IgA
hepatic adenoma
regresses with ocp right lobe • Associated with contraceptive and anabolic steroids • Prone to rupture
what base translocation alphatoxin causes
aflatoxin
exposure is a/w a G:C → T:A
explainn metastasis of ct
Multiple hypodense masses on CT
• Often outgrow vasculature > central
necrosis
