Gastrointestinal Flashcards
Regarding GI bleeding:
–Most common in purebred vs working dog vs mixed breed?
–Most common in stomach vs duodenum vs both?
–Association with liver dz, kidney dz, IBD? (mild/moderate/none)
–Working dogs
–Stomach 88%, duodenum 12%, both 6%
–No association with liver or kidney disease, IBD
JVIM 2021, Pavlova
Regarding a small study of NSAID treated dogs:
–Proportion of dogs with gastric ulcers?
–Proportion that were symptomatic?
–Conclusion to draw regarding NSAID tx?
–10/12 (83%) had gastric ulcers
–None symptomatic
–Be cautious if dog has other factors predisposing to GI ulceration, otherwise do not withhold NSAIDs just because GI ulceration is common
JVIM 2021, Mabry
When does BUN peak and normalize post blood ingestion? Overall, how useful is BUN/creat ratio to detect occult GI bleeding?
BUN peak 4.5-10hrs, back to baseline at 24hrs
Overall BUN/creat ratio is not useful
JVIM 2021, Stiller
Regarding video capsule endoscopy:
–Diagnostic yield for dogs with clinically overt GI bleeding?
–Most common complication and prevalence? At least one thing that helps with this?
–77%
–Incomplete study 46%. Endoscopic deployment into SI can help. No standardized GI prep (fasting time, colon prep, etc) in human or vet med and there is conflicting data regarding prokinetics.
JVIM 2021, Stiller
What is the proportion of calcium in each category? Which are biologically active, and which can be measured?
–Protein bound
–Complexed
–Ionized
–Protein bound 55% – inactive, measurable
–Complexed 10% – active, not measurable
–Ionized 35% – active, measurable
JVIM 2021, De Witte
How do tCa and adjusted Ca (aCa) compare in terms of relative sensitivity and specificity for ionized hypocalcemia (ie, which is a better screening test, and which is a better “confirmatory” test)?
For the latter, if low, does that suggest the iCa is at least (mild, mod, or severely) low?
tCa more sensitive (better screening), aCa more specific
If aCa is low, probably at least moderately (and clinically relevant) low iCa
JVIM 2021, De Witte
Regarding feeding tube placement around the time of PLE diagnosis:
–At least 3 theoretical benefits?
–Frequency of significant complications?
–Impact on MST?
Theoretical benefits
–Improved mucosal function/integrity
–Improved mucosal immune function
–Vit D
–Essential AA
No significant complications with placement in a study of 21 dogs
Improved survival – feeding tube dogs MST 1.5yrs, no tube MST 9mo
JVIM 2021, Economu
In IBD dogs who clinically improve with treatment, do endoscopic appearance of GI and/or GI histo also improve?
Gross appearance improves, GI histo does not
JVIM 2021, Lee
High-mobility group box 1 (HMGB1) is a chromosomal protein that is released from damaged cells. It is a useful marker in human IBD (feces used more than serum) and canine HMGB1 is identical.
–As a noninvasive test for IBD, is it better for screening or confirmation?
–Does it correlate with CIBDAI score and/or histopath?
–Screening test (sens/spec 96/76) – can be affected by pancreatitis
–Correlates with histopath but not CIBDAI
JVIM 2021, Lee
Performance of contrast-enhanced ultrasonography to differentiate IBD vs healthy dogs?
No difference
JVIM 2021, Linta
Regarding TEG findings in chronic inflammatory enteropathy (CIE) dogs with and without hypoalbuminemia:
–Which were hypercoagulable?
–Are they hypo- or hyperfibrinolytic?
–What ref lab coag test positively correlates with max amplitude, and can thus potentially be used as a surrogate if TEG not available?
–CIE dogs with and without hypoalb are hyprecoagulable
–Hyperfibrinolytic
–Fibrinogen
JVIM 2021, Wennogle
The AA homocysteine can be increased in IBD patients with low ____(x)_____. Homocysteine can (incr vs decr) coagulability in human IBD.
Measuring (x) as a surrogate for homocysteine, does this correlate with TEG in IBD dogs? What conclusion can be drawn from this?
High homocysteine if low folate, B12, B6
High homocysteine –> hypercoagulable
B12/folate do not correlate with TEG –> so homocysteine may not be playing a major role in dog IBD hypercoagulability
JVIM 2021, Wennogle
Does low vit D in IBD dogs contribute to coagulation abnormalities?
Yes – hypercoagulable
JVIM 2021, Wennogle
Regarding clinical presentation, which was more common in feline IBD vs LSA, vs no difference?
–Signalment
–Duration of signs
–Polyphagia
–Hematochezia
–LSA: males > females; otherwise no difference (age, breed, body weight)
–LSA longer duration of signs
–Polphagia – LSA
–Hematochezia – IBD
JVIM 2021, Freiche
Regarding bloodwork and AUS, which was more common in feline IBD vs LSA, vs no difference?
–CBC/Chem abnormalities
–Hypocobalaminemia
–Jejunal lymphadenopathy
–Scant peritoneal effusion
–Jejunal mucosal thickening
–Jejunal muscularis thickening
–LSA: hypocobalaminemia, jejunal lymphadenopathy, FF, jejunal mucosal thickening
–No difference CBC/Chem or jejunal muscularis thickening
JVIM 2021, Freiche
Which is the minimum deepest intestinal layer affected in feline low grade intestinal lymphoma (LGITL)?
Are epitheliotropism and intraepithelial lymphocytes/nests/plaques more common in IBD or LGITL?
Are IBD and LGITL primarily T cell, B cell, or mixed?
Lamina propria
LGITL
LGITL – T cell; IBD – mixed
JVIM 2021, Freiche
In a study of surgically biopsied IBD vs LGITL cats:
–Which had more significant fibrosis?
–Gradient of LGITL? (apical to basal vs basal to apical)
–Frequency of submucosal lesions in IBD?
–Did IBD or LGITL have more homogenous lesion distribution?
–LGITL
–Apical to basal
–9%
–IBD
JVIM 2021, Freiche
In a study of surgically biopsied IBD vs LGITL cats:
–What is Ki67 a marker of? Is it higher in IBD or LGITL?
–Is PARR reliable for differentiation?
–Marker of proliferation – higher in LGITL
–No
JVIM 2021, Freiche
Regarding abx use for acute hemorrhagic diarrhea syndrome (AHDS):
–When should these be considered? How is this criteria somewhat misleading?
–One study showed which single abx may be sufficient?
–Overall survival rate? How did abx impact this?
–Consider if suspicion for sepsis – but many criteria are nonspecific and could be due to hypovolemia (incr HR, RR, hypotension)
–Ampi
–96% survival, no difference in abx vs non-abx group
JVIM 2021, Dupont
How do previous GI insult (parvo, AHDS, etc) or abx use early in life, respectively, potentially predispose to chronic enteropathy later in life?
–Previous GI insult: GI barrier breakdown –> exposure to food and flora Ag –> decr tolerance
–Early abx: decr flora diversity –> decr immunoregulation
JVIM 2021, Skotnitzki
What is the proportion of dogs that will have chronic/recurrent GI signs later in life after an episode of acute hemorrhagic diarrhea? What proportion will resolve with an elimination diet?
28% chronic GI signs
81% diet responsive
JVIM 2021, Skotnitzki
Regarding subtotal colectomy in cats:
–Risk of dehiscence?
–How long post op does it take for stool quality to improve? Proportion of cats with long term liquid stool?
–Frequency of constipation recurrence and time frame? Usually refractory or amenable to medical management?
–Frequency of death/euth due to megacolon despite sx? At least three factors that impacted survival?
–2% risk of dehiscence
–2mo for ileum to adapt for incr water absorption. 17% of cats have long term liquid stool.
–32% constipation recurrence at median ~1yr. Most amenable to medical management.
–14% death/euth due to megacolon. Shorter survival with preop heart disease, postop tenesmus, thin BCS, long term liquid feces, or major postop complications (resulting in death or re-cut)
JVIM 2021, Grossman
What is the impact of ICJ resection (vs retention) on the following aspects in constipated cats treated with subtotal colectomy:
–Recurrence of constipation
–Long term liquid feces
–QoL
–Survival time
–No impact on recurrence of constipation (ie, ICJ resection did not prevent)
–Incr risk of long term liquid feces
–Worse QoL
–Shorter survival
JVIM 2021, Grossman
Is primary or secondary hyperlipidemia more common?
What are at least two drugs and four disease states that can cause secondary hyperlipidemia?
Primary is more common
Secondary:
–Drugs (steroids, phenobarb)
–Endocrine
–Cholestasis
–PLN
–Pancreatitis
–Obesity
JVIM 2021, Munro
Is hyperlipidemia usually clinical or subclinical? What are at least four possible complications?
Usually subclinical
Complications:
–Pancreatitis
–GB mucocele
–Vacuolar hepatopathy
–Insulin resistance
–Proteinuria
–Seizures
JVIM 2021, Munro
What are at least 3 MoAs of fibrates for treatment of hyperlipidemia?
What is the minimum goal TG for successful tx?
MoAs:
–Incr lipoprotein lipase
–Incr liver FA uptake
–Decr liver GT produciton
–Incr removal of low-density lipoprotein cholesterol (LDL-C)
–Incr production of HDL-C
Goal = TG <500
JVIM 2021, Munro
Fibrates have some drawbacks.
–Adverse effects are common in people – which organ system is usually affected? What organ is less commonly affected but potentially more serious?
–What are two problems with bioavailability?
–GI side effects are common
–Idiosynchratic hepatotoxicity – variable LE patterns, asymptomatic to chronic liver disease
–Bioavailability – lipophilic (give with food), unpredictable absorption depending on formulation (TriCor fenofibrate is fairly predictable)
JVIM 2021, Munro
Regarding a small study of hyperlipidemic dogs treated with fenofibrate (TriCor):
Efficacy:
–Proportion of dogs with normalized TG?
–Impact of starting TG on outcome?
Safety:
–Relative frequency and severity of clinical and biochemical adverse effects?
Efficacy: all dogs had normalized TG independent of starting TG (incl some not fed a low fat diet)
Safety: 1 dog had quiet demeanor and firm stools; no biochem issues
JVIM 2021, Munro
A recent study in PLE dogs looked for predictors of who would and wouldn’t respond to low fat diet.
–Which dogs is it worth trying for?
–What finding on workup was most common in nonresponders?
–Was alb different in responders vs nonresponders?
–Does food responsiveness affect prognosis?
–Full responders tended to be younger and have lower CCECAI scores but it couldn’t differentiate full vs partial responders, AND overall only a few dogs didn’t respond to diet at all. Bx (ex: presence of lymphangiectasia) didn’t predict response. Ultimately, reasonable to try diet in everyone.
–Mesenteric lymphadenopathy – 60% nonresponders, 13% responders
–No difference in albumin
–Food responsive PLE had longer survival
JVIM 2020, Nagata
Regarding gastric wall edema in hypoalbuminemic dogs:
–Prevalence?
–Compare its appearance with what is seen with acute pancreatitis
–Correlation with albumin?
–21%
–Hypoalb –> more diffuse edema, add’l layering within the submucosa (prob separation of collagen fibers). Panc –> focal/peripancreatic, no extra layers. Both –> intact wall layering.
–Prevalence did not correlate with severity of alb; and can resolve despite no change in alb
JVIM 2020, Murakami
True or False:
–Fecal culture should be included in the routine workup for chronic diarrhea in dogs to rule out enteropathogenic bacteria (such as salmonella, camp, C. perf, C. diff, pathogenic E. coli).
–C. perf can be found in 94% of healthy dogs via PCR and 80% via culture.
–Fecal culture and PCR perform similarly in assessment of the microbiome.
–False. A study of 18 dogs found zero positives (except E. coli of questionable significance) – doesn’t seem to be a major cause.
–True – presence of the bacteria is not a problem, rather certain associated enterotoxins
–False – cultures perform horribly, massively underestimate anaerobes, etc
JVIM 2020, Werner
What three breeds are overrepresented in E. coli granulomatous colitis? What defect in their defenses predisposes them?
–Boxers, Frenchies, Mastiffs
–Defect in macrophage sensing/killing intracellular (intramacrophage) E. coli
JVIM 2020, Manchester
Abx penetration into what cell type is essential for clearance of E. coli granulomatous colitis?
Macrophages
JVIM 2020, Manchester
What was the prevalence of fluoroquinolone resistant E. coli in a recent study about E. coli granulomatous colitis?
What was the long term prognosis for dogs treated with culture-directed abx? Did age play a role?
–62%
–Good; also, all dogs that made it to 4yrs old did well long term
JVIM 2020, Manchester
True or False regarding E. coli granulomatous colitis:
–If a dog does not respond to abx in the first 4 weeks, it is considered a treatment failure and a different abx is indicated.
–Resistant abx MIC in vitro does not necessarily mean it won’t work in vivo.
–Not necessarily – 60% may go on to have partial or complete response
–True – some abx combos can act synergistically, and in vitro may underestimate in vivo susceptibility
JVIM 2020, Manchester
Nuclear scintigraphy is a highly sensitive method to detect reflux and microaspiration.
–What proportion of 12 healthy mesocephalic dogs had reflux? Microaspiration?
–For those with reflux, what part of the esophagus did it typically reach? How does this compare with what is typically seen in fluoro studies? How often were these large volume?
–100% had reflux, none had microaspiration (but r/o type II error)
–Middle esophagus, occ large volume. Fluoro studies found usually no higher than distal esophagus (r/o incr sensitivity of scintigraphy).
JVIM 2020, Grobman
Ileocecocolonic perforations secondary to endoscopy are a rare but significant possible complication.
–What two physical processes at the time of scope can cause this?
–Do species, disease process, and/or operator affect risk? How does this compare with risk of gastroduodenal perf?
–3 clues at the time of scope that an ICC perf has occurred?
Mechanical trauma (most common; scope, forceps), barotrauma (excessive insufflation)
Risk:
–Dogs overrepresented in the study BUT cats at higher risk for gastroduodenal endoscopic perfs. R/o bias (less likely to do lower scope in cats).
–No significant underlying disease (worst = mod IBD) at the site of perfs in this study. Gastroduodenal perfs are more likely with severe IBD, ulceration, or LSA.
–Two thirds of cases were with residents/interns – r/o incr risk with inexperienced operator vs reporting bias
Directly see tear, unable to hold insufflation, abdominal distension refractory to suction
JVIM 2020, Woolhead
Ileocecocolonic perforations secondary to endoscopy are a rare but significant possible complication.
–Post scope, what would put ICC perf on your ddx list? (Generally speaking)
–Diagnostic test of choice?
–Treatment of choice? How likely is recovery if dx is delayed up to 5 days post scope?
–Consider ICC perf if patient does not recover as expected. Vague CS (leth, inapp, abd pain, retching).
–AXR – see free gas
–Surgery. Most did well with perf repair, some had ICJ resection. Most animals with delayed diagnosis still did well.
JVIM 2020, Woolhead
When incorporating IHC and PPAR, what proportion of definitely IBD cats (based on histopath alone) were reclassified to LSA?
Almost half
JVIM 2020, Chow
–Rank intestinal segments according to how commonly they are affected by LSA in cats. How does this affect the recommendation for endo vs sx bx?
–When using histopath, IHC, and PARR to classify IBD vs LSA, how often is LSA only found in the ileal bx? (frequently, sometimes, rarely)
–Jejunum > duodenum > ileum. Endoscope can reach the jejunum in most cats though.
–Rarely – upper GI bx are usually adequate
JVIM 2020, Chow
Regarding iron deficiency:
–What is the difference between functional and absolute iron deficiency?
–What changes to iron parameters (%TSAT, ferritin) are expected with each? Which parameter can also be affected by inflammation, making interpretation difficult?
–Can FID and AID exist concurrently?
Functional iron deficiency (FID):
–Normal or incr iron stores but unavailable for heme synth
–Inflammation –> hepcidin –> decr ferroportin on GI cells –> decr iron absorption
–Expect decr %TSAT with normal to incr serum ferritin
Absolute iron deficiency (AID):
–Chronic blood loss esp GI (most common), decr intake, malabsorption
–Expect decr %TSAT with decr serum ferritin
Difficult to truly dx FID vs AID because they can coexist, and ferritin is an acute phase protein.
JVIM 2020, Hunt
In cats with chronic enteropathy, which RBC parameter correlated with iron deficiency?
Retic Hb; not MCV, some iron deficient cats were not anemic
JVIM 2020, Hunt
Why is methylmalonic acid a more sensitive marker of hypocobalaminemia?
In normalcy: Methylmalonyl-CoA –[methylmalonyl-CoA mutase + cobalamin]–> succinyl-CoA
No B12 –> MMA builds up. So, high MMA = low B12 at a cellular level.
JVIM 2020, Kook
What clinical sign is associated with hypocobalaminemia in cats with chronic enteropathy?
Polyphagia + weight loss
JVIM 2020, Kook
