Infection Flashcards
(116 cards)
True or False:
Cats can be seroposotive for leptospirosis but do not shed organism in their urine.
False – can be urine PCR+, consistent with urine shedding
JFMS 2021, Bourassi
Over half of dogs treated with leptospirosis will have a negative urine PCR by what time frame?
1-2 weeks
JVIM 2021, Hetrick
In one study from 2021, which two abx were most successful for treating lepto?
A) Aminopenicillins
B) Doxycycline
C) Fluoroquinolone
D) Clarithromycin
E) Chloramphenicol
Doxy, clarithromycin
JVIM 2021, Hetrick
In one study from 2021, which two abx were least successful for treating lepto? What is an interesting point about each?
A) Aminopenicillins
B) Doxycycline
C) Fluoroquinolone
D) Clarithromycin
E) Chloramphenicol
Aminopenicillins – would not expect success at all, since thought of as clearing lepto from blood but not renal tubules
Fluoroquinolones – another study found better success, r/o different serovars
JVIM 2021, Hetrick
–Which endothelial marker(s) (sICAM-1, VEGF, Ang-2) can discriminate lepto dogs with and without pulmonary hemorrhagic syndrome?
–Which can differentiate lepto vs other causes of AKI?
–sICAM-1
–None – similar elevation in lepto and AKI
JVIM 2021, Sondregger
Regarding bartonella:
–Gram positive or negative?
–Three most common species in N. America?
–Which are considered pathogenic?
–In general, what types of diseases are associated with it?
–Gram neg
–B. vinsonii subsp berkhoffii, B. henselae, B. koehlerae
–All are pathogenic
–Endocarditis, vascular and lymphatics issues, granulomatous disease
JVIM 2021, Lashnits
Where in the US is bartonella most common?
South (Texas to N Carolina)
JVIM 2021, Lashnits
Which is the most accurate test for septic peritonitis?
–Paired peripheral/effusion glucose
–Paired peripheral/effusion lactate
–Cytology (read by pathologist)
–RIA for bacteria
Cytology
RIA sens 87%, spec 76% – not good enough to rely on by itself
JVIM 2021, Human
A 2yr MN DSH is presented for pelvic limb lameness. Physical exam also reveals retained deciduous teeth and multiple digits are swollen and inflamed around the nails. What is your primary differential? What is the most effective treatment for the nailbeds?
Patellar fracture and dental anomaly syndrome (PADS)
Paronychia – most need amputation
JFMS 2021, Pilot
Regarding schistosomiasis:
–Causative agent? (species, type of organism)
–Life cycle?
Heterobilharzia americana – trematode
Racoon –> eggs in feces –> fresh water –> snails –> cercariae penetrate intact skin of new host –> lungs –> liver –> mesenteric veins –> adults mate –> eggs make proteolytic enzymes to get to intestines (pyogranulomatous inflamm) –> feces
JVIM 2021, Cridge
Regarding schistosomiasis:
–Common signalment?
–Common presentation?
–How do you find asymptomatic dogs?
–Young to middle aged large breed dogs (likely reflects exposure to water, outdoorsy activities)
–Nonspecific GI signs, PU/PD; hepatopathy
–Asymptomatic dogs are usually in the same community as symptomatic dogs (exposed to same water source)
JVIM 2021, Cridge
JVIM 2021, Graham
Regarding workup of schistosomiasis:
–Most common CBC/Chem findings?
–AXR?
–AUS?
–CBC: anemia, eosinophilia (40%)
–Chem: high glob (40%), Ca, LEs, azotemia; low alb (25%)
–AXR: mineralized GI walls, hepatosplenomegaly
–AUS: heterogenous SI wall layering; pinpoint hyperechoic foci in SI, liver, LNs
JVIM 2021, Cridge
What are the two main tests used to diagnose schistosomiasis, and how do they compare to each other?
Fecal saline sedimentation and fecal PCR. The latter is more sensitive (so probably better for tx monitoring) and equally specific.
JVIM 2021, Cridge
What is the treatment for symptomatic schistosomiasis? Cure rate? Outcome if not initially cured?
One small study treated asymptomatic dogs. How did tx differ and how many were durably cured?
Symptomatic: High dose praziquantel x1-3d + fenbendazole x4-14d. Tx failure ~50% (but not all dogs were re-tested – possible bias to refractory cases), all re-treated and cured. May be due to parasite life cycle, reinfection, etc.
Asymptomatic: lower dose prazi (b/c expensive) + fenbendazole
67% durably cured
JVIM 2021, Cridge
JVIM 2021, Graham
Which time interval(s) should follow up testing be done to ensure clearance of schistosomiasis?
What is the survival rate at 6mo?
1 and 2mo
At least 75% survived to 6mo (long term outcome only available for ~1/2 of dogs in the study)
JVIM 2021, Graham
True or False:
Immunocompetent cats rarely develop clinical toxoplasmosis.
True
JVIM 2021, McKenna
True or False:
A positive toxo IgM titer means the cat was infected within the previous 2 weeks.
False – can take 4-10 weeks. Also, may never develop IgM (20% of cases).
JVIM 2021, McKenna
True or False:
Persistently high toxo IgG titers are suggestive of treatment failure.
False – can remain high despite adequate treatment
JVIM 2021, McKenna
Regarding Cytauxzoon felis:
–What type of organism is this?
–How is it transmitted?
–Natural reservoir?
–Typical duration of disease in domestic cats?
–What is the only point of care test and the best sample type(s) for it?
–Protozoan
–Amblyomma americanum (lone star tick)
–Bobcats
–Rapidly fatal
–FNA –> schizont-laden macrophages. Looks kind of like the macrophage ate a clump of platelets. Most frequently found in spleen > PLN > blood smear.
JVIM 2021, Sleznikow
Regarding Chagas disease:
–Causative agent species and type of organism?
–Where is it endemic in the US?
–Transmission?
–Target organ?
–Most common clinical sign?
–Do dogs usually die in the acute or chronic phase?
–Trypanosoma cruzi (protozoan)
–Southern US (Texas and east)
–Kissing bugs or vertical
–Heart –> myocarditis
–Usually presented for arrhythmia
–Chronic
JVIM 2021, Matthews
Regarding Chagas disease (T. cruzi) heart workup:
–What proportion have an abnormal ECG? What two types of arrhythmia are most common?
–What proportion have heart chamber enlargement? Which is most common? Is this associated with outcome?
–Is cTnI usually normal or high?
–95% have abnormal ECG, usually ventricular arrhythmia or AV block
–63% have at least one enlarged chamber. RV most common and associated with higher risk of death.
–cTnI usually high
JVIM 2021, Matthews
How is Chagas disease (T. cruzi) diagnosed?
Usually IFA (degree of titer not proven to correlated with clinical disease)
PCR is not great since primarily an intracellular parasite
JVIM 2021, Matthews
Regarding Leishmania:
–Causative agent and type of organism?
–Transmission?
–Where (worldwide) is it endemic?
–Where is it most common in the US?
–Why are foxhounds overrepresented in the US?
–If a non-foxhound dog is diagnosed in the US, how did they usually get it?
–How is it usually diagnosed? What other organism can cross react with this test?
–Leishmania infantum, protozoa
–Sandflies
–Central and S. America, Europe (esp Spain)
–US: West coast (esp CA), eastern US
–Foxhounds –> vertical transmission
–Non-foxhounds –> most (but not all) have traveled to endemic area (imported rescues, military dogs)
–Titer (T. cruzi can cross-react)
JVIM 2021, Gin
True or False:
Disseminated invasive aspergillosis usually only occurs in immunocompromised cats.
How is it likely transmitted?
True
Inhalation –> lungs –> hematogenous spread (angiotrophic), also hitches a ride in monocytes –> LNs
JVIM 2021, Cormack