Final Exam Flashcards
1
Q
What are causes of acute colitis in adult horses?
A
Salmonella Clostridum difficile and perfringens Enterotoxemia Potomac Horse Fever (late spring to early fall) Antimicrobial induced diarrhea
2
Q
What are causes of acute colitis in foals?
A
Salmonella Clostridium difficile and perfringens Gastric ulcers Rota virus Compromised GIT Antimicrobial induced diarrhea Foal heat diarrhea Equine proliferative enterotoxemia (L. intracellularis)
3
Q
What are causes of chronic colitis in adult horses?
A
Cyathostomiasis
Sand impaction
IBD**
4
Q
What are causes of chronic colitis in foals?
A
Villous atrophy (secondary to clostridium) Lactose intolerance
5
Q
What are clinical signs of acute colitis?
A
Explosive watery diarrhea Malodorous feces Colic Dehydration (skin tent, prolonged CRT and jugular refill) Depression (electrolyte imbalances in the neurons) Laminitis Anorexia Pyrexia Tachycardia Dry or toxic mucous membranes
6
Q
In what percent of adult colitis cases is a definitive diagnosis reached?
A
Definitive diagnosis is obtained in only about 30-50% of cases
7
Q
Clinical pathology, biochemistry, and hematology abnormalities with acute colitis (same as for salmonellosis)
A
Leukopenia (left shift, toxic neutrophils, lymphopenia)
Metabolic acidosis (losing bicarb, hyponatremia, hypochloremia, hypokalemia, hypocalcemia)
Increase PCV and lactate
Protein and fibrinogen may be up or down
Azotemia
8
Q
Salmonella colitis
A
ALWAYS has to be ruled out due to zoonotic potential and risk of hospital outbreak
9
Q
Associated patient abnormalities with Salmonella
A
Acute profuse diarrhea Endotoxemia CV shock Vascular leaking Coagulopathy
10
Q
Clinical signs of salmonellosis
A
Febrile
Tachycardic (± tachypnic)
Dehydrated
11
Q
How can we test for Salmonella?
A
Multiple culture or PCR as it is shed intermittently, each sample needs to be minimum 5-10g of feces
12
Q
Treatment and prevention of salmonellosis
A
Aggressive supportive care Antimicrobials Endotoxemia therapeutic protocol High biosecurity Repeat fecal culture and PCR
13
Q
Potomac Horse Fever causative agent
A
Neorickettsia risticii
14
Q
Clinical signs of Potomac Horse Fever
A
Biphasic fever
Laminitis
Colitis
15
Q
Diagnosis of PHF
A
Paired serum titers and IFAT; confirmation with identification of parasite in WBCs in acute phase
16
Q
Treatment of PHF
A
IV oxytetracycline
Supportive therapy
Laminitis prevention (ice bandages)
17
Q
T or F: There is a vaccine for PHF.
A
True
18
Q
Etiology of Equine Proliferative Enteritis
A
Lawsonia intracellularis
19
Q
Clinical signs of Equine Proliferative Enteritis
A
Lethargy Depression Peripheral edema Diarrhea Colic Weight loss
20
Q
Typical age for horses affected by Equine Proliferative Enteropathy
A
Young (6 months old)
21
Q
Diagnosis of EPE
A
Clinical signs
Ultrasound showing thickening of SI wall
Hypoproteinemia
Positive serology or molecular detection in feces
22
Q
Treatment of EPE
A
Antimicrobial (macrolide + oxytetracycline/chloramphenicol) for 2-3 weeks
Correct hydration, electrolyte derangements, and azotemia if present
23
Q
Etiology of pyogranulomatous pneumonia
A
Rhodococcus equi
24
Q
If Rhodoccus equi is causing enterocolitis, where in the GIT is the lesion?
A
Ulcerative enteritis in the Peyer’s patches of the ileum (may extend to cecum and colon)
25
Treatment of Rhodoccus equi
Macrolides
| Supportive therapy
26
Clostridial colitis (antimicrobial associated enterocolitis) histories
Farm outbreak in foals
Horse recently treated with antimicrobials
Mares when foal is being treated for R. equi
Untreated horse with diarrhea
27
Clostridial toxin A does what?
Induces release of substance P (neurotransmitter) at the dorsal root ganglia
This is cytotoxic
28
Clostridial toxin B does what?
Enterotoxigenic activity and is cytotoxic (necrotizing and hemolytic)
29
What might be visible on a radiograph of clostridial colitis?
Gas and fluid distended intestine with intramural gas
30
Diagnosis of clostridial colitis
```
Quantitative culture (normal flora)
PCR
```
31
How can we differentiate C. difficile from other clostridium?
Immediate submission of samples
Sending in large samples
Transportation of sample frozen and in air-tight containers
Cytotoxin assay [differentiates from C. perfringens]
32
Treatment of clostridial colitis
Supportive care
| Metronidazole (or vancomycin if resistant to metronidazole)
33
Which two organisms are more commonly associated with neonatal enterocolitis than with adult acute colitis?
Cryptosporidium spp
| Giardia spp
34
Inflammatory bowel disease is named based on what?
Histopathological findings
35
Clinical presentation of IBD
```
Progressive diarrhea
Weight loss
Good appetite
Intermittent colic
Dermatitis
Peripheral edema (hypoproteinemia)
```
36
Treatment of IBD
Steroids
| Probiotics
37
Blister beetle toxicosis is caused by what?
Cantharidin absorption consumed in beetle infested alfalfa
38
What is the fatality rate of blister beetle toxicosis?
>50%
39
How does cantharidin cause ulceration?
It is an irritant causing cell damage and necrosis on contact
40
What electrolyte derangements associated with cantharidin toxicosis have not been explained?
Hypomagnesemia
| Hypocalcemia (may be loosely associated with hypoalbuminemia)
41
Diagnosis of cantharidin toxicosis via...
Beetle ID
History
Concentration of cantharidin in gastric juice, intestinal content, and urine
42
Treatment of cantharidin toxicosis
```
Supportive care
Electrolyte supplementation
Oral absorbents (mineral oil)
Laminitis prevention
Endotoxemia treatment protocol
```
43
Other things that can cause diarrhea
```
Acorn toxicity
NSAID toxicity
Grain overload
Intestinal LSA
Peritonitis
Heavy metal toxicosis
Sand colic
Enteric pythiosis
Anaphylaxis
Stress (don't we all know it...)
```
44
When treating a colitis patient, after normovolemia has been attained what are two tests that can help us determine adequate fluid delivery?
Serial central venous pressure
| Serial lactate
45
Endoserum (endotoxin neutralizer) is made how?
Horses are vaccinated with a recombinant mutant of S. typhimurium and the antibodies are harvested
46
How does Polymyxin B work?
Polymyxin B binds to the lipid A region of the endotoxin, thus neutralizing it
47
What is the most effective NSAID for preventing endotoxin-induced prostanoid synthesis?
Flunixin meglumine
48
What drug may be beneficial in preventing laminitis?
Pentoxifylline
49
What are functions of the liver
Process nutrients from food
Store glucose, vitamins, and minerals
Maintain immune function
Remove toxins from the blood
50
What percentage of the liver has to be damaged for clinical signs to present?
70-80% of the liver being damaged will result in abnormal function or failure
51
Clinical abnormalities associated with liver damage
```
Icterus
Photosensitization
Hepatoencephalopathy
Coagulopathies
Colic
Pruritus
Ascites
Weight loss
Diarrhea
Rectal prolapse
Fecal color change
Dyspnea (pharyngeal or laryngeal collapse)
```
52
Clinical signs of acute liver dysfunction
```
Depression
Hepatic encephalopathy
Icterus
Colic
Anorexia
```
53
What substance can be used to test the excretory function of the liver?
Bromsulphalein dye
54
Liver enzymes and how to interpret
SDH: elevation may indicate ongoing parenchymal damage
ALP: not liver specific
AST: not liver specific
GGT: elevation my indicate chronic liver disease
55
What coagulation factors are produced in the liver?
I, II, V, VII, IX, X
56
What toxicity and disease have been associated with type III photosensitization in horses?
Pyrrolizidine alkaloid toxicity
| Theiler's disease
57
Treatment of photosensitization
Eliminate photodynamic agent
Provide cover from the sun
Treat as a skin burn (fluids, electrolytes, antibiotics, anti-inflammatories, pain control)
58
Hepatic encephalopathy clinical signs
```
Frequent yawning
Abnormal behavior
Aimless wandering (apparent blindness) and foot stomping
Head pressing
Circling
Seizures
```
59
How might aromatic amino acids cause hepatic encephalopathy?
Increase inhibitory neurotransmitters (GABA and L-glutamate)
Alter catecholamines
Alter MAOs
60
What drug (and class) improves the neurologic state of hepatic encephalopathy?
Flumazenil (benzodiazepine antagonist)
61
Etiologies of Idiopathic Acute Hepatic Disease aka "Serum sickness" aka "Theiler's Disease"
Viral infection with Theiler's disease
Hypersensitivity type III
Dietary factor (pastured horses)
Pyrrolizidine alkaloid toxicosis
62
Clinical signs of IAHD
```
6-8 weeks post-vaccination
CNS signs
Icterus
Yawning (early sign)
Photodermatitis
Intravascular hemolysis w/ or w/o hemoglobinuria
Weight loss
Ventral edema
```
63
What liver enzyme is helpful to monitor in outbreaks of IAHD
GGT (increased before onset of clinical signs)
64
Histopathology of IAHD
Hepatocellular central and mid-zonal necrosis
Accumulation of mononuclear cells and neutrophils in the portal region
Bile ductule proliferation
65
On necropsy, how is the liver of a patient with IAHD often described?
Flaccid liver or "Dishrag liver"
66
Signalment for cholelithiasis
Middle age to older
| No sex or breed predilection
67
Define choledocholithiasis
Stone found in the common bile duct (most common biliary obstruction in equine patients)
68
Composition of choleliths includes...
```
Bilirubin
Bile pigment
Cholesterol esters
Ester of cholic and carboxylic acid
Calcium phosphate
Sodim taurodeoxycholate
```
69
Pathogenic mechanisms proposed for cholelithiasis
```
Ascending biliary infection (cholangitis)
Parasitism (ascarid)
Biliary stasis
Change in bile composition
Foreign body
```
70
Clinical signs of cholelithiasis
Colic with pyrexia and icterus ongoing for 2 weeks
71
Diagnosis of cholelithiasis
Ultrasound (75% diagnosed via this method) of the R 14-16 ICS
Hepatomegaly
Increased hepatic echogenicity
72
What bacteria can be cultured in cases of cholelithiasis?
Bacterioides vulgatus
| E. coli
73
Histopathology with cholelithiasis
Periportal fibrosis
Bile duct hyperplasia
(Suppurative cholangitis)
74
Treating cholelithiasis
```
Medical:
-broad spectrum abx
-fluids
-NSAIDs
-DMSO
-Diet
Surgical:
-choledocholithotomy
-choledocholithotripsy
```
75
With which liver disease can we see moist exfoliative dermatitis and necrotic leathery skin along the coronary band?
Chronic active hepatitis
| Moist exfoliative dermatitis: aseptic vasculitis
76
Treatment of chronic active hepatitis
Supportive care
Corticosteroids (if LPC infiltrate seen on biopsy)
Antimicrobials
Anti-inflammatories
Colchine (inhibit collagen production and reduce inflammation caused by macrophages/cytokines)
77
Etiology of Tyzzer's disease
Clostridium piliformis (gram - anaerobic spore forming intracellular rod shaped)
78
Who is most commonly affected by Tyzzer's disease
Foals (7-14 d old) ESPECIALLY foals born in the spring
| Rapidly fatal
79
Hematology abnormalities with Tyzzer's disease
```
Elevated liver enzymes
Severe hypoglycemia (<20mg/dL)
```
80
Diagnosis of Tyzzer's disease
PCR
| Necropsy (Warthin-starry stain)
81
What medications can decrease blood ammonia?
```
Mineral oil
Oral neomycin
Oral lactulose
Metronidazole
Low protein diet and small meals
```
82
Atopic dermatitis type of reaction and clinical signs
```
Type I (IgE)
Pruritus, alopecia, erythema, urticaria, papules
```
83
Erythema multiforme is death of what type of cells?
Keratinocytes
84
Where does leukocytoclastic vasculitis occur and what is the age of the patient?
Lower extremities (pasterns) lacking pigment, mature horses
85
Pemphigus foleaceus definition
Intra-epidermal acantholysis and intracellular deposition of immunoglobulins
86
With pemphigus foleaceus, what are type of antibodies are involved and what do they target?
Autoantibodies targeting transmembrane proteins (releases proteolytic enzymes which destroy cell attachments causing vesicles and intraepidermal clefts)
87
How is pemphigus treated?
Immunosuppressives
88
Pemphigus vulagaris, what immunoglobulin and what is is directed against?
IgG against epidermal transmembrane proteins (same as pemphigus foliaceous)
89
What is the common name of dermatophytosis?
Ringworm
90
What is the causative agent of ringworm in horses?
Microsporum equine and Trichophyton verrucosum
91
How is ringworm spread and what is the incubation period?
```
Direct contact (or grooming equipment)
Incubation period is 1-6 weeks
```
92
What is the prognosis of dermatophytosis?
It is a self-limiting infection, lasting 1-4 months
93
What is the treatment for dermatophytosis?
Topical ketoconazole shampoo
Anti-inflammatory agents
Systemic griseofulvin
Equipment disinfection
94
What is the common name for dermatophilosis?
Rain rot
95
What is the causative agent of rain rot in horses?
Dermatophilus congolensis, a gram +, branching, filamentous anaerobic bacteria
96
What are the three conditions required for development of rain rot?
1. Carrier animal
2. Moisture
3. Skin abrasion
97
When is dermatophilosis seen most commonly?
Fall and winter months
98
Where are dermatophilosis lesions located on the patient?
Dorsal aspect
99
What is the treatment for dermatophilosis?
Remove from wet environment
Remove all crusts
Wash patient with ionophores or lime sulfur
Prescribe antimicrobials
100
What part of the body is affected by equine staphylococcal cellulitis?
Usually the hind limbs, one limb at a time
101
Clinical signs of equine staphylococcal cellulitis
```
Prominent limb swelling, warm and painful to the touch, ± pitting edema
Lameness
Pyrexia
(Lethargy)
(Anorexia)
```
102
What leads to equine staphylococcal cellulitis?
Injury or trauma (including procedures)
103
Treatment of staphylococcal cellulitis
Eliminate infection (broad spectrum abx)
NSAIDs (pain modulation)
Hydrotherapy
104
T or F: surgical debridement is necessary for the treatment of equine staphylococcal cellulitis
If medical management fails, surgical debridement and drainage is necessary
105
Who is affected by chronic progressive lymphedema most commonly
Draft horses
106
Where on the patient is chronic progressive lymphedema noted?
Distal limb
107
What is the causative agent of Pigeon fever?
Corynebacterium pseudotuberculosis (gram +)
108
Where on the patient are Pigeon fever lesions found?
Pectoral region (rupture in 1-4 weeks)
109
What is the common name for Pythium infection?
Swamp cancer/Florida horse leech/Kunker
| Casused by Pythium insidiosum (protozoa)
110
Cutaneous habronemiasis lesions are found where
Wound sites
111
When there is a cutaneous habronemia lesion at the medial canthus of the eye, what is it called?
Dracocystitis
112
Papillomatosis affects what age group and what is the etiology
Young animals most affected
| BPV 1-10
113
What causes aural plaques
Possibly viral papilloma
114
T or F: aural plaques resolve spontaneously
F
115
How are aural plaques treated?
Imiquimod topical
| Cryosurgery
116
How is SCC treated in the equine patient
Surgical excision
5-FU (5-flurouracil)
Intralesional cisplatin
117
What is the most common tumor in horses?
Equine sarcoids
118
What organism is associated with pathogenesis of equine sarcoids?
Bovine papilloma virus
119
What is equine sarcoids?
Fibroblastic tumor, slow growing, no metastasis; NOT a benign tumor
120
What are the types of equine sarcoids and what do the lesions look like?
Occult (circular alopecia)
Verrucous (sessile or pedunculate)
Nodular (invasive, destroying adjacent tissue)
121
Treatment of equine sarcoids
```
PCR for BPV 5-6 on margin after surgical excision
Topical caustic ointment
5-FU
Intralesional chemo
Radiation
```
122
Equine melanoma is associated with what horses
Gray horses
123
Where are melanoma lesions commonly found
Ventral tail, perineum, external genitalia, lip, udder, periocular
124
Treatment of melanoma
Excise dermal tumors
Cimetidine PO for 16wk
Cisplatin intralesional
125
How is eosinophilic granuloma diagnosed?
Biopsy histopath reveals collagen surrounded by granulomatous inflammation (eosinophils, lymphocytes, histiocytes)
126
Who is affected by hereditary equine regional asthenia
QH and related breeds
127
What is the cause of HERDA
mutation in the pro collagen I N-proteinase (cyclophilin B--PPIB defect)
128
What is a clinical sign of HERDA?
Skin on back/neck easily torn or stretched (seroma, hematoma)
129
Equine B cell LSA has been demonstrated to be caused by what?
Estrogen secreting ovarian tumor
130
What scale is used to body condition score horses?
Henneke (1-9)
