Acute colitis Flashcards
Acute colitis
Inflamm of the large colon
Acute Dx
In adult horses is always coming for the large colon and never the small intestine
Fluid balance in the large intestine
NB in fluid and electrolyte balance
60% of water entering large colon and caecum is absorbed back
Daily vol of secreted and reabsorbed water equals total ECV
What are the direct causes of Dx
Increased water and electrolyte content of the faeces
Hypersecretion with malabsorption
What are the indirect causes of Dx
Acute inflamm of colon- incr PG– hypersecretion
Enterotoxins binding to secretory receptors
Malabs of VFA’s and sodium- incr permeability
Abnormal microflora- produce metabolites
Altered intestinal motility
If shorter transit time- no time for water to be reabsorbed
What happens shortly after Dx
Loss of Na, K, Cl and HCO3
Plasma loss to the intestinal lumen (protein loss)- severe
Dehydration
Metab acidosis
Shock
Renal insufficiency
Acute colitis: Bact
Salmonella
Clost: perfringens, difficile
Neorickettsiosis- potomac valley fever
Acute colitis: Parasitic
Strongylosis
Cyathostominosis
Anoplocephalosis= tapeworn disease
Acute colitis: toxic
AB associated Dx
Right dorsal colitis
Cantharidin- produced by blister beatles
Acute colitis: Misc
Intestinal anaphlyaxia
Carb overload
Sand enteropathy
Clinical forms of Salmonellosis
- Carriers: latent or active
- Lethargy, anorexia, fever, neutropenia without diarrhea or colic
- Peracute or acute colitis or enterocolitis (animals might die in the early stages
- Septicaemia with or without Dx (neonatal foals)
Aetiology of Salmonellosis
E enterica var typhimurium var agona
Inf from hospital- stress/other chronic diseases can bring it on
Is zoonotic
Enterotoxin- PG synth- incr secretion– Dx
Salmonellosis pathogenesis
Inflamm- salm enters enterocytes
Enterotoxin enhances the Dx but is not required! Increases the secretion of Cl and water through cAMP
Fibrinonecrotic typhlocolitis
Interstitial edema
Intramural thrombosis or infarcts
Ulceration of LI
Clinical signs of salmonellosis
Depression
Anorexia
Fever, tachycard and tachypnoea
Profuse, watery, smelly Dx
Severe dehydration
Dry, dark or dirty red or purple mm
Prolonged CRT
Tinkling gut sounds at the beginning
Rectal palpation: gas acc in caecum and large colon, edema of wall of LI
Sometimes reflux
Acute laminitis
Clinical pathology of Salmonellosis
PCV>60%
Decreased TPP
Leuco, neutro and thrombocytopenia
Hypo: natraemia, kalaemia and chloraemia
Metab acidosis: HCO3<15mmol/l
Prerenal azotemia
Diagnosis of salmonellosis
- Faecal culture: requires a minimum of 3 samples!
- Rectal biopsy (culture and PCR)
Combo of 1 and 2 has 60-75% sensitivity
3.PCR: high sensitivity and specificity
Note: cannot distinguish Clostr and Salm based on clinical signs
Aetilology of Clostridiosis
Perfringens A, B, C
Difficile- hospital infections
ABs= predisp
Clostridiosis: clinical signs
Peracute: sudden death without Dx
Acute typhlocolitis
- Depression and anorexia
- Fever, tachycard, tachypnoea
- Colic signs
- Profuse maybe HAEM dx (is this different from salm?)
- Dehydration
- Brick/dirty red mm
Acute laminitis
Clostridiosis Diagnosis
Anaerobic culture
Toxin production seen by ELISA or PCR
Cyathostominosis aetiology
Cyathostomum, Cylicocylus, Cylicostephanus spp
Large colon and caecum may contain 3rd stage larvae in hypobitoic states– emerge when envirnment is favourable
4th stage migrate through LI mucosa
Cyathostominosis Clinical signs
SEASONAL: early spring or following deworming
Severe (maybe fatal)
- Colic signs
- Severe Dx
- Dehydraition
- Sudden weight loss
- SC edema on limbs and ventr abd
- Death
Cyathostominosis diagnosis
Larvae from faeces
Rectal biopsy
Definitive only by biopsy from large colon
Antibiotic associated Dx aetiology
Clinda and lincomycin, TTC’s: experimentally induced enterocolitis
Trimethoprim sulphonamides
Erythromycin
Rifampin
Metronidazole
Changing of PO AB’s
Gram neg bact prolif in the gut flora- disruption
Direct toxicity: irritation, incr secretion, abnormal motility
Antibiotic associated Dx Clinical signs and diagnosis
Usually comes after 2-6 days of the AB therapy
Mild Dx to signs of sever enterocolitis
Similar signs to Salm or Clostr
Diagnosis: AB therapy, ruling out other possible causes
Right dorsal colitis
PHENYLBUT!
Mild to moderate colitis signs usually
- Moderate colic signs
- Cow pat like faeces
Sometimes severe colitis- death
US shows thickened wall of R dors colon
Definitive diagnosis by laparotomy or necroscopy
Cantharidin toxicosis
Toxin of blister beetles
Anorexia, fever, lethargy
Tachycard
Colic signs
Dx
Mixed shock: myocarditis and necrosis
Oral and lingual vesicles and ulcers
Acute tubular necrosis, cystitis: Pollakiuria, haematuria and dilluted urine
Diagnosis is difficult!! (toxins in feed)
Intestinal anaphylaxia (colitis X) Definition and aetiology
Often fatal peracute colitis and endotoxaemia with unknown origin
IgE hypersensitivity in the LI
Intestinal anaphylaxia Clinical signs and diagnosis
Similar to other peracute colitis diseases!
- Severe hypovol and endotoxin shock
- Abd pain
- Profuse Dx
When all tests are negative and no other possible cause
