Day 6 - Gastrointestinal diseases Flashcards
Gastric ulcers in newborn foals
Glandular mucosa and greater curvature affected
Tx: H2 antagonists (ranitidine), sucralfate
Sucklings and weanlings
Lesions along the lesser curvature on the squamous mucosa
Gastroduodenal ulcer disease in foals
Diffuse inflammation to severe ulceration and thickening of duodenal wall
- Delayed gastric emptying
- Gastric or duodenal rupture
Yearlings and adult horses
On the squamous mucosa along the margo plicatus
General treatment of gastric ulcers
- Proton pump inhibitors: omeprazol
- H2 antagonists: Rantidine
- Sucralfat
Acute gastric dilation and impaction - pathogen (7)
– Fermentation: gas, volatile fatty acids, lactate
– Fluid influx
– Gastric dilation, colic
– Pressure on diaphragm, compromised respiration
– Decreased venous return
– Hypovolaemic shock
– Gastric rupture
Acute gastric dilation and impaction - CS
- Sudden onset, fast progression
- Severe, continuous colic
- Decreased GI motility
- Negative rectal findings
- Diagnostic nasogastric tubing
- Haemoconcentration, Hyperlactataemia
- Enlarged stomach on ultrasound
Acute gastric dilation and impaction - Dx
- Nasogastric tubing
- Ultrasonography
Acute gastric dilation and impaction - Tx (3)
- Spasmolytics, analgesics
- Stomach tubing and lavage
- IV fluid therapy
Gastric parasites
Gasterophilosis
Draschia megastoma
Ivemectrin
Spasmodic colic - Aetiology
- Nutritional deficiencies
- Cold water
- Weather
- Parasites
- Steneous excercise
Spasmodic colic - Pathogenesis
- Smooth muscle spasms
- Hypermotility
- Vagotonia (parasymp.)
Spasmodic colic - CS
Mild colic signs, borgormi, gas, loose faeces
Spasmodic colic - DD (7)
- Tympany (primary, secondary)
- Impaction
- Ileus
- Acute gastric dilation
- Acute enteritis
- Pregnancy colic
- Urinary colic (kidney, ureter, urethra)
Spasmodic colic - Tx
- Spasmolytics (butylscopolamine)
- NSAIDs
- Hand walking
- Activated charcoal or other absorbents via NG tube
- IV fluids
Proximal enteritis - aeti
- unknown
- clostridium, fusobact, salmonella
- sudden diet change
Proximal enteritis - Pathogen
Increased secretion
* cAMP, cGMP system, Calcium system
* Na+ and Cl- to gut lumen: Water follows ions
* Bacterial toxins
* Protein rich fluid secreted to intestinal lumen
Initially hyperperistalsis, then functional ileus
* Serositis, peritonitis
* Activation and migration of inflammatory cells
* Intestinal distention, Endotoxins
Decreased absorption
* Marked fluid and electrolyte loss
* Haemoconcentration, hypovolaemia, decreased tissue perfusion, oliguria, haemorrhages, Yellowish bands
* From stomach to large intestine
* Degeneration, necrosis, sloughing
* Neutrophilic infiltration (propria, submucosa, mucosa) * Haemorrhages on serosa and in muscularis
* Haemorrhagic, fibrinonecrotic DPJ
Hepatic changes
Peritoneal fluid
* Higher total protein (TP), than in mechanical ileus
* increase of TP relative to nucleated cell count
* Leakage of blood or plasma into abdominal cavity
* No significant leukocyte chemotaxis
Proximal enteritis - CS
- colic signs, reflux
- Fever
- Decr peristaltic sounds
- Rectal: distended SI loops
Proximal enteritis - Clinical pathology
- PCV, TPP, lactate: ↑
- CBC – WBC count ↑↓↔
- Hypo; Na, Cl, K
- Prerenal azotaemia
- Increased AST, AP, GGT → liver damage
- Metabolic acidosis
- Abdominocentesis; yellow tube
Proximal enteritis - Tx (8)
- Supportive
- Nasogastric tubing
- Fluid therapy: Crystalloids, Ringers and colloids (HES)
- Antibiotics → Dysbacteriosis in large intent Penicillin, metronidazole, – Gentamicin, enrofloxacin (Gr-)
- Anti-inflammatory and analgesic therapy
– Flunixin meglumine, Butorphanol - Prokinetic drugs: Lidocaine (best), Metoclopramide
- Parenteral feeding
– Dextrose, amino acids, lipid, isotonic solution
– Blood glucose checks, insulin
Direct causes of diarrhoea
- Increased faecal water and electrolyte content
- Hypersecretion and malabsorption
Indirect causes of diarrhoea (5)
- Acute colonic inflammation causes increased prostaglandin release –> hypersecretion
- Some enterotoxins bind to secretory receptors
- VFA and sodium malabsorption causes increased permeability in the large colon
- Abnormal microflora produces a large amount of dissolved metabolites
- Altered intestinal motility forward content faster
Sequale of diarea
- Significant and fast loss of Na+, K+, Cl- and HCO3-
- Loss of plasma to intestinal lumen in severe cases
- Dehydration, metabolic acidosis, shock, renal insufficiency, death
Acute colitis - aeti
- Bacterial: Salmonellosis, Clostridiosis, Neorickettsiosis
- Parasitic: Strongylosis, Cyathostominosis, Anoplocephalosis
- Toxic: Antibiotic-associated diarrhoea, Cantharidin toxicosis
- Miscellaneous: Intestinal anaphylaxia, Carbohydrate overload, Sand enteropathy
Salmonellosis - Type and pathogen
S. enterica var. typhimurium, var. agona (stress, nosomosis, zoonosis)
Enterotoxin - POG synthesis - incr secretion - diarrhoea
Salmonellosis - CS
Colic signs
Profuse, watery, malodorous diarrhoea
Dark red, dirty red, purple mucous membranes, prolonged CRT
Rectal: Gas
Acute laminitis
Salmonellosis - clinical pathology
- PCV>60%, decreased TPP
- Leukopenia, neutropenia
- Thrombocytopenia
- Hyponatraemia, hypochloraemia, hypokalaemia
- Metabolic acidosis
- Praerenal azotaemia
Salmonellosis - Dx
- Culture
- Faeces
-Rectal biopsy - Combination of these two: 60-75% sensitivity
- PCR
Cyathostominosis
Aetiology
* Cyathostomum, Cylicocyclus, Cylicostephanusspp
* 3rd stage larvae may stay in hypobiotic state in caecal and large colon wall
* Larvae emerge in response to favourable conditions
* 4th stage larvae migrate through large intestinal mucosa
Clinical signs: seasonal
* Early spring (northern hemisphere)
* Following deworming
* Signs of severe, sometimes fatal typhlocolitis
* Colic signs. Severe diarrhoea
* Dehydration. Sudden weight loss
* Subcutaneous oedema on limbs and ventral abdomen * Death
Diagnosis
* Isolation of larvae from faeces
* Rectal biopsy
* Definitive diagnosis: biopsy from large colon
Antibiotic-associated diarrhoea
Aetiology
* Clindamycin, lincomycin, tetracyclins
* Trimethoprim-sulfonamide combinations tetracycline - no dia
* Erythromycin. Rifampin. Metronidazole
Clinical signs, diagnosis
* Mild diarrhoea or signs of severe enterocolitis
* Similar signs to salmonellosis or clostridiosis
* Diagnosis
- Antibacterial therapy
- Ruling out other possible causes
Right dorsal colitis - Dx
- Appears after phenylbutazone administration
- Signs of mild to moderate colitis
- Moderate colic signs
- Cow pat like faeces
- Sometimes severe colitis, death
- Gastric ulceration
- Trans abdominal ultrasonography
- Definitive diagnosis by laparotomy or necropsy
Cantharidin toxicosis
- Cantharidin: toxin of blister beetles (Epicautaspp) →
- 6-100 dried beetles might be lethal
- Anorexia, lethargy, fever, tachycardia
- Colic signs
- Diarrhoea
- Mixed shock (myocarditis and necrosis)
- Oral, lingual vesicles and ulcers , urinary tract signs
- Pollakiuria, haematuria, diluted urine (acutetubular necrosis, cystitis)
- Diagnosis is difficult (detection of cantharidin in feed)
