Colonic and Rectal Disease

Question 1

Obj: Differentiate clinical signs of recto anal diseae from colonic disease and unique clinical signs of specific underlying etiologies

Question 2

Obj: describe the association between proctitis, colonic disease and possible sequela

Question 3

Obj: given PE and imaging findings, recommendd the best treatment for an individual patient with rectoanal disease

Question 4

Obj: list broad differentials for constipation and

Question 5

Obj:

Question 6

Obj:

Question 7

What are the clinical signs of Rectoanal disease?

Answer 7

• Often difficult to distinguish from clinical signs of colonic disease
  
  • Tenesmus
  • Mucoid or hemorrhagic discharge
  • Dyschezia
• Ribbon-like appearance to stool with masses/stricture formation
• Location of blood
  
  • blood coating outside of stool - concern for luminal lesions
  • Intermixed - inflammatory disease

Question 8

What are the different categories of Rectoanal disease?

Answer 8

• Rectal disease
• Anal sac disease
• Perineal disease
• Diseases of storage/defecation

Question 9

Define dyschezia

Answer 9

difficult/painful defecation

Question 10

What is Proctitis? etiologies?

Answer 10

• Rectal mucosal inflammation
• Etiologies:
  
  • Colonic inflammation
  • Foreign body
  • Rectal prolapse

Question 11

What are the clinical signs of Proctitis?

Answer 11

• Tenesmus
• hematochezia
• dyschezia
• concurrent diarrhea suggests colonic involvement

Question 12

How is Proctitis diagnosed?

Answer 12

• Exclusion of other causes
• Histopathology
  
  • most common - lymphoplasmacytic inflammation
  • less common - neutrophilic, eosinophilic, granulomatous

Question 13

What is the treatment for Proctitis?

Answer 13

• Similar to idiopathic IBD/colitis

Question 14

What is a Rectal-anal stricture? etiologies?

Answer 14

• Narrowing of rectal or anal lumen
  
  • usually secondary to circumferential disease
• Etiologies:
  
  • Circumferential neoplasia
  • Rectoanal foreign body
  • Severe IBD
  • Perianal fistula
  • Complication of rectal resection-anastomosis surgery

Question 15

What are the clinical signs of Rectal-anal stricture

Answer 15

• Dyschezia
• Tenesmus w/ narrow ribbon-like stool
• secondary constipation/obstruction

Question 16

How are Recto-anal strictures diagnosed?

Answer 16

• Physical exam (rectal)
• Abdominal ultrasound to ID underlying conditions
• Proctoscopy or colonoscopy for visualization and biopsy

Question 17

What is the treatment for Recto-anal strictures?

Answer 17

• Endoscopic or fluoroscopic-guided balloon dilation or bougienage
  
  • for non-infiltrative disease
  • multiple procedures usually needed
  • intralesional triamcinolone can decrease re-stricture rate
• Surgery - Rectal pull through, resection and anastomosis
• Peri-procedural antibiotics
• Easy digestible diet and laxatives

Question 18

What are the possible complications of Rectal pull-through, resection and anastomosis for Rectal-anal strictures?

Answer 18

• Fecal incontinence
• dehiscence
• re-stricture
• infection

Question 19

What is a Perianal Fistula? etiologies?

Answer 19

• Perianal ulceration and formation of one or more ulcerated perianal sinuses
  
  • secondary to chronic, progressive inflammation
• Etiology: incompletely understood
  
  • Immune-mediated inflammation (T-cell)
  • Associated with dietary intolerance in some cases (e.g. idiopathic IBD)
  • +/- bacterial or anatomic factors

Question 20

What are the clinical signs of a Perianal Fistula?

Answer 20

• Severe perianal pain and dyschezia
• Foul-smelling, mucopurulent discharge from fistulas
• Self-mutilation, tail chasing
• +/- history of chronic diarrhea

Question 21

How are Perianal Fistulas diagnosed?

Answer 21

• PE:
  
  • sedation often required
  • Rectal exam to evaluate for secondary stricture formation, involvement of anal glands, progression into rectal lumen
• +/- Rectal/colonic biopsies to diagnose underlying GI disease

Question 22

What is the treatment for Perianal Fistulas?

Answer 22

• Immunosuppression
  
  • Cyclosporine
    
    • Low-dose ketoconazole may allow dose reduction: Cytocochrom P450 inhibitor
  • Topical Tacrolimus 0.1%
    
    • similar response as cyclosporine
    • difficult to apply if animal is painful
  • Other drugs: Prednisone, azathioprine
• Daily topical cleaning
• Pain management Stool softener
• Diet trial - novel protein or hydrolyzed

Question 23

What is the prognosis for Perianal Fistulas?

Answer 23

• 60-80% improvement after 4wks cyclosporine
  
  • avg complete resolution time of 10-16 in 70-90% of dogs
• Guarded for complete resolution: relapse common

Question 24

What are the possible complications of Perianal Fistula treatment?

Answer 24

• Fecal incontinence
• anal stricture

Question 25

What is Fecal incontinence? Etiologies?

Answer 25

* Inability to retain feces, resulting in involuntary leakage of fecal material * Etiologies: * Reservoir incontinence * disease-related decreased rectal capacity to hold fecal material or decreased compliance * subtotal colectomy * Colonic/rectal fibrosis or severe thickening due to severe IBD * Sphincter Incontinence * disease-related denervation * damage to external anal sphincter

Question 26

What are the clinical signs of Fecal incontinence?

Answer 26

* Usually more severe with sphincter incontinence vs reservoir incontinence * Reservoir: * frequent, voluntary defecation of small fecal balls due to intact external anal sphinter * **awareness** of fecal material presence * Sphincter: * **involuntary** expulsion of fecal material

Question 27

How is Fecal Incontinence diagnosed?

Answer 27

* **Physical Examination** * Reservoir: * frequent posturing to defecate with urgency * +/- concurrent signs of colonic disease * hematochezia, dyschezia * Specific disease processes * Colorectal: neoplasia, constipation, proctitis, colitis * Sphincter: Neurologic * Dribbling of feces from anus, especially with conditions resulting in increased pressure * e.g. coughing, excitement, barking * Decreased anal tone * Specific disease processes: * Cauda equina * Congenital vertebral malformation, meningomyelocele, sacrococcygeal hypoplasia (Manx), vertebral fracture, lumbosacral instability or compression, vascular insult, neoplasia, diskospondylitis * CNS * Infectious (Distemper, FIP) Degenerative myelopathy, neoplasia, vascular insult, trauma * Peripheral neuromuscular Disease * Polyneuropathies, dysautonomia, myasthenia gravis, +.- hypothyroidism * **Complete Neurologic Exam:** * Bladder size, ease of expression, colonic distention, gait, postural reactions, tail tone/anal tone, perineal reflexes, lumbosacral pain, other signs of autonomic nervous system disease * distended, flaccid, easily expressed bladder suggest lesion of the sacral spinal cord, sacral or pudendal nerves, or generalized LMN disease * Usually Normal w/ reservoir incontinence * **Rule-ou**t behavioral/altered mentation/lack of house-training

Question 28

What is the treatment for fecal incontinence

Answer 28

treatment of underlying disease

Question 29

What is Constipation? Etiologies?

Answer 29

* Prolongation of GI transit, typically associated with hardened feces +/- difficult defecation * Etiologies: * Dehydration from systemic disease * Electorlyte abnormalities: hypokalemia, hypo-/hypercalcemia * Endocrine disease: hypothyroidism * Neurologic disease: Breed/anatomic related or acquired (dysautonomia) * Orthopedic or obstructive disease * Prostatomegaly * Lack of exercise * Obesity * Drugs: Opioids * Idiopathic constipation (cats)

Question 30

What is Feline Idiopathic constipation? etiologies?

Answer 30

* Impaired colonic smooth muscle function * abnormalities in colonic motility pacemaker cells * Decreased response to neurotransmitters, membrane depolarization, and electrical field stimulation * No histopathologic lesions of muscle cells/myenteric neurons

Question 31

How does Feline Idiopathic constipation progress?

Answer 31

1. Constipation: prolonged GI transit +/- difficult defecation 2. Obstipation: dilation + loss of function 3. Megacolon: End-stage

Question 32

What are the clinical signs of Feline Idiopathic Constipation?

Answer 32

* Days to months of reduced to absent or painful defecation * Dry, hard feces * +/- Tenesmus

Question 33

How is Feline Idiopathic Constipation diagnosed?

Answer 33

* Rule-out local or systemic predisposing causes * Abdominal Radiographs * Radiographic obstipation: colonic distention 1.5x the length of L7 vertebrae * Clinical obstipation: degree of loss of function

Question 34

What is the treatment for Feline Idiopathic Constipation?

Answer 34

* Hydration * Diet * High fiber if no persistent colonic dilation/loss of function * easily digestible/low residue if persistent colonic dilation * Promotility medication * Cisapride 0.1-0.5 mg/kg q8-12h, * given 30min prior to feeding * Laxatives