Chrons Disease Flashcards
What is the cause of chron’s disease?
Immune dysregulation and dysbiosis (loss of beneficial microbial input or signal and an expansion of pathogenic microbes) which promotes chronic inflammation
What are the risk factors for chrons disease?
Familiar aggregation
Genetic predisposition (mutation of NOD2 gene, HLA-B27 association)
Tobacco smoke
What is the pathophysiology behind chrons disease?
Immune dysregulation
Dysregulation of IL23TH27 signalling -> unrestrained Th17 cell function -> inflammation -> local tissue damage (oedema, erosions/ulcers, necrosis) -> obstruction, fibrotic scarring, stricture, and strangulation of the bowel.
Mutations of the NOD2 gene protein are likely involved in development of CD
What are the symptoms like in CD?
Intermittent course and episodic acute flared and periods of remission. Clinical creatures differ depending on severity of CD
What are the constitutional symptoms of CD?
Low grade fever
Weight loss
Fatigue
What are the GI symptoms of CD?
Chronic diarrhoea
Lower GI bleeding (uncommon)
Abdominal pain, typically in the RLQ
Palpable abdominal mass in RLQ
Features of CD complications - malabsorption and enterocutaneous or perianal fistulas with abscess formation
Which part of the intestine does CD normally affect?
Terminal ileum and colon
What are extra intestinal symptoms of CD?
Joints
Eyes
Liver/bile ducts
Urogenital system
Oral mucosa
Skin
What disease is involved in the joint for CD?
Enteropathic arthritis (type of arthritis that occurs in IBD)
What diseases are involved in the eyes for CD?
Uveitis
Iritis
Episcleritis
What disease is involved in the liver/bile ducts for CD?
Cholelithiasis
What disease is involved in the urogential system for CD?
Urolithiasis
What disease is involved in the oral mucosa for CD?
Oral aphthae
What diseases are involved in the skin for CD?
Erythema nodosum
Pyoderma gangrenosum
What is the diagnosis for chrons disease?
Endoscopy, cross sectional imaging and lab studies are required for initial evaluation of suspected CD
What is the purpose of cross sectional imaging for CD?
Establish locations and severity of disease
Identify complications eg abscess
What is the purpose of lab studies for CD?
Rule out differential diagnosis of CD eg infectious gastroenteritis
Assess and monitor disease activity
what are the supportive findings of an ileocolonoscopy?
Skin lesions
Cobblestone sign (inflamed edematous sections interspersed with deep ulcerations that resemble cobblestones)
What are the supportive findings worth a cross sectional enterography?
Edematous thickening of intestinal wall
Creeping fat - excessive mesenteric fat around the affected segments of bowel
Which other diagnostic studies can be performed for CD?
Ultrasound of the abdomen
Which lab studies can be done to rule out differential diagnosis of CD?
Stool analysis to identify Ova, cysts
Serology - increased ACSA in CD
Which lab studies ca be performed to monitor disease activity?
Fecal calprotectin are non invasive markers of intestinal inflammation
Inflammatory markers CRP, ESR, platelets. Increased thrombocytes is an indicator of active disease
Which lab tests can be done to identify complications?
Complete metabolic panel - identify malnutrition, end organ damage
CBC - iron studies, B12, folate to evaluate for anaemia and micronutrient deficiency
What is the pathology of CD?
Transmural inflammation
Non caseating granulomas
Giant cells
Distinct lymphoid aggregates of the lamina propria
Creeping fat
Hypertrophic lymph nodes