Pathology Flashcards
What are the major diseases causing malnutrition?
Celiac disease Tropical Sprue Whippel's disease Lymphangeactasia Crohn's enteritis
Define malabsorption
A condition characterized by suboptimal absorption of fat, fat- soluble and other vitamins, proteins, carbohydrates, electrolytes and minerals, and water.
What functions, when affected, would lead to malabsorption?
Intraluminal digestion
Terminal digestion
Transepithelial transport
Describe the clinical presentation of Malabsorption
Abnormal greasy, yellow/gray stools
Weight loss
Anorexia
Abdominal distention
Why can a patient with celiac disease be misdiagnosed?
can present with extra GIT symptoms
What is another name for celiac disease?
Celiac Sprue
Gluten Sensitive Enteropathy
Epidemiology of Celiac disease
Caucasians
Pathophysiology of Celiac Disease
Cell mediated immunity against the gluten [alcohol soluble protein component [Gliadin]]
Gluten taken into small intestine → ↑ intraepithelial cytotoxic T cells and ↑ large number of lamina propria T-helper cells that are sensitized to gliadin → cytokine release → damage to the intestinal enterocytes. HLA DQ XIB heterodiamer genetic trend → confer susceptibility through interaction with gliadin.
Hypothesis behind the immune reaction in Celiac Disease
Gliadin cross- react with a fragment protein
The E1b protein of type 12 adenovirusàraise possibility that this disease might be resulted from exposure to this virus earlier in life.
Gross morphology of Celiac Disease
Flat mucosa [Loss of normal villous architecture → atrophy of mucosa]
Microscopic features of Celiac Disease
Surface epithelial layer is packed by T- lymphocytes and lamina propria
Crypts are hyperplastic, ↑ in number, tortuous with ↑ mitotic figures → overall mucosal thickness remains the same
Loss of microvilli + brush borders
What are the symptoms of Celiac Disease
Diarrhea Unexplained weight loss Abdominal pain Failure to thrive Skin Rash Arthritis Unexplained malaise and fatigue
What does Celiac disease increase the risk of?
T-cell lymphoma
GI carcinoma
Breast carcinoma
What genetic factors are associated with Celiac Disease?
HLA B8
HLA DR3-DQw2
What is a diagnostic finding of Celiac disease?
Mucosal mosiac changes seen on endoscopy
Epidemiology of Tropical Sprue
Tropics [Carribean], Central Africa, India, Southern Asia, South and Central America
Occurs as endemic and epidemics
Patholophysiology of Tropical Sprue
Same as celiac deficiency → folate and vitamin B12 deficiency → megaloblastic anemia
Symptoms of Whipple’s disease
Steatorrhea Lymphadenopathy Malabsorption Diarrhea Arthritis [often] Encephalopathy [occasionally]
What stain is used in Whipple’s disease?
PAS stain
What is bacterial organisms are implicated in Tropical Sprue?
enterotoxigenic organisms [E. coli and Haemophilus in. ]
Microscopic features of Tropical Sprue
Bacteria-laden macrophages and lipid pools in mucosa
What would a culture from a patient with Whipple’s disease show?
Tropherhyma whippli bacilli within macrophages
[PAS Stain]
What is the treatment for IBD?
Immunosuppressive therapy
What is the possible etiology of IBD?
alteration in usual steady state between immune system and host defenses that maintain integrity of mucosa and down-regulate inflammation.
Epidemiology of IBD
Increased prevalence
Occurs at an early age
Low mortality
Family history is common
Epidemiology of Ulcerative Colitis
Onset: 15-40 yrs,
Second peak: 50 - 80 yrs.
Men = women
Variable course and severity
What are the local complications of Ulcerative Colitis?
Perforation Toxic Megacolon Hemorrhage Inflammatory polyps [pseudopolyps] Colonic carcinoma
What are the symptoms of Ulcerative Colitis?
Relapsing blood mucoid diarrhea [stringy mucus]
Pain/Cramps [relieved bu defecation]
Disease course lasts days/month
Remission for months/years
What are the systemic complications of Ulcerative colitis?
Uveitis Ankylosing Spondylitis Sclerosing cholangitis Erythema nods Malnutrition Arthritis Pyoderma gangrenosum
What are the gross findings of Ulcerative colitis?
Diffuse mucosal inflammation confined to the colon [mucosa is hemorrhagic, granular, friable]
Rectum involvement in 95%; can extend proximally, in a continuous fashion, aCrypt s far as the cecum.
Back wash ileitis occur in continuity with active pancolitis
Extensive ulceration along bowel axis
Pseudopolyps and flat mucosa
Normal wall thickness and normal serosa
What are the microscopic findings of Chronic Ulcerative colitis?
Architectural distortion Basal plasma cells Chronic inflammation in lamina propria Paneth cell metaplasia Pseudopolyps
What are the microscopic findings of Acute Ulcerative colitis?
Crypt abscesses/Cryptitis
Ulceration
