Lecture 15: Pediatric GI Disease (Tutorials)

Question 1

What is significant about transglutaminase antibodies (tTG)?

Answer 1

Elevated levels of tissue transglutaminase antibodies (tTG)
Significant because transglutaminase degrades gladin
Elevated levels of tTG = celiac disease

Question 2

What are endoscopic findings for celiac?

Answer 2

Scalloping and nodularity

Question 3

What are symptoms of celiac?

Answer 3

1. failure to thrive/loss of weight/abdominal distention
2. diarrhea
3. dermatitis
4. hepatitis
5. arthritis
6. osteopenia
7. delayed puberty

Question 4

What is associated with celiac disease?

Answer 4

T1DM
Thyroiditis
(autoimmune)

Question 5

What is the pathogenesis of celiac disease?

Answer 5

Genetic predisposition
-HLA-DQ2 and DQ8
-association of HLA association
-10% of patients have an affected first degree relative
Exposure of gluten
HLA-DQ2 and DQ8 are NECESSARY but not sufficient

Question 6

How are T cells activated in celiac disease?

Answer 6

Presentation of modified gliadin peptide in context of HLA-DQ2/8 leads to activation of CD4 lamina propria T cells
Gliadin specific T cells have TH1 functional phenotype with high secretion of IFN-gamma

Question 7

What is the pathophysiology of sequelae of celiac disease?

Answer 7

Malabsorption of nutrients like iron, folate, and calcium

Increased permeability may permit entry of toxins

Question 8

What does EMA stand for?

Answer 8

Antiendomysial antibodies

Question 9

What is an endomysium?

Answer 9

Means within the muscle

A wispy layer of areolar connective tissue that sheaths each muscle fiber

Question 10

What are the two antibodies that we look for in celiac disease?

Answer 10

1. EMA (IgA) or antiendomysial antibodies
2. TTG transglumitidase
   TTG is breakdown of gluten

Question 11

What is the histological characteristic in celiac disease?

Answer 11

Loss of villi
Increase in number of lymphocytes
But can also have variable appearance (if you have gluten
Free diet)

Question 12

What is diagnostic of eosinophilic esophagitis?

Answer 12

Allergies + esophagitis (difficulty swallowing) = eosinophilic esophagitis

Question 13

What is the spectrum of eosinophilic gasteroenteropathies due to allergies?

Answer 13

1. Eosinophilic esophagitis
2. Eosinophilic gastroenteritis
3. Allergic Protocolitis

Question 14

What are the characteristics of eosinophilic esophagitis?

Answer 14

Presents with symptoms similar to gastroesophageal reflux disease (GERD)
Unresponsive to aggressive acid blockade, responsive to removal of food antigen
Can see
i. asthma
ii. Rhinitis
iii. exczema
Elevated IgE
Responsive to coriticosteroids and restriction diet
Can see WHITE PLAQUES and eosinophils

Question 15

What are the characteristics of allergic protocolitis?

Answer 15

<1 yo, seen in 3rd world, more men than women
Clinical symptoms include
	i. blood streaked stools
	ii. diarrhea
	iii. mild abdominal pain	
	iv. normal weight gain
Lab features
	i. fecal leukocytes
	ii. mild peripheral eosinophilia
Can be provoked by cow’s milk protein
Soy milk
From breast milk as well
So this is a milk etiology!!

Question 16

What are the two diseases with eosinophils in esophagus?

Answer 16

1. eosinophilic esophagitis

2. GERD

Question 17

What are the key characteristics of eosinophilic gastroenteritis?

Answer 17

Etiology unknown
Eosinophilic infiltrate at various sites of GI tract
Exclusion of other GI eosinophilia
Most difficult to treat
Most commonly in gastric antrum!

Question 18

What is eosinophilia in the GI tract associated with?

Answer 18

Parasites
IBD
Neoplastic
Deficiencies of vitamin E, selenium

Question 19

What are the etiologies of IBD?

Answer 19

1. genetic predisposition
2. mucosal immune system
3. environmental triggers

Question 20

Between crohns and ulcerative colitis, which has granulomas?

Answer 20

Crohns has granulomas (pathognomonic)
Ulcerative affects the rectum!
UC starts in rectum and goes
proximal

Question 21

If you have weight loss or growth failure, what IBD is it?

Answer 21

More likely CD because small intestine is involved

Question 22

What are the histological features of colitis?

Answer 22

1. Crypt injury
2. Neutrophilic infiltrate
   
   • lamina propria, cryptitis, crypt abscess
3. erosions
4. ulcers

Question 23

What is phosphoda?

Answer 23

Used to clean out colon

Can cause histological feature changes

Question 24

What is PMA?

Answer 24

Periodic motor activity

Question 25

What is chronic granulomatous disease?

Answer 25

Group of hereditary diseases caused by failure of phagocytic cells forming ROS used to kill pathogens
Inability to produce H2O2, hydrogen peroxide
Stomatitis, oral ulcers, esophageal gastric strictures
Can mimic celiac and IBD!!

Question 26

What is a disease associated with an inability to produce H2O2?

Answer 26

Chronic Granulomatous Disease

Question 27

What are the key characteristics of X-linked agammaglobulinemia?

Answer 27

Absence of plasma cells

Recurrent bacterial infections after 9 months of

Question 28

What is the takehome point for case 4?

Answer 28

Immunodeficiency can mimic celiac disease and IBD like changes
Especially with younger patients

Question 29

What does IgA deficiency associate itself with?

Answer 29

Celiac disease