Malabsorption Syndromes And Diarrhea - Maratchi

Front 1

Several malabsorption syndromes that present w/out diarrhea are?

Back 1

1. anemia
2. Vitamin deficiencies
3. Osteopenia
4. Menstrual disturbances

Front 2

What are the 3 major luminal defects of malabsorption?

Back 2

1. Defective hydrolysis of fat
2. Defective hydrolysis of protein
3. Impaired solubilization

Front 3

Within Malabsorption Luminal Defects in defective hydrolysis of fat what are the 3 major causes?

Back 3

1. Decreased Lipase
2. Decreased duodenal pH
3. Impaired mixing

Front 4

Luminal Defect: Defective Hydrolysis of Fat

Decreased lipase

Back 4

-results in PANCREATIC INSUFFICIENCY
-ex) 50 yo man w/ multiple spouts of acute pancreatitis, not able to produce lipase, when he consumes fat he is unable to produce the enzyme to hydrolyze fat

Front 5

Luminal Defect: Defective Hydrolysis of Fat

Decreased duodenal pH

Back 5

-results in ZE syndrome
-elevation of gastrin in body

Front 6

Luminal Defect: Defective Hydrolysis of Fat

Impaired mixing

Back 6

-post gastrectomy*
-do not have a stomach, therefore the food does not sit in stomach long enough for it to be affected by enzymes and broken down correctly

Front 7

What are the 2 causes of defective hydrolysis of protein, and the resulting diseases?

Back 7

1. Decreased proteases --> pancreatic insufficiency
2. Absent enterokinase --> congenital enterokinase deficiency

Front 8

What are the 2 causes of impaired solubilization, and the resulting diseases?

Back 8

1. Decreased micelle formation = liver disease, bile duct obstruction, altered enterohepatic circulation, drugs (ex. cholestyramine)
2. Deconjugation of bile salts = bacterial overgrowth

Front 9

What are the 3 major mucosal defects in malabsorption?

Back 9

1. Diffuse mucosal damage
2. Decreased brush border enzymes
3. Transport defects

Front 10

What is the major cause of diffuse mucosal damage, and the resulting diseases?

Back 10

1. Diminished surface area = Celiac disease***, tropical sprue, Whipple's disease, Crohn's disease, enteropathy (AIDS, GVH disease)

Front 11

***Crohn's disease overview:

Back 11

-autoimmune disease of unknown etiology
-when dx Crohn's, biopsy will show areas of "nL" or "skip" lesions followed by portions affected w/ the disease w/ villi disruption
-affects the small bowel esp terminal ileum

Front 12

What is the major delivery defect of malabsorption?

Back 12

1. Lymphatic obstruction which is due to reduced chylomicron and lipoprotein absorption = primary intestinal lymphangeictasisa

Front 13

GUESS WHAT?!?!

Back 13

NOTE SERVICE SAYS NONE OF THE SHIT I JUST MADE CARDS ON ARE SUBMITTED AS TQS!

FML

Front 14

What is the physiology behind diarrhea?

Back 14

-each day 10L of fluid enter jejunum, SI absorbs 90% --> colon receives 1L/day and absorbs 90% -->~100 mL excreted in feces
-diarrhea is defined as 3 or more BMs/day, stool weigh greater than 200gm/day

Front 15

***TQ: What are the 2 types of diarrhea?

Back 15

1. Osmotic --> results from ingestion of poorly absorbed substances that remain in lumen
2. Secretory--> results from disordered electrolyte transport, mechanism is always net secretion of anions or inhib of net Na+ absorpt

Front 16

Osmotic diarrhea

Back 16

-results from the ingestion of poorly absorbed substances that remain in lumen
1. Ingest of poorly absorbed carbs (ex. lactose)
2. Ingest of poorly absorbed ions (Mg, PO4, Sulfate)

Front 17

****TQ: What is the equation for Osmolar Gap?***

Back 17

= 290 mosm/kg - (2x [Na] + [K])

1. >50 mosm/kg = osmotic
2. <50 mosm/kg = secretory

Front 18

Stool analysis of Osmotic Diarrhea

Back 18

1. Low pH - carb malabs (dietary review, lactase assay)
2. High magnesium (inadvertent ingestion, laxative abuse)

Front 19

***TQ: What is ALWAYS the MECHANISM for secretory diarrhea?***

Back 19

-ALWAYS NET SECRETION OF ANIONS OR INHIB OF NET Na+ ABSORPTION

Front 20

What are the 5 major mechanisms of secretory diarrhea and examples of each?

Back 20

1. Infx (E.coli, cholera, campy jejuni, c. diff)
2. Reduction of mucosal SA (intest resection)
3. Inflammation (Crohn's)
4. Dysregulation (diabetes, postvagotomy diarrhea)
5. Circulating Secretogogues (Neuroendocrine tumors-rare)

Front 21

What is Celiac Disease?

Back 21

-Celiac sprue is a chronic malabs disorder of small bowel that is caused by exposure of genetically susceptible individuals to gluten proteins
-prev higher in Western Europe but can affect ANYONE

Front 22

***TQ: Genetic Aspects of Celiac Disease***

Back 22

-genetically inherited disease a/w the HLA locus on the SHORT ARM of chromo 6
1. HLA DQ2 = 95%
2. HLA DQ8 = 5%

Front 23

***TQ: What will an endoscope of a pt w/ Celiac disease show?

Back 23

1. Scalloping - little ridgings (classic of celiac)
2. Flattened villi on histogram

Front 24

What are the typical symptoms of Celiac disease?

Back 24

-diarrhea
-steatorrhea
-wt loss
-anemia

Front 25

What are the atypical symptoms of Celiac diseases?

Back 25

-abd pain
-bloating
-irregular menstrual periods

Front 26

What are the clinical presentations of Celiac disease?

Back 26

1. Dermatitis Herpetiforms - rash is pruritic and vesicular and is symmetrically located
-erythematous, papular vesicles or bullae that burn and itch intensely

Front 27

***TQ: What is the Gold Standard in the Diagnosis of Celiac Disease?***

Back 27

-ENDOSCOPY W/ BIOPSY OF SMALL BOWEL

Front 28

What does the serology of Celiac disease show?

Back 28

1. anti-gliadin ab
2. anti-endomysial ab
3. Tissue transglutaminase abs (MOST SENSITIVE)
***always test for IgA, if IgA deficiency is present then the Abs will not be produced!!!

Front 29

What is the tx of Celiac disease?

Back 29

1. Gluten restricted diet (wheat, rye, barley oats)
2. Ocassionally pts may require steroids or immunomodulators if NOT controlled on diet (help reg immune system and decrease inflammation)

Front 30

What are some diseases a/w Celiacs Disease

Back 30

-micro colitis, RA, IND, dermatitis herpetiformis, thyroid disease, IgA defiency, Psoriasis, small bowel malignancies

Front 31

Vitamin E

Back 31

-fat soluble
-sequalae of deficiency: inc platelet aggregation, hemolytic anemia, neuronal degeneration, decreased DTRs

Front 32

What are the fat soluble vitamins?

Back 32

DEAK***

Front 33

What is the major difference between B12 and folate deficiency?

Back 33

-BOTH are Water soluble
-BOTH are megoblastic anemias

*B12 deficiency causes neurological problems