Organ System Pearls

Question 1

Sudan Stain

Answer 1

Looking for Fecal fat - Malabsorption syndromes

Question 2

Electrical Alternans

Answer 2

Varying QRS amplitudes due to cardiac tamponade

Heart is beating against a bag of fluid

Question 3

Atopic Dermatitis

Answer 3

May have mutations in Filaggrin or other epidermal proteins which impair the skin’s barrier function

Question 4

Factor V Leiden mutation

Answer 4

G to A DNA point mutation
Arg506Gln mutation near the cleavage site

Resistant to degradation by Protein C

Question 5

Prothrombin Gene mutation

Answer 5

Mutation in 3’ untranslated region
Prothrombin 20210A
Increased production of prothrombin

Question 6

Uterus Lymphatic Drainage

Answer 6

Para-Aortic

Question 7

Popliteal Lymph Nodes

Answer 7

Dorsolateral Foot

Posterior calf

Question 8

IMA Lymph Nodes

Answer 8

Colon from Splenic Flexure to Upper Rectum

Question 9

Internal Iliac Nodes

Answer 9

Lower Rectum to Anal Canal
Bladder
Vagina (Middle Third)
Cervix
Prostate

Question 10

Kidneys Lymphatic Drainage

Answer 10

Para-Aortic

Question 11

Mediastinal Nodes

Answer 11

Trachea and Esophagus

Question 12

Celiac Nodes

Answer 12

Liver
Stomach
Spleen
Pancreas
Upper Duodenum

Question 13

SMA Nodes

Answer 13

Lower Duodenum
Jejunum
Ileum
Colon to Splenic Flexure

Question 14

Marginal Zone of Spleen

Answer 14

Contains macrophages and APCs

Decreased opsonizing ability (C3b) post-splenectomy

Question 15

B2-Microglobulin on which MHC?

Answer 15

MHC I

Loads antigen peptides in RER and delivery via TAP

Question 16

MHC II loads antigen where?

Answer 16

Antigen loaded following release of invariant chain in an acidified endosome

Question 17

CD56 and CD16

Answer 17

NK Cells
Use perforins and granzymes to induce apoptosis

(NOT THE SAME AS CD8+ CELLS!!!)

Question 18

IPEX

Answer 18

Mutation in FoxP3

Enteropathy, Endocrinopathy, Nail Dystrophy, Dermatitis, and/or other autoimmune dermatologic conditions

Question 19

Thymus Independent Antigens

Answer 19

Antigens without a peptide component
EX: LPS form Gram- bacteria

Weakly immunogenic, require boosters and conjugated vaccines

Question 20

Neutrophil Chemoattractants

Answer 20

C5a, LTB4, IL-8, fMet

Question 21

Factor H

Answer 21

Blocks alternative pathway. Expressed on HOST cells to prevent complement mediated lysis

Question 22

Membrane Attack Complex

Answer 22

Defends against Gram- bacteria

Question 23

C1 Esterase Inhibitor Deficiency

Answer 23

Unregulated kallikrein being converted to bradykinin

Decreased C4 Levels

Question 24

IL-1

Answer 24

Fever
Also stimulates osteoclasts - sex hormones put the brakes on osteoclasts
IL-1 secreted in Multiple Myeloma leading to lytic bone lesions

Question 25

Lactoferrin

Answer 25

A protein found in secretory fluids and neutrophils that inhibits microbial growth via IRON CHELATION

Question 26

Pyocanin

Answer 26

Virulence factor of Pseudomonas that generates ROS to kill competing microbes

Question 27

CD80/86

Answer 27

On Macrophages - same thing as B7 which binds CD28 on T-Cells for APC

Question 28

False Diverticula

Answer 28

Occur where Vasa Recta perforate Muscularis Externa

Zenker’s, Diverticulosis (most diverticula are false)

Question 29

HIT

Answer 29

Heparin Antibodies directed against Platelet Factor 4

Question 30

Peutz-Jeghers Syndrome (PJS)

Answer 30

Mutations in Serine/Threonine Kinase 11 (STK11) gene on chromosome 19