HSP PBL

Question 1

HSP most commonly affected patient population?

Answer 1

Children – 90% of cases

Question 2

Common predecessor of HSP?

Answer 2

URI

especially group A Strep

Question 3

Genetic risk for HSP: HLA______.

Answer 3

HLA DRB*01

Question 4

Genetics for decreased HSP: HLA________.

Answer 4

HLA-DRB*07

Question 5

Genetics for increased HSP Nephritis: HLA_______.

Answer 5

HLA-B35

HLA-DQA1 —nephropathy

Question 6

Two conditions associated with HSP:

Answer 6

Familial Mediterranean Fever

Inflammatory Bowel Disease

Question 7

Severe cases of HSPN worrisome for what histologically?

Answer 7

circumferential crescents in glomeruli

infiltration with neutrophils

Question 8

Immunofluorescence looking for what in HSP?

Answer 8

IgA deposition

Question 9

Definition of leukocytoclastic?

Answer 9

destruction of WBCs

Question 10

Presenting symptom in 100% of HSN cases?

Answer 10

palpable purpura

Question 11

Cells in the kidney that proliferate when they endocytose IgAs?

Answer 11

mesangial cells in the glom

Question 12

Why is proliferation of mesangial cells a problem?

Answer 12

Decreased GFR –> decreased filtrate at macula densa –> increased renin secretion –> increased BP

Question 13

NephrOtic syndrome characterized by:

Answer 13

MASSIVE proteinuria

hypoalbuminemia

edema

hyperlipidemia –> hyperlipiuria

Question 14

Nephr-i-tic syndrome characterized by:

Answer 14

hematuria

oliguria

azotemia (elevated serum Cr and BUN)

HTN

Question 15

PE findings in HSP:

Answer 15

low grade fever

palpable purpuric rash

nonmigratory arthritis of joints (usually knees/ankles)

arthralgia

occult blood in stool

Question 16

PE findings when HSP progresses to HSPN:

Answer 16

HTN

edema

pulm edem –> incr RR, possibly rhales

Question 17

Mechanism of proteinuria in HSP:

Answer 17

injury to glom epithelial cells via immune complex deposition and inflammation
–>
effacement of podocytes
–>
increased permeability to large negatively charged molecules (ie. albumin)

Question 18

Mechanism of hematuria in HSP:

Answer 18

immune deposits in small vessels of kidney
–>
inflammation
–>
vascular necrosis
–>
leak blood into urine (RBCs not reabsorbed)

Question 19

Portion of the nephron affected by HSP?

Answer 19

glomerulus–mesangium, subendothelium, subepithelium

Question 20

Review two mechanisms of Angiotensin II activity that elevate BP?

Answer 20

1. contraction of arteriolar smooth muscle
2. stimulate release of aldosterone
   –>
   increased reabsorption of Na+ in distal tubule
   –>
   increased plasma volume