remediation

Question 1

Hashimoto’s Thyroiditis

Answer 1

• Chronic autoimmune thyroiditis

- the most common cause of hypothyroidism in iodine sufficient areas

Question 2

Clinical characterization of Hashimoto’s thyroiditis

Answer 2

• Gradual thyroid failure, with or without goiter formation
• High serum concentrations of antibodies against thyroid antigens
• Follicular destruction

Question 3

Cause of Hashimoto’s thyroiditis

Answer 3

combination of genetic susceptibility and environmental factors

Question 4

Hashimoto’s : thyroid antigens

Answer 4

Thyroglobulin (Tg)
Thyroid Peroxidase (TPO)
TSH receptor

Question 5

Hashimoto’s: Role of B cells

Answer 5

• Nearly all patients with Hashimoto’s have high serum concentrations of antibodies to Tg and TPO
• TSH receptor antibodies block the action of TSH

Question 6

Hashimoto’s: Role of T cells

Answer 6

• Apoptotic destruction of thyroid cells by activating cytotoxic T cells
• Regulation of the local immune response

Question 7

Pheochromocytoma

Answer 7

• Catecholamine secreting tumors originating from chromaffin cells and the sympathetic ganglia are referred to as “pheochromocytomas” and “catecholamine secreting paragangliomas”
• The concentration of dopamine, norepinephrine, and epinephrine varies in every tumor

Question 8

Clinical Features of Pheochromocytoma

Answer 8

TRIAD: Headache, Palpitations, and Sweating

-life threatening acute hypertensive emergencies

Question 9

Hormones affect on GFR

Answer 9

Norepinephrine: Decrease

Epinephrine: Increase

Endothelin: Decrease

Angiotensin II: neutral (prevents decrease)

Endothelial derived Nitric Oxide: Increase

Prostaglandins: Increase

Question 10

Determinants of GFR

Answer 10

• Glomerular/ Bowman’s Capsule: Hydrostatic Pressure

- Glomerular Capillary Colloid Osmotic: Oncotic Pressure

Question 11

Earliest manifestation of Diabetic Nephropathy

Answer 11

Microalbuminuria

Question 12

Albumin Excretion Rate

Answer 12

> 30 mg/day, <300 mg/day

Question 13

Minimal Change Disease Microscopy

Answer 13

Light Microscopy: typically shows normal glomeruli

Electron Microscopy: shows diffuse effacement of the epithelial cell’s foot processes

Question 14

Pathophysiological findings in Minimal Change Disease

Answer 14

• selective proteinuria, no HTN, preserved renal function
• Most frequent cause of nephrotic syndrome in kids
• Response to corticosteroids
• Primary: Idiopathic
• Secondary: Drugs, Neoplasms, Infections, Allergy

Question 15

G6PD deficiency etiology

Answer 15

Decreased G6PD deficiency leads to Oxidative Injury leads to Hemolysis

Question 16

G6PD pathogenesis

Answer 16

• Reduced Glutathione (GSH)- required to neutralize compounds such as H2O2
• X-Linked recessive (more males affected)
• 2-3 days after exposure -> hemolysis
• GSH -> oxidants “attack” of Hb -> Hb denatures and precipitates -> Heinz bodies -> intravascular hemolysis
• other cells with lesser damage -> extravascular hemolysis

Question 17

G6PD Causes

Answer 17

• Infections (viral hepatitis, pneumonia)
• Drugs like antimalarials, sulfonamides, nitrofurantoin, phenacetin, aspirin
• Vitamin K foods (Fava beans)
• Oxidants that cause both IV and EV hemolysis in G6PD deficient individuals

Question 18

How many nephrons are in each kidney?

Answer 18

1 million

Question 19

How much blood flow does the kidney receive?

Answer 19

~22% CO
1100ml/min
~650 ml of plasma

Question 20

Different steps in Urine Formation

Answer 20

Glomerular Filtration, Tubular Reabsorption, Tubular Secretion

Question 21

Glomerular Filtration

Answer 21

Non selective; averages 20% of renal plasma flow

Question 22

Tubular Reabsorption

Answer 22

Highly variable and selective; most electrolytes and nutritional substances are almost completely reabsorbed

Question 23

Tubular Secretion

Answer 23

Highly variable; important for rapidly excreting some waste products, foreign substances and toxins

Question 24

Chronic Pyelonephritis

Answer 24

Chronic tubulointerstitial inflammation and scarring involve the calyces and pelvis

Question 25

Causes of Chronic Pyelonephritis

Answer 25

- Chronic Kidney Disease - Chronic Obstructive Pyelonephritis (obstruction ->kidney infection -> scarring) - Reflux Nephropathy: from Superimposition of a UTI on congenital vesicoureteral reflux and intrarenal reflux

Question 26

Features of Chronic Pyelonephritis

Answer 26

- Gradual Onset of renal insufficiency - HTN, asymmetrically contracted kidney - Bilateral disease (hyposthenuria manifested by polyuria and nocturia)

Question 27

Thalassemia Syndrome

Answer 27

Caused by inherited mutations that decrease the synthesis of either the alpha or beta globin chains that compose adult hemoglobin

Question 28

Mechanism for Thalassemia

Answer 28

- Decrease HbA formation -> microcytic, hypochromic red cells - Accumulation of unpaired alpha globin chains -> toxic precipitates that severely damage the membranes of red cells and erythroid precursors -> ineffective erythropoiesis

Question 29

When theres decrease hepcidin

Answer 29

iron overload due to excessive absorption of dietary iron

Question 30

Loop of Henle in countercurrent exchange system

Answer 30

serves as multipliers of the concentration gradient

Question 31

Vasa Recta in Countercurrent exchange system

Answer 31

a countercurrent exchanger for maintaining the gradient