S2 Ch 9 H/o 1-4

Front 1

138. Effect of Sickle cell on Heart?

Back 1

a. High-output CHF due to anaemia

Front 2

139. Effect of Sickle cell on CNS?

Back 2

a. Stroke

Front 3

140. Effect of Sickle cell on GI tract (3)?

Back 3

a. Gallbladder disease (stones)
b. Splenic infarcts
c. Abdominal Crises

Front 4

141. Effect of Sickle cell on Bones (3)?

Back 4

a. Painful crises
b. Osteomyelitis
c. Avascular necrosis

Front 5

142. Effect of Sickle cell on Lungs (2)?

Back 5

a. Infections
b. Acute chest syndrome

Front 6

143. Effect of Sickle cell on Kidneys (3)?

Back 6

a. Haematuria
b. Papillary Necrosis
c. Renal Failure

Front 7

144. Effect of Sickle cell on Eyes (2)?

Back 7

a. Proliferative retinopathy
b. Retinal Infarcts

Front 8

145. Effect of Sickle cell on Genitalia (1)?

Back 8

a. Priapism.

Front 9

146. Sickle cell inheritance type?

Back 9

a. Autosomal recessive.

Front 10

147. Sickle cell molecular pathophys?

Back 10

a. Results when the normal Hb is replaced by the mutant Hb S.
b. Sick cell disease is caused by inheritance of 2 Hb S genes (homozygous).

Front 11

148. How is Hb S distinguished from Hb A and what is the change that takes place?

Back 11

a. By electrophoresis bc of the substitution of an uncharged valine for a negatively charged glutamic acid at the 6th position of the β-chain.

Front 12

149. Why do reduced oxygen conditions cause problems in sickle cell?

Back 12

a. Reduced oxygen conditions (e.g., acidosis, hypoxia, changes in temp, dehydration, infection) cause the Hb molecules to polymerize, causing RBCs to sickle.
b. Sickled RBCs obstruct small vessels, leading to ischaemia.

Front 13

150. Who are likely to carry sickle cell trait?

Back 13

a. 1/12 African Americans.
b. Also Italians, Greeks, Saudis.
c. These pts are not anaemic and have a normal life expectancy.
d. Screening can ID asymptomatic carriers (SC trait), for whom genetic counseling may be provided.

Front 14

151. Prognosis of Sickle Cell?

Back 14

a. Survival correlates w/the frequency of vaso-occlusive crises- more frequent crises correlate w/shorter lifespan.
b. If there are > 3 crises/yr, the median age of death is 35 yrs.
c. Pts w/fewer crises per year may live into their 50s.
d. In general, SCD reduces life expectancy by 25-30 yrs.

Front 15

152. Clinical feature of Sickle Cell Disease?

Back 15

a. Severe lifelong Haemolytic anaemia!!!!
b. Jaundice, pallor
c. Gallstone disease (very common) - Pigmented gallstones.
d. The anaemia itself is well compensated and rarely transfusion dependent
e. High-output heart failure may occur over time (2º to anaemia) –many adults eventually die of CHF.
f. Aplastic crisis!

Front 16

153. What is Aplastic crisis in sickle cell usually precipitated by?

Back 16

a. Parvovirus B19!!!! Or other viral.
b. Parvovirus B19 reduces; the ability of the bone marrow to compensate

Front 17

154. Treatment of aplastic crisis from Sickle cell?

Back 17

a. Blood transfusion- Pt usually recovers in 7-10 days.

Front 18

155. Symptoms 2º to vaso-occlusion in sickle-cell?

Back 18

1. Painful Crises involving bone!
2. Hand-foot syndrome!
3. Acute Chest syndrome!
4. Repeated episodes of splenic infarctions
5. Avascular necrosis of joints
6. Priapism
7. CVAs
8. Ophthalmologic complications
9. Renal Papillary Necrosis w/haematuria
10. Chronic leg ulcers
11. Abdominal Crisis

Front 19

156. Painful crises involving bone in sickle cell?

Back 19

a. Bone infarction causes severe pain. This is the most common clinical manifestation of vaso-occlusion!
b. The pain is self-limiting and usually lasts 2-7 days

Front 20

157. Hand-food syndrome (Dactylitis)- When does it occur and what is it caused by?

Back 20

a. Often first manifestation of sickle cell disease.
b. Painful swelling of dorsa of hands and feet seen in infancy and early childhood (usually 4-6 months).
c. Caused by avascular necrosis of the metacarpal and metatarsal bones.

Front 21

158. What is Acute Chest syndrome caused by in sickle cell and how does it present?

Back 21

a. Presents w/chest pain, respiratory distress, pulmonary infiltrates, and hypoxia.
b. Due to repeated episodes of pulmonary infarctions.
c. Clinical presentation is similar to pneumonia.

Front 22

159. Result of repeated episodes of splenic infarctions in Sickle cell?

Back 22

a. These lead to autosplenectomy as the spleen is reduced to a small, calcified remnant.
b. The spleen is large in childhood but is no longer palpable by 4 yrs of age.

Front 23

160. Where is avascular necrosis from sickle-cell most common?

Back 23

a. In Hip (↓’d blood supply to femoral head)
b. Shoulder (↓’d blood supply to humeral head)

Front 24

161. Pathophys of priapism in Sickle cell?

Back 24

a. Erection due to vaso-occlusion, usually lasting 30 minutes-3 hours.
b. Usually subsides spontaneously, after urine is passed, after light exercise, or after a cold shower.

Front 25

162. Prophylactic tx of priapism in sickle-cell disease?

Back 25

a. A trial of hydralazine or nifedipine or use of an antiandrogen (e.g., stilbestrol) may prevent further episodes.

Front 26

163. Sustained priapism (lasting >3 hours)?

Back 26

a. Rare (<2%), but is medical emergency.

Front 27

164. Whom does CVAs in sickle-cell disease primarily affect?

Back 27

a. Children.
b. Results from cerebral thrombosis.

Front 28

165. Ophthalmologic complications sickle-cell disease?

Back 28

a. Retinal infarcts
b. Vitreous Haemorrhage
c. Proliferative retinopathy
d. Retinal Detachment

Front 29

166. Renal Papillary necrosis w/haematuria in sickle-cell disease?

Back 29

a. Usually painless
b. Common complication – up to 20% of pts.
c. Seldom requires hospitalization- may cease spontaneously.

Front 30

167. What are chronic leg ulcers in sickle-cell disease due to?

Back 30

a. Vaso-occlusion (↓’d blood flow to superficial vessels) – typically over lateral malleoli.