Hematology

Question 1

VWD How common is the disease?

Answer 1

• most common inherited bleeding disorder, with an estimated prevalence cited at 1 : 100 to 1 : 10,000 (Aut Dominant)
• A family history of either VWD or bleeding symptoms and confirmatory laboratory testing are also required for the diagnosis of VWD.

Question 2

VWD How does it present?

Answer 2

1. mucosal bleeding ( like platelet defects) -Epistaxis, menorrhagia
2. Surgical bleeding,-dental extractions or adenotonsillectomy,
3. Severe type 3 VWD - joint bleeds.

Note:

Most patients will have a family history of bleeding.

-Symptoms do not correlate well with VWF levels.

Question 3

VWD What 5 test can you do to Dx VWD?

Answer 3

Question 4

VWD How do you classify VWD?

Answer 4

Question 5

VWD How do you Rx VWD?

Answer 5

Question 6

DIC How do you differentiate DIC from hemorrhagic disease of the newborn due to vitamin K deficiency?

Answer 6

DIC

1. Coag tests: Raised INR + PT, PTT and Thrombin times, FDP’s (D-dimers) appear in the blood
2. Consumption of factors 2,5,8 and fibrinogen
3. Blood film:
   a. RBC’s -fragmented, burr- and helmet-shaped RBC’s (schistocytes)
   b. Low platelets,

Vit K deficiency high INR

Question 7

DIC How do you treat it?

Answer 7

1. Treat the trigger that caused DIC
2. Restore normal homeostasis by correcting the shock, acidosis, and hypoxia that usually complicate DIC.
3. If needed: Blood components :
   a. Platelet infusions
   b. Cryoprecipitate (for hypofibrinogenemia) and/or
   c. FFP (for replacement of other coagulation factors and natural inhibitors).

Question 8

Anttithrombin 3 deficiency What role does antithrombin play?

What is its etiology?

Answer 8

• Its a natural anticoagulant that inhibits:
  1. thrombin - factor 2a
  2. factor 10a, and 9a

Etiology:

Its either genetically inherited Aut Dominant or Acquired

Question 9

Antithrombin 3 deficiency What are the 3 groups of causes?

Answer 9

1. Hematology:

a. DIC - the ongoing coagulation and fibrinolysis consumes procoagulant and anticoagulant factors
b. Acute thrombosis can reduce AT levels transiently

2. Organ problems:

a. Liver disease (primarily cirrhosis) less synthesis of procoagulant and anticoagulant factors, including AT
b. Nephrotic syndromes may be associated with urinary losses of AT as well as other anticoagulant factors including protein S and protein C

3. Iatrogenic:

a. ECMO and hemodialysis-reductions in plasma AT levels
b. Surgery and trauma may be accompanied by a variety of prothrombotic and bleeding effects and modest fall in AT levels
c. Drugs: Asparaginase therapy reduces synthesis of proteins that contain the amino acid asparagine, including AT. Asparagine-containing chemotherapy regimens for acute lymphoblastic leukemia (ALL) are associated with an increased thrombotic risk, which may be due to reduced AT in combination with other factors such as glucocorticoid administration, immobilization, and/or the presence of a central venous catheter.

Question 10

TEC What is it and how common is it?

Answer 10

-It is a syndrome of severe, transient hypoplastic anemia, most common acquired red cell aplasia occurring in children.

Question 11

TEC Epedimiology?

What age group and what is incidence?

Answer 11

• previously healthy children between 6 mo and 3 yr of age; (most >12 mo at onset)
• The annual incidence 4/100,000 children,

Question 12

TEC etiology?

What Ig’s are incolved?

Hwo is it transmitted?

What is most common trigger?

Answer 12

• linked to immunoglobulin (Ig) G, IgM, and cell-mediated mechanisms.
• Familial cases ? hereditary component.
• often follows a viral illness, although no specific virus has been consistently implicated.

Question 13

TEC Clinical course

How soon after the trigger does it occur?

How long does it last?

Answer 13

1. ONSET: 2wks-2mos after viral URTI or GI illness
2. PROGNOSIS:
   a. Spontaneous recovery after 1-2mos;
   b. transfusions may be necessary for severe anemia with no signs of recovery

Question 14

TEC What are the lab features?

Answer 14

Lab features:

1. Blood Smear: non-specific,

a. RBCs have age-appropriate characteristics

b. WCC: +/- atypical lymphocytes & 20% neutropenia

b. Platelets: N or increased platelets
d. Other: normal MCV, Normal ADA, normal HbF

(vs diamond-blackfan -> fetal RBC characteristics)

Question 15

TEC In what 5 ways does TEC differ from Diamond Blackfan Syndrome (DB)?

Answer 15

1. Age: DB starts by 6 months (younger than TEC)
2. DB has increased Hb F and MCV
3. DB has Increased antigen I and increased RBC adenine deaminase (ADA)