Question 1

Explain how disseminated intravascular coagulation is not a primary disease state.Correlate etiology, pathophysiology, and laboratory analysis in your response.

Accepted Answer

The answer of Explain how disseminated intravascular coagulation is not...

Question 2

Explain the inheritance pattern of the following disorders, and explain how this contributes to the clinical manifestations of the disorders:
a.Hemophilia A
b. Hemophilia B
c. von Willebrand’s disease
d. Bernard-Soulier syndrome

Accepted Answer

The answer of Explain the inheritance pattern of the following...

Question 3

What plasma factor levels can be expected in a female carrier of F-VIII or F-IX deficiency?

Accepted Answer

Female carriers of F-VIII or F-IX deficiency have approximately 50% of the normal plasma levels of the deficient factor due to the X-linked inheritance pattern. They have one normal X chromosome and one mutated X chromosome, so they produce approximately 50% of the factor level that a non-carrier individual would produce.

Question 4

Which of the following laboratory assays would be useful in identifying presence of primary fibrinolysis?

Accepted Answer

FDP (fibrin degradation products) and D-dimer are both markers of fibrinolysis. Elevated levels of both would indicate the presence of primary fibrinolysis. Fibrinogen and platelet count are not specific to fibrinolysis, while plasmin is an enzyme involved in fibrinolysis and would not necessarily indicate the presence of primary fibrinolysis.

Question 5

A known hemophiliac has developed an inhibitor.The physician in charge of his care wants to know how much inhibitor is present so that he can properly treat him.What two lab tests would he have to order to assess this?

Accepted Answer

Factor VIII: C level test measures the level of factor VIII in the patient's blood, which gives an indication of the severity of hemophilia. The Bethesda titer test helps in identifying the presence of inhibitors and measures the levels of antibodies in the blood that can neutralize factor VIII. Therefore, these two tests can help the physician in charge of his care to assess the presence of inhibitors and appropriately treat him.

Question 6

What test(s) would help differentiate this disorder from other acquired disorders?

Accepted Answer

All of the tests listed can help differentiate acquired von Willebrand syndrome from other acquired disorders. D-dimer is a marker of fibrinolysis, which is increased in acquired von Willebrand syndrome. Liver enzymes are elevated in liver disease, which can also cause acquired von Willebrand syndrome. von Willebrand's factor is decreased in acquired von Willebrand syndrome.

Question 7

Explain how liver disease can be differentiated from DIC through laboratory test analysis.

Accepted Answer

The answer of Explain how liver disease can be differentiated...

Question 8

An advantage of prenatal diagnosis by genotypic analysis for hemophilia over phenotypic analysis is:

Accepted Answer

Genotypic analysis is not affected by ABO blood type, making it a more reliable method for diagnosing genetic conditions like hemophilia compared to phenotypic analysis.

Question 9

How does von Willebrand's disease differ from Bernard-Soulier syndrome? Correlate the pathophysiology of both disorders in your response.Name at least two laboratory test methods by which to differentiate between the two.

Accepted Answer

The answer of How does von Willebrand's disease differ from...

Question 10

Which is the most common F-VIII mutation in patients with a severe phenotype (occurring in almost 50% of patients)?

Accepted Answer

Inversion mutation of intron 22 is the most common F-VIII mutation in patients with a severe phenotype, occurring in almost 50% of patients. This mutation results in a reduced level of functional F-VIII due to abnormal splicing of exons. The other options listed are also known mutations in F-VIII, but they are not the most common in patients with a severe phenotype.

Question 11

George Jones is admitted to the hospital with abdominal pain.Upon physical examination, the attending physician notices a yellow ring around George's green eyes.George has a significant swelling in his abdomen, and has been suffering from swollen joints for the last month.The physician runs a battery of labs.The results are below: \(\begin{array}{|l|l|l|}
\hline\text { TEST } & \text { George Jones } & \text { Reference Range } \
\hline \text { PT } & 16.8 \mathrm{sec} & 11-13 \mathrm{sec} \
\hline \text { INR } & 3.85 & \text { NA } \
\hline \text { APTT } & 71 \mathrm{sec} & 23-32 \mathrm{sec} \
\hline \text { BT } & 5 \mathrm{~min} & 2-6 \mathrm{~min} \
\hline \text { Fibrinogen } & 275 \mathrm{mg} / \mathrm{dL} & 200-400 \mathrm{mg} / \mathrm{dL} \
\hline \text { Factor X } & 22 \% & >50 \% \text { activity } \
\hline \text { Factor II } & 21 \% & >50 \% \text { activity } \
\hline \text { Factor VII } & 23 \% & >50 \% \text { activity } \
\hline \text { Factor V } & 28 \% & >50 \% \text { activity } \
\hline \text { Factor XII } & 95 \% & >50 \% \text { activity } \
\hline  \text { Factor XI } & 99 \% & >50 \% \text { activity } \
\hline \text { Factor IX } & 30 \% & >50 \% \text { activity } \
\hline \text { RIPA } & 95 \% & >50 \% \text { activity } \
\hline \text { AST } & \text { Elevated } & \text { Normal } \
\hline \text { ALT } & \text { Elevated } & \text { Nomal } \
\hline \text { GGT } & \text { Elevated } & \text { Normal } \
\hline \text { TBL } & \text { Elevated } & \text { Normal } \
\hline \text { DBI } & \text { Elevated } & \text { Nomal } \
\hline
\end{array}\) Based on this information, from what is George most likely suffering?

Accepted Answer

George's symptoms and lab results, including prolonged PT, APTT, elevated liver enzymes, and low activity of multiple clotting factors, suggest liver disease, which can cause impaired synthesis of clotting factors. The yellow ring around his eyes (Kayser-Fleischer rings) may indicate Wilson's disease, a type of liver disorder.

Question 12

What tests typically are utilized in the detection of lupus anticoagulants in the laboratory?

Accepted Answer

The answer of What tests typically are utilized in the...

Question 13

What type of VWD is the only type to have a decreased platelet count?

Accepted Answer

Type 2B VWD is the only type of VWD that is associated with a decreased platelet count. This is because type 2B VWD is caused by a gain-of-function mutation in the VWF protein, which leads to abnormal binding of platelets to VWF and increased platelet clearance. Both type 1 and type 2N VWD are characterized by normal platelet counts, while type 3 VWD is characterized by severe deficiency or absence of VWF and factor VIII, but not necessarily a decreased platelet count.

Question 14

Which assay would assess for the presence of a circulating nonspecific inhibitor?

Accepted Answer

The answer of Which assay would assess for the presence...

Question 15

Deficiencies of the fibrin-forming proteins often have a delayed bleeding symptom that is due to which of the following?

Accepted Answer

Fibrin is essential for the stabilization of the hemostatic plug. Therefore, the absence of fibrin leads to the inability to form a stable clot, leading to delayed bleeding. Excessive bleeding from a traumatic injury, bleeding from rupture of small arterioles, and formation of hematomas may occur in other bleeding disorders but are not specifically related to deficiencies of fibrin-forming proteins.

Quiz 31: Disorders of Secondary Hemostasis