A 33-year-old woman is evaluated ofspontaneous gum bleeding 2 weeks. She has also had purplish skin lesions over her legs for 2 months. Last week, she had one episode of hematuria and watery diarrhea, both of which resolved without treatment. She has mild asthma. Her brother has hemophilia. Her only medication is a fenoterol inhaler. She appears healthy. Her temperature is 37.1°C , pulse is 88/min, respirations are 14/min, and blood pressure is 122/74 mm Hg. The abdomen is soft and nontender; there is no organomegaly. extremities. Laboratory studies show:

Hemoglobin: 13.3 mg/dL

MCV: 94 μm3

Leukocyte count 8,800/mm3

Platelet count: 18,000/mm3

Bleeding time: 9 minutes (N = 2–7)

Normal PT and PTT

Which of the following is the most likely underlying mechanism of this patient's symptoms?

A 32-year-old woman is complaining of a 12 month history of intermittently heavy periods and nosebleeds up to 6-8 times a week for 2 months, as well as frequent atraumatic bruising. She has had no weight loss or fevers, and denies any abdominal pain or arthralgia.

She has no significant medical or drug history, and takes no regular medications nor any herbal remedies.

On examination, she has a multiple purpura on her sacrum, which extend down to the buttocks.

Blood tests reveal:

Hb124 g/L Female: (115 - 160)

Platelets18*109/L(150 - 400)

WBC7*109/L(4.0 - 11.0)

Prothrombin time (PT)12 secs(10-14 secs)

APTT: 28 Sec(25-35 secs)

What is the most likely diagnosis?

What is the most common inherited bleeding disorder?

A 16-year-old girl is evaluated for recurrent episodes of nose bleeding for several months. The episodes occur unexpectedly and stop after a few minutes by elevating the upper body and bending the head forward. Menses occur at regular 27-day intervals with heavy flow. Her last menstrual period was 3 weeks ago. Vital signs are within normal limits. Physical examination shows no abnormalities. Laboratory studies show:

Hemoglobin: 11 g/dL

Hematocrit: 34%

Leukocyte count: 7,000/mm3

Platelet count: 180,000/mm3

Prothrombin time: 13 sec

Partial thromboplastin time: 45 sec

Fibrin split products: negative

The bleeding time is 10 minutes (N = 2–7).

Which of the following is the most appropriate next step in treatment?

Tranexamic acid

What is the mechanism of action of DDAVP in von Willebrand's disease?

A 3-year-old boy is brought to the emergency department because of pain and swelling of his right knee joint for 1 day. He has not had any trauma to the knee. He was born at term and has been healthy since. His maternal uncle has a history of a bleeding disorder. His temperature is 37.1°C (98.8°F) and pulse is 97/min. The right knee is erythematous, swollen, and tender; range of motion is limited. No other joints are affected. An x-ray of the knee shows an effusion but no structural abnormalities of the joint. Arthrocentesis is done. The synovial fluid is bloody. Further evaluation of this patient is most likely to show which of the following?

An 8-year-old boy is brought to the physician for evaluation of an excessive bleeding after undergoing a dental procedure. Laboratory studies show a platelet count of 195,000/mm³, a partial thromboplastin time of 44 sec, and a prothrombin time of 12 sec. A one-stage clotting assay shows a decreased factor VIII. Therapy with a drug that acts on endothelial cells is initiated. This drug is most likely to result in which of the following?

A previously healthy, 16-year-old boy is brought to the emergency department with persistent bleeding from his gums after an elective removal of an impacted tooth. Multiple gauze packs were applied with minimal effect. He has a history of easy bruising. His family history is unremarkable except for a maternal uncle who had a history of easy bruising and joint swelling. Laboratory studies show:

Hematocrit 36%

Platelet count 170,000/mm3

Prothrombin time 13 sec

Partial thromboplastin time 65 sec

Bleeding time 5 min (N = 2–7)

Peripheral blood smear shows normal-sized platelets. Which of the following is the most likely diagnosis?

A 34-year-old man who is known to have type 1 von Willebrand's disease asks for advice. He is due to have a tooth extracted at the dentist next week. Which one of the following is the most appropriate management to reduce the risk of bleeding?

A 4-year-old boy is admitted after developing a haemarthrosis in his right knee whilst playing in the garden. The following blood results are obtained:

Platelets220 * 109/l PT11 secsAPTT76 secs Factor VIIIc activityNormal

What is the most likely diagnosis?