Scenario 12: Immune Thrombocytopenia Purpura (ITP)

A 14-year-old female is brought to the Urgent Care by her mother who states that the girl has had an abnormal number of bruises and "funny looking red splotches" on her legs. These bruises were first noticed about 2 weeks ago and are not related to trauma. Past medical history not remarkable and she takes no medications. The mother does state the girl is recovering from a "bad case of mono" and was on bedrest at home for the past 3 weeks. The girl noticed that her gums were slightly bleeding when she brushed her teeth that morning.  

Labs at Urgent Care demonstrated normal hemoglobin and hematocrit with normal white blood cell (WBC) differential. Platelet count of 100,000/mm3 was the only abnormal finding. The staff also noticed that the venipuncture site oozed for a few minutes after pressure was released. The doctor at Urgent Care referred the patient and her mother to the ED for a complete work up of the low platelet count including a peripheral blood smear for suspected immune thrombocytopenia purpura (ITP). 

Question:

What is ITP and why do you think this patient has acute, rather than chronic, ITP? 

Answer:

Immune Thrombocytopenia purpura (ITP):

ITP is characterized by increased destruction of thrombocytes due to exaggerated immune response secondary to other conditions like infections, drug allergies, , auto-antibodies against thrombocytes. ITP can categorized as acute form or chronic form.

Acute or Chronic?

This client has acute form of ITP as evident from the past history that the client is recovering from "bad case of mono"nucleosis.

Acute form of ITP occurs secondary to viral infections such as Epstein Barr herpes virus in which the white blood cells like lymphocytes, monocytes and granulocytes are increased. As lymphocytes (B-lymphocytes and T lymphocytes) are involved in body's immune response, elevation of lymphocytes produces a hyper-immune response which destroys large of thrombocytes resulting in Immune Thrombocytopenia Purpura.

Chronic form of ITP occurs due to auto-antibody production and observed in elderly women between 20-40 years (acute form occurs in 10 to 35 years) and as the client in the given case are suffering symptoms from 2 weeks, which is of short duration, it can confirmed as acute form rather than chronic form.

Step-by-step explanation

Signs and Symptoms in the given case such as are indicative of Immune Thrombocytopenic purpura (ITP):

• Red splotches (Signs of petechiae and purpura)
• Bleeding gums
• Increased bleeding at the site of injection

Following points from the patient history reveals it is an acute presentation rather than chronic form:

• Recovering from bad form of mononucleosis
• Signs and symptoms are appearing from 2 weeks ago
• Denial of any other remarkable past history or medications

Acute Immune Thrombocytopenic purpura (ITP) mostly occurs in children and the symptoms subsides once the source of presentation is resolved (Epstein-barr herpes virus that causes Mononucleosis in this given client). As Acute ITP occurs secondary to other conditions (viral infection in this case), it is presented only for a short while and completely resolves within 1 to 2 months oncce the viral infection is reduced.

Treatment: As the condition is due to viral infection, it is self-limiting once the viral infection reduces. However, when the platelet count becomes less 50,000/ microliter (currently it is 100,000/ microliter) and severe bleeding occurs, treatment is initiated with Glucocorticoids to suppress immune reactions. Immunoglobulins, Romiplostim, Eltrombopag are administered to stimulate the thrombopoiesis (production of platelets)