PEDIATRÍA INTEGRAL Nº2 – MARZO 2024

M. Gómez de Pablos Romero*, M. Sánchez Martín**

*Adjunto de Pediatría de la Clínica Universidad de Navarra (Pamplona),
**Adjunto de Pediatría del Hospital Universitario La Paz

38. Resident-attending in the ED: Primary immune thrombocytopenia (ITP)

Attending/Father: Mónica Gómez de Pablos Romero. Adjunto de Pediatría de la Clínica Universidad de Navarra. Pamplona

Resident: María Sánchez Martín. Adjunto de Pediatría del Hospital Universitario La Paz. Madrid

Resident: Good afternoon Dr. Klein, I would like to talk to you about a patient I just saw.

Attending: Go on.

Resident: It’s a 3-year-old boy with a petechial rash since this morning. Yesterday he had a self-limited episode of epistaxis. His father says he had the flu two weeks ago, but now he doesn’t have any other symptoms and he appears well-being. However, the rash is quite striking. He doesn’t have any significant medical history.

Attending: Ok, so he doesn’t refer any systemic symptoms such as fever, anorexia, bone or joint pain, weight loss, GI (gastrointestinal) symptoms or headaches, and he doesn’t have a personal or family history of bleeding, right?

Resident: That’s it.

Attending: He hasn’t had any medications recently either?

Resident: No medications at all.

Attending: What about the rest of the physical examination? Any enlargement of lymph nodes, hepatomegaly or splenomegaly? Any other skin lesions?

Resident: The vital signs and the complete physical examination are normal except for the rash, consisting of petechiae and scattered purpura all over his legs.

Attending: So with all this information, what is your differential diagnosis?

Resident: Given the absence of systemic signs and symptoms, we could rule out malignancy, autoimmune disorder, infection or immune deficiency. I think the most likely diagnosis would be a primary immune thrombocytopenia. However, we should perform a blood test to confirm it.

Attending: Perfect, let me know when you have the results.

…

Resident: Excuse me Dr. Klein, the lab results for the boy I told you about before are back. He has 15,000 platelets/mcl without anemia or leukopenia and the differential WBC is normal. The red blood cell indices are also normal. The peripheral blood smear shows isolated thrombocytopenia, with normal-sized platelets, some activated lymphocytes but no blasts, and no schistocytes. There is no evidence of hemolysis or any other abnormal findings. He doesn’t have hematuria.

Attending: OK, so it seems he does have ITP. What would be the treatment according to the severity?

Resident: I would say it’s non-severe and doesn’t have a high bleeding risk, but he has had mucous involvement and his platelets are less than 20,000/mcl, so I would probably admit him to the hospital and start him on oral prednisone 4 mg/kg per day for 4 days followed by rapid tapering to avoid toxicities. We should also monitor the response to treatment.

Attending: I agree. Please inform his parents while I take care of the admission.

…

Resident: Hello. We have your son’s results back. It appears that he has what we call a primary immune thrombocytopenia. This is a condition of too few platelets, which are the blood cells that help blood to clot, hence the bruising and bleeding. It is the result of the immune system destroying his own platelets. The cause remains unclear in most cases but it can be triggered by a viral infection. We have to admit Tom to the hospital and start him on oral corticosteroid treatment because his platelet count is very low and this can lead to bleeding. Nonetheless, in mild cases like his, it is likely that it improves within a few days, making it possible for you to go home, and we should expect it to resolve completely in a few months.

Father: Can it happen again once he is recovered?

Resident: It could relapse, but the risk is low and there are other treatments that also show a good-response and could be used if needed.