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A board-style question with an explanation and a link to a relevant article is a recurring feature of TraineE-News. The goal of the case study is to clarify specific and timely teaching points in the field of hematology. The following case study focuses on a 9-year-old boy who presents to the clinic with a two-week history of thrombocytopenia. He had an episode of epistaxis three weeks prior and has been experiencing increased bruising over the last month. The patient’s past medical and surgical history is significant for obstructive sleep apnea and recurrent ear infections for which he had tonsillectomy and bilateral tympanostomy, respectively, with no excessive bleeding. There is no family history of bleeding disorders or thrombocytopenia. His laboratory results are as follows:

WBC 6500/μL (4000-11,000/μL)

Hemoglobin 14.5 g/dL (13.5-17.5 g/dL)

Platelets 44,000/μL (150,000-400,000/μL)

The patient’s physical examination and peripheral blood film are unremarkable with the exception of thrombocytopenia with large platelets.

At this time, what is the most appropriate treatment for this patient’s thrombocytopenia?

1. Anti-RhD immune globulin 25 mcg/kg/day for two days
2. Prednisone 2 mg/kg/day
3. Bone marrow aspiration and biopsy
4. Reassurance, recheck CBC in one month
5. Intravenous immunoglobulin 1g/kg for one dose

Answer

The most likely diagnosis in immune thrombocytopenia (ITP) in this otherwise healthy boy with isolated thrombocytopenia, otherwise unremarkable peripheral blood film, and negative family history. The typical presentation of ITP in childhood includes the sudden onset of bruising or petichiae in an otherwise well-appearing child between one and 10 years of age with isolated thrombocytopenia.

The majority of cases of ITP in childhood resolve spontaneously. Serious bleeding complications occur in approximately 3 percent of children with ITP. For children with no or mild bleeding, clinical observation is an appropriate therapeutic strategy regardless of the platelet count. Children should be advised to avoid activities which place them at high risk for bleeding (e.g., contact sports) until their platelet count normalizes. For children who are at higher risk of significant bleeding theraputic options include corticosterids, intravenous immune globulin (IVIG), and intravenous ant-Rho(D) immune globulin. When treatment is warrented, a single dose of IVIG (0.8 to 1 g/kg) or a short-course of corticosteroids are recommended first-line treatment options. Children who have a typical presentation of ITP do not require a bone marrow evaluation.

Editor's Note: This article has been revised to reflect that clinical observation in children is an appropriate therapeutic strategy regardless of platelet count, for those with no bleeding as well as those with mild bleeding. We apologize for the error in the answer section of this case study and for any confusion it may have caused.

References

1. Heitink-Pollé et al. . Blood. 2014 Nov 20;124(22):3295-307.
2. Neunert et al. . 2011 117: 4190-4207

Case study submitted by Alexandra Stevens, MD, Baylor College of Medicine, Houston, TX