# A Case of Severe Refractory Immune Thrombocytopenia Exacerbated by Respiratory Syncytial Virus Infection

## TL;DR

A healthy adult developed severe, treatment-resistant immune thrombocytopenia possibly worsened by a respiratory syncytial virus infection.

## Contribution

This is a rare case report of severe ITP exacerbated by RSV in an otherwise healthy adult.

## Key findings

- The patient's thrombocytopenia was refractory to standard treatments like IV immunoglobulin and steroids.
- Platelet counts normalized only after cyclosporine treatment.
- RSV infection may have played a role in exacerbating the ITP.

## Abstract

Immune thrombocytopenia (ITP) is an immunological phenomenon in which antibodies target platelet surface proteins, resulting in platelet destruction, as well as platelet opsonization and clearance by splenic and hepatic macrophages. Antibodies and cytotoxic T cells may also directly target megakaryocytes in the bone marrow, thereby compromising platelet production and further lowering platelet counts. This disease is largely idiopathic but may also result secondary to autoimmune disorders, malignancies, medication side effects, and recent infections. Currently, the understanding of infections and thrombocytopenia is poorly understood. There are no current well-described reports of severe ITP exacerbations due to respiratory syncytial virus (RSV) infection, especially in a relatively healthy adult with no significant hematologic or oncologic history. This case report describes a 57-year-old woman with no significant past medical history who presented to the ED with a three-day duration of epistaxis in the setting of upper respiratory tract infection symptoms, as well as easy bruising over the past several months. Initial bloodwork in the ED revealed severe thrombocytopenia and anemia. Treatment was initiated, starting with platelet and packed red blood cell infusion. Her anemia resolved, but her thrombocytopenia persisted and remained largely refractory to multiple first-line treatments, including intravenous immunoglobulin therapy, steroids, and thrombopoietin receptor agonists. It was only after a four-day treatment with cyclosporine that her platelet count was normalized. This case report describes an unusual presentation of severe, refractory ITP that may have been exacerbated by an RSV infection.