# Platelet Satellitism in a Patient with Underlying Infection, Immune Thrombocytopenic Purpura (ITP) and Multiple Sclerosis

## TL;DR

A patient with infection, immune thrombocytopenic purpura, and multiple sclerosis showed platelet satellitism, a rare lab phenomenon that can falsely suggest low platelet count.

## Contribution

This case report highlights PS in a unique combination of coexisting medical conditions.

## Key findings

- Platelet satellitism was observed in a patient with infection, ITP, and multiple sclerosis.
- PS may be linked to IgG antibodies against platelet glycoprotein receptors.
- PS can cause falsely low platelet counts in lab tests but does not cause bleeding.

## Abstract

Platelet satellitism (PS) is an in vitro phenomenon of platelets adhering around white blood cells, especially in blood samples anticoagulated with K3EDTA. This, in some cases, can lead to spurious thrombocytopenia, without platelet dysfunction or bleeding events. Diagnosis is made by peripheral blood smear examination. The potential mechanism for PS remains largely unknown; however, it possibly involves the formation of IgG antibodies against the platelet glycoprotein receptor IIb/IIIa (GPIIb/IIIa). PS has been observed in various medical conditions, including infectious, autoimmune, and lymphoproliferative disorders, without an obvious causative relationship. Here, we describe a case of PS in a patient who presented with infection in the setting of underlying Immune Thombocytopenic Purpura and Multiple Sclerosis.