X-Linked Lymphoproliferative Disease Type 2 With Activation of Hemophagocytic Lymphohistiocytosis Secondary to Epstein-Barr Virus Infection

Abstract

Hemophagocytic lymphohistiocytosis (HLH) is a rare yet potentially life-threatening syndrome. It is best described as uncontrolled immune system activation leading to hemophagocytosis. Our case report aims to present a practical approach, discuss the challenges in the diagnosis and management of HLH, and to shed light on the X-linked lymphoproliferative disease type 2 (XLP-2) gene, STXBP2 gene (as a carrier), and Epstein-Barr virus (EBV) infection in relation to HLH. This is a 2-year-8-month-old Saudi boy, who presented to the emergency department with fever for more than 7 days, not associated with any other major complaints. During the first couple of days of admission, primary results showed hyperferritinemia, low fibrinogen, anemia, high inflammatory markers, high D-dimer, and increasing liver enzymes and triglycerides. The patient fulfilled the diagnostic criteria of HLH on the third day of admission. Further investigations revealed a genetic mutation in XLP-2 gene, STXBP2 gene (as a carrier) and EBV infection causing HLH. HLH-94 protocol was used for management. The patient had an excellent clinical outcome, unexpectedly, by only using dexamethasone, with complete remission and no recurrence up to date. HLH is not frequently encountered in daily practice. However, it can be fatal. This case report describes a unique case of XLP-2, STXBP2 carrier with extreme EBV infection and activation of HLH, who was successfully brought into remission by partial application of HLH-94 protocol and careful clinical and laboratory monitoring. The diagnosis and management of HLH can be challenging. However, a reasonable clinical judgment can improve the outcomes.