Haemophagocytic lymphohistiocytosis associated with fulminant hepatitis and multiorgan failure following primary Epstein-Barr virus and herpes simplex virus type 1 infection

Hemophagocytic Lymphohistiocytosis Triggered by Herpes Simplex Virus 1 and 2: A Narrative Review

Introduction: Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening syndrome characterized by an uncontrolled hyperinflammatory reaction. HLH is classified into primary (familial) and secondary (acquired). Secondary HLH is commonly triggered by infections, with viral infections being a leading cause. Its epidemiology and clinical features in cases associated with herpes simplex virus 1 and 2 remain underexplored. This study aimed to review all previously described cases of HSV-1 or -2-triggered HLH and provide information about this syndrome's epidemiology, microbiology, clinical characteristics, treatment, and outcomes. Methods: A narrative review was performed based on a search in PubMed, the Cochrane Library, and Scopus. Studies published until 27 April 2024 providing relevant data for HLH due to HSV 1 and 2 in humans were included. Results: We identified 29 eligible studies reporting HLH due to HSV 1 and 2, involving 34 patients. Half of them were adults, and half were neonates. Fever and splenomegaly were the most common clinical findings. Most patients were diagnosed with HSV-1 (64.7%), with PCR being the primary diagnostic method. The median duration of in-hospital treatment was 21 days, with acyclovir and steroids being the mainstays of therapy. The overall mortality rate was 41.2%, and AST levels emerged as an independent predictor of mortality. Conclusions: Our findings underscore the need for heightened awareness surrounding HLH triggered by HSV 1 and 2 and the importance of prompt diagnosis and tailored treatment approaches.

Hemophagocytic lymphohistiocytosis caused by herpes simplex virus type 1 in a young adult: a case report with literature review

Hemophagocytic lymphohistiocytosis is a severe hyperinflammatory syndrome that can be potentially life-threatening without appropriate treatment. Although viral infection is the most common trigger of hemophagocytic lymphohistiocytosis, cases of herpes simplex virus type 1-induced hemophagocytic lymphohistiocytosis are rare in adults. This study aims to provide a comprehensive overview of the clinical characteristics and treatment outcomes associated with HSV-1-induced HLH. We herein report an adult case of hemophagocytic lymphohistiocytosis caused by herpes simplex virus type 1, diagnosed on the basis of peripheral blood metagenomic next-generation sequencing results. The patient exhibited a favorable response to treatment, involving dexamethasone, intravenous immunoglobulin, and acyclovir. Notably, etoposide administration was deemed unnecessary, and there has been no recurrence of the disease within the year following treatment. Early and sensitive recognition, rapid and precise diagnosis, and timely and appropriate treatment facilitated the successful treatment of this case.

Hepatitis E virus-associated haemophagocytic lymphohistiocytosis

We report the first documented case of hepatitis E virus-associated haemophagocytic lymphohistiocytosis. This case emphasizes the fact that infectious agents other than those classically described should be taken into consideration as a potential trigger of virus-associated haemophagocytic syndrome. Prompt recognition is crucial to start early treatment of the underlying infection and possibly improve the outcome of this frequently fatal syndrome.

Postpartum disseminated HSV-1 infection with hemophagocytic lymphohistiocytosis and fulminant neonatal herpes infection

The present study describes a 19-year-old woman with systemic herpes simplex virus (HSV)-1 infection postpartum, and a fatal course of neonatal herpesvirus infection. The mother experienced an unusual disease course with hemophagocytic lymphohistiocytosis (HLH) and persistence of HSV-1 DNA for 15 weeks. Functional investigation of cells from the mother demonstrated significantly impaired induction of antiviral interferons and cytokines in response to viruses and various ligands in the context of normal activation of the transcription factors NF-κB and IRF3. Whole exome sequencing did not reveal any functionally validated genetic variants. We suggest that the functionally impaired antiviral responses, potentially caused by a mutation in CASP8 or other variants in non-coding regions of the genome, contributed to the unusually severe disease course in two generations with disseminated HSV-1 infection evolving into HLH in the mother, and a fatal neonatal HSV-1 infection.

Disseminated Herpes Simplex Masquerading as Hemophagocytic Lymphohistiocytosis: A Case Report

INTRODUCTION

Marked elevation in serum ferritin levels may be seen in disseminated infection or severe organ failure states, but it is also present in hemophagocytic lymphohistiocytosis (HLH). Herpes simplex virus (HSV) hepatitis has a high mortality rate, even in immunocompetent individuals, in whom it is rarely reported. We present a case of hyperferritinemia with features initially suggestive of a diagnosis of HLH but that ultimately proved to be fulminant HSV hepatitis.

CASE PRESENTATION

A 56-year-old man with an indolent undiagnosed brain mass presented with progressive neurologic deficits and was found to have fevers, cytopenias, transaminitis, and hyperferritinemia. Initially, HLH was suspected; however, the ultimate diagnosis was HSV hepatitis with dissemination. Although the patient was treated with intravenous acyclovir, multiorgan failure developed, and he died.

DISCUSSION

This case highlights the importance of considering alternative causes for a rise in ferritin levels when HLH is on the differential. Additionally, we discuss the diagnostic and therapeutic implications of HSV hepatitis, and we review the literature for cases presenting in immunocompetent hosts.

V348I mutation in UL23 gene of human herpesvirus 1 in a case of herpetic hepatitis and haemophagocytic lymphohistiocytosis

We herein report the case of a young immunocompetent adult patient with a rapidly fatal haemophagocytic lymphohistiocytosis syndrome related to human herpesvirus 1 (HHV-1) infection, with herpetic hepatitis and persistent high-level viraemia despite treatment with acyclovir. Haemophagocytic lymphohistiocytosis was confirmed in the patient's spleen and bone marrow. HHV-1 DNA was extracted from whole blood and liver biopsy and the UL23 gene was sequenced. A V348I natural polymorphism of the TK protein was found in blood and liver specimens. Further studies are needed to investigate the role of this polymorphism in the development of systemic immune dysregulation.