Hemophagocytic lymphohistiocytosis secondary to Epstein Barr virus and Leishmania co-infection in a toddler

Secondary hemophagocytic lymphohistiocytosis in children (Review)

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening condition characterized by hyperinflammation in an uncontrolled and ineffective immune response. Despite great improvement in diagnosis and treatment, it still represents a challenge in clinical management, with poor prognosis in the absence of an aggressive therapeutic approach. The present literature review focuses on secondary HLH at pediatric age, which represents a heterogeneous group in terms of etiology and therapeutic approach. It summarizes the most recent evidence on epidemiology, pathophysiology, diagnosis, treatment and prognosis, and provides a detailed description and comparison of the major subtypes of secondary HLH. Finally, it addresses the open questions with a focus on diagnosis and new treatment insights.

Hemophagocytic lymphohistiocytosis and visceral leishmaniasis in children: a series of cases and literature review

OBJECTIVE

Hemophagocytic lymphohistiocytosis syndrome (HLHS) is characterized by an immunological hyperactivation of cytotoxic T cells, natural killer cells, and macrophages, leading to the secretion of proinflammatory cytokines. HLHS associated with Visceral Leishmaniasis might be difficult to diagnose once symptoms are similar, resulting in the death of untreated patients. Our aim is to describe a series of cases of Visceral Leishmaniasis with HLHS admitted to a referral hospital for infectious diseases.

CASE DESCRIPTION

All 115 cases of Visceral Leishmaniasis referred to a referral center for pediatric infectious diseases were reviewed to identify the cases of HLHS. Five cases (4.5%) were confirmed with HLHS and they presented fever, splenomegaly, cytopenia, hypertriglyceridemia or hypofibrinogenemia, increased ferritin and hemophagocytosis in the bone marrow.

COMMENTS

It important to rule out HLHS in children with infectious diseases that do not respond adequately to treatment or in patients with severe symptoms, especially in leishmaniasis endemic areas.

A Brief Report and Mini-Review of Visceral Leishmaniasis-associated Hemophagocytic Lymphohistiocytosis in Children

We present the case of a 7-year-old boy who fulfilled the diagnostic criteria for hemophagocytic lymphohistiocytosis (HLH). Prompt visualization of his bone marrow confirmed the diagnosis of visceral leishmaniasis (VL). He responded well to treatment with liposomal amphotericin-B. The patient had a false-negative enzyme-linked immunosorbent assay for Leishmania infantum and a false-positive immunoglobulin M test for Epstein Barr virus (EBV). Because age at presentation is similar in children with VL and familial HLH for whom EBV is the usual trigger, ruling out VL is extremely important because nonspecific serologic tests for EBV can lead to the inappropriate diagnosis of EBV-driven primary HLH and to the administration of unnecessary immunochemotherapy.

Coinfection With Trypanosoma brucei Confers Protection Against Cutaneous Leishmaniasis

Infection with certain bacteria, parasites, and viruses alters the host immune system to Leishmania major influencing disease outcome. Here, we determined the outcome of a chronic infection with Trypanosoma brucei brucei on cutaneous leishmaniasis (CL) caused by L. major. C57BL/6 mice infected with T. b. brucei were given a sub-curative treatment with diminazene aceturate then coinfected with L. major by vector bites. Our results revealed that infection with T. b. brucei controls CL pathology. Compared to controls, coinfected mice showed a significant decrease in lesion size (P < 0.05) up to 6 weeks post-infection and a significant decrease in parasite burden (P < 0.0001) at 3 weeks post-infection. Protection against L. major resulted from a non-specific activation of T cells by trypanosomes. This induced a strong immune response characterized by IFN-γ production at the site of bites and systemically, creating a hostile inflammatory environment for L. major parasites and conferring protection from CL.

Complex Investigation of a Pediatric Haematological Case: Haemophagocytic Syndrome Associated with Visceral Leishmaniasis and Epstein⁻Barr (EBV) Co-Infection

BACKGROUND

Visceral leishmaniasis (VL) is an anthropozoonosis caused by an intracellular parasite belonging to the genus Leishmania. In the Mediterranean region, L. donovani and L. infantum are responsible for VL and dogs are the main reservoir. Haemophagocytic lymphohistiocytosis (HLH) represents a complication of VL and consists of unrestrained activation and proliferation of lymphocytes and macrophages, leading to uncontrolled immune activation. Haemophagocytic lymphohistiocytosis may also develop during viral infection, and Epstein⁻Barr virus (EBV) infection is one of the main HLH causes. Macrophage haemophagocytosis in the bone marrow aspirate is pathognomonic.

CASE PRESENTATION

The case involves a 19-month-old male infant presenting with a high persistent fever with a fluctuating pattern, pancytopaenia, hepatosplenomegaly, and a high triglyceride level. Initial investigations showed an EBV infection. Considering the persistent signs and symptoms, bone marrow aspiration was performed and confirmed the suspicion of HLH. In addition, the presence of Leishmania infection was shown. The patient was treated with liposomal amphotericin B and had complete resolution of his symptoms.

CONCLUSION

Diagnosis of VL represents a demanding challenge in endemic and non-endemic areas. Our case demonstrates that leishmaniasis should always be considered in the differential diagnosis in patients presenting with hepatosplenomegaly and cytopaenia with a persistent fever, even in cases of infectious mononucleosis. Moreover, the execution of bone marrow aspiration should not be delayed in order to diagnose and treat at an early stage the potential occurrence of VL, especially if complicated with HLH.

Leishmania Infantum and Epstein-Barr Virus Co-Infection in a Patient with Hemophagocytosis

The authors describe a rare case of a 27- year old previously healthy male presenting with high grade fever, pancytopenia, hepatosplenomegaly, high levels of ferritin and triglyceride, suggesting a diagnosis of hemophagocytic lymphohistiocytosis (HLH) syndrome. Other investigations showed a positive Leishmania infantum serology and high Epstein-Barr virus (EBV) viremia. The diagnosis of a visceral leishmaniasis was confirmed by bone morrow biopsy, which showed Leishman-Donovan bodies and evidence of HLH. The patient received liposomal amphotericin B and he had a complete resolution of his symptoms and clearance of EBV viremia. This case of HLH associated with visceral leishmaniasis and EBV co-infection raises the question about the significance of EBV in patients with HLH. The treatment of actual etiological agent can lead to complete cure while using current recommend chemotherapy for HLH-related EBV in a patient with hidden infection may have deleterious effects.

Hemophagocytic Syndrome in Children With Visceral Leishmaniasis

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a serious complication of visceral leishmaniasis (VL). The aim of this study is to describe demographical, clinical and laboratory features of HLH in children with VL.

METHODS

This is a retrospective cohort of children with HLH and VL admitted to a tertiary hospital in Northeast, Brazil, from January 2012 to April 2014. Clinical and laboratory data at admission and during hospital stay were reviewed. Acute kidney injury (AKI) was defined according to the pediatric Risk, Injury, Failure, Loss, End-stage kidney disease criteria.

RESULTS

A total 127 VL children were admitted, and 35 children had diagnosis of HLH. Mean age was 4.2 ± 4.3 years, with 62.9% males. Mean hospital stay was 29 ± 12 days. Main signs and symptoms were fever (100%), splenomegaly (94.2%) and hepatomegaly (60%). Laboratory findings showed pancytopenia, albumin 3.03 ± 0.77 g/dL, fibrinogen 236.1 ± 117.2 mg/dL, total calcium 8.2 ± 1.2 mEq/L, lactate dehydrogenase 1804 ± 1019 mg/dL, alkaline phosphatase 1275.4 ± 2160.5 IU/L, total bilirubin 1.9 ± 2.4 mg/dL, direct bilirubin 0.67 ± 1.02 mg/dL, indirect bilirubin 1.2 ± 2.2 mg/dL, aspartate aminotransferase 140.0 ± 145.3 IU/L, alanine aminotransferase 71.4 ± 81.1 IU/L, ferritin 4296.5 ± 8028.8 ng/dL and triglycerides 333 ± 141 mg/dL. AKI was observed in 16 children (45.7%), predominantly mild forms (93.75% "risk"). AKI group presented lower levels of platelets (69,131 ± 40,247 vs. 138,678 ± 127,494/mm, P = 0.035) than non-AKI. No patient required dialysis and there was no death.

CONCLUSIONS

HLH was not a rare complication of VL. Main symptoms were compatible with both VL and HLH. Main laboratory findings reflected HLH pathophysiology. Mild forms of AKI were a common complication of HLH. Despite the disease severity and complications, mortality was low.