Hemophagocytosis after bone marrow transplantation for JAK3-deficient severe combined immunodeficiency

Features of Hemophagocytic Lymphohistiocytosis in Infants With Severe Combined Immunodeficiency: Our Experience From Chandigarh, North India

Background

Hemophagocytic lymphohistiocytosis (HLH) is characterized by uncontrolled and excessive inflammation leading to high mortality. Aetiology of HLH can be primarily due to genetic causes or secondarily due to infections or rheumatological illness. However, rarely T-cell deficiencies like severe combined immunodeficiency (SCID) can develop HLH.

Objective

To describe clinical and laboratory features of SCID cases who developed HLH.

Methods

We collected clinical, laboratory, and molecular details of patients with SCID who developed HLH at our center at Chandigarh, North India.

Results

Of the 94 cases with SCID, 6 were noted to have developed HLH-like manifestations. Male-female ratio was 5:1. Median (inter-quartile range) age of onset of clinical symptoms was 4.25 months (2-5 months). Median (inter-quartile range) delay in diagnosis was 1 month (1-3.5 months). Family history of deaths was seen in 4 cases. Molecular defects in IL2RG were seen in 5 out of 6 cases. Documented infections include disseminated bacillus calmette-guerin (BCG) infection (n=2), blood stream infections (n=3) with Staphylococcal aureus (n=1), Klebsiella pneumonia (n=1), and Pseudomonas aeruginosa (n=1), pneumonia (influenza H1N1 strain, and K. pneumoniae (n=1).

Conclusion

Children with SCID can present with HLH-like manifestations secondary to fulminant infections. A high index of suspicion of SCID is needed in infants who present with HLH who have an associated infection or a suggestive family history. Occurrence of HLH-like manifestations in SCID suggests that T-lymphocytes may not have a significant role in immunopathogenesis of HLH.

Post-hematopoietic stem cell transplant hemophagocytic lymphohistiocytosis or an impostor: Case report and review of literature

HLH occurring after HSCT is a relatively rare disease. Many conditions may mimic or trigger HLH in post-HSCT period (eg, cytokine release syndrome, engraftment syndrome, graft rejection/failure, acute graft-vs-host disease, infections systemic inflammatory response syndrome/sepsis, and thrombotic microangiopathy). Moreover, this period is usually marked by febrile illness, cytopenia, and a "cytokine storm" leading to elevation of inflammatory biomarkers like ferritin and sCD25. These parameters overlap with the diagnostic criteria for HLH. Such confounding factors make the management of post-HSCT HLH quite challenging. We illustrate this critical issue with case report of a patient who was diagnosed with HLH after allogeneic HSCT for tAML. He received MP and CsA for HLH but VP-16 was not administered due to fear of severe myelosuppression. Fortunately, he responded well to treatment and remains in remission to date. We recommend caution while using HLH-94/HLH-2004 guidelines for the diagnosis and management of post-HSCT HLH. In this article, we pinpoint these issues with a brief review of all the pediatric cases and clinical studies of post-HSCT HLH along with a critical evaluation of its various diagnostic criteria. Finally, based on the limitations of current diagnostic criteria, we suggest a need for formulating disease-specific diagnostic criteria for post-HSCT HLH.

Chronic active Epstein-Barr virus infection as the initial symptom in a Janus kinase 3 deficiency child: Case report and literature review

RATIONALE

With the progress of sequencing technology, an increasing number of atypical primary immunodeficiency (PID) patients have been discovered, including Janus kinase 3 (JAK3) gene deficiency.

PATIENT CONCERNS

We report a patient who presented with chronic active Epstein-Barr virus (CAEBV) infection but responded poorly to treatment with ganciclovir.

DIAGNOSES

Next-generation sequencing (NGS) was performed, including all known PID genes, after which Sanger sequencing was performed to verify the results. Genetic analysis revealed that our patient had 2 novel compound heterozygous mutations of JAK3, a gene previously reported to cause a rare form of autosomal recessive severe combined immunodeficiency with recurrent infections. The p.H27Q mutation came from his father, while p. R222H from his mother. Thus, his diagnosis was corrected for JAK3-deficiency PID and CAEBV.

INTERVENTIONS

Maintenance treatment of subcutaneous injection of recombinant human interferon α-2a was given to our patient with 2 MU, 3 times a week.

OUTCOMES

Interferon alpha was applied and the EBV infection was gradually controlled and his symptoms ameliorated remarkably. Our patient is in good health now and did not have relapses.

LESSONS

The diagnoses of PID should be taken into consideration when CAEBV patients respond poorly to conventional treatments. Good results of our patient indicate that interferon α-2a may be an alternative treatment for those who are unwilling to accept hematopoietic stem cell transplantation (HSCT) like our patient. Literature review identified 59 additional cases of JAK3 deficiency with various infections.

Novel compound heterozygous mutations in a Japanese girl with Janus kinase 3 deficiency

Severe combined immunodeficiency (SCID) is the most severe form of primary immunodeficiency disease, and it is characterized by marked impairment in cellular and humoral immunity. Mutations in several genes cause SCID, one of which is Janus kinase 3 (JAK3), resulting in autosomal recessive T(-)B(+)NK(-) SCID. Only three patients with JAK3-deficient SCID have been reported in Japan. We herein describe the case of a 6-month-old girl with pneumocystis pneumonia, who was diagnosed with SCID with compound heterozygous JAK3 mutations (c.1568G>A + c.421-10G>A). One of the mutations was previously reported in another Japanese patient. The other mutation was a novel and de novo relatively deep intronic mutation causing aberrant RNA splicing. The patient was successfully treated with bone marrow transplantation from a haploidentical donor.

Hemophagocytic lymphohistiocytosis after hematopoietic stem cell transplantation in children: a nationwide survey in Japan

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is associated with hypercytokinemia in children. Although HLH can be also observed after hematopoietic stem cell transplantation (HSCT), the incidence and clinical features of HLH after HSCT remain obscure.

PROCEDURE

The clinical features of HLH after HSCT (post-HSCT HLH) were investigated in children with malignancies, immune deficiencies, or aplastic anemia. The HLH/Langerhans Cell Histiocytosis (LCH) Committee of the Japanese Society of Pediatric Hematology (JSPH) sent questionnaires to hospitals with JPSH members asking for details of cases in which HLH occurred after HSCT between 1998 and 2008.

RESULTS

Among 42 children who were diagnosed with post-HSCT HLH between 1998 and 2008 in Japan, 37 fulfilled our inclusion criteria; of these, 26 were classified as early-onset (onset <30 days after HSCT) and 11 were classified as late-onset (onset >30 days after HSCT). In the early-onset group, the presence of respiratory symptoms, high levels of total bilirubin, and triglycerides at onset and the lack of control of GVHD with tacrolimus were significantly associated with non-resolution of HLH (P < 0.05). The survival rate was significantly higher in patients with resolution of HLH than in those without resolution (59% vs. 14%, P < 0.05).

CONCLUSIONS

These findings suggest that early-onset post-HSCT HLH is a specific entity of HLH, and appropriate diagnosis and prompt management need to be established.