Hemophagocytic Lymphohistiocytosis In Children Research Articles

Successful treatment of diffuse alveolar hemorrhage secondary to Mycoplasma pneumoniae complicated with hemophagocytic lymphohistiocytosis in children: a case report and non-systematic literature review

BackgroundAfter quarantine-related measures were completely lifted in China, the respiratory infection rate of children caused by Mycoplasma pneumoniae (MP) increased significantly, and MP infection may lead to rare severe intra- and extrapulmonary manifestation. Hemophagocytic lymphohistiocytosis (HLH) and diffuse alveolar hemorrhage (DAH) are life-threatening clinical syndromes. Timely recognition may contribute to timely treatment and an improved prognosis. Currently there are no reports of children with DAH secondary to MP infection complicated with HLH.Case presentationWe successfully treated a previously healthy school-aged child who was admitted to the pediatric intensive care unit with fever, cough, drowsiness, and progressive dyspnea. HLH was confirmed by clinical and testing criteria, DAH was indicated by computed tomography scan of the chest, and Mycoplasma antibody detection and endotracheal aspirates pathogen metagenomic next-generation sequencing (mNGS) confirmed MP infection. After invasive mechanical ventilation, antibiotics, and glucocorticoid treatment, the patient recovered well and was discharged. At follow-up, she did not experience any more initial symptoms. For the fourth consecutive month, all indexes remained normal.ConclusionmNGS can be considered for identifying the causative agent of infection in patients with DAH and/or HLH. The clinical manifestations of DAH in children may only present as acute hypoxic respiratory failure, significantly decreased hemoglobin without bleeding elsewhere, and chest imaging findings may assist in the diagnosis of DAH. When MP infection is associated with hemocytopenia, HLH should be considered.

Successful treatment of diffuse alveolar hemorrhage secondary to Mycoplasma pneumoniae complicated with hemophagocytic lymphohistiocytosis in children: a case report and non-systematic literature review

Successful treatment of diffuse alveolar hemorrhage secondary to Mycoplasma pneumoniae complicated with hemophagocytic lymphohistiocytosis in children: a case report and non-systematic literature review

Outcome and Prognostic Factors of Hemophagocytic Lymphohistiocytosis in Children: Experience From a Low- and Middle-Income Country.

Objective Hemophagocyticlymphohistiocytosis (HLH) is a life-threatening condition especially in low- and middle-income countries (LMICs). This study was done to evaluate the outcome and prognostic factors of HLH in patients presenting to our center. Methods The study was carried out at the Paediatric Oncology Department of Combined Military Hospital (CMH) in Rawalpindi, Pakistan. All cases of HLH, from one month to 15 years of age enrolled between January 1, 2013 to June 30, 2023, were included. IBM SPSS Statistics for Windows, version 25.0 (released 2017, IBM Corp., Armonk, NY) was used for statistical analysis, and t-test and chi-square tests were used for comparison between continuous and categorical variables. Frequencies and percentages were calculated for categorical variables. Results Out of 115 patients, seven (6%) abandoned the treatment. The data of 108 cases, including 58 males (53.7%), were analyzed. The mean age at diagnosis was 31.5 ± 39.03 months. The mean time to reach a pediatric oncologist was 30.20 ± 22.15 days. Fever and pallor were common symptoms occurring in 107 (99.1%) and 98 (90.7%) cases, respectively. Jaundice was present in 44 (40.7%), visceromegaly in 64 (59.3%), and bruising/bleeding in 16 cases (14.8%). Twenty-six (24.1%) patients underwent hematopoietic stem cell transplant (HSCT), out of which 17 (65.4%) children were cured. Overall survival at two years, five years, and 10 years was 38%, 37%, and 36.1%, respectively. Disease-free survival at two years, five years, and 10 years was 33.3%, 32.4%, and 31.5%, respectively. Conclusion HLH leads to high mortality due to delayed or misdiagnosis in LMICs. Early diagnosis and early referral to a pediatric oncologist is the detrimental factor in survival for HLH. HSCT is the treatment of choice for primary, refractory, or relapse cases.

HEMOPHAGOCYTIC LYMPHOHISTIOCYTOSIS IN PEDIATRIC PRACTICE

The article presents a review of literature sources highlighting the issues of clinical and laboratory diagnosis of hemophagocytic lymphohistiocytosis in children. The authors of various observations have repeatedly emphasized hemophagocytic lymphohistiocytosis continues to be a life-threatening disease despite modern implementations in diagnosis and treatment. At the same time, the prognosis and outcome are largely determined by the timeliness of diagnosis and the right tactic. The review is illustrated by a clinical example of a fatally ended case of an infant, he was diagnosed posthumously based on the results of a molecular genetic tests.

Genetic and clinical characteristics of primary hemophagocytic lymphohistiocytosis in children.

To analyze the genetic variation and prognosis of primary hemophagocytic lymphohistiocytosis (pHLH) in children and the clinical features of isolated central nervous system HLH (CNS-HLH). We retrospectively analyzed the clinical and genetic data of 480 HLH children admitted to our hospital from September 2017 to September 2022. There were 66 patients (13.75%) with pHLH, and the median age was 3.21years (0.17-12.92years). Variants in UNC13D (22/66, 33.33%), PRF1 (20/66, 30.30%) and XIAP (11/66, 16.67%) were the most common. More CNS involvement was observed in pHLH patients than in secondary hemophagocytic lymphohistiocytosis (sHLH) patients (50% vs. 25.3%, P = 0.001). Eight pHLH patients had isolated CNS-HLH at onset, which progressed to systemic HLH within 10-30days to several years. Among them, five patients who underwent hematopoietic stem cell transplantation (HSCT) survived without CNS sequelae, and the three patients who did not undergo HSCT died of disease progression or recurrence. Determination of natural killer (NK) cell cytotoxicity and CD107a levels had low sensitivity and specificity in the diagnosis of pHLH, especially in patients with PRF1 and XIAP mutations. The 3-year overall survival (OS) was significantly lower in pHLH patients than in sHLH patients (74.5% ± 14.7% vs. 89.2% ± 3.53%, P = 0.021) and in patients with CNS involvement than in those without (53.8% ± 26.07% vs. 94.4% ± 10.58%, P = 0.012). There was a significant difference in OS among pHLH patients with different gene variants (P = 0.032); patients with PRF1 variants had poor 3-year OS, and patients with XIAP variants had good 3-year OS (50% ± 28.22% and 100%, respectively). pHLH patients with distinct variants have different prognoses. Isolated CNS-HLH patients are easily misdiagnosed, and HSCT may be beneficial for these patients. Determination of NK cell cytotoxicity and CD107a levels cannot precisely distinguish pHLH from sHLH.

The Dosage Recommendation of Cyclosporin in Children with Hemophagocytic Lymphohistiocytosis based on Population Pharmacokinetic Model.

Cyclosporin is one of the therapeutic regimens for hemophagocytic lymphohistiocytosis (HLH); however, the optimal dosage of cyclosporine in children with HLH is unknown. It has been found that piperacillin-tazobactam affects the cyclosporine pharmacokinetic process in pediatric HLH patients. Thus, the purpose of the present study was to recommend cyclosporin dosage for pediatric HLH with and without piperacillin- tazobactam. A previously established cyclosporine population pharmacokinetic model for pediatric HLH patients has been used in this study to recommend optimal dosage based on Monte Carlo simulation. The pediatric HLH patients have been included in eight weight groups (5, 10, 20, 30, 40, 50, 60, 70 kg) for sixteen dosages (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 mg/kg), split into one dose or two doses. The optimal cyclosporin dosages for children having HLH without piperacillin-tazobactam have been found to be 15, 13, 12, 11, 10, and 9 mg/kg, split into two doses for weights of 5-7, 7-10, 10-20, 20-28, 28-45, and 45-70 kg, respectively. For children with HLH, optimal cyclosporin dosages with piperacillin-tazobactam have been found to be 8 and 7 mg/kg, split into two doses for weights of 5-20 and 20-70 kg, respectively. It is the first time that the cyclosporin dosage regimens for HLH in children have been developed based on Monte Carlo simulation, and the initial dosage optimizations of cyclosporine in pediatric HLH patients have been recommended.

Sintilimab treatment for chronic active Epstein–Barr virus infection and Epstein–Barr virus-associated hemophagocytic lymphohistiocytosis in children

BackgroundChronic active Epstein–Barr virus infection (CAEBV) and Epstein–Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) are rare but life-threatening progressive diseases triggered by EBV infection. Glucocorticoid/immunosuppressants treatment is temporarily effective; however, most patients relapse and/or progress. Hematopoietic stem cell transplantation (HSCT) is a potentially curative therapy; however, there are risks of transplantation-associated complications. Currently there is no standard treatment for CAEBV and EBV-HLH. Programmed death protein 1 (PD-1) inhibitors have achieved a high response in many EBV-related diseases. Sintilimab (a recombinant human IgG4 monoclonal antibody against PD-1) disrupts the interaction between PD-1 and its ligand, leading to T cell reinvigoration.MethodsA retrospective analysis was performed on three children with CAEBV or EBV-HLH in the Children’s Hospital of Soochow University between 12 December 2020 and 28 November 2022. The efficacy of sintilimab was evaluated.ResultsThree patients, including two males and one female, were analyzed. Among them, two children were diagnosed with CAEBV with intermittent fever for more than four years, and one child was diagnosed with EBV-HLH. After sintilimab treatment and a mean follow-up of 17.1 months (range 10.0–23.3 months), patients 1 and 3 achieved a complete clinical response and patient 2 achieved a partial clinical response. All three children showed a > 50% decrease in EBV-DNA load in both blood and plasma. EBV-DNA copies in sorted T, B, and NK cells were also markedly decreased after sintilimab treatment.ConclusionOur data supported the efficacy of PD-1 targeted therapy in certain patients with CAEBV and EBV-HLH, and suggested that sintilimab could provide a cure for these diseases, without HSCT. More prospective studies and longer follow-up are needed to confirm these conclusions.

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.

Clinical and Laboratory Characteristics of Hemophagocytic Lymphohistiocytosis in Children With Severe Dengue During the 2019-2020 Outbreak in Southern Colombia.

Hemophagocytic lymphohistiocytosis (HLH) is characterized by uncontrolled activation of inflammatory cells and an exaggerated release of cytokines. It can be triggered by different factors, including viruses, such as dengue. The objective of this study was to characterize the clinical and laboratory profiles of children with severe dengue and HLH, and to identify the risk factors for this clinical complication. An analytical study was conducted in children with severe dengue who were treated in an intensive care unit between January 2019 and March 2020. Clinical and laboratory factors were compared between patients with and without HLH. HLH represented 13.4% (15/112) of children with severe dengue. Patients with HLH had a long-lasting fever (10.1 vs. 5.8 days; P = 0.012), low hemoglobin levels (7.6 vs. 10.8 g/dL; P = 0.000) and high aspartate aminotransferase values (4443 vs. 1061 U/L; P = 0.002), alanine transaminase (1433 vs. 487 U/L; P = 0.004), partial thromboplastin time (80.6 vs. 51.8 seconds; P = 0.010), prothrombin time (23.5 vs. 19.6 seconds; P = 0.024), triglycerides (333.7 vs. 223.2 mg/dL; P = 0.005), lactate dehydrogenase (4209 vs. 1947 U/L; P = 0.006), soluble CD25 (3488 vs. 1026 pg/mL; P = 0.014), and presented with higher frequency of myocarditis (66.7% vs. 38.3%; P = 0.048), hepatitis (5.3% vs. 1.3%; P = 0.014), bacterial coinfection (73.3% vs. 26.7%; P = 0.010) and fatal outcome (26% vs. 5%; P = 0.037). HLH is a serious life-threatening clinical complication of dengue virus infection that must be considered, particularly during outbreaks.

Secondary hemophagocytic lymphohistiocytosis in children with dengue: A case series

Secondary hemophagocytic lymphohistiocytosis in children with dengue: A case series

Paediatric haemophagocytic lymphohistiocytosis: clinical presentation and outcome of 20 patients at a single institution.

Paediatric haemophagocytic lymphohistiocytosis (pHLH) is a potentially life-threatening condition with significant diagnostic and therapeutic difficulties. The purpose of this study was to describe the clinical presentation, the diagnostic challenges, and the outcomes of haemophagocytic lymphohistiocytosis (HLH) in children assessed at Mukalla Hospital, Yemen. Data from 20 medical records of HLH patients admitted between January 2010 and May 2022 were retrospectively analysed. The median age at presentation was 3.5 ± 5.1 years. Male: female ratio was 1:1. The median time for referral to the hospital was 30 ± 64 days. The most common clinical manifestations were fever and pallor in 95% of cases, and splenomegaly (85%). Hepatomegaly, chest, renal and neurological manifestations were detected in 80%, 45%, 15% and 20% of cases, respectively. Bone marrow haemophagocytosis was detected in 60% of cases. Sixteen patients fulfilled the HLH diagnostic criteria, and 11 patients (55%) received the HLH 2004 protocol. Out of the 20 patients, three (15%) patients are alive. Fourteen patients died, with overall mortality of 82.35%. All mortalities were due to HLH disease with multi-organ failure. Relapse was noticed in five patients either during treatment or after full recovery. pHLH is a challenging emergency with a high mortality rate. High clinical suspicion is essential for early detection and intervention to improve the prognosis.

18F-FDG PET/CT for Identifying the Potential Primary Diseases and Predicting Prognosis of Secondary Hemophagocytic Lymphohistiocytosis in Children.

Hemophagocytic lymphohistiocytosis (HLH) is a rare, potentially fatal illness, which can be divided into primary HLH (pHLH) and secondary HLH (sHLH). pHLH can be driven by genetic defections. Moreover, the sHLH is usually be triggered by malignancy or non-malignancy diseases. Sixty-two newly diagnosed sHLH patients with known etiology and those who underwent 18F-FDG PET/CT examination from July 2018 to December 2020 were retrospectively analyzed. They were divided into malignancy-associated HLH (M-HLH, n = 13) and non-malignancy-associated HLH (NM-HLH, n = 49). The metabolic parameters of the liver (Li), spleen (Sp), bone marrow (BM), lymph nodes (LN), and their ratios to the liver background (LiBG) and mediastinum (M) were compared between two groups. These metabolic parameters were evaluated for correlation with laboratory parameters and prognostic parameters. We found that the SUVmax-LN/Sp/Li and SUVmean-Sp in M-HLH were significantly higher than those in NM-HLH (P=0.031, 0.035, 0.016, and 0.032). The malignant disease should be considered when SUVmax-LN was higher than 4.41 (sensitivity 61.5%, specificity 81.6%). Hypermetabolic lesions in extranodal organs were more likely to occur in M-HLH than in NM-HLH (P=0.011). IFN- γ was positively correlated with SUVmax-BM/Li/Sp and SUVmean-BM/Li/Sp (P < 0.05). Ferritin, sCD25, IL-6, and IL-10 were positively correlated with SUVmax-Sp and SUVmean-Sp (P < 0.05). In Epstein–Barr virus-associated HLH (EBV-HLH), the SUV parameters of bone marrow were significantly correlated with a poor 2-week treatment response, overall survival, and event-free survival (P < 0.05). We conclude that some 18F-FDG PET/CT metabolic parameters can help identify the etiology of sHLH in children and provide directions for further inspection. The malignant disease should be considered when the SUVmax-LN is higher than 4.41 and hypermetabolic lesions occur in extranodal organs. In EBV-HLH, a higher SUV of bone marrow is associated with a poorer prognosis.

Clinical and molecular characteristics of Streptococcus pneumoniae-associated hemophagocytic lymphohistiocytosis in children

Objective: To summarize the clinical features of Streptococcus pneumoniae-associated hemophagocytic syndrome (SP-HLH), and the serotypes and drug-resistant characteristics of the isolated strains. Methods: There were 15 children with SP-HLH admitted to the Pediatric Intensive Care Unit (PICU) of Beijing Children's Hospital, Capital Medical University from January 2013 to December 2020 were included in this study. Clinical data including children's general characteristics, clinical features, laboratory examinations, treatments, prognosis and the outcomes of follow-up by May 2021 were analyzed retrospectively. The serotypes and drug resistance of the isolated strains were identified. All children were divided into the clinical improvement group and the death group. Mann-Whitney U test, Fisher's exact test were used to compare the data of the two groups. Results: Among the 15 children with SP-HLH, 8 were males and 7 were females. The age of these children was 1.0 (1.0, 2.5) years. Regarding the primary infection, there were 9 cases of severe pneumonia, 3 cases of meningitis and 3 cases of blood stream infection. None of these children had received pneumoniae conjugate vaccine (PCV) and all of them were admitted to the PICU. Respiratory failure was observed in 10 patients, acute renal injury in 5, and hemolytic uremic syndrome in 3 patients. All children received glucocorticoids and high-dose intravenous immunogloblin (IVIG) in addition to anti-infective treatment. Eight of the children were cured while the other 7 died. The neutrophil count in the death group was lower than that in the clinical improvement group ((5.0 (1.7, 9.3) × 109 vs. 5.2 (3.4, 10.5) ×109/L, Z =-2.43, P<0.015), and the length of hospital stay and days of PICU stay in the death group were both shorter than those in the improvement group statistically (3 (1, 11) vs. 39 (34, 48) d, 2 (1, 4) vs. 19 (12, 31) d, Z=-3.25, -3.24, both P=0.001). Ten serotypes of Streptococcus pneumoniae were identified, including 4 strains of 19F, 3 of 19A, 1 of 23F, 1 of 15A and 1 of 14, among which 9 strains (9/10) were covered by PCV13. All strains were resistant to erythromycin yet sensitive to vancomycin and linezolid. Conclusions: SP-HLH is more common in children under the age of 3, with a high mortality rate. The death cases have lower neutrophil count and rapid disease progression. The comprehensive treatment is anti-infective combined with glucocorticoids and high-dose IVIG. The predominant serotypes are 19F and 19A and all isolated strains were susceptible to vancomycin and linezolid.

Lymphoma-based therapy for refractory or relapsed Epstein–Barr virus–related hemophagocytic lymphohistiocytosis in children

Epstein-Barr virus-related hemophagocytic lymphohistiocytosis (EBV-HLH) is a life-threatening hyperinflammatory syndrome. Although etoposide-based immunochemotherapy has improved survival rates, consensus regarding the appropriate salvage therapy for patients with refractory or relapsed EBV-HLH is lacking. We performed a retrospective study to examine the efficacy of a lymphoma-based treatment regimen for children with refractory or relapsed EBV-HLH. The data of six children were analyzed. Four had cytogenetic abnormalities, and two experienced a transition to EBV-positive T-cell lymphoma. They were treated with an intensive chemotherapy regimen modified from that used in the Berlin-Frankfurt-Münster Group Trial as salvage therapy. Five patients (83%) achieved complete response. Four patients (67%) were disease free for a median of 10 years without undergoing allogeneic hematopoietic stem cell transplantation. No grade 3 or 4 nonhematologic adverse events occurred. Lymphoma-based chemotherapy is a potential curative treatment for some subgroups of children with refractory or relapsed EBV-HLH.

Soluble Interleukin-2 Receptor Level as a Marker of Hemophagocytic Lymphohistiocytosis in Children With Severe Dengue.

Dengue induced-hemophagocytic lymphohistiocytosis (HLH) is increasingly recognized as an important cause of secondary HLH. Early identification of dengue HLH and directed therapy for HLH may help to alter the outcomes in critically ill patients. Soluble interleukin-2 receptor (IL2R) is a useful inflammatory marker and is seen to correlate with HLH disease activity. There is scarcity of data on IL2R in pediatric dengue patients with HLH. All patients (age < 18 years) with severe dengue confirmed by positive dengue IgM ELISA admitted to PICU were retrospectively enrolled. Patientswere screened for presence of HLH according to HLH 2004 criteria. Hemogram, ferritin, fibrinogen, liver, and renal function tests were noted. Patients who met four or more HLH criteria were treated with steroids and IL2R levels were sent to confirm the diagnosis of HLH. Out of 15 patients, nine patients met the criteria of HLH. IL2R levels were high in all HLH patients (mean 51,711, range 18,000–98,715 pg/mL). Mean ferritin levels were high in the HLH group as compared to non-HLH group (mean ferritin 34,593 vs. 3,206 ng/mL; p-value 0.004). Liver dysfunction was notably higher in the HLH group compared to non-HLH group (mean alanine aminotransferase 6,621 U/L vs. 165.6 U/L; p-value 0.04, mean aspartate aminotransferase 2,145 U/L vs. 104.2 U/L; 0.04, bilirubin level 4.2 mg/dL vs. 0.7 mg/dL; p-value 0.03). Four patients in the HLH group had acute kidney injury (AKI) and two required renal replacement therapy in the form of sustained low efficiency dialysis (SLED). Requirement for invasive ventilation was exclusively seen in HLH group and three patients developed ARDS. Two patients each in HLH and non-HLH group had shock requiring vasoactive therapy in addition to fluids. Mean days of ICU and hospital stay were higher in HLH group vs. non-HLH group but not statistically significant (6.4 vs. 4.4; p-value 0.32 and 8.44 vs. 5.6; p-value 0.18 days, respectively). All children in HLH group received steroids as per HLH protocol. In the HLH group, seven survived while two died. In the non-HLH group, all five patients survived. We concluded that IL2R levels are high in dengue HLH and useful for definitive diagnosis. Early recognition of this condition in severe dengue and prompt steroid therapy improves chances of better outcome.

Study of secondary hemo-phagocytic lympho-histiocytosis in children at a tertiary centre

Background: Hemophagocytic lympho-histiocytosis (HLH) is fatal condition characterised by aggressive immune activation, dysregulation and up regulation of inflammatory cytokines leading to uncontrolled activation of T-cells, defective granule mediated cytotoxicity. HLH is classified into primary and secondary HLH.Methods: This is retrospective study of case-records of children who fulfilled criteria of HLH-2004 guidelines from November 2016 to November 2020.Results: Total number of patients with HLH was 33, excluding 4 cases of primary HLH, 29 cases met the inclusion criteria. 19 (65.5%) were children less than 5 years of age at the time of diagnosis. Six (20.7%) children were between 6 to 10 years and the rest 4 (13.8%) ten years. Average age at presentation was 4.93 years. Male to female ratio was 0.8 to 1. Fever was the chief complaint present in 29 (100%) of cases. Laboratory parameters showed anaemia, thrombocytopenia, hyper-ferritinemia and hypertriglyceridemia in all 29 (100%) cases. CRP elevated in 28 (96.6%) cases. Infections found in 29 (100%) of cases, bacteria in 19 (65.5%), viral in 10 (34.5%). Mortality seen in 11 (37.9%) cases. Average time of diagnosis from admission was 5.6 days. 4 children out of 11 had dengue as cause for secondary HLH and 4 had bacterial sepsis one each CMV, scrub typhus and SLE. Following factors affected the outcome by multivariate analysis, coagulopathy, elevated liver enzymes, bone marrow biopsy and immunosuppressive therapy.Conclusions: HLH should be considered in differential diagnosis of children with sepsis. High index of suspicion for HLH with early initiation of treatment should be considered for better outcome.

Neurological involvement in secondary hemophagocytic lymphohistiocytosis in children.

To describe neurological characteristics and CNS involvement on MRI in secondary hemophagocytic lymphohistiocytosis (sHLH) and differentiate it from primary hemophagocytic lymphohistiocytosis (pHLH) and acute disseminated encephalomyelitis (ADEM). Nine children with sHLH who had neurological symptoms were retrospectively included. Characteristics of brain MRI were compared to those of 15 children with pHLH and neurological involvement and 44 children with ADEM. Three children (33%) presented with isolated neurological symptoms. Neurological signs occurred within one month following Epstein-Barr virus primary infection or systemic juvenile arthritis exacerbation in 8 patients (89%). Eight children (89%) had MRI lesions. sHLH MRI lesions were distinct of those of pHLH by morphology and signal with more frequent hyposignal intensities on T1-weighted sequences (p=0.01) and well-defined and less fuzzy lesions (p=0.03). All patients survived and one patient presented severe motor and cognitive disability. Neurological symptoms of sHLH are non-specific and their outcome is favorable in most of the children. MRI at onset may help to differentiate this condition from pHLH.

Screening of hemophagocytic lymphohistiocytosis in children with severe sepsis in pediatric intensive care.

We sought to screen for clinical and laboratory features of hemophagocytic lymphohistiocytosis among pediatric patients with severe sepsis. We conducted a retrospective study that analyzed the clinical and laboratory data of 70 pediatric patients who died of severe sepsis. Medical records were revised for the presence of fever, splenomegaly, pancytopenia, hyperferritinemia, hypertriglyceridemia, and hypofibrinogenemia. Soluble CD25 was measured in stored samples. Patients' ages ranged between 0.5 and 11 years with median (interquartile range) 2 (1-5). All patients had fever (≥38.5 °C) and pancytopenia, 58 (82.9%) hepatosplenomegaly, 36 (51.4%) lymphadenopathy, 37 (52.9%) had ferritin >500 ng/ml, 20 (28.6%) had fibrinogen <1.5 mg/ml, 14 (20%) had fasting triglycerides >264 mg/dl while 5 (7.1%) had soluble CD25 >2400 U/ml. Twenty-five (35.7%) patients fulfilled at least 5/6 of the hemophagocytic lymphohistiocytosis-2004 diagnostic criteria. Multivariate backward binary logistic regression analysis revealed lymphadenopathy as an independent predictor for hemophagocytic lymphohistiocytosis criteria fulfilment with odds ratio of 23.9. Fibrinogen had the best performance in discriminating hemophagocytic lymphohistiocytosis fulfilling from non-fulfilling groups (cut-off value: <1.8 mg/ml), followed by ferritin/erythrocyte sedimentation rate ratio (cut-off value: >17). There is a significant clinical and laboratory overlap between hemophagocytic lymphohistiocytosis and severe sepsis, making the syndromes difficult to distinguish. The use of current hemophagocytic lymphohistiocytosis-2004 diagnostic criteria should be applied cautiously in those patients.

Polymorphisms and haplotypes of IL2RA, IL10, IFNG, IRF5, and CCR2 are associated with Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis in children.

Cytokine storms are central to the development of Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH). Previous studies have shown that single-nucleotide polymorphisms (SNPs) of cytokine genes may be associated with the development of EBV-HLH in children. As such, we investigated the association between susceptibility to EBV-HLH in children and SNPs and haplotypes of genes encoding interleukin-2 receptor subunit alpha (IL2RA), interleukin-10 (IL10), interferon gamma (IFNG), interferon regulatory factor 5 (IRF5), and C-C chemokine receptor 2 (CCR2). Sixty-six children with EBV-HLH and 58 healthy EBV-seropositive controls were enrolled in this study. SNPs of IL2RA rs2104286, rs12722489, and rs11594656; IL10 rs1800896, rs1800871, and rs1800872; IFNG rs2430561, IRF5 rs2004640, and CCR2 rs1799864 were assayed and genotyped using the SNaPshot technique. Frequencies of the A allele of IL2RA rs2104286 and IL10 rs1800896, and C allele of IL-10 rs1800872 were significantly higher in the EBV-HLH group than in the control group. The AA genotype of IL2RA rs2104286 and IL10 rs1800896, and the CC genotype of IL10 rs1800872 might be associated with a significantly high risk of EBV-HLH. However, the frequencies of genotypes and alleles of IL2RA rs2104286, IL10 rs1800871, IFNG rs2430561, IRF5 rs2004640, and CCR2 rs1799864 were similar in both groups. Additionally, IL2RA AGT (rs2104286-rs12722489-rs11594656) and IL10 ACC (rs1800896-rs1800871-rs1800872) haplotypes were also associated with an increased risk of EBV-HLH. SNPs of IL2RA rs2104286, IL10 rs1800896 and rs1800872 and the haplotypes of IL2RA AGT and IL10 ACC were highly associated with susceptibility to EBV-HLH in children.

Hemophagocytic Lymphohistiocytosis in Children with Chronic Granulomatous Disease—Single-Center Experience from North India

Chronic granulomatous disease (CGD) is an inherited defect in components of the nicotinamide adenine dinucleotide phosphate oxidase complex that results in potential life-threatening infective and noninfective complications. Hemophagocytic lymphohistiocytosis (HLH) is an unusual but important inflammatory complication of CGD. Optimal management strategies have not yet been identified in children with CGD who develop HLH. To analyze clinical and laboratory features of HLH in CGD from a tertiary-care center in North India. A retrospective review of medical records of children with CGD diagnosed in the last 20 years was performed. Clinical and laboratory features of children with CGD who developed HLH were analyzed. Of 80 patients diagnosed with CGD, 5 (6.25%) had evidence of HLH. All 5 were males; 4 had X-linked CGD and 1 had autosomal recessive CGD (NCF2 defect). Two children with CGD had HLH as the predominant presenting manifestation mimicking the clinical presentation of congenital HLH. Infectious triggers identified were bloodstream infections (n= 3) (Candida albicans, Burkholderia cenocepacia, Francisella noatuensis), pneumonia (n= 4), and splenic abscess (n= 1). We document the first human infection with a fish pathogen, F.noatuensis, in a child with X-linked CGD. Although mortality was seen in 3 children who received only intravenous (IV) immunoglobulin therapy, the other 2 who received IV methylprednisolone pulse therapy survived. HLH can be a presenting manifestation of CGD, and workup for CGD must be considered in children with HLH. Early recognition with optimal management of both infectious trigger and HLH is very important to prevent mortality.