Kranz, Lincoln A.

There have been no large comparisons of the clinical and laboratory features of familial neonatal hemophagocytosis (f-nHLH) and infectious neonatal hemophagocytosis (i-nHLH). The objectives of this study were the following: (1) Describe the demographic, diagnostic, and clinical features of patients with familial nHLH (F-nHLH) and infectious HLH (i-nHLH). (2) Compare key variables between f-nHLH and i-nHLH. (3) Compare the clinical outcomes of f-nHLH and i-nHLH. (4) Summarize literature on cytokine levels in patients with nHLH. Data from a previously published nHLH meta-analysis report were used to describe and compare features of infants with f-nHLH versus i-nHLH. Variables were tested with the χ 2 test or Fisher exact test, Cochran-Armitage test, independent 2-sample t test, or Wilcoxon rank-sum test as appropriate. Odds ratios were calculated for any comparison with a P -value of <0.05. Data extracted from 99 cases of f-nHLH and 54 cases of i-nHLH were included in this analysis. Infants with f-HLH met HLH criteria at the following rates: fever (84%); organomegaly (100%); pancytopenia (75%); hypofibrinogenemia (84%); hypertriglyceridemia (48%); hypofibrinogenemia or hypertriglyceridemia (82%); hemophagocytosis (81%); hyperferritinemia (99%); low or absent NK cell activity (91%); and elevated soluble CCD25 (91%). Infants with i-nHLH had higher median ferritin levels (22,537 ng/mL) than infants with f-nHLH (7587 ng/mL) ( P =0.072). Infants with f-nHLH had higher rates of symptoms in utero, preterm birth, family history of HLH, and family history of infant death. The overall survival among infants with familial nHLH was lower than infectious nHLH ( P =0.037). Management of nHLH requires rapid diagnosis and prompt treatment, as current literature suggests nHLH has high mortality rates. Distinguishing between familial and infectious causes of nHLH can aid in determining the correct treatment of choice.

Abstract Background Neonatal hemophagocytic lymphohistiocytosis (nHLH), defined as HLH that presents in the first month of life, is clinically devastating. There have been few large descriptive studies of nHLH. Objectives The objective of this study was to perform a meta‐analysis of published cases of nHLH. Methods A comprehensive literature database search was performed. Cases of HLH were eligible for inclusion if clinical analysis was performed at age ≤30 days. Up to 70 variables were extracted from each case. Results A total of 544 studies were assessed for eligibility, and 205 cases of nHLH from 142 articles were included. The median age of symptom onset was day of life 3 (interquartile range [IQR]: 0–11, n = 141). Median age at diagnosis was day of life 15 (IQR: 6–27, n = 87). Causes of HLH included familial HLH (48%, n = 99/205), infection (26%, n = 53/205), unknown (17%, n = 35/205), macrophage activation syndrome/rheumatologic (2.9%, n = 4/205), primary immune deficiency (2.0%, n = 5/205), inborn errors of metabolism (2.4%, n = 5/205), and malignancy (2.0%, n = 4/205). Fever was absent in 19% ( n = 28/147) of all neonates and 39% ( n = 15/38) of preterm neonates. Bicytopenia was absent in 26% ( n = 47/183) of patients. Central nervous system (CNS) manifestations were reported in 63% of cases ( n = 64/102). Liver injury (68%, n = 91/134) and/or liver failure (24%, n = 32/134) were common. Flow cytometry was performed in 22% ( n = 45/205) of cases. Many patients (63%, n = 121/193) died within the period of reporting. Discernable values for HLH diagnostic criteria were reported between 30% and 83% of the time. Conclusions Evaluation of nHLH requires rapid testing for a wide range of differential diagnoses. HLH diagnostic criteria such as fever and bicytopenia may not occur as frequently in the neonatal population as in older pediatric populations. Neurologic and hepatic manifestations frequently occur in the neonatal population. Current reports of nHLH suggest a high mortality rate. Future publications containing data on nHLH should improve reporting quality by reporting all clinically relevant data.

Background: Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of pathologic immune activation and uncontrolled inflammation. Neonatal HLH (nHLH), defined as HLH that presents in the first month of life, is clinically devastating. nHLH is estimated to comprise 10% of familial HLH (fHLH) diagnoses. There have been few, large descriptive studies of nHLH. Objectives: The primary objective of this study was to perform a scoping review and descriptive analysis of published cases of nHLH. The secondary objective of this study was to assess the reporting quality of published nHLH cases. Methods: A comprehensive literature database search was performed. Cases of HLH were eligible for inclusion if clinical analysis was performed at age &lt; 30 days. As many as 70 variables were extracted from each case. Frequencies and percentages of variables reported per case in the articles included were provided. Qualitative variables were summarized by frequency and percentage. Quantitative variables which were not approximately normally distributed were summarized with median and interquartile range (IQR). Results: 544 studies were assessed for eligibility. Studies were excluded if they did not discuss nHLH (n=280), aggregated nHLH patient data with all ages (n=83), provided insufficient detail and/or data describing nHLH (n=28), and for other reasons (n=8).205 cases of nHLH from 142 articles were included. Cases were published from 31 countries from 1985-2023. Primary presenting features included fever (38.1%, n=67/176), organomegaly (11.9%, n=21/176) respiratory distress (11.4%, n=20/176), jaundice (4.5%, n=8/176), and signs of bleeding (3.4%, n-6/176). Symptoms began in utero in 20 patients (n=20/161). The median age of symptom onset was day of life (DOL) 3 (IQR: 0-14) (n=141). Median age at diagnosis was DOL 15 (IQR: 6-27) (n=87). The median time from initial evaluation to initiation of HLH therapy was 8 days (IQR: 3-14) (n=53). The frequency of HLH criteria and criteria median values are summarized in Table 1. The median number of diagnostic criteria met by patients were 5/8 (IQR: 4, 6). CNS manifestations were reported in 62.7% of cases (n=64/102). Skin manifestations were reported in 75.4% of cases (n=52/69). Liver injury (67.9%, n=91/134) and/or liver failure (23.9%, n=32/134) were common. Infections were reported in 46.7% of patients (n=70/150). Causes of nHLH included familial/inherited disease (46.8%, n=96/205), infection (26%, n=53), macrophage activation syndrome (2.9%, n=6), primary immunodeficiency (2.9%, n=6), inborn error of metabolism (2.4%, n=5), and malignancy (2%, n=4). Diagnosis was made using clinical and laboratory features (82.4%, n=169/205), gene panel (16.1%, n=33/205), sanger sequencing (1.0%, n=2/205), and ultra-rapid whole genome sequencing (0.5%, n=1/205). Genetic causes of fHLH included mutations in PRF1, STX11, STXBP2, UNC13D, NOCAR-H, and XIAP. The majority of patients (62.7%, n=121/193) died within the period of reporting. The estimated median survival time from nHLH onset of symptoms was 83 days. Only 4.4% (n=9/205) of studies reported complete data to calculate an H-score. Studies reported discernable values for HLH diagnostic variables at the following frequencies: temperature (71.7%), organomegaly (82.9%), hemoglobin (69.3%), thrombocytopenia (82.4%), neutrophils (55.1%), fibrinogen (64.4%), triglycerides (5.5%), hemophagocytosis (73.2%), ferritin (71.2%), low/absent NK cell activity (33.2%), and sIL2R (29.3%). Other clinically relevant variables such as the presence or absence of skin manifestations (33.7%), and CNS manifestations (49.8%) frequently went unreported. There were many cases that made a categorical description of a lab value (e.g., thrombocytopenia) without providing an absolute value (e.g., platelets level). Conclusions: This is the largest aggregated study of nHLH presentations, diagnostic criteria, clinical trajectory, and etiologic diagnoses. Neurologic, dermatologic, and hepatic manifestations occur in the neonatal population. Current reports of nHLH suggest a grim prognosis. Future publications containing data on nHLH should report all clinically relevant variables. Studies looking at multiple patients in aggregate should provide supplemental information with detailed nHLH cases.

Background: Nasopharyngeal (NP) swabbing is a technique that is commonly used to test pediatric patients for viral infections with increased use during the coronavirus disease 2019 pandemic. Complications from NP swabbing are rare and seem to occur more frequently in patients at risk of bleeding. Little is known about institutional or individual practices and experiences with NP swab testing in pediatric patients with risk factors for bleeding. Methods: We conducted a survey study of pediatric hematology/oncology (PHO) attending physicians to assess practices and experiences with NP swab testing in pediatric patients with thrombocytopenia and/or on anticoagulation. Results: There were 130 total respondents (5.6%, n = 130/2327) from 6 countries. Relatively few respondents (n = 17/130, 13.1%) reported that their institution had a policy specifying a lower-level platelet cutoff for patients undergoing NP swabbing. The median platelet cutoff below which NP swabs are not performed according to existing policies is 30,000×10(9)/L (interquartile range: 20,000 to 40,000). The median cutoff based on the opinion of the respondents was 10,000 (interquartile range: 10,000 to 20,000). There were 24 episodes of epistaxis among PHO patients that were NP swabbed; many adverse events (56.5%, n = 13/23) were described as persistent, severe, and/or required intervention. Three reported cases of epistaxis with anticoagulation or antiplatelet therapy occurred in patients with concomitant thrombocytopenia. Only 1 respondent (n = 1/130, 0.7%) reported an institutional policy for limiting NP swabs in patients on anticoagulant therapy. NP (66.9%) and nares (33.1%) were the most common sources of coronavirus disease 2019 testing that were reported. Conclusion: A small percentage of institutions in this survey have a policy restricting NP swabs in PHO patients. The discrepancy between lower platelet cutoffs proposed by experts and institutional policy suggests that existing policies may be too conservative. Expert guidelines are needed on this topic. Other bleeding risk factors (eg, aspirin use and von Willebrand disease) should be considered in policies and guidelines.