Investigation of Ferritin in Critically Ill Patients With Hemophagocytic Lymphohistiocytosis

Study Overview
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Brief Summary
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Retrospective analysis of ferritin, outcome and HLH-criteria in critically ill patients.

Detailed Description
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The study is a retrospective register study of critically ill patients from Charité - Universitätsmedizin Berlin during 2000 and 2016 that had at least one measurement of plasma ferritin. Outcome, underlying diagnoses and HLH-2004 criteria (Henter JI et al. 2007) will be analyzed and the HScore of these patients will be calculated (Fardet L et al. 2014). All recorded data of the specific admission term in ICU will be used for the analysis. No follow-up of the patients after discharge will be performed in this study. The study does not involve any randomization or any drug testing. Update 2019: We expanded our database for the years until 2018 and also for the surgical and medical ICUs of the Charité - Universitätsmedizin Berlin (from 256 to 2623 patients). Update 2022: A systematic literature search will be performed to find suitable validation cohorts for multicenter validation of optimized HLH diagnostic criteria, which are calculated based on our data (new secondary endpoint).

Official Title
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The Prognostic and Diagnostic Value of Ferritin in Critically Ill Patients With Special Focus on Underlying Hemophagocytic Lymphohistiocytosis

Conditions
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Hemophagocytic Lymphohistiocytosis (HLH), Macrophage Activation Syndrome (MAS), Hemophagocytic Syndromes

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: male and female patients at least one measurement of plasma ferritin Exclusion Criteria: -age below 18 years

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Critically ill patients<br>Male and female critically ill patients admitted to the Charité - University Medicine Berlin during 2000 and 2018. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mortality | A retrospective analysis of patients with available charts to determine the outcome whether patients survived the ICU or died. | Participants will be followed up for the duration of hospital stay, an expected average of two months | 
| Probability of having undiagnosed Hemophagocytic lymphohistiocytosis (HLH) | Retrospective analysis of available charts, underlying diagnoses, findings and blood values: HLH-2004 criteria (Henter JI et al. 2007) and HScore (Fardet L et al. 2014) | The participants will be followed up for the duration of hospital stay, an expected average of two months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnoses | Retrospective analysis of available charts and underlying diagnoses | Participants will be followed up for the duration of hospital stay, an expected average of two months | 
| Intensive care unit stay | Retrospective analysis of available charts and duration of ICU stay | Participants will be followed up for the duration of intensive care unit stay, an expected average of one week | 
| Improving HLH diagnostic criteria including multicenter validation | Sensitivity and specificity of HLH diagnostic criteria should be improved by calculating different cutoffs of HLH-2004 criteria. Combinations with highest sensitivity and specificity will be validated in published cohorts of HLH testing for sensitivity and specificity. | Participants will be followed up for the duration of intensive care unit stay, an expected average of one week | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ferritin, Hemophagocytic lymphohistiocytosis (HLH), Critically ill patients, intensive care unit (ICU), Outcome, Diagnosis