Differential Diagnosis of Hyperferritinemia in Critically Ill Patients

Value of hemophagocytosis in the diagnosis of hemophagocytic lymphohistiocytosis in critically ill patients

BACKGROUND

Ferritin is an established biomarker in the diagnosis of secondary hemophagocytic lymphohistiocytosis (HLH), which is diagnosed by the HLH-2004 criteria. Among these criteria, detection of hemophagocytosis through invasive procedures may delay early life saving treatment. Our aim was to investigate the value of hemophagocytosis in diagnosing HLH in critically ill patients.

METHODS

In this secondary analysis of a retrospective observational study, we included all patients aged ≥18 years and admitted to any adult ICU at Charité-Universitätsmedizin Berlin between January 2006 and August 2018, who had hyperferritinemia (≥500 μg/L) and underwent bone marrow biopsy during their ICU course.

RESULTS

Two hundred fifty-two patients were included, of whom 31 (12.3%) showed hemophagocytosis. In multivariable logistic regression analysis, maximum ferritin was independently associated with hemophagocytosis. By removing hemophagocytosis from HLH-2004 criteria and HScore, prediction accuracy for HLH diagnosis was only marginally decreased compared to the original scores.

CONCLUSIONS

Our results strengthen the diagnostic value of ferritin and underline the importance of considering HLH diagnosis in patients with high ferritin but only four fulfilled HLH-2004 criteria, when hemophagocytosis was not assessed or not detectable. Proof of hemophagocytosis is not required for a reliable HLH diagnosis.

Inpatient recognition and management of HLH

Hemophagocytic lymphohistiocytosis (HLH) is one of the life-threatening emergencies that a hematologist may be called upon to diagnose and manage. It is a hyperinflammatory process that develops in patients with genetic abnormalities, hematologic malignancies, chronic inflammatory states, or infections. The main clinical challenges are recognizing HLH, determining whether the immune response is aberrant or appropriate, and deciding upon therapy. Patients may present with fever, central nervous system symptoms, cytopenias, or elevated liver enzymes. Recognizing HLH is challenging because its features overlap with numerous systemic disorders, thus requiring a high level of suspicion and timely investigations to confirm the diagnosis and detect the underlying trigger. Once HLH is diagnosed, careful consideration of immunosuppressive therapy's potential benefit versus harm is necessary. Such therapy can sometimes be tailored to the underlying trigger. In the acute setting, the competing pressures of completing a thorough diagnostic process (including evaluation for the presence of lymphoma and infection) and the need for expedited treatment must be balanced. During the management of an HLH patient, continuous vigilance for the presence of as-yet unrecognized disease triggers, monitoring response, and identifying emerging complications is critical. This review will discuss the recognition and management of HLH in the inpatient setting.

Atypical Adult Still's Disease Complicated by Hemophagocytic Syndrome in an Older Patient: A Case Report

Hyperferritinemia can occur in various diseases, making the differential diagnoses diverse and often fatal. The macrophage-activated syndrome (MAS) is a differential diagnosis of hyperferritinemia in which systemic macrophages are activated and cause various symptoms. Many cases are complicated by hemophagocytic syndrome, causing pancytopenia, which can be fatal. Furthermore, it is challenging to diagnose hyperferritinemia in elderly patients, and the disease may develop into a fever of unknown origin. We report the case of a 93-year-old man with aspiration pneumonia, followed by intermittent prolonged fever complicated by abnormal hyperferritinemia and leukopenia. Based on his general condition, he was diagnosed with atypical adult Still's disease and treated with steroid pulses and tocilizumab, temporarily relieving his symptoms. However, the patient eventually developed sepsis and could not be saved. Diagnosis of hyperferritinemia in the elderly population is complex and requires immediate attention. However, invasive intervention may lead to the deterioration of an elderly patient's condition. In the context of medical care for the elderly at a community hospital, it is necessary to provide comprehensive care for those in critical condition, considering the degree of invasiveness of examinations and procedures.