Evaluation of hyperferritinemia causes in rheumatology practice: a retrospective, single-center experience.

Hyperferritinemia may develop due to various reasons such as inflammation, infection, or malignancy. The purpose of the study to explore the prevalence and to figure out the causes of general hyperferritinemia and extreme hyperferritinemia as detected through the ferritin measurements requested by the rheumatology department. Adult patients at the age of 18 years and older with at least one serum ferritin level measurement at or above 500 ng/mL as requested by the rheumatology department between January 2010 and December 2019 were evaluated retrospectively. Hyperferritinemia was detected in 4.7% of 11,498 serum ferritin tests. The mean age of 242 patients found to have hyperferritinemia was 53.7 ± 17.1 years; of the patients, 63.2% were female, and the mean serum ferritin value was 2820 ± 5080 ng/mL. The most common cause of hyperferritinemia was rheumatological diseases with a ratio of 59.1%, which was followed by infections, iron overload, and solid malignancy. Among the rheumatologic diseases, adult-onset Still's disease (AOSD), rheumatoid arthritis, and vasculitis were the cause accounting for hyperferritinemia. Ferritin levels were significantly higher in the AOSD group compared to the other rheumatologic disease groups (p < 0.0001). While extreme hyperferritinemia (ferritin ≥ 10,000 ng/mL) rate in our cohort was 0.2%, the most common cause was AOSD (15/17). In patients with hyperferritinemia, 3 month mortality was found to be 8.7%. CRP level was identified as the only independent predictor for the 3 month mortality in all patients [OR 1.088 (95% CI 1.004-1.178), p = 0.039]. Although rheumatologic disease activation and infections are the most common causes, the other causes should also be considered for the differential diagnosis.

Hyperferritinemia and acute kidney injury in pediatric patients receiving allogeneic hematopoietic cell transplantation.

BACKGROUND: Acute kidney injury (AKI) often occurs in pediatric patients who received allogeneic hematopoietic cell transplantation (HCT). We evaluated the risk and effect of HCT-related AKI in pediatric patients. METHODS: We retrospectively studied the survival and renal outcome of 69 children 100 days and 1-year posttransplant in our institution in 2004-2016. Stage-3 AKI developed in 34 patients (49%) until 100 days posttransplant. RESULTS: The 100-day overall survival (OS) rates of patients with stage-3 AKI were lower than those without it (76.5% vs. 94.3%, P = 0.035). The 1-year OS rates did not differ markedly between 21 post-100-day survivors with stage-3 AKI and 29 without it (80.8% vs. 87.9%, P = 0.444). The causes of 19 deaths included the relapse of underlying disease or graft failure (n = 11), treatment-related events (4), and second HCT-related events (4). Underlying disease of malignancy (crude hazard ratio (HR) 5.7; 95% confidence interval (CI), 2.20 to 14.96), > 1000 ng/mL ferritinemia (crude HR 4.29; 95% CI, 2.11 to 8.71), stem cell source of peripheral (crude HR 2.96; 95% CI, 1.22 to 7.20) or cord blood (crude HR 2.29; 95% CI, 1.03 to 5.06), and myeloablative regimen (crude HR 2.56; 95% CI, 1.24 to 5.26), were identified as risk factors for stage-3 AKI until 100 days posttransplant. Hyperferritinemia alone was significant (adjusted HR 5.52; 95% CI, 2.21 to 13.76) on multivariable analyses. CONCLUSIONS: Hyperferritinemia was associated with stage-3 AKI and early mortality posttransplant. Pretransplant iron control may protect the kidney of pediatric HCT survivors.

Hyperferritinemia in Critically Ill Patients.

OBJECTIVE: Hyperferritinemia is frequently seen in critically ill patients. A rather rare though life-threatening condition related to severely elevated ferritin is hemophagocytic lymphohistiocytosis. We analyze ferritin levels to differentiate hemophagocytic lymphohistiocytosis from other causes of hyperferritinemia in a mixed cohort of critically ill patients. DESIGN: Retrospective observational study. SETTING: Adult surgical, anesthesiologic, and medical ICUs of a university hospital. PATIENTS: Critical care patients (≥ 18 yr old) admitted to any of the adult ICUs at Charité - Universitätsmedizin Berlin between January 2006 and August 2018 with at least one ferritin value and hyperferritinemia (≥ 500 µg/L). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients were categorized into hemophagocytic lymphohistiocytosis, sepsis, septic shock, and other diagnoses. These were further categorized into 17 subgroups. Hemophagocytic lymphohistiocytosis diagnosis was based on Hemophagocytic Lymphohistiocytosis-2004 criteria and the HScore. Of 2,623 patients with hyperferritinemia, 40 were considered to have hemophagocytic lymphohistiocytosis (1.52%). Maximum ferritin levels were highest in hemophagocytic lymphohistiocytosis patients compared with all other disease groups (each p < 0.001). Sepsis and septic shock patients had higher maximum ferritin levels than patients with other diagnoses (each p < 0.001). A maximum ferritin value of 9,083 µg/L was at 92.5% sensitivity and 91.9% specificity for hemophagocytic lymphohistiocytosis (area under the curve, 0.963; 95% CI, 0.949-0.978). Of all subgroups with other diagnoses, maximum ferritin levels were highest in patients with varicella-zoster virus, hepatitis, or malaria (median, 1,935, 1,928, and 1,587 µg/L, respectively). Maximum ferritin levels were associated with increased in-hospital mortality (odds ratio, 1.518 per log µg/L [95% CI, 1.384-1.665 per log µg/L]; p < 0.001). CONCLUSIONS: This is the largest study of patients with ferritin available in a mixed ICU cohort. Ferritin levels in patients with hemophagocytic lymphohistiocytosis, sepsis, septic shock, and other conditions were distinctly different, with the highest ferritin levels observed in hemophagocytic lymphohistiocytosis patients. Maximum ferritin of 9,083 µg/L showed high sensitivity and specificity and, therefore, may contribute to improved diagnosis of hemophagocytic lymphohistiocytosis in ICU. The inclusion of ferritin into the sepsis laboratory panel is warranted.