Serum Ferritin as a Prognostic Marker of Sepsis in Critically Ill Patients – A Retrospective Study

INTRODUCTION: ICU (Intensive Critical Care Unit) needs better prognosticating parameters for sepsis as it is a major issue for global health, impacting 48.9 million people and causing 11 million deaths in 2017. The natural course of illness of these patients is complicated with systemic inflammation causing MODS (Multi Organs Dysfunction) which commonly contribute to mortality in ICU. It has many good markers but ferritin has never been used for prognostication.(1,2) OBJECTIVES: To study Ferritin as a poor prognostic marker among the critically ill patients admitted to the intensive care unit. MATERIALS AND METHODS: A retrospective data collection of 133 patients admitted in Medicine ICU was done over a period of 6 months. Inclusion criteria included: a. Septic patients admitted to the General Medicine ICU. b. Diagnosis of sepsis confirmed using Sepsis 3.0 definition, which requires the presence of infection and a Sequential Organ Failure Assessment (SOFA) score ≥ 2 points. All data were collected using a standard form which includes: Age, Sex, Number of ICU days, Comorbidity, SOFA, site of infection, Suspected or probable infection, MODS, Serum Ferritin, Number of Ventilator days, presence of shock, uses of inotropes, Days in ICU, 28-day mortality, Chronic illnesses. Data were analysed using mean, median, mode and standard deviation for continuous variables, and frequency and percentage for discrete variables. Pearson rank correlation and chi-square test were used to find a correlation between the patient profile and ferritin level.(3,4) RESULTS: A significant percentage of individuals, 39.8%, exhibited ferritin levels surpassing 1500 ng/mL. The second largest group, accounting for 28.6%, exhibited ferritin levels within the 0–500 ng/mL range. Furthermore, 20.3% exhibited 500–1000 ng/mL, and 11.3% were in the 1000–1500 ng/mL range. The average ferritin value was 1124.33 ng/mL, and the median was 1009 ng/mL, suggesting elevated ferritin levels in most patients. A chi-square value of 122.453 and a p-value below 0.05 demonstrated a significant correlation between ferritin levels and SOFA scores. Higher ferritin was associated with more severe SOFA scores and greater organ dysfunction.(5,6) 0–500 ng/mL: 100% survival; 500–1000 ng/mL: 100% survival; 1000–1500 ng/mL: 80% mortality; >1500 ng/mL: 100% mortality. The Chi-Square value for mortality association was 123.395 (p = 0.000), confirming the statistical significance. Patients with ferritin >1500 ng/mL had a Hazard Ratio (HR) of 4.4 compared to those with 1000–1500 ng/mL, indicating a 4.4-fold increase in mortality risk.(5,7) DISCUSSION/CONCLUSION: The findings indicate a distinct relationship between elevated ferritin levels and the heightened severity of organ dysfunction as assessed by SOFA scores. This supports ferritin as a potential marker of illness severity in critical care. Elevated ferritin may indicate greater likelihood of significant organ impairment and poor prognosis, aligning with prior research into inflammation and ferritin's role in critical illness.(1–3,6)