Differential Diagnosis for Raised Ferritin During Infection

When ferritin levels are elevated during an infection, it's crucial to consider a range of potential diagnoses due to the nonspecific nature of this marker. Ferritin can be elevated in various conditions, including infections, inflammatory diseases, and malignancies. Here's a categorized differential diagnosis:

• Single Most Likely Diagnosis
  • Sepsis or Severe Infection: Elevated ferritin can be seen in the context of severe infections or sepsis as part of the acute phase response. The body's inflammatory response to infection can lead to increased ferritin levels.
• Other Likely Diagnoses
  • Hemophagocytic Lymphohistiocytosis (HLH): This is a condition characterized by an overactive and inappropriate immune response, often triggered by infections. It leads to elevated ferritin levels, among other symptoms.
  • Macrophage Activation Syndrome (MAS): Similar to HLH, MAS is a condition where the immune system overreacts, leading to high ferritin levels. It's often associated with autoimmune or inflammatory conditions but can be triggered by infections.
  • Inflammatory Conditions: Conditions like rheumatoid arthritis, lupus, or other autoimmune diseases can cause elevated ferritin due to chronic inflammation.
• Do Not Miss Diagnoses
  • Malignant Histiocytosis: A rare but aggressive condition where histiocytes (a type of immune cell) become cancerous. It can present with very high ferritin levels and is critical to diagnose early.
  • Lymphoma: Certain types of lymphoma can cause elevated ferritin levels, either due to the disease itself or as a result of associated inflammatory responses.
• Rare Diagnoses
  • Porphyrias: Some types of porphyria, a group of disorders that result from a buildup of porphyrins, can lead to elevated ferritin levels, though this is less common.
  • Hyperferritinemia Cataract Syndrome: A rare genetic disorder characterized by early-onset cataracts and elevated ferritin levels without iron overload.
  • Gaucher's Disease: A genetic disorder where glucocerebroside accumulates in cells and certain organs, which can lead to elevated ferritin among other symptoms.

Each of these conditions has a different set of accompanying symptoms and diagnostic criteria. A thorough clinical evaluation, including additional laboratory tests and sometimes imaging studies, is necessary to accurately diagnose the cause of elevated ferritin levels during an infection.