Differential Diagnosis for Cytokine Storm

The combination of high interleukin levels, acute polyarthritis, and acute transverse myelitis in an appropriate setting suggests a severe inflammatory condition. Here's a differential diagnosis organized into categories:

• Single Most Likely Diagnosis

  • Hemophagocytic Lymphohistiocytosis (HLH): This condition is characterized by an overwhelming immune response, leading to high levels of inflammatory cytokines like interleukins. The presence of acute polyarthritis and transverse myelitis, along with elevated interleukin levels, could be indicative of HLH, especially in the context of a triggering event such as infection or autoimmune disease.

• Other Likely Diagnoses

  • Systemic Juvenile Idiopathic Arthritis (sJIA): This condition can present with high fever, polyarthritis, and elevated inflammatory markers, including interleukins. It is a form of arthritis that affects children and can be associated with a cytokine storm.
  • Macrophage Activation Syndrome (MAS): Often considered a complication of sJIA, MAS is characterized by an excessive activation and proliferation of T lymphocytes and macrophages, leading to a cytokine storm. It can present similarly to HLH.
  • Sepsis: Although not typically associated with polyarthritis and transverse myelitis directly, severe sepsis can lead to a systemic inflammatory response syndrome (SIRS) that might mimic some aspects of a cytokine storm, including high levels of inflammatory cytokines.

• Do Not Miss Diagnoses

  • Multiple Sclerosis (MS): While MS can cause transverse myelitis, it is less likely to be associated with acute polyarthritis and a significant elevation in interleukin levels. However, missing a diagnosis of MS could lead to inappropriate treatment and poor outcomes.
  • Neuromyelitis Optica Spectrum Disorder (NMOSD): This condition can cause transverse myelitis and, in some cases, may be associated with systemic symptoms. It is crucial to differentiate NMOSD from other causes of myelitis due to its specific treatment and prognosis.
  • Infectious Diseases (e.g., Lyme disease, viral infections): Certain infections can cause a combination of arthritis, neurological symptoms, and elevated inflammatory markers. Missing an infectious cause could lead to delayed appropriate treatment.

• Rare Diagnoses

  • Adult-Onset Still's Disease (AOSD): A rare condition characterized by high fevers, salmon-colored rash, and arthritis, AOSD can also present with elevated interleukin levels. It is a diagnosis of exclusion and should be considered in the appropriate clinical context.
  • Cytokine Release Syndrome (CRS): Typically associated with immunotherapy (e.g., CAR-T cell therapy), CRS can cause a range of symptoms from mild to life-threatening, including fever, hypotension, and organ dysfunction. It would be rare in the context described but should be considered if the patient has received relevant treatments.