Differential Diagnosis for Vasculitis and Fever

The following differential diagnosis is organized into categories to help guide the thought process:

• Single Most Likely Diagnosis

  • Giant Cell Arteritis (GCA): This is a common form of vasculitis that often presents with fever, headache, and visual disturbances in individuals over 50 years old. The presence of fever along with symptoms like temporal headache, jaw claudication, and visual loss makes GCA a leading consideration.

• Other Likely Diagnoses

  • Polyarteritis Nodosa (PAN): A medium-vessel vasculitis that can present with fever, weight loss, and symptoms related to the affected organs, such as renal impairment or neurological manifestations.
  • Kawasaki Disease: Although more common in children, it can occur in adults and presents with fever, rash, lymphadenopathy, and desquamation of the hands and feet, along with vasculitis of medium-sized arteries.
  • Eosinophilic Granulomatosis with Polyangiitis (EGPA): Formerly known as Churg-Strauss syndrome, this condition is characterized by asthma, eosinophilia, and vasculitis affecting multiple organ systems, often presenting with fever.
  • Granulomatosis with Polyangiitis (GPA): Previously known as Wegener's granulomatosis, GPA is a form of vasculitis that affects small- to medium-sized vessels and can present with fever, respiratory symptoms, and renal involvement.

• Do Not Miss Diagnoses

  • Infective Endocarditis: Although not a primary vasculitis, it can cause vasculitic-like symptoms due to septic emboli and should be considered, especially in patients with a history of valvular heart disease or intravenous drug use.
  • Malignancy-associated Vasculitis: Certain cancers can be associated with vasculitis, and missing this diagnosis could delay appropriate cancer treatment.
  • ANCA-associated Vasculitis (AAV): This includes conditions like GPA, EGPA, and microscopic polyangiitis. Missing AAV could lead to delayed treatment and significant morbidity.

• Rare Diagnoses

  • Behçet's Disease: A form of vasculitis that can affect vessels of all sizes and is characterized by recurrent oral ulcers, genital ulcers, and uveitis, along with systemic symptoms like fever.
  • Cogan Syndrome: A rare disorder characterized by vasculitis and inflammation of the eyes and ears, which can also present with fever and systemic symptoms.
  • Relapsing Polychondritis: An autoimmune disorder that can cause vasculitis, particularly affecting cartilaginous structures, and may present with fever, among other symptoms.
  • Takayasu Arteritis: A large-vessel vasculitis that primarily affects the aorta and its major branches, often presenting with fever, arthralgias, and symptoms related to vascular stenosis or occlusion.

Each of these diagnoses has distinct clinical features and requires careful consideration based on the patient's presentation, laboratory findings, and imaging studies to ensure accurate diagnosis and appropriate management.