Serum disease, serum sickness-like reaction (SSLR), hypersensitivity reaction, immune complex hypersensitivity (Type III).
Serum disease is caused by a special over-reaction from our immune system (Type III hypersensitivity reaction) which can occur after contact with various substances, often after injection of foreign proteins into vaccines, drugs or blood serum.
In Serum Disease, our immune system reacts to form immune complexes after vaccination, antibiotics (e.g. Trimetoprim sulfa), infections (streptococci, Hepatitis B or Hepatitis C), rituximab, infliximab (if re-treated after more than 20 weeks break, 25% will respond, less frequently with concomitant use of methotrexate).
Start: 1-2 weeks after exposure. 1-2 days after Penicillin iv Reversal few weeks later (good prognosis).
Blood samples and urine tests
- High lowering reaction (SR) and CRP
- Thrombocytopenia (mild)
- Hypoalbumin in the blood
- low complement factors C3 and C4
- Urine with Proteins and some erythrocytes (not cylinders)
Diagnosis is based on medical history (new medications, vaccines), symptoms, blood tests and disease progression (no effect on suspected infection with antibiotics)
Incorrect diagnosis (similar conditions, differential diagnoses)
- Erythema multiforme (also affects hand and foot soles)
- Lupus (Systemic Lupus Erythematosus, SLE)
- Rheumatic fever
- In children (migrant Arthritis)
- Reactive arthritis
- Steven-Johnsson syndrome og Toxic epidermal necrolysis (Blisters)
- Still's disease
- Vasculitis diseases
- viral infection
Removing cause, steroids: Prednisolone 0,5-1 mg / kg / d or methyl-prednisolone (SoluMedrol). 1-2mg / kg / d iv, antihistamine. NSAIDs and analgesics for joint pain.