Serum sickness

Serum sickness
Video explanation
Specialty	Immunology
Symptoms	Fever, rash, joint pain
Duration	Few weeks
Causes	Certain vaccines (such as rabies), antivenom, immunomodulators (such as rituximab or thymoglobulin)
Diagnostic method	Blood tests, skin biopsy
Differential diagnosis	Serum sickness–like reaction (SSLR), acute rheumatic fever, Kawasaki disease, Dengue, Stevens-Johnson syndrome, IgA vasculitis
Treatment	Stopping the cause, antihistamines, NSAIDs, steroids, plasma exchange
Prognosis	Good
Frequency	Rare

Serum sickness is a type of allergic reaction to non-human proteins. Symptoms commonly include fever, rash, and joint pain. It generally occurs 7 to 14 days after exposure and symptoms can last for a few weeks. Complications are rare, though repeated episodes of serum sickness may potentially result in kidney failure.

It most commonly occurs as a result of certain vaccines (such as rabies), antivenom, and immunomodulators (such as rituximab and thymoglobulin). The underlying mechanism involves hypersensitivity, specifically immune complex hypersensitivity (type III). Diagnosis may be supported by urine tests, blood tests, and a skin biopsy.

Treatment often simple involves stopping whatever is causing the condition. Antihistamines and NSAIDs may be used to improve symptoms. For more severe symptoms steroids may be used. If this is not effective plasma exchange may be an option. Outcomes are generally excellent.

Serum sickness is rare. It; however, may occur in up to 27% of people treated with thymoglobulin post kidney transplant. It was first described in detail by Clemens von Pirquet and Béla Schick in 1905.

Signs and symptoms

a) Multiple itchy and red and some targeted lesions are seen on lower extremities b) the injection site on the back

Signs and symptoms can take as long as 14 days after exposure to appear, and may include signs and symptoms commonly associated with hypersensitivity or infections.

• rashes
• itching
• joint pain (arthralgia), especially finger and toe joints
• fever, as high as 40 °C and usually appears before rash
• lymphadenopathy (swelling of lymph nodes), particularly near the site of injection, head and neck
• malaise
• hypotension (decreased blood pressure)
• splenomegaly (enlarged spleen)
• glomerulonephritis
• protein in the urine
• blood in the urine
• shock

Causes

When an antiserum is given, the human immune system can mistake the proteins present for harmful antigens. The body produces antibodies, which combine with these proteins to form immune complexes. These complexes precipitate, enter the walls of blood vessels, and activate the complement cascade, initiating an inflammatory response and consuming much of the available complement component 3 (C3). The result is a leukocytoclastic vasculitis. This results in hypocomplementemia, a low C3 level in serum. They can also cause more reactions resulting in typical symptoms of serum sickness.

Antitoxins and antisera

Serum sickness can be developed as a result of exposure to antibodies derived from animals. These sera or antitoxins are generally administered to prevent or treat an infection or envenomation.

Medications

Some of the drugs associated with serum sickness are:

• allopurinol
• barbiturates
• captopril
• cephalosporins
• crofab
• griseofulvin
• penicillins
• phenytoin
• procainamide
• quinidine
• streptokinase
• sulfonamides
• rituximab
• ibuprofen
• infliximab
• oxycodone

Others

Allergenic extracts, hormones and vaccines can also cause serum sickness. However, according to the Johns Hopkins Bloomberg School of Public Health, currently routinely recommended vaccinations to the general population in the U.S have not been shown to cause serum sickness. [1] Archived 2018-10-28 at the Wayback Machine

Diagnosis

Diagnosis is based on history given by patient, including recent medications.

Differential diagnosis

Serum sickness–like reaction (SSLR) is a similar illnesses that arise from the introduction of certain non-protein substances, such as penicillin.

Prevention

Avoidance of antitoxins that may cause serum sickness is the best way to prevent serum sickness. Although, sometimes, the benefits outweigh the risks in the case of a life-threatening bite or sting. Prophylactic antihistamines or corticosteroids may be used concomitant with the antitoxin. Skin testing may be done beforehand in order to identify individuals who may be at risk of a reaction. Physicians should make their patients aware of the drugs or antitoxins to which they are allergic if there is a reaction. The physician will then choose an alternate antitoxin if it's appropriate or continue with prophylactic measures.

Treatment

With discontinuation of the offending agent(s), symptoms usually disappear within 4–5 days.

Corticosteroids, antihistamines, and analgesics are the main line of treatment. The choice depends on the severity of the reaction.

Use of plasmapheresis has also been described.

See also

• Arthus reaction

External links

Classification	ICD-10: T80.6 ICD-9-CM: 999.5 MeSH: D012713 DiseasesDB: 11970
External resources	MedlinePlus: 000820 eMedicine: med/2105

• Serum sickness-like reactions Archived 2010-09-04 at the Wayback Machine