Herxheimer reaction
Classification and external resources
ICD-10	T78.2
ICD-9	995.0

The Herxheimer reaction (also known as Jarisch-Herxheimer or Herx) occurs when large quantities of toxins are released into the body as bacteria (typically Spirochetal bacteria) die, due to antibiotic treatment or rapid detoxification.

Typically the death of these bacteria and the associated release of endotoxins occurs faster than the body can remove the toxins via the natural detoxification process performed by the kidneys and liver. It is manifested by fever, chills, headache, myalgia (muscle pain), and exacerbation of skin lesions. Duration in syphilis is normally only a few hours but can be much longer, up to months or years, for other diseases, especially Lyme Disease. The intensity of the reaction reflects the intensity of inflammation present.

The Herxheimer reaction has shown an increase in inflammatory cytokines during the period of exacerbation, including tumor necrosis factor alpha, interleukin-6 and interleukin-8.^[1][2]

[edit] History

Both Adolf Jarisch,^[3] an Austrian dermatologist, and Karl Herxheimer,^[4] a German dermatologist, are credited with the discovery of the Jarisch-Herxheimer reaction. Both Jarisch and Herxheimer observed reactions in patients with syphilis treated with mercury. The reaction was first seen following treatment in early and later stages of syphilis treated with Salvarsan, mercury, or antibiotics. It is seen in 50% of patients with primary syphilis and about 90% of patients with secondary syphilis.^{[citation needed]}

The reaction is also seen in other diseases, such as borreliosis (Lyme disease^[5][6] and tick-borne relapsing fever^[7]), bartonellosis, brucellosis, typhoid fever, Myalgic Encephalomyelitis, and trichinellosis, Q fever, and cat scratch disease.^[8][9]

[edit] References

v • d • e Consequences of external causes (T66-T88, 990-999) Temperature/radiation elevated: Hyperthermia · Heat syncope · Radiation poisoning reduced: Hypothermia · Immersion foot · Chilblain Air Hypoxia/Asphyxia · Barotrauma (Aerosinusitis, Decompression sickness) · Altitude sickness/Chronic mountain sickness Food Starvation Maltreatment Physical abuse · Sexual abuse · Psychological abuse Emesis Motion sickness · Seasickness · Airsickness · Space adaptation syndrome Other Electric shock · Anaphylaxis · Angioedema Hypersensitivity (Allergy, Arthus reaction) Subcutaneous emphysema Certain early complications of trauma embolism (Air, Fat) Crush syndrome/Rhabdomyolysis Contracture/Volkmann's contracture/Compartment syndrome Complications of surgical and medical care transfusion reactions: Transfusion hemosiderosis · TRALI · TACO · TA-GvHD · FNHTR · Acute/Delayed hemolytic transfusion reaction other: Serum sickness · Malignant hyperthermia · Herxheimer reaction · Graft-versus-host disease · Tumor lysis syndrome

[edit] Sources

"Jarisch - Herxheimer"

"J-H Reaction and Lyme Disease"

"The Herxheimer Reaction"