Answer:
This clinical scenario has been addressed in previous ask the expert questions. I have pasted the answers below and
Serum sickness is a rare, but well-recognized complication of insect stings. Below are references dealing with this issue. Unfortunately, serum sickness has also occurred in association with venom immunotherapy (references noted below as well).
As you can see from two of the references below, immunotherapy was deemed successful as therapy in patients experiencing serum sickness after an insect sting, so there is evidence in the literature to support this therapy. It is somewhat a conundrum, however, since serum sickness-like reactions have been due to immunotherapy as mentioned above.
Given these facts, a decision to initiate immunotherapy in a patient who has experienced serum sickness after a sting is based purely on clinical judgment. I think one could argue either side of this issue successfully. In the past, however, I have tended not to initiate immunotherapy in patients who have presented with serum sickness-like reactions to a hymenoptera sting. But, having said this, as noted, one could clearly utilize venom immunotherapy and be supported by the small amount of literature that we have in this regard. It is an issue, as noted, that would rest on your own clinical judgment after discussing the pros and cons with your patient.
Thank you again for your inquiry and we hope this response is helpful to you.
Journal of Allergy and Clinical Immunology
Volume 84, Issue 3, September 1989, Pages 331–337
Allergic reactions after insect stings may have a delayed onset, differing from the usual immediate anaphylactic pattern. Ten patients, aged 6 to 78 years, had allergic reactions 1 to 2 weeks after an insect sting. Six patients had had multiple stings preceding the reaction. In two instances, immediate anaphylaxis also occurred. Four of the 10 patients had serum sickness-type reactions; two other patients had more severe anaphylactic symptoms, including throat edema. All patients in this group had venom-specific IgE; four of the 10 patients had serum venom-specific IgG. Eight patients subsequently received venom immunotherapy (VIT). There have been no reactions from seven re-stings. Five patients had generalized hives starting 6 to 24 hours after an insect sting. All patients in this group had venom-specific IgE; three patients have received VIT. Two other patients developed hives, one with throat edema 3 days after an insect sting. Both patients had high titers of serum venom-specific IgE; neither patient has received VIT, one patient because of extreme sensitivity. These observations suggest that after an insect sting, patients may develop delayed-onset allergic symptoms that range from typical anaphylaxis to serum sickness and are mediated by venom-specific IgE. VIT is recommended for patients with these reactions.
J Rheumatol. 1997 Jun;24(6):1195-7.
Serum sickness after wasp venom immunotherapy: clinical and biological study.
De Bandt M, Atassi-Dumont M, Kahn MF, Herman D.
Source
Service of Internal Medicine, Xavier Bichat Hospital, Paris, France.
Abstract
We describe a case of a man who developed serum sickness during wasp venom immunotherapy. Remarkable features were unusually severe neurological symptoms, multiple relapses in the absence of rechallenge, parallel course between clinical symptoms, serum levels of specific reagins and their antibodies, and a dramatic response to plasma exchange therapy. Desensitization is widely used and can cause a wide range of adverse effects; however, systemic vasculitis is a very rare complication and we are not aware of any case similar to ours, with serum sickness after injection of highly purified hymenoptera antigen. Clinicians should be aware of such a possibility.
Ann Allergy Asthma Immunol. 1995 Dec;75(6 Pt 1):522-4.
Serum sickness reaction following multiple insect stings.
Lazoglu AH, Boglioli LR, Taff ML, Rosenbluth M, Macris NT.
Source
Department of Medicine, Lenox Hill Hospital, New York, New York, USA.
Abstract
Background: Anaphylaxis is the most common systemic allergic reaction caused by stinging insects. Serum sickness reactions occur much less frequently.
Objective: To determine the level of venom-specific IgG and IgE antibodies during and after a serum sickness reaction to vespid venom.
Methods: Case report; ELISA determination of venom-specific IgG and IgE; complement levels and tests for immune complexes were performed.
Results: We report the case of a 66-year-old woman who developed a serum sickness reaction nine days after receiving multiple vespid stings. She developed urticaria, angioedema, fever, and arthralgias. She had elevated IgG and IgE venom-specific titers which declined during the recovery phase. Complement levels were normal and tests for immune complexes were negative. She was successfully treated with venom-specific immunotherapy without any serum sickness reaction.
Conclusions: A serum sickness reaction with elevated venom-specific IgG and IgE is reported with successful immunotherapy.
I hope this has been helpful.
Andrew Murphy MD FAAAAI