Dear Editor:
Faced with the presence of recurrent vascular access (VA) thrombosis, it is necessary to research the possibility of anomalies in the vessels or a hypercoagulable state; however, to date no case has been described of an allergic reaction during the surgical act.
21 year old male who suffered repeated premature VA thromboses before starting haemodialysis, probably related to an allergic reaction to latex. The patient was admitted to our department following two unsuccessful VA attempts. Vascular anomalies and hypercoagulable state had been ruled out. Surgery was initially successful, but after a period of a few minutes the patient developed a maculopapular pruriginous erythema along the entire manipulated venous tract and a disappearance of the fistula thrill and bruit. The problem developed subtly, and may have gone unnoticed had there not been high suspicion.
Faced with the possibility of an allergic reaction, a skin prick test was carried out, which revealed an allergy to latex (10mm papule and RAST of 43.3kU/ml [class 4] [vn <0.35kU/ml] and some fruits (pineapple, chestnut, peach, banana and melon). A test for other possible related allergens was negative (formaldehyde, ethylene oxide, chlorhexidine, mepivacaine and lidocaine).
Before performing the fifth VA, the operating theatre was prepared according to the protocol for patients allergic to latex. A right humerocephalic AVF was created, proximal to the previous functioning AVF. The patient did not show any type of reaction either during or after the procedure.
Allergy to latex is generally an immediate allergic reaction mediated by IgE. In this instance, it appeared minutes after completing the VA, with an increase in permeability and oedema in the vascular wall mediated by mastocyte degranulation and release of mediators, which were probably the cause of the premature fistula thrombosis. The patient retrospectively reported a history of oedema from balloons and preservatives, and pruritis of the tongue from some fruits. There is a high association (30-80%) between latex allergy and sensitivity to certain fruits, particularly those of tropical origin, coming from plants that are botanically unrelated to the plant from which latex is extracted.1 An association has also been described between latex and ethylene oxide, and, even though the role of ethylene antioxidant antibodies in the pathogeny of latex allergy is unknown, it seems prudent to avoid the use of products sterilised with ethylene oxide in patients who are at risk.
Those who pose a higher risk of latex allergy include workers constantly exposed to latex, people with a tendency to multiple allergic conditions and children with urological malformations who have been subjected to numerous manipulations since infancy, which was the case with our patient, who presented with a chronic secondary obstructive uropathy of the urethral valves that required a number of interventions during infancy.2 The number of operations to which a child has been subjected is clearly related to the presence of specific IgE antibodies against latex.
The population in dialysis with no previous history of allergic reactions should not be considered as at risk, despite their frequent exposure to latex.3 However, one quarter of dialysis patients may at least show a positive allergy test. These allergic reactions4,5 can have significant implications in this population, amongst which include the possibility of repeated fistula thromboses, and the consequential difficulty in attaining a functioning VA or risk in achieving a successful kidney transplant.
