International

Renal Anaemia in the news

Contact allergies prevalent in dialysis patients

• 10 March 2009
• Reuters Health

NEW YORK (Reuters Health) - Contact sensitizations occur frequently in hemodialysis patients and are associated with vascular access conditioning protocols, especially the use of lidocaine-prilocaine anesthetic cream (EMLA), researchers from France found in a prospective single-center study.

This study, Dr. Marie A. Richard from Hopital Sainte Marguerite in Marseille told Reuters Health, shows that "eczema localized on the site of arteriovenous fistula is common among dialyzed patients but the associated risks are limited; no serious infectious events, no systemic reactions follow contact sensitization."

Study subjects included 75 patients who had been on dialysis for a mean of 3.8 years. Skin tests were carried out using 53 allergens, including 25 allergens from the standard European Environmental and Contact Dermatitis Research Group series, 10 additional tests from the French Dermatology and Allergology Research Group (GERDA), and a battery of antiseptics and other dialysis-specific allergens.

According to the team's report in the February issue of the journal Allergy, 19 patients (25%) had one or more positive skin patch tests; the mean number of positive skin tests was 2.1 and the maximum number was 6.

Thirteen patients (17%) had at least one positive skin test potentially linked to one or more products used during vascular access conditioning and preparatory procedures, most commonly EMLA cream. Eight patients (10.7%) had positive patch tests to EMLA cream. "This was clinically relevant for seven of these patients," the investigators report.

This study, Dr. Richard said, "highlights the high frequency of contact sensitization with EMLA."

EMLA cream was the "primary allergen," the investigators note in their report, as 9% of the population developed delayed sensitization after an average of 4 years of exposure.

The main risk factors for delayed hypersensitivity to EMLA cream appear to be "application on damaged skin and repeated and prolonged use under bandages or dressings on the same cutaneous area," they point out.

Seven percent of the patients had positive skin test results to antiseptics, of which 4% were allergic to povidone-iodine. None of the patients had positive patch tests for chlorhexidine, an antiseptic widely used in the hemodialysis department.

Sixteen percent of patients had positive test results to excipients and preservatives, most commonly sodium metasulphite and Euxyl K400.

Dr. Richard and colleagues conclude that testing for sensitization in hemodialysis patients "could help to adapt haemodialysis procedures, for example by using a minimum amount of topical agents at the vascular access site, and 'hypoallergenic adhesives' of known composition."

Allergy 2009;64:222-228.