A new dipstick test (Allergodip®) for in vitro diagnosis of latex allergy – validation in patients with spina bifida

While there is established data on the value of various assays for determining specific immunoglobulin E (IgE) in serum, little has been reported about semi‐quantitative dipstick methods. Therefore, in a pilot study we compared a new dipstick assay (Allergodip^®) with a well‐evaluated commercial assay (Pharmacia CAP‐system^®), in terms of sensitivity and specificity, in sensitized and nonsensitized, symptomatic and non‐symptomatic patients with spina bifida. One‐hundred and thirty‐five patients with spina bifida (median age 10.8 years) were included in this study. Sixty‐nine patients (51.1%) were positive in the CAP‐system, 61 patients (45.2%) were positive in the Allergodip assay, and 67 patients (49.6%) were positive in a skin prick test with natural rubber latex milk. The concordance between the CAP‐system and Allergodip was good. Forty‐seven patients (34.8%) showed a positive response to the provocation test. The sensitivity of Allergodip was 85.1% compared with 91.5% for the CAP‐system. Specificity was 75.0% for the Allergodip assay and 70.5% for the CAP‐system. We conclude that the new dipstick test is a useful screening test for diagnosing sensitization to latex, e.g. when planning surgical interventions. However, in instances of doubtful reactions, discrepancies with clinical features or for scientific work it does not replace quantitative determination of specific IgE.