MELISA can be used for metal hypersensitivity testing prior to surgery if there are indicators that an allergy may be present. For instance, skin reactions to metals, previous failed surgery and repeated unexplained infections following surgery using metal devices, pins or plates.

There are recommendations available on managing patients with potential metal hypersenstivity prior to undergoing joint arthroplasty or implantation surgery. Schalock et al. (1) recommend that patients who report cutaneous metal allergy should be tested prior to device implantation. Granchi et al. (2) also recommend patch testing for any patient with previous signs or symptoms of metal allergy. Granchi et al further add that patients with positive skin reaction should not have an implant containing the metal allergen if possible (2).

Some orthopaedic surgeons who suspect that a patient may have problems with metals for instance, nickel, will pre-test for a whole panel of metals. Titanium was traditionally thought of as bio-inert but there are increasingly reports that it may cause problems in hypersensitive patients (3). Studies show that in vitro blood lymphocyte transformation tests such a MELISA are better suited for diagnosing possible metal sensitivity than patch testing (4, 5, 6). Implant-related hypersensitivity reactions are mediated by sensitized T cells and the relationship between skin hypersensitivity and systemic hypersensitivity is ill defined. Lymphocyte transformation test sensitivity is higher than patch testing and provides quantifiable data and is highly reproducible (7).

However, even in a paper that recommends using pre-operative allergy testing in patients with self-reported metal allergy there are limitations in testing. The authors report that the frequency of allergy increases after the operation (2). Granchi et al say that the frequency of positive tests increases post-operatively, especially in those patients with failing implants or a metal-on-metal devices. Therefore, the MELISA test cannot guarantee that an allergy will not develop during in vivo, long-term, high-level metal exposure post-surgery.