Diagnosis of latex hypersensitivity: comparison of different methods.

A standardized diagnostic protocol for latex allergy is still lacking, although latex-related manifestations are a common health problem especially among health-care workers and patients with spina bifida. The present study was aimed to compare different in vivo (skin prick test, patch test, use test) and in vitro (specific IgE determination by CAP-Rast, basophil histamine release assay, immunoblot) methods to diagnose latex sensitization in 47 health care workers reporting latex-related manifestations. According to the established criteria, 20 subjects (42.5%) were considered as truly sensitized to latex, 18 with type I and 2 with type IV hypersensitivity. Skin prick test displayed the highest diagnostic efficiency, having higher sensitivity and specificity than specific IgE determination and use test. Patch test with rubber chemicals had a low sensitivity, but a good specificity. Basophil histamine release and immunoblot showed low sensitivity and specificity. A combination of clinical history and skin prick test should be used in order to diagnose latex allergy, except in those subjects reporting life-threatening reactions, in which in vitro specific IgE determination must be preferred. Patch testing with rubber chemicals should be reserved to selected cases. Basophil histamine release and immunoblotting can be performed for research purpose, but cannot be recommended for routine diagnostic use.