Relation of latex-specific IgE titer and symptoms in patients allergic to latex.

BACKGROUND: The relation between latex-specific IgE titer and the type or total number of latex-induced symptoms has not been previously investigated. OBJECTIVE: We sought to determine the association of latex-IgE in vitro assay results with the type, number, or severity of symptoms in patients allergic to latex. METHODS: Ninety-one patients with positive histories and positive skin test responses were identified as having type I allergy. Data was collected for reported symptoms after latex exposure. Symptom severity was quantitated by 2 scores: (1) the total number of symptoms to latex exposure and (2) a symptom severity score (3 = anaphylaxis, 2 = asthma, and 1 = rhinoconjunctivitis, urticaria, or both). All subjects underwent AlaSTAT and CAP tests. RESULTS: AlaSTAT class was associated with total number of symptoms (r = 0.32, P <.001) and severity score (r = 0.33, P <.002). Similarly, CAP class was associated with both number of symptoms (r = 0.32, P <. 0001) and severity score (r = 0.31, P <.001). Among the symptoms reported, asthma had the strongest association with a positive in vitro IgE assay (odds ratio = 6.7 [95% confidence interval = 1.9, 25. 6]), followed by urticaria (odds ratio = 1.9 [95% confidence interval = 0.8, 4.6]). Contact dermatitis had no statistical association with in vitro assays in this study. AlaSTAT and CAP class correlated together significantly (r = 0.58, P <.001). CONCLUSION: Patients allergic to latex with higher AlaSTAT or CAP class were more symptomatic. Increasing class or titer also predicted more severe symptoms. Higher class of either the AlaSTAT or CAP assay to latex was strongly associated with latex-related asthma and urticaria and marginally associated with latex-related rhinoconjunctivitis.

Implementation recommendations for making health care facilities latex safe.

The problem of latex allergy is not limited to health care workers who provide direct patient care. Individuals in environmental services, dietary, engineering, and medical records departments have the potential for sensitization. Due to the significant liability that may arise from a latex-induced anaphylaxis or death, it is no longer prudent for health care facilities to ignore the problem. This article proposes practical recommendations for implementation of an institution wide latex-safe environment in health care facilities.

Diagnostic evaluation of type I latex allergy.

BACKGROUND: Latex hypersensitivity affects a significant number of health care workers. No universally accepted method for the diagnosis of latex allergy is currently available in the United States. OBJECTIVE: Determine the accuracy of clinical assessment in predicting type I latex allergy, and compare the ability of various latex skin test preparations and in vitro assays in confirming the diagnosis of latex allergy. METHODS: Subjects were classified into "history positive," "history ambiguous," or "history negative" based on reports of clinical symptoms. Skin prick tests were performed with ammoniated latex and glove extracts. Sera were analyzed for latex-specific IgE using the Pharmacia CAP and DPC AlaSTAT assays. RESULTS: A total of 207 subjects had histories taken, skin testing, and blood drawn. Out of 49 type I latex-allergy "history positive," 42 (86%) were skin test positive, and 24 (49%) were serum positive. Fifty-nine subjects were latex allergy "history ambiguous." In this group, skin testing showed 19 (32%) positives, and latex-specific IgE were detected in 10 (17%). Out of 99 latex "history negative," 9 (9%) were skin test positive, and 11 (11%) were positive for latex-specific IgE. Out of the 61 subjects with IgE symptoms following latex exposure who were skin test positive, a positive in vitro assay was found in 32 (52%). CONCLUSIONS: Skin testing is more likely to confirm a positive latex allergy history. Use of raw ammoniated and glove skin testing preparation sources combined adds to the diagnostic sensitivity. AlaSTAT and CAP correlate well with each other and have good negative predictive value, but lack the sensitivity of skin testing. Use of AlaSTAT and CAP assays combined raises the diagnostic sensitivity as compared to using one in vitro test alone.

Shared IgE-binding sites among separated components of natural rubber latex.

BACKGROUND: IgE-mediated allergy to proteins present in natural rubber latex is a well-recognized problem. Latex contains a complex mixture of proteins ranging in molecular weight from 6 to > 200 kD. OBJECTIVE: The aim of this study was to determine whether shared allergenic sites exist on separate latex components. METHODS: Following electrophoresis, latex components at 14, 24, and 46 kD were electroeluted from SDS-polyacrylamide gels and used in ELISA inhibition and immunoblot inhibition studies of human latex-specific IgE antibodies. RESULTS: A minimum of 4 major allergenic sites (for convenience labeled A through D) were found to exist in 3 components of nonammoniated latex. Minimally, 2 are present in the 14-kD component (A, B) and 3 in the 24-kD component (A-C). The 46-kD fraction has 3 or more antigenic sites (A, C, D) but lacks one (B) that is present in both the 14- and 24-kD components. CONCLUSIONS: Four different IgE-binding moieties were detected among three latex protein components (14, 24 and 46 kD). Some of these allergenic sites were shared by two or more components. Recovery of these and others from fragmented latex components will allow identification of their amino acid composition and their availability will ultimately lead to better diagnostic and therapeutic options for patients with latex allergy.

Immunopharmacology.

Clinicians, in general, must understand the basis of immunomodulation; management principles associated with organ transplantation, autoimmune diseases, and allergic reactions; and complications of therapy. They must recognize that these patients require multidisciplinary treatment and coordination of care. Oral health care providers must recognize that immunotherapy may produce adverse effects by direct toxicity at the cellular level or indirectly, characterized by myeloimmunosuppression, and respond to the obligation to deliver quality care, competently and timely before, during, and after immunotherapy.

Latex hypersensitivity in emergency medical service providers.

BACKGROUND: Emergency medical service providers have a high degree of exposure to latex products. Patients utilizing emergency medical services can be allergic to latex products used during rescue efforts. OBJECTIVE: To determine the prevalence of latex hypersensitivity among emergency medical service providers. METHODS: Study questionnaires were distributed to a group of emergency medical service providers. Skin prick testing was performed using latex, common aeroallergens, and food extracts. Patch testing was done using latex and individual rubber additives. Serum latex-specific IgE was also measured. RESULTS: A total of 93 completed surveys were collected. Average exposure to latex in the work environment was 8.2 years. Eighty-four (90%) used latex gloves routinely at work. Of those, thirteen (14%) gave history of reaction to latex gloves. Sixty-two percent were not aware of the possibility of latex allergy in themselves or their patients. Forty-one (44%) had skin testing. Of those, four (10%) had positive prick tests for at least one of the four latex preparations used. Five had positive skin tests to avocado extract without supporting clinical history. Two had positive skin tests to banana, one with supporting clinical history for banana allergy. No food cross-reactivity with latex was demonstrated. Latex-specific serum correlated with prick skin test results. No positive reactions were noted with patch testing. CONCLUSIONS: A significant percentage of emergency medical service providers were not aware of the occupational risk of latex allergy or the potential risk in their patients. A positive prick skin test for latex was present in 4 of 41 (10%), representing one-third of those who reported symptoms from latex exposure.

A guinea pig model of hypersensitivity to allergenic fractions of natural rubber latex.

Allergy to natural rubber latex is a growing medical problem with life-threatening aspects. The aim of this study was to learn if guinea pigs could serve as a suitable model for immediate-type hypersensitivity to latex. Guinea pigs were immunized either with whole non-ammoniated latex extract, or with one of nine SDS-PAGE-separated components. Other animals were injected with electroeluted latex components localized on gel at 14, 24 and a cluster around 45 kD. Before and after immunization, sera from the animals were examined by ELISA, immunoblots, passive cutaneous anaphylaxis (PCA) and passive systemic anaphylaxis. Latex-specific antibodies were detected by ELISA and immunoblots in sera from all immunized animals. PCA assays showed that the guinea pigs had homocytotropic antibodies dilutable to 1:250. PCA was abolished when sera from animals immunized with allergens in alum were heated at 56 degrees C for 30 min indicating the antibodies were of the E isotype. Passive systemic anaphylaxis was induced in 4 of 10 guinea pigs. The results show that guinea pigs are capable of making antibodies to latex protein components that mediate dermal and systemic anaphylaxis, paralleling the spectrum of clinical and laboratory findings of humans with immediate-type clinical latex hypersensitivity.

Latex hypersensitivity: its prevalence among dental professionals.

Reports of hypersensitivity to latex are growing among oral health care workers, who have a high degree of exposure to latex products. The authors undertook a study to determine the prevalence of latex hypersensitivity among oral health care workers in a hospital dental practice. Among the 34 people who participated in the study, 12 percent had positive results in a skin prick test for latex. This suggests that the true prevalence rate of immediate hypersensitivity to latex in this group of oral health care workers is similar to that in other health care workers who use latex gloves frequently.