[Erythroderma secondary to latex-producing plants (Synadenium grantii)]

The Euphorbiaceae family are plants that have in common latex production. There are over 8000 species. They have worldwide distribution. We can find trees, shrubs or herbs. Many important species belong to this family and they are used in our country for industrial and medical purposes. There are also ornamental plants with attractive appearance that stimulate children curiosity, intake or manipulation. In the National Poison Center consultations for plants represent a small number (0.2%) of the total accidents in children, however they can be serious. We report the case of a 4 years old girl who manipulated and swallowed part of an Euphorbiaceae family plant (Synadenium grantii).

Occupational allergy to latex among loom tuners in a textile factory

BACKGROUND

Occupational allergy to latex is generally reported from occupational groups such as health care workers; however, few reports derive from other occupational settings.

METHODS

Two male subjects working as loom tuners in a textile manufacturing plant developed severe allergic reactions during the cutting and weaving of elastic bands, initially not suspected to contain latex constituents. Clinical evaluation and lung function tests were supplemented by skin prick testing, specific IgE evaluation and basophil activation assays with extracted elastic bands.

RESULTS

Both workers presented with rhinitis, episodes of tight chest and itchy eyes. Initial spirometry was normal with no significant reversibility; however, a histamine challenge test was positive in one worker. Skin prick testing to a battery of common inhalant allergens was negative; however, raised IgE levels were detected to latex using ImmunoCAP. On further testing, the specific IgE response was directed mainly to the major latex allergens rHev b 5, rHev b 6.01, rHev b 6.02 and nHev b 13. Basophils of the two workers, but not the unaffected control subjects, were strongly activated by extracts of the elastic and the cutting dust material.

CONCLUSIONS

Workers are at high risk of becoming sensitised to latex allergens when exposed to excessive dust produced by loom tuning machines. Latex sensitisation should therefore be considered in workers developing unexplained work-related allergic reactions (including asthma) associated with unlabelled materials in the textile industry.

Advances in development of hypoallergenic latex immunotherapy

PURPOSE OF REVIEW

The characterization of clinically relevant latex allergens and the production of recombinant allergens is now well advanced, but this knowledge needs to be translated into new strategies for the safe and effective specific treatment of latex allergic diseases including asthma and anaphylaxis.

RECENT FINDINGS

The current status of latex allergy is discussed indicating a changing demographic paradigm. A new wave of latex allergy is emerging outside the healthcare setting with the widespread use of latex products. An increased prevalence in developing countries is also reported. Limited studies on current specific immunotherapy for latex allergy are reviewed, confirming the feasibility but demonstrating an unacceptable risk of adverse events. The characterization of latex allergens and the identification of B and T-cell epitopes point to rational strategies for the generation of hypoallergenic preparations for specific immunotherapy. Results to date for latex allergens are reviewed, including recombinant, chemical modification and synthetic peptide approaches. Candidate hypoallergenic preparations for targeting sensitization to the major allergens Hev b 1, Hev b 3, Hev b 5 and Hev b 6.01 have been identified. Further investigations of optimal regimens for the delivery of specific immunotherapy to induce regulatory T-cell function are warranted.

SUMMARY

The findings point to the selection of suitable hypoallergenic preparations for clinical trials of effective and safe latex allergy immunotherapy.

Latex allergy: a challenge for anaesthetists

First reported in 1979, anaesthetists now encounter more and more patients with latex allergy. Several risk groups prone to develop this allergy have been identified. A thorough preoperative interview is necessary to detect high-risk patients. For them, the perioperative period is very dangerous because of the many possibilities of contact with latex-containing materials. There is no cure for latex allergy. Absolute avoidance of contact with latex is the only safe way to treat those who belong to a risk group or who are already allergic. The diagnosis of latex allergy must be kept in mind in every case of perioperative anaphylaxis, even if the patient does not belong to a risk group. In the future, desensitization will probably be useful in helping patients with latex allergy.

New insights on latex allergy diagnosis and treatment

Because of widespread latex manufacturing in the last decades, exposure to latex has become ever greater, as has the incidence of latex allergy among the general population as well as the high-risk groups. Clinical manifestations range from local reactions (edema, itching, erythema, and papulae), rhino-conjunctivitis, asthma, pharyngeal edema, to severe systemic reactions such as anaphylactic shock (from parenteral exposure especially during medical examinations or surgical procedures). Diagnosis is formulated on the basis of the personal history and an accurate allergological evaluation. Patients usually have a history of food intolerance or adverse reactions during medical or surgical procedures, which are believed to be the result of anesthetics or other drugs. In vivo tests are prick and patch tests and challenge tests. Challenge tests (nasal, conjunctival, bronchial, intravaginal, sublingual, oral, and cutaneous tests) are important for confirming the diagnosis, for evaluating a patient's response to the different kinds of latex exposure, and for verifying the effects of desensitizing treatments on the various organs involved in latex allergy. The most important in vitro test is the specific anti-natural rubber latex IgE assay. The only effective resolution to the latex allergy problem seems to be desensitization. The criteria of effectiveness are the capability to use latex items, to undergo medical examinations (even invasive), and to remain in an environment where latex particles can be inhaled (such as surgical departments), without symptoms. The first attempts were performed by subcutaneous administration of latex, but this protocol seems to be delicate to perform because of the side effects. Two different alternative methods (percutaneous and sublingual) were successfully performed and proved to be safer and more effective, even though further studies on a larger group of patients are needed.

Allergen cross-reactivity between proteins of the latex from Hevea brasiliensis, seeds and pollen of Ricinus communis, and pollen of Mercurialis annua, members of the Euphorbiaceae family

Allergen cross-reactions among three strongly sensitizing Euphorbiaceae species, i.e., the rubber tree (Hevea brasiliensis), castor bean (Ricinus communis), and the Mediterranean weed Mercurialis annua were studied in Finnish patients (n = 25) allergic to natural rubber latex (NRL), but with no known exposure to castor bean or M. annua, and French patients allergic to castor bean (n = 26) or to M. annua (n = 9), but not to NRL. In immunoglobulin E (IgE)-immunoblotting, 28% of NRL-allergic patient sera recognized castor bean seed and 48% reacted to castor bean pollen proteins. Likewise, 35% of the NRL-allergic patient sera bound to M. annua pollen allergens. Nineteen percent of castor bean-allergic patients showed IgE to NRL and 8% to M. annua proteins. Sera from patients allergic to M. annua reacted in 44% to NRL, in 56% to castor bean seed, and in 78% to castor bean pollen proteins. In immunoblotting, castor bean seed extract inhibited the binding of NRL-reactive IgE to 20 kDa, 30 kDa of NRL, and 55 kDa of proteins; NRL extract, in turn, inhibited the binding of castor bean-reactive IgE to 14, 21-22, 29, and 32-34 kDa of castor bean proteins. In ELISA inhibition, NRL extract inhibited 33% of the binding of M. annua--reactive IgE of pooled sera to M. annua pollen. In conclusion, allergen cross-reactivity in vitro was observed among three botanically related Euphorbiaceae members, H. brasiliensis, R. communis, and M. annua, but the molecular specificity of the observed cross-reactions as well as their clinical significance remains to be elucidated. Allergen cross-reactivity should be taken into account in diagnostic work.