Latex allergies

Sept. 1, 1999
Hand care is essential for health-care professionals. Any abrasion, cut, or minor trauma can compromise the integrity of the skin, creating a portal of entry for a variety of organisms. Wearing latex gloves is the most common and effective means of protecting health-care personnel and their patients when there is potential for contacting blood, saliva, or mucous membranes.

Some health-care providers are at high risk for allergic reaction to natural rubber latex.

Karen Gomolka

Hand care is essential for health-care professionals. Any abrasion, cut, or minor trauma can compromise the integrity of the skin, creating a portal of entry for a variety of organisms. Wearing latex gloves is the most common and effective means of protecting health-care personnel and their patients when there is potential for contacting blood, saliva, or mucous membranes.

However, reactions to natural rubber latex (NRL) can and do occur, especially among those who wear latex gloves routinely. People with a genetic predisposition and a high exposure to latex products are at increased risk. Additional risk factors include those with a history of surgery, especially during childhood; spina bifida patients; and patients with other disorders necessitating repeated urinary catheterization. An allergy to NRL also may be more likely to develop in people with food allergies.

Three types of common latex reactions, ranked in order of severity, are: (1) Irritant dermatitis, (2) Type IV hypersensitivity, and (3) Type 1 hypersensitivity.

Irritant dermatitis

Many health-care workers (perhaps half of the individuals who routinely wear gloves) experience irritant dermatitis, a nonimmunologic process that damages the superficial layers of the skin. It is caused by contact with a substance that physically or chemically challenges the skin. Affected people typically notice that the epidermis (top layer of the skin) becomes reddened, dry, irritated, and even cracked in severe cases. All symptoms appear to stop at the boundary of the glove cuff with the skin.

Frequent handwashing with soaps or antimicrobial antiseptics, failure to completely rinse and dry, irritation from the cornstarch powder in gloves, and excessive perspiration on hands while wearing gloves can initiate and aggravate this condition.

To reverse irritant dermatitis and protect against subsequent reactions, health-care providers should initially focus on ascertaining the potential causes of the problem. The first thing to check is the daily handwashing routine. Other possible solutions may include selecting a different brand of latex gloves containing less or no powder, using a different lot of the same brand of gloves, or changing glove brands.

Type IV hypersensitivity

Type IV reactions are limited to areas of contact and do not involve the entire body. Contact with chemicals - such as those used in the processing of latex - produces an immune response that is followed 48-72 hours later by a red, itchy rash. In its most severe form, vesicles or blisters appear. This type of reaction can take up to four days to heal with necrosis, scabbing, and sloughing of affected epithelium. This type of reactivity can become a chronic problem.

Type IV latex hypersensitivity has been found to be the most common NRL allergy. It is caused by the chemicals added to crude, milky latex during the manufacture of latex products. Numerous scientific reports have documented the presence of over 200 chemical additives in latex products.

Because a delayed allergy or an irritant dermatitis may be caused by one or a combination of the many chemicals or procedures utilized in health care, identification of the causative agent(s) requires patch testing. Chemicals such as glutaraldehyde and acrylates readily permeate most glove materials, and reactions often are attributed to the gloves rather than to the true irritant or allergen.

Type 1 allergic reaction

A Type 1 reaction is directed against latex protein components. It is an immunologial response usually occurring two to three minutes after contact with the latex allergens via tissues (skin) or mucous membranes. Itching at the contact site is followed within minutes by a pale, elevated, irregular whelt or "wheal," followed by a rash or "urticaria." There will be a possible return to normal appearance within approximately 30 minutes. However, a spectrum of reactivity for Type 1 hypersensitivity ranges from a generalized rash to conjunctivitis, rhinitis, bronchospasm, and hypotension. In extreme cases, anaphylaxis occurs, which, if left untreated, could lead to death.

With latex-sensitive health-care workers, the Type 1 response is manifested soon after donning latex gloves with itching and a burning sensation. After the gloves are removed, hives and localized edema may appear.

A more severe manifestation of Type 1 hypersensitivity can develop in some individuals who are challenged with airborne allergens. NRL proteins can adhere to cornstarch powder particles during the product`s manufacturing process. The proteins subsequently can remain suspended in the air, bound to powder, for prolonged periods. The presence of excessive powder on latex gloves - along with frequent removal of gloves from boxes during the day - can cause substantial particle aerolization. As a result, respiratory and conjunctival exposure of sensitized persons to NRL proteins can stimulate more systemic anaphylactic symptoms - coughing, wheezing, shortness of breath, and/or respiratory distress.

Diagnosis of Type 1 allergy reaction should include an occupational and clinical history. Currently in the U.S. there is no standardized, commercially available skin-prick test (SPT) for latex allergy. The only decisive way to ascertain allergenicity to NRL is to be appropriately tested by an allergist.

At this time, there is no specific cure. for latex allergy. Prevention, avoidance, and symptomatic treatment are the only options.

This resource was reprinted with the permission of OSAP. OSAP is a nonprofit organization providing information and education on dental infection control and office safety. For more information, please call (800) 298-6727.

Latex allergy: summary & recommendations

* Health-care providers should be familiar with the different types of latex hypersensitivities, immediate and delayed, and the risks they pose to them and their patients.

* Handwashing after glove use may reduce future development of latex hypersensitivity in dental health-care workers.

* All people with immediate-type allergy symptoms ? eye and nasal symptoms, cough, wheezing, decreased blood pressure, dizziness ? developing within minutes of latex exposure should avoid any contact with latex products.

* Latex allergens in the ambient air can cause respiratory and/or anaphylactic symptoms in a susceptible person.

* Inadvertent exposure to latex may cause reactions that should be treated aggressively, especially when anaphylaxis is involved.

* Oral health-care providers with hand dermatitis are advised to use hypoallergenic gloves that are free of the offending chemicals (the term OhypoallergenicO no longer will be employed on any latex-containing gloves).

* Patients may be at risk for development of reactions to latex gloves, rubber dams, prophy cups, or orthodontic elastics during a dental procedure.

* It is advisable that all patients with spina bifida have latex-free dental and medical procedures. This is recommended because of the high incidence of life-threatening reactions to latex products in those patients.

* People with immediate-type symptoms are advised to wear an allergy-alert label and to carry medication to be used in an emergency situation, as explained by the appropriate medical personnel.

* Latex allergies should be documented in medical/dental records and given similar importance as other drug- or local anesthetic-related hypersensitivities.

* Identification of latex-containing devices in oral health-care settings and substitution with latex-free dental products is vital.

* Some product labels might not yet clearly state their latex contents; therefore, extra caution is warranted.

* Latex-free kits and gloves should be available in all dental offices/clinics for high-risk people.