Unique and shared IgE epitopes of Hev b 1 and Hev b 3 in latex allergy.

Of the several latex proteins cloned and expressed, the rubber elongation factor, Hev b 1, and the closely related Hev b 3, represent two major allergens associated with latex allergy. Although both allergens demonstrated IgE binding with sera from latex allergic patients, it was not known whether these two molecules shared any epitopes. Hence, in the present study using health care workers (HCW) and spina bifida (SB) patients with latex allergy, we investigated the IgE binding epitopes in Hev b 1 and Hev b 3. Recombinant Hev b 1 and Hev b 3 were expressed in a prokaryotic expression system, while overlapping decapeptides of Hev b 1 and Hev b 3 were synthesized on derivatized cellulose membrane. Eight IgE binding epitopes for Hev b 1 and eleven for Hev b 3 were identified using sera from latex allergic patients with SB. On further analysis of synthetic peptides encompassing these epitopes, similar IgE antibody reactivity was demonstrated with three Hev b 1 epitopes b1E3, b1E5, b1E6 and two Hev b 3 epitopes; b3E10 and b3E 11. For Hev b 1, a unique IgE binding epitope was identified in the region of amino acid residues 16-25. In competitive ELISA, peptides bIE2 and bIE4 together inhibited 58% of IgE binding of Hev b 1, while b3E5 showed 22% inhibition in the IgE binding of Hev b 3. The results of the present study suggest that the understanding of linear and conformational IgE epitopes in the major latex allergens may provide better insight into the structure-function relationship of the allergens, and may lead to the development of better patient care and management strategies in latex allergy.

Latex allergen levels of injectable collagen stored in syringes with rubber plungers.

OBJECTIVES: To assess the latex allergen content of glutaraldehyde cross-linked injectable bovine collagen stored in rubber plunger syringes. METHODS: Extracts of syringe plungers and collagen solutions before and after storage in syringes with natural rubber latex plungers were tested for latex protein allergens. Thirty-nine patients known to be allergic to latex underwent skin prick testing with extracts of the latex plungers, collagen solutions before and after storage in syringes, standard latex skin test reagents, four extracts from commercially available gloves, and positive (histamine) and negative (diluent) control solutions. Thirty-one control patients not known to be latex allergic were similarly tested. RESULTS: No latex proteins were detected using in vitro immunochemical techniques. Only 1 of 39 (2.5%) latex allergic patients reacted to the syringe extract and the collagen stored in the syringe. No reactions were recorded to collagen that no contact with latex. CONCLUSIONS: The level of latex antigens in injectable collagen is very low. The low prevalence of skin test reactivity in these highly latex allergic individuals suggests that type 1 hypersensitivity reactions as a result of latex contamination would be unlikely.

Anaphylactic reaction to synthetic luteinizing hormone-releasing hormone.

Synthetic LH-RH is a polypeptide that is structurally identical to natural LH-RH. It has been used as a safe ovulation induction agent. A case is presented in which a patient had an anaphylactic reaction when treated with LH-RH by IV infusion. Positive skin testing confirmed this as an IgE-mediated reaction. This is the first reported case of such a reaction and stresses that careful precautions be taken when administering all medications.

The management of medical emergencies in otolaryngology.

We have tried to present the clinically relevant medical problems that otolaryngologists may face and to suggest management plans. Emergencies are divided by specific problems into general chemical, metabolic, and surgical categories. Space limitation allows only discussion of the most important problems but will hopefully stimulate interest in the remainder.

Latex allergy--a clinical perspective.

Latex allergy has been increasingly recognized in the past 6 years. Defined risk groups are health-care workers, spina bifida children, and possibly food allergy patients. Powdered latex gloves and latex barium enema tips are products most commonly associated with allergy. Clinically, patients present with contact urticaria, allergic rhinoconjunctivitis, asthma, and anaphylaxis. At least 15 deaths are reported to have occurred because of latex allergic reactions. Severe occupational latex allergy can result in removal of the affected individual from the workplace. This will have important cost implications. The only presently available treatment of latex allergy is avoidance.

New developments in latex allergy.

There are several new developments in studies of latex allergy. It appears that many of the allergens to latex are defense proteins that the plant uses to respond to pathogens. Rubber elongation factor, hevein preprotein, hevamine, patatin, and glucanase have been identified as allergic proteins. In addition, processing and leaching of natural rubber latex devices results in a very low allergen content. Powdered rubber gloves appear to be a major contributor to airborne latex allergens. The replacement of low allergen-containing latex gloves for high allergen-containing gloves markedly reduces the levels of latex allergens in the clinical setting. By decreasing the inhalation and contact with latex allergens, we would expect a reduction in latex sensitization in the hospital.

Scientific assay methods as the basis for glove selection.

Allergies to latex proteins and glove chemicals are increasing in the clinical practice setting. Inasmuch as latex is ubiquitous in the health environment, individuals may be exposed to latex antigens by a number of different routes, including compromised skin, mucous membranes of the respiratory and urogenital tracts, and internally during surgery. As demonstrated by numerous research articles, the key factors that appear to play a role in acquired latex hypersensitivity are chemicals used in the manufacture of products; the level of residual latex proteins, and the presence of glove powder, which binds latex protein. Currently, devices and materials containing latex are not labeled, although this may be rectified by the FDA in the near future. Until products are labeled, it is important for physicians to familiarize themselves with the routes of sensitization, variations in assay methods, and the type and amount of allergen in products in order to select the safest product for patient use and personal protection.

Latex allergy: its importance in clinical practice.

Latex has been identified as a potent and significant allergen. Atopic medical and dental personnel who regularly use latex gloves and patients with chronic latex exposure are at increased risk of latex allergy. If this allergy is unrecognized, anaphylactic shock can occur as a result of mucosal latex absorption at the time of surgery or procedure. Use of a nonlatex glove can prevent this potentially fatal event. Latex anaphylaxis also can occur from absorption through disrupted skin in occupationally exposed patients. Further prospective studies are needed to look at the significance of a positive latex skin test, particularly in the history-negative population. Only then can we define appropriate screening procedures.

Psyllium anaphylaxis.

Allergic reactions from handling psyllium have been reported since 1970. Health professionals and workers in laxative-manufacturing plants are at greatest risk. Sensitized people are at risk of life-threatening anaphylactic reactions. Two illustrative cases are presented. The first is A 39-year-old female dialysis nurse with a 3-year history of nasal and eye symptoms from exposure to psyllium. She obtained an over-the-counter psyllium bulk laxative, took it for constipation and developed flushing, tachycardia, urticaria, angioedema, laryngeal edema, and lightheadedness. An epicutaneous skin test and radioallergosorbent test for psyllium were both strongly positive. The second is a 42-year-old female nurse with a history of asthma who had allergic nasal and eye symptoms while dispensing psyllium. She received a prescription for crystallized psyllium, took it by mouth, and developed immediate flushing, tachycardia, urticaria, and angioedema. With subsequent ingestion of psyllium she had, in addition, severe wheezing, lightheadedness, and loss of consciousness. A psyllium epicutaneous skin test was strongly positive. These patient reports illustrate the risk of severe allergic reactions in sensitized people. Ingestion by sensitized people, such as from a routine postoperative and postpartum order, is potentially dangerous.

Latex sensitization: occupational versus general population prevalence rates.

BACKGROUND: Natural rubber latex (NRL) has become an important occupational health concern in recent years, particularly among health care workers. It has been suggested in some reports that the prevalence of latex sensitization among occupationally exposed groups is not different from that in the general population. METHODS: The findings of prevalence studies conducted among occupationally-exposed and general population groups were reviewed to determine whether there is evidence to support this suggestion. RESULTS: Numerous surveys of HCWs have demonstrated that the prevalence of sensitization to latex ranged in most studies from 5 to 12%; sensitization of HCWs may produce clinical effects including urticaria, rhinoconjunctivitis, occupational asthma, and potentially life-threatening anaphylactic shock. More than a decade ago, data from Finland indicated that the prevalence of latex allergy in the general population was less than 1%. Recent reports from Finland have confirmed this, with observations that 0.7-1.1% of large series of patients were NRL-allergic, while among 804 unselected patients, the prevalence of latex skin prick test (SPT) positivity was 0.12%. In contrast, other studies have suggested that from 4 to 6.4% of individuals tested were positive for serum latex-specific IgE antibodies. However, the specificity of these assays has been reported to be low. In three recent studies based on SPTs, published in 1997, the prevalence of positive reactions to latex was about 1% or less. The prevalence was 0.7% (95% CI 0.3-1.4) among 758 apprentices in Quebec, Canada; and 1.1% among more than 3,000 children tested in Finland (1.0% confirmed on latex use test). There were no first- and second-year dental students with positive latex SPTs in Ontario, Canada. CONCLUSIONS: These recent investigations provide further evidence consistent with earlier studies based on skin testing that the prevalence of latex sensitization in occupationally-unexposed groups is quite low (< 1%). The marked differences in the findings based on serological assays may relate to the nonspecificity of these assays and deserve further investigation.

Syndrome of idiopathic chronic urticaria and angioedema with thyroid autoimmunity: a study of 90 patients.

From a pool of 624 patients with idiopathic chronic urticaria and angioedema, 90 patients had evidence of associated thyroid autoimmunity (TA). Since the number expected by chance alone is 37, given that less than 6% of normal subjects have TA, the association is significant (p less than 0.01; chi-square test). Age and sex distribution was typical of patients with TA. Clinically, most patients suffered relentless and severe urticaria and/or angioedema. With the exception of thyroid function and thyroid antibody tests, other laboratory tests were not rewarding. In most cases, treatment with 1 thyroxine did not improve urticaria or angioedema, but a few patients demonstrated a dramatic response. Awareness of the association resulted in the identification of previously undiagnosed thyroid disease. The authors hypothesize that a subset of idiopathic chronic urticaria and angioedema may be an autoimmune disease.

Allergy to latex rubber.

OBJECTIVE: To summarize the clinical symptoms of latex rubber allergy and provide guidelines for the management of this allergy. DATA SOURCES: The English-language literature was searched from 1979 through 1994 manually and using MEDLINE. Conference proceedings and reference lists of relevant articles were reviewed. DATA EXTRACTION: Studies clinically relevant to latex allergy were selected. RESULTS: The most common clinical presentation of latex allergy is a nonimmunologic, irritant dermatitis of the hand. Contact dermatitis (type IV delayed hypersensitivity reactions to rubber additives) is the most common immunologic manifestation of latex rubber allergy. Type I allergic responses are less common and include contact urticaria, rhinoconjunctivitis, asthma, and anaphylaxis. Seven percent to 10% of health care workers regularly exposed to latex and 28% to 67% of children with spina bifida have a positive skin test result to latex proteins indicating increased blood levels of IgE antibody. About one third of patients with positive skin test results, however, do not yet have symptoms of latex allergy. Systemic (life-threatening) anaphylactic shock can occur intraoperatively in highly sensitive patients because of mucosal absorption of latex protein allergens from the surgeon's gloves. The present treatment for latex allergy is careful avoidance of latex materials. In addition, the use of powder-free latex gloves can eliminate airborne latex exposure and can allow health care workers with inhalant allergic reactions to return to work. CONCLUSION: Latex allergy currently affects thousands of people. These persons have IgE-mediated cutaneous, respiratory, and systemic allergic reactions. A reduction of the total protein level on latex rubber devices may prevent further sensitization and eliminate latex allergic reactions.

Treatment of inflammatory myopathy with intravenous gamma globulin.

Intravenous immunoglobulin (IVIg) is a new modality used to help treat conditions associated with immune dysregulation. The inflammatory myopathies are a group of complex diseases including dermatomyositis, polymyositis, and inclusion-body myositis. Overall evaluation of IVIg in myopathy has been hampered by difficulty in accurately diagnosing and assessing disease activity. The lack of large, well controlled, double-blind trials has precluded clear evaluation of the effectiveness of IVIg in these diseases. However, from the data presented in published reports, it appears that IVIg may be useful in the treatment of inflammatory myopathies, particularly dermatomyositis.

Asthma and anaphylactoid reactions to food additives.

Presumed allergic reactions to hidden food additives are both controversial and important. Clinical manifestations include asthma, urticaria, angioedema, and anaphylactic-anaphylactoid events. Most adverse reactions are caused by just a few additives, such as sulfites and monosodium glutamate. Diagnosis is suspected from the history and confirmed by specific challenge. The treatment is specific avoidance.

The role of infection in atopic dermatitis.

explain this tendency to develop infections. A decrease in the number and function of CD8+ suppressor/cytotoxic T cells from peripheral blood of AD patients has been reported.2 This could explain the increased incidence of cutaneous viral and fungal infections observed in these patients. Monocytes from AD patients secrete increased levels of interleukin (IL)-10 that can inhibit T cell mediated responses.3 Leukocytes from patients with AD have been found to produce decreased amounts of interferon gamma (IFN-g),4 which is required for the

Dietary aspects of adverse reactions to foods in adults.

Dietary considerations play an important role in the diagnosis, treatment and management of immunologic and nonimmunologic reactions to foods. Food diaries and trial elimination diets may prove helpful in identifying the responsible foods. Elimination diets must be monitored carefully for nutritional adequacy and should be used no longer than absolutely necessary; in some instances appropriate vitamin and mineral supplementation may be necessary. Ideally the identification of foods that provoke symptoms should be confirmed by means of double-blind challenge testing. Avoidance of some problem foods is unlikely to cause nutritional problems, but the practical and nutritional implications of allergies to staple foods such as cow's milk, eggs and wheat are far greater. Nonimmunologic adverse reactions that may mimic food allergic reactions include gastrointestinal disorders, sensitivity to food additives and psychologically based adverse reactions. There may be some degree of tolerance in metabolic disorders, which makes dietary management easier. Sensitivity to food additives necessitates careful scrutiny of food labels. In psychologic adverse reactions to foods, several foods are often involved, which increases the risk of nutritional problems.

Psyllium allergy in hospital personnel: a report on twelve patients.

We have followed 12 patients with acute symptoms on exposure to psyllium over a three-year period. All were hospital personnel with evidence of atopy. Exposure was by inhalation on dispensing psyllium powder. Symptoms which occurred within minutes of exposure included rhinitis (12/12), conjunctivitis (10/12), shortness of breath and wheezing (9/12). All patients had psyllium-specific IgE antibodies demonstrated by either positive prick-skin tests (1:100) or serum antibodies (rast). Controls had no reactivity to psyllium. Sensitivity persisted over the entire three-year period. We conclude that sensitivity to psyllium is an IgE-mediated occupational allergy in hospital personnel; that it produces significant symptoms and it is often unrecognized; and that persistance of sensitivity necessitates strict avoidance of psyllium by all routes of exposure.

Latex sensitivity in dental students and staff: a cross-sectional study.

BACKGROUND: Dental practitioners, like other health care providers who regularly use latex gloves, are at increased risk for latex sensitivity. They are also at risk for irritant or allergic contact dermatitis. OBJECTIVE: This study was carried out to determine the prevalence of latex sensitivity and possible risk factors in staff and students of a Faculty of Dentistry. METHODS: A cross-sectional study was performed by using a questionnaire and allergy skin prick testing. RESULTS: Two hundred three students and staff members completed the questionnaire. Five percent reported asthma symptoms on exposure to rubber products, 13% reported symptoms of rhinitis or conjunctivitis, and 17% reported pruritus or urticaria within minutes of exposure to rubber. Overall, 10% of 131 subjects who underwent skin prick tests had a positive response to natural rubber latex. Among the students tested, there were increasing percentages of positive skin test responses to latex with increasing years of study (0% of Year 1 and 2 students tested; 6% of Year 3; and 10% of Year 4). Positive responses were seen as early as Year 3 in students (in their second year of clinical activity and glove use). Positive skin prick test responses to latex were related to a personal history of atopy (p = 0.005), positive prick test responses to common allergens (p < 0.005), latex-attributed immediate pruritus or urticaria (p < 0.05), rhinoconjunctivitis (p < 0.001), and asthma symptoms (p < 0.001). CONCLUSION: Dental school students and faculty are at high risk for latex sensitization. This occurs as early as the second year of glove use. Overall prevalence of skin sensitization was 10% of those tested. Preventive strategies in this group merit further investigation.

Melkersson-Rosenthal syndrome: clinical, pathologic, and therapeutic considerations.

Melkersson-Rosenthal syndrome (MRS) has been described as a rare disease. Localized swelling (usually of the lips) with noncaseating epithelioid granuloma is necessary for diagnosis. We report 11 patients with biopsy-proven MRS. Mean age was 28 years (range 12-47 years). Mean duration of lesions was 4.4 years. Lip biopsy confirmed typical sarcoid-like granuloma. Five additional patients with typical symptoms are awaiting or refused lip biopsy. Clinically all patients presented with localized swelling of the lips. Treatment with clofazimine (100 mg 4 times weekly for 3-11 months) was associated with complete remission in 5/10 patients and clinical improvement in 3/10 patients with moderate constant swelling. Two patients (one severe and one moderate swelling) failed to respond to treatment. Rebiopsy in four patients confirmed improvement with disappearance or decreased granulomatous inflammation in 3/4. Complete spontaneous remission was also seen in three untreated patients. We conclude MRS is not uncommon, clofazimine may be effective treatment in moderate lesions and spontaneous remissions can occur.

Latex allergy in housekeeping personnel.

BACKGROUND: Latex allergy has been well described in healthcare workers and children with spina bifida. Cost effective measures to avoid latex allergic reactions are possible in these recognized risk groups. OBJECTIVE: To study the prevalence of latex allergy among hospital housekeepers regularly exposed to latex gloves. METHODS: Fifty members of the housekeeping staff at a Toronto teaching hospital were screened by questionnaire for latex allergy. Patients with possible atopy or symptoms suggestive of latex allergy (20) were skin tested with latex (Bencard Laboratories) eight common allergens and histamine control. RESULTS: Four of 20 tested had a positive latex prick skin test representing an 8% prevalence overall within this group, and a 20% prevalence among atopic housekeepers. Based on an expected 1% prevalence in the general population, this was statistically significant (P < .005). Latex-positive patients had extensive exposure to high protein-unlined latex gloves. Positive patients had a similar yet completely unique immunoblot pattern of IgE binding. All four positive patients had unrecognized latex allergic symptoms (hand dermatitis, rhinoconjunctivitis). One housekeeper experienced itchiness of her face, angioedema, and lightheadedness immediately after inflating a latex balloon. CONCLUSIONS: The 8% prevalence of a positive latex skin test in regularly exposed hospital housekeepers is similar to that observed among healthcare workers suggesting this is a new risk group.