PREVALENCE OF AND RISK FACTORS FOR LATEX SENSITIZATION IN PATIENTS WITH SPINA BIFIDA

Manifestation of intraoperative anaphylactic shock along with latex allergy:a pediatric case report

Natural rubber latex (NRL) allergy is one of the most important causes of severe anaphylaxis during medical intervention. We report a pediatric case of latex allergy with multiple surgical histories. A 12-year-old girl developed anaphylactic shock during the pyeloplasty for ureteropelvic junction restenosis. Latex gloves or medications used during the surgery were suspected to be the cause of anaphylactic shock. We diagnosed her latex allergy on the basis of the results that serum latex-specific IgE, skin prick tests of extract from NRL gloves and recombinant Hev b 6.02 solution were positive. Basophil activation test of NRL gloves was also positive, supporting the diagnosis of immediate allergic reactions caused by NRL. It was speculated that a history of multiple surgeries in infancy became a trigger of sensitization to latex in this patient. Reoperation after the diagnosis of NRL allergy was carried out in a latex-free environment and completed without any allergic symptoms. It would be necessary to perform the pre-screening of latex allergy to prevent the onset of latex allergy especially in the patients with multiple surgical histories. J. Med. Invest. 65:292-295, August, 2018.

Diagnostic Value of Three Different Latex Extracts

The diagnosis of latex allergy is made on clinical history, but a confirmatory skin prick test (SPT) or a serological assay based on a commercial latex extract is always recommendable. Different raw materials can be used in the preparation of commercial latex extracts. Such extracts can consequently show both different qualitative profiles and a different diagnostic potential. Therefore, the selection of a proper latex extract is essential for in vitro and in vivo diagnosis of latex allergy. In the present study three different latex extracts, prepared from different raw materials (ammoniated -AL-, serum -SL-, or rubber particles -RPE- latex), are compared by in vitro techniques using sera from twenty patients with latex allergy. SDS-PAGE technique was used to compare the antigenic profile of the three latex extracts. Subsequently, their allergenic profiles were evaluated by immunoblotting technique using the individual sera from the twenty latex allergic patients. The diagnostic potential of the three latex extracts was also evaluated using direct Radio-Allergo-Sorbent Test (RAST) as well as skin prick tests (SPTs). In order to establish the more appropriate latex extract in a perspective of in vivo diagnosis of latex sensitization, the same latex extracts were subsequently compared by an in vivo SPT involving ten of the above subjects. The SDS-PAGE profiles of the three latex extracts examined were quite different. SL extract showed numerous bands comprised between 10–100 kDa. RPE extract was characterized by two intense bands at 14 and 20 kDa while AL extract showed the poorer antigenic composition. Analogously, immunoblotting analysis evidenced a different profile in relation to both different patients and extracts. For only two out of the twenty sera, direct RAST results showed a same positive class in relation to the different latex extracts used. SPT with SL extract showed, in respect to the other extracts (AL, RPE), a significantly higher wheal. This study showed that SL extract is able to express the best in vitro and in vivo diagnostic potential. Thus, its use should be preferred for the diagnosis of patients affected by latex allergy.

Prenatal latex sensitization in patients with spina bifida: a pilot study

OBJECT

Patients with spina bifida are particularly vulnerable to developing immunoglobulin E (IgE)-mediated latex sensitization. Even though many risk factors leading to latex allergy in these patients have been described, it is still unclear whether the increased prevalence of latex sensitization is disease associated or due to the procedures used to treat spina bifida. The aim of this study was to assess prenatal latex sensitization in patients with spina bifida by examining IgE levels in umbilical cord blood.

METHODS

Patients with spina bifida and matched healthy infants were recruited from the University Medical Center Hamburg-Eppendorf and Children's Hospital Altona. Latex-specific and total IgE were assessed in umbilical cord blood using ImmunoCAP testing to evaluate the degree of prenatal latex sensitization.

RESULTS

Twenty-two subjects, 10 with spina bifida and 12 healthy individuals, were included. Subjects were selected after matching for sex, gestational age, weight, parental allergy profile, number of prenatal examinations, and utilization of latex tools during pregnancy (propensity score estimates, p = 0.36). In patients with spina bifida, latex-specific and total IgE levels were significantly higher than those in healthy individuals (p = 0.001). After normalization to total IgE, latex-specific IgE levels were higher, yet not significantly increased (p = 0.085).

CONCLUSIONS

Perinatally, there is a significant augmentation of total and latex-specific IgE in patients with spina bifida. After correcting for total IgE, latex-specific IgE was increased, yet not significantly higher than in matched, healthy controls. This pilot study gives novel insights in the immunological reactions related to spina bifida. The increased latex-specific IgE levels could possibly be associated with the occurrence of a latex allergy in the future.

Prevalence of latex allergy in spina bifida patients in Singapore

Background

Latex allergy and its clinical presentation are rising in prevalence across the globe, especially amongst patients with spina bifida (SB). While studies have been well-established in Europe and America, data from Asia are limited.

Objective

The aim of this study is to investigate the scenario in Singapore.

Methods

35 subjects with SB, aged 5 to 32 years answered a questionnaire and underwent skin prick test (SPT) using a latex solution, 3 common house dust mites and 3 commonly cross-reacting food allergens (banana, kiwi and avocado). We also noted the relation between latex sensitization with atopy and doctor-diagnosed allergy. The prevalence of cross-reactivity with fruits was also studied.

Results

Sensitization to latex (i.e. a positive SPT) was found in 16 (46%, 95% confidence interval 29%-63%) of the subjects. Only 5 (31%) of the subjects who were sensitized to latex had clinical manifestations. Atopy (i.e. positive SPT to house dust mites) was present in 23 (66%) of the subjects and 13 (57%) of them was also sensitized to latex. There was a positive trend between latex sensitization and atopy (81.2% vs. 52.6%, p = 0.076), as well as latex sensitization with those having both atopy and doctor-diagnosed allergy (i.e. asthma, allergic rhinitis, eczema, drug allergy) (93.8% vs. 63.2%, p = 0.032). Only 6 (38%) subjects had allergy to the food allergens tested.

Conclusion

Almost half of the SB patients in Singapore are sensitized to latex. This number is comparable to that in Europe and America. Positive trend between latex sensitization and those with both atopy and doctor-diagnosed allergy (p = 0.032) is suggestive of a possible cause-effect relationship.

Perioperative Latex Allergy

The prevalence of latex allergy varies greatly depending on the population studied and the methods used to detect sensitization. Subjects considered to be at high risk for latex allergy are rubber industry workers, children with spina bifida and urological abnormalities, children undergoing multiple surgical procedures and with urinary catheterization, health care workers and people with food allergy (latex fruit syndrome). In this paper we report a review of latex proteins, the symptoms of latex allergy, diagnosis and management in subjects with latex allergy.

Allergen specific nasal challenge to latex in children with latex allergy: clinical and immunological evaluation

There are no data concerning the significance of allergen specific nasal challenge to latex (ASNCL) in the pediatric population and the effect of mometasone furoate nasal spray (MFNS), topic corticosteroid exerting a potent anti-inflammatory activity in children with latex allergic rhinitis. The aims of this study are: to investigate the clinical and immune pathological effects of ASNCL in children with latex allergy; to study the effects of MFNS pre-medication on the clinical and immune pathological effects of ASNCL in children with latex allergy. Thirteen children: 6 male and 7 female, mean (SD) age 9.6 (2.9) years, with latex allergy and seven children: 3 male and 4 female, mean (SD) age 9.9 (3.8) years, without latex allergy underwent ASNCL. Nasal symptoms were recorded, nasal lavage fluid was collected to measure tryptase, eosinophil cationic protein (ECP), interleukin-5, interferon-gamma levels, and spirometric test was performed for each patient without or with premedication with MFNS. ASNCL induced a clinical allergic response and increased tryptase levels only in children with latex allergy. No serious adverse events occurred after ASNCL. MFNS premedication reduced both tryptase and ECP levels only in children with latex allergy. ASNCL is a simple, reliable and useful tool to make or confirm the diagnosis of nasal symptoms due to latex; it allows us to study both clinical symptoms and local immunological changes. MFNS premedication before an ASNCL may prevent some immunological responses induced by ASNCL without clinical allergic modifications.

Myelomeningocele: neglected aspects

The commonest cause of neurogenic bladder in children is myelomeningocele. Survival of children is much improved in the Western world, but by 35 years old, about 50% will have died. In adults, the commonest causes of death are lung and heart diseases. All physical aspects deteriorate with age, especially in those with thoracic lesions. Those who walk in childhood have a 20-50% chance of becoming wheelchair dependent as adults. Immobility, poor respiratory reserve, obesity, latex allergy and worsening kyphoscoliosis contribute to the increased risks of surgery. It is essential that safe and manageable urine drainage is established in childhood: the bladder never improves with time, and surgical reconstruction becomes progressively more difficult. Independence in adult life will only be possible with intense preparation in childhood. Children must be allowed to join in with family chores and events. Education, both academic and practical, must be encouraged. Skills such as driving, shopping and birth control must be taught. However, even with the best support, less than 40% will have gainful employment. Children who are continent and have lesions below L2 are likely to have normal sexual function. Sexual activity in adolescents, especially in those with hydrocephalus, is limited (but not absent). However, by adult life, about two thirds will have established a regular partnership. All females and those males who are naturally potent are likely to be fertile. There is a high risk of neural tube defects in their offspring unless the female partner takes prophylactic folic acid for 3 months before pregnancy and for first trimester.

Latex-induced anaphylactic reaction in a child with spina bifida

Allergy to natural rubber latex presents a unique challenge in the emergency department. Latex allergy in children is most commonly identified in patients who have undergone multiple operations for neural tube defects or genitourinary anomalies. We report a life-threatening anaphylactic reaction to latex in a patient with spina bifida even with latex-free precautions.

[Latex allergy]

Latex allergy has become an increasing cause of morbility in the last few years and is now recognized as an international health problem. The prevalence of latex sensitization among the general population is less than 1 %. The groups at highest risk include healthcare workers, rubber industry workers, patients with a history of multiple surgical procedures, particularly children with spina bifida and urogenital abnormalities, atopic individuals, and patients with certain fruit allergies (especially kiwi, avocado, chestnut and banana). The molecular and immunological characteristics of several natural latex allergens have been identified. Symptoms range from contact urticaria to anaphylaxis. Diagnosis is based on clinical history and is confirmed by skin prick tests. Measurement of serum specific IgE to latex can also be useful. The best treatment is latex avoidance and substitution by other materials. However, because latex products are ubiquitous in medical and nonmedical devices of daily use, a latex-free environment is not easy to achieve. In some patients, immunotherapy could be an alternative.

Toxicological and immunological aspects of occupational latex allergy

Latex allergy continues to be an important occupational health problem as latex products are used increasingly worldwide, particularly in healthcare. Although there are few epidemiological studies on the incidence of latex allergy, there has been an increase in the number of case reports over the last 10 years and, based on skin-prick tests, estimates of prevalence of latex allergy in healthcare workers range from 2% to 17%. The allergic health effects arise either from the latex proteins, generally causing a type I immediate hypersensitivity reaction, or from the chemicals added to latex during processing, causing a type IV delayed hypersensitivity reaction. Clinical manifestations of latex allergy depend on the route of exposure and occur by direct contact either with skin or mucosa, or by inhalation. The diagnosis of latex allergy is based on the history, skin tests, serological tests and challenge tests. Thirteen latex allergens have been identified and isolated so far from natural rubber latex. They differ in their potential to elicit immunological responses in individuals allergic to latex and thus have been designated as major or minor allergens. In latex gloves, cornstarch powder used as a donning agent carries latex proteins, thereby increasing inhalational and mucosal exposure to latex proteins. There also appears to be a positive correlation between protein content and allergenicity of gloves. The use of powder-free, low-protein gloves is effective in reducing symptoms and markers of sensitisation. Alternatives to latex gloves, such as nitrile or vinyl gloves are available but may be inferior in respect to manual dexterity and biological impermeability.

Latex allergy in children with urological malformation and chronic renal failure

PURPOSE

Children with spina bifida, bladder exstrophy and anorectal anomalies are at risk for latex allergy. Severe intraoperative anaphylaxis in a boy treated with kidney transplantation prompted this study to evaluate the prevalence of latex allergy in a cohort of children with chronic renal failure (CRF).

MATERIALS AND METHODS

Between 1996 and 2002, 57 boys and 28 girls were investigated at a median age of 10.5 years (range 1.3 to 22.9). Urological malformations were the underlying cause of CRF in 33 patients (39%). Of the patients 39 were on conservative treatment, 20 were on dialysis and 26 had a functioning renal graft. Latex reaction was assessed by a careful history, specific serum latex IgE and skin prick test.

RESULTS

A total of 19 patients (22%) showed latex reaction, of whom 8 had allergy (clinical symptoms included severe intraoperative anaphylaxis in 1) and 11 had sensitivity (positive IgE or prick test without symptoms). Of these 19 patients 11 had urological malformations. The number of surgical procedures, young age at operation and atopy were significant risk factors. When operations were analyzed separately, ie urological vs nonurological surgery, only urological surgery was significantly associated with latex reaction. A significant correlation was also found between the overall number of operations and latex radioallergosorbent class.

CONCLUSIONS

All children with CRF who undergo early and multiple urological surgery are at high risk for latex reaction. Primary latex prevention, ie the routine use of latex-free gloves, tubes and catheters, should be implemented in all children with complex urological malformations.

Role of cross-allergies to latex in clinical routine of anesthesia

STUDY OBJECTIVE

To determine the applicability and reliability of a screening questionnaire to detect patients at high-risk of latex allergy; to assess the importance of other allergies such as profilin allergies (pollinosis) for presence of latex sensitization; and to determine the clinical effectiveness of preemptive avoidance of latex exposure in high-risk patients.

DESIGN

Prospective, clinical trial.

SETTING

Operative theater of a university hospital.

PATIENTS

95 adult patients.

INTERVENTIONS

Patients were preoperatively screened and classified for present latex allergy (high-risk and low-risk group) according to a specially designed screening questionnaire. Anesthesia and surgery in the high-risk group were performed strictly avoiding latex-containing materials. The low-risk group (other allergies including pollinosis) received routine treatment, without latex-avoidance. Effects of latex avoidance or exposure were evaluated by measuring specific IgE titers perioperatively.

MEASUREMENTS AND MAIN RESULTS

According to the questionnaire, 45 patients at high risk were defined. Validity of classification of high-risk patients is supported by significantly higher total IgE and latex and grass profilin specific IgE compared to the low-risk group. There were no significant differences in other profilin-specific IgEs. In one case of severe anaphylactic reaction a drop of latex-specific IgE during surgery could be observed.

CONCLUSION

The questionnaire allowed the identification of most patients at high risk for latex allergy. In isolated pollinosis no changes in any specific IgE levels were detectable. Strict avoidance of perioperative latex exposure in high-risk patients increases safety during anesthesia and surgery.

Cross-reactivity between gutta-percha and natural rubber latex: assumptions vs. reality

BACKGROUND

Immunological cross-reactivity between gutta-percha and natural rubber latex, or NRL, has not been demonstrated clearly despite recent concerns and several suspected cases reported in the literature.

METHODS

The authors analyzed aqueous extracts of commercial gutta-percha points and raw gutta-percha samples for cross-reactivity to NRL by radioallergosorbent test, or RAST, inhibition; immunoblot inhibition; direct enzyme-linked immunosorbent assay, or ELISA; and ELISA inhibition using sera from NRL-allergic people as the source of anti-NRL immunoglobulin E, or IgE, antibodies. To confirm in vitro results, the authors conducted skin prick testing, or SPT, on a patient with type I NRL allergy using aqueous extracts from raw gutta-percha, ammoniated gutta-percha and gutta-percha points.

RESULTS

Aqueous extracts from commercial gutta-percha points did not cross-react to NRL in RAST inhibition or immunoblot inhibition, ELISA or ELISA inhibition assays. However, three of 13 sera from subjects with type I NRL allergy exhibited IgE binding to raw gutta-percha extracts in direct ELISA. Moreover, in ELISA inhibition, the binding of IgE to raw gutta-percha extracts was inhibited in a dose-dependent manner by raw NRL and vice versa. SPT results from a subject with type I NRL allergy were positive for NRL and raw gutta-percha extracts but negative for gutta-percha point extracts.

CONCLUSIONS

The authors found no detectable cross-reactivity between NRL and commercial gutta-percha points. However, their ELISA and SPT results demonstrated that some allergenic cross-reactivity exists between raw gutta-percha and raw NRL.

CLINICAL IMPLICATIONS

Gutta-percha alone is not likely to induce symptoms in patients with type I NRL allergy. However, other materials used in obturating root canals may be irritating and potentially allergenic in patients with pre-existing allergies.

[Latex allergy in patients with spina bifida: prevention and treatment]

Latex allergy has become a health problem of growing interest due to the severe clinical manifestations it may produce. Previous reports indicate a prevalence of latex allergy in patients with spina bifida (SB) ranging between 10% and 73%. From the initial surgical repair of the myelomeningocele, children with SB are submitted to multiple surgeries due to the neurologic, orthopedic and urologic problems they may present. Consequently, these children are exposed to several latex-containing products during their multiple interventions. Several reports indicate that latex allergy in SB children is related to age, and especially to the number of operations that they are given, and perhaps to an unknown genetic predisposition. Accordingly, latex allergy manifestations can be prevented. In this connection, we have elaborated at our hospital protocols for the management of the three clinical situations in which these patients can present. These measures include: (1) To avoid using latex-containing products since the birth of children with SB. (2) In children already operated of myelomeningocele but without evidence of latex allergy, to prevent the use of latex materials during their successive admissions to hospital and during further surgeries. And (3) In children known to have developed latex allergy, to dispose of especial nursing measures and of a latex-free operating room. The preventive measures that have been started at our Hospital are easy to carry out, do not suppose a high economic cost, and are not uncomfortable for the hospital's staff.

[Peculiarities of latex allergy and preventive measures in the pediatric age group]

Latex allergy can be considered a problem of public health in at-risk populations. Although the figures on prevalence vary, approximately 1 % of the general population is sensitized to latex. To date, two determining factors for latex sensitization have been identified: an atopic predisposition and the number of operations. Among atopic patients or those at-risk for allergy, the prevalence of latex sensitization is between 3 and 20 times higher than that among the general population. Nevertheless, the effect of this factor seems to be modulatory and the determining factor seems to be the number of operations that children have undergone; the critical number is 5-6 interventions, after which the probability of sensitization increases considerably.All children who have undergone multiple operations should be considered as being at-risk. Children with spina bifida are especially at-risk. The reasons for this are still a matter of debate: the disease itself has been postulated as a specific risk factor, although other, possible associated factors could be determinant in triggering latex sensitization (the presence of a ventricular-peritoneal shunt, age at which surgery was performed, type of operation, etc.). Children with spina bifida and latex allergy show considerable differences in type of allergic sensitization; these differences seem to result from the different route of sensitization and could explain the variations observed in the clinical manifestations between children and adults: children become sensitized mainly by direct contact between latex particles and blood vessels and open mucosae while in adults the process takes place transcutaneously or by inhalation of aerosol particles. Consequently, the most frequent manifestation in children is urticaria while contact dermatitis and respiratory symptoms predominate in adults. Studies performed with immunoblotting have confirmed that children have IgE that almost constantly recognize low molecular weight latex proteins (14, 15 and 27 Kd) while this finding is less frequent in adults.The preventive measures in the pediatric population focus on avoidance of latex, especially in hospitals. Today, latex is ubiquitous, making complete avoidance difficult. When necessary, and whenever a latex-free environment cannot be guaranteed, presurgical medication can be used, although its utility is debatable. Although further studies are required, specific immunotherapy is one therapeutic possibility that may in future be used in children with latex allergy.

Specific monoclonal antibodies and human immunoglobulin E show that Hev b 5 is an abundant allergen in high protein powdered latex gloves

BACKGROUND

Hev b 5 is a major latex allergen recognized predominantly by latex-allergic health care workers (HCWs). Recombinant Hev b 5 (rHev b 5) was previously expressed as a fusion protein with maltose binding protein (MBP), itself an immunogenic molecule; therefore non-fusion rHev b 5 is desirable. Moreover, standardized immunological assays for the detection of Hev b 5 are currently lacking and may have important implications for both allergen avoidance and diagnosis in latex allergy.

OBJECTIVES

To generate and use Hev b 5-specific mAbs to determine the relative abundance of Hev b 5 in different latex extracts, correlating this with the IgE reactivity of latex-allergic HCWs and to produce non-fusion rHev b 5.

METHODS

For the production of mAbs, mice were immunized with rHev b 5/MBP fusion protein and mAbs selected with rHev b 5/MBP but not MBP reactivity. The mAb reactivity was compared with polyclonal IgE from latex-allergic HCWs using direct and inhibition ELISA and immunoblot assays. Recombinant Hev b 5 was expressed and purified in the pPROEX-HTa bacterial expression system.

RESULTS

Four Hev b 5-specific mAbs were produced. Immunoblotting and ELISA using the mAbs indicate abundant Hev b 5 in high protein powdered latex glove extracts as compared with crude latex sap extracts. High quality surgical gloves with no detectable protein have no detectable Hev b 5. Inhibition ELISAs using serum IgE from latex-allergic HCWs and Hev b 5-specific mAbs gave strong correlation. Non-fusion recombinant Hev b 5 was successfully expressed and purified, showing reactivity with both the Hev b 5-specific mAbs and serum IgE of latex-allergic HCWs.

CONCLUSION

Hev b 5-specific mAbs and human IgE from latex-allergic HCWs demonstrate the greater content of Hev b 5 in high protein powdered glove extracts. This may explain the observed higher frequency of sensitization to this allergen in HCWs.

Risk factors for latex sensitization in children with spina bifida

BACKGROUND

Children with spina bifida represent the major risk group for latex sensitization.

PURPOSE

To determine the prevalence of latex sensitization in these children and to identify risk factors.

MATERIAL AND METHODS

We studied 57 patients with spina bifida. The mean age was 5.6 years and the male/female ratio was 0.8/1. In all patients a questionnaire, skin prick test (SPT) with latex (UCB-Stallergènes, Lofarma and ALK-Abelló), common aeroallergens and fruits (UCB-Stallergènes) and serum determination of total IgE (AlaSTAT) were performed.

RESULTS

The prevalence of latex sensitization was 30 %; only two sensitized children (12 %) had symptoms after exposure. Risk factors for latex sensitization were age >/= 5 years (p = 0.008; OR = 6.0; 95 % CI = 1.7-22.1), having at least four previous surgical interventions (p < 0.0001; OR = 18.5; 95 % CI = 3.6-94.8), having undergone surgery in the first 3 months of life (p = 0.008; OR = 5.4; 95 % CI = 0.7-29.2) and total serum IgE >/= 44 IU/ml (p = 0.03; OR = 3.8; 95 %CI = 1.1-13.1). Multiple logistic regression analysis showed that only a history of four or more surgical interventions (p < 0.0001; OR = 26.3; 95 %CI = 2.9-234.2) and total serum IgE >/= 44 IU/ml (p = 0.02; OR = 8.6; 95 % CI = 1.4-53.4) were independently associated with latex sensitization. Sex, family and personal allergic history, hydrocephalus with ventriculoperitoneal shunt, cystourethrograms, intermittent bladder catheterization and atopy were not related to latex sensitization.

CONCLUSIONS

In children with spina bifida, significant and independent risk factors identified for latex sensitization were multiple interventions and higher levels of total serum IgE. A prospective study will clarify the clinical evolution of assymptomatic children sensitized to latex.

The effect of polymethyl methacrylate on latex-free surgical gloves

In the current medical environment of increased awareness about latex sensitivity, more patients are presenting with known latex allergy. One such patient presented to us for total knee arthroplasty. During this procedure, we noticed holes in our latex-free surgical gloves when polymethyl methacrylate (PMMA) was being handled. Through subsequent testing of different brands of latex-free surgical gloves with various brands of bone-cement, we found that Allergard latex-free surgical gloves are destroyed by contact with PMMA. Biogel Neotech and Duraprene latex-free gloves show no such destruction. These results indicate that Allergard gloves should not be used in procedures in which bone-cement is employed. Biogel Neotech and Duraprene latex-free gloves are an acceptable alternative.

Latex allergy in children on home mechanical ventilation

STUDY OBJECTIVE

Determining the incidence of latex allergy in children receiving home mechanical ventilation.

BACKGROUND

The prevalence of latex allergy in the general population ranges from 0.1 to 1.0%. However, in patients with spina bifida and other chronic medical conditions associated with repeated exposure to latex, the prevalence may be as high as 60%. Children receiving home mechanical ventilation are frequently exposed to latex products. Therefore, we hypothesized that these children would be at increased risk for latex allergy.

DESIGN

Fifty-seven children receiving home mechanical ventilation (31 boys, 26 girls; mean [+/- SD] age, 7.8+/-6.6 years; range, 0.3 to 23.2 years) were enrolled. A radioallergosorbent test (RAST) for latex was administered and serum IgE levels were obtained in all patients.

RESULTS

Seventeen patients (29.8%) were found to have a positive RAST for latex. Patients with latex allergy had required mechanical ventilation for an average of 6.1+/-4.1 years vs. 5.5+/-5.4 years (p = 0.69; not significant) in those without latex allergy. Eleven of 17 patients (64.7%) had elevated serum IgE levels in the group with latex allergy vs only 14 of 40 patients (35.0%) in the group with a negative latex RAST (p = 0.04; odds ratio, 3.4).

CONCLUSION

We conclude that there is a high incidence of latex allergy in children requiring home mechanical ventilation. We speculate that screening all children receiving home mechanical ventilation may lead to the identification of patients with previously undiagnosed latex allergy and the prevention of untoward reactions from exposure to latex.

Natural rubber latex: glove use, sensitization, and airborne and latent dust concentrations at a Denver hospital

Exposure to natural rubber latex may cause immediate hypersensitivity reactions. Published latex sensitization prevalence rates range from 2.9% to 22% among health care workers, and from 0.12% to about 20% of occupationally unexposed populations. In this study, self-administered questionnaires addressed job and personal characteristics, glove use, and symptoms in two groups of hospital workers: those who regularly used latex gloves and those who did not. Serum was tested for latex-specific immunoglobulin E. Air, surface, and air-filter dust samples for natural rubber latex were collected. The prevalence of latex sensitization was 6.3% in the non-users and 6.1% in the latex glove users (P = 0.9); 81.3% of sensitized workers were atopic compared with 59.5% of non-sensitized workers (P < 0.05). Reporting of work-related hand dermatitis was more common in the latex glove users (23.4%) than in the non-users (4.9%), as were rhino-conjunctivitis (16.3% and 7.9%, respectively, [P < 0.01]), and hand urticaria (9.9% and 2.1%, respectively, [P < 0.01]). There was no significant difference in work-related symptoms between the sensitized and non-sensitized workers. Environmental concentrations of latex were higher in the work areas of the non-sensitized workers, but higher in the clinical than in the non-clinical areas. Occupational latex glove use was not a risk factor for sensitization.