Accidental rupture of membranes and neonatal infection after labor induction with silicone or latex balloon catheters: A retrospective cohort study

OBJECTIVE(S)

Accidental rupture of membranes (acROM), an insertion-related complication of the balloon catheter for labor induction, may prolong the duration of ruptured membranes. Prolonged rupture of membranes is associated with an increased risk of intra-uterine infection with possibly neonatal infection as result. Little is known about safety profiles of different catheters regarding the occurrence of these complications. This study compares the incidence of neonatal early-onset sepsis (EOS) and acROM in women receiving either silicone or latex balloon catheters.

STUDY DESIGN

A retrospective cohort study was performed including 2200 women (silicone balloon catheter, n = 1100 vs. latex balloon catheter, n = 1100). The primary outcomes were the incidence of acROM, and suspected and proven neonatal EOS. Secondary outcomes were: prolonged rupture of membranes, intrapartum fever, pre- or postnatal neonatal exposure to antibiotics, and perinatal outcomes. A subgroup analysis was performed between women with and without acROM.

RESULTS

No statistically significant difference with regard to suspected or proven EOS was seen between the silicone and latex groups. The acROM rate was significantly higher in the silicone group compared to the latex group (2.9 % and 0.3 %, p < 0.01). Prolonged rupture of membranes was significantly more common in the silicone group compared to the latex group (5.0 % and 2.4 %, p < 0.01), as was the use of intrapartum antibiotics (12.7 % and 9.6 %, p = 0.02). Neonates were significantly more often exposed to pre- or postnatal antibiotics in the silicone group compared to the latex group (17.6 % and 13.6 %, p = 0.01). Subgroup analysis showed significantly more suspected and proven neonatal EOS when catheter-insertion was complicated with acROM (11.4 % and 20.0 %), compared to cases without acROM (3.8 % and 2.5 %), irrespective of the type of catheter used.

CONCLUSION(S)

The use of silicone balloon catheters for labor induction results in higher rates of acROM, prolonged rupture of membranes and use of intrapartum antibiotics, compared to latex balloon catheters. No statistically significant differences were found in the occurrence of suspected or proven neonatal EOS, however neonates from the silicone group were more often exposed to pre- or postnatal antibiotics. When acROM occurs, irrespective of type of catheter used, suspected and proven neonatal EOS was seen more often.

Evaluation of Latex Immunoturbidimetric Assay Thresholds and HIT in Cardiothoracic Surgery

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is a common differential diagnosis in cardiothoracic surgery. The latex immunoturbidimetric assay (LIA) is an enhanced immunoassay that has recently been introduced for the detection of total HIT immunoglobulin and retains a higher specificity of 95% compared to the enzyme-linked immunosorbent assay.

OBJECTIVES

To investigate if a semiquantitative relationship exists between increasing LIA levels beyond the current positivity threshold and its correlation to positive serotonin release assay results in cardiothoracic surgery.

METHODS

This was a multicenter, observational cohort of cardiothoracic surgery patients initiated on anticoagulation with heparin-based products. To conduct sensitivity and specificity analysis of LIA values, HIT positive was defined as a LIA value ≥1 unit/mL and HIT negative was defined as a LIA level <1 unit/mL. A receiver operating characteristic (ROC) analysis was utilized to evaluate the predictive performance of the LIA.

RESULTS

At manufactures' cutoffs of ≥1.0 unit/mL, LIA sensitivity and specificity was 93.8% and 22%, respectively, yielding a false positive rate of 78%. At a higher cutoff of 4.5 units/mL, LIA sensitivity and specificity was 75% and 71%, respectively, yielding a false positive rate of 29% and an area under the ROC curve of 0.75 (P = .01; 95% confidence interval: 0.621-0.889). Bivalirudin was initiated in 84.6% of false positive LIA results.

CONCLUSION

This study suggests that the diagnostic accuracy of the LIA can be optimized by increasing the LIA positivity threshold. Proposing a higher LIA cutoff, may mitigate unwarranted anticoagulation and bleeding outcomes.

Combinations of rapid immunoassays for a speedy diagnosis of heparin-induced thrombocytopenia

BACKGROUND

Early recognition and treatment of heparin-induced thrombocytopenia (HIT) are key to prevent severe complications.

OBJECTIVE

To assess the diagnostic performance of rapid immunoassays (IA) in detecting anti-PF4/heparin-antibodies.

METHODS

Diagnostic performances of lateral-flow IA (LFIA; STic Expert HIT) and latex IA (LIA; HemosIL HIT-Ab) were analyzed in pilot (n = 74) and derivation cohorts (n = 267). Two novel algorithms based on the combination of HIT clinical probability with sequentially performed LIA and chemiluminescent IA (CLIA; HemosIL AcuStar-HIT-IgG) were compared with published rapid diagnostic algorithms: the "Lausanne algorithm" sequentially combining CLIA and particle-gel IA (PaGIA) and the "Hamilton algorithm" based on simultaneously performed LIA and CLIA.

RESULTS

LFIA missed 6/30 HIT. The sensitivity and specificity of LIA were 90.9% and 93.5%. The Lausanne algorithm correctly predicted HIT in 19/267 (7.1%), excluded it in 240/267 (89.9%), leaving 8/267 (3%) cases unsolved. The algorithm sequentially combining CLIA and LIA predicted HIT in 19/267 (7.1%) with 1/19 wrong prediction, excluded it in 236/267 (88.4%), leaving 11/267 (4.1%) cases unsolved. The algorithm employing LIA as a first assay predicted HIT in 22/267 (8.2%), excluded it in 235/267 (88%), leaving 9/267 (3.4%) cases unsolved. Finally, the Hamilton algorithm correctly predicted HIT in 10/267 (3.7%), excluded it in 229/267 (85.7%), leaving 28/267 (10.5%) cases unsolved.

CONCLUSION

LFIA cannot be used to exclude or predict HIT when using frozen plasma. A Bayesian approach sequentially employing two rapid immunoassays for anti-PF4/heparin antibodies is most effective for the accurate diagnosis of HIT. Based on retrospective data, the combination LIA/CLIA is a candidate for a prospective validation.

Thrombin- and plasmin-like and platelet-aggregation-inducing activities of Plumeria alba L. latex: Action of cysteine protease

ETHNOPHARMACOLOGICAL RELEVANCE

In folk medicine, parts of Plumeria alba L. are used for the treatment of many diseases, with its latex being used for curing skin diseases and promoting wound healing.

AIM OF THE STUDY

This study aimed to study the role of P. alba L. latex in hemostasis and platelet aggregation.

MATERIALS AND METHODS

The latex of P. alba L. was processed to remove waxes and enrich protein content, and the final extract was named Plumeria alba L. natant latex (PaNL). PaNL was analyzed for protease activity against casein. The type of protease in PaNL was identified by using protease inhibitors such as E-64, phenylmethylsulfonyl fluoride, ethylenediaminetetraacetic acid, and pepstatin A. Human fibrinogen, fibrin, and collagen types I and IV were subjected to hydrolysis with different concentrations of PaNL. The thrombin-like activity of PaNL was determined by analyzing its fibrinogen-clotting and procoagulant activities. The role of PaNL in platelet aggregation was also investigated. Its hemorrhagic and edema-inducing activities were evaluated in a mouse model. Phytochemical compounds were identified by gas chromatography-mass spectroscopy.

RESULTS

The findings of casein/gelatin zymography confirmed that PaNL possesses protease activity. The results of the protease inhibition study indicated the presence of a cysteine-type protease(s) in PaNL. PaNL hydrolyzed the subunits of fibrinogen, fibrin, and collagen types I and IV. Its fibrin-degradation activity indicated that PaNL possesses plasmin-like activity. PaNL induced clotting of citrated human plasma within 3 min of incubation in the absence of CaCl_2, indicating the presence of thrombin-like activity, which was further confirmed by the results of the fibrinogen-clotting assay. PaNL induced platelet aggregation in the absence of agonists. There was no hemolytic activity. Mice injected with PaNL did not show edema/ hemorrhagic activity.

CONCLUSION

PaNL possesses procoagulant, fibrino(geno)lytic, thrombin- and plasmin-like activities and induces platelet aggregation, which could explain its usage for wound treatment in folk medicine.

Enhanced Internalization of Indian Ayurvedic Swarna Bhasma (Gold Nanopowder) for Effective Interaction with Human Cells

In the ancient traditional Indian Ayurvedic system of natural healing, gold nanoparticles (Swarna Bhasma, gold ash) have been used for its therapeutic benefits as far back as 2500 B.C. Ayurvedic medicinal preparations are complex mixtures that include many plant-derived products and metals. Bhasmas date as far back as the 8th century and are made by samskaras (processings), such as shodhana (purification and potentiation), jarana (roasting), and marana (incineration, trituration) in the presence of plant products, including juices and concoctions. Previous studies characterized the physical properties of gold ash, and the mechanisms of its entry into human cells, but only preliminary data exist on its toxicity. Before using nanoparticles for therapeutic application, it is extremely important to study their toxicity and cellular internalization. In the present study, various imaging techniques were used to investigate Swarna Bhasma's (gold nanopowder) toxicity in both cancerous and noncancerous cells (HeLa and HFF-1) and to characterize its spectral properties. The results showed that gold ash particles had no impact on the cellular viability of both HeLa and HFF-1 cells, even at high concentrations or long incubation times. Moreover, it was found that the internalization level of Swarna Bhasma to cells may be improved by mechanical breaking of the large aggregates into smaller agglomerates. Hyperspectral images revealed that after breaking, the small agglomerates have different spectral properties in cells, compared to the original aggregates, suggesting that size of particles is instrumental for the subcellular interaction with human cells.

EFFECTS OF TOPICAL TREATMENT WITH EUPHORBIA TIRUCALLI LATEX ON THE SURVIVAL AND INTESTINAL ADHESIONS IN RATS WITH EXPERIMENTAL PERITONITIS

BACKGROUND

The use of plants of the family Euphorbiaceae, particularly Euphorbia tirucalli (avelós) has been popularly widespread for treating a variety of diseases of infectious, tumoral, and inflammatory.

AIM

To demonstrated antimicrobial and immunomodulatory effects of these extracts, evaluating the effect of a topical treatment with an aqueous solution of avelós latex on the survival and on intestinal adhesions in rats with experimental peritonitis.

METHODS

Peritonitis was induced in 24 Wistar rats, that were randomized into four groups of six as follows: (1) Control group (n=6), no treatment; (2) Antibiotic group (n=6), treatment with a single intramuscular dose of antibiotic Unasyn; (3) Saline group (n=6), the abdominal cavity was washed with 0.9% saline; and (4) E.tirucalli group (n=6), the abdominal cavity was washed with E. tirucalli at a concentration of 12 mg/ml. The animals that died were necropsied, and the time of death was recorded. The survivors were killed on postoperative day 11, and necropsy was subsequently performed for evaluation of the intestinal adhesions.

RESULTS

Significant differences were observed in the control and antibiotic groups (p<0.01) with respect to the survival hours when compared with the saline and E. tirucalli groups. There was no significant difference (p>0.05) in the survival of animals in the saline andE. tirucalli groups; however, one animal died in the saline group. Necropsy of the animals in the saline and E. tirucalligroups showed strong adhesions resistant to manipulation, between the intestinal loops and abdominal wall. The remaining groups did not show any adhesions.

CONCLUSIONS

Topical treatment with E. tirucalli latex stimulated an increased formation of intestinal adhesions and prevented the death of all animals with peritonitis.

Rethinking cumulative exposure in epidemiology, again

The use of cumulative exposure, the product of intensity and duration, has enjoyed great popularity in epidemiology of chronic diseases despite numerous known caveats in its interpretation. We briefly review the history of use of cumulative exposure in epidemiology and propose an alternative method for relating time-integrated exposures to health risks. We argue, as others before us have, that cumulative exposure metrics obscures the interplay of exposure intensity and duration. We propose to use a computationally simple alternative in which duration and intensity of exposure are modelled as a main effect and their interaction, cumulative exposure, only be added if there is evidence of deviation from this additive model. We also consider the Lubin-Caporaso model of interplay of exposure intensity and duration. The impact of measurement error in intensity on model selection was also examined. The value of this conceptualization is demonstrated using a simulation study and further illustrated in the context of respiratory health and occupational exposure to latex dust. We demonstrate why cumulative exposure has been so popular because the cumulative exposure metric per se gives a robust answer to the existence of an association, regardless of the underlying true mechanism of disease. Treating cumulative exposure as the interaction of main effects of exposure duration and intensity enables epidemiologists to derive more information about mechanism of disease then fitting cumulative exposure metric by itself, and without the need to collect additional data. We propose that the practice of fitting duration, intensity and cumulative exposure separately to epidemiologic data should lead to conceptualization of cumulative exposure as interaction of main effects of duration and intensity of exposure.

[Predisposition to latex allergy undetected on preoperative evaluation: a case report]

A 70-year-old man was scheduled to undergo laparoscopic total gastrectomy for stomach cancer. He had no history of atopy, fruit allergies, or frequent exposure to natural rubber. Preoperative latex-specific IgE antibodies were negative. Anesthesia was induced, and the surgery was started uneventfully. Soon after the surgeon had begun to manipulate the intestine, the blood pressure suddenly dropped to 27/21 mmHg. Facial flushing was also observed. Anaphylactic shock caused by latex was strongly suspected, and surgery was immediately halted. The surgical gloves were changed to latex-free ones, and adrenaline was administered. The blood pressure was gradually normalized within 30 min, and the facial flushing mostly disappeared. Postoperative laboratory examination revealed that serum tryptase had increased to 34.4 microg l-1, 40 minutes after the onset of anaphylaxis, and decreased to 19.4 microg l-1, 24 hours than later. Latex-specific IgE antibodies and a prick test with latex were both positive. Consequently, the diagnosis of latex-induced anaphylactic reaction was confirmed. Because even detailed questioning and examination does not always identify such a predisposition, avoiding contactwith latex products is more rational exhaustively checking every preoperative patient for latex allergy

[Dental materials can cause oral allergic reactions]

A large number of materials used in the diagnosis, treatment and prevention of dental, periodontal and oral mucosal diseases may induce acute or chronic reactions in the oral cavity including allergic reactions. Clinically, it may be difficult to discriminate oral mucosal changes caused by dental materials from changes related to oral mucosal diseases. Diagnosis and management of allergic reactions in the oral mucosa may therefore be a major challenge. The purpose of this paper is to draw attention to commonly used dental materials, which can trigger typical, but also atypical, symptoms and clinical signs of an allergic reaction.

[Research into sensitization and allergies to latex: results after 10 years of the use of powder-free latex gloves]

OBJECTIVE

To compare the prevalence of sensitization and allergy to natural rubber latex amongst Erasmus Medical Centre (MC) operating theatre employees before and 10 years after the introduction of powder-free latex gloves.

DESIGN

Descriptive study.

METHOD

Employees working permanently in the operating theatre were evaluated in 1998 (n = 163) and in 2009 (n = 178) for sensitization and allergies to natural latex by means of questionnaires, serological analyses and skin testing. The prevalence of sensitization and allergies within these 2 groups was then established and compared.

RESULTS

The two groups were comparable in terms of gender, smoking habits, job classification, work-related symptoms and the number of individuals who had atopy. In 2009, the prevalence of sensitization to latex was statistically significantly lower than in 1998 (4.5 vs. 14.1%). Allergy to latex was also established a statistically significantly fewer number of times in 2009 than in 1998 (2.8 vs. 9.8%). This same trend could be observed in the subgroup that participated both years (n = 49). Individuals with an atopic constitution had a statistically significant higher risk of developing hypersensitivity to natural latex; the risk of developing an allergy to latex was also higher, but not significantly.

CONCLUSION

After the study in 1998, the introduction of sterile, powder-free latex gloves very likely led to a decline in the prevalence of sensitization and allergy to natural latex in 2009.

Risk factors associated with asthma phenotypes in dental healthcare workers

BACKGROUND

Exposure in the dental environment can increase the risk of respiratory disease in dental healthcare workers (HCWs). This study investigated the prevalence of asthma phenotypes in dental HCWs and associated risk factors.

METHODS

A cross-sectional study of 454 dental HCWs in five dental institutions in South Africa was conducted. A self-administered questionnaire elicited the health and employment history of subjects. Sera was analyzed for atopic status and latex sensitization. Pre- and post-bronchodilator spirometry was performed.

RESULTS

The prevalence of atopic asthma was 6.9%, non-atopic asthma 5.9% and work-exacerbated asthma (WEA) 4.0%. Atopy and work-related ocular-nasal symptoms were strong predictors of WEA (OR: 3.4; 95% CI: 1.07-10.8; OR: 6.7, 95% CI: 2.4-19.1), respectively. Regular use of personal protective equipment (PPE) was associated with a protective affect (OR: 0.23, 95% CI: 0.1-0.7) among non-atopic asthmatics, while glove use and respiratory protection was protective among atopic asthmatics (OR: 0.39, 95% CI: 0.17-0.89).

CONCLUSION

Identification of risk factors associated with specific asthma phenotypes in dental HCWs can be used to focus preventive strategies for asthmatics.

Interest of exhaled biomarkers in occupational asthma to latex: a case report

New methods for exploring pulmonary inflammation might be useful: measurements of exhaled nitric oxide (NO) and hydrogen peroxide (H(2)O(2)) in exhaled breath condensate (EBC). The authors describe the application and utility of these methods in a case report of pediatric nurse presenting an occupational asthma to latex. Despite compliance with avoidance measures, respiratory discomfort had worsened during work. Classical tests (spirometry, monitoring of peak expiratory flow) were not contributing to objectify the discomfort. Exhaled NO and H(2)O(2) in EBC increased immediately after work periods, compared with rest periods. Application of these new methods, at the same time, in workplace appears useful in the objective demonstration of a temporal relation between work and respiratory problems. The results allowed the occupational physician to transfer the patient to a new work station more appropriate for her respiratory health status.

Latex allergy in dental students: a cross-sectional study

BACKGROUND

Latex allergy is a major occupational health problem in health care workers who regularly use latex gloves. Dentists are one of the high risk groups for latex allergy and sensitization as it is generally found that healthcare workers (HCW) have 3 times greater prevalence of latex allergy. There are very few studies of latex allergy in HCW in Thailand.

OBJECTIVE

To study the prevalence of latex-related symptoms, latex-sensitization and possible risk factors in dental students.

MATERIAL AND METHOD

A cross-sectional study was performed on all dental students of the Faculty of Dentistry, Chulalongkorn University, during Dec 2007 to May 2008, using questionnaires and skin prick tests (SPT), using 3 latex extracts prepared from Proglove, Doctor Plus gloves and a commercial latex allergen (Stallergenes, France). SPT was done only in those who were willing and signed informed consents.

RESULTS

There were 617 completed questionnaires (87.3%). The mean age of the volunteers was 20.9 +/- 1.7 years with 29.3% male and 70.7% female. The prevalence of latex glove-related symptoms was 5.0%. These symptoms were all local, cutaneous symptoms, ranging from hand pruritus (64.5%), hand eczema (19.4%) and contact urticaria (16.1%). Eight subjects (1.3%) reported pruritus or urticaria on exposure to other rubber products while 12 subjects (1.9%) reported reactions to some fruits. The risk factors for latex-glove allergy were personal history of allergic diseases (atopic dermatitis, urticaria, pruritus and rubber allergy), duration of using gloves more than 18 hours per week, more than 3 pairs of gloves used per day and timing of glove exposure. The 4th to 6th year students were observed significantly more prevalence of symptoms than the 1st to 3rd year students (OR, 3.69; 95% CI, 1.73-7.87; p = 0.0003). SPT for 3 extracts of latex was done in 247 cases (40.0%); overall latex sensitization rate was 14.2%. The commercial extract had higher incidence of latex sensitization compared to the 2 gloves extract. The 1st year students had the lowest percentage of latex sensitization (3.2%) and positive skin test was significantly found in the 2nd year students (20.8%; OR, 6.46; 95% CI, 1.87-47.98; p = 0.04).

CONCLUSION

The prevalence of latex allergy in dental students is 5% and the signs and symptoms were local cutaneous reaction; pruritus, eczema and contact urticaria. The latex sensitization rate in dental students was14.2%, which is higher than the general population. The possible risk factors included personal history of allergic diseases, duration and frequency of exposure. Therefore, primary prevention of the occupational latex allergy should be carefully considered especially concerning high risk factors.

Latex anaphylaxis caused by a Swan-Ganz catheter

A 78-year-old woman visited the division of cardiovascular disease in our hospital. She underwent a cardiac catheter examination, and a Swan-Ganz catheter was inserted. Several minutes later, she developed anaphylactic shock. She had no past history of latex allergy, but did have a banana allergy. Skin prick tests showed a positive reaction to an extract of latex gloves and an extract of the balloon of a Swan-Ganz catheter. Anaphylactic shock caused by the latex balloon of a Swan-Ganz catheter was diagnosed. It is necessary to pay attention to not only latex allergy but also fruit allergies with a cross-reactivity to latex.

Effects of latex avoidance on latex sensitization, atopy and allergic diseases in patients with spina bifida

BACKGROUND

Ten years ago, avoidance measures such as the performance of latex-free operations were implemented in children with spina bifida. Since then, latex sensitization and latex allergy have decreased in this high-risk group.

OBJECTIVE

To study the effect of primary latex-free prophylaxis on the prevalence of allergic diseases and atopy as a marker for sensitization spreading in children with spina bifida.

METHODS

One hundred and twenty children with spina bifida born after the introduction of latex-free prophylaxis and operated on under latex-free conditions ('current group') were examined for latex sensitization, latex allergy, sensitization to aero- and food allergens and allergic diseases. Results were compared to a 'historic' (not latex-free operated) group of children with spina bifida and comparable age (n = 87) and to a recent sample of children from the general population (n = 12,403).

RESULTS

In comparison with the 'historic group', latex sensitization (55% vs 5%, P < 0.001) and latex allergy (37% vs 0.8%, P < 0.001) were significantly reduced in the 'current group'. Furthermore, a significant reduction could be demonstrated for sensitization to aeroallergens (41.4% vs 20.8%, P = 0.001) and for allergic diseases (35% vs 15%, P = 0.001). The prevalence for atopy, sensitization to aero-/foodallergens and for allergic diseases in children of the 'current group' was similar to those in children of the weighted population sample.

CONCLUSIONS

Latex avoidance in children with spina bifida prevents latex sensitization and latex allergy. Additionally, it also seems to prevent sensitization to other allergens and allergic diseases which might be explained by the prevention of sensitization spreading.

[A case of anaphylactic shock by multiple causes]

We experienced anaphylactic shock after introduction of the general anesthesia twice in the same patient. After the first incidence of anaphylactic shock, we judged that the allergen was a latex. For the second time we planned the latex free environment, but the anaphylactic shock occurred again. As a result of the investigation, it turned out that the allergens were due to latex and sevoflurane. After the first incidence, it was necessary to retrieve the antigen from all the agents used. When we encounter the anaphylactic shock, it is necessary to examine all the medicines, and should have two or more suspectible medicines in mind.

Perioperative anaphylaxis

The incidence of immune-mediated anaphylaxis during anesthesia ranges from 1 in 10,000 to 1 in 20,000. Neuromuscular blocking agents are most frequently incriminated, followed by latex and antibiotics, although any drug or substance used may be a culprit. Diagnosis relies on tryptase measurements at the time of the reaction and skin tests, specific immunoglobulin E, or basophil activation assays. Treatment consists of rapid volume expansion and epinephrine administration titrated to symptom severity.

Suspected allergy to local anaesthetics: follow-up in 135 cases

BACKGROUND

Local anaesthetics (LA) are generally considered safe with respect to allergy. However, various clinical reactions steadily occur. Even though most reactions are manifestations of reflexes to perceptive stimuli, uncertainty often remains regarding a possible allergic mechanism. This uncertainty later leads to an avoidance of local anaesthesia and unnecessarily painful interventions, resource-consuming general anaesthesia or even the risk of re-exposure to other yet unidentified allergens. In the present study, follow-up procedures at an allergy clinic were analysed to examine the frequency of identified causative agents and pathogenetic mechanisms and evaluate the strength of the diagnostic conclusions.

METHOD

The medical records of 135 cases with alleged allergic reactions to LA were reviewed. Diagnoses were based on case histories, skin tests, subcutaneous challenge tests and in vitro IgE analyses.

RESULTS

Two events (1.5%) were diagnosed as hypersensitivity to LA, articaine-adrenaline and tetracaine-adrenaline, respectively. Ten reactions (7%) were diagnosed as IgE-mediated allergy to other substances including chlorhexidine, latex, triamcinolone and possibly hexaminolevulinate. As challenge testing was not consistently performed with the culprit LA compound, follow-ups were short of definitely refuting hypersensitivity in 61% of the cases. The reported clinical manifestations were in general diagnostically unspecific, but itch and generalised urticaria were most frequent in test-positive cases.

CONCLUSION

Reactions during local anaesthesia are rarely found to be an IgE-mediated LA allergy. Whenever the clinical picture is compatible with allergy, other allergens should also be tested.

[Allergic reaction during anesthesia: two case reports]

We experienced two cases of serious and potentially life-threatening allergic reactions. The first patient was a 28-year-old male patient scheduled for surgery for cerebral arteriovenous malformations and another patient was a 66-year-old male patient scheduled for hepatic resection. After uneventful anesthetic induction, anesthesia was maintained with sevoflurane, air and oxygen. Both patients developed allergic reactions characterized by cardiovascular failure during anesthesia. Resuscitative treatment included rapid fluid infusion, administration of adrenaline and steroid. Both patients were successfully resuscitated without any lasting sequelae. The causative agent in one of these cases was probably a prophylactically used antibiotic, while that of the other case was a reaction to latex. Both patients showed elevated histamine and tryptase concentrations in blood samples. Recently, the incidence of allergic reactions to antibiotics and latex during anesthesia is increasing. Anesthesiologists should, therefore, be aware of the possibility of allergic reactions to all drugs and substances, especially to latex, during the perioperative period.

Latex-induced occupational asthma: time trend in incidence and relationship with hospital glove policies

BACKGROUND

Natural rubber latex (NRL) has become as a major cause of occupational asthma (OA) in workers using NRL gloves. Few population-based studies have assessed the impact of changes in the patterns of glove usage on the incidence of NRL-induced OA.

OBJECTIVE

To characterize the time trends in incident cases of NRL-induced OA in Belgium and examine whether incidence rates were related to the types of gloves used in hospitals.

METHODS

Incident cases of NRL-induced OA were identified through a retrospective review of all claims submitted to the Workers' Compensation Board up to December 2004. Based on the results of diagnostic procedures, the diagnosis of NRL-induced OA was categorized as definite, probable, unlikely, or indeterminate. The patterns of glove usage were characterized through a questionnaire survey of Belgian hospitals.

RESULTS

A total of 298 claims for NRL-induced OA were identified, including 127 subjects with definite OA and 68 with probable OA. Categorized by the year of asthma onset, the incident cases of definite and probable NRL-induced OA markedly decreased from 1999 onwards. The use of powdered NRL gloves fell from 80.9% in 1989 to 17.9% in 2004. Powdered NRL gloves were predominantly substituted with NRL-free gloves, especially in the case of non-sterile procedures.

CONCLUSION

These national compensation-based data confirm that a persistent decline in the incidence of NRL-induced OA has occurred since late 1990s. This downward trend has temporally been associated with a decreasing usage of powdered NRL, further supporting a beneficial role of changes in glove policies.

Allergenic compounds on the inner and outer surfaces of natural latex gloves: MALDI mass spectrometry and imaging of proteinous allergens

Natural latex gloves are the cause of a severe health problem to an increasing number of healthcare workers or patients due to the presence of protein allergens as Hevein or Rubber Elongation Factor (REF). One of the most challenging problems is the in situ localization of theses allergens in, e.g. gloves, to estimate the allergenic potential of the latex material. A sample preparation protocol applying a binary matrix-assisted laser desorption/ionization(MALDI) matrix containing alpha-cyano-4-hydroxy cinnamic acid (CHCA) and 2,5-dihydroxy benzoic acid (DHB) on trifluoro acetic acid (TFA) etched latex glove surfaces allowed the direct determination (exact molecular weight) of Hevein, REF and a truncated form of REF (tREF) within nine different brands of natural latex gloves by means of MALDI-TOF-MS in the linear mode. MALDI mass spectrometry demonstrated that Hevein, tREF and REF were present on the inner surfaces (in direct contact with the skin) of many, but not all, investigated gloves without any prior extraction procedure. Additionally, different isoforms of the allergen Hevein were detected (exhibiting ragged C-termini). tREF and REF could always be detected beside each other, but were not observed on every latex glove sample, which contained Hevein. It was also demonstrated that there is a significant difference in terms of proteins and polymers between inner and outer surfaces of gloves, which helps to explain the different allergenic potential of these.MALDI imaging allowed for the first time the unambiguous localization of all three allergens in parallel and showed that Hevein was present on 36% of the investigated area of a latex glove with a certain localization, whereupon, tREF and REF were only found on 25% of the investigated material.

[Consensus Document. Update on latex exposure and use of gloves in Italian health care settings]

This consensus document was prepared by an Italian working group including occupational health professionals involved for many years in the management of glove- and latex-related problems in health care settings. The aim of this document was to address the most significant technical, epidemiological, clinical, environmental and prevention problems related to the use of gloves and latex. The group's recommendations are based on scientific evidence and practical experience but they cannot be considered as final. These topics need to be periodically revised. The following points should be taken into account: glove quality seems to have improved considerably but the information on glove features provided by the manufacturers is often still inaccurate or incomplete; the regulations in force provide that the manufacturers perform tests to supply evidence for the quality of the products but they do not indicate which analytical method should be used and they do not require that the results be reported in the technical data sheets. Thus the manufacturers have only to declare that their products are "in accordance with the rules"; therefore, purchasers should require the manufacturing companies to supply detailed information and verify their reliability. Moreover, the rules should be adapted to higher quality standards; occupational physicians must be involved for the correct choice and purchase of protective gloves; the use of gloves (in particular latex gloves) and latex devices in health care settings should be based on specific criteria: procedures must be available stating which kind of gloves are suitable for specific tasks. When exposure to latex cannot be avoided it is necessary to choose products that have good biocompatibility (e.g., powder free-gloves with low allergen content); once and for all latex powdered gloves should no longer be commercially available! labels for latex devices (including gloves) should report the extractable latex allergen content. Limit values for extractable latex allergens should be established; the use of synthetic rubber gloves should be encouraged since some materials (e.g., neoprene and nitrile rubber) appear to have physical properties and protective efficacy similar to latex, plus good biocompatibility; more studies should be promoted to verify the protective efficacy of new synthetic materials; health care workers should be informed about the advisability and usefulness of using materials other than latex; health care services should not cause additional risks but rather highlight the advantages for workers and patients if the use of latex gloves and devices is minimized.

[Anaphylactic reaction to latex during spinal anesthesia: a case report]

A 46-year-old man, with a history of atopic dermatitis and bronchial asthma, underwent surgery for an inguinal hernia. Forty-three minutes subsequent to spinal anesthesia, the patient complained suddenly of dyspnea with wheezing. Blood pressure decreased and skin eruption was observed on his chest. Postoperative laboratory tests revealed high IgE concentration, and a skin test confirmed an allergy to latex. The patient's allergic reaction was easily overlooked because of his history of bronchial asthma and the possibility that the hypotension was caused by the high spinal anesthesia. Latex allergy should be considered in any suspicious case presenting with these symptoms during surgery. After recovery, a skin test should be used to confirm the allergy to avoid repeated allergic episodes.

Anaphylaxis-induced acute ST-segment elevation myocardial ischemia treated with primary percutaneous coronary intervention: report of two cases

Acute coronary syndromes have been described as potential complications of any type of anaphylactic reaction. The real pathogenic mechanism inducing acute myocardial ischemia in the setting of anaphylaxis is not yet completely understood. Some pathogenic mechanisms, like coronary vasospasm, plaque activation and systemic hypotension, have been suggested. The hypothesis of a central role of mast cell and inflammatory cell activation and release of potent vasoactive mediators, inducing the mechanisms mentioned above, is the mainstay of so-called "cardiac anaphylaxis". We report two cases of anaphylaxis-induced acute ST-segment elevation myocardial ischemia which occurred during coronary angiography. The first one was probably related to contrast media contact, the second one to latex glove contact. Both of them were treated with percutaneous coronary intervention that immediately resolved the myocardial ischemia.

Systematic follow-up increases incidence of anaphylaxis during adverse reactions in anesthetized patients

BACKGROUND

The incidence of hypersensitivity reactions during anesthesia is underestimated because clinical symptoms may vary and diagnosis is not obvious. Our aim was to investigate the consequences of a systematic follow-up of patients on the estimated incidence of allergic reactions during anesthesia.

METHODS

We conducted a prospective study over a 2-year period (70,000 anesthesias). When patients were suspected with hypersensitivity reactions or with unexplained adverse reactions during anesthesia, blood was sampled to measure histamine and tryptase, and then skin tests were performed 4-6 weeks later.

RESULTS

During the studied period, 39 patients were enrolled in the database. Eight were excluded because of lack of skin tests. Twenty-two patients had clinical features compatible with immediate hypersensitivity reaction, and nine had reactions rated as 'unexplained' by the attending physician. Following systematic investigation, we found 22 hypersensitivity reactions (15 patients with obvious and seven with unexplained reactions) during anesthesia. This increases the estimated incidence of hypersensitivity reactions from 1 : 4667 to 1 : 3180 anesthesias. Tryptase concentrations were increased in only 50% of these patients. In our series, positive and negative predictive values of tryptase at T(0) for the diagnosis of anaphylaxis were 100% and 60%, respectively. Latex was the major causative agent, followed by neuromuscular blocking agents and antibiotics.

CONCLUSIONS

Systematic follow-up of patients with unexplained reactions during anesthesia increases the estimated incidence of IgE-mediated hypersensitivity reactions during anesthesia by 50%.

[Epidemiology and etiologic agents of occupational asthma]

INTRODUCTION

Occupational asthma is, by definition, a disease that can be prevented through appropriate protective strategies. Epidemiological information is required to guide these interventions, and we here examine epidemiological data on the burden, causes, and risk factors for this condition.

STATE OF THE ART

Population-based surveys indicate that approximately 15% of adult asthma is attributable to the workplace environment. The most common occupational agents implicated include flour, isocyanates, latex, and persulphate salts. The occupations in which occupational asthma has been most commonly reported are bakers, spray painters, health-care workers, hairdressers, and cleaners. The level of exposure to sensitizing agents seems to be the most relevant risk factor. Atopy is a significant risk factor only for the development of sensitization to high molecular weight agents. The role of other individual determinants, such as genetic factors, has been less consistently established. Occupational asthma is associated with a substantial adverse impact on the employment and financial status of affected workers.

PERSPECTIVES

Methodological improvements are required in order to distinguish more accurately between occupational and work-exacerbated asthma. Further investigations of the effectiveness of primary and secondary preventive interventions are also needed.

Priming-like effect and successful desensitization after anaphylactic shock by latex sublingual immunotherapy

The present report deals with some unusual events observed restarting allergy vaccine in a case of anaphylactic shock which occurred giving the maximum scheduled dose (25 drops) of rush sublingual immunotherapy (SLIT) to latex. Restarting SLIT by usual (not rush) scheme we observed long-lasting fall of reactivity threshold. The maximum tolerable dose was reduced to 2 drops, a dose fivefold smaller than the one well tolerated during previous rush phase (10 drops). We have excluded a possible nocebo effect and proved that the reduced tolerance was real by double blind placebo-controlled challenge test. We have considered this effect in some ways similar to priming effect. SLIT was continued with two drops every day. After about twenty months we could demostrate a significant reduction of skin reactivity by end-point technique and an improved response to the controlled exposition to latex by use-tests. In the same time the tolerance to vaccine was improved to three drops. The better safety profile allowed us to restart and continue with SLIT also in the reported case of anaphlicatic shock by latex vaccine and, after about two years, to induce valuable hyposensitization. Latex SLIT is confirmed as a safe and effective method.

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.

Prevalence of latex allergy in spina bifida: genetic and environmental risk factors

AIM OF STUDY

To evaluate the prevalence of latex allergy in a population of children with spina bifida (SB) and to assess the role of early exposure to latex products and others risk factors.

INTRODUCTION

SB is related with an higher incidence of latex allergic reactions. These patients received repeated surgical procedures, implant of latex-containing materials and catheterization.

MATERIALS AND METHODS

Eighty consecutive subjects affected with SB besides answering a questionnaire, underwent a skin-prick test (SPT) to latex and the determination of the specific serum IgE (RAST CAP) to latex. 40% (32/80) of the patients showed a latex sensitization with specific IgE > 0.7 kU/I but only twelve of the 32 sensitized patients (40%) suffered from clinical reactions to latex (urticaria, conjunctivitis, angioedema, rhinitis, bronchial asthma). Number of surgical procedures, but particularly early exposure to latex and familiarity for allergy are correlated with latex allergy (p < 0.01).

CONCLUSION

Latex allergy in SB children is multifactorial situation related with a disease-associated propensity for latex sensitization, early exposure and number of surgical procedures. Prophylactic measures to avoid the exposure, not only in the sanitary environment, through the institution of latex-safe routes and every day, prevent potentially serious allergic reactions.

Condom leukoderma

Contact dermatitis from natural latex of condom has been reported and is attributed to latex sensitivity. Chemical leukoderma from rubber condom is probably not reported. Here we present a case of chemical leukoderma in a 32-year-old male who developed depigmentation around the shaft of the penis in a circumferential pattern. Since the lesion was solitary and the site corresponded to the point of maximum contact of the condom, a diagnosis of contact leukoderma due to latex condom was thought of. Patch testing was done with mercaptobenzothiazole (MBT), dusting powder present in the condom and condom latex as such. The patient tested positive (3+) with mercaptobenzothiazole and the condom latex. On discontinuation of condom use and with UVB phototherapy, lesions repigmented in eight weeks.

Latex allergen sensitization and risk factors due to glove use by health care workers at public health units in Florianopolis, Brazil

BACKGROUND

Natural rubber latex allergy is a "new" illness whose prevalence has reached epidemic proportions in highly exposed populations such as health care professionals.

OBJECTIVE

The aim of the study was to evaluate the frequency of reactions to latex and risk factors due to glove use in health care workers (HCW) in Florianopolis, Santa Catarina, Brazil.

METHODS

We evaluated latex-related allergy in 260 HCW by means of a questionnaire, skin prick tests (SPT) and serum latex specific IgE antibody levels. The subjects were divided into two groups depending on level of exposure to latex gloves. Comparisons were made between the different variables and a risk score was calculated using logistic regression analysis.

RESULTS

Glove-related symptoms were observed in 57% of 140 HCW. Significant differences between HCW and control groups were found for the following symptoms: contact dermatitis (P < .0001), cutaneous rash (P < .0001), asthma or allergic rhinitis (P < .0001), symptoms associated with toy balloons (P < .0001), airborne glove powder causing latex allergen reaction (P < .0001), food allergy (P < .0001), fruit allergy (P < .0001) and multiple surgical interventions (P = .0052). Contact dermatitis and anaphylaxis were the main problems, with a high risk factor for the development of latex allergy. Logistic regression analysis showed a significant positive association between the risk of latex allergy and those subjects who reported more than 4 positive answers on the questionnaire (including SPT) (odds ratio 6.8; 95% confidence interval 0.7-60.3). No latex-related allergy symptoms were reported by the control group. Serological latex specific immunoglobulin (Ig) E antibody levels were negative for both groups.

CONCLUSION

It is essential to recognize which professionals are sensitized to latex in order to provide appropriate treatment and to establish adequate prevention.

Sublingual desensitization in children with congenital malformations and latex allergy

The frequency of latex allergy in children requiring multiple surgery ranges from 16.7% to 65%. The aim of this study was to investigate the safety and efficacy of latex desensitization in a group of 10 patients with a history of multiple surgical procedures and clinically manifested allergy to latex. We selected 10 children (female-male ratio = 5:5), aged 4-16 yr (mean +/- s.d.: 9 +/- 4), with a history of multiple surgical procedures, adverse reactions to latex and positive skin test to latex and/or specific immunoglobulin E (IgE). Latex allergy diagnosis was confirmed by specific provocation tests (cutaneous, sublingual, mucous, conjunctival tests). Rush (4-day) sublingual desensitization was performed with increasing doses of latex extract (ALK Abellò) under patients' tongue until the highest dose of 500 microg of latex. A maintenance therapy (10 drops of undiluted solution three times a week) was recommended. During the 2-yr follow-up mean values of specific IgG4 and IgE, eosinophilic cationic protein and total IgE did not show significant variations. Patients did not manifest any adverse effect during the rush phase and only two patients manifested mild local symptoms during the maintenance therapy. All the challenges showed a reduction in terms of percentage of positivity and mean scores. All the patients showed a reduction of the mean individual score (p < 0.001). Furthermore patients who needed dental examination or surgery underwent such procedures without the occurrence of symptoms. Our preliminary results show sublingual desensitization to latex can be an important therapeutic tool in the management of young allergic patients requiring multiple operations.

Glove allergy and sensitization to natural rubber latex among nursing staff at Srinagarind Hospital, Khon Kaen, Thailand

BACKGROUND

According to studies from different countries, the prevalence of natural rubber latex (NRL) sensitization in healthcare workers ranges from 2.9 to 17%. The incidence and prevalence of sensitization and allergy to NRL in Thailand is limited to two studies. There is no study among the high risk healthcare workers.

OBJECTIVES

1) To estimate the prevalence of natural rubber latex (NRL) glove allergy and NRL sensitization among nurses; 2) To describe its clinical symptoms.

MATERIAL AND METHOD

Included in the present study were 412 nursing and medical record staff. A self-administered questionnaire was used to collect personal biodata and individual allergy histories to NRL products. Skin prick tests (SPTs) with the commercial NRL allergens; Stallergènes, S.A, Fresnes, France, and common environmental allergens, were performed.

RESULTS

The questionnaire response rate was 88% (412/470), 93% females. The response rate of SPT was 72% (295/412) (95%CI 67.2, 76.0). The prevalence of NRL glove allergic symptoms and NRL sensitization was 24% (95%CI 19.9, 28.1) and 2% (95%CI 0.4, 3.6), respectively. The mostfrequently reported symptoms among the positive SPT to NRL was angioedema. Five of the six NRL sensitised subjects had had high exposure to NRL.

CONCLUSION

NRL sensitization among Thai nursing staff is less prevalent than in healthcare workers in Europe.

Adverse reactions to latex products: preventive and therapeutic strategies

Evidence-based infection control/exposure control practices are evolutionary in nature. Elements of historical note were first recorded with the suggestions of Lister for guidelines on aseptic procedures. Others, like Semmelweis, promoted the practice of hand washing by medical students and physicians prior to leaving autopsy suites and before entering the labor and delivery areas of hospitals. Halstead is credited with being the first to use surgical gloves in a clinical setting. While the use of latex surgical gloves became routine by the end of World War I, it wasn't until the adoption of universal precautions by the Centers for Disease Control in 1987 that the use of gloves was officially expanded to cover virtually all aspects of patient care. The ubiquitous use of latex gloves and other latex products in healthcare has resulted in a parallel increase in latex-associated adverse reactions. To provide for a safe environment for both oral healthcare providers and patients alike, clinicians must understand the basis for latex-related adverse reactions, recognize associated signs and symptoms, and initiate appropriate preventive and therapeutic strategies. The recommendations for preventing/minimizing latex allergy in the oral healthcare setting are based on current knowledge and a common sense approach to the problem. Evolving manufacturing technology and improvements in measurement methods (for latex proteins) may lead to changes in these recommendations in the future.

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.