Challenge tests in the diagnosis of latex allergy.

The aim of this study is to evaluate the sensitivity, specificity and safety of challenge tests and their usefulness in the diagnosis of latex allergy. Forty adult subjects (F/M = 34/6, aged 18-66 yrs) with a history of adverse reactions after latex exposure and positive prick test and/or specific IgE to latex were enrolled. They were compared with 20 control subjects. They underwent provocative (cutaneous, mucous-oral, sublingual, conjunctival, nasal, bronchial, vaginal) tests. Symptoms and drug scores were recorded for each patient during challenges. All patients reacted to at least one of the following: cutaneous, nasal and conjunctival tests. No systemic reactions requiring epinephrine occurred. Of the challenges, the vaginal test resulted as the safest, but it had low sensitivity and many limits related to the procedure. According to our data, bronchial and nasal tests had the highest sensitivity (76% and 82% respectively), and were more precise than other tests in determining latex exposure and symptoms, but the bronchial test also presented the highest rate of risk. Mucous and cutaneous tests resulted as the most reliable. For all the tests, specificity and positive predictive value were 100%. All control subjects resulted negative to all challenges. There were no statistically significant changes in skin and serologic tests between the first and second visits. Correlations between MIS and skin tests and between MIS and serum tests were not found. Challenges can be considered safe diagnostic procedures. Tests that most faithfully reproduce natural exposure, on the basis of a patient's history, are preferable.

Sublingual-oral rush desensitization to mixed cow and sheep milk: a case report.

We attempted an oral rush desensitization with mixed cow and sheep milk in a 6-year-old boy who had had adverse reactions to cow and goat milks. Skin prick tests and specific immunoglobulin (Ig) E to cow, sheep and goat milks were positive. The double-blind, placebo-controlled food challenge with cow milk was positive too. He underwent a 12-day sublingual-oral desensitization treatment with mixed cow and sheep milk. Specific IgE and IgG4 were measured. Open oral challenges with cow milk, sheep milk and sheep cheeses were also performed after the desensitization. At the end of the desensitizing treatment our patient could tolerate 120 mL of mixed milk. Specific IgE levels did not vary, whereas an increase of specific IgG4 concentrations was observed. Open oral challenges with cow and sheep milks and sheep cheeses were negative. Oral rush desensitization may represent an alternative approach to the treatment of food allergy in children.

Anaphylactic reactions during cesarean section.

Sensitization to latex seems to occur more frequently in women than in men. Obstetric and gynecological surgical procedures have recently been shown to be a common setting for latex anaphylaxis. We analyzed all the cases of anaphylactic reactions during 1240 cesarean sections in 2004; the patients were questioned for risk factors and underwent allergy testing for drugs and latex. Four patients had anaphylaxis under spinal anesthesia and in all cases it was due to latex allergy. Reported symptoms included facial edema, profuse sweating, itching, generalized erythematous rash and hypotension. Only one patient manifested a severe reaction which included bronchospasm, dyspnea, tachypnea and anaphylactic shock, requiring orotracheal intubation and epinephrine. Our data showed a high incidence (1:310) of intraoperative latex anaphylactic reactions in the one-year study period. This may be related to the very specific population (all women) in a very specific setting (obstetrics). To prevent anaphylactic reactions during obstetric surgery it is important to identify potential risk factors to include, for example atopy, adverse reactions to foods and latex items. If latex allergy is confirmed or strongly suspected, patients should be managed in a latex-safe environment. Premedication with antihistamines and steroids might be useful to further reduce the risk. After the delivery, specific desensitization may represent a good therapeutic option.

Delayed allergy to aminopenicillins: clinical and immunological findings.

Aminopenicillins are the most used beta-lactam antibiotics. Morbilliform or maculopapular rashes are rather frequent during therapy with aminopenicillins. The pathogenesis of these reactions is often due to a cell-mediated allergy. The aim of this work is to characterize patients with cell-mediated allergy to aminopenicillins and to identify alternative beta-lactam drugs that can be safely administered to these patients. We studied 27 subjects affected by cell-mediated allergy to aminopenicillins. The diagnosis was made on the basis of positivity of patch tests with aminopenicillins. These patients then underwent an allergological evaluation (skin and patch tests, oral and/or intramuscular challenge tests) with a wide spectrum of beta-lactam antibiotics. Our work highlights the following main characteristics of cell-mediated allergy to aminopenicillins: time elapsing between drug administration and onset of symptoms of about 2 days; the maculopapular rash and delayed appearance of urticaria/angioedema were the most typical symptoms (82.8 percent of cases); a cross-reactivity with aminocephalosporins is usually absent, or it is limited to cephalexin (in our study, in fact, just 3 out of 20 patients challenged with cephalexin showed a positive oral challenge test); all the beta-lactams, other than aminopenicillins, are well tolerated. Patch tests represent a specific diagnostic tool with a good predictive value of identifying alternative drugs that can be safely administered to patients with beta-lactam allergy. Our patients could tolerate other beta-lactam drugs after a complete allergological evaluation. On the basis of our study, cell-mediated allergy to aminopenicillins should be considered a well-defined nosologic entity.

A clinical trial of oral hyposensitization in systemic allergy to nickel.

Nickel allergy is the most common contact allergy. Some nickel-sensitive patients present systemic (cutaneous and/or digestive) symptoms related to the ingestion of high nickel-content foods, which significantly improve after a specific low nickel-content diet. The etiopathogenetic role of nickel in the genesis of systemic disorders is, furthermore, demonstrated by the relapse of previous contact lesions, appearance of widespread eczema and generalized urticaria-like lesions after oral nickel challenge test. The aim of this study is to investigate the safety and efficacy of a specific oral hyposensitization to nickel in patients with both local contact disorders and systemic symptoms after the ingestion of nickel-containing foods. Inclusion criteria for the recruitment of these patients were (other than a positive patch test) a benefit higher than 80% from a low nickel-content diet and a positive oral challenge with nickel. Based on the previous experiences, our group adopted a therapeutic protocol by using increasing oral doses of nickel sulfate associated to an elimination diet. Results have been excellent: this treatment has been effective in inducing clinical tolerance to nickel-containing foods, with a low incidence of side effects (gastric pyrosis, itching erythema).

Oral rush desensitization with tomato: a case report.

Adverse food reaction in which no immunological mechanism is demonstrated should be termed nonallergic food hypersensitivity or food intolerance. We present the case of a 12-year-old girl with a clinical history of abdominal pain, nausea, and general malaise after tomato intake which completely remitted with antihistamines. The patient underwent a complete allergy evaluation: skin prick tests, serum specific IgE and IgG4 tests to tomato, and double-blind placebo-controlled food challenge. Skin prick tests and specific IgE to tomato were negative while the food challenge was positive. At the end of the workup, the patient underwent an oral rush desensitizing treatment. At the end of the treatment the patient could eat a maintenance dose of 100 g of tomato daily with no side effects at all. This successful result suggests that the oral desensitizing treatment can be used in patients with nonallergic food hypersensitivity.

An attempt of specific desensitising treatment with gliadin in celiac disease.

Gluten-free diet is the current treatment of celiac disease. We decided to verify the occurrence of histological and serological modification and/or clinical manifestations during a gradual and progressive introduction of gliadin in the diet and if it may induce a tolerance to food, as it occurs in allergic patients. We studied the case of a celiac woman with complete clinical and histological remittance after 10 years of gluten free diet. She took increasing daily doses of gliadin, reaching the final dose of 9 g of gliadin (15 g of gluten) in 6 months. Then she started a free dietary regimen. During the 15-month follow-up period esophago-gastro-duodenoscopy showed normal Kerckring folds and villi. Anti-gliadin, anti-endomysium and anti-tissue-transglutaminase antibodies, as well as the haematological and biochemical parameters remained normal. Our results represent a new approach in research concerning celiac disease, and could provide a future line of study for its management.

Oral desensitizing treatment in food allergy: clinical and immunological results.

BACKGROUND: The possibility of inducing oral desensitization in patients with food allergy is still controversial and no standardized programmes are yet available. AIM: To evaluate the safety and efficacy of oral desensitization in patients with allergy induced by the most common food allergens. METHODS: Fifty-nine patients with food allergy underwent an oral desensitizing treatment according to standardized protocols. The control group consisted of age- and sex-matched subjects, who followed a strict elimination diet. Specific immunoglobulin E and immunoglobulin G4 were assessed at baseline and after 6, 12 and 18 months. RESULTS: The majority of patients (83.3%) successfully completed the treatment. During treatment, 51.1% of subjects experienced some mild side-effects, easily controlled by the oral administration of antihistamines or sodium cromolyn. Specific immunoglobulin E showed a significant decrease, whilst specific immunoglobulin G4 showed a significant increase in all patients. CONCLUSIONS: The immunological findings induced by oral desensitization in food allergy allow us to hypothesize that oral tolerance may be mediated by the same mechanisms as those involved in traditional desensitizing treatments for respiratory allergies. Moreover, the proposed standardized oral desensitization protocols may represent an effective alternative approach in the management of food-allergic patients.

Desensitization to latex by percutaneous route.

Latex allergy is a newly emerging problem. In the last decades its prevalence has increased progressively, especially among health care personnel and patients. Preventive measures have been suggested to reduce the risk of sensitization, but this is very difficult because of the ubiquity of latex products. Since only two clinical reports are available in the literature, suggesting that subcutaneous desensitizing treatments resulted in important side effects, we decided to attempt a desensitization through alternative routes. After having succeeded in carrying out sublingual desensitization, we report the case of a latex-allergic patient who successfully underwent percutaneous desensitization.

Demonstration of an IgE-mediated immunological pathogenesis of a severe adverse reaction to gadopentetate dimeglumine.

In this case report, the authors, after reviewing the literature data about contrast agents in Magnetic Resonance Imaging (MRI) and correlated problems, investigate the immunological mechanism of an adverse reaction to gadopentetate dimeglumine (Gd-DTPA), in order to demonstrate an IgE-mediated immunological pathogenesis. The case of a patient who underwent MR imaging in our hospital was studied. During, and after, the MR examination with Gd-DTPA the patient showed local warmth/pain to the external genitalia and to the face, tachycardia, nausea, vomiting, diarrhea, uterine cramps, and diffuse cutaneous rash. Skin tests (intradermal) and the passive transfer test according to Prausnitz and Küstner were positive, suggesting the involvement of an I-type allergy (IgE-mediated) mechanism. In this paper, we demonstrate that the adverse reactions to Gd-DTPA can be supported by an immunological mechanism.

Sublingual immunotherapy for latex allergy: tolerability and safety profile of rush build-up phase.

OBJECTIVE: Sublingual immunotherapy represents an efficient therapeutic tool for the management of latex allergic patients. Local and systemic adverse reactions are reported, and risk factors for those reactions are poorly understood. The aim of this study is to compare two different rush induction protocols (2-day and 3-day) in terms of safety and tolerability and effectiveness in reaching the maintenance dose. METHODS: Twenty-three outpatients (F/M = 18:5; 5-64 years of age), with latex allergy were randomly assigned to: Group 1 (2-day) and Group 2 (3-day). Adverse reactions were classified by their type and severity. RESULTS: Twenty-one subjects, 10 from Group 1 and 11 from Group 2, reached the maintenance dose, 70% of them without side effects. Seven adverse events were reported in Group 1: three were local (oral itching) and spontaneously remitted; four were systemic (Grade-2: two reactions; Grade-3: two reactions) and were effectively controlled with drugs. The protocol was interrupted in two cases because of recurrent reactions. No reactions were reported in Group 2. Age, gender, atopy, specific IgE, skin prick tests and sublingual challenge did not seem to influence the risk of side effects significantly. No significant modification of skin tests and specific IgE levels were reported in both groups. The cutaneous test turned negative in 16 patients, eight from Group 1 (80%) and eight from Group 2 (73%). The remaining patients (two from Group 1 and three from Group 2) showed a reduction of latex reactivity, in terms of symptom score (MIS: 2 vs. 0.5 in Group 1, 3 vs. 1 in Group 2). CONCLUSIONS: This study confirms the safety of rush induction. The 3-day protocol was better tolerated than the 2-day. Significant risk factors for the occurrence of adverse reactions were not identified. Only the type of protocol but not patient-related parameters seemed predictive of side-effects.

Latex sensitisation and allergy in children with myelomeningocele.

INTRODUCTION: Children with spina bifida (SB) have a high degree of exposure to latex products as a consequence of repeated surgical procedures, implantation of latex-containing materials and catheterisation. The consequence is a higher incidence of latex allergic reactions. OBJECTIVE: The aim of this study is to evaluate the prevalence of latex sensitisation and allergy in a population of children with myelomeningocele (MMC) and to assess the role of associated risk factors. RESULTS: Forty-eight percent of the patients (29 out of 60) showed a latex sensitisation with specific IgE >0.7 kU/l while 15% (9 out of 60) were allergic to latex (specific IgE >0.7 kU/l and clinical manifestations). The principal factor correlated with allergy to latex was specific serum IgE to latex (radioallergosorbent test [RAST]) values (p<0.01). Other factors were total serum IgE (paper radioimmunosorbent test [PRIST]) values, number of surgical procedures and familiarity with allergy. CONCLUSION: These results underline the importance of prophylactic measures to avoid the exposure, not only in the sanitary environment, through the institution of latex-safe routes, but also in daily life, to prevent potentially serious allergic reactions.

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.

Oral desensitisation in cow milk allergy: immunological findings.

In the literature there are several reports dealing with the possibility of a desensitising treatment in food allergy, but there are very few studies about the immunological mechanisms of oral desensitisation. We studied the immunological modifications in four children who underwent oral desensitisation with cow milk. Four children with cow milk allergy underwent oral desensitisation according to a standardized protocol. Total IgE, eosinophilic cationic protein in serum, and specific IgE and IgG4 to α-lactalbumin, to β-lactoglobulin and to casein were determined at the beginning of the treatment and after 6, 12 and 18 months in the 4 children treated. All the 4 treated patients successfully completed the treatment. Specific IgE to casein showed a significant reduction (p<0.01), while specific IgG4 to α-lactalbumin (p<0.02), to β-lactoglobulin (p<0.01) and to casein (p<0.01) showed a significant increase. Total IgE, eosinophilic cationic protein, and specific IgE to α-lactalbumin and to β-lactoglobulin did not show any significant modification. Control patients did not show any immunological modification and still had a positive double-blind, placebo-controlled food challenge. These results make us think that oral desensitisation in food allergy happens with the same mechanisms of traditional desensitising treatments for respiratory and insect sting allergies.

Positive patch tests to Euro coins in nickel-sensitized patients.

BACKGROUND: Many efforts have been made to prevent nickel allergy, the most frequent contact allergy in industrialized countries, by identifying acceptable limits of exposure. Even though coins are not covered by the EU Nickel Directive, some authors suggest that nickel release from coins during handling may elicit contact dermatitis in nickel-allergic people. OBJECTIVES: To evaluate sensitivity to nickel released from coins in nickel-allergic patients and to verify whether nickel release from the new Euro coins may elicit stronger cutaneous reactivity than from old Italian lire coins. METHODS: Twenty-five nickel-allergic patients were patch tested with 1- and 2-Euro coins, 1-, 2- and 50-Euro cent coins, and 100 and 500 Italian lire coins. Ten healthy nonnickel-allergic control individuals were also tested. RESULTS: Nineteen patients had positive patch tests to 1- and 2-Euro coins. One was also positive to 1- and 2-Euro cent coins, four to 50-Euro cent coins, and 13 to the 500-lire coin. None had a positive patch test to the 100-lire coin. The number and degree of positive patch tests to coins were related to nickel content. CONCLUSIONS: Euro coins may be potentially more dangerous than old Italian coins. Coins containing little or no nickel should be chosen for coinage to prevent sensitization and to avoid exacerbation of contact dermatitis in nickel-allergic patients.