Tiziana Maria De Pasquale

Oral Specific Desensitization in Food-Allergic Children

The possibility of obtaining oral desensitization in patients with food allergy is still a matter of debate. We decided to evaluate the safety and efficacy of standardized protocols for oral desensitization with the most common food allergens. Forty-two children (ages up to 16 years) diagnosed as affected by food allergy (on the basis of clinical history, skin prick tests, measurement of specific IgE, and double-blind, placebo-controlled food challenge) underwent a sublingual-oral desensitizing treatment according to new standardized protocols. The control group consisted of 10 patients who followed an elimination diet. The treatment was successfully completed by 85.7% of the patients. Specific IgE showed a significant decrease, while specific IgG4 showed a significant increase, in all treated patients. The immunological modifications observed in our patients lead us to hypothesize that oral tolerance may be mediated by the same mechanisms as those involved in traditional desensitizing treatments for respiratory and insect sting allergy.

Oral Rush Desensitization in Peanut Allergy: A Case Report

Allergy to peanuts represents one of the most severe food allergies, rarely remitting compared with milk and egg allergy and frequently associated with life-threatening allergic reactions (1, 2). Its prevalence in the United States is 1.1% (3). Clinical manifestations range from vomiting, diarrhea, and local or generalized urticaria–angioedema to dyspnea, hypotension, collapse, and anaphylactic shock (4). Ara h1, Ara h2, and Ara h3 have been identified as the major peanut allergens (5). Currently prolonged strict avoidance represents the only effective means to prevent allergic symptoms, but this is hardly feasible. Peanut-allergic patients are particularly vulnerable to accidental exposure because small traces (doses as low as 100 μg of protein) may provoke severe symptoms (6, 7). Results of peanut allergen monitoring showed a remarkable quantity of products (such as snacks, cereal bars, and potato snacks) with hidden allergen (8). Another study has shown how simple tasks such as shopping and eating in restaurants can be extremely frightening, even perceived as life-threatening (9). We report the case of a woman with peanut allergy who successfully underwent specific rush desensitization by the oral route (10–14).

Sublingual desensitization: a new approach to latex allergy problem

The prevalence of latex allergy has rapidly increased. Clinical manifestations range from contact urticaria-angioedema and rhinoconjunctivitis to more severe bronchial asthma and anaphylactic shock. The only effective therapy is desensitization. We studied 24 patients allergic to latex: 12 of them underwent a rush (4-day) sublingual desensitization to latex, performed by putting increasing doses of latex extract under the patients’ tongues for 3 min every 20 min, followed by a maintenance therapy. The other 12 patients were considered controls. The sublingual rush desensitization protocol was successfully completed in all patients with no side effects. After 3 mo, all patients underwent an allergological evaluation, which showed a significant improvement of symptoms scores after challenges in the treated group as compared with the controls. All the desensitized patients can now wear latex gloves and undergo medical procedures without any symptoms.

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 concerning the immunological mechanisms of or al 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 a-lactalbumin and to β-Iactoglobulin 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 occurs with the same mechanisms of traditional desensitising treatments for respiratory and insect sting allergies.

Multiple-drug intolerance syndrome: clinical findings and usefulness of challenge tests.

BACKGROUND Multiple-drug intolerance syndrome (MDIS) is characterized by adverse reactions to several classes of chemically unrelated drugs. OBJECTIVE To analyze all patients with a history of adverse reactions to at least 3 drugs at the Allergy Unit of Policlinico Gemelli in a 6-year period to better characterize patients with MDIS and to find safe alternative drugs. METHODS We studied 480 patients (aged >16 years) with a history of adverse reactions to at least 3 unrelated drugs and with negative allergy test results. Patients who had experienced mild adverse reactions that remitted spontaneously underwent challenge tests without any premedication (group A). Patients with a clinical history of moderate reactions received sodium cromolyn, 500 mg, before the challenge (group B). Patients with a clinical history of severe reactions or undergoing parenteral challenges were given an antihistamine 30 minutes before the challenge (group C). RESULTS In group A, 491 tolerance challenge tests were performed: 414 had negative results and 77 had positive results. In group B, 1,077 tolerance challenge tests were performed: 956 had negative results and 121 had positive results. In group C, 240 tolerance challenge tests were performed: 214 had negative results and 26 had positive results. Comparing the tolerance of alternative drugs in groups A and B, groups A and C, and groups B and C, no significant results were observed (P = .24, .14, and .44, respectively). CONCLUSIONS Patients with MDIS can tolerate alternative drugs. Premedication with sodium cromolyn or oral H1-antihistamines may be useful in preventing adverse reactions.

Latex allergy desensitization by exposure protocol: Five case reports

Two clinical reports dealing with subcutaneous desensitization to latex are available, but these treatments were reported to have significant side effects. To investigate an alternative method for latex desensitization, we present five cases of immunoglobulin E-mediated latex allergy in which a specific desensitization was successfully performed by means of an original exposure protocol. Five female patients with proven latex allergy underwent an original contact desensitization by wearing latex gloves daily, progressively increasing exposure to latex. All patients reached a final latex exposure time of 60 min in both hands. The desensitization protocol was completely successful in all patients. Twelve months after the beginning of the desensitization program, all the treated subjects were able to wear latex gloves daily without any clinical manifestations. This study provides evidence that a successful contact desensitization to latex is possible with no side effects. The adopted exposure protocol seems to be completely safe and effective. However, further studies in larger groups of subjects are necessary to fully confirm these preliminary results.

Food allergy and food intolerance: diagnosis and treatment

Food allergy is a matter of concern because it affects about 0.5–3.8% of the paediatric population and 0.1–1% of adults, and as well may cause life-threatening reactions. Skin prick testing with food extracts and with fresh foods, the measurement of food-specific IgE, elimination diets and a double-blind, placebo-controlled food challenge are the main diagnostic procedures; many non-validated procedures are available, creating confusion among patients and physicians. The treatment of food allergy is still a matter of debate. Antihistamines, corticosteroids and, if necessary (in case of anaphylaxis), epinephrine, are the drugs of choice for the treatment of symptoms of food allergy. Sodium cromolyn may be used prophylactically even though there are no controlled studies certifying its efficacy. The only etiologic treatment of food allergy is specific desensitization. Sublingual-oral-specific desensitization has been used by our group for the treatment of food-allergic patients with a high percentage of success.

Delayed allergy to aminopenicillins: clinical and immunological findings

Aminopenicillins are the most used β-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 β-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 β-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% 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 β-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 β-lactam allergy. Our patients could tolerate other β-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 case of cutaneous delayed-type allergy to oral dexamethasone and to betamethasone.

Corticosteroids are drugs that may cause allergic contact dermatitis, but systemic allergic reactions to these drugs are rare. A 29-year-old man developed a maculopapular rash during an oral therapy with betamethasone. Patch tests demonstrated a delayed-type allergy to dexamethasone, betamethasone and fluocortolone. Oral, intramuscular or topical provocation tests with other corticosteroids – deflazacort, hydrocortisone, methylprednisolone, fluticasone dipropionate, triamcinolone and prednisone – were all negative. This demonstrates that a patient with a systemic allergy to a group of corticosteroids can tolerate those of other groups.

Allergic and non-allergic drug hypersensitivity reactions in children.

Adverse drug reactions (ADR) are an important medical problem. The aim of this study is to investigate the clinical characteristics of children with ADR and to assess the tolerability of alternative drugs in children (under 16 yrs of age) with a history of ADR. We studied 278 children (132 males and 146 females). Patients were studied by recording personal history and performing in vivo skin testing, in vitro laboratory tests and challenge tests. Patients who had experienced mild adverse reactions underwent challenge tests without any premedication; patients with a clinical history of moderate reactions, received a premedication with sodium cromolyn 30 min before the oral challenge; patients with a clinical history of severe reactions or undergoing parenteral challenges, were given an antihistamine 30 minutes before. A total of 660 adverse events were reported with 126 different drugs involved. Antimicrobial agents were the most involved drugs (51.7%). Non-steroidal anti-inflammatory drugs were involved in 22.7% of episodes. The most reported symptoms were cutaneous. Allergy testing was negative in 272 patients. A diagnosis of drug allergy was reported for 6 patients. A total of 669 challenge tests were performed. 639 were negative at first attempt while 22 were positive. Eight were repeated using a different premedication and resulted negative. Hypersensitivity drug reactions in children are mainly non-allergic. A premedication with sodium cromolyn or with oral H1-antihistamines may be useful in preventing ADR.