Cross-reactivity and tolerability of imipenem in patients with delayed-type, cell-mediated hypersensitivity to beta-lactams.

BACKGROUND: Administration of imipenem-cilastatin to patients with IgE-mediated hypersensitivity to beta-lactams has always been considered potentially harmful. Recent studies have demonstrated the tolerability of carbapenems (imipenem-cilastatin and meropenem) in patients with IgE-mediated hypersensitivity to beta-lactams; there are no studies on this topic regarding patients with cell-mediated allergy to beta-lactams. The aim of this study is to assess cross-reactivity and tolerability of imipenem in patients with cell-mediated allergy to beta-lactams. METHODS: From our database we selected 73 patients with cell-mediated allergy to beta-lactams, diagnosed by means of immediate-type skin tests, delayed reading intradermal tests, patch tests and detection of specific IgE. Patients with negative patch tests with imipenem-cilastatin underwent an intramuscular test dosing. RESULTS: Our patients had a total of 94 nonimmediate reactions to penicillins. All patients had positive patch tests and/or delayed reading intradermal tests for at least one of the penicillin reagent tested and negative immediate-type skin tests and specific IgE. Four patients out of 73 had a positive patch tests to at least one penicillin reagent and imipenem-cilastatin showing cross-reactivity. Sixty-four patients underwent the imipenem-cilastatin intramuscular test dosing and none of them had a clinical reaction. CONCLUSIONS: Our rate of cross-reactivity between imipenem-cilastatin and other beta-lactams was 5.5%. This result is different from previous findings and this may be explained by the fact that we investigated patients with cell-mediated allergy to beta-lactams. Patients with cell-mediated allergy to beta-lactams should undergo patch tests and a tolerance challenge test before treatment with imipenem-cilastatin.

Sublingual desensitization in patients with wasp venom allergy: preliminary results.

The aim of this paper is to assess in an open prospective pilot case-control study the tolerability, safety and efficacy of an ultra-rush sublingual immunotherapy (SLIT) protocol with Vespula venom in wasp allergic patients compared to subcutaneous immunotherapy (SCIT). Forty-one wasp allergic patients were treated with sublingual (SLIT group) or subcutaneous (SCIT group) ultrarush immunotherapy with Vespula venom extract. All patients underwent skin tests and serum specific IgE and IgG4 detection before enrollment and after 6, 12 and 24 months of immunotherapy. The SLIT group consisted of 21 (6 females and 15 males) patients who received increasing doses of Vespula venom (Aquagen, ALK-Abellò) until the final dose of 30 drops of extract in 3 hours, containing 100,000 SQ-U/ml. The maintenance dose was of 10 drops of pure venom extract 3 times a week, for a total dose of 100,000 SQ-U weekly (corresponding to 100 microgram of venom extract). The SCIT group consisted of 20 patients (16 males and 4 females) who were treated with subcutaneous ultrarush immunotherapy with Vespula venom extract (Pharmalgen, Alk-Abellò). Patients received 101.1 microgram of Vespula venom in 3 hours and were treated with 100 microgram of wasp venom monthly. During the ultrarush sublingual treatment 2 patients (9.5%) experienced mild side-effects. Specific IgE and specific IgG to wasp venom did not show any significant modification. Four patients were field-stung by a wasp during the treatment (for a total of 6 stings). Two patients (3 stings), with a previous clinical history of a grade III and IV reaction, did not experience any reaction. One patient, with a previous grade II reaction, showed a large local reaction. The fourth patient, with a previous grade III reaction, was re-stung twice (after 12 and 24 months) with two systemic reactions (SR) (mild throat constriction). During the ultrarush SCIT phase, 3 (15%) patients experienced side-effects: 2 of them showed a large local reaction and 1 had headache and stomach ache. Specific IgE showed a significant (P = 0.001) increase after 6 months of treatment and then returned to baseline levels while specific IgG showed a significant (P = 0.001) increase after 6, 12 and 24 months in comparison with baseline. Nine patients were field-stung during the treatment: 8 of them experienced large local reactions; one patient (11%) experienced an SR (dizziness). Our results, even if in a small number of patients, suggest that in patients with Hymenoptera sting allergy SLIT could be efficacious with a good tolerability profile when compared to SCIT. Larger studies are needed to assess efficacy, safety and tolerability profile of wasp venom SLIT.

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.