Rosanna Qualizza

Safety of hymenoptera venom immunotherapy: a systematic review

Introduction: The efficacy of venom immunotherapy (VIT) in patients with insect sting allergy is not questioned. However, its safety, especially when honeybee is used, is a matter of concern. Areas covered: A systematic review of the literature on VIT was done, with both aqueous and depot extracts, to compare the frequency of systemic reactions to honeybee and vespid venoms. A Medline search was performed using the keywords ‘venom immunotherapy’, ‘safety’ and ‘tolerability’. The articles obtained were analyzed regarding the total number of patients treated with either honeybee or vespid VIT, the number and severity of systemic reactions during therapy, the type of extract used (aqueous or depot) and the administration regimen. Expert opinion: The incidence of systemic reactions to VIT was 25.1% for honeybee venom and 5.8% for vespid venom (p < 0.0001), while it was similar with aqueous and depot extracts in the whole population of patients. This confirms that during VIT systemic reactions are significantly more frequent with honeybee venom compared with vespid venom, while there are no significant overall differences in systemic reactions between aqueous and depot extracts.

Seroprevalence of IgG anti-Toxocara species antibodies in a population of patients with suspected allergy

Background Toxocara canis is an intestinal nematode affecting dogs and cats, which causes human infection when embryonated eggs excreted in dog feces are ingested. Humans are paratenic hosts. Although the larvae do not develop into adult worms in the human body, they may migrate to various tissues and organs where they can survive for several years, giving rise to several clinical symptoms, which can present in allergy-like form. Methods Over 5 years, we examined 9985 patients referred for suspected allergies, based on symptoms such as dermatitis, urticaria, rhinitis, asthma, and conjunctivitis; 753 patients who had allergy tests negative or unrelated to clinical history were tested for seropositivity to T. canis by enzyme-linked immunosorbent assay (ELISA) or Western blotting (WB). Results In 240 patients (31.8%), ELISA or WB or both tests were positive for T. canis immunoglobulin G (IgG) antibodies: in particular, 64 of them (26.7%) were positive to ELISA, 110 (45.8%) to WB, and 66 (27.5%) to both tests. Asthma was the most common clinical presentation. Two thirds of patients underwent subsequent anthelmintic therapy and showed a complete remission of symptoms and, in 43% of patients retested by ELISA and WB, became negative to Toxocara. Conclusion These findings strongly suggest that T. canis plays a significant role in inducing chronic symptoms presenting as suspected allergies.

A Case of Apparent Contact Dermatitis Caused by Toxocara Infection

Infection from Toxocara species may give rise to a large array of clinical symptoms, including apparent manifestations of allergy such as asthma, urticaria/angioedema, and dermatitis. We report a case, thus far not described, of contact dermatitis attributed to nickel allergy but caused by Toxocara infection. The patient was a 53-year-old woman presenting from 10 years a dermatitis affecting head, neck, and thorax. Patch tests initially performed gave a positive result to nickel, but avoidance of contact with nickel did not result in recovery. The patient referred to our Allergy Service in 2010 because of dermatitis to feet. Patch testing confirmed the positive result for nickel, but expanding the investigation a positive result for IgG antibodies to Toxocara was detected by Western blotting and ELISA. Treatment with mebendazole achieved immediate efficacy on feet dermatitis. Then, two courses of treatment with albendazole resulted in complete regression of dermatitis accompanied by development of negative ELISA and Western blotting for Toxocara antibodies. This report adds another misleading presentation of Toxocara infection as apparent contact dermatitis caused by nickel and suggests bearing in mind, in cases of contact dermatitis not responding to avoidance of the responsible hapten and to medical treatment, the possible causative role of Toxocara.

A case of atopic dermatitis caused by Ascaris lumbricoides infection

BackgroundParasite infections stimulate total and specific IgE production that, in the case of Toxocara canis infection, corresponds to chronic allergic symptoms. There may also be other infections which have similar symptoms, such as Ascaris lumbricoides infection. Ascaris lumbricoides is a large nematode that causes abdominal pain, nausea, vomiting, bloating, anorexia and intermittent diarrhoea. Patients with ascaridiasis and high IgE levels may also have allergy-like symptoms such as asthma, urticaria and atopic dermatitis.Case presentationWe report a case of atopic dermatitis caused by Ascaris lumbricoides which shows the important role of parasitic infection in patients with long-lasting dermatitis. The patient was a 12-year old female suffering since early infancy from atopic dermatitis and asthma. She was treated for dermatitis with oral bethametasone and topical pimecrolimus with little benefit. After two cycles of mebendazole therapy, the patient showed progressive improvement of symptoms.ConclusionsIn patients with dermatitis, Ascaris lumbricoides infection should be not excluded: adequate anthelmintic treatment may result in complete regression from the disease.

A case of pleural effusion caused by infection from Toxocara canis

Methods The patient was a 56-year old Caucasian woman suffering from rheumatoid arthritis since 1995. She was subsequently diagnosed with Sjoegren’s syndrome and autoimmune thyroiditis. In 2009, the patient had a skin rash which disappeared after corticosteroid treatment. In January 2012 a routine chest X-ray detected a pleural effusion, that was treated by various cycles of antibiotics and corticosteroids without improvement. The patient was then referred to us because of a concomitant eosinophilia. She also had difficulty in breathing, and allergy was suspected as a possible cause. The patient underwent allergy tests, parasitological evaluation and a routine blood examination, including IgG antibodies to T. canis.

585 Chronic Idiopathic Urticaria and Neglected Toxocara Infection.

Background The diagnosis of chronic idiopathic urticaria is stated when all possible causes of urticaria are excluded. Toxocariasis is a parasitic infection induced by a nematode belonging to the family of Ascaridae with generally affects cats and dogs. Human infestation is caused by the accidental ingestion of embryonated eggs of Toxocara; the larvae do not develop into adult worms but may migrate to several organs, giving rise to a number of clinical expressions, including chronic urticaria. Methods From 2005 to 2011 in our Allergy Unit were selected 336 patients with a positive result for IgG antibodies to Toxocara canis as assessed by ELISA or Western blotting (WB). Of them, 52 patients (33 F, 19 M, age ranging from 19 to 76 years old), suffered from chronic urticaria that lasted from 3 to 10 years and was poorly responsive to antihistamines. In all these patients anthelmintic therapy was prescribed using mebendazole (one 100 mg tablet b.i.d. for 3 days), repeated after 20 days up to 3 times. In case of insufficient improvement, albendazole (one 400 mg b.i.d. for 5 days) was used, repeated after 2 months. Results All patients showed a complete remission of urticaria and a decrease in serum IgG levels to Toxocara canis. In 29 patients (60%) a negative result to ELISA and WB was observed. Conclusion These findings suggest taking into account the role of Toxocara canis in patients with apparent chronic idiopathic urticaria. In patients with positive IgG to Toxocara anthelmintic therapy achieves remission of urticaria.