Lessons from peculiar cases of anaphylaxis: why allergists should be prepared for the unexpected

Summary

Anaphylaxis is the most severe systemic hypersensitivity reaction, it can be caused by a number of well identified triggers such as foods, drugs, stinging insects and facilitated by predisposing clinical conditions. However, sometimes anaphylaxis shows up with uncommon or peculiar characteristics which could delay diagnosis and therapeutic treatment. In this report we aimed to describe less accounted / difficult-to-approach shapes of anaphylaxis to facilitate clinicians to suspect these severe reactions even in uncommon conditions. We choose to present data on anaphylaxis regarding simulation, mode of exposure to sensitizing agents, pregnancy, exposure to animals, intimate behaviour, psychological stress and other situations.

Allergy in adolescent population (14-18 years) living in Campania region (Southern Italy). A multicenter study

Summary

Adolescents (Ad) constitute a difficult to manage population among individuals suffering from asthma. The aim of our study was to assess the prevalence, clinical characteristics and age of onset of allergic sensitization and clinical symptoms in a sample of atopic Ad living in the Campania region (Southern Italy). Sixteen Allergy units or Centers belonging to the Italian Association of Hospital and Territorial Allergologists (AAIITO, Campania region) participated in this cross-sectional study. A case report form (CRF) was specifically designed for this study and commercial allergen extracts used for screening SPTs were provided by ALK-Abelló Group (Milan, Italy). A total of 443 patients were examined (females, f 220, 49.6 %; males, m 223, 50.3%). Dust mites represent the most common sensitizing agents in allergic Ad living in Campania region (Dermatoph. pteronyssinus 67.4% and Dermatoph. farinae 66.5%), followed by Parietaria (58.9%), grasses (45.8%), Artemisia vulgaris (16.7%), Olea Europaea (32.2%), dog dander (17.1%), cat dander (20.0%), Alternaria alternata (8.1%), Cupressus sempervirens (4.9%), Betula pendula (4.7%), other allergens (19.4%). An interesting comparison has been made between clinical data of our Ad with data of elderly patients (E). The role of allergic sensitization is significantly higher in Ad compared to E. Dermatophagoides pteronyssinus is the first sensitizing allergen in Ad and the last in E. Parietaria constitutes the first sensitizing pollen both in Ad and E, the percentage of sensitization is higher in Ad. Another important difference is the higher prevalence of As, as only symptom, in E compared to Ad (19.7% versus 7.6%). In conclusion, our findings confirm the high prevalence and clinical significance of airway allergic sensitization in the adolescents living in Campania region.

Allergic sensitization to common pets (cats/dogs) according to different possible modalities of exposure: an Italian Multicenter Study

Background

The query "are there animals at home?" is usually administered for collecting information on anamnesis. This modality to consider exposure to pet allergens constitutes a potential bias in epidemiological studies and in clinical practice. The aim of our study was to evaluate/quantify different modalities of exposure to cat/dog in inducing allergic sensitization.

Methods

Thirty Italian Allergy units participated in this study. Each centre was required to collect the data of at least 20 consecutive outpatients sensitized to cat/dog allergens. A standardized form reported all demographic data and a particular attention was paid in relieving possible modalities of exposure to cat/dog.

Results

A total 723 patients sensitized to cat/dog were recorded, 359 (49.65%) reported direct pet contact, 213 patients (29.46%) were pet owners, and 146 subjects (20.19%) were exposed to pets in other settings. Other patients were sensitized by previous pet ownership (150-20.75%) or indirect contact (103-14.25%), in 111 subjects (15.35%) any contact was reported.

Conclusions

Only 213 patients (29.46%) would be classified as "exposed to animals" and 510 (70.54%) as "not exposed" according to usual query. Our classification has shown that many "not-exposed" subjects (399-55.19%) were "really exposed". The magnitude of exposure to pet allergens at home is not related exclusively to pet ownership. These considerations should be taken into account during the planning of epidemiological studies and in clinical practice for the management of pet allergic individuals.

Allergic sensitization to common pets (cats/dogs) according to different possible modalities of exposure: an Italian Multicenter Study

Background

The query “are there animals at home?” is usually administered for collecting information on anamnesis. This modality to consider exposure to pet allergens constitutes a potential bias in epidemiological studies and in clinical practice. The aim of our study was to evaluate/quantify different modalities of exposure to cat/dog in inducing allergic sensitization.

Methods

Thirty Italian Allergy units participated in this study. Each centre was required to collect the data of at least 20 consecutive outpatients sensitized to cat/dog allergens. A standardized form reported all demographic data and a particular attention was paid in relieving possible modalities of exposure to cat/dog.

Results

A total 723 patients sensitized to cat/dog were recorded, 359 (49.65%) reported direct pet contact, 213 patients (29.46%) were pet owners, and 146 subjects (20.19%) were exposed to pets in other settings. Other patients were sensitized by previous pet ownership (150–20.75%) or indirect contact (103–14.25%), in 111 subjects (15.35%) any contact was reported.

Conclusions

Only 213 patients (29.46%) would be classified as “exposed to animals” and 510 (70.54%) as “not exposed” according to usual query. Our classification has shown that many “not-exposed” subjects (399–55.19%) were “really exposed”. The magnitude of exposure to pet allergens at home is not related exclusively to pet ownership. These considerations should be taken into account during the planning of epidemiological studies and in clinical practice for the management of pet allergic individuals.

Allergy in urban elderly population living in Campania region (Southern Italy). A multicenter study

Given the increasing life expectancy observed in Western countries, there is a marked interest to know more about how aging could influence respiratory health. The aim of our study was to assess the prevalence, clinical characteristics and age of onset of allergic sensitization and clinical symptoms in a sample of atopic elders living in Campania region area (Southern Italy). Fourteen Allergy units or Centres examined a total of 462 patients. In this context 215 (46.53%) had positive skin prick tests (SPTs) to at least one allergen and were diagnosed with respiratory allergy. Parietaria represents the most common sensitizing agent in elders living in Campania region, followed by dust mites, grass pollen and Olea europaea. A relatively high percentage of atopic subjects suffered from respiratory symptoms at a fairly advanced age, namely 8.3% at 60-64 years, 10.2% at 65-70 and 5.7% at > 70 years. In conclusion, the prevalence and clinical significance of airway allergic sensitization in the elderly living in Campania region is more significant than expected in latter stages of life. Physicians should not neglect the role of atopy as a risk factor for the onset of allergic respiratory symptoms even in elderly patients.

Sensitization to cockroach allergens in the urban atopic populations living in Campania district (southern Italy). A multicenter study

BACKGROUND

Although cockroach (CR) is an important cause of allergic sensitization worldwide, only a few data are available in Italy and in a previous study we have observed, in Naples area, a low prevalence of CR sensitization.

OBJECTIVES

We sought to perform a prospective study for assessing the prevalence of allergic sensitization to CR in a sample of atopic population living in Campania district area (Southern Italy).

METHODS

Ten Allergy Units or Centres of Campania district participated in this cross-sectional study. Each centre was required to collect the results of at least 100 allergy consultations in consecutive outpatients referred for actual or suspected respiratory allergy. We registered demographic data, type and duration of respiratory symptoms, pets ownership, possible exposure to CR allergens, results of the skin prick tests (SPTs).

RESULTS

A total of 1477 patients were examined, 985 (66.68%) had a SPTs positivity to at least one allergen. In this context, ninety were sensitized to CR, thus the overall sensitization prevalence in subjects with respiratory allergy was 6.09% ranging between 0-11% and only five patients were mono-sensitized. Thirteen patients reported rhinitis (R) + bronchial asthma (A), twenty-one R + A + conjunctivitis (C), thirty-seven R + C, five only A and eleven individuals only R. Sixty-seven patients exhibited persistent and twenty-three intermittent symptoms. Dust mite constituted the first cause of associated sensitization to CR.

CONCLUSIONS

The prevalence of allergic sensitization to CR is not negligible in population living in Campania district and shows a higher trend in comparison to that found recently and some years ago in Naples area. Finally, we suggest atopic individuals and especially those highly sensitized to mite allergens or those living in low-income areas to be tested by SPTs / evaluation of serum specific IgE to CR allergens to exclude the occurrence of CR allergic sensitization.

Perioperative anaphylactic risk score for risk-oriented premedication

Basing on the current knowledge, this paper is aimed to review the core characteristics of the most relevant therapeutic agents (steroids and antihistamines), administered to prevent perioperative anaphylaxis. Moreover, the Authors propose the validation of a Global Anaphylactic Risk Score, built up by recording the individual scores related to the most relevant anaphylaxis parameters (i.e. medical history, symptoms and medication for asthma, rhinitis and urticaria etc) and by adding them on all together; the score could be used in the preoperative phase to evaluate the global anaphylactic risk and to prescribe risk-oriented premedication protocols.

Sensitization to horse allergens in Italy: a multicentre study in urban atopic subjects without occupational exposure

BACKGROUND

Horses play a significant role in people's leisure time in Italy and other countries, but few data are available on IgE-mediated sensitization to horse allergens in patients without occupational exposure. We assessed, in a multicentric survey, the prevalence of horse sensitization in atopic subjects and its clinical characteristics.

METHODS

Allergists from the whole Italian territory were required to collect the results of skin prick tests from at least 100 consecutive subjects. Those patients with a positive skin test to horse dander underwent a detailed interview concerning clinical history, pet ownership and possible exposure.

RESULTS

Data from 3,235 outpatients were collected and 2,097 had at least 1 skin positivity. Among them, 113 (5.38%) were sensitized to horse dander (9 monosensitized). Thirty patients reported direct horse contact (4 owners and 26 for riding or occasional contact), 23 patients were sometimes in contact with horse owners and 60 subjects denied any direct or indirect exposure. Among 9 horse monosensitized patients, 6 had intermittent and mild rhinitis and 3 persistent moderate/severe rhinitis plus asthma. Three of them were horse owners or riders and the remaining had no contact with the animal.

CONCLUSIONS

Our data evidence that the rate of sensitization to horse dander is not negligible and probably underestimated. In susceptible, not occupationally exposed individuals, horse contact, but also indirect or no apparent exposure, may induce sensitization. We recommend inclusion of horse allergen in the routine panel for the diagnosis of respiratory allergy.

Long-term absence of sensitization to mepivacaine as assessed by a diagnostic protocol including patch testing

BACKGROUND

Prospective assessment of non-reactivity to local anaesthetics is a frequent reason for allergy consultation.

OBJECTIVES

To investigate the clinical profiles of subjects referred for allergy evaluation; to prospectively reduce the frequency of evaluation by assessing the persistence, during clinical use, of non-reactivity to contaminant/additive-free mepivacaine; and to determine the usefulness of a diagnostic protocol involving patch testing.

METHODS

In a prospective study, 198 consecutive patients underwent collection of clinical data, skin prick tests and patch tests using allergens/antigens relevant for the investigation, and an intradermal/subcutaneous challenge procedure using contaminant/additive-free mepivacaine, as appropriate. Patients were followed up for 3 years for assessment of non-reactivity persistence using the same diagnostic protocol.

RESULTS

Only one-third of the patients had a history of previous adverse local anaesthetic reactions. Absence of sensitization to contaminant/additive-free mepivacaine persisted in all subjects completing the follow-up. Controlled challenge with mepivacaine was negative in 196 patients with both negative specific skin prick tests and patch tests but it was eventful in two subjects with positive specific patch tests. A few subjects displayed positive skin prick tests and/or patch tests for latex and/or additives.

CONCLUSIONS

A few patients had a relevant history for potential local anaesthetic-induced adverse reactions. Upon assessment of absence of sensitization and reactivity, contaminant/additive-free mepivacaine could safely be given for as long as 3 years. The patch testing was shown to be useful and safe for prediction of challenge outcomes. True allergic reactions to contaminant/additive-free mepivacaine were not observed in our patient series.