[Skin sensitisation profiles of outpatients with symptoms of respiratory allergies]

Retrospective analysis of aeroallergen's sensitization patterns in Edmonton, Canada

Background

Sensitization to common environmental aeroallergens plays a significant role in the pathogenesis and severity of respiratory allergic disorders, specifically asthma and allergic rhinitis. Understanding sensitization patterns helps clinicians tailor care more effectively. This study examines patterns of sensitization to aeroallergens in subjects suspected of having an allergic disease in Edmonton and catchment area.

Methods

Retrospective chart review of skin prick test (SPT) results to 11 environmental aeroallergens performed between January 1st and June 30th 2014 at a University-based clinic, where patients are referred for SPT by allergists, respirologists, otolaryngologists, internists and general practitioners. Potential differences in aeroallergen sensitization patterns were evaluated.

Results

A total of 623 patients (36.9% males; 63.1% females), aged 4–84 years (mean age 38.6 years) had SPT done, of which 438 (70.3%) had a positive test for at least one aeroallergen (atopy). There were no significant sex differences in the frequency of atopy (males: 71.3% versus females: 69.7%; p = 0.373). The frequency of sensitivity to particular allergens among atopic subjects was: cat (53.1%), house dust mites (50.3%), grass (39.2%), birch (23.7%), alternaria (23.7%), dog (17.3%), poplar (12.1%), cedar (9.6%), aspergillus (9.6%), hormodendrum (8%), and penicillium (6.2%). Of 438 atopic patients, 110 (25.1%) were mono sensitized, 199 (45.4%) oligosensitized (2–3 allergens), and 129 (29.5%) polysensitized (≥ 4 allergens). There were no significant differences between males and females in the odds of being oligo-sensitized (OR: 0.95; 95% CI 0.58, 1.57). Polysensitization was significantly more frequent in males 37.2% than in females 24.8%; (OR: 0.95; 95% CI 0.58, 1.57).

Conclusion

Cat is the most frequent perennial allergen and timothy grass pollen the most frequent seasonal allergen in Edmonton and catchment area. There was no significant difference in the frequency of atopy between males and females. However, males were more likely to be polysensitized compared to females.

[Skin sensitisation profiles to inhalant allergens for patients in Tétouan city (North West of Morocco)]

The prevalence of respiratory allergies is increasing and is a serious global health problem. The objective of the study was to determine the prevalence of skin sensitization to inhalant allergens in patients consulting for respiratory allergy, to identify the main allergens involved and to evaluate the profile of skin prick-test reactivity related to sex, age and season. This retrospective study included 379 patients consulting during 2009-2012 in three private medical offices of Tetouan. Of the 379 patients, 39.6% were monosensitized and 60.4% polysensitized. The percentages of polysensitized patients were higher in patients exhibiting rhinoconjunctivitis and astma-rhinoconjunctivitis than in subjects with asthma. The prevalence of symptoms according to sex showed no significant difference (P=0.64). Regarding age, a significant difference was observed in the case of rhinoconjunctivitis (P<0.01), while asthma and asthma-rhinoconjunctivitis showed no significant difference. Sensitization to house dust mites was the most frequent followed by grasses, olives and Parietaria. The multiple correspondence analyses (ACM) showed that patients under 20-years of age with asthma and asthma-rhinoconjunctivitis profile are more associated with sensitization to mites during the spring and autumn. The 20-49-year age group was represented mainly by polysensitized patients with rhinoconjunctivitis. Sensitization to mites ranks first in Tetouan followed by the percentage of sensitized patients to grass pollen and olive. The ACM showed that the house dust mite asthma seems to affect more children and adolescents while the 20-49 year age of polysensitized group suffers significantly rhinoconjunctivitis.

[Allergic asthma in central Tunisia]

L'asthme allergique pose un réel problème de santé publique vu sa prévalence et son coût de prise en charge élevés. Etudier le profil clinique, fonctionnel respiratoire, allergologique, thérapeutique et évolutif de l'asthme allergique dans une région du centre tunisien. Etude rétrospective portant sur 1132 dossiers de patients porteurs d'asthme allergique suivis dans le service de pneumologie et d'allergologie à l'hôpital de Monastir (Tunisie). L’âge moyen est de 27 ± 12,5 ans. 61,1% des patients sont âgés entre 16 et 39 ans. Une prédominance féminine est notée (56,7%). L'identification de l'allergène en cause s'est basée essentiellement sur les tests cutanés allergologiques (99,4%). Les principaux pneumallergènes identifiés sont les acariens (91,2%), suivis par les pollens (22,8%) et les phanères des animaux (12%). La classification selon la sévérité a conclu à un asthme intermittent à persistant léger chez 87.1% de nos patients. Le traitement s'est basé essentiellement sur la corticothérapie inhalée (67,6%). L'asthme dans notre étude a été jugé contrôlé dans 68,3% des cas, partiellement contrôlé dans 24,8% et non contrôlé dans 6,9% des cas. L'asthme allergique est une affection répandue qui touche essentiellement le sujet jeune en pleine activité. Une prise en charge adéquate permet de contrôler la maladie et de réduire ses répercussions sur le patient et la collectivité.

[Sensitisation profile to airborne allergens of patients followed for asthma in Cotonou, Benin. A cross-sectional study using prick-tests]

RATIONALE

The sensitisation profile to airborne allergens of asthma patients followed in Benin is not known.

PATIENTS AND METHODS

A descriptive cross-sectional study was conducted from April to June 2013 at the hospital reference centre. A prick-test was performed in all adults with asthma consulting during this period. The standardized allergenic extracts tested were: mites (Dermatophagoides pteronyssinus [DP], Dermatophagoides farinae [DF] and Blomia tropicalis [BT]), cockroaches, 5 different grasses, Alternaria, dogs and cats. The test was positive when the diameter of the wheal was more than half that of the positive control and/or when the diameter of the wheal was ≥3mm than the negative control.

RESULTS

Of the 253 asthmatics tested, 247 (97.6%) had at least one positive skin reaction. The average age was 44 years, the sex ratio was 0.81. Sensitization to mites was the most frequent (99.6%), followed by cockroaches (71.3%), 5 grasses (71.3%), Alternaria (71%), dog (68%) and cat (63.6%). The average number of sensitivities was 5±2.

CONCLUSION

Asthmatics monitored in Cotonou have multiple sensitisations dominated by mites.

Patterns of skin prick test positivity in allergic patients: usefulness of a nationwide SPT chart review

BACKGROUND

A previous survey on allergens used by Mexican allergists in their skin prick test (SPT) panel showed wide variation. Humidity varies in different zones of Mexico. This might lead to differences in natural exposure and allergic sensitisation throughout the country. We aim to describe the SPT sensitivity patterns in the different climatic zones in Mexico and to show the usefulness of a structured SPT chart-review including multiple clinics in obtaining these allergen sensitisation patterns.

METHODS

A retrospective, structured chart-review of SPT results was undertaken in allergy clinics throughout Mexico. Ratios of SPT positivity were calculated for individual allergens, per climatic zone and nation-wide. Per allergen group the most important allergens were identified. Statistically significant differences between zones and the nation-wide data were tested with Pearson's Chi-squares test.

RESULTS

4169 skin test charts were recollected. The most important allergens causing sensitisation were very similar in different zones, despite climate variation. The allergen with highest ratio of SPT positivity was Dermatophagoides pteronyssinus (51%), with trees (Ash-27%, Alder-22%, Oak19%), and Bermuda grass (26%) as second and third. In the hot zones (humid and dry) Aspergillus was statistically significant more frequently than in more temperate zones. Cockroaches thrive in big cities and humid zones and Mesquite and Poplar in dry zones. Weeds are less important.

CONCLUSION

Mexico has its own SPT sensitisation pattern, which is different from America and Europe. A structured chart-review of SPT results is able to show this and might be a tool for allergists in other countries.

Characteristics of patients with respiratory allergy in France and factors influencing immunotherapy prescription: a prospective observational study (REALIS)

To describe the sensitization profile of respiratory allergies in France, identifying factors influencing the prescription of allergen immunotherapy (AIT) [Transversal phase (T)], and assess treatment efficacy, tolerability, compliance and satisfaction [Longitudinal phase (L)]. French allergists (600) and pneumo-allergists (600) were offered participation and asked to recruit the first 20 new patients with allergic rhinitis (AR) and/or asthma, consulting for a first time allergy check-up with skin prick-test (T), and 5 patients sensitized to pollens (skin test and/or specific IgE) for whom SLIT with pollens was prescribed (L). In the T phase, 2,714 patients were recruited by 169 specialists, mostly allergists (76.5%). The majority (98%) suffered from AR, alone (57.7%) or with asthma (40.3%) and 80.3% suffered from moderate-to-severe rhinitis, mostly persistent (65.8%). Asthma, when present, was mostly intermittent (63.7%) or mild persistent (20.1%). Sensitization to house dust mites was the most common (64.5%), followed by grass pollens (61.5%), tree pollens (41.6%) and cat danders (30.5%). Poly-sensitization was seen in 73.6% of patients. AIT, mostly sublingual, was recommended in 55.6% of the patients, mostly (78.1%) because of insufficient control with symptomatic treatments. The overall impact of symptoms on QOL, positive skin test to grass pollens, ocular pruritus and/or nasal obstruction and moderate-to-severe rhinitis were significant predictors of SLIT prescription. Poly-sensitization or concomitant asthma were not seen as deterrents. Most patients consulting a specialist for allergy testing suffer from moderate-to-severe rhinitis. Treatment in current practice includes immunotherapy in half of the patients, and follows ARIA recommendations.