Prospective study of consecutive patch testing in patients with contact dermatitis using an adapted Latin American baseline series

Summary

Background. Contact dermatitis is characterized by pruritic skin lesions with high prevalence rates. Our objective is to describe the clinical and epidemiological characteristics of a population with suspected contact dermatitis who underwent to a patch testing using an adapted Latin American baseline series.Methods. Observational, descriptive, analytical clinical study with prospective data collection was performed. 208 participants who underwent patch testing using an adapted Latin American baseline series containing 40 allergens were analyzed. The prevalence of contact allergies was compared with data from the literature. Pearson's chi-square test was used for qualitative variables. Quantitative variables were compared using the Mann-Whitney U test. The significance of the regression parameters was tested using the Wald statistical test. Results. A total of 69.7% had one or more positive tests. Among those, 82.8% were women (OR 1.371; p = 0.398). The hands were the most commonly affected site at 43%. An occupational history was detected in 19.2%. The most common allergens were nickel sulfate (32.2%), sodium tetrachloropalladate (19.7%), fragrance mix I (15.4%), and methylisothiazolinone (13.5%). In multivariate logistic regression models, nickel was significantly related to female sex, as well as palladium. Fragrance mix I was related to a family history of allergy (p less than 0.05). Methylisothiazolinone was statistically significantly related to face and hand lesions. Conclusions. This study demonstrated a detailed profile of a population with suspected allergic contact dermatitis. Our patch test results, using an adapted Latin American baseline series, represent a significant update of this important diagnostic tool.

Spirometric values in elderly asthmatic patients are not influenced by obesity

BACKGROUND

Studies have suggested that asthma in obese individuals differs from the classic asthma phenotype, presenting as a disease that is more difficult to control.

OBJECTIVE

The objective of the present study was to determine whether obesity, age or a combination of the two are associated with worse spirometry parameters in patients with asthma.

METHODS

This was an observational cross-sectional study involving patients over 18 years of age who had been diagnosed with asthma (allergic or nonallergic). We evaluated the results of their spirometric tests. The patients were classified in accordance with two criteria: body mass index (BMI) and age. Based on their BMIs, the patients were divided into three groups: normal weight, overweight and obese. Patients were also separated into two categories by age: 18-59 years of age; and ≥ 60 years of age.

RESULTS

We evaluated 451 patients with asthma and their spirometry tests. In the present study, the pulmonary function parameters were negatively correlated with BMI and age (P < 0.05). We found that there was a statistically significant correlation between spirometric values and BMI among patients 18-59 years of age (P < 0.001), however, among patients over 60, we did not observe this negative association.

CONCLUSIONS AND CLINICAL RELEVANCE

The spirometric values decreased significantly in proportion to the increase of BMI and age in patients with asthma, especially among young adults. There was no negative correlation between BMI and FEV(1) in the group ≥ 60 years of age, suggesting that perhaps the time of disease is a major factor in the loss of lung function than weight gain in the elderly.

Human insulin allergy: four case reports

Insulin allergy was not uncommon in the past, but has lowered with the introduction of human recombinant insulin. Human recombinant insulin allergy is a rare condition, now reported in less than 1% of treated patients. However, it is a serious condition that requires an immediate allergological work-up. In this study, we describe 4 cases of IgE-mediated reaction to human recombinant insulin, emphasizing some practical aspects in diagnosis and treatment.

Allergic asthma in patients with common variable immunodeficiency

BACKGROUND

Many patients with common variable immunodeficiency (CVID) have a clinical history suggestive of allergic respiratory disease. However, in such individuals, the prevalence of asthma and the role of atopy have not been well established. The objective of this study was to evaluate pulmonary function and identify asthma in patients with CVID. We also investigated the role of IgE as a trigger of asthma in these patients.

METHODS

Sixty-two patients diagnosed with CVID underwent spirometry, as well as skin prick testing and in vitro determination of serum-specific IgE levels for aeroallergens, together with bronchial provocation with histamine and allergen.

RESULTS

The most common alteration identified through spirometry was obstructive lung disease, which was observed in 29 (47.5%) of the 62 patients evaluated. Eighteen (29.0%) of the 62 patients had a clinical history suggestive of allergic asthma. By the end of the study, asthma had been diagnosed in nine (14.5%) patients and atopy had been identified in six (9.7%). In addition, allergic asthma had been diagnosed in four patients (6.5% of the sample as a whole; 22.2% of the 18 patients with a clinical history suggestive of the diagnosis).

CONCLUSION

In this study, CVID patients testing negative for specific IgE antibodies and suspected of having allergic asthma presented a positive response to bronchial provocation tests with allergens. To our knowledge, this is the first such study. When CVID patients with a history suggestive of allergic asthma test negative on traditional tests, additional tests designed to identify allergic asthma might be conducted.