Risk factors for atopic dermatitis in southern Puerto Rico

BACKGROUND: Little is known about the risk factors and exposures to aeroallergens in subjects with atopic dermatitis (AD) in Southern Puerto Rico. The objective was to determine the prevalence of skin reactions to aeroallergens and to analyze self-reported risk factors in AD patients and a nonallergic control population. METHODS: A cross-sectional study was conducted which included 726 AD patients and 313 nonallergic control subjects. Skin tests were conducted and a questionnaire was self-applied to all participants. RESULTS: Seventy six percent of the AD patients showed at least one positive skin reactions to aeroallergens. Of these, half had positive skin reactions to dust mites, and one third to Periplaneta americana. A low prevalence of positive skin reactions to dog, cat, plant and fungal allergens was detected. Co-sensitivitity between mites and cockroaches was 30%. The maximum skin reactivity to mites was at 10-19 years of age declining thereafter while skin reactivity to dogs, and plants increased with age. No significant differences in the prevalence of skin reactions was observed between the male and female AD population. CONCLUSIONS. Of the aeroallergens tested, those derived from dust mites are the most frequent sensitizing agents in the AD patients. Data also showed that the mites B. tropicalis and E. maynei are also important sources of sensitization. Our study show that young patients specially those between the age of 10-19 age group are the most allergic. Being female, or having an asthmatic father are significant risk factors associated with allergen sensitivity in the AD population.

Alfa 1 antitrypsin and protease levels in Puerto Rican asthmatics: a pilot study

A cross-sectional pilot study was conducted on a population of 119 asthmatics who had been recruited from the Emergency Room Department of a major hospital in Ponce, Puerto Rico. The purpose of the study was to determine the frequency of the MM, MS, and SS a-i-antiprotease variants. Also, we analyzed the serum levels of the alpha-1-antiprotease inhibitor, quantified the levels of serine proteases in homes of the asthmatic volunteers, and determined whether environmental levels of proteases, regardless of their sources, had any association with either asthma symptoms or alpha-1-antiprotease inhibitor phenotypes. Our results do not support the role of the alpha-1-antiprotease as a risk factor for asthma in the study population as previously reported. Patients who had visited the ED due to asthma on 3 or more occasions had significantly higher trypsin levels than those who had done so 2 or fewer times. Of those asthmatic patients who had daily symptoms, 40had been exposed to high levels of elastase, and 33.3to trypsin. Similarly, 52.9of the patients with 2 or more hospitalizations a year had been exposed to high elastase levels, and 40.5of asthma patients who had nocturnal asthma more than 3 times a week had been exposed to high levels of elastase.

Immunoblot analysis and comparative IgE responses of atopic patients to extracts of the domestic mite Blomia tropicalis

BACKGROUND: The domestic mite Blomia tropicalis is found in subtropical and tropical environments, and its clinical importance as a sensitizing agent in allergic disease is widely accepted. OBJECTIVE: To investigate the IgE reactivity to allergens present in extracts of the domestic mite B. tropicalis, and compare the IgE responses to these allergens by asthmatics, patients with atopic dermatitis and allergic rhinitis, as well as nonatopic controls. METHODS: Extracts from B. tropicalis were used for skin tests. The B. tropicalis specific IgE in the serum were measured using the FAST Plus Test and immunoblot analysis. RESULTS: A total of 199 volunteers participated in the study. The data show that 18 out of 29 polypeptide bands present in extracts of this mite species were recognized by the allergic and control sera. Of these allergens, four showed a high IgE binding frequency and had relative molecular weights of 104, 80, 68 and 14 kDa. The 14 kDa allergen demonstrated the highest IgE binding frequency. CONCLUSION: Sera from atopic patients reacted to more allergens than sera from patients controls. Extracts from pure bodies of B. tropicalis contain one immunodominant and three important allergens. A common characteristic between all of the sera tested was the high degree of serum IgE reactivity observed to the 14 kDa allergen.

Identification of the domestic mite fauna of Puerto Rico

This study was conducted to identify the domestic mite fauna of Puerto Rico. A total of 57 dust samples were collected from mattresses in homes of 11 cities on the Island. The analysis of the samples revealed that 73.70 percent of the mattress samples had at least one mite species. The identified species include: Dermatophagoides pteronyssinus (45.6 percent5), Blomia tropicalis (31.6 percent), Cheyletus sp. (19.3 percent), Dermatophagoides farinae (17.5 percent), Euroglyphus maynei (5.3 percent), Dermatophagoides sibonei (1.8 percent, Dermatophagoides sp. (1.8percent), Suidasia melanensis (1.8 percent) and mite species that were not identified (5.3 percent). Differences in the geographical distribution of mites showed that only Blomia tropicalis is more frequently in the northern (43 percent) than in the southern region (19 percent) of Puerto Rico (OR 3.36, p, 0.046). This finding can be explained by the fact that in the northern region the relative humidity is significantly higher that in the southern region (p < 0.001). No significant differences were observed for other species or in the total mite counts between the northern and southern regions. The small sample size of this study may explain the lack significance for some of the differences found. Nevertheless, our results indicate that the domestic mite fauna is composed of several clinically important species, their numbers are high enough to be considered in the sensitizing levels, and the diversity of these species is comparable to other observations in the Caribbean areas, and in the southern states in the continental US. Based upon our results, we recommend that when performing the skin test in Puerto Rico, extracts from the identified local domestic mite species be included in the allergen panel. This may prove useful in the aid for the diagnosis and management of atopic conditions

An estimate of the prevalence, severity and seasonality of asthma in visitors to a Ponce shopping center

To have an estimate of the prevalence of asthma in southern Puerto Rico, a cross-sectional study of a convenience sample of three thousand volunteers from southern Puerto Rico was conducted in a shopping center. Individuals were considered asthmatics when they indicated that had consulted their physicians during the previous 12 months for asthma, shortness of breath, accompanied wheezing, and medications had improved their condition. The crude point prevalence of asthma was 17.5 per 100 interviewees. The median age of the asthmatic population was 18 years while in the non-asthmatic it was 26 years of age (p < 0.0001). Males were 22 percent more likely to be asthmatics than females (p = 0.047). Twenty-six percent of the asthmatics reported hospitalizations at least one time, and 56 percent had received medical attention in emergency rooms due to asthma exacerbations. Analysis of the data strongly suggests that the asthma prevalence in southern Puerto Rico may be higher than in other parts of the United States and the rest of the world. This indicates that asthma probably is an important public health problem in the southern Puerto Rico and possibly, in the island

A comparison of albuterol solution nebulized versus albuterol powder given by breath activated metered dose inhaler

The goal of the present study was to compare the efficacy of nebulized vs powdered albuterol in patients with exacerbated bronchial asthma who required hospitalization. From January to May 1990 known asthmatics admitted with acute exacerbation were included by established criteria. Two groups were randomized. Group I for Albuterol powder 200 micrograms inhaled q 4 hours. Group II with Albuterol nebulized solution 2.5 mg inhaled q 4 hrs. Force Vital Capacity and Force Expiratory Volume in one second were measured with a pressure differential transducer upon admission, 30 minutes and 24-hours following therapies. Absolute FEV1 improvement was calculated. Statistical analysis was performed using student's T-Test and Fisher's exact Test with significance established at p > 0.01. Fifteen patients enrolled in both groups, two patients of group I were excluded from the statistic analysis due to refusal to continue with the therapy. Both groups were comparable with respect to sex, asthma exacerbations/year, smoking history and hospital length of stay. FVC and FEV1 were comparable also. In contrast, there were significant difference when the absolute improvement were compared. The mean +/- SE for FEV1 absolute improvement at the first 30 min was 0.42 +/- 0.08 lts for the Group I versus 0.65 +/- 0.6 lts in the Group II. In the next 24 hours, Group I was 0.16 +/- 0.2 lts versus 0.30 +/- 0.7 lts in Group II (p > .01). We conclude that although the dose equivalence of both delivery systems have not been established in our study, the nebulized solution was more effective during the first 24 hours of hospitalization than the dry powder