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The objective of this study was to determine whether sensitization to certain aeroallergens is associated with acute asthma in Cartagena, Colombia. Ninety-nine subjects with acute asthma and 100 controls evaluated for other reasons were studied at a local emergency room. Sensitization was established by specific IgE determinations. Statistically significant differences between asthmatic subjects and controls were found in the prevalence of specific IgE to Dermatophagoides pteronyssinus, 64.6% vs. 28% (p = 0.0001); to Dermatophagoides farinae, 74.7% vs. 40% (p = 0.0001); to Euroglyphus maynei, 68.7% vs. 22% (p = 0.0001); and to Blomia tropicalis, 54.5% vs. 17% (p = 0.0001). The odds ratios were 4.9; 4.4; 7.7 and 5.8, respectively. In contrast, there was no significant difference between subjects with asthma and controls in the prevalence of specific IgE to Alternaria tenuis: 4% vs. 1% (p = 0.35); to Paspalum notatum (Bahia grass): 28% vs. 19% (p = 0.16); to Periplaneta americana (American cockroach): 21% vs. 19% (p = 0.83); to Ambrosia artemisifolia (short ragweed): 12% vs. 23% (p = 0.11); and to cat epithelium: 5% vs. 1% (p = 0.17). The results suggest that sensitization to domestic mites in subjects who reside in this tropical city is associated with acute asthma that requires emergency room treatment.

Background: In tropical climates, sensitization to Bloma tropicalis and Dermatophagoides pteronyssinus is high and mainly directed to species-specific allergens. There is some cross-reactivity between extracts of these mites, probably due to the group 5 allergens that have high sequence homology., Objective and Methods: We used the radioallergosorbent test (RAST), RAST inhibition and immunoblotting inhibition experiments to investigate the cross-reactivity between the recombinant allergens BtM and Der p 5, expressed as glutathione S-transferase fusion proteins, to detect the epitopes involved and to analyze the importance of this cross-reactivity., Results: Seventy-nine percent of 48 patients sera were RAST positive to both recombinants, with a strong correlation (r = 0.8, p<0.0001). BtM inhibited 25 and 21.1% of IgE-binding to B. tropicalis and D. pteronyssinus extracts respectively and Der p 5 inhibited 22 and 24% of IgE-binding to D. pteronyssinus and B. tropicalis extracts. Furthermore, BtM inhibited 74.5% of IgE binding to Der p 5 and Der p 5 inhibited 72.4% of IgE-binding to BtM. RAST inhibition with BtM-derived synthetic peptides showed that peptide 4 (residues 35-50) and peptide 5 (residues 46-61) inhibited 37 and 16% of IgE-binding to BtM while peptides 5 and 2 (residues 14-30) were able to inhibit the IgE binding (32 and 28%, respectively) to Der p 5., Conclusion: There is cross-reactivity between BtM and Der p 5, which explains almost all the cross-reactivity between the two mite extracts. This cross-reactivity seems to be related to epitope(s) at the C-terminal segment of these allergens.

Background: Asthma mortality rates have increased in several industrialized countries during the past two decades. In Latin America, there have been reported only a few national studies of asthma mortality., Objective: To determine asthma mortality rates in Colombia from 1979 to 1994., Methods: Death certificates from the National Administrative Statistical Department of Colombia were collected and analyzed., Results: For the entire population we found increasing rates of asthma mortality from 2.15 in 1979 to 3.3 in 1985 followed by a decrease to 1.6 in 1994. Overall, the trend has been to decrease, with a variation coefficient of 1.09% by year. Age-adjusted rates of death from asthma, based on the population distribution of 1973, showed the same decreasing trend. Deaths from asthma were more frequent in subjects older than 35 years as compared with those younger than 5 years of age or the age group ranging from 5 to 34 years. For the latter, rates of death increased from 0.32 in 1980 to 0.37 in 1988, and fell to 0.20 in 1991. From 1992 to 1994 rates for 5 to 34 years of age were higher than previously, increasing to 0.9 in 1992 and decreasing to 0.6 in 1994. There was no significant variation in death rates between men and women. Sixty-two percent of deaths from asthma occurred at home, 31% at hospitals, and 6.7% in other places. Most asthma deaths were in urban areas., Conclusions: In contrast to that observed in industrialized countries, we found a decreasing trend in asthma mortality in Colombia. Rates of death from asthma, however, are still high in this country.

There are not enough data concerning asthma mortality in Latin America. The Latin American Society of Allergy and Immunology coordinated this project to provide reliable data for gaining knowledge about our present situation, which is a condition indispensable to changing it. The following countries participated in this study: Argentina, Brazil, Chile, Colombia, Costa Rica, Cuba, Mexico, Paraguay, Peru, Uruguay and Venezuela. A uniform protocol was designed in Santa Fe, Argentina. Asthma mortality rates were analyzed in accordance with two variables: age-adjusted rates (5-34) and total death rates. The total population studied was 107, 122, 529 inhabitants. The highest death rates were found in Uruguay and Mexico (5.63), and the lowest in Paraguay (0.8) and Colombia (1.35). Age-adjusted (5-34) rates were higher in Costa Rica (1.38) and lower in Chile (0.28). Regarding sex, the analysis of the information provided by seven countries showed a predominance of females (51.8%) over males (48.18%). In the southern Latin American countries such as Chile, Uruguay, Paraguay and Argentina, which have marked climatic differences, deaths occurred mainly in the winter. It is important to emphasize that, in most countries, deaths from asthma occurred at home: Chile (60.7%), Argentina (63.4%) and Paraguay (88%). However, in Uruguay, 58.6% occurred during hospitalization. Mortality rates from bronchial asthma are high in most of the Latin American countries studied, even though further studies are needed. Asthma is a serious global health problem. People of all ages in countries throughout the world are affected by this chronic airway disorder that can be severe and sometimes fatal. The health ministries of each country do not believe asthma is a significant issue. Therefore, we should provide them with sound epidemiological studies to convince them to change their attitude toward this disease.

To characterize the allergens of Blomia tropicalis, a cDNA library was constructed and screened with allergic sera from asthmatic patients. One clone, Bt6, was subcloned and sequenced. The nucleotide sequence of 934 bp length shows a 390-bp reading frame which encodes a 130-amino acid protein with a MW 14.8 kD. No potential glycosylation site was found in the predicted protein. The inferred amino acid sequence has no homology to known allergens. It has a cytosolic fatty acid-binding protein (FABP) signature at 5-22 amino acid residues, 42.3% identity with the Sm14-FABP of Schistosoma mansoni and 36% identity with FABPs from rat, mouse, bovine and human. The protein was expressed as a GST fusion protein and the purified GST-Bt6 used for dot blot, RAST and RAST inhibition assays. The frequency of IgE binding of allergic sera to Bt6 was low (11%) and usually weak. One positive serum did, however, show strong reactivity by RAST and dot blot and Bt6 could inhibit 60% of the IgE binding of this serum to the B. tropicalis extract. These data show that Bt6 encodes a mite FABP with allergenic properties, which are pronounced in some atopic subjects.

The purpose of this study was to establish seasonal levels of Der p 1, Der f 1 and D. pteronyssinus allergens in mattress and floor dust samples in the homes of 20 mite-allergic asthmatic patients in Cartagena, Colombia. Dust samples were collected using a portable vacuum cleaner once monthly for the same 12 months in all houses. The highest Der p 1 levels in mattress samples were detected in August (geometric mean = 109.49 ng/g) and represented a 2.2-times increase from the lowest level observed in November. Der f 1 was detected in only 3 mattresses, ranging from 90 ng to 1.6 micrograms per gram of dust. The highest levels were detected in February and March. The highest level of D. pteronyssinus allergens in mattress dust samples, quantitated by RAST-inhibition, was 8, 994 AU/g (80% inhibition); the lowest level detected was 150 AU/g (5% inhibition). Allergen levels were significantly higher in mattresses than in floor samples (p < 0.001). Overall, a Spearman rank correlation coefficient of 0.48, p < 0.001, was obtained between Der p 1 and D. pteronyssinus allergens. There was a good correlation between mite allergens and absolute humidity (r = 0.8, p = 0.007). Der p 1, Der f 1 and D. pteronyssinus allergen levels show minimal variations in this tropical environment. Allergens derived from various mite species must be considered when assessing mite allergen exposure in these environments.

Background: The mite species Blomia tropicalis is commonly found in tropical and subtropical regions, and it is an important source of allergen in the city of Cartagena, Columbia., Aim: The study was designed to determine seasonal allergen levels of B. tropicalis in homes of patients with asthma and mite allergy., Methods: Dust samples from mattresses and floors in 20 homes were collected on a monthly basis for 1 year. Outdoor temperature, relative humidity, and rainfall were recorded. RAST inhibition was performed on extracts of dust samples. Allergen levels were compared with variations in climate., Results: B. tropicalis allergens were detected in all mattress samples. More than 50% RAST inhibition was detected in 30% of mattress samples and in 4.3% of floor samples, reflecting a high concentration of allergen. Significant correlations were only found between allergen levels and absolute humidity., Conclusion: Levels of B. tropicalis allergen fluctuated minimally in Cartagena, Colombia.

Behavior ratings by parents, teachers, and classmates of physically abused fourth to sixth graders, identified from the New York City Maltreatment Register, and case-matched classroom controls, showed substantial concurrence among informants: Parents and teachers both rated significantly more behavioral disturbance in the abused children, and peers' ratings were significantly correlated with adults' ratings, especially those by teachers. Children's exposure to spouse or partner physical abuse, which had a substantial prevalence among both child-abusing and control families, reduced the difference in disturbance ratings between children who were themselves physically abused and those who were not. Overall, we conclude that physically abused children show pervasive behavioral disturbance, in that parents, teachers, and classmates all see higher levels of behavior problems and lower levels of socially desirable behavior in them compared to their nonmaltreated peers.

The prevalence of positive skin prick tests to the mite species Dermatophagoides pteronyssinus, D. farinae, Blomia tropicalis, Chortoglyphus arcuatus, Lepidoglyphus destructor and Aleuroglyphus ovatus was determined in 297 asthmatic adults and children living in seven cities of five Latin American countries. A standardized protocol and a common battery of extracts were used at each site. The mean wheal diameters were measured after 15 min, and those > or = 3 mm were considered positive. Sensitization to D. pteronyssinus varied from 60.7% in Cartagena to 91.2% in São Paulo; to D. farinae from 53.3% in Córdoba to 97.2% in Caracas; to A. ovatus from 26.6% in Bogotá to 71.2% in São Paulo; to B. tropicalis from 46.5% in Mexico City to 93.7% in São Paulo; to C. arcuatus from 33.3% in Mexico City to 75% in São Paulo; and to L. destructor from 30% in Mexico City to 76.2% in São Paulo. This study reported the results of skin test sensitivities in both children and adults. The studies from São Paulo and Córdoba were confined to children and thus could be compared; there was a significantly higher prevalence of cutaneous sensitivity to mite allergens in the children of São Paulo than in those of Córdoba (p < 0.001 for all mite species). Cutaneous sensitivity to mite allergens is very common in young and adult asthmatics in Latin America, in areas both at sea level and at high altitudes. Environmental control measures should be reinforced in the treatment of asthmatics in Latin America.

Sensitization to the domestic mites Blomia tropicalis, Chortoglyphus arcuatus, Lepidoglyphus destructor and Aleuroglyphus ovatus was investigated in 77 subjects with clinical symptoms of asthma and/or allergic rhinitis and a positive skin prick test (wheal > or = 3 mm) to Dermatophagoides pteronyssinus and/or D. farinae. Seventy patients were skin test-positive to D. pteronyssinus and 73 to D. farinae. Serum samples from 29 nonallergic, skin test-negative individuals were used as negative controls. Specific IgE was determined by RAST and the results expressed as the % of the total counts bound (% TCB). A positive result (> or = 1% TCB) to D. farinae was detected in 89.6% of subjects, to B. tropicalis in 80.5%, to D. pteronyssinus in 75.3%, to C. arcuatus in 71.4%, to A. ovatus in 68.8% and to L. destructor in 59.7%. None of the controls had a positive RAST to any of the mite species. Different IgE binding patterns were observed among these subjects, suggesting sensitization to unique as well as common allergens in the different mite species. Sensitization to Pyroglyphidae (D. pteronyssinus and D. farinae) and non-Pyroglyphidae mites (B. tropicalis, C. arcuatus, L. destructor and A. ovatus) is common among allergic individuals in Cartagena. Extracts of these mites may be needed for a more accurate diagnosis and effective treatment of respiratory diseases due to mite allergy in tropical environments.

Test-retest interviews examining recent sexual activity were administered to 27 severely ill psychiatric patients after stabilization. Three reports were judged to be questionable. For the 16 sexually active patients among the remaining 24, high test-retest reliability was found for number of sexual partners, frequency of episodes, and proportions of episodes involving vaginal intercourse and use of condoms. The interviews did not exacerbate psychiatric symptoms.

Four thousand subjects from Cartagena, Colombia were surveyed in order to establish the prevalence of asthma in this city. They were considered to have asthma when they had consulted their physicians for shortness of breath accompanied with wheezing during the last year and had received asthma medications. Point and cumulative prevalence were 8.8% and 12.2%, respectively. Seventy percent of the affected population was less than 15 years old. There were no significant differences in the prevalence of asthma between sexes. Forty-five percent of asthmatic subjects had family histories of asthma. The prevalence of rhinitis was 16.4% and 30.6% of the patients with asthma. The asthma prevalence of this study is high, indicating that this respiratory disease is a significant health problem in this tropical city.

It is known from historical records that the population of Cartagena (Colombia) is a mixture of caucasoids (Spaniards) and negroids (Africans) that is named mulattos. The present study was carried out to determine the distribution of HLA antigens in this population. A sample of 370 individuals was HLA serologically typed; 91 of them were typed for Complement alleles and 47 were DNA typed using PCR amplification and oligonucleotide probes for the HLA-DQA1 locus. The analysis of the allele and haplotype frequencies obtained, together with the genetic distances calculated with other populations, showed that most of the HLA genes of mulattos are from negroids and caucasoids. The Asian and Amerindian contribution is small, consistent with the historical and socioanthropological documentation. For example, A23, Aw34, Aw36 and Bw45, as well as DQA1*0101, DQA1*0301 and BfF have frequencies similar to that observed in negroids. In contrast, many significant differences were observed when comparing the antigen and allele frequencies of mulattos with that of Asians and Amerindians. Our results add evidence to the notion that the arrival of Spaniards in America 500 years ago established several racial mixtures. The HLA characterization of one of these, mulattos, will allow a better application of the HLA technology in the fields of basic research, organ transplantation and forensic medicine among this population.

Allergic asthma (AA) is a multifactorial disease in which the IgE hyperresponsiveness to mite allergens is determinant for its pathogenesis and clinical picture. We have reported previously that IgE responsiveness to mite allergens in AA patients is linked to HLA and possibly controlled by a dominant suppression (Is) gene of that region. The present population study was done to detect alleles involved in the genetic control of mite IgE response that accompanies AA, using polymerase chain reaction and oligonucleotide DNA typing of DP locus. Instead of finding any significant positive association with AA, in this study we found that the allele DPB1*0401 is present mainly in the nonallergic control population and strikingly absent in patients (p less than 0.008), suggesting that this gene could confer resistance to AA and other atopic diseases. Our results add more evidence regarding the existence of Is genes in the HLA region involved in the control of IgE immune response to environmental allergens. Furthermore, they suggest that genes of HLA are important genetic components involved in the etiology of AA.