Clinical Features and Disease Management in Adult Patients With Atopic Dermatitis Receiving Care at Reference Hospitals in Brazil: the ADAPT Study.

BACKGROUND: Atopic dermatitis is a chronic inflammatory skin disease with a prevalence of 0.02% to 8.1% in adults. Adult patients with moderate-to-severe atopic dermatitis are affected by frequent relapses and a significant disease burden. Objective: To determine the clinical, immunological, and therapeutic profile of Brazilian adults with atopic dermatitis. METHODS: A multicenter, observational, retrospective, descriptive registry-based study was conducted at reference hospitals between December 2016 and October 2017. The data collected were demographics, personal and family history of atopic diseases, clinical manifestations, laboratory tests, disease severity and management. RESULTS: Of the 187 patients included in the analysis, 56.1% were female and 71.7% were White, with a mean age of 24.7 years. Mean follow-up was 9 years. Asthma or other allergic diseases were reported by 80.2% of patients. The main comorbidity was hypertension (10.2%), and common disease manifestations included pruritus and erythema. Lesions generally affected flexural and nonflexural areas, with typical morphology. Around 83% of patients had moderate-to-severe disease, and 8.6% reported at least 1 hospitalization. Most patients received topical and/or systemic pharmacological therapies, including omalizumab (5.9%); 4.3% received phototherapy. Moreover, 66.8% of patients received adjuvant therapy, and 79.1% changed or discontinued treatment for atopic dermatitis due to remission (46.5%), poor effectiveness (33.7%), or lack of adherence (12.9%). Most patients presented characteristics of type 2 inflammation, with immunoglobulin E levels above 100 IU/mL (94.4%) and peripheral blood eosinophils above 5% (55.9%). CONCLUSION: Brazilian adult patients with severe atopic dermatitis need treatment to efficiently control the disease and improve quality of life.

Clinical Features and Disease Management in Adult Patients With Atopic Dermatitis Receiving Care at Reference Hospitals in Brazil: the ADAPT Study

Background: Atopic dermatitis is a chronic inflammatory skin disease with a prevalence of 0.02% to 8.1% in adults. Adult patients with moderate-to-severe atopic dermatitis are affected by frequent relapses and a significant disease burden. Objective: To determine the clinical, immunological, and therapeutic profile of Brazilian adults with atopic dermatitis. Methods: A multicenter, observational, retrospective, descriptive registry-based study was conducted at reference hospitals between December 2016 and October 2017. The data collected were demographics, personal and family history of atopic diseases, clinical manifestations, laboratory tests, disease severity and management. Results: Of the 187 patients included in the analysis, 56.1% were female and 71.7% were White, with a mean age of 24.7 years. Mean follow-up was 9 years. Asthma or other allergic diseases were reported by 80.2% of patients. The main comorbidity was hypertension (10.2%), and common disease manifestations included pruritus and erythema. Lesions generally affected flexural and nonflexural areas, with typical morphology. Around 83% of patients had moderate-to-severe disease, and 8.6% reported at least 1 hospitalization. Most patients received topical and/or systemic pharmacological therapies, including omalizumab (5.9%); 4.3% received phototherapy. Moreover, 66.8% of patients received adjuvant therapy, and 79.1% changed or discontinued treatment for atopic dermatitis due to remission (46.5%), poor effectiveness (33.7%), or lack of adherence (12.9%). Most patients presented characteristics of type 2 inflammation, with immunoglobulin E levels above 100 IU/mL (94.4%) and peripheral blood eosinophils above 5% (55.9%). Conclusion: Brazilian adult patients with severe atopic dermatitis need treatment to efficiently control the disease and improve quality of life (AU)

Gene mapping strategy for Alu elements rearrangements: Detection of new large deletions in the SERPING1 gene causing hereditary angioedema in Brazilian families.

BACKGROUND: Hereditary angioedema (HAE) is a rare genetic disorder mainly caused by mutations in the SERPING1 gene, determining a deficit of C1 inhibitor (C1-INH). In approximately 10% of the cases, HAE with C1-INH deficiency (C1-INH-HAE) is caused by large gene rearrangements, which are not detected by Sanger sequencing. Here we present the exon quantification technique (EQT), a molecular diagnostic test for the detection of large genetic rearrangements in SERPING1, mapping the exact size and location of the deletion caused by the recombination of Alu elements. EQT analysis was performed on total DNA extracted from blood of patients belonging to two Brazilian families with a medical history of HAE, low plasma levels of C4 and C1-INH and no pathogenic alteration in SERPING1 analyzed by Sanger sequencing. RESULTS: Two large deletions were found, one of 1356 pb and one of 1804 pb, which resulted from recombination of two Alu elements present in introns 3 and 4 of the gene. CONCLUSION: These results showed that the EQT could be used as a simple, rapid, and efficient diagnosis test for analysis of large deletions and insertions involving SERPING1, otherwise not detected by Sanger sequencing, serving as a support technique for molecular diagnosis of HAE.

Allergic sensitization to laboratory animals is more associated with asthma, rhinitis, and skin symptoms than sensitization to common allergens.

BACKGROUND: Workers exposed to laboratory animals have a high risk of developing laboratory animal allergy (LAA). Atopy seems to be the main risk factor for LAA. We hypothesized that occupational sensitization is a better predictor for the development of asthma, rhinitis, and bronchial hyperresponsiveness (BHR) than common sensitization. OBJECTIVE: To investigate the association between occupational sensitization to laboratory animals and clinical outcomes. METHODS: This was a cross-sectional study performed at two universities on students and employees dealing with small rodents. The subjects were allocated in groups: non-sensitized, common sensitization, or occupational sensitization, according to the results of the skin prick test (SPT). All subjects answered a questionnaire about animal exposures, symptoms, allergic diseases, and underwent spirometry and bronchial challenge test with mannitol. Multivariate analysis was performed using Poisson regression to estimate the prevalence ratio (PR). RESULTS: Data from 453 volunteers were analysed. Non-sensitized group comprised 237 subjects; common sensitization group, 142 subjects; and occupational sensitization group, 74 subjects. Occupational sensitization was associated with greater risk for all outcomes studied. When the common sensitization group was reference, skin symptoms had PR of 1.36, 95% confidence interval (CI): 1.01-1.85; wheezing had PR of 1.75, CI 95%: 1.21-2.53; rhinitis had PR of 1.25, 95%: 1.11-1.40; nocturnal dyspnoea had PR of 2.40, 95% CI: 1.31-4.40; bronchial hyperresponsiveness (BHR) had PR of 2.47, 95% CI: 1.50-4.09; and confirmed asthma had PR of 2.65, 95% CI: 1.45-4.85. In addition, the overlap of asthma, rhinitis, and skin symptoms in a same subject was significantly more prevalent in the occupational sensitization group, 16.2% versus 4.9% in the common sensitization group. CONCLUSION AND CLINICAL RELEVANCE: Occupational sensitization is associated with allergic symptoms and respiratory diseases. SPT with occupational allergens along with other parameters may contribute to detection of risk for allergic and respiratory diseases associated with exposure to laboratory animals.

Requirement of MyD88 and Fas pathways for the efficacy of allergen-free immunotherapy.

BACKGROUND: We have shown that mycobacterial antigens and CpG oligodeoxynucleotides downmodulate airway allergic inflammation by mechanisms dependent on T-cell activation. Here, we investigated the participation of the innate response, particularly the role of MyD88 adaptor, and Fas molecules in the effectiveness of DNA-HSP65 or CpG/culture filtrated proteins (CFP) immunotherapy. METHODS: Mice sensitized and challenged with Der p 1 allergen were treated with DNA-HSP65, CpG/CFP, or with adoptively transferred cells from immunized mice. The treatment efficacy was assessed by evaluating eosinophil recruitment, antibody, and cytokine production. RESULTS: In addition to downregulating the Th2 response, DNA-HSP65 and CpG/CFP promoted IL-10 and IFN-γ production. Adoptive transfer of cells from mice immunized with DNA-HSP65 or CpG/CFP to allergic recipients downmodulated the allergic response. Notably, transfer of cells from DNA-HSP65- or CpG/CFP-immunized MyD88(-/-) mice failed to reduce allergy. Additionally, for effective reduction of allergy by cells from CpG/CFP-immunized mice, Fas molecules were required. Although DNA-HSP65 or CpG/CFP immunization stimulated antigen-specific production of IFN-γ and IL-10, the effect of DNA-HSP65 was associated with IL-10 while CpG/CFP was associated with IFN-γ. Moreover, after stimulation with mycobacterial antigens plus Der p 1 allergen, cells from mite-allergic patients with asthma exhibited similar patterns of cytokine production as those found in the lung of treated mice. CONCLUSIONS: This study provides new insights on the mechanisms of allergen-free immunotherapy by showing that both DNA-HSP65 and CpG/CFP downregulated house dust mite-induced allergic airway inflammation via distinct pathways that involve not only induction of mycobacterial-specific adaptive responses but also signaling via MyD88 and Fas molecules.

A single nucleotide deletion at the C1 inhibitor gene as the cause of hereditary angioedema: insights from a Brazilian family.

BACKGROUND: Hereditary angioedema is an autosomal dominant disease characterized by episodes of subcutaneous and submucosal edema. It is caused by deficiency of the C1 inhibitor protein, leading to elevated levels of bradykinin. More than 200 mutations in C1 inhibitor gene have been reported. The aim of this study was to analyze clinical features of a large family with an index case of hereditary angioedema and to determine the disease-causing mutation in this family. METHODS: Family pedigree was constructed with 275 individuals distributed in five generations. One hundred and sixty-five subjects were interviewed and investigated for mutation at the C1 inhibitor gene. Subjects reporting a history of recurrent episodes of angioedema and/or abdominal pain attacks underwent evaluation for hereditary angioedema. RESULTS: We have identified a novel mutation at the C1 inhibitor gene, c.351delC, which is a single-nucleotide deletion of a cytosine on exon 3, resulting in frameshift with premature stop codon. Sequencing analysis of the hypothetical truncated C1 inhibitor protein allowed us to conclude that, if transcription occurs, this protein has no biological activity. Twenty-eight members of the family fulfilled diagnostic criteria for hereditary angioedema and all of them presented the c.351delC mutation. Variation in clinical presentation and severity of disease was observed among these patients. One hundred and thirty-seven subjects without hereditary angioedema did not have the c.351delC mutation. CONCLUSION: The present study provides definitive evidence to link a novel genetic mutation to the development of hereditary angioedema in patients from a Brazilian family.

Sensitisation to aeroallergens in Brazilian adolescents living at the periphery of large subtropical urban centres.

OBJECTIVES: To evaluate the sensitization to aeroallergens determined by skin prick test (SPT) in Brazilian adolescents, and to correlate its positivity with the diagnosis of asthma and/or rhinitis based on the written questionnaire (WQ) of ISAAC phase III study. PATIENTS AND METHODS: A total of 996 adolescents (387 boys) were selected by systematic samples. A standard allergen extracts panel (positive/negative control, D pteronyssinus [Dpt], P americana [Pa], B germanica [Bg], dog, cat, fungal and grass mix) was used and its positivity compared with positive responses to asthma, rhinitis or both. RESULTS: Positive SPT to at least one allergen was observed in 466 adolescents (46.8 %), with sensitisation to Dpt in 79.1 %. Positivity to more than one allergen occurred in 232 students (49.8 %). The frequency of positive SPTs was significantly higher among adolescents with asthma (OR = 2.16), rhinitis (OR = 1.69), and asthma and rhinitis (OR = 2.03). Positive SPT to four or more allergens were higher among asthmatics (OR = 2.6) and among adolescents with asthma and rhinitis (OR = 3). CONCLUSIONS: A high sensitisation rate to aeroallergens was observed, significantly higher among those with asthma, rhinitis or a combination of both, especially in multiple sensitisations.

Níveis séricos de proteína catiônica eosinofílica e contagem de eosinófilos em crianças enteroparasitadas,residentes em área de baixo nível sócio-econômico na cidade de Natal, RN, Brasil / Serum eosinophil cationic protein levels end eosinophil counting in children enteroparasited

A Proteína Catiônica Eosinofílica (ECP) foi purificada de células humanas, pela primeira vez, em 1971 e, após cinco anos, foi identificada como sendo uma proteína granular eosinofílica que possui uma potente toxicidade para uma variedade de helmintos, bactérias e outros microrganismos. O objetivo deste trabalho foi diagnosticar as infecções por enteroparasitas correlacionando com níveis séricos de proteína catiônica eosinofílica e eosinofilia. Foram estudadas 150 crianças de ambos os sexos, com idade variando entre 3 e 6 anos, residentes no mesmo bairro e frequentadoras de creche. A Infecção Parasitária foi investigada por Exames de fezes pelosMétodos de Hoffmann, Pons & Janer e o de Baermann-Morais. Os níveis séricos de proteína catiônica eosinofílica foram determinadospor Fluoroenzimaimunoensaio, utilizando o Kit Unicap (Pharmacia & Upjonh) e a contagem de eosinófilos realizada em esfregaço sanguíneo corado pelo Leishman. Das crianças estudadas 140 (93,3%) apresentaram infecção por enteroparasitas e 10 (6,7%) apresentaram ausência de ovos e larvasde helmintos e cistos de protozoários. Cento e quarenta e oito amostras de soro foram analisadas para determinar os níveis de proteína catiônica eosinofílica e os resultados obtidos mostraram que foi 45,45μg/L a mediana das concentrações observadas e que com relação aos níveis de ECP em crianças parasitadas e não parasitadas por helmintos observou-se que as crianças parasitadas apresentaramconcentrações (MD=52,20μg/L) significantemente mais elevadas do que as não parasitadas (MD=29,70μg/L) e que houve uma correlação positiva entre níveis séricos de ECP e eosinófilos ( p< 0,0001 e r= 0,57).

The eosinophil cationic protein was purified from human cells, for the fist time in 1971, after five years, it was identified as being a eosinophil granular protein that is potencially toxic for helminthics, bacteria and other microorganisms. The purpose of this study was to diagnose the enteroparasitics infections co-related to the serum levels of eosinophil cationic protein and eosinophilia. One hundred and fifty children form both sexes, ages varying from 3 to 6 years old who live in the same neighbourhood and go to the same nursery were observed. The parasitic infection was investigated by faecal examinations using the Hoffmann, Pons & Janer and Baermann-morais methods. The serum cationic protein levels were determined by fluorimmunassay using the unicap kit (Pharmacia & Upjohn) and the counting of eosinophis was made by Leishman- stained smears. From the studied children 140 (93,3%) were infected by enteroparasitics and 10 (6,7%) showed no signs of eggs, helminthics, larva,and protozoarios cysts. One hundred and light samples of serum were analysed to determine the levels of eosinophil cationis protein and the obtaind results have showed that 45,45 ìg/L was the overage of the studied concentrations and that the relationship between the levels of eosinophil cationic protein (ECP) in parasited and non-parasited children was that the parasited children showed significantly hight concentrations (MD=52,20ìg/L) than the non-parasited children (MD=29,70 ìg/L). The results also have showed that there was a positive correlation between the serum levels of ECP and eosinophis ( p<0,0001 and r = 0,57).

Skin test reactivity to natural and recombinant Blomia and Dermatophagoides spp. allergens among mite allergic patients in the UK.

BACKGROUND: Many asthmatics in tropical and subtropical areas have positive skin prick tests to both Dermatophagoides spp. and to the mite Blomia tropicalis. This may be due to recognition by IgE of cross-reactive allergens between the different mite species or because of sensitization to species-specific allergens. A 14-kDa Blomia tropicalis allergen, Blo t 5, has been cloned and shows 40% sequence homology with Der p 5. The aim of this study was to investigate reactivity to B. tropicalis in patients known to be sensitized to D. pteronyssinus and to assess allergenic activity and cross-reactivity of recombinant (r) Group 5 allergens amongst these patients, who live in the UK and who are not exposed to B. tropicalis in their homes. METHODS: Patients (n = 19) with asthma and/or rhinitis were selected based on clinical history and a positive skin prick test to D. pteronyssinus extract and were compared with non-allergic skin test negative controls (n = 10). IgE antibody responses to Blomia tropicalis, Dermatophagoides pteronyssinus, rDer p 5 and rBlo t 5 were compared by quantitative intradermal skin testing using serial 10-fold dilutions of each allergen. End point titre was the highest dilution giving an 8 x 8 mm wheal at 15 min. IgE antibodies to Blomia tropicalis, Dermatophagoides pteronyssinus, rDer p 5 and rBlo t 5 were measured using RAST, CAP and RIA, respectively. RESULTS: All 19 patients had positive skin tests to D. pteronyssinus at concentrations of 0.001 to 1 AU/ml and 10 were skin test positive to rDer p 5 at concentrations of 10-4 to 5 micro g/ml. Positive intradermal tests to Blomia tropicalis were seen in 12/19 patients at concentrations of 0.002 to 2 micro g/ml. However none of the patients had positive skin tests to rBlo t 5. Non-allergic controls were all skin test negative at the highest concentration of each allergen tested. All subjects had quantifiable specific IgE to D. pteronyssinus, but only two had IgE to B. tropicalis. IgE to Der p 5 was found in six patients, but no patients had IgE to Blo t 5. CONCLUSIONS: This study of patients naturally exposed to D. pteronyssinus but not to Blomia tropicalis, provides evidence for IgE mediated cross-reactivity between allergens produced by both mite species. The results suggest that the Group 5 allergens of D. pteronyssinus and B. tropicalis are species-specific.

Use of a chimeric ELISA to investigate immunoglobulin E antibody responses to Der p 1 and Der p 2 in mite-allergic patients with asthma, wheezing and/or rhinitis.

BACKGROUND: Sensitization to indoor allergens, particularly to dust mites, is a strong risk factor for asthma in children and adults. Assessment of sensitization is carried out using in vivo and in vitro tests to detect specific IgE antibodies. OBJECTIVE: To investigate IgE antibody responses to mites in patients with asthma, wheezing and/or rhinitis, using chimeric ELISA to measure specific IgE antibodies to mite allergens Der p 1 and Der p 2. METHODS: Specific IgE antibodies to Der p 1 and Der p 2 were quantified by chimeric ELISA, and compared with IgE to Dermatophagoides pteronyssinus (Dpt) measured using the CAP system (Pharmacia). A panel of sera from 212 patients with asthma, wheezing and/or rhinitis and 11 controls was analysed. RESULTS: There was a significant correlation between IgE to Dpt measured by CAP and IgE to Der p 1 (r = 0.81, P < 0.001), Der p 2 (r = 0.79, P < 0.001) and combined Der p 1 and Der p 2 (r = 0.86, P < 0.001). Seventy per cent of all patients had IgE to Dpt, and of those, 76.5% had IgE to Der p 1, 79.2% had IgE to Der p 2 and 83.1% had IgE to Der p 1 and Der p 2 combined. Considering the cut-off level of 2 IU/mL of IgE to either Der p 1 or Der p 2, the predictive value for a positive IgE to Dpt by CAP was greater than 95%. CONCLUSIONS: The chimeric ELISA allowed accurate quantification of IgE antibodies to Dpt allergens Der p 1 and Der p 2, and it could be useful for studying immune responses to mites in patients with asthma and/or rhinitis.

Allergic and immunologic parameters in patients with Fanconi's anemia.

BACKGROUND: Fanconi's anemia (FA) is a rare recessive chromosomal instability disorder, characterized by progressive bone marrow failure and congenital defects. Patients with FA present with recurrent infections, particularly those of the respiratory tract. OBJECTIVE: The aim of the present study was to evaluate whether patients with FA have altered antibody-mediated immune responses. METHODS: A group of 12 patients with FA, 5-32 years old (6 males) was studied. Serum levels of IgG, IgM, IgA and IgG subclasses, isohemagglutinin titers and specific IgG antibodies to poliovirus and measles were determined using standard methods. Immediate skin tests to common inhalant allergens were performed, and total and specific serum IgE was quantitated using a fluoroenzymatic assay (Uni-CAP, Pharmacia). Antipneumococcal antibodies were measured by ELISA before and 4-8 weeks after immunization with pneumococcal vaccine (Pneumo 23, Pasteur Mérieux Connaught). Responses to serotypes 1, 3, 5, 6B, 9V and 14, which are the most prevalent in our country, were studied. RESULTS: Ten patients had elevated IgE levels in sera, and 7 of them had detectable specific IgE and positive immediate skin tests. An inadequate response to pneumococcal vaccination was found in 2 of the 12 patients. Isohemagglutinin titers and levels of IgG, IgM, IgA and IgG subclasses and antipoliovirus and antimeasles antibodies were within the normal limits for age in all patients. Two patients had undetectable IgG4 levels (below 5 mg/dl). CONCLUSIONS: The results indicate that a proportion of patients with FA (2/12) in our study had inadequate responses to pneumococcal vaccination. No other significant abnormalities of the immune system were found in these patients.

International Study of Asthma and Allergies in Childhood: validation of the rhinitis symptom questionnaire and prevalence of rhinitis in schoolchildren in São Paulo, Brazil.

Written questionnaires (WQ) have been widely used in epidemiologic studies. In order to yield comparable results, they must be validated after translation to another language. The International Study of Asthma and Allergies in Childhood (ISAAC) WQ has been previously validated by a comprehensive study, but its validation in Brazil has not been performed. Our objectives were to validate the rhinitis component of the ISAAC's self-applicable WQ following its translation to Portuguese, and to determine the prevalence of rhinitis and related symptoms among Brazilian children living in the city of São Paulo. A group of 10 pediatricians and 10 pediatric allergists graded the questions from 0 to 2 and established a maximum score for each question. The WQ was answered by parents or guardians of children 6-7 years of age with rhinitis (R) (n = 27) and of control children of the same age without rhinitis (C) (n = 27). The WQ was also completed by adolescents 13-14 years of age with rhinitis (R) (n = 32) and without rhinitis (C) (n = 32). Half of these individuals answered the same WQ after 2-4 weeks, to ensure reproducibility. Cut-off scores of 4 and 3 were identified for the 6-7- and 13-14-year-old groups, respectively, as scores predictive of rhinitis. The prevalence of rhinitis was 28.8% in the group of 3005 children 6-7 years of age and 31.7% in the group of 3008 children 13-14 years of age, respectively. Using the global cut-off score, these prevalences were even higher, in the order of 34.7% and 40.7%, respectively. In conclusion, the rhinitis component of the ISAAC WQ was proven to be reproducible, adequate and able to discriminate children and adolescents with and without rhinitis, and revealed that the prevalence of rhinitis among Brazilian children living in the city of São Paulo was as high as the prevalence of rhinitis in other areas of the world.

A sensitive reverse ELISA for the measurement of specific IgE to Der p 2, a major Dermatophagoides pteronyssinus allergen.

BACKGROUND: Epidemiologic studies have shown that the presence of IgE antibodies to house dust mite and other indoor allergens is an important risk factor for asthma. OBJECTIVE: The aim of this study was to develop a reverse ELISA (rELISA) for measuring specific IgE to Der p 2, a major Dermatophagoides pteronyssinus (Dpt) allergen, as a potential tool for followup of allergen immunotherapy. METHODS: Recombinant Der p 2 allergen or a monoclonal antibody to Der p 2 was used to coat plates in conventional ELISA (cELISA) and rELISA, respectively. Sera from 48 asthmatic patients with positive skin prick test (SPT+) to D. pteronyssinus extract were analyzed for total IgE and specific IgE to Der p 2, and the results were compared with a group of 41 SPT asthmatic and 30 SPT- control subjects. RESULTS: The sensitivity of the two assays for Der p 2-specific IgE was 3.9 EU/mL and their specificities were confirmed by inhibition tests, in a dose-dependent manner. There was a significant positive correlation between cELISA and rELISA (r = 0.74; P < 0.0001). However, rELISA was more sensitive than was cELISA, regarding both the positive sera percentage (70.8% vs 52.1%) and the Der p 2-specific IgE levels (28.4 vs 4.5 EU/mL) in SPT+ asthmatic patients. CONCLUSIONS: rELISA has shown to be a sensitive and alternative method for measuring Der p 2-specific IgE without using radioactive techniques. Detection of specific IgE to major allergens and relevant peptides, and identification of B cell epitopes in allergens will provide valuable information for the design of allergen analogs and peptides for immunotherapy.

Cockroach allergens and asthma.

Asthma and allergy are the most common diseases associated with cockroach infestation of houses in the United States and other parts of the world. Sensitization and exposure to cockroach allergens is associated with increased asthma morbidity in the United States, especially among lower socioeconomic groups, including African American and Hispanic populations. Exposure to cockroach allergens in the first 3 months of life has been associated with repeated wheezing and asthma. The principal domestic cockroach species are Blattella germanica and Periplaneta americana. Both species produce several potent allergens, including Bla g 2 (inactive aspartic proteinase), Bla g 4 (calycin), Bla g 5 (glutathione-S-transferase), the group 1 cross-reactive allergens Bla g 1 and Per a 1, and tropomyosin. Structural homology between tropomyosins from cockroaches, mites, and shrimp may explain clinical cases of the oral allergy syndrome. The 3-dimensional structures of several cockroach allergens are known, and biologically active recombinant allergens have been produced in high-level expression vectors. The use of recombinant cockroach allergens should allow mechanisms of cockroach-induced asthma to be investigated and may lead to the development of new approaches to asthma treatment. Environmental allergen measurements of Bla g 1 and Bla g 2 have allowed exposure levels that cause allergic sensitization to be established. Abatement studies have shown that a sustained decrease in cockroach allergen levels is difficult but can be accomplished by professional application of insecticides, together with rigorous household cleaning. Cockroach asthma is an important public health problem that affects patients who are the least likely to be compliant with treatment with asthma medications or environmental control. Patient education, improvements in the housing stock, and improvements in environmental and immunologic treatment strategies are likely to be the most successful approaches to reduce the prevalence of cockroach-induced asthma.

Ecology and elimination of cockroaches and allergens in the home.

Cockroach infestations have been indicated as a major contributor to asthma throughout the world. Several studies have shown that large numbers of asthmatic patients are sensitized to cockroach allergens. Eliminating this pest from homes, schools, and public buildings involves a long-term commitment to a rational extermination process. This article covers the characteristics of the major cockroach species that invade homes, assesses the role of environmental exposure to cockroaches in asthma, and provides an intervention program for their extermination.