Exacerbations Among Patients With Asthma Are Largely Dependent on the Presence of Multimorbidity

BACKGROUND AND OBJECTIVE

Comorbidities can influence asthma control and promote asthma exacerbations (AEs). However, the impact of multimorbidity in AEs, assessed based on long-term follow-up of patients with asthma of different degrees of severity, has received little attention in real-life conditions. To describe the epidemiological and clinical characteristics and predictors of AEs in patients who had presented at least 1 AE in the previous year in the MEchanism of Genesis and Evolution of Asthma (MEGA) cohort.

METHODS

The work-up included a detailed clinical examination, pulmonary function testing, fractional exhaled nitric oxide (FeNO), blood counts, induced sputum, skin prick-tests, asthma questionnaires, and assessment of multimorbidity. The number of moderate-severe AEs in the preceding year was registered for each patient.

RESULTS

The study population comprised 486 patients with asthma (23.7% mild, 35% moderate, 41.3% severe). Disease remained uncontrolled in 41.9%, and 47.3% presented ≥1 moderate-severe AE, with a mean (SD) annual exacerbation rate of 0.47 (0.91) vs 2.11 (2.82) in mild and severe asthma, respectively. Comorbidity was detected in 56.4% (66.6% among those with severe asthma). Bronchiectasis, chronic rhinosinusitis with nasal polyps, atopy, psychiatric illnesses, hyperlipidemia, and hypertension were significantly associated with AEs. No associations were found for FeNO, blood eosinophils, or total serum IgE. Sputum eosinophilia and a high-T2 inflammatory pattern were significantly associated with AEs. Multivariable regression analysis showed a significant association with asthma severity, uncontrolled disease, and low prebronchodilator FEV1/FVC.

CONCLUSION

Our study revealed a high frequency of AE in the MEGA cohort. This was strongly associated with multimorbidity, asthma severity, poor asthma control, airflow obstruction, higher sputum eosinophils, and a very high-T2 inflammatory pattern.

A case of self-improving collodion ichthyosis associated with a rare variant of the ALOX12B gene

Collodion baby is usually a manifestation of autosomal recessive congenital ichthyosis, a heterogeneous group of congenital hyperkeratotic genodermatoses with highly variable severity and genetic background. Herein, we report a case of self-improving collodion ichthyosis, a rare subtype of autosomal recessive congenital ichthyosis, characterized by an almost-complete spontaneous resolution of symptoms.

Clopidogrel hyper-response increases peripheral hemorrhagic complications without increasing intracranial complications in endovascular aneurysm treatments requiring dual antiplatelet therapy

Clinical significance of increased clopidogrel response measured by VerifyNow P2Y12 assay is unclear; management guidelines are lacking in the context of neuroendovascular intervention. Our objective was to assess whether increased clopidogrel response predicts complications from endovascular aneurysm treatment requiring dual antiplatelet therapy. A single-institution, 9-year retrospective study of patients undergoing endovascular treatments for ruptured and unruptured aneurysms requiring aspirin and clopidogrel was conducted. Patients were grouped according to preoperative platelet inhibition in response to clopidogrel measured by the VerifyNow P2Y12 assay (VNP; P2Y12 reactivity units, PRU). Demographic and clinical features were compared across groups. Hemorrhagic complication rates (intracranial, major extracranial, minor extracranial) and thromboembolic complications (in-stent stenosis, stroke/transient ischemic attack) were compared, controlling for potential confounders and multiple comparisons. Data were collected from 284 patients across 317 procedures. Pre-operative VNP assays identified 9 % Extreme Responders (PRU ≤ 15), 13 % Hyper-Responders (PRU 16-60), 62 % Therapeutic Responders (PRU 61-214), 16 % Hypo-Responders (PRU ≥ 215). Increased response to clopidogrel was associated with increased risk of any hemorrhagic complication (≤60 PRU vs > 60 PRU; 39 % vs 24 %, P = 0.050); all intracranial hemorrhages occurred in patients with PRU > 60. Thromboembolic complications were similar between therapeutic and subtherapeutic patients (<215 PRU vs ≥ 215 PRU; 15 % vs 16 %, P = 0.835). Increased preoperative clopidogrel response is associated with increased rate of extracranial hemorrhagic complications in endovascular aneurysm treatments. Hyper-responders (16-60 PRU) and Extreme Responders (≤15 PRU) were not associated with intracranial hemorrhagic or thrombotic complications. Hypo-responders who underwent adjustment of antiplatelet therapy and neurointerventions did not experience higher rates of complications.

Severe, Intolerable Fatigue Associated with Hyperresponse to Clopidogrel

OBJECTIVE

Clopidogrel is a commonly used antiplatelet agent for the prevention of thromboembolic complications following neuroendovascular procedures, but anecdotal data have raised concern for the possibility that clopidogrel may induce severe, intolerable fatigue. The purpose of this study is to systematically investigate this phenomenon.

METHODS

We performed a dual-institution, 9-year, retrospective study of patients undergoing clopidogrel therapy for neuroendovascular procedures. Patients were included only if their response to clopidogrel was assessed by platelet function testing using the VerifyNow P2Y₁₂ (VNP) assay. Hyperresponse to clopidogrel was defined as P2Y₁₂ reaction units ≤60. Patients were considered to have had clopidogrel-induced severe fatigue if the onset of symptoms followed the initiation of clopidogrel therapy; symptoms improved following a reduction in the dose of clopidogrel; and symptoms could not be attributed to any other medical explanation.

RESULTS

Data were collected on 349 patients. Five patients (1.4%) met criteria for clopidogrel-induced severe fatigue. All 5 patients were female, ages 39-68. VNP assessments obtained while patients were symptomatic revealed hyperresponse to clopidogrel (0-22 P2Y₁₂ reaction units). Symptoms improved in all 5 patients when the dose of clopidogrel was reduced by half. Notably, 30% of patients (n = 103) demonstrated a hyperresponse to clopidogrel on at least 1 VNP assessment, but 98 of these patients did not suffer from severe fatigue.

CONCLUSIONS

A syndrome of severe fatigue and other constitutional symptoms is a rare but clinically significant side effect of hyperresponse to clopidogrel in patients undergoing neuroendovasular intervention.

United States Medicolegal Progress and Innovation in Telemedicine in the Age of COVID-19: A Primer for Neurosurgeons

Telemedicine has received increased attention in recent years as a potential solution to expand clinical capability and patient access to care in many fields, including neurosurgery. Although patient and physician attitudes are rapidly shifting toward greater telemedicine use in light of the COVID-19 pandemic, there remains uncertainty about telemedicine's regulatory future. Despite growing evidence of telemedicine's utility, there remain a number of significant medicolegal barriers to its mass adoption and wider implementation. Herein, we examine recent progress in state and federal regulations in the United States governing telemedicine's implementation in quality of care, finance and billing, privacy and confidentiality, risk and liability, and geography and interstate licensure, with special attention to how these concern teleneurosurgical practice. We also review contemporary topics germane to the future of teleneurosurgery, including the continued expansion of reciprocity in interstate licensure, expanded coverage for homecare services for chronic conditions, expansion of Center for Medicare and Medicaid Services reimbursements, and protections of store-and-forward technologies. Additionally, we discuss recent successes in teleneurosurgery, stroke care, and rehabilitation as models for teleneurosurgical best practices. As telemedicine technology continues to mature and its expanse grows, neurosurgeons' familiarity with its benefits, limitations, and controversies will best allow for its successful adoption in our field to maximize patient care and outcomes.

Role of diesel exhaust particles in the induction of allergic asthma to low doses of soybean

INTRODUCTION

Exposure to environmental pollutants such as diesel exhaust particles (DEP) increases the risk of asthma and asthma exacerbation. However, the exact mechanisms inducing asthma to low doses of allergens remain poorly understood. The present study aimed to analyse the immunomodulatory effect of the inhalation of DEP in a mouse model exposed to non-asthmagenic doses of soybean hull extract (SHE).

MATERIAL AND METHODS

BALB/c ByJ mice were randomly divided into four experimental groups. Two groups received nasal instillations of saline and the other two groups received 3 mg ml-1 SHE during 5 days per week for 3 weeks. One group in each pair also received 150 μg of DEP in the same instillations 3 days per week. SHE-specific IgE levels, oxidative stress, leukocyte pattern and optical projection tomography (OPT) imaging studies were assessed.

RESULTS

Inhalation of SHE and/or DEP increased levels of H2O2 in BAL, while coexposure to SHE and DEP increased SHE-specific IgE levels in serum. Inhalation of SHE alone increased eosinophils, B cells, total and resident monocytes and decreased levels of NK cells, while inhalation of DEP increased neutrophils and decreased total monocytes. Regarding dendritic cells (DC), the inhalation of SHE and/or DEP increased the total population, while the inhalation of SHE alone increased Th2-related DCs (CD11b + Ly6C-) and decreased tolerogenic DCs (CD11b-Ly6C-). However, coexposure to SHE and DEP increased oxidative stress-sensitive DCs (CD11b-Ly6C+) and decreased Th1-related DCs (CD11b + Ly6C+). As regards macrophages, inhalation of SHE and DEP decreased total and alveolar populations. DEP deposition in lung tissue did not differ between groups.

CONCLUSION

Coexposure to DEP activates the asthmatic response to low doses of soy by triggering the immune response and oxidative stress.

Immunomodulatory effect of pigeon serum in an acute and chronic murine model of bird fanciers lung

INTRODUCTION

Since the immunopathological mechanisms of bird fancier's lung (BFL) are not well known, we created two models of the disease (acute and chronic BFL) to study and compare the pathways involved in its immunopathogenesis.

MATERIALS AND METHODS

C57BL/6 mice were used. Two intraperitoneal injections of 100 μL of commercial pigeon serum (PS) or saline (SAL) were administered with an interval of 48 h in between. Subsequently, intranasal instillations of 40 μL of PS or SAL were performed three days a week, for three weeks in the acute model (AC/PS) and for twelve weeks in the chronic model (CR/PS). Total lung capacity (TLC) was assessed. Pulmonary inflammation was evaluated in bronchoalveolar lavage (BAL), and total serum immunoglobulin (Ig) G was measured in serum samples 24 h, 7 days and 14 days after the last exposure. Histological studies of lungs were assessed.

RESULTS

A drop in TLC was observed in treated mice. This decrease was more marked in the CR/PS group (p < 0.001). Neutrophil and lymphocyte counts increased in both AC/PS and CR/PS groups (p < 0.01). The extent of airway inflammation was also examined in the histological analysis of the lungs, which showed predominant perivascular and peribronchiolar inflammation, with centrilobular oedema and subpleural inflammation in the AC/PS group. In the CR/PS group, the changes were greater, with increased levels of IL-5, IL-17F, IL-13 and IL-10 and decreased levels of IL-2.

CONCLUSIONS

Bronchial inflammation is present in acute and chronic models of HP following exposure to PS. Our results support the role of neutrophils and IL-17 in the development of the disease and an evolution towards a Th-2 immune response in chronic HP. These models may serve as a tool for future studies of the pathogenesis of HP.

Diesel exhausts particles: Their role in increasing the incidence of asthma. Reviewing the evidence of a causal link

Exposure to air pollutants has been correlated with an increase in the severity of asthma and in the exacerbation of pre-existing asthma. However, whether or not environmental pollution can cause asthma remains a controversial issue. The present review analyzes the current scientific evidence of the possible causal link between diesel exhaust particles (DEP), the solid fraction of the complex mixture of diesel exhaust, and asthma. The mechanisms that influence the expression and development of asthma are complex. In children prolonged exposure to pollutants such as DEPs may increase asthma prevalence. In adults, this causal relation is less clear, probably because of the heterogeneity of the studies carried out. There is also evidence of physiological mechanisms by which DEPs can cause asthma. The most frequently described interactions between cellular responses and DEP are the induction of pulmonary oxidative stress and inflammation and the activation of receptors of the bronchial epithelium such as toll-like receptors or increases in Th2 and Th17 cytokines, which generally orchestrate the asthmatic response. Others support indirect mechanisms through epigenetic changes, pulmonary microbiome modifications, or the interaction of DEP with environmental antigens to enhance their activity. However, in spite of this evidence, more studies are needed to assess the harmful effects of pollution - not only in the short term in the form of increases in the rate of exacerbations, but in the medium and long term as well, as a possible trigger of the disease.

Identification of Pen m 4 as a potential cause of occupational asthma to Gammarus shrimp

We present the case of a 34-year-old male patient employed for 8 years in a company manufacturing and packaging animal feed. The patient developed occupational asthma to dry Gammarus powder. The diagnosis was confirmed by specific bronchial provocation test. The determination of specific IgE antibodies was positive for Pen m 4, a sarcoplasmic calcium binding protein, with a level of 6.7 ISU-E. The sensitization to Pen m 4 described here may identify a new allergen causing occupational asthma in these workers.

Asbestos-related disease in upholsterers

Before its use was banned in developed countries, asbestos was widely applied in upholstery. However, the risk of asbestos diseases among upholsterers has only rarely been reported. In this case series, we present a first series of 6 workers employed in small workshops who developed several asbestos-related diseases, including pleural plaques, pleural fibrosis, and asbestosis. Exposures were intermittent and difficult to quantify, but lung asbestos content assessed by bronchoalveolar lavage was high in the 3 patients evaluated. In conclusion, upholstery work should be considered an at-risk occupation for developing asbestos-related diseases during the 20th century.

Expansion of a CD26low Effector TH Subset and Reduction in Circulating Levels of sCD26 in Stable Allergic Asthma in Adults

BACKGROUND AND OBJETIVE

The pathogenesis of asthma is dependent on the balance between regulatory and effector T cells, which display differential expression of CD25 and CD26. Therefore, alteration of circulating levels of sCD25 and sCD26 during allergic asthma could be conditioned by changes in leukocyte phenotype. Objectives: To analyze expression of CD25 and CD26 on T lymphocytes and their soluble derivatives (sCD25, sCD26) during stable phases of moderate-severe allergic asthma.

METHODS

Cross-sectional study with 2 adult cohorts of allergic asthmatics. Clinical, anthropometric, pulmonary, hematological, and biochemical parameters were measured. Phenotyping was performed with flow cytometry in both circulating and cultured leukocytes. Dipeptidyl peptidase 4 (DPP4) activity was assayed in culture supernatants.

RESULTS

In vitro studies revealed upregulation of CD26 on human T lymphocytes upon activation, especially under TH17-favoring conditions, and a correlation with soluble DPP4 activity (rs=0.641; P<.001). CD26 expression on lymphocytes was higher in asthmatics, while serum sCD26 was lower in women and patients. The latter finding could be associated with an expanded CD25low/CD26low/CD127low subset of effector CD4+ T cells in allergic asthma, with no changes in Treg percentages. However, women showed an increased Teff/Treg ratio, which could explain their greater susceptibility to asthma.

CONCLUSIONS

Allergic asthma causes an increment in CD25lowCD26low helper T cells detected in stable stages. These changes are mirrored in serum and should be considered in the light of the downmodulating role of CD26 in major chemokines related to the pathogenesis of asthma such as CCL11 (eotaxin), CCL5 (RANTES), and CXCL12a (SDF-1α).

Persistence of respiratory and inflammatory responses after dermal sensitization to persulfate salts in a mouse model of non-atopic asthma

Background

Exposure to ammonium persulfate (AP) has been reported to be the main cause of occupational asthma in hairdressers. The aim of this study is to assess how long the asthmatic response to AP can be induced after dermal sensitization in a mouse model.

Methods

BALB/c mice received dermal applications of AP or dimethylsulfoxide (DMSO) (control) on days 1 and 8. They then received a single nasal instillation (challenge) of AP or saline on days 15, 22, 29, 36, 45, 60 and 90. Respiratory responsiveness to methacholine was measured 24 h after the challenge using a non-specific methacholine provocation test. Pulmonary inflammation was analysed in bronchoalveolar lavage (BAL), and total serum immunoglobulin (Ig) E, IgG1 and IgG2a were measured in serum samples. Histological analysis of lung slides was performed.

Results

Mice dermally sensitized and intranasally challenged with AP showed respiratory responsiveness to methacholine as long as 45 days after initial sensitization, as well as increased percentage of neutrophils in BAL compared with the control group. At day 60, dermally sensitized mice still presented bronchial hyperresponsiveness, while the percentage of neutrophils returned to baseline levels similar to those of controls. Total serum IgE increased significantly on day 22 after dermal sensitization. Total serum IgG1 and IgG2a increased from 45 days after dermal sensitization and remained high at 90 days.

Conclusions

Both respiratory responsiveness to methacholine and airway inflammation responses decrease with increasing time between sensitization and challenge. Respiratory responsiveness to methacholine tends to persist longer than inflammation.

Changes in PH in exhaled breath condensate after specific bronchial challenge test in patients with chronic hypersensitivity pneumonitis: a prospective study

Background

The aim of this study was to investigate the influence of the specific inhalation challenge (SIC) on changes of pH values in exhaled breath condensate (EBC) in patients with hypersensitivity pneumonitis (HP).

Methods

A prospective study of 85 patients with suspected HP, of whom 63 were diagnosed with HP due to exposure to avian or fungal antigens. In all cases, EBC samples were collected before and after completion of the SIC and pH values were determined.

Results

Taken as a whole, patients with HP did not present changes in EBC pH after SIC. However, considering only patients with exposure to molds, those diagnosed with HP had a significantly more acid pH post-SIC than those with another diagnosis (p = 0.011). This fact is not observed in patients exposed to bird’s antigens. A ROC curve showed that a reduction in EBC pH of 0.3 units or more after SIC in patients diagnosed with HP due to exposure to molds had a sensitivity of 30 % (CI: 12.8 to 54.3 %) and a specificity of 100 % (CI: 65.5 to 100 %).

Conclusion

EBC pH may be useful in interpreting SIC results in patients with HP, especially in those patients exposed to molds. Further studies are now required to test the validity of these proposals.

Evolution of occupational asthma: does cessation of exposure really improve prognosis?

AIM

To assess the evolution of occupational asthma (OA) depending on whether the patient avoids or continues with exposure to the offending agent.

METHODS

Study in patients diagnosed with OA using a specific inhalation challenge. Patients underwent the following examinations on the same day: clinical interview, physical examination, forced spirometry, methacholine test and determination of total IgE. Clinical improvement, deterioration or no change were defined according to the changes seen on the GINA severity scale at the time of diagnosis.

RESULTS

Of the 73 patients finally included, 55 had totally ended exposure and 18 continued to be exposed at work. Clinical improvement was observed in 47% of those who had terminated exposure and in 22% of those who remained exposed; clinical deterioration was observed in 14% and 17% respectively (p = 0.805). Logistical regression analysis, including the type of agent and the persistence or avoidance of exposure among the variables, did not show any predictive factors of clinical evolution. Similarly, the changes in FEV1 and in bronchial hyperresponsiveness were not associated with the avoidance or continuation of exposure to the causative agent.

CONCLUSIONS

Avoiding exposure to the causative agent in patients with OA does not seem to improve prognosis in this disease. Despite these findings, there is insufficient evidence to recommend a change in current management guidelines.

[Determining asthma treatment in children by monitoring fractional exhaled nitric oxide, sputum eosinophils and leukotriene B₄]

Sputum eosinophils and exhaled fractional nitric oxide (FENO) are markers of airway inflammation in asthma. Cytokines, cysteinyl-leukotrienes and leukotriene B4 (LTB4) are responsible for this inflammation. The aim of this study is to determine the usefulness of these markers in monitoring asthma treatment in children. FENO, sputum eosinophils, and LTB4 in induced sputum were performed in 10 children (9-15 years old). These determinations were repeated four months later, after the beginning or an increase in the treatment. FENO values tended to decrease (P=.15), pulmonary function tended to improve (P=.10), and sputum eosinophils decreased (P=.003) compared to the first determination. There were no differences in LTB4 concentrations (P=.88). Sputum eosinophils seem to be more precise than FENO in the monitoring of inflammation in asthmatic children.

Work-related asthma: diagnosis and prognosis of immunological occupational asthma and work-exacerbated asthma

The incidence and prevalence of asthma are increasing. One reason for this trend is the rise in adult-onset asthma, especially occupational asthma, which is 1 of the 2 forms of work-related asthma. Occupational asthma is defined as asthma caused by agents that are present exclusively in the workplace. The presence of pre-existing asthma does not rule out the possibility of developing occupational asthma. A distinction has traditionally been made between immunological occupational asthma (whether IgE-mediated or not) and nonimmunological occupational asthma caused by irritants, the most characteristic example of which is reactive airway dysfunction syndrome. The other form of work-related asthma is known as work-exacerbated asthma, which affects persons with pre-existing or concurrent asthma that is worsened by work-related factors. It is important to differentiate between the 2 entities because their treatment, prognosis, and medical and social repercussions can differ widely. In this review, we discuss diagnostic methods, treatment, and avoidance/nonavoidance of the antigen in immunological occupational asthma and work-exacerbated asthma. Key words: Specific inhalation challenge. Peak expiratory flow. Workplace. Irritants.

Induced sputum cell count and cytokine profile in atopic and non-atopic children with asthma

BACKGROUND AND AIM

Sputum induction is a semi-invasive technique used to detect and monitor airway inflammation. In this study, the cell profile, and Th1 and Th2 cytokine levels in induced sputum of asthmatic and healthy children (HC) are compared.

METHODS

Sputum induction was performed in healthy and asthmatic children by inhalation of hypertonic saline solution. Differential cell count in the specimen obtained was carried out using optic microscopy. IFN-γ, IL-2, IL-10, IL-8, IL-6, IL-4, IL-5, IL-1β, TNF-α, and IL-12p70 levels were determined in sputum sample supernatants by flow cytometry.

RESULTS

Sputum induction was performed in 31 HC and 77 asthmatic children (60 atopic and 17 non-atopic asthma, NAA). Twenty-four samples were obtained in HC and 64 in patients. Median eosinophil count in atopic asthma (AA; 2%) was higher than in NAA (P = 0.02) or HC (P = 0.01). IL-4, IL-5, IFNγ, IL-2, and IL-12p70 concentrations were higher in AA than in NAA or HC. IL-8 was higher in asthmatic children (atopic and non-atopic) than in healthy ones. IL-10 was higher in the healthy group than in the AA group (P = 0.02).

CONCLUSIONS

As compared to HC, the inflammatory profile in induced sputum of children with asthma showed an increase in proinflammatory cytokines. Concentrations of IL-10, an anti-inflammatory cytokine, were lower in children with AA than in HC.

Bronchial inflammation and hyperresponsiveness in well controlled asthma

BACKGROUND

Little research has been devoted to the characteristics of bronchial inflammation in patients with stable, well controlled asthma.

OBJECTIVE

The aim of this study was to assess the degree and type of airway inflammation and to investigate the relationship between inflammation and bronchial hyperresponsiveness in patients with well controlled asthma.

METHODS

A cross-sectional study was conducted in 84 adult patients (43 men, mean age 43 years) with documented well controlled asthma. Induced sputum samples were obtained and cell types determined by differential cell count. Spirometry and methacholine challenge testing were performed. Asthma Control Questionnaire (ACQ) was used to assess symptoms. Patients were included if their ACQ score was < 0.75.

RESULTS

A total of 59 patients had persistent bronchial inflammation: 28 cases were considered eosinophilic, 28 neutrophilic, and 3 mixed. Median (range) percentage of eosinophils was 4% (0-64) in patients testing positive to methacholine challenge (n = 66) and 1% (0-3) in those testing negative (n = 18) (P = 0.003). A positive correlation was found between eosinophil percentage and the methacholine dose/response ratio (r = 0.477, P = 0.0001). The geometric mean (95% CI) of the methacholine PC20 was 1.74 mg/mL (1.04-2.93) in patients with eosinophilic inflammation and 4.14 mg/mL (2.5-6.84) in those with neutrophilic inflammation (P = 0.03).

CONCLUSIONS

Inflammation and bronchial hyperresponsiveness persist in most patients with well controlled asthma.

CLINICAL RELEVANCE

The study demonstrates that eosinophilic or neutrophilic inflammation persisted in most well controlled asthma patients despite the fact that their condition was controlled and therefore, measurement of bronchial inflammation seems essential to achieve proper asthma control.

Soy aeroallergens in thoracic fraction particles (PM10)

BACKGROUND

The aerodynamic diameter of biological particles determines their ability to penetrate the human respiratory system.

OBJECTIVE

To assess the content of allergens less than 10 pm in diameter in the particle fraction of airborne dust in order to improve control of exposure to harmful soybean aeroallergens.

METHODS

In this study, 98 pairs of particulate matter measuring less than 10 microm in diameter (PM10) and total suspended particulate (TSP) filters were collected in parallel and analyzed for soy aeroallergens by the inhibition enzyme-linked immunosorbent assay.

RESULTS

The median levels found were 6 and 22.5 U/m3 for PM10 and TSP filters, respectively. A good correlation was found between soy aeroallergen content in PM10 and TSP filters. The median proportion of soy aeroallergen content in PM10 filters versusTSP filters was 28.6%, and varied widely across different days.

CONCLUSIONS

Due to this wide variation between days, it seems that soy aeroallergen content in TSP filters is not a good surrogate of soy allergen content in PM10 filters. Further clinical studies should be conducted to assess differences in the health impact of soy allergen content in PM10 filters and TSP filters.

Utility of exhaled breath condensate pH for diagnosing occupational asthma

INTRODUCTION

The current reference standard method for diagnosing occupational asthma (OA) is specific inhalation challenge (SIC) with the suspected agent. The alternative method is serial peak expiratory flow (PEF) monitoring. Nevertheless, PEF does not have optimal sensitivity and specificity for this purpose. The aim of this study was to evaluate the utility of exhaled breath condensate (EBC) pH for the diagnosis of OA.

MATERIAL AND METHODS

A prospective study was performed in 37 subjects with suspected OA. Serial PEF monitoring was carried out for 2 weeks at work and for 2 weeks off work. At the end of each period, the EBC pH and the methacholine concentration resulting in a 20% FEV(1) decrease (PC20) were measured. SIC was subsequently performed. PEF graphs were interpreted visually by 3 experienced independent readers.

RESULTS

Seventeen patients tested positive with SIC. Receiver-operating characteristic curves showed that a decrease in EBC pH greater than 0.4 units during the period at work compared to the off-work period achieved the most satisfactory sensitivity (40%, CI 19.4-66.5) and specificity (90%, CI 66.9-98.2) for diagnosing OA. When EBC pH findings were added to PEF results, the diagnostic yield of PEF generally increased. Other test combinations (e.g. EBC pH plus PC20 or EBC pH plus PC20 plus PEF) did not improve diagnostic performance.

CONCLUSIONS

Acidification of EBC pH at work and adding the EBC pH measurement to PEF monitoring during periods at work and off work may be useful for improving the diagnosis of OA.

Prevalence of possible occupational asthma in hairdressers working in hair salons for women

BACKGROUND

The aim of this study was to determine the prevalence of possible occupational asthma (OA) in hairdressers.

METHODS

A telephone questionnaire (Q1) was administered to 1,334 individuals from a total of 1,875 hairdressers working in hair salons for women in Barcelona (response rate 71%) to identify those with respiratory symptoms. Multiple correspondence analysis showed 5 specific questions for assessing symptoms of asthma. Individuals who gave a positive response to 1 of these questions (n = 251) were given a second validated questionnaire (Q2) to identify those with suspected OA. OA was defined according to a classification tree based on the response to queries on nasal itching, daily symptoms throughout the week at work, nasal secretions, voice loss, wheezing, and sputum production as reported previously. Moreover, we calculated the prevalence of OA according to the conventional criteria of improvement and/or worsening of symptoms in relation to exposure at work and during off-work time on weekends and during vacations.

RESULTS

Asthma was present in 9.5% of hairdressers. From Q2 data, 72 were classified as having possible OA, yielding a prevalence of OA from 5.4 (72/1,334) to 7.8% according to the classification tree previously described. A prevalence from 4.6 (62/1,334) to 6.7% was obtained using conventional criteria. Rhinitis or dermatitis (OR 7.80), as well as exacerbation of symptoms at work and persistence of symptoms on weekends (OR 2.99) were associated with the development of OA.

CONCLUSIONS

Hairdressing employment can induce asthma. Episodes of rhinitis or dermatitis seem to be risk factors for the development of OA in this population.

Occupational asthma caused by metal arc welding of iron

Epidemiological studies have shown that exposure to welding fumes can be a cause of occupational asthma (OA), although the mechanisms implicated are unknown. We describe 3 patients (all men, mean age 42 years) with OA secondary to exposure to welding fumes generated during metal arc welding on iron. The exposure time ranged from 7 to 43 years and the time of the onset of symptoms following the start of exposure was 2-12 years. Patients were diagnosed by specific inhalation challenge (SIC). Environmental levels of Fe, Cd, Cu, Cr, Ni, NO2, NO, CO, and O3 produced during the SIC did not exceed threshold limit values. Samples of induced sputum were obtained before and after the SIC and showed an increase in neutrophils and concentrations of IL-8, TNF-α and TNF-β after the SIC. This study presents the first clinical findings reported in welders with OA, mainly working with iron. Neutrophilic inflammation seems to play a role in this disease.

Immunoquantitative measurement of soybean aeroallergen emissions at industrial sites

BACKGROUND

Asthma attacks and mortality due to inhalation of soybean antigens in Barcelona, Spain have been well documented. A new control scheme was adopted in the city to avoid the emission and dispersion of soybean dust into the atmosphere during unloading. We studied soybean allergen emission during unloading and at 3 industrial sites and compared the results obtained.

METHODS

Over a period of 31 months, 628 paired air samples from 3 plants (A, B, C) involved in soybean manipulation in Barcelona harbor were collected. Samples were analyzed by a radiometric competitive inhibition assay (RCIA) and the enzyme-linked immunosorbent assay (ELISA). A Bland-Altman plot was used to compare the soybean concentrations measured by each assay.

RESULTS

The median values for the 628 samples were 5535 U/m3 (range, 370-18,416,751) for the RCIA and 9955 U/m3 (range, 400-22,349,059) for the ELISA. Plant A had the lowest emission levels and the lowest Spearman rank correlation coefficient (0.409). The correlation coefficients were 0.747 and 0.794 for plants B and C. Soybean aeroallergen concentrations differed by plant. The highest variability in values was seen for plant A, which had the lowest allergen concentrations.

CONCLUSIONS

The competitive assays described are useful tools for the measurement of soybean allergen emission levels at industrial sites. These methods may be used to monitor unloading and the impact of environmental interventions.

Assessment of soy aeroallergen levels in different work environments

BACKGROUND

Airborne soybean hull proteins are known causes of asthma epidemics around harbours and soy processing plants. Soy flour dust proteins may cause occupational allergy in food and feed industries.

OBJECTIVE

To compare enzyme immunoassays (EIAs) for soy hull and soy flour aeroallergens, exposure assessment in various work environments.

METHODS

Airborne dust samples (n=324) from soy unloading and/or processing plants, the animal feed industry and pig stables were analysed by two soy flour assays: one assay for measuring complete soy hull proteins and two assays for measuring the purified low-molecular-weight (LMW) soy hull allergens.

RESULTS

Immunoblotting confirmed strong differences between antibody specificities and soy preparations. The results of the two soy flour assays and the assay for measuring complete soy hull proteins were highly correlated (r>0.85). The two LMW soy hull assays also showed a strong mutual correlation (r=0.91), but much less correlation with assays for measuring soy flour and complete soy hull. The levels of LMW soy hull proteins were the highest at sites of soybean unloading or processing, while soy flour levels were particularly high in the soy and animal feed industry.

CONCLUSIONS

The optimal EIA procedure for soy aeroallergen exposure assessment depends on the type of work environment and the local soy dust composition. Thus, the type of work environment should always be taken into account in future soy allergy studies in order to prevent a possible underestimation of the workers' actual risk of developing soy allergy.

An amplified sandwich EIA for the measurement of soy aeroallergens

BACKGROUND

Soy hull low-molecular-weight (SHLMW) allergens were responsible for the soy asthma epidemics in Barcelona, with one 7.5 kDa protein (Gly m 1) being the main IgE-binding component. The aims of this study were to develop a sensitive sandwich enzyme immunoassay (EIA) using rabbit polyclonal antibodies to measure low levels of SHLMW allergens, and to compare this method with the previously described human IgE EIA-inhibition technique.

METHODS

IgG was isolated from serum of rabbits immunized with a chromatographically purified SHLMW extract (SHLMWE). Antibody-binding profiles were compared with those of human IgE anti-soy protein antibodies by Western blot analysis. An amplified sandwich EIA was developed using the purified SHLMWE as a calibration standard. Results were expressed in nanograms per millilitre. To compare the two assays, 54 air samples were analysed by both methods.

RESULTS

SDS-PAGE of the SHLMWE revealed four bands of 6, 8, 15 and 17 kDa. Gly m 1 in the SHLMWE was identified by fingerprinting. The detection limit of the assay was 40 pg/mL. The two methods correlated well (r=0.89; P<0.001). The allergen concentration was detected in all 54 (100%) samples by the sandwich EIA but in only 37 (68.5%) by the EIA inhibition.

CONCLUSIONS

The amplified sandwich EIA for SHLMW components has a high sensitivity and appeared to be a useful tool for the measurement of airborne SHLMW allergens, even at relatively low concentrations. Moreover, the method uses rabbit antibodies at high dilutions and does not require human sera, with limited availability and quantitative and qualitative pool-to-pool variability.

Occupational asthma related to mouse allergen exposure and rhinoconjunctivitis due to collagenase inhalation in a laboratory technician

We describe the case of a 27-year-old patient working in a research laboratory, who developed occupational asthma to mouse proteins and presented symptoms of rhinoconjunctivitis caused by manipulation of collagenase. Specific inhalation challenge confirmed the diagnosis of occupational asthma to mouse proteins, whereas specific challenge with collagenase only evoked symptoms of rhinitis and conjunctivitis. SDS-PAGE and Western blot analysis for collagenase showed that the patient's IgE antibodies bound specifically to a protein with a molecular weight of 92 kDa. Hence, this was an unusual case of double sensitization. The sensitization to collagenase presented in this report may represent a new occupational disease in technicians working in medical or research laboratories.

Validation of specific inhalation challenge for the diagnosis of occupational asthma due to persulphate salts

BACKGROUND

The significant value of tests used to certify the diagnosis of occupational asthma due to persulphate salts remains uncertain.

AIMS

To validate the specific inhalation challenge (SIC) test for the diagnosis of occupational asthma.

METHODS

Eight patients with occupational asthma due to persulphate salts, eight patients with bronchial asthma who were never exposed to persulphate salts, and ten healthy subjects were studied. Clinical history taking, spirometry, bronchial challenge with methacholine, skin prick testing to common inhalant allergens and persulphate salts, total IgE levels, and SIC to potassium persulphate were carried out in all subjects. The SIC used increasing concentrations of potassium persulphate (5, 10, 15, and 30 g) mixed with 150 g of lactose. Patients tipped the mixture from one tray to another at a distance of 30 cm from the face for 10 minutes in a challenge booth.

RESULTS

The SIC was positive in all subjects with persulphate induced asthma and in one patient with bronchial asthma who had never been exposed to persulphate salts. Sensitivity was 100% (95% CI 67.6 to 100) and specificity was 87.5% (95% CI 52.9-97.8) when patients with occupational asthma due to persulphate salts were compared with those with bronchial asthma never exposed to persulphate salts.

CONCLUSIONS

SIC to persulphate salts performed according to the protocol described appears to be useful for the diagnosis of occupational asthma secondary to inhalation of this substance.

[Occupational asthma in food packers]

This report describes the case of a 26-year-old woman working in a fish-processing factory who developed bronchial asthma when transferred to the packing department. Various tests, including a specific bronchial challenge test, confirmed a diagnosis of occupational asthma. While polyvinyl chloride (PVC) appeared to be the causal agent in this case, the possible role of other etiological agents is also discussed. Although occupational asthma in food packers is rare, we nonetheless consider it important to recognize this type of asthma given the widespread use of PVC.

External auditory canal eccrine spiradenocarcinoma: a case report and review of literature

BACKGROUND

Eccrine spiradenocarcinoma is a rare dermal appendage carcinoma believed to arise from transformation of a long-standing benign spiradenoma. This tumor demonstrates highly malignant biologic behavior with a high recurrence rate, frequent lymph node metastases, and overall poor survival.

METHODS

We report the first case of eccrine spiradenocarcinoma arising in the external auditory canal. The management of this tumor, its histopathologic characteristics, and a review of literature are presented.

RESULTS

A literature review identified 17 cases of eccrine spiradenocarcinoma in the head and neck region. Local recurrence occurred in 58.8% of patients, with an average of 23 months from diagnosis. Lymph node metastasis occurred in 35.3%, with an average of 31 months from diagnosis. Other metastatic sites included skin, bone, and lung. Disease-specific mortality was 22.2%.

CONCLUSIONS

Eccrine spiradenocarcinoma is an aggressive tumor with a poor prognosis. Primary treatment should include wide local excision with or without regional lymphadenectomy. Isolated successful treatments have been documented with adjuvant hormonal manipulation, chemotherapy, and radiation therapy.

Sarcocystis spp infection in Philippine water buffaloes (Bubalus bubalis)

In a survey of sarcocysts in muscle tissues obtained from 142 water buffaloes, 65% of the carcasses had sarcocysts. Macroscopic and two forms of microscopic sarcocysts, the spindle-shaped or fusiform sarcocysts commonly occurring in the muscles of the esophagus, throat and limbs, and the globular to oval-shaped sarcocysts which were the dominant form in the diaphragm and cervical muscle tissues were noted. Ultrastructural analysis of macroscopic and microscopic sarcocysts and their cyst wall revealed two distinct species of Sarcocystis: the macroscopic species, Sarcocystis fusiformis which has been previously reported in Philippine carabaos possessing highly dendritic cauliflower-like projections emanating from the primary cyst wall, with annulated microfilaments and numerous electron dense granules: and the Sarcocystis levinei (Dissanaike and Kan, 1978) Huong, Dubey and Uggla. 1997 exhibiting a cyst wall with undulating and hair-like villar protrusions with expanded or dome-shaped base, intermediate finger-like, and distal tapering segments which at some points join to form conical tufts. Our findings represent the first report of S. levinei in the country supported with ultrastructural analysis of the sarcocysts and cyst wall, and likewise refute earlier published reports that all microscopic sarcocysts in Philippine carabaos are developing forms of the macroscopic species, S. fusiformis. Histopathological changes such as displacement and necrosis of the surrounding host muscle tissue were observed with macroscopic sarcocysts and histologically processed tissue samples containing microscopic fusiform sarcocysts. Necrotic myofibrils and mitochondria were evident in ultrathin sections.

Chemical monitoring and evaluation of the water quality of the Douro River at the Crestuma-Lever dam

Water taken from the Crestuma-Lever dam on the Douro River was evaluated considering the Portuguese Decree-law no. 236/98 of 1st August, 1998. This paper presents the metrological characteristics, validation of analytical methodologies and the data obtained from seasonal samplings. The test parameters selected are: temperature, pH, chloride, conductivity, carbon dioxide, alkalinity, hardness, oxidability, dissolved oxygen, BOD5, total suspended solids, sulfide, phosphate, silica, ammonium, nitrite, nitrate, sulfate, sodium, potassium, calcium, magnesium, iron, manganese, copper and zinc. From data analysis we can conclude that the water presented the following characteristics: a pH situated in the neutral zone; a median mineralization; a medium hardness; well oxygenated water; and a carbonate hardness exclusively due to bicarbonates. The temperature, pH, dissolved oxygen, ammonia, chlorides, sulfates, copper, zinc and BOD5 were compared with the legal limits presented in annexes XXI and I of Decree-law 236/98. The results relating to total hardness, nitrites, calcium, magnesium, sodium, potassium, aluminium, sulfides and oxidability were compared with the legal values in annex VI as there are no limits relating to these parameters in annexes XXI and I.

Utility of the antibody response to a conjugated Haemophilus influenzae type B vaccine for diagnosis of primary humoral immunodeficiency

Antibody response to an Haemophilus influenzae type b (Hib)-conjugated vaccine was studied in 59 healthy adults (mean age: 32 yr) and 22 patients with humoral immunodeficiencies (mean age: 32 yr) to determine its usefulness in the diagnosis of defective antibody formation. Twenty of the healthy adults and nine of the patients were also immunized with a pneumococcal vaccine. Serum specific antibodies were measured by ELISA. Adequate response to both vaccines was defined using the lower limit of the two-tailed 90% probability interval of postimmunization specific IgG of the healthy adults. By using this cutoff, responders were considered to be those with an absolute increase in anti-Hib IgG titers higher than 2.28 microgram/ml, and in anti-Streptococcus pneumoniae IgG higher than 395 arbitrary units/ml. With these criteria, 85% (50 of 59) of the healthy adults responded with anti-Hib IgG and 75% (15 of 20) with anti-pneumococcal IgG. All healthy adults receiving both vaccines responded to at least one. None of the patients with humoral immunodeficiencies responded to either vaccine. Evaluation of the antibody response to both the Hib and pneumococcal vaccines may facilitate the diagnosis of humoral immunodeficiency and selection of patients to receive immunoglobulin therapy.

Computed tomography vs. magnetic resonance imaging of acute bacterial sinusitis: a rabbit model

PURPOSE

Computed topography (CT) and magnetic resonance imaging (MRI) are important, both clinically and in a research setting, in assessing bacterial sinusitis (BS). The use of CT scanning to evaluate sinus opacification in a reversible model of rabbit acute sinusitis has been reported. MRI offers the potential for better visualization of soft tissue and fluid changes within the paranasal sinuses. MRI has potential as a research tool in animal models of sinusitis. This article compares the use of CT and MRI in measuring maxillary sinus opacification in rabbits during experimental, reversible BS.

MATERIALS AND METHODS

In 2 independent trials, New Zealand White rabbits were imaged for baseline anatomy, and BS was generated by sinus inoculation with Staphylococcus aureus. Serial imaging was performed as a measure of the progression and resolution of BS during the trials. Two experienced, independent reviewers then scored each CT and MRI for percent opacification of the maxillary sinus. These scores were analyzed to assess the degree of agreement between the reviewers.

RESULTS

The correlation coefficients for CT and MRI were 0.6816 and 0.3584, respectively. The Z-statistic comparing these correlation coefficients was significant (P < .0001), indicating that CT is a more precise measure of reversible BS in this rabbit model. Differences in mean scan time and cost per scan were also significantly different (P < .0001), with CT being both quicker and less expensive.

CONCLUSIONS

Greater interobserver consistency of scan interpretation, with less time and cost, make CT the preferred tool for measuring BS in this rabbit model. Attributes of MRI such as better resolution of fluid-tissue interfaces and custom surface coil design for visualization of specific anatomic structures are discussed as they may increase the effectiveness of MRI as an imaging modality in future sinusitis research.

An amplified ELISA inhibition method for the measurement of airborne soybean allergens

BACKGROUND

Measurement of the soybean aeroallergen in Barcelona and other cities where soybean is unloaded is of increasing importance in controlling population exposure and evaluating the influence of such exposure on the persistence of asthma symptoms.

OBJECTIVE

The aims of the study were: (1) to standardize an amplified ELISA inhibition method for the quantification of soybean aeroallergen and (2) to compare this method to a previously described RAST inhibition method.

METHODS AND RESULTS

An amplified competitive ELISA inhibition method with a biotin-streptavidin system was carried out using a pool of sera from soybean-sensitized patients. The results were expressed as U/ml using a low-molecular-mass soybean allergen as reference standard. Reproducibility was calculated by statistically comparing the slope of the regression lines of the standard curve of 4 consecutive assays and by determining the coefficient of variation (CV) of the percent inhibition data for each point of several independent standard curves, each from the same assay (intra-assay) and also from a separate assay (inter-assay). No significant differences in the slopes were obtained by analysis of covariance (ANCOVA) F = 1.04. The CV between assays varied between 4 and 22% (for the assay range used in the reference standard) and was greater than the CV within assays (5-10%). Only values with a CV(%) smaller than 20% were considered acceptable. 78.5% of the samples satisfied this criterion. The RAST inhibition and ELISA inhibition methods were compared by difference plots from the values of 338 air filter eluates. The intraclass correlation coefficient was 0.456 (p < 0.001). After the results of both methods were classified as lower and higher than 165 U/m(3), the kappa index was 0.46 (p < 0.001).

CONCLUSIONS

The data obtained in the present study are comparable to those reported from other similar immunoassays. Moreover, despite the difficulty in comparing air-sampling values from different laboratories, the kappa index may be taken to represent fairly good agreement beyond chance between both methods. All these data demonstrate that the present immunoassay is useful for measuring airborne soybean aeroallergens and can also be applied to evaluate the relationship between exposure and the development of asthma symptoms.

Detection of specific antibodies to pigeon serum and bloom antigens by enzyme linked immunosorbent assay in pigeon breeder's disease

BACKGROUND

Pigeon breeder's disease is an extrinsic allergic alveolitis in the lungs of sensitised people, caused by hypersensitivity reactions to inhaled pigeon antigens. Antigens from different sources of the animal are used for diagnostic purposes, with serum being the most widely used. Bloom is rarely used; very little is known of its antigenicity and diagnostic performance, particularly when used with the enzyme linked immunosorbent assay (ELISA) method, which is the most popular test as it permits measurement of the antibody response.

METHODS

To (a) standardise an ELISA for the measurement of specific IgG against pigeon serum and pigeon bloom extract; (b) to establish reference values for specific IgG in 73 non-exposed controls, (c) to show the presence of specific IgG against pigeon serum and bloom in serum samples of 17 patients with bird fancier's lung and 11 asymptomatic fanciers, and (d) to study the similarity of the two antigen sources by cross reactivity experiments.

RESULTS

Reference values of specific IgG were defined with the 97.5 percentile (367.9 U/ml for pigeon serum and 953.7 U/ml for pigeon bloom extract). Of symptomatic patients 100% had values higher than the cut off for both antigens. In asymptomatic fanciers values were higher than the cut off for pigeon serum in 45% and bloom extract in 54%. Cross reactivity experiments showed that the two antigens differed in antigenic content although some components may be common to both.

CONCLUSION

The ELISA methods used proved to be useful tools for evaluating specific IgG antibody responses against both antigens. The diagnostic performance of both ELISA methods performed with these antigen sources was similar, showing very high sensitivity but moderate specificity. Although some antigenic similarity was found between pigeon serum and bloom extract, cross reactivity studies showed that various antigens seemed to be specific to the bloom extract. However, the antigens responsible for pigeon breeder's disease seem to be present in both antigenic sources.

Sarcocystis levinei infection in Philippine water buffaloes (Bubalus bubalis)

Ultrastructural studies of sarcocysts obtained from Philippine water buffaloes revealed the presence of the commonly reported macroscopic species, Sarcocystis fusiformis, and the microscopic species Sarcocystis levinei (Dissanaike A, Kan S. Studies on Sarcocystis in Malaysia. I: Sarcocystis levinei n.sp. from the water buffalo Bubalus bubalis. Z Parasitenkd 1978;55:127-38), (Huong L, Dubey J, Uggla A. Redescription of Sarcocystis levinei Dissanaike and Kan, 1978 (Protozoa: Sarcocystidae) of the water buffalo (Bubalus bubalis). J Parasitol 1997;83:1148-52). The globular to oval microscopic cysts commonly observed in the muscles of the diaphragm and neck exhibit compartmentalized arrangement of zoites with septal partitions and measure 13-48 microns in diameter. The parasitophorous vacuolar membrane of sarcocyst bears minute and hair-like villar protrusions measuring 2.3-2.75 microns long emanating at certain distances from the primary cyst wall and lack microfilaments. Villar protrusions have expanded to dome-shaped base measuring 0.33-1.6 microns long by 0.22-1.0 micron wide, and intermediate and tapering distal segments bent approximately 90 degrees and run parallel to the cyst surface. The distal segments at some areas join to form conical tufts. The primary cyst wall bears numerous prominent undulations that are arranged in small clusters. The ground substance is 0.42-0.57 micron thick. This paper documents the first report of S. levinei in Philippine water buffaloes possessing the type 7 cyst wall.

Pierre Robin sequences: secondary respiratory difficulties and intrinsic feeding abnormalities

OBJECTIVE

There is considerable variation in opinion regarding the optimal management of patients with Pierre Robin sequence (PRS). No single method of airway intervention or feeding strategy is universally appropriate and effective. This study was performed to examine methods used for airway and feeding management and to identify specific problems encountered.

STUDY DESIGN

A retrospective study of 252 patient charts between 1989 and 1997 at Children's Hospital of Wisconsin.

METHODS

Patient information was collected regarding perinatal history, genetics evaluation, and airway and feeding evaluations and intervention. A group of 47 patients was determined as having PRS.

RESULTS

Secondary respiratory difficulties, defined as respiratory abnormalities in addition to the expected PRS obstruction, were identified in 23% of patients. Also, intrinsic feeding abnormalities not associated with airway obstruction were identified in 11% of patients. Analysis by Fisher's Exact Test revealed patients with a syndromic diagnosis to have a significantly higher rate for tracheotomies and gastrostomy tube placement (P = .041, and P = .0004, respectively). Syndromic patients were also found to have significantly lower Apgar scores and longer hospital stays. Positioning techniques, tongue-lip adhesion, and tracheotomy were also employed effectively with specific indications and specific difficulties that need to be considered.

CONCLUSION

Patients with PRS require thorough airway and feeding evaluation. Those with additional syndromic diagnoses demonstrate higher rates of more invasive interventions. Patients with PRS must undergo individualized approaches with consideration of multiple factors for successful management.

Specific antibody response against the 23-valent pneumococcal vaccine in patients with alpha(1)-antitrypsin deficiency with and without bronchiectasis

OBJECTIVE

To assess the specific antibody response against polyvalent pneumococcal vaccine in patients with alpha(1)-antitrypsin deficiency (AATD) and respiratory infections.

DESIGN AND PARTICIPANTS

We investigated specific IgG, IgG1, and IgG2 antibody responses against the 23-valent antipneumococcal vaccine in 18 patients with AATD phenotype PiZZ, 9 of whom had bronchiectasis and 4 a history of recurrent pneumonia, and compared them with a control group of 40 healthy volunteers.

INTERVENTIONS

Blood samples were drawn just prior to and 3 weeks after immunization.

MEASUREMENTS AND RESULTS

Quantification of specific IgG and its subclasses was performed by an enzyme-linked immunosorbent assay. For patients with AATD, mean increases in specific antipneumococcal titers were 4.7-fold (25 to 75% quartiles, 2.5- to 6.8-fold) for total IgG, 3.2-fold (1.2- to 4.9-fold) for IgG1, and 2.1-fold (1.8- to 3.7-fold) for IgG2. For the control group, the values were 3.3-fold (1.8- to 5.8-fold) for total IgG, 2. 5-fold (1.9- to 3.4-fold) for IgG1, and 3.1-fold (1.9- to 4.5-fold) for IgG2; differences were not significant. Patients with bronchiectasis showed a tendency toward higher levels of IgG subclasses than both control subjects and patients without bronchiectasis; however, there was a tendency toward lower postvaccination serum levels of specific antipneumococcal IgG, IgG1, and IgG2 in patients with bronchiectasis compared with patients without bronchiectasis, but this trend did not reach statistical significance. Three of the four patients with recurrent pneumonia did not show an appropriate IgG2 response.

CONCLUSIONS

These results suggest that, as a group, patients with AATD have a preserved antibody response against pneumococcal polysaccharides. Patients with bronchiectasis show a tendency toward a decreased antibody response, even with increased serum levels of most Ig types. Individuals with an impaired IgG2 response seem to be at increased risk of recurrent pneumonia. Considering the pernicious effect of pulmonary infections on these patients and the preserved antibody response in a majority of them, pneumococcal vaccination should be recommended to patients with AATD.

Blood sample processing effect on eosinophil cationic protein concentration

BACKGROUND

Asthma is considered to be an inflammatory disease. The most important cell involved in the inflammation is the eosinophil. These cells and their mediators, such as eosinophil cationic protein (ECP), are potential markers of the inflammation's severity. Eosinophil cationic protein may be used for monitoring antiasthma treatment. It is well known that sample processing conditions can affect the ECP blood levels.

OBJECTIVE

The aim of this work is to study the effect of temperature, time, and anticoagulants on ECP levels.

METHODS

We studied five asthmatic patients and five healthy controls. We obtained three different blood samples from each subject, one with heparin, one with EDTA, and one without anticoagulant. To evaluate the effect of temperature, serum samples were clotted for an hour, one at 0 degree C, one at room temperature, and the other at 37 degrees C. Plasma (heparin and EDTA) samples were treated as follows: one was immediately centrifuged, and two were stored for an hour, one at 0 degree C, and the other at room temperature. Eosinophil cationic protein levels were measured by fluoroimmunoassay (CAP-System ECP FEIA Pharmacia).

RESULTS

A higher temperature during blood clotting resulted in a higher ECP concentration. There were no differences between ECP determination in serum samples and plasma samples with heparin, under the same conditions of time and temperature; so clotting may not be necessary for ECP release in vitro. Eosinophil cationic protein was not released in plasma samples with EDTA, neither at 0 degree C nor room temperature.

CONCLUSIONS

More studies must be done to clarify the mechanism of the ECP release in vitro.

Characterization of specific immunoglobulin G (IgG) and its subclasses (IgG1 and IgG2) against the 23-valent pneumococcal vaccine in a healthy adult population: proposal for response criteria

The aim of the study was to standardize an enzyme-linked immunosorbent assay (ELISA) method for the quantification of immunoglobulin G (IgG) and its subclasses (IgG1 and IgG2) against the 23-valent pneumococcal vaccine and to establish the criteria for a normal response to the vaccine. Forty healthy individuals (20 women and 20 men; mean age, 29 years) were studied. All were vaccinated with the 23-valent pneumococcal vaccine; blood samples were drawn just prior to and 3 weeks after immunization. Quantification of specific IgG and its subclasses was performed by an ELISA with the vaccine as the antigen. The linearity of the ELISA method was demonstrated by the similar slopes of the linear regression lines generated from the titration of sera with different antibody concentrations. The specificity of the antibodies against the vaccine was demonstrated by (i) an absorption test with pneumococcal vaccine, (ii) a cross-reactivity experiment with Haemophilus influenzae type b polysaccharide, and (iii) affinity chromatography with protein A-Sepharose. Response to the vaccine was defined by using the lower level of the 90% probability interval (one-tailed) for postimmunization-specific IgG, IgG1, and IgG2. By using this cutoff, responders were considered to be those with an absolute increase in antibody titers higher than 395 arbitrary units/ml for IgG, 0.350 A450 units for IgG1, and 0.314 A450 units for IgG2. Overall, 20 (50%) subjects had IgG, IgG1, and IgG2 responses, 9 (22.5%) had IgG and IgG2 responses, 4 (10%) had IgG1 responses, 3 (7.5%) had IgG and IgG1 responses, and 4 (10%) were nonresponders. Ninety percent of our population responded to the 23-valent pneumococcal vaccine. Up to 10% of healthy individuals may respond to an IgG subclass without significant increases in total IgG titers. The ELISA method that is described may be useful for evaluating the specific antibody response against polysaccharides.

IgG subclass deficiencies associated with bronchiectasis

Only a small number of patients with IgG subclass deficiencies (IgGSD) have been observed to have bronchiectasis. Moreover, in the series of patients with bronchiectasis, IgGSD have not been found at any frequency, and the etiology of bronchiectasis remains unclear in 29 to 49% of cases. Serum concentrations of total IgG, IgA, and IgG subclasses as well as pulmonary function were measured in 65 patients (aged: 10 to 74 yr) with bronchiectasis of unknown etiology. An ELISA test was performed to quantify subclasses 1 through 4 using subclass-specific antihuman monoclonal antibodies. IgG subclass estimation in a healthy population with age-stratified normal ranges was derived from 100 adults, 37 children aged between 10 and 12 yr, and 27 adolescents aged between 13 and 16 yr. Serum concentrations of specific IgG antibodies to Haemophilus influenzae type b capsular polysaccharide (Hib-PRP) were also assayed by an ELISA test in 19 of the patients (10 with IgGSD and nine with non-IgGSD) and in 58 healthy individuals before and 3 wk after immunization with Hib-PRP conjugated to meningococcal outer membrane protein complex (OMPC). Thirty-one patients (48%) had low serum concentrations of one or more IgG subclasses (19 IgG2 deficiencies, 2 IgG3 deficiencies, 3 IgG4 deficiencies, and 7 combined subclass deficiencies). All patients showed increased levels of total IgG, IgG1, and IgA, but this rise was significantly higher in patients without IgGSD. Patients with IgGSD showed impaired antibody response to Hib-PRP compared with patients with non-IgGSD and the control group. IgGSD, particularly IgG2 deficiency, are not an unusual cause of bronchiectasis. Therefore, serum levels of IgG subclasses must be assayed whenever other causes of bronchiectasis have been ruled out.