Barriers to organizational adoption of EMR systems in family physician practices: A mixed-methods study in Canada

BackgroundEMR system can provide three main types of benefits: it can solve the logistical organization problems associated with paper systems; it can improve the quality of professionals’ clinical decisions; and it can improve physicians’ return on their practices by reducing the cost of managing clinical information. According to the 2012 Commonwealth Fund International Health Policy Survey, Canada ranked 10th out of 11 countries in terms of family physicians’ adoption of EMR systems. Our main purpose is to investigate the reasons why so many primary care medical practices in this country have not decided to invest in these systems yet.MethodsTo achieve our main objective, a mixed-methods study was performed. We first conducted a Delphi study with a panel of 21 experts made up of general practitioners with extensive professional experience and a very good understanding of the issues surrounding the introduction of health IT in private medical practices. As a second step, we collected and analyzed data from a large questionnaire survey of family physicians working in medical practices without EMR systems (n = 431).ResultsThe Delphi study reveals that private medical practices are hindered by four types of barriers when faced with the initial decision to invest in an EMR system, namely, behavioral, cognitive or knowledge-based, economic, and technological. Survey findings then indicate that the key challenges preventing private medical practices from investing in an EMR system are mainly related to economic and knowledge barriers. Surprisingly, we also found a cluster of medical practices which, although they have not invested in an EMR system, perceive no such barriers to adoption.ConclusionsA thorough understanding of the barriers faced by family physician practices in adopting an EMR system would help governments and other key stakeholders target policies and measures in support of medical practices. The “one size fits all” approach to such policies and measures is clearly inappropriate, given this study's findings that many medical practices face practically no barriers to EMR adoption, and that others differ markedly as to the type of barriers faced, be they mostly “soft” such as knowledge barriers or “hard” such as economic barriers.     

Icon and user interface design for emergency medical information systems: a case study

A usable medical information system should allow for reliable and accurate interaction between users and the system in emergencies. A participatory design approach was used to develop a medical information system in two Turkish hospitals. The process consisted of task and user analysis, an icon design survey, initial icon design, final icon design and evaluation, and installation of the iconic medical information system with the icons. We observed work sites to note working processes and tasks related to the information system and interviewed medical personnel. Emergency personnel then participated in the design process to develop a usable graphical user interface, by drawing icon sketches for 23 selected tasks. Similar sketches were requested for specific tasks such as family medical history, contact information, translation, addiction, required inspections, requests and applications, and nurse observations. The sketches were analyzed and redesigned into computer icons by professional designers and the research team. A second group of physicians and nurses then tested the understandability of the icons. The user interface layout was examined and evaluated by system users, followed by the system's installation. Medical personnel reported the participatory design process was interesting and believed the resulting designs would be more familiar and friendlier.     

Risk factors for wound infection caused by Methicillin Resistant Staphylococcus aureus among hospitalized patients: a case control study from a tertiary care hospital in India

BackgroundMethicillin Resistant Staphylococcus aureus (MRSA) causes infection in hospitals and communities. The prevalence and risk factors of MRSA infection is not homogenous across the globe.ObjectiveTo find the risk factors of MRSA infection among hospitalized patients.MethodsCross-sectional case control study was conducted at a tertiary care hospital in India. The risk factors were collected using checklist from 130 MRSA and 130 Methicillin sensitive staphylococcus aureus (MSSA) infected patients. The pathogens were isolated from the wound swabs according to Clinical and Laboratory Standards Institute guidelines.ResultsBoth the groups were comparable in terms of age, gender, diabetic status, undergoing invasive procedures, urinary catheterization and smoking (p>0.05). Multivariate logistic regression revealed surgical treatment (OR 4.355; CI 1.03, 18.328; p=0.045), prolonged hospitalization (OR 0.307; CI 0.11, 0.832; p=0.020), tracheostomy (OR 5.298, CI 1.16, 24.298; p=0.032), pressure/venous ulcer (OR 7.205; CI 1.75, 29.606; p=0.006) and previous hospitalization (OR 2.883; CI 1.25, 6.631; p=0.013) as significant risk factors for MRSA infection.ConclusionSurgical treatment, prolonged and history of hospitalization, having tracheostomy for ventilation and pressure/venous ulcer were the key risk factors. Therefore, special attention has to be given to the preventable risk factors while caring for hospitalized patients to prevent MRSA infection.     

Transitioning from a computerized provider order entry and paper documentation system to an electronic health record: Expectations and experiences of hospital staff

ObjectivesTo examine healthcare worker's perceptions, expectations, and experiences regarding how work processes, patient-related safety, and care were affected when a quaternary care center transitioned from one computerized provider order entry (CPOE) system to a full electronic health record (EHR).MethodsThe I-SEE survey was administered prior to and 1-year after transition in systems. The construct validity and reliability of the survey was assessed within the current population and also compared to previously published results. Pre- and 1-year post-implementation scale means were compared within and across time periods.ResultsThe majority of respondents were nurses and personnel working in the acute care setting. Because a confirmatory factor analysis indicated a lack of fit of our data to the I-SEE survey's 5-factor structure, we conducted an exploratory factor analysis that resulted in a 7-factor structure which showed better reliability and validity. Mean scores for each factor indicated that attitudes and expectations were mostly positive and score trends over time were positive or neutral. Nurses generally had less positive attitudes about the transition than non-nursing respondents, although the difference diminished after implementation.ConclusionsFindings demonstrate that the majority of responding staff were generally positive about transitioning from CPOE system to a full electronic health record (EHR) and understood the goals of doing so, with overall improved ratings over time. In addition, the I-SEE survey, when modified based on our population, was useful for assessing patient care and safety related expectations and experiences during the transition from one CPOE system to an EHR.     

Rates,levels, and determinants of electronic health record system adoption: A study of hospitals in Riyadh,Saudi Arabia

ObjectiveOutside a small number of OECD countries, little information exists regarding the rates, levels, and determinants of hospital electronic health record (EHR) system adoption. This study examines EHR system adoption in Riyadh, Saudi Arabia.Materials and methodsRespondents from 22 hospitals were surveyed regarding the implementation, maintenance, and improvement phases of EHR system adoption. Thirty-seven items were graded on a three-point scale of preparedness/completion. Measured determinants included hospital size, level of care, ownership, and EHR system development team composition.ResultsEleven of the hospitals had implemented fully functioning EHR systems, eight had systems in progress, and three had not adopted a system. Sixteen different systems were being used across the 19 adopting hospitals. Differential adoption levels were positively related to hospital size and negatively to the level of care (secondary versus tertiary). Hospital ownership (nonprofit versus private) and development team composition showed mixed effects depending on the particular adoption phase being considered.DiscussionAdoption rates compare favourably with those reported from other countries and other districts in Saudi Arabia, but wide variations exist among hospitals in the levels of adoption of individual items. General weaknesses in the implementation phase concern the legacy of paper data systems, including document scanning and data conversion; in the maintenance phase concern updating/maintaining software; and in the improvement phase concern the communication and exchange of health information.ConclusionThis study is the first to investigate the level and determinants of EHR system adoption for public, other nonprofit, and private hospitals in Saudi Arabia. Wide interhospital variations in adoption bear implications for policy-making and funding intervention. Identified areas of weakness require action to increase the degree of adoption and usefulness of EHR systems.     

Utility of hepatitis C virus core antigen testing for diagnosis and treatment monitoring in HCV infection: A study from India

PurposeThe major bottleneck in most developing countries to attain the WHO goal of eliminating hepatitis C as a public health threat by 2030 is the limited access to molecular testing and loss of infected patients to follow up. Many of the hepatitis C virus (HCV) infected patients fail to get the confirmatory HCV RNA test done after initial screening for anti-HCV antibody. The hepatitis C core antigen (HCVcAg) chemiluminescence-based assay which is newly introduced in the Indian health setup could prove to be a potential marker in the single-point screening and confirmation of HCV infection. This study was done to evaluate the performance of the HCVcAg assay for diagnosis and treatment monitoring of patients with HCV infection.MethodsIn this retrospective study 208 archived plasma samples from 184 patients were retrieved and all three markers for the laboratory diagnosis of HCV infection, anti-HCV, HCV RNA and HCVcAg were performed in a single freeze thaw cycle. For a subset of patients (n ​= ​24), paired samples, baseline samples and samples collected at 12 weeks after completion of treatment (SVR12) were available.ResultsThe sensitivity and specificity of the HCVcAg assay were 91.58% and 99.12% respectively with HCV RNA as the gold standard for the detection of active infection. There was a strong correlation between HCVcAg and HCV RNA (R ​= ​0.85, p ​< ​0•0001). Among the paired samples, the concordance between the HCVcAg and HCV RNA at baseline and at SVR12 was 95.8%.ConclusionThe HCVcAg assay showed a good correlation with the gold standard HCV RNA assay, especially in the case of treatment naïve patients. Thus, the use of HCVcAg assay as tool for testing and confirmation of HCV infection has the potential to increase the uptake of HCV testing.     

Plateletpheresis donor deferral patterns at a tertiary care hospital in North India: A need for rethink of haemoglobin cutoff

IntroductionThe donor deferral criteria for blood or apheresis donations are established for two main reasons: (i) to ensure the safety of the blood donor (non-maleficence); (ii) to obtain safe blood of standard quality that has therapeutic benefit for the patient (beneficence). This study was planned to assess the various causes and patterns of plateletpheresis donor deferral in our hospital and to subsequently assess whether any evidence based changes can be done in the current plateletpheresis donor deferral criteria in India to maximize the platelet donor pool without compromising donor safety.Material and methodsThe present study was conducted from May 2021 till June 2022 in the department of transfusion medicine of a tertiary care hospital in North India. The first part of the study was conducted from May 2021 till March 2022 to assess the various causes of donor deferral by analysing the plateletpheresis donor deferral data during the corresponding period. The second part of the study was conducted from April 2022 till June 2022, to assess: (i) average decrease in haemoglobin after plateletpheresis procedure; (ii) red blood cell loss during plateletpheresis procedure; (iii) to determine whether any correlation exists between donor haemoglobin and platelet yield.ResultsDuring the study period, a total of 260 donors were screened for plateletpheresis, out of which 221 (85%) donors were accepted and 39 (15%) donors were deferred for various reasons. Out of the 39 deferred donors, 33 (84.6%) were temporary deferrals, while 6 (15.4%) were permanent deferrals. Low haemoglobin (Hb < 12.5 g/dl) was a cause of deferral in 12.8% (n = 5) of the deferred donors. 192 (73.9%) out of the 260 donors were replacement donors. The calculated mean decrease in haemoglobin as a result of plateletpheresis procedure was 0.4 g/dl. No correlation was seen between donor pre-donation haemoglobin and platelet yield (p = 0.86, r = 0.06, R² = 0.003). The calculated mean red cell loss as a result of plateletpheresis procedure was 28 ml.ConclusionLow haemoglobin (<12.5 g/dl) is a significant cause of temporary plateletpheresis donor deferral in India. In view of the advancement in plateletpheresis technology, which has resulted in minimal red cell loss with the current generation apheresis devices, haemoglobin cutoff of 12.5 g/dl needs to be reconsidered. Perhaps, after performing a multi-centric trial, a consenscus can be reached for revision of haemoglobin cutoff for plateletpheresis donations.     

Prevalence of hepatitis A virus,hepatitis B virus,hepatitis C virus,hepatitis D virus and hepatitis E virus as causes of acute viral hepatitis in North India: A hospital based study

Context: Acute viral hepatitis (AVH) is a major public health problem and is an important cause of morbidity and mortality. Aim: The aim of the present study is to determine the prevalence of hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and hepatitis E virus (HEV) as causes of AVH in a tertiary care hospital of North India. Settings and Design: Blood samples and clinical information was collected from cases of AVH referred to the Grade I viral diagnostic laboratory over a 1-year period. Subjects and Methods: Samples were tested for hepatitis B surface antigen, anti-HCV total antibodies, anti-HAV immunoglobulin M (IgM) and anti-HEV IgM by the enzyme-linked immunosorbent assay. PCR for nucleic acid detection of HBV and HCV was also carried out. Those positive for HBV infection were tested for anti-HDV antibodies. Statistical Analysis Used: Fisher’s exact test was used and a P < 0.05 was considered to be statistically significant. Results: Of the 267 viral hepatitis cases, 62 (23.22%) patients presented as acute hepatic failure. HAV (26.96%) was identified as the most common cause of acute hepatitis followed by HEV (17.97%), HBV (16.10%) and HCV (11.98%). Co-infections with more than one virus were present in 34 cases; HAV-HEV co-infection being the most common. HEV was the most important cause of acute hepatic failure followed by co-infection with HAV and HEV. An indication towards epidemiological shift of HAV infection from children to adults with a rise in HAV prevalence was seen. Conclusions: To the best of our knowledge, this is the first report indicating epidemiological shift of HAV in Uttar Pradesh.     

Diagnostic utility of PCR in detection of clinical cases and carriers of leprosy: A cross sectional study at a tertiary care teaching hospital in central India

PurposeSince ancient era leprosy is existing across the world. India, Indonesia and Brazil still harbour major proportion of global cases. Child leprosy and Grade II disability indicate delayed diagnosis and persistence of transmission in community. So, this study was conducted with aim to evaluate the diagnostic efficacy of PCR in comparison to SSS (Slit Skin Smear) microscopy for detection of leprosy in early stages in both cases and carriers (contacts).MethodsA cross sectional observational study was conducted on 100 subjects including 50 clinically diagnosed new cases of leprosy and their 50 contacts. Each group was subjected to SSS (Slit Skin Smear) microscopy and PCR using RLEP gene as target.ResultsThe overall male: female ratio was 2.44. The Slit Skin smear (SSS) microscopy positivity was 34% (n = 17/50) among cases while it was 0% (n = 0/50) among contacts. The overall positivity for PCR was 42% (n = 42/100) being 66% (n = 33/50) in cases and 18% (n = 9/50) in contacts. About 30% (n = 25/83) of all the microscopically negative subjects were found to be positive by PCR.ConclusionsPCR was found to be a better diagnostic tool both among cases and their contacts. It should be used for screening contacts for early diagnosis and treatment and thus preventing transmission in community.Key messageTo diagnose case and contacts of leprosy in early stages even in very low bacterial density using PCR.     

Implementation and evaluation of an integrated computerized asthma management system in a pediatric emergency department: A randomized clinical trial

ObjectiveThe use of evidence-based guidelines can improve the care for asthma patients. We implemented a computerized asthma management system in a pediatric emergency department (ED) to integrate national guidelines. Our objective was to determine whether patient eligibility identification by a probabilistic disease detection system (Bayesian network) combined with an asthma management system embedded in the workflow decreases time to disposition decision.MethodsWe performed a prospective, randomized controlled trial in an urban, tertiary care pediatric ED. All patients 2–18 years of age presenting to the ED between October 2010 and February 2011 were screened for inclusion by the disease detection system. Patients identified to have an asthma exacerbation were randomized to intervention or control. For intervention patients, asthma management was computer-driven and workflow-integrated including computer-based asthma scoring in triage, and time-driven display of asthma-related reminders for re-scoring on the electronic patient status board combined with guideline-compliant order sets. Control patients received standard asthma management. The primary outcome measure was the time from triage to disposition decision.ResultsThe Bayesian network identified 1339 patients with asthma exacerbations, of which 788 had an asthma diagnosis determined by an ED physician-established reference standard (positive predictive value 69.9%). The median time to disposition decision did not differ among the intervention (228 min; IQR = (141, 326)) and control group (223 min; IQR = (129, 316)); (p = 0.362). The hospital admission rate was unchanged between intervention (25%) and control groups (26%); (p = 0.867). ED length of stay did not differ among intervention (262 min; IQR = (165, 410)) and control group (247 min; IQR = (163, 379)); (p = 0.818).ConclusionsThe control and intervention groups were similar in regards to time to disposition; the computerized management system did not add additional wait time. The time to disposition decision did not change; however the management system integrated several different information systems to support clinicians’ communication.     

Choice of an adequate promoter for efficient complementation in Saccharomyces cerevisiae: a case study

Conservation of the function of open reading frames recently identified in fungal genome projects can be assessed by complementation of deletion mutants of putative Saccharomyces cerevisiae orthologs. A parallel complementation assay expressing the homologous wild type S. cerevisiae gene is generally performed as a positive control. However, we and others have found that failure of complementation can occur in this case. We investigated the specific cases of S. cerevisiae TBF1 and TIM54 essential genes. Heterologous complementation with Candida glabrata TBF1 or TIM54 gene was successful using the constitutive promoters TDH3 and TEF. In contrast, homologous complementation with S. cerevisiae TBF1 or TIM54 genes failed using these promoters, and was successful only using the natural promoters of these genes. The reduced growth rate of S. cerevisiae complemented with C. glabrata TBF1 or TIM54 suggested a diminished functionality of the heterologous proteins compared to the homologous proteins. The requirement of the homologous gene for the natural promoter was alleviated for TBF1 when complementation was assayed in the absence of sporulation and germination, and for TIM54 when two regions of the protein presumably responsible for a unique translocation pathway of the TIM54 protein into the mitochondrial membrane were deleted. Our results demonstrate that the use of different promoters may prove necessary to obtain successful complementation, with use of the natural promoter being the best approach for homologous complementation.     

Correlation between antibiotic consumption and resistance of Pseudomonas aeruginosa in a teaching hospital implementing an antimicrobial stewardship program: A longitudinal observational study

Background/purposeThe rapid emergence of Pseudomonas aeruginosa resistance made selecting antibiotics more challenge. Antimicrobial stewardship programs (ASPs) are urging to implant to control the P. aeruginosa resistance. The purpose of this study is to evaluate the relationship between antimicrobial consumption and P. aeruginosa resistance, the impact of ASPs implemented during the 14-year study period.MethodsA total 14,852 P. aeruginosa isolates were included in our study. The resistant rate and antimicrobial consumption were investigated every six months. Linear regression analysis was conducted to examine the trends in antibiotics consumption and antimicrobial resistance over time. The relationship between P. aeruginosa resistance and antimicrobial consumption were using Pearson correlation coefficient to analysis. The trend of resistance before and after ASPs implanted is evaluated by segment regression analysis.ResultsP. aeruginosa resistance to ceftazidime, gentamicin, amikacin, ciprofloxacin and levofloxacin significantly decreased during the study period; piperacillin/tazobactam (PTZ), cefepime, imipenem/cilastatin and meropenem remained stable. The P. aeruginosa resistance to ciprofloxacin and levofloxacin increasing initial then decreased after strictly controlled the use of levofloxacin since 2007. As the first choice antibiotic to treat P. aeruginosa, the consumption and resistance to PTZ increase yearly and resistance became stable since extended-infusion therapy policy implant in 2009.ConclusionOur ASP intervention strategy, which included extended infusion of PTZ and restrict use of levofloxacin, may be used to control antimicrobial resistance of P. aeruginosa in medical practice.     

Identification of germ cells at risk for neoplastic transformation in gonadoblastoma: an immunohistochemical study for OCT3/4 and TSPY

Carcinoma in situ (CIS) is the precursor of malignant testicular germ cell tumors (GCTs) of adolescents and young adults, being the neoplastic counterpart of primordial germ cells/gonocytes. Carcinoma in situ cells will develop into invasive seminoma/nonseminoma. Gonadoblastoma (GB) is the precursor of invasive GCTs in dysgenetic gonads, predominantly dysgerminoma (DG). In this process, part of the Y chromosome (GBY region) is involved, for which TSPY is a candidate gene. A detailed immunohistochemical survey was performed for the known diagnostic markers, germ cell/placental alkaline phosphatase (PLAP), c-KIT, and OCT3/4, as well as testis-specific protein on the Y chromosome (TSPY) on a series of GBs, and adjacent invasive DGs. All 5 patients were XY individuals (4 females and 1 male). In contrast to c-KIT, PLAP was positive in all cases. The immature germ cells of GBs were positive for OCT3/4, whereas the mature germ cells were negative for this marker, but positive for TSPY. In every GB, a minor population of germ cells positive for both markers could be identified, similar to most CIS cells and early invasive DG. On progression to an invasive tumor, TSPY can be lost, a process that is also detectable in invasive testicular GCTs compared to CIS. These results indicate that GB is a heterogeneous mix of germ cells, in which the OCT3/4-positive cells have the potential to undergo progression to an invasive tumor. These early invasive stages are initially also positive for TSPY (like CIS), supporting a positive selection mechanism. Therefore, OCT3/4 in combination with TSPY is valuable to identify malignant germ cells in dysgenetic gonads. This could allow better prediction of the risk of progression to a GCT. In addition, the data support the model that GB represents the earliest accessible developmental stage of malignant GCTs.     

Evaluating genotoxicity data to identify a mode of action and its application in estimating cancer risk at low doses: A case study involving carbon tetrachloride

In the new USEPA cancer risk assessment guidelines, mode of action (MoA) information, combined with a determination of whether or not a chemical is mutagenic, plays an important role in determining whether a linear or nonlinear approach should be used to estimate cancer risks at low doses. In this article, carbon tetrachloride (CT) is used as an example to illustrate how mixed genotoxicity data can be evaluated and used to identify a likely MoA. CT is essentially negative in inducing gene mutations in Salmonella, but is consistently positive in inducing recombination and aneuploidy in fungi. Negative or equivocal results were seen in most in vitro and in vivo studies in mammals, including mutation studies in transgenic mice. However, DNA adducts, primarily those derived from oxidation- and lipid-peroxidation-derived products as well as DNA double-strand breaks and micronucleated cells, have been seen repeatedly in the liver of CT-treated animals. On the basis of the weight of evidence, CT should not be considered a directly mutagenic agent. Mutagenic as well as other genotoxic effects, as they occur, will most likely be generated through indirect mechanisms resulting from oxidative and lipid peroxidative damage and/or damage occurring during necrosis or apoptosis. As key events in this process are expected to occur in a nonlinear fashion, the expected relationship between CT dose and carcinogenic response in the liver is likely to be nonlinear with a steep dose response. This conclusion is consistent with rodent cancer bioassay results in which steep nonlinear dose responses have been seen.     

Utility of immunohistochemistry with an antibody against MYC at the initial diagnosis of follicular lymphoma,grade 3A,for predicting a more aggressive clinical course: a case report and review of the literature

Follicular lymphoma (FL) is the most common indolent lymphoma, and associated with the chromosomal translocation t(14;18)(q32;q21). While, FL harboring both BCL2 and MYC translocation at diagnosis is very rare. The evaluation of MYC expression in typical FL at presentation using southern blot, G-banded karyotyping or fluorescence in situ hybridization (FISH) analyses has been described so far. However, there are no reports about the use of immunohistochemistry (IHC) to evaluate MYC protein expression in FL at presentation. Here, we present a FL patient who transformed to a B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt’s lymphoma, accompanied by concurrent BCL2, BCL6, and MYC translocations; i.e., triple-hit lymphoma. Paraffin-embedded tissue section-FISH analysis demonstrated that the FL was negative for MYC, but MYC protein expression was subsequently detected in the lymph node specimen obtained at the initial diagnosis using IHC. This case revealed aggressive clinical course and central nervous system involvement. In the literature concerning MYC positive FL five out of 8 patients were dead within 24 months. The detection of MYC protein expression in FL using IHC might be useful to predict more aggressive clinical course.     

Development of an in vitro system for the study of allergens and allergen-specific immunoglobulin E and immunoglobulin G: Fcɛ receptor I supercross-linking is a possible new mechanism of immunoglobulin G-dependent enhancement of type I allergic reactions

BACKGROUND: IgE-dependent activation of mast cells (MCs) is a key pathomechanism of type I allergies. In contrast, allergen-specific IgG Abs are thought to attenuate immediate allergic reactions by blocking IgE binding and by cross-linking the inhibitory Fcgamma receptor IIB on MCs. OBJECTIVES: To establish a defined in vitro system using human MCs to study the biological activity of allergens and to investigate the role of allergen-specific IgE and IgG. METHODS: Purified human intestinal MCs sensitized with different forms of specific IgE Abs were triggered by monomeric and oligomeric forms of recombinant Bet v 1, the major birch pollen allergen, in the presence or absence of allergen-specific IgG Abs. Results MCs sensitized with an anti-Bet v 1 IgE mAb or sera obtained from birch pollen allergic patients released histamine and sulphidoleukotrienes after exposure to oligomeric Bet v 1. Monomeric Bet v 1 provoked mediator release only in MCs sensitized with patients sera but not in MCs sensitized with anti-Bet v 1 IgE mAb. Interestingly, MC activation could be induced by supercross-linking of monomeric Bet v 1 bound to monovalent IgE on MCs with a secondary allergen-specific IgG pAb. By using IgG F(ab')2 fragments we provide evidence that this effect is not a result of IgG binding to Fcgamma receptors. CONCLUSION: This assay represents a new tool for the in vitro study of MC activation in response to natural and genetically modified allergens. Fcepsilon receptor I supercross-linking by allergen-specific IgG Abs provides a possible new mechanism of IgG-dependent enhancement of type I allergic reactions.