Retrospective Analysis of Adverse Drug Events Between Nafcillin Versus Cefazolin for Treatment of Methicillin-Susceptible Staphylococcus aureus Infections.

Background: Nafcillin or cefazolin are drugs of choice for methicillin-susceptible Staphylococcus aureus (MSSA) infections. Prior studies indicate a higher incidence of acute kidney injury (AKI) with nafcillin, although AKI classification and time to occurrence is not well described. Objective: To characterize the incidence and time to adverse drug events for nafcillin versus cefazolin in the inpatient setting. Methods: A retrospective cohort study evaluated hospitalized, adult patients receiving intravenous nafcillin or cefazolin for treatment of MSSA infection. Incidence and time to AKI based on RIFLE criteria were measured. Secondary end points included antibiotic discontinuation and incidence of neutropenia, thrombocytopenia, elevated transaminases, and Clostridioides difficile infection (CDI). Results: Of 324 patients who received nafcillin (n = 119) or cefazolin (n = 205), higher rates of AKI were found for nafcillin versus cefazolin (19% vs 2%, respectively; P < 0.0001). Median time to AKI with nafcillin was 6.5 days (range, 3-14 days). The majority of patients were classified as RIFLE "Risk" stratum. Nafcillin treatment discontinuations were more frequent than for cefazolin (17.6% vs 0.9%, respectively; P < 0.0001). Nafcillin was an independent predictor of AKI (odds ratio = 12.4; 95% CI = 4.14-47.60, P < 0.0001). No differences in neutropenia, thrombocytopenia, elevated transaminases, or CDI were observed. Conclusion and Relevance: Nafcillin displayed higher rates of AKI at a median of 1 week of therapy, which provides a framework for clinician monitoring and consideration of antibiotic modification. Most patients developed "Risk" class AKI (RIFLE classification), which may be reversible with prompt intervention.

Strategies for Successful Management of Severe Atopic Dermatitis.

Patients with severe atopic dermatitis (AD) are reported to represent between 10% and 18% of all patients with AD. However, in this subgroup of patients, quality of life is significantly affected and patients may have a number of atopic and nonatopic comorbidities. Treatment of this severe population has often been reactive with inappropriate use of systemic corticosteroids and unapproved immunosuppressants. Recent insights point to the systemic nature of AD, which has important therapeutic implications. Management of severe AD requires a comprehensive approach that incorporates proper diagnosis, assessment of disease severity, and impact on patient's and caregiver's quality of life, along with education regarding the chronic relapsing nature of the disease as well as treatment options. Biologics such as dupilumab offer a novel, targeted therapeutic approach for this systemic disease.

Impact of Procalcitonin Guidance on Management of Adults Hospitalized with Chronic Obstructive Pulmonary Disease Exacerbations.

BACKGROUND: Antibiotics are often prescribed for hospitalized patients with chronic obstructive pulmonary disease (COPD) exacerbations. The use of procalcitonin (PCT) in the management of pneumonia has safely reduced antibiotic durations, but limited data on the impact of PCT guidance on the management of COPD exacerbations remain. OBJECTIVE: To determine the impact of PCT guidance on antibiotic utilization for hospitalized adults with exacerbations of COPD. DESIGN: A retrospective, pre-/post-intervention cohort study was conducted to compare the management of patients admitted with COPD exacerbations before and after implementation of PCT guidance. The pre-intervention period was March 1, 2014, through October 31, 2014, and the post-intervention period was March 1, 2015, through October 31, 2015. PARTICIPANTS: All patients with hospital admissions during the pre- and post-intervention period with COPD exacerbations were included. Patients with concomitant pneumonia were excluded. INTERVENTION: Availability of PCT laboratory values in tandem with a PCT guidance algorithm and education. MAIN MEASURES: The primary outcome was duration of antibiotic therapy for COPD. Secondary objectives included duration of inpatient length of stay (LOS) and 30-day readmission rates. KEY RESULTS: There were a total of 166 and 139 patients in the pre- and post-intervention cohorts, respectively. There were no differences in mean age (66.2 vs. 65.9; P = 0.82) or use of home oxygenation (34% vs. 39%; P = 0.42) in the pre- and post-intervention groups, respectively. PCT guidance was associated with a reduced number of antibiotic days (5.3 vs. 3.0; p = 0.01) and inpatient LOS (4.1 days vs. 2.9 days; P = 0.01). Respiratory-related 30-day readmission rates were unaffected (10.8% vs. 9.4%; P = 0.25). CONCLUSIONS: Utilizing PCT guidance in the management of COPD exacerbations was associated with a decreased total duration of antibiotic therapy and hospital LOS without negatively impacting hospital readmissions.

Impact of Procalcitonin Guidance with an Educational Program on Management of Adults Hospitalized with Pneumonia.

BACKGROUND: Community-acquired pneumonia and healthcare-associated pneumonia are often treated with prolonged antibiotic therapy. Procalcitonin (PCT) has effectively and safely reduced antibiotic use for pneumonia in controlled studies. However, limited data exist regarding PCT guidance in real-world settings for management of pneumonia. METHODS: A retrospective, preintervention/postintervention study was conducted to compare management for patients admitted with pneumonia before and after implementation of PCT guidance at 2 teaching hospitals in Pittsburgh, Pennsylvania. The preintervention period was March 1, 2014 through October 31, 2014, and the postintervention period was March, 1 2015 through October 31, 2015. RESULTS: A total of 152 and 232 patients were included in the preintervention and postintervention cohorts, respectively. When compared with the preintervention group, mean duration of therapy decreased (9.9 vs 6.0 days; P < .001). More patients received an appropriate duration of 7 days or less (26.9% vs 66.4%; P < .001). Additionally, mean hospital length of stay decreased in the postintervention group (4.9 vs 3.5 days; P = .006). Pneumonia-related 30-day readmission rates (7.2% vs 4.3%; P = .26) were unaffected. In the postintervention group, patients with PCT levels <0.25 µg/L received shorter mean duration of therapy compared with patients with levels >0.25 µg/L (4.6 vs 8.0 days; P < .001), as well as reduced hospital length of stay (3.2 vs 3.9 days; P = .02). CONCLUSIONS: In this real-world study, PCT guidance led to shorter durations of total antibiotic therapy and abridged inpatient length of stay without affecting hospital readmissions.

Effect of Antimicrobial Stewardship Program Guidance on the Management of Uncomplicated Skin and Soft Tissue Infections in Hospitalized Adults.

OBJECTIVE: To assess the effect of an antimicrobial stewardship program (ASP)-bundled initiative on the appropriate use of antibiotics for uncomplicated skin and soft tissue infections (uSSTIs) at 2 academic medical centers in Pittsburgh, Pennsylvania. PATIENTS AND METHODS: A retrospective preintervention and postintervention study was conducted to compare management of patients admitted with uSSTIs before and after the implementation of the bundled initiative. The preintervention period was from August 1, 2014, through March 31, 2015, and the postintervention period was from August 1, 2015, through March 31, 2016. RESULTS: A total of 160 patients were included in the preintervention cohort, and 163 were included in the postintervention cohort. Compared with the preintervention group, the mean duration of therapy decreased (12.5 days vs 8.8 days; P<.001) and an appropriate duration of less than 10 days increased in more patients (20.6% [33 of 160] vs 68.7% [112 of 163]; P<.001) in the postintervention period. Fewer patients were exposed to antimicrobials with extended gram-negative (44.4% [71 of 160] vs 9.2% [15 of 163]; P<.001), anaerobic (39.4% [63 of 160] vs 9.8% [16 of 163]; P<.001), and antipseudomonal (16.3% [26 of 160] vs 1.8% [3 of 163]; P<.001) coverage. The mean length of stay decreased from 3.6 to 2.2 days (P<.001) without an increase in 30-day readmissions (6.3% [10 of 160] vs 4.9% [8 of 163]; P=.64). The ASP made recommendations for 125 patients, and 96% were accepted. CONCLUSION: Implementation of an ASP-bundled approach aimed at optimizing antibiotic therapy in the management of uSSTIs led to shorter durations of narrow-spectrum therapy as well as shorter hospital length of stay without adversely affecting hospital readmissions.

HLA compatibility assessment and management of highly sensitized patients under the new kidney allocation system (KAS): A 2016 status report from twelve HLA laboratories across the U.S.

Twelve HLA laboratories were surveyed to assess the methods and operational issues involved to define highly sensitized patients and to assess HLA compatibility under the new kidney allocation system (KAS) in the U.S. All laboratories used single antigen bead assays both pre- and post-KAS to define both broad and allele-specific HLA antibodies. The methods and threshold used to list HLA unacceptable antigens in UNet for virtual crossmatch (vXM) and the criteria used for determining HLA compatibility varied among laboratories. Laboratories reported several limitations of the current assays including the accuracy of quantifiable antibody fluorescence values, inadequate coverage of common alleles on the bead panels, and challenges in calibrating the vXM. The new KAS has resulted in a significant surge of deceased donor organ offers requiring vXM evaluation under tight time constraints. In the post-KAS period, eight of twelve laboratories (67%) indicated that their center did not proceed to transplant based on vXM without a prospective lymphocyte crossmatch. In conclusion, HLA laboratories play a critical role in deceased donor allocation for highly sensitized patients under the new KAS. Significant opportunities exist to improve the methods used in the assessment of HLA compatibility to safely transplant highly sensitized patients.

Appropriateness of antibiotic management of uncomplicated skin and soft tissue infections in hospitalized adult patients.

BACKGROUND: Skin and soft tissue infections (SSTIs) are a leading cause for hospitalizations in the United States. Few studies have addressed the appropriateness of antibiotic therapy in the management of SSTIs without complicating factors. We aimed to determine the appropriateness of antibiotic treatment duration for hospitalized adult patients with uncomplicated SSTIs. METHODS: This was a retrospective analysis performed at two academic medical centers in Pittsburgh, Pennsylvania on patients aged 18 years and older with primary ICD-9 code for SSTIs admitted August 1st, 2014-March 31st, 2015. The primary outcome was the appropriateness of antibiotic treatment duration for uncomplicated SSTIs. Secondary objectives included the appropriateness of antibiotic agent spectrum, duration of inpatient length of stay (LOS), utilization of blood cultures and advanced imaging modalities, and re-hospitalization for SSTI within 30 days of discharge from the index admission. RESULTS: A total of 163 episodes were included in the cohort. The mean duration of total antibiotic therapy was 12.6 days. Appropriate duration was defined as receipt of total antibiotic duration of less than 10 days and occurred in 20.2% of patients. Twenty eight percent of patients received antibiotics for greater than 14 days. Seventy three (44.8%) patients received greater than 24 h of inappropriate extended spectrum gram-negative coverage; 65 (39.9%) received anaerobic coverage. CONCLUSIONS: In the majority of patients, treatment duration was excessive. Inappropriate broad spectrum antibiotic selection was utilized with regularity for SSTIs without complicating factors. The management of uncomplicated SSTIs represents a significant opportunity for antimicrobial stewardship.

HLA-A, -B, -C, -DR, and -DQ Matching in Pancreas Transplantation: Effect on Graft Rejection and Survival.

To enhance selection of appropriate deceased donors for pancreas transplants, we sought to determine whether HLA matching improved posttransplantation outcomes. In this single-center study of 1219 pancreas transplants, we correlated posttransplantation outcomes with HLA-A, -B, -C, -DR, and -DQ matches and mismatches. Rejection was linearly correlated with the number of mismatches. The individual number of HLA mismatches reached significance at four or more with a 2.3- to 2.9-fold increase in rejection. The effect was most predominant with HLA-B (1.8-fold with one mismatch and 2.0-fold with two mismatches) and -DR (1.9-fold with two mismatches) loci, whereas HLA-A, -C, and -DQ matches or mismatches did not independently predict acute rejection. The affect was strongest in solitary pancreas transplants, with little impact for simultaneous pancreas and kidney (SPK). In contrast, HLA matching did not affect graft or patient survival rates but was associated with a reduced risk of opportunistic infection. Avoidance of acute rejection saved an estimated $32 000 for solitary pancreas recipients and $52 000 for SPK recipients in hospital costs. Our data do not support the use of HLA matching for predicting pancreas graft survival but do support its significance for the reduction of acute rejection, particularly for solitary pancreas recipients.

High frequency of nonadherence to Clostridium difficile treatment guidelines.

OBJECTIVES: The 2010 Infectious Diseases Society of America/Society for Healthcare Epidemiology of America treatment guidelines for Clostridium difficile infections (CDI) recommend oral metronidazole for mild-to-moderate disease and oral vancomycin for severe disease. Given that disease severity is easily determined by the peripheral white blood cell count and serum creatinine level, a computerized decision support (CDS) pathway to guide treatment is inherently appealing. Because providers often override or ignore the computer-based alerts, the proposed CDS pathway should be justified before implementation. METHODS: We undertook this study to ascertain the frequency of nonadherence to CDI guidelines. Between October 1, 2007 and September 30, 2008, a total of 229 cases were screened and 78 cases were included in the study, which took place at a 661-bed acute tertiary care teaching hospital. RESULTS: During the year-long study of CDI cases at our tertiary care hospital, 61.5% (48/78) of the patients received an antibiotic regimen that was not recommended by the 2010 guidelines. Among the 35 patients with mild-to-moderate CDI, 85.7% (30/35) received the recommended treatment of oral metronidazole monotherapy; in contrast, among the 43 patients with severe disease, none (0/43) received the recommended treatment of oral vancomycin monotherapy (P < 0.01). Moreover, 17.9% (14/78) of patients received concurrent oral metronidazole and vancomycin, a regimen that is not recommended anywhere in the Infectious Diseases Society of America/Society for Healthcare Epidemiology of America guidelines and which may be associated with a poor outcome. Patients who received combination oral metronidazole and vancomycin were not more likely to have comorbidities or severe CDI compared with those who received a single antibiotic agent. CONCLUSIONS: As a result of this study, we plan to educate our providers on the treatment of CDI through a CDS pathway in an effort to increase guideline adherence, decrease inappropriate antibiotic use, and potentially improve patient outcomes.

Common and well-documented HLA alleles: 2012 update to the CWD catalogue.

We have updated the catalogue of common and well-documented (CWD) human leukocyte antigen (HLA) alleles to reflect current understanding of the prevalence of specific allele sequences. The original CWD catalogue designated 721 alleles at the HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQA1, -DQB1, and -DPB1 loci in IMGT (IMmunoGeneTics)/HLA Database release 2.15.0 as being CWD. The updated CWD catalogue designates 1122 alleles at the HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQA1, -DQB1, -DPA1 and -DPB1 loci as being CWD, and represents 14.3% of the HLA alleles in IMGT/HLA Database release 3.9.0. In particular, we identified 415 of these alleles as being 'common' (having known frequencies) and 707 as being 'well-documented' on the basis of ~140,000 sequence-based typing observations and available HLA haplotype data. Using these allele prevalence data, we have also assigned CWD status to specific G and P designations. We identified 147/151 G groups and 290/415 P groups as being CWD. The CWD catalogue will be updated on a regular basis moving forward, and will incorporate changes to the IMGT/HLA Database as well as empirical data from the histocompatibility and immunogenetics community. This version 2.0.0 of the CWD catalogue is available online at cwd.immunogenomics.org, and will be integrated into the Allele Frequencies Net Database, the IMGT/HLA Database and National Marrow Donor Program's bioinformatics web pages.

Delays in the administration of antimicrobials in the emergency department and the impact of an educational intervention to improve this administration.

OBJECTIVES: The aim of the study was to assess the factors associated with delays in emergency department (ED) antimicrobial administration and to determine whether an educational intervention would reduce the incidence of such delays. METHODS: We carried out a retrospective observational cohort study of patients aged 18-89 years who received intravenous antimicrobial(s) in a single ED and were subsequently admitted (March 2011). Using multivariable logistic regression, we analyzed whether demographic and operational factors were significantly associated with delayed ED antimicrobial administration (> 30 min from physician order to nurse initiation time). We then conducted an educational intervention with ED/hospital staff to disseminate knowledge of these identified factors. After the intervention, we carried out a prospective observational cohort study of participants with the same inclusion criteria (March 2012), using the large sample z-test to analyze whether the incidence of such delays was significantly reduced. RESULTS: A total of 575 ED antimicrobial orders (302 patients) before the intervention and 493 antimicrobial orders (275 patients) after the intervention fulfilled the inclusion criteria. The median time to antimicrobial administration (interquartile) was 48 min (17-130 min) before the intervention and 49 min (17-156 min) after the intervention. Variables significantly increasing or decreasing the odds of delayed ED antimicrobial administration were older age [OR: 1.01, 95% confidence interval (CI) 1.003-1.03], one-time dosing (OR: 0.53, 95% CI 0.31-0.92), and second (OR: 2.40, 95% CI 1.39-4.14), and third (OR: 3.66, 95% CI 1.69-7.92) antimicrobial administration (multiple agents ordered). The incidence of antimicrobial administration was 35.8% within 30 min before the intervention and 34.7% after the intervention (z-test: 0.39, P = 0.70). CONCLUSION: Older age, multiple agent orders, and dosing ordering pattern showed a significant association with delays in ED antimicrobial administration. An educational intervention to disseminate knowledge of these factors did not result in a reduction in such delays.

Perceptions of participating emergency nurses regarding an ED seasonal influenza vaccination program.

INTRODUCTION: Numerous professional organizations have recommended that emergency departments provide influenza vaccine to patients. However, no study has reported on the perceptions of participating emergency nurses regarding ED influenza vaccination programs. METHODS: We conducted an anonymous Web-based survey to assess the post-participation perceptions of emergency nurses regarding an ED influenza vaccination protocol. The vaccination protocol occurred at an urban, academic emergency department and was designed to be performed by emergency nurses without added staffing resources by using ED Electronic Medical Record technology. Data from the Web-based survey were analyzed using descriptive statistics and χ(2) analysis to assess significant associations of where emergency nurses believed the protocol was time inefficient. RESULTS: The ED influenza vaccination protocol was in effect from October 1-25, 2009, with 3091 eligible ED visits and 613 patients receiving ED seasonal influenza vaccination. Fifty-eight of 59 participating emergency nurses (98%) responded to the survey. Significant findings were that 59% of responding emergency nurses found the protocol too time consuming and believed it was inappropriate in the ED setting. Responding emergency nurses reported that protocol efficiency could be improved by adding staff, simplifying screening and vaccination documentation requirements, and improving vaccine supply and stocking procedures in the emergency department. CONCLUSION: A majority of surveyed emergency nurses who had participated in an ED influenza vaccination program reported that the protocol was too time consuming and inappropriate for the ED setting. Surveyed emergency nurses expressed the opinion that such protocols required added staff, simplified patient consent/vaccination documentation requirements, and improved vaccine supply and stocking processes.

Revisiting traditional risk factors for rejection and graft loss after kidney transplantation.

Single-antigen bead (SAB) testing permits reassessment of immunologic risk for kidney transplantation. Traditionally, high panel reactive antibody (PRA), retransplant and deceased donor (DD) grafts have been associated with increased risk. We hypothesized that this risk was likely mediated by (unrecognized) donor-specific antibody (DSA). We grouped 587 kidney transplants using clinical history and single-antigen bead (SAB) testing of day of transplant serum as (1) unsensitized; PRA = 0 (n = 178), (2) third-party sensitized; no DSA (n = 363) or (3) donor sensitized; with DSA (n = 46), and studied rejection rates, death-censored graft survival (DCGS) and risk factors for rejection. Antibody-mediated rejection (AMR) rates were increased with DSA (p < 0.0001), but not with panel reactive antibody (PRA) in the absence of DSA. Cell-mediated rejection (CMR) rates were increased with DSA (p < 0.005); with a trend to increased rates when PRA>0 in the absence of DSA (p = 0.08). Multivariate analyses showed risk factors for AMR were DSA, worse HLA matching, and female gender; for CMR: DSA, PRA>0 and worse HLA matching. AMR and CMR were associated with decreased DCGS. The presence of DSA is an important predictor of rejection risk, in contrast to traditional risk factors. Further development of immunosuppressive protocols will be facilitated by stratification of rejection risk by donor sensitization.

The contribution of the nursing service worldwide and its capacity to benefit within the dermatology field.

The nursing service is a significant element in the dermatological capacity to respond to skin care and dermatological needs worldwide. Although it is an area of development often neglected by dermatologists, it is one that is undergoing rapid and substantial evolution. This paper outlines the initiatives undertaken by nurses to enhance their contribution, and examines the development of nursing within the dermatology field. It argues for the need to develop a service delivery model in dermatology care that utilizes specialist-nursing expertise to cascade dermatological knowledge and skill through primary care. The paper summarizes the strategic importance of nursing in dermatology care delivery, whether in resource-rich or -poor countries, and its unmet potential in the capacity to benefit and meet skin care and dermatological care needs. The paper specifically focuses on the development work led by the International Skin Care Nursing Group (ISNG) to stimulate and develop the capacity of nursing to respond to these widespread needs through promoting service delivery models that operate interdependently with dermatologist-led care.

Multidrug-resistant gram-negative infections. Bringing back the old.

Multidrug-resistant (MDR) gram-negative infections have become challenging to treat when there is only a limited armamentarium of anti-infectives that are commercially available. In particular, increasing resistance of gram-negative organisms such as Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter species have become concerning. Carbapenems have been used to treat extended-spectrum-ß-lactamase (ESBL)-producing Escherichia coli and Klebsiella species infections. However, because of carbapenemase-producing K pneumoniae strains, other MDR gram-negative infection treatment options are limited to antibiotics with in vitro spectrum of activity against these MDR pathogens and may include the use of tigecycline, polymyxin B, or polymxyin E (colistin). Because of the potential for nephrotoxicity or neurotoxicity with the polymyxins, clinicians should be vigilant in preventing its adverse effects. Clinicians are encouraged to support the Infectious Diseases Society of America's 10 × '20 Initiative in gaining global commitment to develop additional antimicrobials for the future.

Feasibility of integrating a clinical decision support tool into an existing computerized physician order entry system to increase seasonal influenza vaccination in the emergency department.

While emergency department (ED) seasonal influenza vaccination programs are feasible, reported implementation barriers include added staffing requirements to identify eligible patients and getting busy ED personnel to order and provide vaccination. We present a prospective, observational trial of integrating a clinical decision support tool into an existing ED computerized physician order entry (CPOE) system to increase ED seasonal influenza vaccination without added staffing resources, the operational barriers identified to program implementation, the revenue generated and data on opportunities for future quality improvement. Compared to the comparable pre-protocol period, ED influenza vaccination rose by 17.5% with a resultant profit margin of 34.5%.

Fever of unknown origin: a case of cardiac myxoma infected with Staphylococcus lugdunensis.

Infected cardiac myxoma is a rare entity. It poses a diagnostic challenge as clinical presentation may reflect an underlying infectious, immune, or a neoplastic disease process. To the best of our knowledge, the first case of a cardiac myxoma infected with Staphylococcus lugdunensis is reported in a 54-year-old man with fever of unknown origin for 4 months. Successful excision of the tumor was performed and was followed by an uneventful recovery. Clinical presentation, diagnosis, and management of infected cardiac myxomas are discussed.

The HLA dictionary 2008: a summary of HLA-A, -B, -C, -DRB1/3/4/5, and -DQB1 alleles and their association with serologically defined HLA-A, -B, -C, -DR, and -DQ antigens.

The 2008 report of the human leukocyte antigen (HLA) data dictionary presents serologic equivalents of HLA-A, -B, -C, -DRB1, -DRB3, -DRB4, -DRB5, and -DQB1 alleles. The dictionary is an update of the one published in 2004. The data summarize equivalents obtained by the World Health Organization Nomenclature Committee for Factors of the HLA System, the International Cell Exchange, UCLA, the National Marrow Donor Program, recent publications, and individual laboratories. The 2008 edition includes information on 832 new alleles (685 class I and 147 class II) and updated information on 766 previously listed alleles (577 class I and 189 class II). The tables list the alleles with remarks on the serologic patterns and the equivalents. The serological equivalents are listed as expert assigned types, and the data are useful for identifying potential stem cell donors who were typed by either serology or DNA-based methods. The tables with HLA equivalents are available as a searchable form on the IMGT/HLA database Web site (http://www.ebi.ac.uk/imgt/hla/dictionary.html).

Strategies and technical challenges in allele level Class II typing in 2578 bone marrow transplantation donor-recipient pairs.

Human leukocyte antigen typing of 2578 donor-recipient pairs whose transplantation was facilitated by the National Marrow Donor Program allowed for an in-depth analysis of the accuracy of high-volume allele level testing data. The methods employed provided allele level typing at DRB1/3/5, DQA1, DQB1, DPA1, and DPB1 using sequence-specific oligonucleotide probe hybridization (SSOPH), polymerase chain reaction (PCR) restriction fragment length polymorphism analysis, sequence specific PCR, and direct sequence-based typing (SBT). Each typing was independently tested by two laboratories in Phase 1, and in subsequent phases targeted samples were typed in duplicate by SBT to monitor typing quality. Comparison with prior transplant center typing was also evaluated. SSOPH detected discrepancies ranged from 0.6% at DPB1 to 5.1% at DQB1 in Phase 1. The majority of discrepancies, 62%, resulted from human error such as sample handling, result interpretation, or clerical errors. Alleles that are frequently discrepant have been identified in this predominantly white population.