Tande, Aaron J.

Aims The aim of this study was to determine the diagnostic accuracy of α defensin (AD) lateral flow assay (LFA) and enzyme-linked immunosorbent assay (ELISA) tests for periprosthetic joint infection (PJI) in comparison to conventional synovial white blood cell (WBC) count and polymorphonuclear neutrophil percentage (PMN%) analysis. Methods Patients undergoing joint aspiration for evaluation of pain after total knee arthroplasty (TKA) or total hip arthroplasty (THA) were considered for inclusion. Synovial fluids from 99 patients (25 THA and 74 TKA) were analyzed by WBC count and PMN% analysis, AD LFA, and AD ELISA. WBC and PMN% cutoffs of ≥ 1,700 cells/mm3 and ≥ 65% for TKA and ≥ 3,000 cells/mm3 and ≥ 80% for THA were used, respectively. A panel of three physicians, all with expertise in orthopaedic infections and who were blinded to the results of AD tests, independently reviewed patient data to diagnose subjects as with or without PJI. Consensus PJI classification was used as the reference standard to evaluate test performances. Results were compared using McNemar’s test and area under the receiver operating characteristic curve (AUC) analysis. Results Expert consensus classified 18 arthroplasies as having failed due to PJI and 81 due to aseptic failure. Using these classifications, the calculated sensitivity and specificity of AD LFA was 83.3% (95% confidence interval (CI) 58.6 to 96.4) and 93.8% (95% CI 86.2 to 98.0), respectively. Sensitivity and specificity of AD ELISA was 83.3% (95% CI 58.6 to 96.4) and 96.3% (95% CI 89.6 to 99.2), respectively. There was no statistically significant difference between sensitivity (p = 1.000) or specificity (p = 0.157) of the two AD assays. AUC for AD LFA was 0.891. In comparison, AUC for synovial WBC count, PMN%, and the combination of the two values was 0.821 (sensitivity p = 1.000, specificity p < 0.001), 0.886 (sensitivity p = 0.317, specificity p = 0.011), and 0.926 (sensitivity p = 0.317, specificity p = 0.317), respectively. Conclusion The diagnostic accuracy of synovial AD for PJI diagnosis is comparable and not statistically superior to that of synovial WBC count plus PMN% combined. Cite this article: Bone Joint J 2021;103-B(6):1119–1126.

Abstract In a large cohort of United States healthcare personnel without prior coronavirus disease 2019 (COVID-19) infection, 94 382 doses of messenger RNA (mRNA) COVID-19 vaccine were administered to 49 220 individuals. The adjusted vaccine effectiveness following 2 doses of each of the 2 available brands of mRNA vaccine exceeded 96%.

Abstract Background Several vaccines are now available under emergency use authorization in the United States and have demonstrated efficacy against symptomatic COVID-19. Vaccine impact on asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is largely unknown. Methods We conducted a retrospective cohort study of consecutive, asymptomatic adult patients (n = 39 156) within a large US healthcare system who underwent 48 333 preprocedural SARS-CoV-2 molecular screening tests between 17 December 2020 and 8 February 2021. The primary exposure of interest was vaccination with ≥1 dose of an mRNA COVID-19 vaccine. The primary outcome was relative risk (RR) of a positive SARS-CoV-2 molecular test among those asymptomatic persons who had received ≥1 dose of vaccine compared with persons who had not received vaccine during the same time period. RR was adjusted for age, sex, race/ethnicity, patient residence relative to the hospital (local vs nonlocal), healthcare system regions, and repeated screenings among patients using mixed-effects log-binomial regression. Results Positive molecular tests in asymptomatic individuals were reported in 42 (1.4%) of 3006 tests and 1436 (3.2%) of 45 327 tests performed on vaccinated and unvaccinated patients, respectively (RR, .44; 95% CI, .33–.60; P &lt; .0001). Compared with unvaccinated patients, risk of asymptomatic SARS-CoV-2 infection was lower among those &gt;10 days after the first dose (RR, .21; 95% CI, .12–.37; P &lt; .0001) and &gt;0 days after the second dose (RR, .20; 95% CI, .09–.44; P &lt; .0001) in the adjusted analysis. Conclusions COVID-19 vaccination with an mRNA-based vaccine showed a significant association with reduced risk of asymptomatic SARS-CoV-2 infection as measured during preprocedural molecular screening. Results of this study demonstrate the impact of the vaccines on reduction in asymptomatic infections supplementing the randomized trial results on symptomatic patients.

AbstractBackgroundNeutropenia is a risk factor for development of infections; however, the direct effect of neutropenia on development of bloodstream infection (BSI) is not known. D‐index, which is area between the neutrophil time curve and a neutrophil count of 0.5 × 109/L, incorporates the combined effect of severity and duration of neutropenia. We aimed to evaluate whether D‐index can be used as a marker for BSI in patients with allogeneic stem cell transplantation.MethodWe conducted a retrospective cohort study of patients undergoing allogeneic stem cell transplantation between January 1, 2005, and September 30, 2015. The primary outcome measure was the development of BSI within 30 days of transplantation.ResultsA total of 714 patients were included in the study of whom 101 developed BSI. Patients with BSI had a significantly higher median D‐index value compared with patients who did not have BSI (4990 vs. 3570, P < .001). As a marker, the performance of the D‐index was similar to that of the duration of profound neutropenia (P = .18) and significantly better than the total duration of neutropenia (P = .001).ConclusionThe D‐index performed better than the total duration of neutropenia as a marker for BSI in patients with allogeneic stem cell transplantation. There was no difference between D‐index and, a more easily calculable indicator, duration of profound neutropenia.

Abstract We performed a case–control study to evaluate an electronic, asynchronous infectious diseases consultative service at 2 rural hospitals within our health system. Patients with consultation via this platform (n = 100) had a significantly decreased odds of death at 30 days compared with propensity-matched controls (n = 300; adjusted odds ratio, 0.3; 95% confidence interval, 0.2–0.7; P = .003).

Abstract Introduction Patients with hematologic malignancies are at higher risk for infection due to the nature of their immunocompromised status, therapy-related complications, and numerous other factors. Multiple myeloma (MM) is the second most common hematologic malignancy after non-Hodgkin's lymphomas. Current literature on bone and joint infections (BJI) in MM is limited to case reports, and this study aims to identify the frequency and characteristics of BJI in MM. Methods We retrospectively reviewed 4607 patients within the MM database at Mayo Clinic from 1/1/2005 through 1/1/2015. A computerized search of the electronic medical record using diagnosis codes, pathology reports, and free text searches, followed by manual chart review, identified 39 unique patients with BJI as depicted in Figure 1. Results Of the 39 patients with BJI and a diagnosis of multiple myeloma, 28/39 (72%) were male, and median age was 70 years-old (range 39-86). 35/39 (90%) had IgG subtype MM, and 21/39 (54%) were in remission from MM while 4/39 (10%) were neutropenic at the time of BJI. 14/39 (36%) occurred after hematopoietic stem cell transplant, and the median duration from transplant to BJI was 45.0 months (range 1.0-88.7). 11/39 (28%) had chronic kidney disease on chart review, and 8/39 (21%) were on corticosteroids. 32/39 (82%) had prior exposure to chemotherapy, and median duration from most recent chemotherapy to BJI was 32 days (range 0-1559). Septic arthritis (9/39, 23%) and osteomyelitis (9/39, 23%) occurred most frequently followed by prosthetic joint infection (PJI) (8/39, 21%). Pathogens were primarily Gram positive organisms (20/39, 51%), and 7/20 (35%) had polymicrobial infections. All patients received culture-guided induction antimicrobial therapy. 27/39 (69%) underwent surgical intervention. Treatment and outcomes by infection can be seen in Figure 1. Of the 5 (13%) treatment failures (TF), 3 (60%) had PJI while 1 (20%) had osteomyelitis with necrotizing fasciitis, and 1 (20%) had septic arthritis. Median time from diagnosis of BJI to TF was 6.3 months (range 0.0-13.5), and none of the TF were neutropenic at the time of BJI. 26/39 (67%) were alive one year after BJI, and at latest chart review, 8/39 (21%) were alive, of whom 7 were treated successfully. Median overall survival from diagnosis of BJI was 34.3 months for all cases. Conclusions BJI are uncommon in MM, and pathogens are similar to patients without MM, though with polymicrobial infections occurring frequently. Treatment is successful in the majority of cases, but PJI appear to have higher TF rates. However, TF may not necessarily correlate with hematologic status or survival. Figure 1 Flowchart of the multiple myeloma study cohort, BJI, treatment, and outcomes MM = Multiple Myeloma; BJI = Bone and Joint Infection; PJI = Prosthetic Joint Infections; VO = Vertebral Osteomyelitis; I&D = Irrigation & Debridement; Abx = Antibiotic Therapy Alone; DAIR = Debridement and Implant Retention; TF = Treatment Failure; CHF = Congestive Heart Failure Figure 1. Flowchart of the multiple myeloma study cohort, BJI, treatment, and outcomes. / MM = Multiple Myeloma; BJI = Bone and Joint Infection; PJI = Prosthetic Joint Infections; VO = Vertebral Osteomyelitis; I&D = Irrigation & Debridement; Abx = Antibiotic Therapy Alone;. / DAIR = Debridement and Implant Retention; TF = Treatment Failure; CHF = Congestive Heart Failure Disclosures Kapoor: Amgen: Research Funding; Takeda: Research Funding; Celgene: Research Funding.

Abstract Background Infectious diseases (ID) consultation is associated with improved outcomes for patients hospitalized with infection. Provision of this service is not practical for many smaller hospitals, particularly critical access facilities. We sought to evaluate the impact of an electronic, asynchronous consultative service (“eConsults”) at two rural hospitals without on-site ID support. Methods Beginning July 2018, ID physicians at Mayo Clinic, Rochester, began performing asynchronous eConsults for patients hospitalized at Mayo Clinic Health System (MCHS) Albert Lea and MCHS Austin Hospitals. The first 100 consecutive patients receiving eConsults (cases) were compared with patients admitted for infection at the same facilities prior to pilot initiation (controls). Cases were matched to controls using 1:3 propensity match based on age, gender, race, and weighted Charlson comorbidity index. The primary outcome was readmission or death within 30 days after hospital discharge. Results Cases (n = 100) were more likely to have been hospitalized in the 6 months prior to the index hospitalization than controls (n = 300) (P < 0.0001). Patients with ID eConsult had a significantly decreased odds of death at 30 days (OR 0.3, 95% CI 0.2–0.7, P = 0.003) and there was a trend toward decreased readmission at 30 days (OR 0.4, 95% CI 0.2–1.1, P = 0.07). The mean length of stay was significantly longer for cases (5.7 days vs. 3.8 days, P =0.003). However, ID eConsult did not occur until 2.6 days into hospitalization, on average. Conclusion ID eConsultation was associated with lower odds of 30-day mortality. The increased length of stay may be mitigated by encouraging ID eConsults earlier during hospitalization. Inpatient ID eConsults represent a high-value proposition for patients and providers and a feasible means of expanding the reach of ID physicians. This novel care delivery model warrants further investigations. Disclosures All authors: No reported disclosures.