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We evaluated the performance of self-collected anterior nasal swab (ANS) and saliva samples compared with healthcare worker-collected nasopharyngeal swab specimens used to test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We used the same PCR diagnostic panel to test all self-collected and healthcare worker-collected samples from participants at a public hospital in Atlanta, Georgia, USA. Among 1,076 participants, 51.9% were men, 57.1% were >50 years of age, 81.2% were Black (non-Hispanic), and 74.9% reported >1 chronic medical condition. In total, 8.0% tested positive for SARS-CoV-2. Compared with nasopharyngeal swab samples, ANS samples had a sensitivity of 59% and saliva samples a sensitivity of 68%. Among participants tested 3-7 days after symptom onset, ANS samples had a sensitivity of 80% and saliva samples a sensitivity of 85%. Sensitivity varied by specimen type and patient characteristics. These findings can help physicians interpret PCR results for SARS-CoV-2.

BACKGROUND Children with sickle cell disease (SCD) are at increased risk for bloodstream infections (BSIs), mainly because of functional asplenia. Immunizations and antibiotic prophylaxis have reduced the prevalence of invasive bacterial infections, but contemporary analysis of BSI in children with SCD is limited. METHODS We conducted a retrospective cohort study of children aged RESULTS There were 2694 eligible patients with 19 902 blood cultures. Excluding repeated cultures and contaminant cultures, there were 156 BSI episodes in 144 patients. The median age at BSI was 7.5 years. The average incidence rate of BSI was 0.89 per 100 person-years (95% CI 0.45–1.32). The most common pathogens were Streptococcus pneumoniae (16.0%), Streptococcus viridans group (9.0%), Escherichia coli (9.0%), Staphylococcus aureus (7.7%), Bordetella holmesii (7.7%), Haemophilus influenzae (7.1%), and Salmonella species (6.4%). Odds of BSI were higher with sickle cell anemia genotypes (odds ratio [OR] 1.88; 95% CI 1.20–2.94) and chronic transfusions (OR 2.66; 95% CI 1.51–4.69) and lower with hydroxyurea (OR 0.57; 95% CI 0.39–0.84). CONCLUSIONS BSI remains a risk for children with SCD. Overall incidence, risk factors, and spectrum of pathogens are important considerations to guide prevention and empirical treatment of suspected infection in SCD.

We aimed to describe frequency of COVID-19 exposure risk factors among patients presenting for medical care at an urban, public hospital serving mostly uninsured/Medicare/Medicaid clients and risk factors associated with SARS-CoV-2 infection. Consenting, adult patients seeking care at a public hospital from August to November 2020 were enrolled in this cross-sectional investigation. Saliva, anterior nasal and nasopharyngeal swabs were collected and tested for SARS-CoV-2 using RT-PCR. Participant demographics, close contact, and activities ≤14 days prior to enrollment were collected through interview. Logistic regression was used to identify risk factors associated with testing positive for SARS-CoV-2. Among 1,078 participants, 51.8% were male, 57.0% were aged ≥50 years, 81.3% were non-Hispanic Black, and 7.6% had positive SARS-CoV-2 tests. Only 2.7% reported COVID-19 close contact ≤14 days before enrollment; this group had 6.79 adjusted odds of testing positive (95%CI = 2.78–16.62) than those without a reported exposure. Among participants who did not report COVID-19 close contact, working in proximity to ≥10 people (adjusted OR = 2.17; 95%CI = 1.03–4.55), choir practice (adjusted OR = 11.85; 95%CI = 1.44–97.91), traveling on a plane (adjusted OR = 5.78; 95%CI = 1.70–19.68), and not participating in an essential indoor activity (i.e., grocery shopping, public transit use, or visiting a healthcare facility; adjusted OR = 2.15; 95%CI = 1.07–4.30) were associated with increased odds of testing positive. Among this population of mostly Black, non-Hispanic participants seeking care at a public hospital, we found several activities associated with testing positive for SARS-CoV-2 infection in addition to close contact with a case. Understanding high-risk activities for SARS-CoV-2 infection among different communities is important for issuing awareness and prevention strategies.

Estimates of the prevalence of SARS-CoV-2 antibodies and factors associated with infection among healthcare personnel (HCP) vary widely. We conducted a serosurvey of HCP at a large public healthcare system in the Atlanta area.All employees of Grady Health System were invited to participate in mid-2020; a volunteer sample of those completing testing was included. Asymptomatic HCP were offered testing for IgG antibody and for SARS-CoV-2 RNA using polymerase chain reaction (PCR). Symptomatic HCP were offered PCR testing. Antibody index values for IgG and cycle threshold values for PCR were evaluated for those with a positive result. An online survey was distributed at the time of testing.624 of 1677 distributed surveys (37.2%) were completed by 608 unique HCP. The majority were female (76.4%) and provided clinical care (70.9%). The most common occupations were clinician (24.8%) and nurse (23.5%). 37 of 608 (6.1%) HCP had detectable IgG. Exposure to a confirmed case of COVID-19 outside of the hospital was associated with detectable IgG (12.8% vs 4.4%, p = 0.02), but exposure to a patient with COVID-19 was not.Among HCP in a large healthcare system, 6.1% had detectable SARS-CoV-2 IgG. Seropositivity was associated with exposures outside of the healthcare setting.

It is unclear how the brain network changed after kidney transplantation (KT). We explored the patterns of large‐scale complex network after KT in end‐stage renal disease (ESRD) patients with resting‐state functional MRI (rs‐fMRI) and diffusion tensor imaging (DTI). Twenty‐one ESRD patients (14 men; mean age, 31.5 ± 9.9 years) scheduled for KT and 17 age‐ and gender‐matched healthy controls (HC) (8 men; mean age, 28.9 ± 7.2 years) were enrolled in this study. Each participant underwent rs‐fMRI and DTI scans in three time points (pre‐KT, 1 and 6 months after KT [for ESRD]). Graph theory analysis was used to characterize the topological properties by using functional and structural network connectivities intergroup correlation analysis was performed between functional/structural MR indexes and clinical markers. Compared with HC, pre‐KT ESRD patients showed an altered topological organization in both functional and structural networks. Compared with pre‐KT, increased node degree and node efficiency were observed for both functional and structural networks at 1 month after KT (all p

While there has been significant progress in the development of rapid COVID-19 diagnostics, as the pandemic unfolds, new challenges have emerged, including whether these technologies can reliably detect the more infectious variants of concern and be viably deployed in non-clinical settings as “self-tests”. Multidisciplinary evaluation of the Abbott BinaxNOW COVID-19 Ag Card (BinaxNOW, a widely used rapid antigen test, included limit of detection, variant detection, test performance across different age-groups, and usability with self/caregiver-administration. While BinaxNOW detected the highly infectious variants, B.1.1.7 (Alpha) first identified in the UK, B.1.351 (Beta) first identified in South Africa, P.1 (Gamma) first identified in Brazil, B.1.617.2 (Delta) first identified in India and B.1.2, a non-VOC, test sensitivity decreased with decreasing viral loads. Moreover, BinaxNOW sensitivity trended lower when devices were performed by patients/caregivers themselves compared to trained clinical staff, despite universally high usability assessments following self/caregiver-administration among different age groups. Overall, these data indicate that while BinaxNOW accurately detects the new viral variants, as rapid COVID-19 tests enter the home, their already lower sensitivities compared to RT-PCR may decrease even more due to user error.

Background Streptococcus pneumoniae infections cause morbidity and mortality worldwide. A rapid, simple diagnostic method could reduce the time needed to introduce definitive therapy potentially improving patient outcomes. Methods We introduce two new methods for diagnosing S. pneumoniae infections by measuring the presence of newly activated, pathogen-specific, circulating Antibody Secreting Cells (ASC). First, ASC were detected by ELISpot assays that measure cells secreting antibodies specific for signature antigens. Second, the antibodies secreted by isolated ASC were collected in vitro in a novel matrix, MENSA (media enriched with newly synthesized antibodies) and antibodies against S. pneumoniae antigens were measured using Luminex immunoassays. Each assay was evaluated using blood from S. pneumoniae and non-S. pneumoniae-infected adult patients. Results We enrolled 23 patients with culture-confirmed S. pneumoniae infections and 24 controls consisting of 12 non-S. pneumoniae infections, 10 healthy donors and two colonized with S. pneumoniae. By ELISpot assays, twenty-one of 23 infected patients were positive, and all 24 controls were negative. Using MENSA samples, four of five S. pneumoniae-infected patients were positive by Luminex immunoassays while all five non-S. pneumoniae-infected patients were negative. Conclusion Specific antibodies produced by activated ASC may provide a simple diagnostic for ongoing S. pneumoniae infections. This method has the potential to diagnose acute bacterial infections.

BACKGROUNDClostridioides difficile infections (CDI) have been a challenging and increasing serious concern in recent years. While early and accurate diagnosis is crucial, available assays have frustrating limitationsOBJECTIVEDevelop a simple, blood-based immunoassay to accurately diagnose patients suffering from active CDI.MATERIALS AND METHODSUninfected controls (n=95) and CDI patients (n=167) were recruited from Atlanta area hospitals. Blood samples were collected from patients within twelve days of a positive CDI test and processed to yield serum and PBMCs cultured to yield medium enriched for newly synthesized antibodies (MENSA). Multiplex immunoassays measured Ig responses to ten recombinant C. difficile antigens.RESULTSSixty-six percent of CDI patients produced measurable responses to C. difficile antigens in their serum or MENSA within twelve days of a positive CDI test. Fifty-two of the 167 CDI patients (31%) were detectable in both serum and MENSA, but 32/167 (19%) were detectable only in MENSA, and 27/167 (16%) were detectable only in serum.DISCUSSIONWe describe the results of a multiplex immunoassay for the diagnosis of ongoing CDI in hospitalized patients. Our assay resolved patients into four categories: MENSA-positive only, serum-positive only, MENSA- and serum-positive, and MENSA- and serum-negative. The MENSA positive-only patients accounted for 30% and may be attributed to nascent antibody secretion in MENSA prior to seroconversion. Conversely, the serum positive-only subset may have been more advanced in their disease course. Immunocompromise and misdiagnosis may have contributed to the 34% of CDI patients who were not identified using MENSA or serum immunoassays.IMPORTANCEWhile there was considerable overlap between patients identified through MENSA and serum, both methods detected additional, unique patients. The combined use of both MENSA and serum to detect CDI patients resulted in the greatest identification of CDI patients. Together, longitudinal analysis of MENSA and serum will provide a more accurate evaluation of successful host humoral immune responses in CDI patients.

Background Geenius HIV 1/2 Supplemental Assay (Geenius; Bio-Rad Laboratories) is the only Food and Drug Administration-approved HIV-1/HIV-2 antibody differentiation test for the second step in the HIV laboratory testing algorithm. We characterized the occurrence of true HIV-1 and HIV-2 infections as well as false results in 6 US clinical laboratories using Geenius. Methods We examined routine HIV testing outcome data from the time the laboratories began using the algorithm with Geenius until September 30, 2017. We calculated the positive predictive value for Geenius HIV-1 and HIV-2 reactivity separately. Results Of 5,046,684 specimens tested, 41,791 had reactive antigen/antibody test results. Most specimens with reactive antigen/antibody results were HIV-1 antibody-positive established infections (n = 32,421), 1,865 of which also had indeterminate HIV-2 bands present. Ninety-three specimens were HIV-2 antibody positive or untypable for HIV-1/HIV-2 antibody. Acute HIV-1 infections were found in 528 specimens; 881 specimens lacked the nucleic acid test to determine the possibility of acute HIV-1 infection. False-positive antigen/antibody test results were present in 7505 specimens. Few specimens (n = 363) had false-positive antigen/antibody results with indeterminate Geenius and negative HIV-1 nucleic acid test results. The positive predictive values of Geenius reactivity were 99.4% for HIV-1 and 4.3% for HIV-2. Conclusions Routine testing using the laboratory testing algorithm with Geenius resulted in most specimens resolving as HIV negative or HIV-1 positive. The occurrence of indeterminate HIV-2 bands with a Geenius final assay interpretation of HIV-1 positive was more common than true HIV-2 infections. Reporting indeterminate HIV-2 results in this situation may cause confusion with interpreting HIV infection status.

Self-collected specimens can expand access to SARS-CoV-2 testing. At a large inner-city hospital 1,082 participants self-collected saliva and anterior nasal swab (ANS) samples before healthcare workers collected nasopharyngeal swab (NPS) samples on the same day. To characterize patient preferences for self-collection, this investigation explored ability, comfort, and ease of ANS and saliva self-collection for SARS-CoV-2 testing along with associated patient characteristics, including medical history and symptoms of COVID-19. With nearly all participants successfully submitting a specimen, favorable ratings from most participants (at least >79% in ease and comfort), and equivocal preference between saliva and ANS, self-collection is a viable SARS-CoV-2 testing option.

The association between human immunodeficiency virus (HIV) infection and tuberculosis (TB) mortality has been studied extensively, but the impact of HIV on other clinically relevant aspects of TB care such as TB drug-related adverse events (AEs), hospital readmissions, and TB treatment duration is less well characterized. We describe the association of HIV infection with TB clinical complexities and outcomes in a high HIV prevalence cohort in the United States. This is a retrospective cohort study among patients treated for culture-confirmed TB between 2008 and 2015 at an inner-city hospital in Atlanta, GA. Univariate analysis was used to estimate association of HIV with TB treatment interruption due to AEs, hospital readmissions, and treatment duration. Final unfavorable TB treatment outcome was defined as death, loss to follow-up, or recurrent TB. Logistic regression modeling was used to estimate association of HIV with final unfavorable outcomes. Among 274 patients with TB, 96 (35%) had HIV coinfection. HIV-positive patients had more TB treatment interruptions due to AE (34% vs. 15%), were more likely to have a hospital readmission (50% vs. 21%), and received longer TB treatment (9.9 months vs. 8.8 months) compared to HIV-negative patients (p

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative option for treatment of some malignant and non-malignant hematological diseases. However, post-HSCT patients are severely immunocompromised and susceptible to viral infections, which are a major cause of morbidity and mortality. Although antiviral agents are now available for most types of viral infections, they are not devoid of side effects and their efficacy is limited when there is no concomitant antiviral immune reconstitution. In recent decades, adoptive transfer of viral-specific T cells (VSTs) became an alternative treatment for viral infection after HSCT. However, two major issues are concerned in VST transfer: the risk of GVHD and antiviral efficacy. We report an exhaustive review of the published studies that focus on prophylactic and/or curative therapy by donor VST transfer for post-HSCT common viral infections. A low incidence of GVHD and a good antiviral efficacy was observed after adoptive transfer of VSTs from HSCT donor. Viral-specific T-cell transfer is a promising approach for a broad clinical application. Nevertheless, a randomized controlled study in a large cohort of patients comparing antiviral treatment alone to antiviral treatment combined with VSTs is still needed to demonstrate efficacy and safety.

BACKGROUND Children with sickle cell disease (SCD) are at increased risk for invasive infection with encapsulated bacteria. Antibiotic prophylaxis and immunizations against Streptococcus pneumoniae and Haemophilus influenzae type b (Hib) have decreased the overall incidence of invasive infections and have shifted distribution of serotypes causing disease toward those not covered by immunizations. We sought to determine the current incidence of invasive H. influenzae infections in children with SCD and to describe the clinical features and management of these infections. METHODS Microbiology reports of a large pediatric tertiary care center were reviewed to identify all isolates of H. influenzae detected in sterile body fluid cultures from January 1, 2010 to December 31, 2017. Results were compared with the center's comprehensive clinical database of all children with SCD to identify all cases of children ages 0 to18 years with SCD with invasive H. influenzae disease for the same time period. RESULTS We captured 2444 patients with SCD, with 14,336 person-years. There were eight episodes of H. influenzae bacteremia in seven children with SCD (five type f, two non-typable, one type a). Most episodes (7 of 8) were in children

Campylobacteriosis is an infectious gastrointestinal disease caused by Campylobacter spp. In most cases, it is either underdiagnosed or underreported due to poor diagnostics and limited databases. Several DNA-based molecular diagnostic techniques, including 16S ribosomal RNA (rRNA) sequence typing, have been widely used in the species identification of Campylobacter. Nevertheless, these assays are time-consuming and require a high quality of bacterial DNA. Matrix-assisted laser desorption ionization (MALDI) time-of-flight (TOF) MS is an emerging diagnostic technology that can provide the rapid identification of microorganisms by using their intact cells without extraction or purification. In this study, we analyzed 24 American Type Culture Collection reference isolates of 16 Campylobacter spp. and five unknown clinical bacterial isolates for rapid identification utilizing two commercially available MADI-TOF MS platforms, namely the bioMérieux VITEK® MS and Bruker Biotyper systems. In addition, 16S rRNA sequencing was performed to confirm the species-level identification of the unknown clinical isolates. Both MALDI-TOF MS systems identified the isolates of C. jejuni, C. coli, C. lari, and C. fetus. The results of this study suggest that the MALDI-TOF MS technique can be used in the identification of Campylobacter spp. of public health importance.

The physiochemical stem cell microenvironment regulates the delicate balance between self-renewal and differentiation. The three-dimensional assembly of stem cells facilitates cellular interactions that promote morphogenesis, analogous to the multicellular, heterotypic tissue organization that accompanies embryogenesis. Therefore, expansion and differentiation of stem cells as multicellular aggregates provides a controlled platform for studying the biological and engineering principles underlying spatiotemporal morphogenesis and tissue patterning. Moreover, three-dimensional stem cell cultures are amenable to translational screening applications and therapies, which underscores the broad utility of scalable suspension cultures across laboratory and clinical scales. In this review, we discuss stem cell morphogenesis in the context of fundamental biophysical principles, including the three-dimensional modulation of adhesions, mechanics, and molecular transport and highlight the opportunities to employ stem cell spheroids for tissue modeling, bioprocessing, and regenerative therapies.

Background Previous studies showed improvement in heart function by injecting bone marrow mesenchymal stem cells (BMSCs) after AMI. Emerging evidence suggested that both the number and function of BMSCs decline with ageing. We designed a randomized, controlled trial to further investigate the safety and efficacy of this treatment. Methods Patients with ST-elevation AMI undergoing successful reperfusion treatment within 12hours were randomly assigned to receive an intracoronary infusion of BMSCs (n=21) or standard medical treatment (n=22) (the numbers of patients were limited because of the complication of coronary artery obstruction). Results There is a closely positive correlation of the number and function of BMSCs vs. the cardiac function reflected by LVEF at baseline (r=0.679, P=0.001) and at 12-month follow-up (r=0.477, P=0.039). Six months after cell administration, myocardial viability within the infarct area by 18-FDG SPECT was improved in both groups compared with baseline, but no significant difference in the BMSCs compared with control groups (4.0±0.4% 95%CI 3.1–4.9 vs. 3.2±0.5% 95%CI 2.1–4.3, P=0.237). 99mTc-sestamibi SPECT demonstrated that myocardial perfusion within the infarct area in the BMSCs did not differ from the control group (4.4±0.5% 95%CI 3.2–5.5 vs. 3.9±0.6% 95%CI 2.6–5.2, P=0.594). Similarly, LVEF after 12 and 24months follow-up did not show any difference between the two groups. In the BMSCs group, one patient suffered a serious complication of coronary artery occlusion during the BMSCs injection procedure. Conclusions The clinical benefits of intracoronary injection of autologous BMSCs in acute STEMI patients need further investigation and reevaluation.

This case report discusses a patient with sickle cell disease who presented with fungemia from Pichia anomala (teleomorph: Candida pelliculosa). The organism was identified as P. anomala by MALDI-TOF VITEK mass spectrometry and VITEK 2 yeast identification card. Pichia anomala should be considered in sickle cell patients with recurrent fungemia.

Multidrug-resistant tuberculosis (MDR TB), defined by resistance to the 2 most effective first-line drugs, isoniazid and rifampin, is on the rise globally and is associated with significant morbidity and mortality. Despite the increasing availability of novel rapid diagnostic tools for Mycobacterium tuberculosis (Mtb) drug susceptibility testing, the clinical applicability of these methods is unsettled. In this study, the mechanisms of action and resistance of Mtb to isoniazid and rifampin, and the utility, advantages and limitations of the available Mtb drug susceptibility testing tools are reviewed, with particular emphasis on molecular methods with rapid turnaround including line probe assays, molecular beacon-based real-time polymerase chain reaction and pyrosequencing. The authors conclude that neither rapid molecular drug testing nor phenotypic methods are perfect in predicting Mtb drug susceptibility and therefore must be interpreted within the clinical context of each patient.

We sought to define the prevalence of blaZ gene types and the inoculum effect to cefazolin among methicillin-susceptible Staphylococcus aureus (MSSA) bloodstream infections. The blaZ gene was present in 142/185 (77%) isolates. A total of 50 (27%) isolates had a ≥4-fold increase in the cefazolin MIC from a standard to a high inoculum, and 8 (4%) demonstrated a nonsusceptible cefazolin MIC, all type A blaZ strains. The efficacy of cefazolin in the presence of the inoculum effect requires further study.

Mesenchymal stem cells (MSCs) are regarded as a potential autologous source for cartilage repair, because they can differentiate into chondrocytes by transforming growth factor-beta (TGF-β) treatment under the 3-dimensional (3-D) culture condition. In addition to these molecular and biochemical methods, the mechanical regulation of differentiation and matrix formation by MSCs is only starting to be considered. Recently, mechanical loading has been shown to induce chondrogenesis of MSCs in vitro. In this study, we investigated the effects of a calibrated agitation on the chondrogenesis of human bone MSCs (MSCs) in a 3-D alginate culture (day 28) and on the maintenance of chondrogenic phenotypes. Biomechanical stimulation of MSCs increased: (i) types 1 and 2 collagen formation; (ii) the expression of chondrogenic markers such as COMP and SOX9; and (iii) the capacity to maintain the chondrogenic phenotypes. Notably, these effects were shown without TGF-β treatment. These results suggest that a mechanical stimulation could be an efficient method to induce chondrogenic differentiation of MSCs in vitro for cartilage tissue engineering in a 3-D environment. Additionally, it appears that MSCs and chondrocyte responses to mechanical stimulation are not identical.

In 2010 the Clinical and Laboratory Standards Institute (CLSI) lowered the susceptibility breakpoints of some cephalosporins and aztreonam for Enterobacteriaceae and eliminated the need to perform screening for extended-spectrum β-lactamases (ESBLs) and confirmatory tests. The aim of this study was to determine how many ESBL-producing strains of three common species of Enterobacteriaceae test susceptible using the new breakpoints. As determined with the CLSI screening and confirmatory tests, 382 consecutive ESBL-producing strains were collected at Huashan Hospital between 2007 and 2008, including 158 strains of Escherichia coli , 164 of Klebsiella pneumoniae , and 60 of Proteus mirabilis . Susceptibility was determined by the CLSI agar dilution method. CTX-M-, TEM-, and SHV-specific genes were determined by PCR amplification and sequencing. bla CTX-M genes alone or in combination with bla SHV were present in 92.7% (354/382) of these ESBL-producing strains. Forty-two (25.6%) strains of K. pneumoniae harbored SHV-type ESBLs alone or in combination. No TEM ESBLs were found. Utilizing the new breakpoints, all 382 strains were resistant to cefazolin, cefotaxime, and ceftriaxone, while 85.0 to 96.7% of P. mirabilis strains tested susceptible to ceftazidime, cefepime, and aztreonam, 41.8 to 45.6% of E. coli strains appeared to be susceptible to ceftazidime and cefepime, and 20.1% of K. pneumoniae were susceptible to cefepime. In conclusion, all ESBL-producing strains of Enterobacteriaceae would be reported to be resistant to cefazolin, cefotaxime, and ceftriaxone by using the new CLSI breakpoints, but a substantial number of ESBL-containing P. mirabilis and E. coli strains would be reported to be susceptible to ceftazidime, cefepime, and aztreonam, which is likely due to the high prevalence of CTX-M type ESBLs.

Histoplasmosis is known to be an AIDS-associated infection, with scattered areas of endemicity throughout the world. Although the Atlanta, GA, metropolitan area is not a highly endemic area, a significant number of cases have been noted at our institution in recent years. Cases of histoplasmosis over a 4-year period were reviewed. All 27 patients (100%) were HIV infected. Thirty percent of patients with histoplasmosis were from Latin American countries. Patients from Latin America were younger than patients from the United States, tended to be more likely to have proven disease, and were exclusively male. Patients with proven disease had significantly higher urine histoplasma antigen levels, lower platelets counts, and lower neutrophil counts than patients with probable disease. The majority of patients survived after treatment with antifungals and initiation of antiretroviral therapy. Histoplasmosis is thus an important consideration in the workup of patients with advanced HIV in nonendemic areas of the United States.

Herpes simplex virus (HSV) encephalitis has a predilection for the temporal and frontal lobes but occasionally affects the brainstem. We describe a patient who developed HSV brainstem encephalitis that progressed to quadriplegia. Using MEDLINE, we conducted a comprehensive review of other published cases of HSV brainstem encephalitis. Twenty-four published cases of HSV brainstem encephalitis met our inclusion criteria. The mean age was 41.4 years (range 18-71). HSV-1 was the etiologic agent in 79% of reported HSV brainstem encephalitis cases, and HSV-2 accounted for 21% of cases. Infection was limited to the brainstem in 29% of cases and multi-focal, including the brainstem, in 71%. Common manifestations of HSV brainstem encephalitis included neuro-ophthalmologic findings (81%), cranial nerve deficits (69%), and fever (69%). Quadriplegia, as occurred in our patient, was an unusual finding (19%). The mortality rate of HSV brainstem encephalitis was 41%. Intravenous acyclovir showed a beneficial effect on mortality (75% vs. 22%, p = 0.06). HSV brainstem encephalitis is a distinct type of HSV encephalitis. With the increasing use of HSV-PCR, more cases of HSV brainstem encephalitis may be identified. A greater recognition of this syndrome will help better define its optimal treatment and prognosis.

Background: Sexually transmissible infections (STI) have been variably associated with increased risks of prostate cancer, largely in case-control studies. Methods: In the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, we examined risk of prostate cancer in relation to serum antibodies to Chlamydia trachomatis, human papillomavirus-16 and -18, herpes simplex virus-2, cytomegalovirus, and human herpesvirus-8 in 868 cases (765 Whites and 103 Blacks) and 1,283 controls matched by race, age, time since initial screening, and year of blood draw; all blood samples were collected at least 1 year before prostate cancer diagnosis, except for 43 Black cases. We also assessed risk associated with self-reported history of syphilis and gonorrhea. Results: Prevalences of the 7 STIs among controls were weakly correlated, and all were more frequent among Blacks than Whites, except for human herpesvirus-8. Among Whites, prostate cancer risk was not significantly associated with the individual infections or with their number (Ptrend = 0.1); however, men with one or more STI had slightly higher risk (odds ratio, 1.3; 95% confidence interval, 1.0-1.6). Among Blacks, excess risk was associated with IgA antibody to C. trachomatis (odds ratio, 2.1; 95% confidence interval, 1.2-3.6). Conclusion: This large prospective study of prostate cancer shows no consistent association with specific STIs and a borderline association with any versus none. Whether a shared response or correlated infection not directly measured underlies the weak association requires further study. (Cancer Epidemiol Biomarkers Prev 2008;17(9):2374–81)

Both chondrocytes and mensenchymal stem cells (MSCs) are the most used cell sources for cartilage tissue engineering. However, monolayer expansion to obtain sufficient cells leads to a rapid chondrocyte dedifferentiation and a subsequent ancillary reduced ability of MSCs to differentiate into chondrocytes, thus limiting their application in cartilage repair. The aim of this study was to investigate the influence of the monolayer expansion on the immunophenotype and the gene expression profile of both cell types, and to find the appropriate compromise between monolayer expansion and the remaining chondrogenic characteristics. To this end, human chondrocytes, isolated enzymatically from femoral head slice, and human MSCs, derived from bone marrow, were maintained in monolayer culture up to passage 5. The respective expressions of cell surface markers (CD34, CD45, CD73, CD90, CD105, CD166) and several chondrogenic-related genes for each passage (P0-P5) of those cells were then analyzed using flow cytometry and quantitative real-time PCR, respectively. Flow cytometry analyses showed that, during the monolayer expansion, some qualitative and quantitative regulations occur for the expression of cell surface markers. A rapid increase in mRNA expression of type 1 collagen occurs whereas a significant decrease of type 2 collagen and Sox 9 was observed in chondrocytes through the successive passages. On the other hand, the expansion did not induced obvious change in MSCs gene expression. In conclusion, our results suggest that passage 1 might be the up-limit for chondrocytes in order to achieve their subsequent redifferentiation in 3D scaffold. Nevertheless, MSCs could be expanded in monolayer until passage 5 without loosing their undifferentiated phenotypes.

Young pregnant women are a group at particularly high risk of STDs.1,2 In a systematic literature review of sexual risk and STDs among pregnant teenagers and those who have given birth, STD incidence was 19−39% during pregnancy, and 14−39% between six and 10 months postpartum. In addition, adolescent mothers were twice as likely as their nulliparous peers to acquire an STD during a 12-month period. Furthermore, 78−88% of pregnant women engaged in sex without condoms during pregnancy, and pregnant women were only about one-fifth as likely as nonpregnant women to use condoms.3 Current guidelines from the Centers for Disease Control and Prevention (CDC) recommend STD screening for all high-risk women-usually defined as those younger than 25 and those with multiple or new partners.4 Frequently, screening for all high-risk pregnant women occurs only during initial prenatal care visits, so an infection that is acquired later in pregnancy may go undetected. Some clinics retest women who are deemed high-risk (e.g., those testing STD-positive at their initial visit) or exhibit symptoms; however, testing procedures differ from clinic to clinic, and screening behavior can vary by provider.5 In addition, because an STD diagnosis and treatment are not enough to have long-term effects on risky behavior,6 an emphasis on prevention is necessary to achieve long-term risk reduction. Prevention programs integrated with prenatal care can capitalize on women's motivation to have a healthy pregnancy and child. HIV and other STD prevention programs have been successfully integrated in psychiatric care, drug treatment and palliative medicine settings.7–9 This model for prevention could be extended to include prenatal care. For interventions to be most effective in clinical settings, they should be easy to implement and tailored to meet the needs and risks of particular patients. Thus, it may be beneficial to identify subgroups of women at varying risk of STDs during pregnancy, and implement treatment, care and prevention programs that best meet the needs of those individuals. To successfully do this, providers need to go beyond the typical characteristics obtained during prenatal care assessments. A 2002 Institute of Medicine report and more recent research syntheses suggest that ecological approaches to health, and to STD prevention, are particularly useful and needed.3,10,11 Ecological systems theory emphasizes that factors from many levels (e.g., individual, dyad, family and community) can influence health.3,10–12 The few studies on young people's sexual activity that have included factors from many levels have shown that dyad, family and community factors independently contribute to risk behavior above and beyond individual factors.13–15 In addition to using primarily individual-level predictors, most studies that have tried to estimate STD risk have used standard analytic techniques (e.g., logistic regression). However, these methods are limited because they assume primarily linear relationships between the predictors and outcomes that may not be realistic in applied settings. Furthermore, results from these techniques (e.g., odds ratios in logistic regression) are difficult to translate into clinical practice and policy.16 Classification tree analysis, also called recursive partitioning, avoids the limitations associated with logistic regression and other standard methods. The technique uses a set of predictors to create subgroups of individuals that vary in risk for the main outcome of interest, ultimately producing a user-friendly classification tree that can be employed to guide care, treatment and prevention efforts in clinical settings. For example, in a study of young adults at an STD clinic, several subgroups were classified as having a high STD risk because of particular behavioral and emotional factors (e.g., one group felt bad about themselves after having sex and had sex to relieve tension; one group fell bad about themselves after having sex and had sex to get back at someone).17 Use of classification tree analysis has been documented in the health care and managed care literature,18 and has been used in many clinical and medical settings to identify high-risk patients and to help create clinical guidelines.19–23 Clinicians often use informal decision trees when making clinical decisions. On the basis of a complex interaction of medical, demographic and behavioral factors, clinicians determine the likelihood of disease outcomes and often use these patient characteristics to guide care and treatment decisions (e.g., if a woman is having risky sex and is younger than 25, the clinician may screen for STDs because past experience suggests that the patient is at risk). The purpose of this study is to use individual, dyad, and family- and community-level characteristics to develop a clinically relevant classification tree that will help identify women who are at risk of acquiring an STD during pregnancy and will provide a formal decision-making structure for STD prevention, treatment and care.

Background Whether community-associated methicillin-resistant Staphylococcus aureus (MRSA) genotypes (e.g., USA300) are a major cause of bloodstream infections (BSIs) and health care-associated infections has been poorly defined. Methods Consecutive MRSA isolates recovered from patients with BSIs were prospectively collected at an urban public hospital. Molecular typing studies were performed. Prevalence and risk factors for the MRSA USA300 genotype were assessed. Results One hundred thirty-two cases of MRSA BSI were documented over 7.5 months in 2004 (incidence, 6.79 per 1000 admissions); 116 isolates were available for genotyping. Characteristics of the 116 evaluable cases included: a mean age 47 years; 62% were male, 82% were African American, and 22% were HIV seropositive. The crude in-hospital mortality rate was 22%. In 107 cases (92%), there was contact with a health care facility within the year prior to infection, and a nosocomial infection (defined as positive blood culture results obtained >48 h after admission) occurred in 49 cases (42%). PFGE demonstrated that 39 (34%) of the 116 isolates were the MRSA USA300 genotype; 34 (29%) were USA100; 42 (36%) were USA500; and 1 (1%) was USA800. MRSA USA300 accounted for 28% of health care-associated BSIs and 20% of nosocomial MRSA BSIs. In multivariate analysis, isolation of the USA300 genotype was associated with injectiondrug use (OR, 3.67; 95% CI, 1.10-12.28) and skin and soft tissue infection (OR, 4.26; 95% CI, 1.08-16.84). Patients who resided in long-term care facilities (OR, 0.09; 95% CI, 0.01-0.82) and those who were treated with antimicrobials in the prior year were less likely to have MRSA USA300 genotype recovered (OR, 0.10; 95% CI, 0.02-0.49). Conclusions MRSA USA300 genotype, the predominant cause of community-associated MRSA infections in our area (Atlanta, GA), has now emerged as a significant cause of health care-associated and nosocomial BSI. MRSA USA300 as a nosocomial pathogen presents new challenges to infection control programs.

Introduction The Centers for Disease Control and Prevention has recommended using a nucleic acid amplification test (NAAT) for diagnosing pulmonary tuberculosis (TB) but there is a lack of data on NAAT cost-effectiveness. Methods We conducted a prospective cohort study that included all patients with an AFB smear-positive respiratory specimen at Grady Memorial Hospital in Atlanta, GA, USA between January 2002 and June 2008. We determined the sensitivity, specificity, and positive and negative predictive value of a commercially available and FDA-approved NAAT (amplified MTD, Gen-Probe) compared to the gold standard of culture. A cost analysis was performed and included costs related to laboratory tests, hospital charges, anti-TB medications, and contact investigations. Average cost per patient was calculated under two conditions: (1) using a NAAT on all AFB smear-postive respiratory specimens and (2) not using a NAAT. One-way sensitivity analyses were conducted to determine sensitivity of cost difference to reasonable ranges of model inputs. Results During a 6 1/2 year study period, there were 1,009 patients with an AFB smear-positive respiratory specimen at our public urban hospital. We found the NAAT to be highly sensitive (99.6%) and specific (99.1%) on AFB smear-positive specimens compared to culture. Overall, the positive predictive value (PPV) of an AFB smear-positive respiratory specimen for culture-confirmed TB was 27%. The PPV of an AFB smear-positive respiratory specimen for culture-confirmed TB was significantly higher for HIV-uninfected persons compared to those who were HIV-seropositive (152/271 [56%] vs. 85/445 [19%]; RR = 2.94, 95% CI 2.36–3.65, p

Objectives Nosocomial pathogens such as Acinetobacter baumannii are a growing public health threat, due in part to their increasing resistance to antibiotics. Since some strains are resistant to all available antibiotics, novel therapies are urgently needed. Plasmablasts are short-lived B cells found in the blood that can be collected and harnessed to produce therapeutic antibodies. We set out to determine whether plasmablasts are induced during infection with A. baumannii and other nosocomial pathogens. Methods We obtained blood samples from patients infected with antibiotic-resistant nosocomial pathogens, and analysed their plasmablast response by flow cytometry. Results We observed a strong induction of plasmablasts in patients with antibiotic-resistant A. baumannii infection. Furthermore, plasmablasts were also induced in response to other drug-resistant nosocomial pathogens. Conclusions These data suggest that plasmablasts may be broadly harnessed to develop therapeutic antibodies to combat otherwise untreatable antibiotic-resistant infections.

Clinical efforts to repair cartilage defects delivering cells or engineered cartilage implants into the lesions have met with limited success. This study used a critical-size chondral defect model in immunocompromised rat xiphoid cartilage to test whether endogenous chondrogenesis could be achieved using human bone matrix scaffolds to deliver human cartilage particles and/or a variant isoform of fibroblast growth factor-2 (FGF2-variant). Seventy-two male athymic RNU rats were enrolled in this study with eight rats per experimental group. Decellularized and demineralized human bone matrix scaffolds loaded with human articular cartilage particles or heat-inactivated cartilage particles were combined with different doses of the FGF2-variant. Scaffolds were implanted into 3-mm-diameter critical-size defects prepared using a biopsy punch through the center of the xiphoid. The samples were evaluated 28 days postsurgery using X-ray, equilibrium partitioning of ionic contrast microcomputed tomography, and safranin O-stained histological sagittal sections. Scaffolds containing cartilage particles plus the FGF2-variant induced dose-dependent increases in the formation of neocartilage (p0.05), which was distributed homogeneously throughout the defects in comparison to scaffolds containing only the FGF2-variant. These effects were less pronounced when scaffolds with heat-inactivated cartilage particles were used. These results demonstrate that endogenous repair of chondral defects can be achieved in the absence of exogenous cells or bone marrow, suggesting that a similar approach may be successful for treating chondral lesions clinically.

Background: The etiology and outcomes of blood-stream infections (BSI) among paediatric patients is not well described in resource-limited countries including Georgia. Methodology: Patients with positive blood cultures at the largest paediatric hospital in the country of Georgia were identified by review of the medical and laboratory records of patients who had blood for cultures drawn between January 2004 and June 2006. Results: Of 1,693 blood cultures obtained during the study period, 338 (20%) were positive; of these, 299 were included in our analysis. The median age was 14 days from a range of 2 days to 14 years of which 178 (60%) were male; 53% of the patients with a positive culture were admitted to the Neonatal Intensive Care Unit (NICU). Gram-negative bacilli (GNB) represented 165 (55%) of 299 cultures. Further speciation of 135 (82%) of 165 Gram-negative rod (GNR) was not possible because of lack of laboratory capacity. Overall, mortality was 30% (90 of 299). Among the 90 children who died, 80 (89%) were neonates and 68 (76%) had BSI caused by Gram-negative organisms. In multivariate analysis, independent risk factors for in-hospital mortality included an age of less than 30 days (OR=4.00, 95% CI 1.89-8.46) and having a positive blood culture for a Gram-negative BSI (OR = 2.38, 95% CI 1.32-4.29). Conclusions: A high mortality rate was seen among children, particularly neonates, with positive blood cultures at the largest paediatric hospital in Georgia. Because of limited laboratory capacity, microbiological identification of common organisms known to cause BSI in children was not possible and susceptibility testing was not performed. Improving the infrastructure of diagnostic microbiology laboratories in countries with limited resources is critical in order to improve patient care and clinical outcomes, and from a public health standpoint, to improve surveillance activities.

Background.A cluster of patients with respiratory cultures positive for Pseudomonas aeruginosa with a unique antibiogram was observed during June and July 2007 at a 1,000-bed urban teaching hospital in Atlanta, Georgia. These P. aeruginosa isolates were recovered from bronchoscopically obtained specimens.Methods.A cross-sectional study was performed to assess whether the cluster was associated with exposure to a particular bronchoscope (B1); cultures from specimens from the bronchoscopes and the environment were obtained, and the P. aeruginosa isolate type was determined using pulsed-field gel electrophoresis (PFGE). Records of patients exposed to B1 during the cluster period were reviewed.Results.Twelve patients with a culture positive for P. aeruginosa with the unique susceptibility pattern were identified in June-July 2007. No cases were documented from March 1 through May 31, 2007. Culture specimens obtained from B1 after high-level disinfection revealed P. aeruginosa, prompting removal of B1 from service on July 23, 2007. No cases occurred after that date. Eleven (55%) of 20 patients who were exposed to Bl during the cluster period had a culture positive for P. aeruginosa, compared with 1 (2%) of 53 patients who were exposed to other bronchoscopes (P < .001). PFGE patterns for P. aeruginosa isolates obtained from case patients and from B1 were identical. An engineering evaluation of B1 documented several internal damages. Two (10.5%) of 19 patients exposed to Bl during the cluster period may have developed P. aeruginosa infection following exposure to B1.Conclusions.An outbreak or pseudo-outbreak of P. aeruginosa infection occurred in association with use of a damaged bronchoscope. Periodic engineering maintenance may be needed to prevent bronchoscope contamination that is resistant to high-level disinfection.

After Hurricane Katrina, 50 patients were evacuated to Grady Memorial Hospital in Atlanta, Georgia, with limited medical records. The infection control department ordered contact precautions for 16 Patients. Surveillance cultures performed on admission identified colonization with multidrug-resistant (MDR) bacteria in 9 patients (18%). Presence of a wound was the strongest predictor for MDR colonization. More data are needed to reliably predict MDR bacterial colonization.

Ex vivo expansion of hematopoietic stem cells (HSC) can help reduce cytopenia following transplantation, especially in NHL patients whose BM is deficient because of extensive chemotherapy. We have previously reported that human umbilical vein endothelial cells (HUVEC) can contribute to improved PBPC expansion when used in co-culture with CD34(+) cells.We evaluated the roles of direct HUVEC CD34(+) contact and HUVEC-produced soluble factors. We cultured CD34(+) PBPC harvested from NHL patients in four different conditions: (1) liquid culture without HUVEC; (2) co-culture in contact with HUVEC; (3) co-culture with HUVEC but without direct contact; (4) liquid culture with HUVEC-conditioned medium (CM). Thrombopoietin (Tpo), Flk2Flt3 ligand (FL) and c-kit ligand (KL) with or without rhIL-6 were added to these four culture conditions.Our results showed that HUVEC co-culture or addition of HUVEC-CM to Tpo, FL and KL (TFK) improved CD34(+) PBPC expansion compared with liquid culture, as determined by total viable nucleated cells (TNC), colony-forming cell assay (CFC) and week-6 cobblestone area-forming cells (Wk-6 CAFC) expansions. Non-contact culture led to similar PBPC expansion as contact co-culture; moreover, HUVEC-CM improved PBPC expansion. However, when rhIL-6 was added to HUVEC-CM with TFK, no significant difference was observed. Finally, high quantities of IL-6 were detected in HUVEC-CM and addition of anti-IL-6 Ab inhibited the positive effect of HUVEC on PBPC expansion. Our results thus suggest that HUVEC may improve PBPC expansion, at least through IL-6 secretion.

Background Foreign-born, HIV-infected persons are at risk for sub-clinical parasitic infections acquired in their countries of origin. The long-term consequences of co-infections can be severe, yet few data exist on parasitic infection prevalence in this population. Methodology/Principal Findings This cross-sectional study evaluated 128 foreign-born persons at one HIV clinic. We performed stool studies and serologic testing for strongyloidiasis, schistosomiasis, filarial infection, and Chagas disease based on the patient's country of birth. Eosinophilia and symptoms were examined as predictors of helminthic infection. Of the 128 participants, 86 (67%) were male, and the median age was 40 years; 70 were Mexican/Latin American, 40 African, and 18 from other countries or regions. Strongyloides stercoralis antibodies were detected in 33/128 (26%) individuals. Of the 52 persons from schistosomiasis-endemic countries, 15 (29%) had antibodies to schistosome antigens; 7 (47%) had antibodies to S. haematobium, 5 (33%) to S. mansoni, and 3 (20%) to both species. Stool ova and parasite studies detected helminths in 5/85 (6%) persons. None of the patients tested had evidence of Chagas disease (n = 77) or filarial infection (n = 52). Eosinophilia >400 cells/mm3 was associated with a positive schistosome antibody test (OR 4.5, 95% CI 1.1–19.0). The only symptom significantly associated with strongyloidiasis was weight loss (OR 3.1, 95% CI 1.4–7.2). Conclusions/Significance Given the high prevalence of certain helminths and the potential lack of suggestive symptoms and signs, selected screening for strongyloidiasis and schistosomiasis or use of empiric antiparasitic therapy may be appropriate among foreign-born, HIV-infected patients. Identifying and treating helminth infections could prevent long-term complications., Author Summary Undiagnosed and untreated parasitic infections can have severe consequences for human immunodeficiency virus (HIV)-infected persons. An estimated 2 billion people worldwide are infected with soil-transmitted helminths and schistosomiasis, yet there are few data on the prevalence in HIV-infected immigrants to more developed countries. This information could help clinicians determine what testing is needed and what signs or symptoms to expect. We performed serologic, stool, and urine testing for selected parasites in 128 foreign-born persons receiving care at an HIV clinic in Atlanta, Georgia. We found that 26% had serologic evidence of infection with Strongyloides stercoralis and 29% had serologic evidence of schistosomiasis. Because these were likely chronic processes, symptoms and signs were often absent; only weight loss was significantly associated with strongyloidiasis. High eosinophil counts were also associated with parasitic infection. This study suggests the need for targeted screening of foreign-born, HIV-infected persons for parasitic infections (mainly strongyloidiasis and schistosomiasis) or the use of empiric antiparasitic therapy, particularly among those with unexplained eosinophilia. Although there are established guidelines for screening of refugees, health care providers should consider the risk of these organisms in patients who have entered the United States through other pathways.