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High prevalence of Group B Streptococcus colonization among pregnant women in Amman, Jordan
Clouse, Kate; Shehabi, Asem; Suleimat, Abel Mani; Faouri, Samir; Khuri-Bulos, Najwa; Al Jammal, Abeer; Chappell, James; Fortner, Kimberly B; Chamby, Anna B; Randis, Tara M; Ratner, Adam J; Aronoff, David M; Halasa, Natasha
BACKGROUND:Little is known of the burden of Group B Streptococcus (GBS) colonization among pregnant women in Jordan. We conducted a pilot study to determine the prevalence of GBS among pregnant women in Amman, Jordan, where GBS testing is not routine. We also explored GBS serotypes and the performance of a rapid GBS antigen diagnostic test. METHODS:We collected vaginal-rectal swabs from women who presented for labor and delivery at Al-Bashir Hospital. Three methods were used to identify GBS: Strep B Rapid Test (Creative Diagnostics), blood agar media (Remel) with confirmed with BBL Streptocard acid latex test (Becton Dickinson), and CHROMagar StrepB (Remel). Results were read by a senior microbiologist. We defined our gold standard for GBS-positive as a positive blood agar culture confirmed by latex agglutination and positive CHROMagar. PCR testing determined serotype information. Demographic and clinical data were also collected. RESULTS:In April and May 2015, 200 women were enrolled with a median age of 27 years (IQR: 23-32); 89.0% were Jordanian nationals and 71.9% completed secondary school. Median gestational age was 38 weeks (IQR: 37-40); most women reported prenatal care (median 9 visits; IQR: 8-12). Median parity was 2 births (IQR: 1-3). Pre-pregnancy median BMI was 24.1 (IQR: 21.5-28.0) and 14.5% reported an underlying medical condition. Obstetric complications included gestational hypertension (9.5%), gestational diabetes (6.0%), and UTI (53.5%), of which 84.5% reported treatment. Overall, 39 (19.5%) of women were GBS-positive on blood agar media and CHROMagar, while 67 (33.5%) were positive by rapid test (36% sensitivity, 67% specificity). Serotype information was available for 25 (64%) isolates: III (48%), Ia (24%), II (20%), and V (8%). No demographic or clinical differences were noted between GBS+ and GBS-negative women. CONCLUSIONS:Nearly one in five women presenting for labor in Jordan was colonized with GBS, with serotype group III as the most common. The rapid GBS antigen diagnostic had low sensitivity and specificity. These results support expanded research in the region, including defining GBS resistance patterns, serotyping information, and risk factors. It also emphasizes the need for routine GBS testing and improved rapid GBS diagnostics for developing world settings.
PMID: 31109301
ISSN: 1471-2393
CID: 3920322
High Rate of Serotype V Streptococcus agalactiae Carriage in Pregnant Women in Botswana
A'Hearn-Thomas, Brady; Khatami, Ameneh; Randis, Tara M; Vurayai, Moses; Mokomane, Margaret; Arscott-Mills, Tonya; Banda, Francis M; Mazhani, Tiny; Lepere, Thabo; Gaolebale, Ponatshego; Nchingane, Seeletso; Chamby, Anna; Gegick, Margaret; Suzman, Evan; Steenhoff, Andrew P; Ratner, Adam J
Maternal rectovaginal colonization is the major risk factor for early-onset neonatal sepsis due to Group B Streptococcus (GBS), a major cause of early life morbidity and mortality. Transmission generally occurs perinatally from colonized mothers to infants. Vaccines targeting a subset of GBS serotypes are under development, but GBS epidemiology remains poorly understood in many African nations. We performed a cross-sectional study of GBS colonization among pregnant women at two sites in Botswana, a country with minimal prior GBS carriage data. We found a rectovaginal colonization rate of 19%, comparable with studies in other regions; however, we also noted a striking predominance of serotype V (> 45% of strains). Although further studies are required to delineate the burden of invasive GBS disease in Botswana and the generalizability of type V epidemiology, these data provide a useful baseline for understanding the potential local impact of GBS prevention strategies, including vaccines.
PMID: 30915949
ISSN: 1476-1645
CID: 3777132
Notes from the Field: Multistate Coccidioidomycosis Outbreak in U.S. Residents Returning from Community Service Trips to Baja California, Mexico - July-August 2018
Toda, Mitsuru; Gonzalez, Francisco J; Fonseca-Ford, Maureen; Franklin, Patrick; Huntington-Frazier, Melinda; Gutelius, Bruce; Kawakami, Vance; Lunquest, Kristy; McCracken, Stephanie; Moser, Kathleen; Oltean, Hanna; Ratner, Adam J; Raybern, Chelsea; Signs, Kimberly; Zaldivar, Allison; Chiller, Tom M; Jackson, Brendan R; McCotter, Orion
PMCID:6459580
PMID: 30973851
ISSN: 1545-861x
CID: 3816392
A counterselectable sucrose sensitivity marker permits efficient and flexible mutagenesis in Streptococcus agalactiae
Hooven, Thomas A; Bonakdar, Maryam; Chamby, Anna B; Ratner, Adam J
Streptococcus agalactiae (group B Streptococcus; GBS) is a cause of severe infections, particularly during the newborn period. While methods exist for generating chromosomal mutations in GBS, they are cumbersome and inefficient and present significant challenges if the goal is to study subtle mutations such as single base pair polymorphisms. To address this problem, we have developed an efficient and flexible GBS mutagenesis protocol based on sucrose counterselection against levansucrase (SacB) expressed from a temperature-selective shuttle vector. GBS containing the SacB expression cassette demonstrate lethal sensitivity to supplemental sucrose whether the plasmid DNA is replicating outside of the chromosome or has been integrated during a crossover event. Transmission electron microscopy shows that SacB-mediated lethal sucrose sensitivity results from accumulation of inclusion bodies that eventually lead to complete degradation of normal cellular architecture and subsequent lysis. We used this new mutagenesis technique to generate an in-frame, allelic exchange knockout of the GBS sortase gene srtA, demonstrating that >99% of colonies that emerge from our protocol had the expected knockout phenotype and that among a subset tested by sequencing, 100% had the correct genotype. We also generated barcoded nonsense mutations in the cylE gene in two GBS strains, showing that the approach can be used to make small, precise chromosomal mutations.Importance The ability to generate chromosomal mutations is fundamental to microbiology. Historically, however, GBS pathogenesis research has been made challenging by the relative genetic intractability of the organism. Generating a single knockout in GBS using traditional techniques can take many months, with highly variable success rates. Furthermore, traditional methods do not offer a straightforward way to generate single base pair polymorphisms or other subtle changes, especially to noncoding regions of the chromosome. We have developed a new sucrose counterselection-based method that permits rapid, efficient, and flexible GBS mutagenesis. Our technique requires no additional equipment beyond what is needed for traditional approaches. We believe that it will catalyze rapid advances in GBS genetics research by significantly easing the path to generating mutants.
PMID: 30658970
ISSN: 1098-5336
CID: 3595522
Vaginal co-colonization with multiple Group B Streptococcus serotypes
Khatami, Ameneh; Randis, Tara M; Tavares, Larissa; Gegick, Margaret; Suzman, Evan; Ratner, Adam J
Group B Streptococcus (GBS) is a neonatal pathogen frequently transmitted from maternal asymptomatic vagino-rectal colonization. Co-colonization with multiple GBS serotypes, which has implications for type-specific vaccination strategies, is difficult to detect with standard microbiologic techniques. We designed a nested real-time PCR assay to detect vaginal co-colonization in samples from a cohort of non-pregnant women (N = 433). 6/91 (6.6%) GBS-positive samples harbored ≥2 GBS serotypes, with over-representation of serotype V among co-colonized samples. Serotype IV GBS was more prevalent (>10%) in this cohort than in previously reported United States studies. Ongoing surveillance of GBS serotype epidemiology and co-colonization is indicated.
PMCID:6321774
PMID: 30528847
ISSN: 1873-2518
CID: 3579452
Storage Primes Erythrocytes for Necroptosis and Clearance
McCaig, William D; Hodges, Alexa L; Deragon, Matthew A; Haluska, Robert J; Bandyopadhyay, Sheila; Ratner, Adam J; Spitalnik, Steven L; Hod, Eldad A; LaRocca, Timothy J
BACKGROUND/AIMS/OBJECTIVE:Like nucleated cells, erythrocytes (red blood cells, RBCs) are capable of executing programmed cell death pathways. RBCs undergo necroptosis in response to CD59-specific pore-forming toxins (PFTs). The relationship between blood bank storage and RBC necroptosis was explored in this study. METHODS:Human RBCs were stored in standard blood bank additive solutions (AS-1, AS-3, or AS-5) for 1 week and hemolysis was evaluated in the context of necroptosis inhibitors and reactive oxygen species (ROS) scavengers. Activation of key factors including RIP1, RIP3, and MLKL was determined using immunoprecipitations and western blot. RBC vesiculation and formation of echinocytes was determined using phase-contrast microscopy. The effect of necroptosis and storage on RBC clearance was determined using a murine transfusion model. RESULTS:Necroptosis is associated with increased RBC clearance post-transfusion. Moreover, storage in AS-1, AS-3, or AS-5 sensitizes RBCs for necroptosis. Importantly, storage-sensitized RBCs undergo necroptosis in response to multiple PFTs, regardless of specificity for CD59. Storage-sensitized RBCs undergo necroptosis via NADPH oxidase-generated ROS. RBC storage led to RIP1 phosphorylation and necrosome formation in an NADPH oxidase-dependent manner suggesting the basis for this sensitization. In addition, storage led to increased RBC clearance post-transfusion. Clearance of these RBCs was due to Syk-dependent echinocyte formation. CONCLUSION/CONCLUSIONS:Storage-induced sensitization to RBC necroptosis and clearance is important as it may be relevant to hemolytic transfusion reactions.
PMID: 31486324
ISSN: 1421-9778
CID: 4069152
Retapamulin as a potential decolonizing agent: Activity against mupirocin-resistant strains from pediatric patients with methicillin-resistant staphylococcus aureus infection [Meeting Abstract]
Patel, A; Lighter-Fisher, J; Fulmer, Y; Copin, R; Ratner, A; Shopsin, B
Background. Controlling methicillin-resistant Staphylococcus aureus (MRSA) colonization is a common strategy to prevent transmission and recurrent infection. Standard decolonization regimens include nasal application of mupirocin ointment; however, increasing rates of mupirocin-resistance (Mup-R) have been noted globally. At our institution there has been an increase in community-acquired MRSA (CA-MRSA) infections among children living in Brooklyn, New York. A genotypic geographic cluster of an outbreak clone of the CA-MRSA strain USA 300 with a high rate (>85%) of mupirocin resistance, mediated by the plasmid borne mupA gene, was identified prompting investigation into an alternative decolonizing agent. We sought to investigate retapamulin, a topical pleuromutilin antibiotic, which has been shown to be effective against S. aureus with in vitro and in vivo activity against MRSA and a low propensity to develop resistance. Methods. Broth microdilution was used to determine the minimum inhibitory concentrations (MIC) of retapamulin against 53 Mup-R MRSA isolates collected from pediatric patients (aged 9 months-17 years) presenting to our institution over an 18 month period with clinical MRSA infection. Susceptibility defined as <=0.5 mg/L susceptible (EUCAST). Whole genome sequence data were analyzed for the presence of rplC and cfr gene mutations known to confer resistance to retapamulin. Results. All 53 isolates were susceptible to retapamulin. 49/53 (92%) strains were inhibited at MIC 0.25 mg/L, 2/53 (4%) at MIC 0.125 mg/L, and 2/53 (4%) at MIC 0.5 mg/L. DNA sequence analysis showed that one isolate had a first-step mutation in the rplC gene, but it was not associated with reduced phenotypic susceptibility to retapamulin, as the MIC of that isolate was 0.25 mg/L. Conclusion. Retapamulin demonstrated excellent in vitro activity against a genotypic cluster of Mup-R isolates from pediatric patients presenting to our institution with MRSA infection. These data suggest that retapamulin may be a promising alternative decolonization therapy for MRSA and a viable option to prevent the spread of mupirocin-resistant MRSA clones. Further research includes an ongoing randomized, placebo-controlled trial testing the in vivo efficacy of retapamulin as a nasal and perirectal decolonizing agent in children
EMBASE:629443145
ISSN: 2328-8957
CID: 4119292
Decidual stromal cell-derived PGE2 regulates macrophage responses to microbial threat
Rogers, Lisa M; Anders, Anjali P; Doster, Ryan S; Gill, Elizabeth A; Gnecco, Juan S; Holley, Jacob M; Randis, Tara M; Ratner, Adam J; Gaddy, Jennifer A; Osteen, Kevin; Aronoff, David M
PROBLEM/OBJECTIVE:Bacterial chorioamnionitis causes adverse pregnancy outcomes, yet host-microbial interactions are not well characterized within gestational membranes. The decidua, the outermost region of the membranes, is a potential point of entry for bacteria ascending from the vagina to cause chorioamnionitis. We sought to determine whether paracrine communication between decidual stromal cells and macrophages shaped immune responses to microbial sensing. METHOD OF STUDY/METHODS:production. RESULTS:in amniotic fluid, suggesting such paracrine effects might hold relevance in vivo. CONCLUSION/CONCLUSIONS:.
PMID: 30084522
ISSN: 1600-0897
CID: 3226552
Improving the Sensitivity of Real-time PCR Detection of Group B Streptococcus Using Consensus Sequence-Derived Oligonucleotides
Khatami, Ameneh; Randis, Tara M; Chamby, Anna; Hooven, Thomas A; Gegick, Margaret; Suzman, Evan; A'Hearn-Thomas, Brady; Steenhoff, Andrew P; Ratner, Adam J
Group B Streptococcus (GBS) is a perinatal pathogen and an emerging cause of disease in adults. Culture-independent GBS detection relies on polymerase chain reaction (PCR) of conserved genes, including sip. We demonstrate suboptimal sensitivity of the existing sip PCR strategy and validate an improved method based on consensus sequences from >100 GBS genomes.
PMCID:6051451
PMID: 30038931
ISSN: 2328-8957
CID: 3216032
Higher levels of a cytotoxic protein, vaginolysin, in Lactobacillus-deficient community state types at the vaginal mucosa
Nowak, Rebecca G; Randis, Tara M; Desai, Purnahamsi; He, Xin; Robinson, Courtney K; Rath, Jessica; Glover, Elbert D; Ratner, Adam J; Ravel, Jacques; Brotman, Rebecca M
Vaginolysin (VLY), a cytotoxic protein produced by Gardnerella vaginalis, may contribute to bacterial vaginosis (BV). Women with G. vaginalis, low levels of lactobacilli, history of vaginal douching, higher Nugent scores, and higher vaginal pH had increased VLY. Inflammatory markers were not highly expressed with increasing VLY. VLY's role in BV warrants further evaluation.
PMCID:5847449
PMID: 29465671
ISSN: 1537-4521
CID: 2963772