BackgroundCarbapenem-resistant Enterobacteriaceae (CRE) infections have emerged as a serious threat to health worldwide. They are associated with increased morbidity and mortality and are capable of silently colonizing the gastrointestinal tract. Because of this, there is great interest to characterize the epidemiology of CRE carriage and acquisition in healthcare facilities. The aim of this study was to determine the prevalence and factors associated with CRE fecal carriage (CRE-fc), and risk factors for incident cases.Methods/ResultsA cohort study was conducted at a tertiary care hospital from January 1st to April 30th, 2014 during a CRE outbreak. Weekly rectal swabs were performed in patients considered at risk until discharge. CRE-fc prevalence was 10.9% (CI 95% 7.7–14.7) among 330 patients. Treatment with carbapenems (OR 2.54, CI 95% 1.15–5.62); transfer from an institution (OR 2.16, CI 95% 1.02–4.59); multi-drug resistant infection within the previous six months (OR 2.81, CI 95% 1.47–5.36); intensive care unit admission (OR 0.42, CI 95% 0.20–0.88); hematologic malignancy (OR 4.02, CI 95% 1.88–8.06); invasive procedures (OR 2.18, CI 95% 1.10–4.32); and sharing a room with a known CRE carrier (OR 3.0, CI 95% 1.43–6.31) were independently associated factors for CRE-fc. Risk factors associated with CRE-fc incidence were determined for 87 patients initially negative and with subsequent screening; the incidence rate was 2.5 cases, per 1000 person-years (CI 95% 1.5–3.9). Independently associated risk factors were carbapenem treatment (HR 2.68, CI 95% 1.03–6.98), hematologic malignancy (HR 5.74, 95% CI 2.46–13.4) and a mean daily colonization pressure ≥10% (HR 5.03, IC 95% 1.77–14.28). OXA-48-like (OXA-232) and CTX-M-15 were the predominantly identified mechanisms of resistance.ConclusionsWe found an elevated incidence and prevalence of CRE-fc in our hospital. Hematologic patients need to be considered a population at risk, and antibiotic stewardship along with infection control programs need to be improved to avoid nosocomial spread.

Objectives Investigate the feasibility of saliva sampling as a noninvasive and safer tool to detect SARS-CoV-2 and to compare its reproducibility and sensitivity with nasopharyngeal swab samples (NPS). The use of sample pools was also investigated. Methods 2107 paired samples were collected from asymptomatic health care and office workers in Mexico City. Sixty of these samples were also analyzed in two other independent laboratories for concordance analysis. Sample processing and analysis of virus genetic material were performed according to standard protocols described elsewhere. Pooling analysis was performed by analyzing the saliva pool and the individual pool components. Results The concordance between NPS and saliva results was 95.2% (Kappa: 0.727, p = 0.0001) and 97.9% without considering inconclusive results (Kappa: 0.852, p = 0.0001). Saliva had a lower number of inconclusive results than NPS (0.9% vs 1.9%). Furthermore, saliva shows a significantly higher concentration of both total RNA and viral copies than NPS. Comparison of our results with those of the other two laboratories shows 100% and 97% concordance. Saliva samples are stable without the use of any preservative, a positive SARS-CoV-2 sample can be detected 5, 10, and 15 days after collection when the sample is stored at 4 °C. Conclusions Our results indicate that saliva is as effective as NPS for the identification of SARS-CoV-2-infected asymptomatic patients, sample pooling facilitates the analysis of a larger number of samples with the benefit of cost reduction.

Carbapenem-resistant Enterobacteriaceae carrying New Delhi metallo-␤-lactamase 1 (NDM-1) have rarely been reported in Latin America. We report of an outbreak caused by a bla NDM-1 -harboring plasmid spread through different bacterial species, including Escherichia coli (ST617) and Enterobacter cloacae (ST182) isolates from the same patient and three Klebsiella pneumoniae isolates (ST22) derived from three epidemiologically related patients. IncFII plasmids were found in all strains. Measures to control the outbreak were applied successfully. The spread of carbapenem-resistant Enterobacteriaceae (CRE) is a global concern. The most common mechanism of CRE is the acquisition of plasmid-borne ␤-lactamases that can hydrolyze carbapenems. The New Delhi metallo-␤-lactamase (MBL) 1 (NDM-1) has been reported in several regions of the world, mostly in patients with a history of travel to areas where it is endemic but scarcely in Latin America (1-4). We report an outbreak caused by NDM-1-harboring Enterobacteriaceae, where horizontal gene transfer likely occurred between different species with further clonal expansion.Hospital setting and bacterial strains. Ours is a 230-bed tertiary care hospital in Mexico City with a 14-bed intensive care unit (ICU) to which adult patients from the all of Mexico are referred for medical treatment. The first case of CRE carrying an MBL was detected on 5 November 2013 in a patient transferred from a southwestern city in Mexico who was admitted to the ICU. A second case was identified on 14 December 2013 in the ICU. After this, we established active screening of CRE carriers via rectal swab cultures. Rectal swabs were cultured using a 10-g ertapenem disk in 5 ml Trypticase soy broth (6). Other clinical samples were collected from the patients according to the usual protocol.Antimicrobial susceptibility tests and molecular detection of ␤-lactamases. Identification and antimicrobial susceptibility of the isolates were done with the Vitek 2 (bioMérieux, Durham, NC) and interpreted according to CLSI standards (7). Additionally, the EDTA double-disc synergy phenotypic test was performed to detect metallo-␤-lactamases (8). Presence of ␤-lactamases was determined by PCR (bla IMI , bla VIM , bla NDM , bla GES bla CTX-M-15 , bla , bla SHV , bla TEM ), as described elsewhere (8, 9). PCR-generated fragments were purified by Qiaquick PCR purification spin columns (Qiagen, Venlo, Netherlands), and sequenced with a 3130xl genetic analyzer (AB Applied Biosystems, Hitachi, San Francisco, CA). The nucleotide sequences were analyzed through the National Center for Biotechnology Information website (http://www.ncbi.nlm.nih.gov). Five isolates (1 Escherichia coli, 1 Enterobacter cloacae, and 3 Klebsiella pneumoniae) from four patients were evaluated. All isolates showing resistance to third-generation cephalosporins, quinolones, monobactams, carbapenems, and PCR were positive for NDM-1 and CTX-M-15 (Table 1).Genotyping. Pulsed-field gel electrophoresis (PFGE) was performed for all K. pneumoniae clinical (n ϭ ...

Background The progressive disseminated histoplasmosis (PDH) has been associated with severe disease and high risk of death among people living with HIV (PLWHIV). Therefore, the purpose of this multicenter, prospective, double-blinded study done in ten Mexican hospitals was to determine the diagnostic accuracy of detecting Histoplasma capsulatum antigen in urine using the IMMY ALPHA Histoplasma EIA kit (IAHE), clarus Histoplasma GM Enzyme Immunoassay (cHGEI IMMY) and MiraVista Histoplasma Urine Antigen LFA (MVHUALFA); as well as the Hcp100 and 1281-1283220SCAR nested PCRs in blood, bone-marrow, tissue biopsies and urine. Methodology/Principal findings We included 415 PLWHIV older than 18 years of age with suspicion of PDH. Using as diagnostic standard recovery of H. capsulatum in blood, bone marrow or tissue cultures, or histopathological exam compatible, detected 108 patients (26%, [95%CI, 21.78–30.22]) with proven-PDH. We analyzed 391 urine samples by the IAHE, cHGEI IMMY and MVHUALFA; the sensitivity/specificity values obtained were 67.3% (95% CI, 57.4–76.2) / 96.2% (95% CI, 93.2–98.0) for IAHE, 91.3% (95% CI, 84.2–96.0) / 90.9% (95% CI, 87.0–94.0) for cHGEI IMMY and 90.4% (95% CI, 83.0–95.3) / 92.3% (95% CI, 88.6–95.1) for MVHUALFA. The Hcp100 nested PCR was performed on 393, 343, 75 and 297, blood, bone marrow, tissue and urine samples respectively; the sensitivity/specificity values obtained were 62.9% (95%CI, 53.3–72.5)/ 89.5% (95%CI, 86.0–93.0), 65.9% (95%CI, 56.0–75.8)/ 89.0% (95%CI, 85.2–92.9), 62.1% (95%CI, 44.4–79.7)/ 82.6% (95%CI, 71.7–93.6) and 34.9% (95%CI, 24.8–46.2)/ 67.3% (95%CI, 60.6–73.5) respectively; and 1281-1283220SCAR nested PCR was performed on 392, 344, 75 and 291, respectively; the sensitivity/specificity values obtained were 65.3% (95% CI, 55.9–74.7)/ 58.8% (95%CI, 53.2–64.5), 70.8% (95%CI, 61.3–80.2)/ 52.9% (95%CI, 46.8–59.1), 71.4% (95%CI, 54.7–88.2)/ 40.4% (95%CI, 26.4–54.5) and 18.1% (95%CI, 10.5–28.1)/ 90.4% (95%CI, 85.5–94.0), respectively. Conclusions/Significance The cHGEI IMMY and MVHUALFA tests showed excellent performance for the diagnosis of PDH in PLWHIV. The integration of these tests in clinical laboratories will certainly impact on early diagnosis and treatment.

BackgroundThe Histoplasma urine antigen (HUAg) is the preferred method to diagnose progressive disseminated histoplasmosis (PDH) in HIV patients. In 2007, IMMY ALPHA Histoplasma EIA was approved for clinical for on-site use, and therefore useful for regions outside the United States. However, ALPHA-HUAg is considered inferior to the MVista-HUAg which is only available on referral. We aim to evaluate the diagnostic accuracy of ALPHA-HUAg.Methodology/Principal findingsWe conducted a multicenter, prospective, diagnostic test study in two secondary and eight tertiary-care facilities in Mexico. We included HIV patient with PDH suspicion and evaluated ALPHA-HUAg diagnostic accuracy using as reference standard the Histoplasma capsulatum growth on blood, bone marrow, and tissue cultures or compatible histopathologic exam (PDH–proven). We evaluated the results of 288 patients, 29.5% (85/288; 95% confidence interval [CI], 24.3–35.1) had PDH. The sensitivity of ALPHA-HUAg was 67.1% (95% CI, 56–76.8%) and the specificity was 97.5% (95% CI, 94.3%-99.1%). The positive likelihood ratio was 27.2 (95% CI; 11.6–74.4). In 10.5% of the PDH–proven patients, a co-existing opportunistic infection was diagnosed, mostly disseminated Mycobacterium avium complex infection.Conclusions/SignificanceWe observed a high specificity but low sensitivity of IMMY-HUAg. The test may be useful to start early antifungals, but a culture-based approach is necessary since co-infections are frequent and a negative IMMY-HUAg result does not rule out PDH.