Kytococcus schroeteri: An Emerging Pathogen on the Horizon

Kytococcus has long been considered to be a skin commensal or environmental contaminant. However, it has emerged as an aetiological agent of prosthetic valve infective endocarditis, pneumonia, bacteremia, osteoarticular, and implant/device infections, especially in patients with immunocompromised conditions, such as haematological malignancies, febrile neutropaenia and in patients on immunosuppressant therapy. We report a case of prosthetic valve endocarditis associated with Kytococcus schroeteri in a patient with rheumatic heart disease and mitral valve replacement. Special efforts to reach correct identification have to be made as Kytococcusis, commonly resistant to penicillins and oxacillins; and often needs prolonged treatment with glycopeptides containing combination antimicrobial therapy.

Investigation of rodent reservoirs of emerging pathogens in Côte d'Ivoire, West Africa

Background: One of the main health problems in West Africa remains upsurge of emerging pathogens. Ebola virus disease outbreak occurred in 2014 in Liberia, Guinea and Sierra Leone, Monkeypox virus in Nigeria in 2017 and most recently Lassa virus in Nigeria, Togo and Benin in 2018. These pathogens have animal reservoirs as vectors for transmission. Proper investigation of the pathogens in their rodent vectors could help reduce and manage their emergence and spread. Methodology: This study was conducted with an approval from the Côte d'Ivoire Bioethics Community. Small mammal trappings were carried out in 9 sites within three zones namely, peri-urban, peri-rural and protected areas. Liver, lung and kidney tissues from trapped small mammals were sampled in accordance with the recommended conditions of biosafety and bioethics. The organs were transported in liquid nitrogen to the laboratory. Molecular tests were used to detect pathogens. Orthopoxviruses and Monkeypox virus were detected in the organs by PCR using consensus primers targeting the virus surface membrane haemagglutinin (HA) genes, while Leptospira species were detected by PCR using primers targeting the rrs and lfb1 genes. Results: Out of 4930 night-traps, 256 (5.19%) small mammals were trapped including Crocidura, Rattus, Lophuromys, Praomys, Mus and Mastomys. Leptospira species were detected in 6 genera from 7 study sites and the infected small mammals accounted for 13.3%. Leptospira sp was detected mainly in the rodent vector genera Rattus (32.3%), Lophuromys (29.0%), and Praomys (16.1%). Three species of Leptospira were detected and Leptospira interrogans was the most common frequent species (74.2%). Monkeypox virus was not detected from studied small mammals. Conclusion: The initial data from our investigation indicates the presence of Leptospira sp in rodent vectors, Rattus, Lophuromys and Praomys, which are the potential small mammalian reservoirs of this pathogen in Cote d'Ivoire.

Candida auris: a bibliometric analysis of the first ten years of research (2009-2018)

Candida auris (C. auris) is an emerging multidrug resistant fungus considered as the cause of several nosocomialinfections of bad prognosis. This study presents a bibliometric analysis of global scientific research on C. auris sinceit was isolated first in 2009. A systematic search was conducted in Scopus databases in the period of 2009–2018 and atotal of 227 indexed documents were retrieved. A sharp increase in the number of studies related to drug and multidrugresistance of C. auris during 2016–2018 was observed, coinciding with an increase in the number of first-case andoutbreak reports worldwide. The leading countries based on the number of publications were United States, India,and the United Kingdom. Nevertheless, Netherlands ranked first when (i) ratio between the number of citations andnumber of publications, (ii) ratio between the number of publications and gross domestic product (GDP), and (iii) ratiobetween the number of citations and GDP were used as indicators of productivity. Despite the recent emergence of thetopic since the first-case report in 2009, recent research efforts have allowed identifying Ibrexafungerp (SCY-078) andRezafungin (CD101) as possible candidates for facing the actual antifungal resistance of C. auris.

Citrobacter spp. Isolated from Pus Samples in a Tertiary Care Hospital and its Antibiogram in Sonepat, Haryana, India

Introduction: Citrobacter infection occurs in a hospital setting in patients with multiple comorbidities and it occasionally causes disease in general population. Neonates and immunocompromised are highly susceptible to Citrobacter infections which are mainly caused by Citrobacter freundii and Citrobacter koseri, the incidence of nosocomial infections caused by antibioticresistant Gram-negative pathogens is increasing. This study was done to know the development of drug resistance in emerging pathogen Citrobacter. Methods: The study was conducted in the department of microbiology in a tertiary care hospital for a period of 1 year. Bacterial identification was performed by routine conventional microbial culture and biochemical tests using standard recommended techniques. The antimicrobial susceptibility testing was performed by the Kirby–Bauer disk diffusion technique on Mueller‑Hinton agar, as per the Clinical and Laboratory Standards Institute guidelines. Results: In the present study, 1788 pus samples were processed for a period of 1 year, out of which in 808 pus samples, organisms were isolated. Staphylococcus aureus was isolated in 234 (28.96%) cases. Escherichia coli was isolated in 168 (20.79%) cases, Pseudomonas was isolated in 125 (15.47%) cases, and Proteus was isolated in 32 (3.96%) cases. Enterobacter spp. was isolated in 51 (6.31%) cases. Acinetobacter was isolated in 16 (1.98%) cases. Candida spp. was 17 (2.10%). Citrobacter spp. was isolated in 85 (10.52%) cases. In 85 cases of Citrobacter spp., 58 (68.23%) were C. freundii and 27 (31.76%) were C. koseri. In the present study, Citrobacter spp. was sensitive to amikacin in 36.47% of cases, gentamycin in 48.88% of cases, and levofloxacin in 29.41% of cases. Conclusion: Citrobacter species is an emerging pathogen developing drug resistance. Drug options are limited in the current scenario; hence, injudicious and inadequate use of antibiotics should be avoided.

Microbiological Characteristics of Corynebacterium striatum, an Emerging Pathogen / 한양의대학술지

C. striatum is part of the normal skin and mucous membrane flora in humans and is widely disseminated in the environment. Traditionally, these strains have been considered contaminants. However, C. striatum has been linked to respiratory infection, bacteremia, and endocarditis; and it is strongly related to nosocomial outbreaks. At present, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) is the most accurate routine identification method. Many C. striatum strains are multi-drug resistant, being susceptible only to vancomycin and linezolid. We should survey the antimicrobial susceptibility results regularly to monitor its resistance and consider it a possible pathogen.

Recent research advances on Chromobacterium violaceum

Chromobacterium violaceum is a gram-negative bacterium, which has been used widely in microbiology labs involved in quorum sensing (QS) research. Among the QS-regulated traits of this bacterium, violacein production has received the maximum attention. Violacein production in this organism, however is not under sole control of QS machinery, and other QS-regulated traits of this bacterium also need to be investigated in better detail. Though not often involved in human infections, this bacterium is being viewed as an emerging pathogen. This review attempts to highlight the recent research advances on C. violaceum, with respect to violacein biosynthesis, development of various applications of this bacterium and its bioactive metabolite violacein, and its pathogenicity.

Recent research advances on Chromobacterium violaceum

Chromobacterium violaceum is a gram-negative bacterium, which has been used widely in microbiology labs involved in quorum sensing (QS) research. Among the QS-regulated traits of this bacterium, violacein production has received the maximum attention. Violacein production in this organism, however is not under sole control of QS machinery, and other QS-regulated traits of this bacterium also need to be investigated in better detail. Though not often involved in human infections, this bacterium is being viewed as an emerging pathogen. This review attempts to highlight the recent research advances on C. violaceum, with respect to violacein biosynthesis, development of various applications of this bacterium and its bioactive metabolite violacein, and its pathogenicity.

Virulence Markers and Antifungal Susceptibility Profile of Candida glabrata: An Emerging Pathogen.

Aims: To study virulence factors and antifungal susceptibility profile of C. glabrata isolated from various clinical specimens. Study Design: A total of 175 C. glabrata spp. isolated from various clinical specimens were included in the study. Place and Duration of Study: Department of Microbiology, Rural Medical College, Pravara Institute of Medical Sciences (PIMS), Loni, Maharashtra, India, between March 2008 to March 2013. Methodology: C. glabrata was identified by sugar assimilation and fermentation tests and colony color on Hichrome Candida agar. HiCandida identification kit supplemented the identification of the isolates. The virulence markers studied were production of extracellular hydrolytic enzymes (phospholipase, proteinase and coagulase), haemolytic activity and biofilm formation. The antifungal susceptibility profile of C. glabrata isolates was determined by Hicomb minimum inhibitory concentration (MIC) test. The antifungal agents used were amphotericin B (range 0.002-32 μg), fluconazole (range 0.016-256 μg), itraconazole (range 0.002-32 μg) and ketoconazole (range 0.002-32 μg). Results: Maximum number of isolates were obtained from blood culture (36%) followed by urine sample (29.7%). ICU stay followed by HIV infection were the main predisposing factors found to be associated with C. glabrata infection. A total of 53 (30.2%) C. glabrata isolates showed phospholipase activity. Proteinase production was seen in 56 (32%) isolates. 48 (27.4%) isolates were coagulase positive. Haemolytic activity was noted in 43 (24.5%) isolates. Most of C. glabrata produced β- type of haemolysis on sheep blood SDA agar. Biofilm forming ability was noted in 68 (38.8%) isolates. Maximum isolates were resistant to fluconazole (46.8%) and ketoconazole (46.8%) followed by itraconazole (45.7%). Amphotericin B resistance was seen in 58 (33.1%) isolates. Conclusion: Once considered as a non pathogenic human commensal, C. glabrata has emerged as an important pathogen in various clinical types of candidiasis. C. glabrata is innately resistant to antifungal drugs and various antifungal mechanisms of the body. Present research data available is not satisfactory to understand the pathogenic and other mechanisms involved in the transition of C. glabrata from nonpathogenic commensal to a potential pathogen. Therefore more research studies are needed to explain pathogenesis, host-pathogen interaction and other survival properties of this emerging pathogen.

Pneumococcusuria: From bench to bedside.

The present study highlights six cases of pneumococcusuria during the time period of May 2008 to May 2010. All the patients had a co-existing predisposing factor with the isolation of Streptococcus pneumoniae in urine. Five of the six patients having signs and symptoms of urinary tract infections (UTI) were treated and cured of the same. It becomes essential to consider pneumococcal UTI in the presence of clinical signs and symptoms associated with urinary tract abnormalities like hydronephrosis and renal stones. S. pneumoniae may be regarded as an emerging pathogen in UTI. Precise microbiological diagnosis must correlate with the clinical signs and symptoms for the administration of appropriate antibiotic therapy.

Prosthetic aortic valve endocarditis due to Ochrobactrum anthropi.

Ochrobactrum anthropi is an emerging pathogen increasingly affecting the immunocompromised host. Only four cases of infective endocarditis have been documented in literature. Therapeutic approach is a rising challenge as it is resistant to most of the currently available beta lactam antibiotics with the exception of carbapenems. We report a case of prosthetic valve endocarditis secondary to Ochrobactrum anthropi infection; the host was temporarily immunocompromised due to disseminated herpes zoster after surgery.