Microbiological pathogen analysis in native versus periprosthetic joint infections: a retrospective study

Background The presence or absence of an implant has a major impact on the type of joint infection therapy. Thus, the aim of this study was the examination of potential differences in the spectrum of pathogens in patients with periprosthetic joint infections (PJI) as compared to patients with native joint infections (NJI). Methods In this retrospective study, we evaluated culture-positive synovial fluid samples of 192 consecutive patients obtained from January 2018 to January 2020 in a tertiary care university hospital. For metrically distributed parameters, Mann–Whitney U was used for comparison between groups. In case of nominal data, crosstabs and Chi-squared tests were implemented. Results Overall, 132 patients suffered from periprosthetic joint infections and 60 patients had infections of native joints. The most commonly isolated bacteria were coagulase-negative Staphylococci (CNS, 28%), followed by Staphylococcus aureus (S. aureus, 26.7%), and other bacteria, such as Streptococci (26.3%). We observed a significant dependence between the types of bacteria and the presence of a joint replacement (p < 0.05). Accordingly, detections of CNS occurred 2.5-fold more frequently in prosthetic as compared to native joint infections (33.9% vs. 13.4% p < 0.05). In contrast, S. aureus was observed 3.2-fold more often in NJIs as compared to PJIs (52.2% vs. 16.4%, p < 0.05). Conclusion The pathogen spectra of periprosthetic and native joint infections differ considerably. However, CNS and S. aureus are the predominant microorganisms in both, PJIs and NJIs, which may guide antimicrobial therapy until microbiologic specification of the causative pathogen.

Isolation and antimicrobial resistance of coagulase-negative staphylococci recovered from healthy tortoises in Minas Gerais, Brazil

ABSTRACT: In the last few decades, there has been a global increase in the adoption of reptiles as companion animals, mainly turtles and tortoises. Considering the popularity of reptiles as pets in Brazil, and a notable lack of data about potentially pathogenic staphylococci in these animals, this study isolated and evaluate the antimicrobial susceptibility of staphylococcal species from healthy tortoises (Chelonoidis carbonaria) in Brazil. During a 12-month period (February 2019 to February 2020), cloacal swabs from 66 healthy tortoises were collected at the Wild Animals Screening Center in Belo Horizonte, Minas Gerais, Brazil. The swabs were plated onto mannitol salt agar for staphylococci isolation, and species identification was performed using MALDI-TOF MS. Antimicrobial susceptibility was investigated using the disk diffusion method, and the presence of the mecA gene was investigated by PCR to detect methicillin resistance. Of the tested animals, 72.7% were positive for staphylococcal isolation. All isolates were coagulase-negative staphylococci (CoNS), and Staphylococcus sciuri (81.3%), and S. xylosus (12.5%) were the most frequently isolated species. The majority of the isolates (56%) were resistant to at least one antimicrobial agent. A high frequency of resistance was observed for penicillin (35.5%) and tetracycline (29.1 %). All strains were susceptible to cefoxitin, chloramphenicol, ciprofloxacin, erythromycin, and gentamicin. All isolates were negative for the mecA gene. The present work suggests that healthy tortoises are mainly colonized by CoNS, especially S. sciuri. Half of the isolates were resistant to at least one antimicrobial, raising questions regarding the possible role of these animals as reservoirs of antimicrobial resistance genes.

The Species Composition of Microbiota and Biological Properties of Dominant Bacterial Species in the Lacrimal Fluid in Patients with Endogenous Uveites

The purpose: to study the species composition of the lacrimal fluid microbiota in patients with endogenous uveitis and the biological properties of dominant species of bacteria.Patients and Methods. A bacteriological study of the lacrimal fluid of 107 patients (114 eyes) with endogenous uveitis and 28 practically healthy persons (control) was carried out. The research was performed using the conventional methods. The isolated microorganisms were identified up to the species. We studied the main biological properties of bacteria — the presence of persistence and virulence factors of isolated dominant species.The results. 43 strains of various types of bacteria were isolated from the lacrimal fluid of patients with uveitis, bacteria of the genus Staphylococcus prevailed, S. aureus was isolated in 23.3 % of cases, and the remaining strains were representatives of coagulase-negative staphylococci. The species composition of the bacteria isolated from practically healthy individuals did not differ in essence. Isolated strains of S. aureus had a significant set of virulence factors. All isolates lysed sheep red blood cells, 80 % of the cultures had lecithovitellase and 60 % — DNA-se activity. Representatives of coagulase-negative staphylococci were characterized only by hemolytic activity. In the study of persistence factors, it was found that all the studied strains of S. aureus and the vast majority of representatives of coagulase-negative staphylococci isolated from tears were resistant to lysozyme. Biofilm formation was more typical for S. aureus strains 90 % versus 34.4 % for representatives of coagulase-negative staphylococci (t = 2.194, p = 0.034). Similar patterns were found in relation to complement resistance, 90 % of S. aureus cultures and 37.5 % of coagulase-negative staphylococci (t = 2.055; p = 0.046).Conclusion. Among the microorganisms isolated from the lacrimal fluid, Staphylococcus bacteria prevailed, from which S. cohnii was most often isolated. S. aureus to a greater extent than coagulase-negative staphylococci had a certain set of virulence and persistence factors. The microbiocenosis of the lacrimal fluid of patients with endogenous uveitis did not differ from practically healthy individuals. The presence of S. aureus in lacrimal fluid is a risk factor for the development of endogenous uveitis in cases of chronic oral and ENT organ diseases.

Antimicrobial Resistance of Staphylococcus sp. Isolated from Cheeses

S. aureus and some species of coagulase-negative staphylococci, including S. chromogenes and S. simulans, commonly cause intramammary infections. However, little attention was paid to the antimicrobial resistance of these species with respect to their occurrence in dairy products, for example, popular sheep and goat cheeses made from unpasteurized milk. The aim of this study was to investigate such sheep and goat cheeses for the occurrence and antimicrobial resistance of the relevant staphylococci species. The staphylococcal isolates were identified by polymerase chain reaction (130 isolates) and matrix assisted laser desorption/ionization time-of-flight mass spectrometry. The most common species of S. aureus (56 isolates) were identified, as well as S. chromogenes (16 isolates) and S. simulans (10 isolates). Antimicrobial resistance to penicillin, oxacilin, ceftaroline, teicoplanin, gentamicin, erythromycin, tetracycline and ofloxacin was subsequently determined in these species using the agar dilution method. The highest resistance was confirmed in all species, especially to penicillin (91%) and erythromycin (67%). The highest sensitivity was confirmed to ofloxacin (83%). Due to the high incidence of penicillin and oxacilin-resistant staphylococci, the mecA gene was detected by polymerase chain reaction, which was confirmed only in S. aureus isolates (19%). Our study shows that the tested strains (77%) were resistant to more than one antibiotic at a time.

Clinical characteristics and outcome of neonates with neonatal mastitis: a hospital based study

Background: Neonatal mastitis is not an uncommon condition, mostly occurs due to Staphylococcus aureus (S. aureus), sometimes leading to breast abscess with detrimental effects.Methods: Our study was retrospective, hospital based observational study carried out at Government Medical College, Baramulla from August 2017 to August 2019, all cases with features of neonatal mastitis were included in the study and also admitted in hospital. Clinical and laboratory data along with demographic data was recorded and analysed.Results: 23 cases were included with age of presentation 8 to 28 days. Babies particularly male babies received breast massage (N=10), besides this pain (15) and redness (N=23) was most common clinical characteristics purulent discharge seen in 2 cases and 7 cases were febrile. Laboratory findings include decreased total leucocyte count (TLC) and positive C-reactive protein (CRP), pus culture from samples revealed S. aureus in 11 cases, coagulase-negative staphylococci (CONS) in 3 cases, E. coli in 2 cases and sterile in 7 cases. Most of cases were sensitive to penicillin (N=14) and in two cases were methicillin resistant S. aureus (MRSA) strains resistant to methicillin. All patients responded well to intravenous (IV) antibiotics while as 8 cases required (I and D), blood cultured showed growth in 19 cases while cerebrospinal fluid (CSF) analysis was sterile in all patients. Above all babies were discharged successfully without any complications.Conclusions: We concluded from our study that neonatal mastitis if treated early has better outcome rather than practicing misbeliefs like breast massage to express so called witch’s milk, in addition we conclude that neonatal mastitis is not an uncommon problem.

Microbiological Profile of Neonatal Septicemia by Automated Blood Culture System (BacT/ALERT) at a Tertiary Care Hospital in Jamnagar, Gujarat, India

Background: This study was carried out to do rapid diagnosis of neonatal septicemia to prevent septicemia related complications and neonatal morbidity and mortality. Materials and Methods: This study was carried out in a tertiary care hospital from a period of March 2014 to August 2015. This is a non-randomized, prospective study in which one hundred and nine cases of suspected neonatal septicemia on the basis of antenatal high risk factors and signs and symptoms of sepsis were studied. Blood samples were collected from neonates in whom septicemia was suspected usually before antibacterial agents were given and both positive and negative samples were detected by automated system BacT/ALERT. Results: Out of 109 samples tested, 69 samples were positive and 40 samples were negative. The incidence of neonatal septicemia due to Gram positive organisms (62.85%) was found to be high. Among them Coagulase negative staphylococci (CONS) (27) (38.57%) was most common organism followed by Staphylococcus aureus (11) (15.71%), Enterococcus spp. (7.14%) and Streptococcus spp. (1.43%). Rate of Gram negative organisms was quite low (32.85%). Out of them Acinetobacter spp. (17.14%) was most common followed by Klebsiella spp. (7.14%), E.coli (5.71%) and Pseudomonas spp. (2.86%). Conclusion: Early detection of infection in neonates and proper antibiotics for the treatment leads to reduced morbidity and mortality.

ROLE OF ANTIBIOTIC PROPHYLAXIS ON SURGICAL SITE INFECTION IN ELECTIVE ABDOMINAL SURGER

Surgical site infection (SSI) are healthcare-associated infections(HAIs) with signicant source of preventable morbidity and mortality. Prophylactic antibiotics are used most often to prevent infection of a surgical incision. S. aureus, coagulase-negative Staphylococci and Enterococci are the three organisms most commonly isolated from SSI

Antimicrobial Activity of Fuller’s Earth, Turmeric, and Sandalwood against Streptococcus Mutans, Micrococci and Coagulase Negative Staphylococci -an In vitro Study

Introduction: Sandalwood powder (Santalum alba) is used if the skin is oily for removing dark spots on the skin. Sandalwood has an anti-tanning and anti-aging property. Turmeric powder (Curcuma longa) is mainly used to rejuvenate the skin. It helps to delay aging like wrinkles and also possesses other properties like antibacterial, antiseptic, and anti-inflammatory, and many other properties. Multani mitti helps the skin in many different ways like the reduction of pore size pore sizes, removing blackheads and removing whiteheads fading freckles, soothing sunburns, cleansing skin, improving blood circulation, complexion, reducing acne and blemishes, and gives a glowing effect to your skin as they contain many-particles which can inhibit various organisms. Materials and Methods: In this investigation, the antimicrobial viability of Turmeric, sandalwood and Multani Mutti was tested against Streptococcus mutans, Micrococci, and coagulase-negative staphylococcus. The microorganisms were filled in strong media, and culture containing stock suspensions was made and, in this way, standard strains of Streptococcus mutans, Micrococci, and Coagulase-negative staphylococci were obtained. Microorganisms were subcultured in fitting society media to affirm their virtue. Results: The zone of inhibition of turmeric against Streptococcus mutans is about 11mm. The zone of inhibition of turmeric against Micrococci is about 9 mm. The zone of inhibition of turmeric against Coagulase-negative staphylococci is about 13mm. There was no zone of inhibition for both sandalwood and Multani mitti for Coagulase-negative staphylococci, Streptococcus mutans, and Micrococci. Conclusion: The study proves the turmeric has antimicrobial potential against Coagulase-negative staphylococci, Streptococcus mutans,, and Micrococci with good prospects of development into antimicrobial face pack or face wash

Microbial Analysis of Contact Lenses

Introduction: Contact lenses are small, thin lenses which are worn directly on the surface of the eyes. They can be worn aesthetically or to correct vision. Contact lens related eye infections can lead to serious complications such as blindness, and are associated with several risk factors such as sleeping with lenses, exposure to water, not adhering to replacement schedules, and reusing disinfecting solutions, among others. The severity of the infection may vary with the degree of pathogenicity of the microorganism. Hygiene and handling of contact lenses play a very important role. The main aim of this study is to assess the microbial analysis of contact lenses. Materials and Methods: A total of 15 lenses were collected in 2 ml sterile saline solution individually and manually agitated for five minutes. The lens was then removed using a sterile toothpick from the container. The sterile container was stored at 4°C till it was processed. 50 microliter of the sample was transferred using a pipette and inoculated on nutrient agar, blood agar and sabouraud dextrose agar. The microorganism (fungus or bacteria) were identified by standard protocol. Results and Discussion: Bacillus, Staphylococcus aureus and CONS [Coagulase Negative Staphylococci] were found in blood agar. No fungal growth was found among the samples. More importance could be given to contact lenses handling and hygiene to avoid eye related bacterial and fungal infections. Conclusion: In the present study, the total CFU (Colony Forming Unit) was found to be confluent in all the participants who wore contact lenses for 4 months compared to those who have worn contact lenses from 15 and 28 days. Only bacterial growth was seen in the culture plate. There was no fungal growth seen from the samples collected.