Extensive perineal ecthyma gangrenosum in leukocyte adhesion deficiency type 1 associated with Staphylococcus hominis bacteremia.

Leukocyte adhesion deficiency (LAD), a disorder of neutrophil function, is characterized by a defect in leukocyte adhesion to the endothelium. Recurrent infections in the skin, soft tissue, gingiva, and lungs due to Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella sp. are common in these patients. Ecthyma gangrenosum (EG) is an ulcer of skin and subcutaneous tissue with a black eschar and surrounding erythematous halo secondary to a bacterial infection. Here, we report an unusual presentation of LAD type-1 with extensive EG of perineum secondary to Staphylococcus hominis bacteremia treated successfully with combination of granulocyte transfusion and diversion colostomy.

Detection of sasX Gene and Distribution of SCCmec Types in Invasive and Non-invasive Coagulase-negative Staphylococci

Background: Coagulase-negative staphylococci, which belong to the normal microbiota of the skin and mucous membranes, are opportunistic pathogens. sasX, a newly described protein, is thought to play an important role in nasal colonization and methicillin-resistant Staphylococcus aureus virulence, and it may be acquired from coagulase-negative staphylococci by horizontal gene transfer. It has been considered that understanding the function of sasX gene may help clarify the relevance of the different adhesion mechanisms in the pathogenesis of infections associated with biofilm. Aims: To investigate the sasX gene presence, staphylococcal cassette chromosome mec types, and antimicrobial resistance patterns of invasive and noninvasive coagulase-negative staphylococci isolates. Study Design: Cross-sectional study. Methods: The study included a total of 180 coagulase-negative staphylococci strains. Non-invasive isolates (n=91) were obtained from the hands of healthy volunteers who do not work at the hospital (n=30), the nasal vestibule of healthy volunteer hospital workers (n=26), and central venous catheter (n=35). Invasive isolates (n=89) were isolated from peripheral blood cultures of inpatients who do not have catheters. All isolates were identified by conventional microbiological methods, automated systems, and, if needed, with matrix-assisted laser desorption/ionization-time of flight. Staphylococcal cassette chromosome mec typing, sasX and mec gene detection, antibiotic susceptibility, and sasX gene sequence analysis were performed. Results: Peripheral blood, central venous catheter colonization, and nasal vestibule isolates were positive for the sasX gene, whereas hand isolates were negative. sasX gene was present in 17 isolates, and no statistical significance was found between invasive and noninvasive isolates (p=0.173). Sequence analysis of the sasX genes showed high homology to related proteins of Staphylococcus phage SPbeta-like and Staphylococcus epidermidis RP62A. staphylococcal cassette chromosome mec type V was the most prevalent regardless of species. staphylococcal cassette chromosome mec type II was more frequent in invasive isolates and found to be statistically important for invasive and noninvasive S. epidermidis isolates (p=0.029). Staphylococcus haemolyticus isolates had the overall highest resistance rates. Resistance to ciprofloxacin, trimethoprim-sulfamethoxazole, and erythromycin was found to be higher in isolates from catheter and blood culture. Staphylococcus hominis isolates had the highest rate for inducible clindamycin resistance. None of the isolates were resistant to vancomycin, teicoplanin, and linezolid. Conclusion: The sasX gene is detected in 9.44% of the isolates. There is no statistical difference between the sasX-positive and -negative isolates in terms of antibacterial resistance and the presence of sasX and SCCmec types. Further studies about the role of sasX at virulence in coagulase-negative staphylococci, especially from clinical samples such as tracheal aspirate and abscess isolates, and distribution of staphylococcal cassette chromosome mec types are needed.

Distinguishing coagulase-negative Staphylococcus bacteremia from contamination using blood-culture positive bottle detection pattern and time to positivity.

AIM: Detection of coagulase-negative Staphylococcus in blood culture may be a result of either bacteremia or contamination. This often leads to diagnostic uncertainly. Our objective was to develop a method for differentiating whether a coagulase-negative Staphylococcus sp. positive blood culture represents bacteremia or contamination based on positive bottle detection pattern and time to positivity (TTP). METHODS: This study included 155 and 51 adults with positive blood cultures for Staphylococcus epidermidis and Staphylococcus hominis, respectively, over a three-year period from 2016 to 2018. Positive blood culture cases were categorized as either bacteremia or contamination based on the clinically available information, and the detection pattern and TTP in each category were investigated. RESULTS: A total of 57, 92, and 6 S. epidermidis positive blood cultures were categorized as bacteremia, contamination, and undetermined, respectively, whereas 15 and 36 S. hominis positive blood cultures were categorized as bacteremia and contamination, respectively. For positive blood cultures categorized as bacteremia, all four bottles in two sets of blood cultures were positive in 47/47 S. epidermidis and 14/14 S. hominis, respectively, whereas either one bottle in each of two sets or three bottles in two sets were positive in 10/19 S. epidermidis and 1/4 S. hominis, respectively; most of those TTPs were <48 h. Among them, the TTP in catheter-related blood stream infection was <24 h. CONCLUSION: Although clinical assessment is crucial to differentiate between bacteremia and contamination, a combination of positive bottle detection pattern and TTP is a valuable diagnostic auxiliary tool.

Antimicrobial Resistance Profiles and Molecular Characteristics of Coagulase-Negative Staphylococci Isolated from Two Tertiary Hospitals Before and 15 Years After Implementation of the Separation of Drug Prescribing and Dispensing Policy of Korea.

This study compared changes in antimicrobial susceptibilities and molecular characteristics of coagulase-negative staphylococci (CNS) between the year 2000 and the year 2014-2015 to evaluate the policy of separating drug prescribing and dispensing in Korea. We obtained 68 CNS clinical isolates from two tertiary general hospitals before (the year 2000; n = 25) and after (the year 2014 - 2015; n = 43) implementation of the separation. Isolates were identified as Staphylococcus capitis, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus hominis, Staphylococcus saprophyticus, and Staphylococcus warneri. When minimal inhibitory concentrations of 14 antimicrobials were applied to isolates, resistance rates to gentamicin and oxacillin in 2000 were significantly higher than in 2014-2015 (p < 0.05). Fifty-seven isolates were methicillin-resistant CNS (MR-CNS), 42 of which were also multidrug resistant; overall, multidrug resistance decreased from 72% in the year 2000 to 55.8% in 2014-2015. Staphylococcal cassette chromosome mec (SCCmec) type III was the dominant type of MR-CNS in the year 2000, while SCCmec type IV was the dominant type in 2014-2015. Twenty-five sequence types (STs) were identified; ST2 appeared most frequently in both periods. After 15 years of implementation of this policy, multidrug resistance as well as methicillin and gentamicin resistance in CNS decreased, but not resistance to other antibiotics. Long-term surveillance at both genotypic and phenotypic levels of various species is necessary for further evaluation of this policy.

Sonication of antibiotic loaded cement spacers: A valuable technique for detection of infection persistence in two-stage revision for infected joint arthroplasty.

We evaluated the diagnostic utility of sonication of antibiotic loaded cement spacers comparing with periprosthetic tissue cultures for the detection of persisting infection in 14 patients undergoing staged procedures. Sonication improved microbial detection of intraoperative cultures from 14.2% to 28.5% (P = 0.481). Routine sonication of spacers is recommended.

Biosorption of heavy metals by a lead (Pb) resistant bacterium, Staphylococcus hominis strain AMB-2.

In the present study, a lead (Pb)-resistant bacterium, Staphylococcus hominis strain AMB-2 was isolated from Mandoli industrial area, Delhi and selected for heavy metal biosorption considering multiple heavy metal resistance. In the batch experiment, both living and dead biomasses of strain AMB-2 showed biosorption of Pb and cadmium (Cd) in single and binary systems as analyzed through Inductively coupled plasma-optical emission spectrometry. Living biomass exhibited more biosorption of metals than dead biomass in both single and binary systems. However, in the binary system, metals competed for the attachment sites on the bacterial surface, where Pb got more preference over Cd for the same. The underlying mechanism for the biosorption was attachment of the metal ions through functional groups onto the surface of the biomass as revealed by scanning electron microscope-energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction. Conclusively, this study displayed an effective biotreatment of Pb and Cd from aqueous medium using a low-cost biosorbent prepared from S. hominis strain AMB-2 considering biosafety of microorganisms and an eco-friendly approach.

Understanding the microbial basis of body odor in pre-pubescent children and teenagers.

BACKGROUND: Even though human sweat is odorless, bacterial growth and decomposition of specific odor precursors in it is believed to give rise to body odor in humans. While mechanisms of odor generation have been widely studied in adults, little is known for teenagers and pre-pubescent children who have distinct sweat composition from immature apocrine and sebaceous glands, but are arguably more susceptible to the social and psychological impact of malodor. RESULTS: We integrated information from whole microbiome analysis of multiple skin sites (underarm, neck, and head) and multiple time points (1 h and 8 h after bath), analyzing 180 samples in total to perform the largest metagenome-wide association study to date on malodor. Significant positive correlations were observed between odor intensity and the relative abundance of Staphylococcus hominis, Staphylococcus epidermidis, and Cutibacterium avidum, as well as negative correlation with Acinetobacter schindleri and Cutibacterium species. Metabolic pathway analysis highlighted the association of isovaleric and acetic acid production (sour odor) from enriched S. epidermidis (teen underarm) and S. hominis (child neck) enzymes and sulfur production from Staphylococcus species (teen underarm) with odor intensity, in good agreement with observed odor characteristics in pre-pubescent children and teenagers. Experiments with cultures on human and artificial sweat confirmed the ability of S. hominis and S. epidermidis to independently produce malodor with distinct odor characteristics. CONCLUSIONS: These results showcase the power of skin metagenomics to study host-microbial co-metabolic interactions, identifying distinct pathways for odor generation from sweat in pre-pubescent children and teenagers and highlighting key enzymatic targets for intervention.

Rotura de un seudoaneurisma anastomótico de la arteria femoral común tras el diagnóstico erróneo de hernia inguinal / Ruptured Anastomotic Pseudoaneurysm of the Common Femoral Artery After Wrongful Diagnosis of Inguinal Hernia

No disponible

Anti-quorum Sensing Activities of Selected Coral Symbiotic Bacterial Extracts From the South China Sea.

The worldwide increase in antibiotic-resistant pathogens means that identification of alternative antibacterial drug targets and the subsequent development of new treatment strategies are urgently required. One such new target is the quorum sensing (QS) system. Coral microbial consortia harbor an enormous diversity of microbes, and are thus rich sources for isolating novel bioactive and pharmacologically valuable natural products. However, to date, the versatility of their bioactive compounds has not been broadly explored. In this study, about two hundred bacterial colonies were isolated from a coral species (Pocillopora damicornis) and screened for their ability to inhibit QS using the bioreporter strain Chromobacterium violaceum ATCC 12472. Approximately 15% (30 isolates) exhibited anti-QS activity, against the indicator strain. Among them, a typical Gram-positive bacterium, D11 (Staphylococcus hominis) was identified and its anti-QS activity was investigated. Confocal microscopy observations showed that the bacterial extract inhibited the biofilm formation of clinical isolates of wild-type P. aeruginosa PAO1 in a dose-dependent pattern. Chromatographic separation led to the isolation of a potent QS inhibitor that was identified by high-performance liquid chromatography-mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR) spectroscopy as DL-homocysteine thiolactone. Gene expression analyses using RT-PCR showed that strain D11 led to a significant down-regulation of QS regulatory genes (lasI, lasR, rhlI, and rhlR), as well as a virulence-related gene (lasB). From the chemical structure, the target compound (DL-homocysteine thiolactone) is an analog of the acyl-homoserine lactones (AHLs), and we presume that DL-homocysteine thiolactone outcompetes AHL in occupying the receptor and thereby inhibiting QS. Whole-genome sequence analysis of S. hominis D11 revealed the presence of predicted genes involved in the biosynthesis of homocysteine thiolactone. This study indicates that coral microbes are a resource bank for developing QS inhibitors and they will facilitate the discovery of new biotechnologically relevant compounds that could be used instead of traditional antibiotics.

Comparison of the etiological relevance of Staphylococcus haemolyticus and Staphylococcus hominis.

The study was performed to assess potential differences in the etiological relevance of two coagulase-negative staphylococci (CoNS), Staphylococcus haemolyticus and Staphylococcus hominis, in an observational single-center study. Over a 5-year interval, patients in whom there was detected S. haemolyticus or S. hominis of presumed etiological relevance were assessed for the primary endpoint death during hospital stay and the secondary endpoint transfer to an intensive care unit (ICU) after the detection of S. haemolyticus or S. hominis. Patients with S. haemolyticus or S. hominis died in 11.3% (50 out of 444) and 9.5% (60 out of 631) of cases, respectively, and were transferred to ICU after S. haemolyticus and S. hominis detection in 8.7% (19 out of 219) and 11.7% (44 out of 377) of cases, respectively. There was no significance for species-related influence on the primary outcome parameter (P > 0.1), while ICU transfers were more likely for patients with S. hominis detections (P = 0.016). Delayed diagnosis of both CoNS species was associated with an increased probability of death (P = 0.009). The study revealed comparable morbidity caused by S. haemolyticus and S. hominis identified in a clinically relevant context.

Clinical significance of positive Raoultella Ornithinolytica and Staphylococcus hominis cultures in a post lobectomy patient. A case report.

Raoultella Ornithinolytica (RO) is an encapsulated, Gram- negative, nonmotile aerobic rob which was reclassified from Klepsiella genus belonging in the family of Enterobacteriaceae. It is a rare human infection and few cases have been reported in post thoracotomy patients. Here we present a case of a left lower lobectomy patient that was complicated by pleural effusion and high fever with positive sputum cultures of Raoultella Ornithinolytica and positive pleural fluid cultures of Staphylococcus hominis. It is related with aquatic life poisoning. There are few cases reported and even fewer postoperatively. The infection is rare in human therefore the bacteria is still underreported.

Wide dissemination of SCCfusC in fusidic acid-resistant coagulase-negative staphylococci and implication for its spread to methicillin-resistant staphylococcus aureus in Taiwan.

The fusidic acid (FUS) resistance determinants fusB, fusC, fusD and fusF in coagulase-negative staphylococci (CoNS) clinical isolates were examined. Among 208 FUS-resistant isolates, the fusB gene was the most common resistance determinant in each species, except in Staphylococcus hominis subsp. hominis or in species carrying intrinsic fusD or fusF. In S. hominis subsp. hominis, the fusC gene was the major determinant responsible for FUS resistance. To understand the genetic context of fusC in S. hominis subsp. hominis, 31 fusC-positive S. hominis subsp. hominis isolates were examined. Among these isolates, 14 carried SCCfusC, 3 carried an SCC476-like element and 7 carried a new SCC structure (SCC3390). As shown by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) analyses, the S. hominis subsp. hominis clinical isolates showed limited clonality. Taken together, SCCfusC has been found in S. hominis subsp. hominis, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus capitis subsp. ureolyticus and Staphylococcus aureus, suggesting its wide distribution and spread among different species of staphylococci.

An unusual case of unresolving tunnel infection in a patient on continuous ambulatory peritoneal dialysis.

Atypical mycobacteria remain a rare cause of peritoneal dialysis catheter-related tunnel infection (TI) and poses serious risk because of the resistant nature to most antibiotic therapy. Non-tubercular mycobacterial infections lead to chronicity requiring peritoneal dialysis catheter removal. We report an 82-year-old male, with diabetic nephropathy who had a coinfection with Staphylococcus hominis and Mycobacterium abscessus who presented with pus discharge at exit site and TI. He was treated with relocation of the extraperitoneal part of the catheter with a new exit site without catheter removal and multidrug mycobacterial therapy.

Staphylococcus hominis subsp. novobiosepticus, an emerging multidrug-resistant bacterium, as a causative agent of septicaemia in cancer patients.

Staphylococcus hominis subsp. novobiosepticus is a new sub-species of S. hominis, thus dividing S. hominis into subsp. hominis and novobiosepticus. This study was designed to identify subsp. novobiosepticus isolates amongst the S. hominis isolated from blood samples of patients with malignancy and septicaemia and to study their resistance profile. The identification was performed by using three simple tests which differentiated between the two sub-species. It was found that 22.8 per cent of S. hominis isolates belonged to subsp. novobiosepticus.

Amber necklaces: reasons for use and awareness of risk associated with bacterial colonisation.

Parents are increasingly placing amber necklaces on their infants or toddlers to prevent teething pain. The use of the necklaces can pose a risk of death by strangulation, however, there are no data on the potential infectious risk linked to bacterial colonisation associated with the necklaces. We aimed to analyse bacterial colonisation of amber necklaces worn by children during hospital consultations. This prospective observational study included all children wearing a teething necklace at consultation in the Paediatric Dermatology and the Paediatric Emergency Department of our hospital from April to December 2014. The study included 27 children (median age: 10.7 months; 70.4% female). The surface of necklaces underwent bacteriological analyses using three different agar cultures. Parents completed a brief questionnaire to provide reasons for using necklaces and express awareness of risks. One child had a history of impetigo. All necklaces were colonised by bacteria (median: four species per necklace [range: 1-9]); 32 different species were found, the most frequent being coagulase-negative staphylococci (Staphylococcus epidermidis in 88.9% of cases). In three cases, methicillin-sensitive Staphylococcus aureus was found. The most frequent reason for wearing a necklace was to prevent teething pain (n = 17; 63.0%); the necklace was judged effective (moderately/highly effective) in 74.1% of cases, however, 70.4% of parents considered the use of the necklace to be risky. Amber necklaces may be highly colonised by commensal germs of the skin, mainly coagulase-negative staphylococci. Although these bacteria are saprophytes, they may become pathogenic in particular conditions.

[Ophthalmoplegia without severe painful eyelid swelling in acute dacryoadenitis: a case report].

Here, we present a case of right eyelid drooping in a 79-year-old man. Neurological examination revealed ptosis of the right eye without severe painful eyelid swelling and redness. An ocular motility examination of the right eye revealed upward limitation and downward overshoot. The results of routine blood examinations were within normal limits, and no autoantibodies were detected. Orbital magnetic resonance images revealed mild right eyelid swelling and lacrimal gland enlargement, indicating orbital inflammation. The ocular discharge was positive for Staphylococcus hominis by culture and the patient was diagnosed as having acute dacryoadenitis. Treatment with topical and systemic administration of antibiotics rapidly improved symptoms. Ocular infection is not usually suspected in the absence of local severe painful swelling and redness, and painless acute dacryoadenitis presenting as ophthalmoplegia and ptosis may be misdiagnosed. Orbital inflammation may rapidly progress to orbital cellulitis with treatment delay, which may also lead to aggravation of ophthalmic prognosis. Therefore, neurologists should be aware of the possibility of acute dacryoadenitis occurring without the local severe inflammatory findings mimicking neurological diseases, and acute dacryoadenitis should be considered in patients with ophthalmoplegia even in the absence of severe painful eyelid swelling and redness.

Genotypic Diversity of Methicillin-Resistant Coagulase-Negative Staphylococci Isolated from Inpatients and Outpatients.

We investigated the prevalence of methicillin-resistant coagulase-negative staphylococci (MRCoNS) isolated from hospitalized patients and outpatients (OP). Out of 350 staphylococcal isolates collected from three hospitals, 190 were coagulase-negative staphylococci (CoNS). These isolates were subjected to antimicrobial susceptibility tests, detection of mecA, and pulsed-field gel electrophoresis (PFGE) typing. Among the 190 isolated CoNS, Staphylococcus epidermidis (47.3%) and Staphylococcus haemolyticus (44.2%) were the most prevalent species. Other CoNS species that were isolated were Staphylococcus saprophyticus (2.1%), Staphylococcus warneri (2.1%), Staphylococcus simulans (1.6%), Staphylococcus capitis (1.1%), Staphylococcus schleiferi (1.1%), and Staphylococcus hominis (0.5%). The rate of resistance to methicillin was 60% with 58 (50%) S. epidermidis and 55 (49%) S. haemolyticus. The rate of resistance to 13 antibiotics tested with the lowest and highest to chloramphenicol and penicillin, respectively. High clonal diversity with different PFGE patterns was obtained for methicillin-resistant S. epidermidis and S. haemolyticus by 32 and 31 types, respectively. Our results indicated that the dissemination of MRCoNS is widespread in Tehran. The majority of these isolates showed distinct genotyping patterns. At the same time, the common patterns were found among the MRCoNS obtained from outpatient and inpatient isolates, suggestive of an epidemiological link.

Isolated Pulmonary Valve Endocarditis.

Endocarditis of only the pulmonary valve is a very rare finding and is often missed during echocardiographic evaluation due to limited views of the pulmonary valve and a low index of suspicion. We report 2 cases of pulmonary valve endocarditis (PVE), highlighting the importance of echocardiography in the assessment of the infected pulmonary valve. In addition, we review the published case reports of isolated PVE from 1979 to 2013 in order to study the role of echocardiography in the diagnosis of pulmonary valve masses.