Acid-fast bacteria as causative agents of skin and soft tissue infections: case presentations and literature review

Acid-fast bacteria can be implicated in skin and soft tissue infections. Diagnostic identification can be challenging or not feasible by routine laboratory techniques, especially if there is no access to the Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) technology. Here, we present two cases of skin and soft tissue infections caused by two different acid-fast bacteria, Nocardia brasiliensis and Mycobacterium marinum. They both grew on Löwenstein–Jensen medium, Sabouraud agar medium and blood agar medium. Both bacteria appeared acid-fast by Ziehl–Neelsen stain and Gram-positive by Gram stain. The identification was performed by MALDI-TOF MS and gene analysis. N. brasiliensis and nontuberculous mycobacterium M. marinum represent rare pathogens that cause severe skin and soft tissue infections. Failure to identify the causative agent and subsequent inappropriate or inadequate treatment may lead to severe complications or even disseminated disease, especially in immunocompromised individuals

Early KPC-Producing Klebsiella pneumoniae Bacteremia among Intensive Care Unit Patients Non-Colonized upon Admission

Among 140 patients colonized by KPC-producing Klebsiella pneumoniae (KPC-Kp) between fourth and seventh day of Intensive Care Unit stay, 24 developed bacteraemia immediately after colonization. Colistin-resistance of the colonizing isolate was the factor significantly associated with early KPC-Kp bacteraemia (P < 0.001; OR 6.6, 95% CI 2.4–18.4), a worrisome finding since infections by colistin-resistant isolates is associated with increased mortality due to limited remaining therapeutic options

ELECTROPHORETIC PROFILES AND NEUTRAL SUGAR COMPOSITION OF L.P.S AND SLIME FROM A SMOOTH PSEUDOMONAS AERUGINOSA STRAIN AND ITS ROUGH MUTANTS

LIPOPOLYSACCHARIDE (LPS) SLIME AND OUTER MEMBRANES WERE OBTAINED FROM A SMOOTH NON MUCOID PSEUDOMONAS AERUGINOSA STRAIN PAC-IR AND ITS TWO ROUGH MUTANTS PAC 557 AND PAC 605. ELECTROPHORETIC ANALYSIS ON SDS- POLYACRYLAMIDE GELS AND STRAINING WITH SILVER AND COOMASSIE BLUE SHOWED DIFFERENT PROFILES BETWEEN LPS SLIME AND OUTER MEMBRANES IN ALL THREE STRAINS. COMPARATIVE ANALYSIS OF THE SACCHARIDE MOIETY, BETWEEN LPS AND SLIME OF EACH STRAIN BY HPLC DEMONSTRATED THAT THE SACCHARIDE MOIETY OF SLIME HAS DIFFERENT COMPOSITION FROM THAT OF LPS. SIX MENTALSUGARS RHAMMOSE, FUCOSE, XYLOSE, MANNOSE, GALACTOSE AND GLUCOSE WERE IDENTIFIED IN ALL THREE SLIMES, THOUGH IN DIFFERENT AMOUNTS MANNOSE AND GALACTOSE WERE NOT FOUND IN THE SMOOTH LPS WHERE AS ONLY RHAMMOSE AND GLUCOSE WERE IDENTIFIED IN THE LPS OF THE ROUGH STRAINS-COMPARATIVE ANALYSIS OF THE LIPID MOIETY BETWEENLPS AND SLIME IN ALL THREE STRAIN WITH GAS CHROMATOGRAPHY AND MASS SPECTROSCOPY INDICATED THAT LIPID MOIETY HAD NO QUALITATIVE DIFFERENCES CONCERNING THE LIPID ACIDS. FIVE LIPID ACIDS WERE IDENTIFIED IN ALL THREE SLIMES AND LPSS (-C12),2OH(-C12), (- C14), (-C16), (-C18) AND ITS ISOMERIC FORMS. AFTER GEL FILTRATION OF ALL THREE SLIMES THE POLYSACCHARIDE OBTAINS FROM THE CARBOHYDRATE PEAK FRACTION WAS FOUND TO BE PROTEIN FREE. BY GEL FILTRATION THE MOLECULAR SIZE OF THEPOLYSACCHARIDES WAS ESTIMATED TO BE ABOUT 40.000-100.000 DALTONS. THESE RESULTS SUGGESTS THAT SLIME PRODUCTION IS A COMMON PROPERTY SHARED BY BOTH SMOOTH ANDROUGH P.AERUGINOSA STRAINS. THE SACCHARIDE MOIETY OF SLIME DOES NOT REPRESENT THE SIDE CHAINS OF LPS AND IT IS PROTEIN FREE.ΑΠΟ 3 ΠΡΟΤΥΠΑ ΣΤΕΛΕΧΗ P.AERUGINOSA, ΤΟ SMOOTH ΣΤΕΛΕΧΟΣ PAC-IR ΚΑΙ ΤΑ ROUGH ΣΤΕΛΕΧΗ PAC-557 ΚΑΙ PAC-605 ΠΑΡΕΛΗΦΘΗΣΑΝ ΜΕ ΕΙΔΙΚΗ ΜΕΘΟΔΟΛΟΓΙΑ Ο LPS, Η ΕΞΩΚΥΤΤΑΡΙΑΟΥΣΙΑ (SLIME) ΚΑΙ ΟΙ ΕΞΩΤΕΡΙΚΕΣ ΜΕΜΒΡΑΝΕΣ. ΕΓΙΝΑΝ ΗΛΕΚΤΡΟΦΟΡΗΣΕΙΣ (SDS-PAGE) ΚΑΙ ΧΡΩΣΗΣ COOMASSIE ΕΙΔΙΚΗ ΓΙΑ ΠΡΩΤΕΙΝΕΣ ΚΑΙ AGNO3 ΕΙΔΙΚΗ ΓΙΑ ΛΙΠΟΠΟΛΥΣΑΚΧΑΡΙΤΕΣ (LPS). ΟΙ ΗΛΕΚΤΡΟΦΟΡΗΤΙΚΕΣ ΕΙΚΟΝΕΣ ΤΟΥ SLIME ΔΙΑΦΕΡΟΥΝ ΑΠ'ΑΥΤΕΣ ΤΟΥ LPS ΚΑΙ ΤΗΝ ΕΞΩΤΕΡΙΚΗ ΜΕΜΒΡΑΝΗ. ΑΝΑΛΥΣΙΣ ΤΩΝ ΟΥΔΕΤΕΡΩΝ ΣΑΚΧΑΡΩΝ ΕΔΕΙΞΕ ΟΤΙ ΚΑΙ ΤΑ 3 SLIME ΠΕΡΙΕΧΟΥΝ ΜΕ ΠΟΣΟΤΙΚΕΣ ΔΙΑΦΟΡΕΣ 6 ΣΑΚΧΑΡΑ, ΤΗ ΦΟΥΚΟΖΗ, ΤΗΝ ΞΥΛΟΖΗ, ΤΗ ΜΑΝΟΖΗ,'Η ΤΗ ΓΑΛΑΚΤΟΖΗ. ΑΝΤΙΘΕΤΑ ΜΑΝΟΖΗ ΚΑΙ ΓΑΛΑΚΤΟΖΗ ΔΕΝ ΠΕΡΙΕΧΟΝΤΑΙ ΣΤΟ SMOOTH LPS ΕΝΩ ΟΙ ROUGH LPS ΠΕΡΙΕΧΟΥΝ ΜΟΝΟ ΡΑΜΝΟΖΗ ΚΑΙ ΓΛΥΚΟΖΗ. ΑΝΑΛΥΣΗ ΤΟΥ ΛΙΠΙΔΙΚΟΥ ΣΤΟΙΧΕΙΟΥ ΤΩΝ 3 SLIME ΚΑΙ ΤΩΝ 3 LPS ΕΔΕΙΞΕ ΟΤΙ ΠΟΙΟΤΙΚΑ ΠΕΡΙΕΧΟΥΝ 5 ΙΔΙΑ ΛΙΠΑΡΑ ΟΞΕΑ. ΔΩΔΕΚΑΝΟΙΚΟ ΟΞΥ (- C12), 2OH-ΔΩΔΕΚΑΝΟΙΚΟ (-C12) ΔΕΚΑΤΕΤΡΑΝΙΚΟ ΟΞΥ (-C14), ΔΕΚΑΕΞΑΝΙΚΟ ΟΞΥ (-C16) ΔΕΚΑΟΚΤΑΝΙΚΟ ΟΞΥ (-C18) ΚΑΙ ΤΑ ΙΣΟΜΕΡΗ ΤΟΥ . ΜΕΤΑ ΑΠΟ ΧΡΩΜΑΤΟΓΡΑΦΙΑ ΜΟΡΙΑΚΗΣ ΔΙΗΘΗΣΗΣ ΣΤΑ 3 SLIME Ο ΠΟΛΥΣΑΚΧΑΡΙΤΗΣ ΠΟΥ ΠΑΡΑΛΑΜΒΑΝΕΤΑΙ ΑΠΟΤΗΝ ΥΔΑΤΟΑΝΘΡΑΚΙΚΗ ΚΟΡΥΦΗ, ΔΕΝ ΠΕΡΙΕΧΕΙ ΠΡΩΤΕΙΝΗ ΚΑΙ ΕΙΝΑΙ ΜΟΡΙΑΚΟΥ ΒΑΡΟΥΣ 40.000-100.000 DALTONS. ΑΡΑ Η ΠΑΡΑΓΩΓΗ ΤΟΥ SLIME ΕΙΝΑΙ ΚΟΙΝΗ ΙΔΙΟΤΗΤΑ SMOOTH ΚΑΙ ROUGH ΣΤΕΛΕΧΩΝ P.AERUGINOSA ΚΑΙ ΤΟ ΥΔΑΤΟΑΝΘΡΑΚΙΚΟ ΣΤΟΙΧΕΙΟ ΤΟΥ SLIME ΕΙΝΑΙ ΑΥΤΟΤΕΛΗΣ ΟΥΣΙΑ ΕΛΕΥΘΕΡΗ ΠΡΩΤΕΙΝΩΝ ΠΟΥ ΔΕΝ ΑΠΟΤΕΛΕΙΤΑΙ ΑΠΟ ΤΙΣ ΠΛΕΥΡΙΚΕΣ ΑΛΥΣΙΔΕΣ

Pseudomonas aeruginosa Slime Glycolipoprotein Is a Potent Stimulant of Tumor Necrosis Factor Alpha Gene Expression and Activation of Transcription Activators Nuclear Factor κB and Activator Protein 1 in Human Monocytes

Pseudomonas aeruginosa, an opportunistic pathogen, causes infections associated with a high incidence of morbidity and mortality in immunocompromised hosts. Production of tumor necrosis factor alpha (TNF-α), primarily by cells of monocytic lineage, is a crucial event in the course of these infections. During in vivo infections with P. aeruginosa, both lipopolysaccharide (LPS) and extracellular slime glycolipoprotein (GLP) produced by mucoid and nonmucoid strains are released. In the present study, we sought to explore the relative contributions of these two bacterial products to TNF-α production by human monocytes. To this end, fresh human monocytes and THP-1 human monocytic cells were stimulated with P. aeruginosa LPS or GLP. GLP was found to be a more potent stimulus for TNF-α production (threefold higher) by human monocytes than LPS. Moreover, its effect was comparable to that of viable bacteria. Quantitative mRNA analysis revealed predominantly transcriptional regulation. Electrophoretic mobility shift assays and transfection assays demonstrated activation of NF-κB and activator protein 1 (AP-1). NF-κB activation by GLP was rapid and followed the same time course as that by viable bacteria, suggesting that bacteria could directly activate NF-κB through GLP. Moreover P. aeruginosa GLP induced the formation of AP-1 complex with delayed kinetics compared with NF-κB but much more efficiently than the homologous LPS. These results identify GLP as the most important stimulant for TNF-α production by human monocytes. Activation of NF-κB and AP-1 by P. aeruginosa GLP may be involved not only in TNF-α induction but also in many of the inflammatory responses triggered in the course of infection with P. aeruginosa

Mortality of Pandrug-Resistant <i>Klebsiella pneumoniae</i> Bloodstream Infections in Critically Ill Patients: A Retrospective Cohort of 115 Episodes

Background: The increased frequency of bacteraemias caused by pandrug-resistant Klebsiella pneumoniae (PDR-Kp) has significant implications. The aim of the present study was to identify predictors associated with mortality of PDR-Kp bacteraemias. Methods: Patients with monomicrobial bacteraemia due to PDR-Kp were included. K. pneumoniae was considered PDR if it showed resistance to all available groups of antibiotics. Primary outcome was 30-day mortality. Minimum inhibitory concentrations (MICs) of meropenem, tigecycline, fosfomycin, and ceftazidime/avibactam were determined by Etest, whereas for colistin, the broth microdilution method was applied. blaKPC, blaVIM, blaNDM, and blaOXA genes were detected by PCR. Results: Among 115 PDR-Kp bacteraemias, the majority of infections were primary bacteraemias (53; 46.1%), followed by catheter-related (35; 30.4%). All isolates were resistant to tested antimicrobials. blaKPC was the most prevalent carbapenemase gene (98 isolates; 85.2%). Thirty-day mortality was 39.1%; among 51 patients with septic shock, 30-day mortality was 54.9%. Multivariate analysis identified the development of septic shock, Charlson comorbidity index, and bacteraemia other than primary or catheter-related as independent predictors of mortality, while a combination of at least three antimicrobials was identified as an independent predictor of survival. Conclusions: Mortality of PDR-Kp bloodstream infections was high. Administration of at least three antimicrobials might be beneficial for infections in critically ill patients caused by such pathogens

Prevalence of anti-HAV antibodies in multitransfused patients with beta-thalassemia

AIM: To detect the prevalence of anti-HAV IgG antibodies in adult multitransfused beta-thalassemic patients