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Cureus Jan 2024Nocardiosis is known as an opportunistic infection in immunocompromised hosts. We present to you a case of pleural nocardiosis in a 38-year-old male patient who was a...
Nocardiosis is known as an opportunistic infection in immunocompromised hosts. We present to you a case of pleural nocardiosis in a 38-year-old male patient who was a chronic smoker and presented with a left-sided pleural effusion. He was a known case of thrombocytopenia due to immune thrombocytopenia (ITP) and was on steroid therapy. On admission, he was found to be positive for HIV. Pleural fluid was sent to microbiology, where acid-fast staining with 1% sulfuric acid (HSO)showed acid-fast branching filamentous rods and cultures grew which was resistant to ampicillin, ceftriaxone, imipenem, cotrimoxazole, erythromycin, tetracycline, and susceptible to amikacin, linezolid, and levofloxacin. The isolate was identified as using 16S rRNA gene sequencing. Culture from the chest wall drain grew and Subsequently, the patient developed sepsis, and paired blood cultures grew . Unfortunately, the patient could not survive despite aggressive efforts and died after 40 days of admission.
PubMed: 38344492
DOI: 10.7759/cureus.52071 -
Journal of Clinical Medicine Feb 2024Chest trauma is one of the most serious and difficult injuries, with various complications that can lead to ventilation-perfusion (V/Q) mismatch and systemic hypoxia. We...
Chest trauma is one of the most serious and difficult injuries, with various complications that can lead to ventilation-perfusion (V/Q) mismatch and systemic hypoxia. We are presenting a case of a 53-year-old male with no chronic therapy who was admitted to the Intensive Care Unit due to severe respiratory failure after chest trauma. He developed a right-sided pneumothorax, and then a thoracic drain was placed. On admission, the patient was hemodynamically unstable and tachypneic. He was intubated and mechanically ventilated, febrile (38.9 °C) and unconscious. A lung CT showed massive non-ventilated areas, predominantly in the right lung, guiding repeated therapeutic and diagnostic bronchoalveolar lavages. He was ventilated with PEEP of 10 cmHO with a FiO of 0.6-0.8. Empirical broad-spectrum antimicrobial therapy was immediately initiated. Both high FiO and moderate PEEP were maintained and adjusted according to the current blood gas values and oxygen saturation. He was weaned from mechanical ventilation, and non-invasive oxygenation was continued. After was identified and treated with sulfamethoxazole/trimethoprim, a regression of lung infiltrates was observed. In conclusion, both ventilatory and antibiotic therapy were needed to improve the oxygenation and outcome of the patient with pneumonia and V/Q mismatch.
PubMed: 38337565
DOI: 10.3390/jcm13030871 -
Journal of Global Antimicrobial... Mar 2024Gram-negative pathogens causing respiratory infection in people with cystic fibrosis and bronchiectasis are becoming progressively more resistant to conventional...
OBJECTIVES
Gram-negative pathogens causing respiratory infection in people with cystic fibrosis and bronchiectasis are becoming progressively more resistant to conventional antibiotics. Although cefiderocol is licenced for the treatment of infections due to Gram-negative organisms, there are limited data on the activity of cefiderocol against pathogens associated with chronic respiratory diseases. The aim of this study was to determine the susceptibility of Gram-negative pathogens from cystic fibrosis and bronchiectasis to cefiderocol and comparator antibiotics.
METHODS
Minimal inhibitory concentrations (MICs) of cefiderocol and 15 comparator antibiotics were determined by broth microdilution against 300 respiratory isolates: Burkholderia spp., Stenotrophomonas spp., Achromobacter spp., Ralstonia spp. and Pandoraea spp., and used to calculate the MIC of each antibiotic required to inhibit 50% (MIC) and 90% (MIC) of isolates.
RESULTS
The MIC and MIC of cefiderocol for all 300 isolates tested was 0.25 and 32 mg/L, with 232 (77.3%) isolates having an MIC value ≤2 mg/L. In addition, cefiderocol demonstrated excellent activity against Stenotrophomonas spp. and Achromobacter spp. isolates, with 86.7% and 87.2%, respectively, exhibiting an MIC of 2 mg/L. Tigecycline also demonstrated good activity against all isolates with an MIC of <0.5 mg/L.
CONCLUSIONS
These in vitro data demonstrated that cefiderocol had greater activity than most comparator antibiotics and could be an alternative treatment option for respiratory infection caused by these pathogens that has not responded to first-line therapy.
Topics: Humans; Cefiderocol; Cephalosporins; Cystic Fibrosis; Gram-Negative Bacteria; Drug Resistance, Multiple, Bacterial; Anti-Bacterial Agents; Bronchiectasis; Respiratory Tract Infections
PubMed: 38336228
DOI: 10.1016/j.jgar.2024.01.023 -
Journal of Ophthalmic Inflammation and... Feb 2024To describe a puzzling case of endophthalmitis caused by three unusual bacteria after intravitreal injection, its outcome, and underlying questions.
PURPOSE
To describe a puzzling case of endophthalmitis caused by three unusual bacteria after intravitreal injection, its outcome, and underlying questions.
FINDINGS
A 70-year-old female patient was diagnosed with acute endophthalmitis following intravitreal aflibercept injection for age-related macular degeneration. A standard tap and inject procedure was performed. Microbiological analyses on the anterior chamber and vitreous samples yielded the presence of three non-fermenting Gram-negative rods: Pseudomonas stutzeri, Stenotrophomonas maltophilia, and Ochrobactrum anthropi. The outcome was favorable after intravitreal injections of vancomycin and ceftazidime, with an almost complete recovery of the visual acuity to its baseline level. No potential source of infection was identified.
CONCLUSION
Endophthalmitis following intravitreal injection can be caused by a wide variety of bacteria, including some rare Gram-negative species. They can sometimes co-exist in a single patient, but their virulence may vary greatly. Due to the variable antibiotic susceptibility and frequent multiresistance associated with non-fermenting Gram-negative rods, a prompt microbiological approach is required. Favorable outcome can be achieved with standard management.
PubMed: 38334879
DOI: 10.1186/s12348-023-00376-9 -
Indian Journal of Critical Care... Feb 2024There is a scarcity of studies evaluating the microbial profile, antimicrobial susceptibility, and prevalence of MDR/XDR pathogens causing medical device-associated...
BACKGROUND
There is a scarcity of studies evaluating the microbial profile, antimicrobial susceptibility, and prevalence of MDR/XDR pathogens causing medical device-associated infections (MDAIs). The present study was sought in this regard.
MATERIALS AND METHODS
An ambispective-observational, site-specific, surveillance-based study was performed for a period of 2 years in the intensive care unit (ICU) and high dependency unit (HDU) (medicine/surgery) of a Tertiary-care University Hospital. Three commonly encountered MDAIs including central-line-associated bloodstream infections (CLABSI), catheter-associated urinary tract infections (CAUTI), and ventilator-associated pneumonia (VAP), were targeted.
RESULTS AND CONCLUSION
Of the total 90 patients, 46 (51.1%) were admitted to the ICU (medicine/surgery), and the remaining 44 (48.8%) were admitted to the HDU (medicine/surgery). The median (P-P) age of the total patients was 55 (43.1-62.3) years. Male 61 (67.8%) preponderance was observed. Sixty-two of 90 (68.9%) were immunocompromised. A total of 104 pathogens causing MDAIs were isolated. were commonly isolated multi-drug resistant (MDR) gram-positive pathogens causing MDAIs. Similarly, carba-resistant carba-resistant were commonly isolated MDR gram-negative pathogens causing MDAIs. Five of 9 (55.5%) and three of 9 (33.3%) isolates were found to be extensively drug resistant. Among was the most prevalent fungal pathogen causing CLABSI and CAUTI in patients admitted to ICU/HDU.
HOW TO CITE THIS ARTICLE
Suryawanshi VR, Pawar A, Purandare B, Vijayvargiya N, Sancheti S, Philip S, . Microbial Profile, Antimicrobial Susceptibility, and Prevalence of MDR/XDR Pathogens Causing Medical Device Associated Infections: A Single Center Study. Indian J Crit Care Med 2024;28(2):152-164.
PubMed: 38323246
DOI: 10.5005/jp-journals-10071-24623 -
Microbiology Spectrum Mar 2024species are clinically relevant free-living amoebae (FLA) ubiquitously found in soil and water bodies. Metabolically active trophozoites graze on diverse microbes via...
species are clinically relevant free-living amoebae (FLA) ubiquitously found in soil and water bodies. Metabolically active trophozoites graze on diverse microbes via phagocytosis. However, functional studies on Rab GTPases (Rabs), which are critical for controlling vesicle trafficking and maturation, are scarce for this FLA. This knowledge gap can be partly explained by the limited genetic tools available for cell biology. Here, we developed plasmids to generate fusions of strain Neff proteins to the N- or C-termini of mEGFP and mCherry2. Phylogenomic and structural analyses of the 11 Neff Rab7 paralogs found in the RefSeq assembly revealed that eight of them had non-canonical sequences. After correcting the gene annotation for the Rab7A ortholog, we generated a line stably expressing an mEGFP-Rab7A fusion, demonstrating its correct localization to acidified macropinocytic and phagocytic vacuoles using fluorescence microscopy live cell imaging (LCI). Direct labeling of live ESTM1D_MKCAZ16_6a (Sm18) cells with pHrodo Red, a pH-sensitive dye, demonstrated that they reside within acidified, Rab7A-positive vacuoles. We constructed new mini-Tn7 delivery plasmids and tagged Sm18 with constitutively expressed mScarlet-I. Co-culture experiments of Neff trophozoites with Sm18::mTn7TC1_Pc_mScarlet-I, coupled with LCI and microplate reader assays, demonstrated that Sm18 underwent multiple replication rounds before reaching the extracellular medium via non-lytic exocytosis. We conclude that belongs to the class of bacteria that can use amoeba as an intracellular replication niche within a -containing vacuole that interacts extensively with the endocytic pathway.IMPORTANCEDiverse lineages (genotypes) are of increasing clinical concern, mainly causing amoebic keratitis and granulomatous amebic encephalitis among other infections. ranks among the top 10 most prevalent multidrug-resistant opportunistic nosocomial pathogens and is a recurrent member of the microbiome hosted by and other free-living amoebae. However, little is known about the molecular strategies deployed by for an intracellular lifestyle in amoebae and other professional phagocytes such as macrophages, which allow the bacterium to evade the immune system and the action of antibiotics. Our plasmids and easy-to-use microtiter plate co-culture assays should facilitate investigations into the cellular microbiology of interactions with and other opportunistic pathogens, which may ultimately lead to the discovery of new molecular targets and antimicrobial therapies to combat difficult-to-treat infections caused by these ubiquitous microbes.
Topics: Acanthamoeba castellanii; Stenotrophomonas maltophilia; Vacuoles; Phylogeny; Bacteria
PubMed: 38319117
DOI: 10.1128/spectrum.02988-23 -
JAC-antimicrobial Resistance Feb 2024This study evaluated the activity of cefiderocol, ceftazidime/avibactam, and aztreonam/avibactam against clinically important multidrug-resistant non-fermenting...
BACKGROUND
This study evaluated the activity of cefiderocol, ceftazidime/avibactam, and aztreonam/avibactam against clinically important multidrug-resistant non-fermenting Gram-negative bacilli.
METHODS
Bacteraemic isolates of 126 multidrug-resistant (MDRAB), 110 imipenem-resistant [including 14 difficult-to-treat resistant (DTRPA)], 45 beta-lactam-non-susceptible complex (BCC), 47 levofloxacin or trimethoprim/sulfamethoxazole-non-susceptible and 22 ciprofloxacin-non-susceptible spp. collected between 2019 and 2021 were subjected to MIC determination for cefiderocol, ceftazidime/avibactam and aztreonam/avibactam.
RESULTS
The MICs of cefiderocol for drug-resistant , , BCC, and spp. were 0.25/2, 0.25/1, ≤0.06/≤0.06, ≤0.06/0.25 and >32/>32 mg/L, respectively. Cefiderocol inhibited 94.4% (119/126) of MDRAB, 100% of imipenem-resistant , 100% of DTRPA and 100% of BCC at an MIC ≤4 mg/L, and 97.9% (46/47) of at ≤1 mg/L. Ceftazidime/avibactam inhibited 76.4% (84/110) of imipenem-resistant , 21.4% (3/14) of DTRPA and 68.9% (31/45) of BCC at an MIC ≤8 mg/L. Aztreonam/avibactam had MICs of 16/>32, 8/16 and 4/8 mg/L for imipenem-resistant , BCC and , respectively. At ≤8 mg/L, aztreonam/avibactam inhibited 7.1% (1/14) of DTRPA and 93.6% (44/47) of isolates. spp. demonstrated high MICs for cefiderocol, ceftazidime/avibactam and aztreonam/avibactam, with all MICs and MICs > 32 mg/L.
CONCLUSION
Cefiderocol may serve as an alternative treatment for multidrug-resistant , , BCC and when other antibiotics have been ineffective or intolerable. The role of ceftazidime/avibactam and aztreonam/avibactam in the management of BCC or infections warrants further investigation.
PubMed: 38304722
DOI: 10.1093/jacamr/dlae006 -
Japanese Journal of Infectious Diseases Jan 2024Stenotrophomonas maltophilia is a non-fermenting Gram-negative drug-resistant pathogen causing healthcare-associated infections. Clinical isolates from Mexico were...
Stenotrophomonas maltophilia is a non-fermenting Gram-negative drug-resistant pathogen causing healthcare-associated infections. Clinical isolates from Mexico were assessed for biofilm production by crystal violet staining. Antimicrobial susceptibility was evaluated using the broth microdilution method in planktonic and biofilm cells. The effect of antibiotics on the biofilm was visualized by fluorescence microscopy. Fifty isolates were included in the study, of which 28.0% were biofilm producers (64.2% from blood and 35.7% from respiratory samples). Resistance to levofloxacin (8.0%) and trimethoprim-sulfamethoxazole (44.0%) in planktonic cells increased to 100% in biofilm cells. Bacterial biofilm treated with several concentrations of both antibiotics was completely disrupted. In conclusion, S. maltophilia isolated from blood had higher biofilm production than those from respiratory samples. Resistance to antibiotics increased due to biofilm production. Antibiotic monotherapy might not be the best course of action for the treatment of S. maltophilia infections in Mexico, as they might also be causing biofilm production.
PubMed: 38296539
DOI: 10.7883/yoken.JJID.2023.389 -
Applied and Environmental Microbiology Feb 2024The growing concern arising from viruses with pandemic potential and multi-resistant bacteria responsible for hospital-acquired infections and outbreaks of food...
The growing concern arising from viruses with pandemic potential and multi-resistant bacteria responsible for hospital-acquired infections and outbreaks of food poisoning has led to an increased awareness of indirect contact transmission. This has resulted in a renewed interest to confer antimicrobial properties to commonly used metallic materials. The present work provides a full characterization of optimized fluoride anodic films grown in stainless steel 304L as well as their antimicrobial properties. Antibacterial tests show that the anodic film, composed mainly of chromium and iron fluorides, reduces the count and the percentage of the area covered by 50% and 87.7% for and , respectively. Virologic tests show that the same treatment reduces the infectivity of the coronavirus HCoV-229E-GFP, in comparison with the non-anodized stainless steel 304L.IMPORTANCEThe importance of environmental surfaces as a source of infection is a topic of particular interest today, as many microorganisms can survive on these surfaces and infect humans through direct contact. Modification of these surfaces by anodizing has been shown to be useful for some alloys of medical interest. This work evaluates the effect of anodizing on stainless steel, a metal widely used in a variety of applications. According to the study, the fluoride anodic layers reduce the colonization of the surfaces by both bacteria and viruses, thus reducing the risk of acquiring infections from these sources.
Topics: Humans; Fluorides; Stainless Steel; Fomites; Bacteria; Anti-Infective Agents
PubMed: 38289132
DOI: 10.1128/aem.01892-23 -
Journal of Global Antimicrobial... Mar 2024
Letter in response to first case of persistent Stenotrophomonas maltophilia bacteremia due to septic thrombosis successfully treated with a Cefiderocol-containing regimen.
Topics: Case Reports as Topic; Humans; Cefiderocol; Anti-Bacterial Agents; Gram-Negative Bacterial Infections; Stenotrophomonas maltophilia
PubMed: 38280718
DOI: 10.1016/j.jgar.2024.01.008