Native Valve Endocarditis Caused by Nocardia asteroides in an Immunocompetent Host: A Case Report and a Review of the Literature.

Nocardia species are a rare cause of infective endocarditis (IE). We describe a case of native valve endocarditis caused by Nocardia asteroides in a 38-year-old Hispanic male with no apparent environmental exposures or risk factors for IE. Transesophageal echocardiography revealed severe mitral regurgitation, prompting emergent replacement of the valve. Nocardia asteroides were isolated from the tissue culture of the mitral valve. MRI of the brain also demonstrated innumerable micronodular intra-axial lesions throughout the brain, consistent with disseminated nocardiosis. The patient was treated with intravenous trimethoprim/sulfamethoxazole, meropenem, and amikacin for a six-week course, followed by oral trimethoprim/sulfamethoxazole and minocycline for 12 months. Follow-up after 18 months revealed no evidence of relapse. Although several cases of endocarditis due to Nocardia asteroides have been reported in immunocompromised hosts, to the best of our knowledge we believe the present case is the first to describe native valve endocarditis by Nocardia asteroides in an immunocompetent host with no apparent risk factors for IE.

Early use of tocilizumab in the prevention of adult respiratory failure in SARS-CoV-2 infections and the utilization of interleukin-6 levels in the management.

Respiratory failure in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection appears related to cytokine release syndrome that often results in mechanical ventilation (MV). We investigated the role of tocilizumab (TCZ) on interleukin-6 (IL-6) trends and MV in patients with SARS-CoV-2. In this longitudinal observational study, 112 patients were evaluated from 1 February to 31 May 2020. TCZ was administered followed by methylprednisolone to patients with >3L oxygen requirement and pneumonia severity index score ≤130 with computed tomography scan changes. IL-6, C-reactive protein (CRP), ferritin, lactate dehydrogenase (LDH), D-dimer, and procalcitonin were monitored on days 0, 3, and 6 of therapy. Statistical analyses were performed with significance ≤0.05. Eighty out of 112 SARS-CoV-2-positive patients (45 males, 56.96%; 34 females, 43.04%) were included in this study. Seven patients expired (8.75%) and nine patients required MV (11.25%). Median IL-6 levels pre-administration of TCZ was 342.50 (78.25-666.25) pg/mL compared with post-administration on day 3 (563; 162-783) pg/mL (P < .00001). On day 6, the median dropped to 545 (333.50-678.50) pg/mL compared with day 3 (P = .709). CRP, ferritin, LDH, and D-dimer levels were reduced after TCZ therapy. Early use of TCZ may reduce the need for MV and decrease CRP, ferritin, LDH, and D-dimer levels. The sequential use of methylprednisolone for 72 hours seems to potentiate the effect and prolong the suppression of the cytokine storm. IL-6 levels may be helpful as a prognostic tool.

Proposed Guidelines for the Management of ESBL in Prosthetic Joint Infections.

The aim of this paper is to establish guidelines for the management of extendedspectrum beta-lactamases (ESBL) associated prosthetic joint infections (PJI). This study reviewed 21 patients in the literature documented with ESBL associated PJI. Literature suggests that patients with ESBL PJI are stratified into either early infections (<3 weeks) or late infections (>3 weeks), for which, appropriate laboratory and imaging studies need to be completed. Favorable outcomes require a two-stage revision with an antibiotic-impregnated spacer and a prolonged course of intravenous carbapenem antibiotic.

The human jejunum has an endogenous microbiota that differs from those in the oral cavity and colon.

BACKGROUND: The upper half of the human small intestine, known as the jejunum, is the primary site for absorption of nutrient-derived carbohydrates, amino acids, small peptides, and vitamins. In contrast to the colon, which contains 1011-1012 colony forming units of bacteria per ml (CFU/ml), the normal jejunum generally ranges from 103 to 105 CFU per ml. Because invasive procedures are required to access the jejunum, much less is known about its bacterial microbiota. Bacteria inhabiting the jejunal lumen have been investigated by classical culture techniques, but not by culture-independent metagenomics. RESULTS: The lumen of the upper jejunum was sampled during enteroscopy of 20 research subjects. Culture on aerobic and anaerobic media gave live bacterial counts ranging from 5.8 × 103 CFU/ml to 8.0 × 106 CFU/ml. DNA from the same samples was analyzed by 16S rRNA gene-specific quantitative PCR, yielding values from 1.5 × 105 to 3.1 × 107 bacterial genomes per ml. When calculated for each sample, estimated bacterial viability ranged from effectively 100% to a low of 0.3%. 16S rRNA metagenomic analysis of uncultured bacteria by Illumina MiSeq sequencing gave detailed microbial composition by phylum, genus and species. The genera Streptococcus, Prevotella, Veillonella and Fusobacterium, were especially abundant, as well as non-oral genera including Escherichia, Klebsiella, and Citrobacter. The jejunum was devoid of the genera Alistipes, Ruminococcus, Faecalibacterium, and other extreme anaerobes abundant in the colon. In patients with higher bacterial loads, there was no significant change in microbial species composition. CONCLUSIONS: The jejunal lumen contains a distinctive bacterial population consisting primarily of facultative anaerobes and oxygen-tolerant obligate anaerobes similar to those found in the oral cavity. However, the frequent abundance of Enterobacteriaceae represents a major difference from oral microbiota. Although a few genera are shared with the colon, we found no evidence for retrograde movement of the most abundant colonic microbes to the jejunum. Some individuals had much higher bacterial loads, but this was not correlated with decreases in bacterial species diversity or other evidence of dysbiosis.

Ceftazidime/avibactam: a novel cephalosporin/nonbeta-lactam beta-lactamase inhibitor for the treatment of complicated urinary tract infections and complicated intra-abdominal infections.

There has been greater interest in developing additional antimicrobial agents due to the increasing health care costs and resistance resulting from bacterial pathogens to currently available treatment options. Gram-negative organisms including Enterobacteriaceae and Pseudomonas aeruginosa are some of the most concerning threats due to their resistance mechanisms: extended-spectrum beta-lactamase production and Klebsiella pneumoniae carbapenemase enzymes. Ceftazidime is a third-generation broad-spectrum cephalosporin with activity against P. aeruginosa and avibactam is a novel nonbeta-lactam beta-lactamase inhibitor. Avycaz(®), the trade name for this new combination antibiotic, restores the activity of ceftazidime against some of the previously resistant pathogens. Avycaz was approved in 2015 for the treatment of complicated urinary tract infections, including pyelonephritis, and complicated intra-abdominal infections with the addition of metronidazole in patients with little to no other treatment options. This review article assesses the clinical trials and data that led to the approval of this antibiotic, in addition to its spectrum of activity and limitations.

The Forgotten One: Lemierre's Syndrome Due to Gram-Negative Rods Prevotella Bacteremia.

BACKGROUND: Lemierre's syndrome (LS) is a rare syndrome caused by an acute oropharyngeal infection with metastatic spreading. It was described in 1939 as jugular vein septic thrombophlebitis associated with retropharyngeal infection. Different organisms can cause LS, such as Fusobacterium species, Peptostreptococcus, group B and C, Streptococcus, Staphylococcus, and Enterococcus species, but the most commonly isolated pathogen is Fusobacterium necrophorum, a common oral flora. Management depends on the initial presentation, type of pathogen isolated, and proper selection of antibiotics. CASE REPORT: We report a case of a 22-year-old man with no past medical history, who presented with left jaw pain and progressive left facial area swelling associated with dyspnea. A final diagnosis of LS was made based on criteria of computed tomography (CT) of the neck and the clinical symptoms. The patient was started on broad-spectrum antibiotics. Subsequent imaging of the chest showed pleural effusion with septic emboli. He underwent thoracentesis and chest tube placement. Final blood cultures were remarkable for gram-negative rods - Prevotella anaerobes - which supported the diagnosis of LS. His condition improved, including the dyspnea, and he was discharged on the proper antibiotics coverage with outpatient follow-up. CONCLUSIONS: LS is a rare condition associated with metastatic infection spreading. This syndrome can be associated with further complications, such as pleural effusions and/or empyemas. Early recognition is important to prevent fatal complications and provide adequate antibiotics coverage. We report only the third case in the medical literature of Prevotella-induced LS with a secondary complication of pleural effusion.