High-risk international clones ST66, ST171 and ST78 of Enterobacter cloacae complex causing blood stream infections in Spain and carrying blaOXA-48 with or without mcr-9.

BACKGROUND: In the last years, Enterobacter cloacae complex has become an important threat associated with nosocomial infections (including bacteraemia). These bacteria have the ability to acquire mobile genetic elements with antimicrobial resistance genes, reducing the number of therapies available for treatment of the infections they cause. Multidrug resistant isolates of the E. cloacae complex have been causing blood stream infections in a hospital in northern Spain. The aim of this study was to report the spread of E. cloacae complex isolates carrying blaOXA-48 with or without mcr-9 which were involved in blood stream infections, in a Spanish hospital. METHODS: All Enterobacter spp. isolates recovered from blood cultures of patients admitted to a tertiary Spanish hospital, over a five-year period were recovered. Of those, OXA-48-producing isolates were selected for further analysis (19 E. xiangfangensis isolates and a single E. hoffmannii). Bacterial identification, antimicrobial susceptibility, DNA sequencing, molecular typing, resistome analysis and plasmid characterization was performed. RESULTS: 20 isolates were positive for blaOXA-48, harbored by IncL/M plasmids. They belonged to the international high-risk clones ST66, ST171 and ST78. They produced the extended-spectrum ß-lactamases CTX-M-15 and/or CTX-M-9 and 40 % of them (n = 8) also carried the mcr-9 gene, located on IncHI2 plasmids. However, they were susceptible to colistin. CONCLUSION: The presence of blaOXA-48, together with at least one blaCTX-M gene in our multidrug resistant high-risk E. cloacae complex clones is worrisome. Also, the additional presence of mcr-9 in some of them is of concern as it could potentially be transferred into other hosts or acquire mutations that might led to emerging colistin resistance. Surveillance systems are essential to detect these difficult-to-treat bacteria which, apart from causing live-threatening infections, can spread important resistance threats.

Evaluation of 16S rDNA Heart Tissue PCR as a Complement to Blood Cultures for the Routine Etiological Diagnosis of Infective Endocarditis.

Identification of the causative pathogen is required to optimize the effective therapy in infective endocarditis (IE). The aim of this study was to assess a 16S rDNA PCR to identify bacteria from heart valve tissues and to evaluate its usefulness as a complement to blood and removed valves cultures. A total of 266 patients diagnosed with IE from January 2015 to December 2019 were evaluated. Results between 16S rDNA PCR from heart valve tissues were compared with microbiological cultures. Blood cultures were positive in 83.5% of patients diagnosed with IE, while 39.6% and 71.8% of the evaluated heart valve samples were positive by culture and 16S rDNA PCR, respectively. For 32 (12%) patients, 16S rDNA tissue PCR provided valuable information supporting the results of blood cultures in the case of bacteria characteristic from the skin microbiota. Additionally, a microorganism was identified by using 16S rDNA PCR in 36% of blood culture-negative cases. The present study reveals that molecular diagnosis using 16S rDNA tissue PCR provides complementary information for the diagnosis of IE, and it should be recommended in surgical endocarditis, especially when blood cultures are negative.

Sex differences in hospitalized adult patients with cellulitis: A prospective, multicenter study.

OBJECTIVES: Sex differences in adult cellulitis, a frequent cause of hospitalization, have not been analyzed. These differences were investigated in a large cellulitis series. METHODS: This was a prospective observational study of 606 Spanish hospitalized cellulitis patients. Different comorbidities, clinical, diagnostic, and treatment data were compared between the sexes. Multiple logistic regression modeling was performed to determine the variables independently associated with sex. RESULTS: Overall 606 adult cellulitis patients were enrolled; 314 (51.8%) were male and 292 (48.2%) were female. Females were older (mean age 68.8 vs 58.9 years, p < 0.0001), less likely to have prior wounds (p = 0.02), and more likely to have venous insufficiency (p = 0.0002) and edema/lymphedema (p = 0.0003) than males. The location of the infection differed between the sexes (p = 0.02). Males were more likely to have positive pus cultures (p = 0.0008), the causing agent identified (p = 0.04), and higher rates of Staphylococcus aureus infection (p = 0.04) and received longer antibiotic treatment (p = 0.03). Factors independently associated with female sex in the multivariate analysis were older age (p < 0.0001), prior cellulitis (p = 0.01), presence of edema/lymphedema as the predisposing factor (p = 0.004), negative versus positive pus culture (p = 0.0002), and location of cellulitis other than in the lower extremities (p = 0.035). CONCLUSIONS: Differences between male and female patients with cellulitis were age, recurrence, presence of edema/lymphedema, positivity of pus culture, and topography of the infection.

In vitro activity of ceftaroline and ceftobiprole against clinical isolates of Gram-positive bacteria from infective endocarditis: are these drugs potential options for the initial management of this disease?

The in vitro activity of ceftaroline and ceftobiprole was assessed against 77 Gram-positive bacterial isolates recovered from patients diagnosed with infective endocarditis (IE). Our data confirm that these drugs are highly in vitro active against the most common agents of IE including methicillin-resistant Staphylococcus aureus, methicillin-resistant coagulase-negative staphylococci, and Streptococcus spp., with no significant differences between them. Also, ceftaroline and ceftobiprole have demonstrated a good activity against Enterococcus faecalis (MIC90 0.75 µg/mL and 0.5 µg/mL, respectively). The spectrum of these drugs together with the in vitro and in vivo data on them related with IE published in the scientific literature places them as potential options for the initial management of this disease.

Ethambutol-resistant Mycobacterium kansasii cervical lymphadenitis in an immunocompetent adult patient: A case report and literature review.

Mycobacterium kansasii extrapulmonary infections are infrequent in immunocompetent adults. Rifampin (RIF), clarithromycin (CLR), isoniazid (INH) and ethambutol (EMB) are included in all the standard regimens against M.kansasii. We report a case of a healthy 65-year-old male farmer who presented with isolated right supraclavicular lymphadenopathy. The lymph node FNA showed acid-fast-bacilli and granulomatous inflammation. Quantiferon TB Gold test, HIV serology, and functional immunological studies were all negative or normal. He was put on a standard 4 drugs anti-tuberculous regimen that was switched to RIF + CLR+ INH after the Microbiology lab demonstrated an EMB-resistant Mycobacterium kansasii isotype I strain. The patient was cured after 12 months of therapy. This is the 6th reported case of M. kansasii extrapulmonary lymphadenitis in an immunocompetent adult and the 2nd showing EMB resistance in the world literature. Antimycobacterial regimens against M. kansasii, classically resistant to pyrazinamide (PZA) might also exclude EMB due to its increasing resistance in Europe. A 612 months therapy with at least 2 effective antimycobacterial drugs including RIF + CLR might be enough to treat extrapulmonary M. kansasii infections in immunocompetents.

Concentrations of Pneumococcal IgA and IgM are compromised in some individuals with antibody deficiencies.

The response to pneumococcal vaccination is assessed by measurement of antigen specific IgG only and is compromised in a number of antibody deficiencies. We measured the concentrations of Pneumococcal IgA and IgM in individuals with both normal and abnormal pneumococcal capsular polysaccharide (PCP) IgG concentrations. A higher number of individuals had abnormal pre-vaccination IgA and IgM concentrations below the lower limit of the normal range compared to the control group. Post vaccination a lower number of individuals had IgA and IgM concentrations below the upper limit of the normal range compared to the control group. Non responders had a higher percentage of individuals with a prior history of infection. In addition, individuals with a history of prior infection had lower pre- and post-vaccination concentrations of PCP IgG, IgA, and IgM. Post-vaccination IgA and IgM concentrations identified four groups of responses which correlated with prior history of infection. A higher percentage of individuals with abnormal PCP IgA and IgM concentrations had a history of prior infection compared to the percentage of individuals with normal concentrations. In individuals with an antibody deficiency, measurement of Pneumococcal IgA and IgM correlates with the number of individuals with prior history of infection.