Epidemiology and outcomes of hospital-acquired bloodstream infections in intensive care unit patients: the EUROBACT-2 international cohort study

PURPOSE

In the critically ill, hospital-acquired bloodstream infections (HA-BSI) are associated with significant mortality. Granular data are required for optimizing management, and developing guidelines and clinical trials.

METHODS

We carried out a prospective international cohort study of adult patients (≥ 18 years of age) with HA-BSI treated in intensive care units (ICUs) between June 2019 and February 2021.

RESULTS

2600 patients from 333 ICUs in 52 countries were included. 78% HA-BSI were ICU-acquired. Median Sequential Organ Failure Assessment (SOFA) score was 8 [IQR 5; 11] at HA-BSI diagnosis. Most frequent sources of infection included pneumonia (26.7%) and intravascular catheters (26.4%). Most frequent pathogens were Gram-negative bacteria (59.0%), predominantly Klebsiella spp. (27.9%), Acinetobacter spp. (20.3%), Escherichia coli (15.8%), and Pseudomonas spp. (14.3%). Carbapenem resistance was present in 37.8%, 84.6%, 7.4%, and 33.2%, respectively. Difficult-to-treat resistance (DTR) was present in 23.5% and pan-drug resistance in 1.5%. Antimicrobial therapy was deemed adequate within 24 h for 51.5%. Antimicrobial resistance was associated with longer delays to adequate antimicrobial therapy. Source control was needed in 52.5% but not achieved in 18.2%. Mortality was 37.1%, and only 16.1% had been discharged alive from hospital by day-28.

CONCLUSIONS

HA-BSI was frequently caused by Gram-negative, carbapenem-resistant and DTR pathogens. Antimicrobial resistance led to delays in adequate antimicrobial therapy. Mortality was high, and at day-28 only a minority of the patients were discharged alive from the hospital. Prevention of antimicrobial resistance and focusing on adequate antimicrobial therapy and source control are important to optimize patient management and outcomes.

Micro-anatomical characterization of vertebral curvatures in Senegalese sole Solea senegalensis

The micro-anatomical changes associated with lordotic and kyphotic vertebral curvatures (VC) in juvenile and adult Senegalese sole Solea senegalensis are described. In addition, it is demonstrated that the tissue and cellular structures of individual vertebrae can be severely affected. Two main conformations were found in deformed juvenile specimens: flattened vertebrae with dorso-ventral compression and trapezoidal vertebrae forming concave and convex sides under compressive and tensile stresses. Histological analyses revealed the occurrence of an ectopic cartilaginous tissue within the acellular bone, both in juveniles and adults, possibly to cope with altered mechanical stress in deformed vertebrae. The results suggest that the alteration in loading to which curved vertebral columns are subjected might trigger vertebral reshaping and differentiation of cells towards this ectopic tissue. In addition, mesenchymal cells appear to play an important role in its formation. It is here proposed that the acellular bone of S. senegalensis is capable of adaptively responding to altered loading regimes at the structural level by reshaping vertebrae and at the micro-anatomical level by recruiting chondrocyte-like cells to areas of altered mechanical stress.

Fabrication of phospholipid-xanthan microcapsules by combining microfluidics with self-assembly

We report the synthesis of an amphiphilic polysaccharide, a phospholipid (1,2-dioleoyl-sn-glycero-phosphoetilamine, DOPE) conjugated with the anionic xanthan gum, and its ability to spontaneously self-assemble under mild aqueous conditions. This work also aimed to apply a microfluidic platform that can precisely fabricate microsized and monodispersed capsules for cell encapsulation. Stable hollow capsular structures were obtained by the generation of homogeneous spherical droplets of the self-assembled polymer in the microfluidic device through the formation of a water-in-oil emulsion, followed by the stabilization of the polymer aggregates in a separate collection vessel containing phosphate-buffered saline (physiological ionic strength and pH). The properties (size, morphology, permeability) and performance (stability) of the obtained microcapsules were studied, as well their ability to support the viability, function and proliferation of encapsulated cells. ATDC5 cells were encapsulated within the capsules and shown to remain viable, evidencing increased cellular metabolic activity over 21 days of in vitro culture. By combining microfluidic droplet generation and self-assembly of xanthan-DOPE, we were able to fabricate microcapsules that provided an adequate environment for cells to survive and proliferate.

Infliximab for treating sarcoidosis patients, Portuguese experience

Despite aggressive treatment, sarcoidosis may be debilitating and progressive. The role of tumor necrosis factor (TNF)-a in the genesis of granulomas is ambiguous. It has proven to be critical in the formation and maintenance of granulomatous inflammation and its antagonist, Infliximab, has therefore been used with success in the treatment of patients with sarcoidosis. There are, however, reports of onset of sarcoidosis in patients in treatment for other conditions and that had no outbursts before submission to this therapy. We used Infliximab in the treatment of patients with sarcoidosis who either didn't respond to corticosteroids and other conventional drugs or developed unacceptable side effects to these drugs. The initial dose was 5mg/Kg body weight and subsequent doses were given at weeks 2, 4 and then every other 8 weeks for a total period of one year. We treated ten patients with biopsy proven sarcoidosis, five men and five women, with a mean age of 47.1 years ranging from 28 to 63 years of age. Three patients had severe neurological symptoms, two had hepatic cirrhosis, one had granulomatous inflammation of the lachrymal gland and had already been submitted to many surgeries, one had extensive pulmonary involvement (stage III), one had disfiguring lupus pernio and two presented disabling cutaneous nodules. In four patients the dosage of corticosteroids or other immunosuppressive drugs was suspended, in three the dosage was reduced and in one, corticosteroids were added to the Infliximab therapy. In five of the patients there was a significant improvement. One of the patients with neurological symptoms displayed a complete recovery, while another had significant improvement of vision deficit enabling her to read again. Two patients withdrew from therapy, one due to lack of improvement of neurological symptoms and the other due to the onset of organizing pneumonia spawned by Infliximab. Two patients developed anti-histone antibodies during treatment. Infliximab seems effective in treating patients who are either refractory or develop side effects to a standard regimen of corticosteroids and immunosuppressive agents. These patients, treated with Infliximab, should be under tight surveillance in order to quickly identify possible secondary effects.

Intravascular pulmonary lymphoma with good response to treatment. A case report

Intravascular lymphoma is a very rare form of large B cell non-Hodgkin's lymphoma, characterised by the presence of lymphoma cells in the lumina of small vessels only, particularly in the capillaries. We report a 54 year-old female non-smoker, admitted to hospital for further examination of a four month long clinical condition involving high fever, night sweats, unqualified weight loss and progressive dyspnea. Patient's temperature was 38.5 degrees C, pulse 100/min and respiratory 22 cycles/min. Patient's haemoglobin was 9.4 g/dL, she had leukocytosis, elevated LDH and arterial blood gas analysis with moderate hypoxaemia (FiO2 1l/m: PaO2-63.6 mm Hg). Chest X-ray revealed diffuse interstitial changes. All the possible causes of unknown origin fever were excluded. Diagnosis was made through lung biopsy and treatment with combined chemotherapy and rituximab was prescribed leading to a 48 hours clinical remission. We present this case to show how difficult this diagnosis can be and how a good response to therapy is possible.

Changes in the clonal nature and antibiotic resistance profiles of methicillin-resistant Staphylococcus aureus isolates associated with spread of the EMRSA-15 clone in a tertiary care Portuguese hospital

Two hundred eighty methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates recovered from a tertiary care hospital in Oporto, Portugal, between 2003 and 2005 were studied by a combination of molecular typing techniques in order to investigate the genetic backgrounds associated with the changes in the resistance phenotypes observed since 2001 and compare them to those previously found in the hospital. All MRSA isolates were grouped into resistance profiles for a panel of seven antibiotics and characterized by pulsed-field gel electrophoresis (PFGE) and SCCmec (staphylococcal cassette chromosome mec) typing. Representative isolates of PFGE types were further studied by spa typing and multilocus sequence typing. Our findings clearly document that the increasing isolation of nonmultiresistant MRSA strains was associated with the decline (from 69% in 1996 to 2000 to 12% in 2003 to 2005) and massive replacement of the multiresistant Brazilian clone (ST239-IIIA) by the epidemic EMRSA-15 clone (ST22-IV), in which resistance to antibiotics other than beta-lactams is very rare, as the major clone (80% of isolates). The Iberian clone (ST247-IA), a major clone in 1992 to 1993, was represented in the present study by just one isolate. Two other pandemic MRSA clones were detected, as sporadic isolates, for the first time in our hospital: the New York/Japan (ST5-II) and the EMRSA-16 (ST36-II) clones. Furthermore, the pattern of susceptibility of MRSA isolates both to gentamicin and to trimethoprim-sulfamethoxazole was shown to be an excellent phenotypic marker for the discrimination of the EMRSA-15 clone from other nonmultiresistant MRSA clones present in our hospital.

[Video-assisted thoracic surgery in the diagnosis of interstitial diffuse pulmonary diseases]

Interstitial lung diseases are best diagnosed by surgical lung biopsy. Videoassisted thoracoscopy (VATS) is less aggressive than open lung thoracotomy and its development is associated with an increased number of lung biopsies. Between July 1994 and July 2004 we performed 70 VATS biopsies for interstitial lung disease patients. Only one biopsy was considered inconclusive (1.4%). The remainder 69 (98.6%) established a final diagnosis. The results in our series show that VATS lung biopsy is a safe method with low mortality and morbidity and an excellent rentability.

Radiation damping in real time

We study the nonequilibrium dynamics of a charge interacting with its own radiation, which originates the radiation damping. The real-time equation of motion for the charge and the associated Langevin equation is found in classical limit. The equation of motion for the charge allows one to obtain the frequency-dependent coefficient of friction. In the lowest order we find that although the coefficient of static friction vanishes, there is dynamical dissipation represented by a non-Markovian dissipative kernel.

First report of Lutzomyia (Nyssomyia) umbratilis Ward & Frahia, 1977 outside of Amazonian Region, in Recife, State of Pernambuco, Brazil (Diptera: Psychodidae: Phlebotominae)

Lutzomyia umbratilis, a known vector of Leishmania guyanensis in the north of Amazon basin, has been exclusively found in the Amazonian region. Here we report for the first time the occurrence of this species in northeastern Brazil. The epidemiological importance of the occurrence of this species in the Atlantic Forest is commented.