Influence of transition from open bay units to single room units in a neonatal intensive care unit on hospital transmission of multi-drug-resistant Enterobacterales.

BACKGROUND: It was shown previously that changing the design of a hospital neonatal intensive care unit (NICU) from open bay units (OBUs) to single room units (SRUs) was not associated with a reduction in Gram-negative multi-drug-resistant organism (MDRO) colonization rates. It was therefore hypothesized that colonization mainly occurs vertically, or through parents and healthcare workers, and not through environmental factors, and that transition to SRUs would not decrease the number of clusters of MDROs with an epidemiological link. To investigate this, core-genome multi-locus sequence typing (cgMLST) was applied on MDROs cultured from infants at the study hospital. METHODS: This retrospective cohort study included all infants carrying MDROs admitted to the NICU of a tertiary care academic hospital 2 years prior to the transition from OBUs to SRUs in May 2017, and 1.5 years after the transition (2018-2020). RESULTS: In total, 55 infants were diagnosed with MDRO carriership. Isolates were available from 49 infants for cgMLST. In the OBU period, one cluster involving four of 20 (20%) infants was identified, and in the SRU period, four clusters involving nine of 29 (31%) infants were identified. It was possible to make an epidemiological link in all four SRU MDRO clusters, but this was not possible for the OBU cluster. In the latter case, transmission from an environmental source on the ward seemed likely. CONCLUSION: After transition to SRUs, there was no decrease in the number of clusters of MDROs with an epidemiological link, suggesting that nursing infants in an NICU with an SRU design is not, in itself, protective against the acquisition of MDROs.

Impact of transition from open bay to single room design neonatal intensive care unit on multidrug-resistant organism colonization rates.

BACKGROUND: The influence of the neonatal intensive care unit (NICU) design on the acquisition of multidrug-resistant organisms (MDROs) has not been well-documented. AIM: To examine the effect of single room unit (SRU) versus open bay unit (OBU) design on the incidence of colonization with MDROs and third-generation cephalosporin-resistant bacteria (3G-CRB) in infants admitted to the NICU. METHODS: Retrospective cohort study, including all infants admitted to the NICU of a tertiary care academic hospital two years prior to and two years following the transition from OBU to SRU in May 2017. Weekly cultures of throat and rectum were collected to screen for MDRO carriership. Incidence of colonization (percentage of all infants and incidence density per 1000 patient-days) with MDROs and 3G-CRB were compared between OBU and SRU periods. FINDINGS: Incidence analysis of 1293 NICU infants, identified 3.2% MDRO carriers (2.5% OBU, 4.0% SRU, not significant), including 2.3% extended-spectrum ß-lactamase-producing Enterobacterales carriers, and 18.6% 3G-CRB carriers (17% OBU, 20% SRU, not significant). No differences were found in MDRO incidence density per 1000 patient-days between infants admitted to OBU (1.56) compared to SRU infants (2.63). CONCLUSION: Transition in NICU design from open bay to SRUs was not associated with a reduction in colonization rates with MDROs or 3G-CRB in our hospital. Further research on preventing the acquisition and spread of resistant bacteria at high-risk departments such as the NICU, as well as optimal ward design, are needed.

[Two-year follow-up of infants born at 24 weeks gestation; first outcomes following implementation of the new 'Guideline for perinatal policy in cases of extreme prematurity']. / Follow-up na 2 jaar van kinderen geboren bij 24 weken.

OBJECTIVE: Since 2010 the guideline 'Guideline for perinatal policy in cases of extreme prematurity' has advised an active policy in infants born at 24 weeks gestation. We investigated how infants born at 24 and 25 weeks gestation in the first year following the implementation of the guideline had developed by the age of 2 years. DESIGN: Retrospective national cohort study. METHOD: The study population consisted of all surviving infants born in the Netherlands at 24 or 25 weeks gestation in the period from 1 October 2010 to 1 October 2011. At a corrected age of 2 years the children underwent a general physical and neurological examination, and their cognitive scores were determined on the 'Bayley scales of infant and toddler development' (Bayley III). Examinations took place in the 10 neonatal intensive care units (NICU's) in the Netherlands. RESULTS: Of 185 extremely premature infants, 166 were admitted to a NICU. A total of 95 survived to a corrected age of 2 years; 78 (82%) children were examined. Their average cognitive score on the Bayley III scale was 88 (SD: 16). Among the children born at 24 weeks gestation, 20% had mild disabilities and 20% had moderate to severe disabilities. Among the children born at 25 weeks gestation, 17% had mild disabilities and 12% had moderate to severe disabilities. CONCLUSION: Of the children born at 24 weeks gestation in the first year after the introduction of active policy in the Netherlands and surviving to 2 years of age (46%), more than half had developed without disabilities. This was comparable to children born at 25 weeks gestation. Of all children born at 24 weeks gestation, 25% survived to 2 years of age without disabilities.

Methodological aspects of 99mTc-sestamibi guided biopsy in breast cancer.

PURPOSE: This review aims to discuss the methodological aspects of dedicated molecular breast imaging (MBI) using 99mTc-sestamibi as radiotracer to guide biopsy of occult or unclear breast lesions on mammography (MG) and ultrasound (US) that are suspicious on MBI (BI-RADS criteria 4 and 5), including its advantages, limitations and future clinical applications. METHODS: Literature search was performed using the PubMed/MEDLINE database and "99mTc-sestamibi", "biopsy" and "breast cancer" as keywords. The search was restricted to English language. RESULTS: There are few studies on 99mTc-sestamibi guided biopsy methods; to our knowledge, no full studies have yet been reported on clinical validation of this new biopsy procedure. This review describes technical aspects of 99mTc-sestamibi guided biopsy and discusses the advantages and limitations of this procedure in comparison with MG, US and MRI-guided biopsy. CONCLUSIONS: MBI-guided biopsy appears to be a complementary modality and is principally indicated in the case of occult or unclear breast lesions on MG/US, that are suspicious on MBI. The future indication is in targeted biopsies in patients with large heterogeneous tumours. Further studies are needed to define the accuracy of this biopsy procedure.

Biochemical characterization of highly purified cytochrome P-450 and other components of the mixed function oxidase system of liver microsomal membranes.

Cytochrome P-450 has been purified from liver microsomes of phenobarbital-induced rabbits in the presence of ionic and nonionic detergents to concentrations over 17 nmoles per mg of protein. The purified cytochrome P-450 LM gives a single major band on SDS-polyacrylamide gel electrophoresis representing about 90 per cent of the total protein. The polypeptide chain has a molecular weight of about 49,000 daltons. NADPH-cytochrome P-450 reductase has been purified from liver microsomes of phenobarbital-induced rats in the presence of ionic and nonionic detergents to a stage where it catalyzes the reduction of 33,000 nmoles of cytochrome c per min per mg of protein. The ratio of activities toward cytochrome P-450 and cytochrome c is constant throughout purification. The purified reductase contains equimolar amounts of FMN and FAD and gives a single major band on SDA-polyacrylamide gel electrophoresis accounting for about 70 per cent of the total protein; the molecular weight is about 80,000 daltons. The purified cytochrome P-450 is free of cytochrome b5 but contains another electron acceptor, provisionally called Factor C, which is equivalent in amount to the heme present. Two electrons are taken up per molecule of cytochrome P-450 from dithionite or from NADPH in the presence of catalytic amounts of the reductase, and both electrons are readily transferred from the reduced cytochrome P-450 to molecular oxygen or artificial electron acceptors. The reconstituted enzyme system containing purified cytochrome P-450, purified NADPH-cytochrome P-450 reductase, and phosphatidylcholine retains the ability to catalyze the hydroxylation of drugs, fatty acids, hydrocarbons, and aniline in the presence of NADPH and molecular oxygen.