Analysis of two sequential SARS-CoV-2 outbreaks on a haematology-oncology ward and the role of infection prevention.

Two SARS-CoV-2 nosocomial outbreaks occurred on the haematology ward of our hospital. Patients on the ward were at high risk for severe infection because of their immunocompromised status. Whole Genome Sequencing proved transmission of a particular SARS-CoV-2 variant in each outbreak. The first outbreak (20 patients/31 healthcare workers (HCW)) occurred in November 2020 and was caused by a variant belonging to lineage B.1.221. At that time, there were still uncertainties on mode of transmission of SARS-CoV-2, and vaccines nor therapy were available. Despite HCW wearing II-R masks in all patient contacts and FFP-2 masks during aerosol generating procedures (AGP), the outbreak continued. Therefore, extra measures were introduced. Firstly, regular PCR-screening of asymptomatic patients and HCW; positive patients were isolated and positive HCW were excluded from work as a rule and they were only allowed to resume their work if a follow-up PCR CT-value was ≥30 and were asymptomatic or having only mild symptoms. Secondly, the use of FFP-2 masks was expanded to some long-lasting, close-contact, non-AGPs. After implementing these measures, the incidence of new cases declined gradually. Thirty-seven percent of patients died due to COVID-19. The second outbreak (10 patients/2 HCW) was caused by the highly transmissible omicron BA.1 variant and occurred in February 2022, where transmission occurred on shared rooms despite the extra infection control measures. It was controlled much faster, and the clinical impact was low as the majority of patients was vaccinated; no patients died and symptoms were relatively mild in both patients and HCW.

Despite Excellent Test Characteristics of the cobas 4800 CT/NG Assay, Detection of Oropharyngeal Chlamydia trachomatis and Neisseria gonorrhoeae Remains Challenging.

Oropharyngeal Chlamydia trachomatis (CT) infections and, especially, Neisseria gonorrhoeae (NG) infections are common, but few commercial nucleic acid amplification tests (NAATs) specify extragenital samples for intended use. The test characteristics of the cobas 4800 CT/NG assay were evaluated for oropharyngeal swabs. The technical validation included analysis of the specificity, sensitivity, dynamic range, linearity, efficiency, and precision. The probability of detection curve combined with historical data enabled the estimation of potentially missed diagnoses. A clinical evaluation was performed on a subset of 2,798 clinical samples available from routine diagnostics. Results of the cobas 4800 were compared with those from in-house C. trachomatis/N. gonorrhoeae PCR assays. Discrepant samples were tested with resolver assays, and these results were considered decisive. No cross-reactivity was seen in the analytical specificity analysis. High linearity (R2 ≥ 0.983), efficiency (89% to 99%), and precision (cycle threshold [CT ] value of 0.1 to 0.9) were seen for both C. trachomatis and N. gonorrhoeae The limit of detection in oropharyngeal samples was 3.2 × 102 inclusion-forming units (IFU)/ml for C. trachomatis and 6.7 × 102 CFU/ml for N. gonorrhoeae Estimates on potentially missed diagnoses were up to 7.2% for C. trachomatis and up to 24.7% for N. gonorrhoeae Clinical sensitivity and specificity were evaluated with 25 C. trachomatis-positive, 86 N. gonorrhoeae-positive, and 264 negative samples, resulting in 100% and 99.6% for C. trachomatis and 100% and 96.7% for N. gonorrhoeae, respectively. The findings in this study demonstrate the utility of the cobas 4800 CT/NG assay for oropharyngeal samples. Despite its being a highly accurate test, the range of reported CT values, especially for N. gonorrhoeae, suggests relatively low oropharyngeal loads. Hence, consistent detection over the full range of oropharyngeal loads could be impaired.

Safety and effects of two red blood cell transfusion strategies in pediatric cardiac surgery patients: a randomized controlled trial.

OBJECTIVE: To investigate the safety and effects of a restrictive red blood cell (RBC) transfusion strategy in pediatric cardiac surgery patients. DESIGN: Randomized controlled trial. SETTING: Pediatric ICU in an academic tertiary care center, Leiden University Medical Center, Leiden, The Netherlands. PATIENTS: One hundred seven patients with non-cyanotic congenital heart defects between 6 weeks and 6 years of age. One hundred three patients underwent corrective surgery on cardiopulmonary bypass. INTERVENTIONS: Prior to surgery patients were randomly assigned to one of two groups with specific RBC transfusion thresholds: Hb 10.8 g/dl (6.8 mmol/l) and Hb 8.0 g/dl (5.0 mmol/l). MEASUREMENTS: Length of stay in hospital (primary outcome), length of stay in PICU, duration of ventilation (secondary outcome), incidence of adverse events and complications related to randomization (intention to treat analysis). RESULTS: In the restrictive transfusion group, mean volume of transfused RBC was 186 (±70) ml per patient and in the liberal transfusion group 258 (±87) ml per patient, (95% CI 40.6-104.6), p < 0.001. Length of hospital stay was shorter in patients with a restrictive RBC transfusion strategy: median 8 (IQR 7-11) vs. 9 (IQR 7-14) days, p = 0.047. All other outcome measures and incidence of adverse effects were equal in both RBC transfusion groups. Cost of blood products for the liberal transfusion group was 438.35 (±203.39) vs. 316.27 (±189.96) euros (95% CI 46.61-197.51) per patient in the restrictive transfusion group, p = 0.002. CONCLUSIONS: For patients with a non-cyanotic congenital heart defect undergoing elective cardiac surgery, a restrictive RBC transfusion policy (threshold of Hb 8.0 g/dl) during the entire perioperative period is safe, leads to a shorter hospital stay and is less expensive.

Dissemination of Bacillus cereus in a paediatric intensive care unit traced to insufficient disinfection of reusable ventilator air-flow sensors.

Over a two-week period in November 2006, vancomycin-resistant Bacillus cereus was isolated from respiratory samples from six ventilated paediatric intensive care unit (PICU) patients. To investigate the possibility of a common source and extent of the dissemination, all procedures related to mechanical ventilation were monitored and surveillance cultures performed. B. cereus was isolated from reusable air-flow sensors, before and after on-site disinfection with 70% alcohol. The organism was also isolated from respiratory samples from three other ventilated patients and from two ventilation grids in the ceiling of PICU, as well as from the alcohol solution itself. Using amplified fragment length polymorphism (AFLP) typing, B. cereus strains from the six PICU patients together with isolates recovered from the air-flow sensors and the alcohol solution were shown to be closely related. Isolates from the ventilation grids demonstrated different AFLP patterns to the outbreak strain. Intervening measures, including disinfection by autoclaving all reusable air-flow-guiding parts and the use of disposable non-autoclavable parts, resulted in rapid termination of the outbreak. B. cereus infections can cause significant morbidity, particularly in intensive care patients. Disinfection of all air-flow-guiding reusable parts for mechanical ventilation should be addressed with great care and should include effective autoclaving in order to eradicate spores.

Swine-like hepatitis E viruses are a cause of unexplained hepatitis in the Netherlands.

Hepatitis E virus (HEV) infections in developed countries are recognized as an imported disease related to travel to endemic regions. However, increasing evidence suggests that HEV infection may also occur in the developed countries and that swine may act as a possible reservoir. To investigate the indigenous transmission of HEV in the Netherlands, sera from 50 blood donors and 1027 sera from patients with acute hepatitis were screened with an ELISA for HEV-specific IgG and IgM. Because the Netherlands is considered a nonendemic region, all positive ELISA results were confirmed by immunoblot to exclude false-positive results. Evidence of recent HEV infection was detected in 0% of the blood donors and 4.4% of the cases, based on combined positive IgM and IgG responses. The serodiagnosis was confirmed by a positive polymerase chain reaction (PCR) in 24 patients with hepatitis (2.3% overall, 51% of confirmed IgM+/IgG+ cases). IgG antibodies alone were detected in 4.2% of patients. We found related sequences to virus strains detected in Dutch pigs (genotype 3, 91-97% homology) in 89% of PCR-confirmed HEV patients. The detection of unique swine-like HEV sequences in 16 indigenous hepatitis patients without a recent travel history suggests that HEV is endemic in the Netherlands. We recommend including HEV tests in unexplained acute hepatitis patients, despite their travel history.

On the uptake and release of zinc (65Zn) in the growing alga Selenastrum capricornutum Printz.

A Zn- and pH-buffered medium was used to study the accumulation of Zn in batch-cultured algae (Selenastrum capricornutum Printz.). All experiments were carried out using (65)Zn radiotracers, which were measured by gamma-ray spectrometry. Zinc was applied in the presence of nitrilotriacetic acid (NTA), leading to free Zn(2+) concentrations ranging from 4.2 x 10(-11) to 1.6 x 10(-7) mol litre(-1). During the 75-h experiments, the rates of Zn influx and efflux were determined, the latter with full consideration for algal growth rates. Algal growth stopped completely at a free Zn(2+) concentration of 1.6 x 10(-8) mol litre(-1). Initial Zn binding was determined and, based on free Zn(2+) concentrations, presented by the apparent dissociation constant K(diss) and capacity C as 4.6 x 10(-9) mol litre(-1) and 19.8 x 10(6) mol gDW(-1), respectively. The rate constant of Zn efflux could be calculated as a constant 0.021 +/- 0.003 h(-1), irrespective of the Zn concentrations applied. The rates of Zn influx were expressed by the V(max) and K(M) values as 3.3 x 10(-10) mol gDW(-1) s(-1) and 6.3 x 10(-9) mol litre(-1), respectively. These values, which are based on applied free Zn(2+) concentrations, are compatible with the operation of a high-affinity low-concentration carrier mechanism. The results suggest that, under the conditions applied, free Zn(2+) may be the most relevant Zn species for Zn uptake; furthermore, relative growth rate may be regarded as a relatively sensitive signal for Zn stress circumstances.

[Nitric oxide to combat pulmonary hypertension in an infant following heart surgery for septum defect]. / Stikstofmonoxyde ter bestrijding van pulmonale hypertensie bij een zuigeling na cardiochirurgie wegens septumdefect.

A 5-month-old female infant with Down syndrome underwent surgical repair of a complete atrioventricular septal defect and a patent ductus arteriosus. The postoperative course was complicated by life-threatening pulmonary hypertensive crises which did not respond to conventional vasodilating therapy. Nitric oxide inhalation resulted in rapid decrease in pulmonary artery pressure and improvement of haemodynamics and oxygenation without causing any untoward side effects. Inhalation of NO was continued over the next 4 days, with a maximum NO concentration of 20 ppm during a period of 12 hours. The subsequent postoperative course was uneventful and the patient was discharged from the hospital in good health on the 23rd postoperative day.

Efficacy of epidurally administered sufentanil versus bupivacaine during thoracic surgery. A randomised placebo-controlled double-blind study.

The efficacy of thoracic epidural sufentanil 50 micrograms was compared with bupivacaine 0.5% with adrenaline 5 micrograms.ml-1 (dose 40 mg) or saline, in 30 patients (n = 10 in each group) undergoing lateral thoracotomy. Sufentanil, bupivacaine or saline was administered epidurally after induction of anaesthesia with sufentanil 1 microgram.kg-1 and thiopentone 2-5 mg.kg-1. Anaesthesia was maintained with nitrous oxide 66% and halothane 0.3%. Supplementary sufentanil 25 micrograms was given whenever the systolic arterial blood pressure increased more than 15 mmHg above the pre-operative value, whenever heart rate exceeded 90 beat.min-1 in the absence of hypovolaemia, or when other autonomic or somatic signs occurred. Fewer patients in the epidural sufentanil (n = 4, p < 0.005) and bupivacaine (n = 1, p < 0.001) groups required supplementary sufentanil compared to the placebo group, in which all patients needed supplementary sufentanil, but there was no statistical difference between the sufentanil and bupivacaine groups. One or more hypotensive episodes occurred in five patients in the sufentanil group, in all patients in the bupivacaine group and in no patient in the placebo group, and the differences were significant (p < 0.02).

Influence of Crohn's disease on the pharmacokinetics and pharmacodynamics of alfentanil.

We have compared the dose requirements, pharmacokinetics and pharmacodynamics of alfentanil in 12 patients with Crohn's disease and 10 control patients undergoing abdominal surgery. Plasma concentrations of alpha 1-acid glycoprotein (AAG) and alfentanil protein binding were also measured. Anaesthesia was induced with alfentanil 100 micrograms kg-1 and thiopentone, and maintained with nitrous oxide in oxygen and alfentanil 25-200 micrograms kg-1 h-1. Arterial blood samples were obtained before and after each change in the alfentanil infusion rate and for 6 h after stopping the infusion. Pharmacokinetic data were derived using non-compartmental methods. Alfentanil concentration-effect data were evaluated by non-linear regression, where effect was either response or no response to surgical stimulation. Mean intraoperative alfentanil requirement was greater in patients with Crohn's disease (2.48 micrograms kg-1 min-1) than in control patients (1.35 micrograms kg-1 min-1) (P < 0.01). Mean elimination half-life, total plasma clearance and steady state distribution volume in patients with Crohn's disease were comparable to those in control patients (80 vs 81 min, 5.7 vs 6.4 ml kg-1 min-1 and 0.70 vs 0.68 litre kg-1, respectively). Mean plasma concentration at which the probability of no response was 50% for the intra-abdominal period of surgery was greater in the Crohn group (359 ng ml-1) than in the control group (199 ng ml-1) (P < 0.02). Plasma AAG concentrations were greater in the Crohn group, but the free fraction of alfentanil was similar in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Alfentanil requirement in Crohn's disease. Increased alfentanil dose requirement in patients with Crohn's disease.

The dose requirement of alfentanil as a supplement to nitrous oxide anaesthesia was studied in 13 patients with Crohn's disease and seven control patients all of whom underwent laparotomy. Alfentanil was administered as a variable rate infusion with supplemental bolus injections titrated to the patient's needs. The alfentanil requirement was independent of the duration of surgery and was significantly higher in patients with Crohn's disease than in control patients. The results indicate that Crohn's disease alters the dose requirement of alfentanil.