Prognostic Factors of Peritonitis in Patients on Peritoneal Dialysis: a Retrospective Observational Study.

Background/Objectives. Peritoneal dialysis stands as an established form of renal replacement therapy; yet peritonitis remains a major complication associated with it. This study, analyzing two decades of data from the Nephrology, Dialysis, and Hypertension Division of the University-Hospital IRCCS in Bologna, aimed to identify prognostic factors linked to peritonitis events. It also sought to evaluate the suitability of different peritoneal dialysis techniques, with a focus on Automated Peritoneal Dialysis (APD) and Continuous Ambulatory Peritoneal Dialysis (CAPD). Additionally, the study assessed the impact of an educational program introduced in 2005 on peritonitis frequency. Methods. Conducting an observational, retrospective, single-center study, 323 patients were included in the analysis, categorized based on their use of APD or CAPD. Results. Despite widespread APD usage, no significant correlation was found between the dialysis technique (APD or CAPD) and peritonitis onset. The analysis of the educational program's impact revealed no significant differences in peritonitis occurrence. However, a clear relationship emerged between regular patient monitoring at the reference center and the duration of peritoneal dialysis. Conclusions. Despite the absence of a distinct association between peritonitis onset and dialysis technique, regular patient monitoring at the reference center significantly correlated with prolonged peritoneal dialysis duration.

EFOMP's protocol quality controls in PET/CT and PET/MR.

This article presents the protocol on Quality Controls in PET/CT and PET/MRI published online in May 2022 by the European Federation of Organisations for Medical Physics (EFOMP), which was developed by the Working group for PET/CT and PET/MRI Quality Control (QC) protocol. The main objective of this protocol was to comprehensively provide simple and practical procedures that may be integrated into clinical practice to identify changes in the PET/CT/MRI system's performance and avoid short- and long-term quality deterioration. The protocol describes the quality control procedures on radionuclide calibrators, weighing scales, PET, CT and MRI systems using selected and measurable parameters that are directly linked to clinical images quality. It helps to detect problems before they can impact clinical studies in terms of safety, image quality, quantification accuracy and patient radiation dose. CT and MRI QCs are described only in the context of their use for PET (attenuation correction and anatomical localization) imaging. Detailed step-by-step instructions have been provided, limiting any misinterpretations or interpersonal variations as much as possible. This paper presents the main characteristics of the protocol illustrated together with a brief summary of the content of each chapter. A regular QC based on the proposed protocol would guarantee that PET/CT and PET/MRI systems operate under optimal conditions, resulting in the best performance for routine clinical tasks.

[The COVID-19 emergency management in Nephrology: a cross-sectional survey on the procedures management to deal with the pandemic].

From mid-March 2020, the pandemic caused by COVID 19 has placed health facilities in front of the need to implement a rapid and profound reorganization. However, many hospitals have not had time to organize a rapid and effective response, both for the speed of spread of the virus, and for the lack of previous experience with a pandemic of this magnitude. With the aim of assessing the knowledge and adoption of the procedures and recommendations disseminated by hospitals during the COVID-19 pandemic, in the dialysis and hemodialysis services of Italian centers, a cross-sectional survey was designed by the Society of Nurses in Nephrology (SIAN). The online survey was conducted among nurses who work in the Italian services of dialysis and hemodialysis during the first and second waves. The online survey was completed by 150 nurses. Although hospitals have set up protocols and procedures for patient management during the COVID-19 pandemic, among participants not all were aware of it. With regard to the training of personnel in the use of personal protective equipment, 18.6% declared that they have not received it. The majority implemented specific precautions for patient management, awareness and information.

[SARS-CoV-2: recommendations on nursing care for dialyzed and transplanted patient].

Coronavirus disease 2019 is an infectious respiratory syndrome caused by the virus called SARS-CoV-2, belonging to the family of coronaviruses. The first ever cases were detected during the 2019-2020 pandemic. Coronaviruses can cause a common cold or more serious diseases such as Middle Eastern Respiratory Syndromes (MERS) and Severe Acute Respiratory Syndrome (SARS). They can cause respiratory, lung and gastrointestinal infections with a mild to severe course, sometimes causing the death of the infected person. This new strain has no previous identifiers and its epidemic potential is strongly associated with the absence of immune response/reactivity and immunological memory in the world population, which has never been in contact with this strain before. Most at risk are the elderly, people with pre-existing diseases and/or immunodepressed, dialyzed and transplanted patients, pregnant women, people with debilitating chronic diseases. They are advised to avoid contacts with other people, unless strictly necessary, and to stay away from crowded places, also observing scrupulously the recommendations of the Istituto Superiore di Sanità. In this article we detail the recommendations that must be followed by the nursing care staff when dealing with chronic kidney disease patients in dialysis or with kidney transplant patients. We delve into the procedures that are absolutely essential in this context: social distancing of at least one meter, use of PPI, proper dressing and undressing procedures, frequent hand washing and use of gloves, and finally the increase of dedicated and appropriately trained health personnel on ward.

(90)Y-PET/CT Imaging Quantification for Dosimetry in Peptide Receptor Radionuclide Therapy: Analysis and Corrections of the Impairing Factors.

PURPOSE: We evaluated the possibility to assess (90)Y-PET/CT imaging quantification for dosimetry in (90)Y-peptide receptor radionuclide therapy. METHODS: Tests were performed by Discovery 710 Elite (GE) PET/CT equipment. A body-phantom containing radioactive-coplanar-spheres was filled with (90)Y water solution to reproduce different signal-to-background-activity-ratios (S/N). We studied minimum detectable activity (MDA) concentration, contrast-to-noise ratio (CNR), and full-width-at-half-maximum (FWHM). Subsequently, three recovery coefficients (RC)-based correction approaches were evaluated: maximum-RC, resolution-RC, and isovolume-RC. The analysis of the volume segmentation thresholding method was also assessed to derive a relationship between the true volume of the targets and the threshold to be applied to the PET images. (90)Y-PET/CT imaging quantification was then achieved on some patients and related with preclinical tests. Moreover, the dosimetric evaluation was obtained on the target regions. RESULTS: CNR value was greater than 5 if the MDA was greater than 0.2 MBq/mL with no background activity and 0.5-0.7 MBq/mL with S/N ranging from 3 to 6. FWHM was equal to 7 mm. An exponential fitting of isovolume RCs-based correction technique was adopted for activity quantification. Adaptive segmentation thresholding exponential curves were obtained and applied for target volume identification in three signal-to-background-activity-ratios. The imaging quantification study and dosimetric evaluations in clinical cases was feasible and the results were coherent with those obtained in preclinical tests. CONCLUSIONS: (90)Y-PET/CT imaging quantification is possible both in phantoms and in patients. Absorbed dose evaluations in clinical applications are strongly related to targets activity concentration.

Radiation dosimetry of 18F-fluorocholine PET/CT studies in prostate cancer patients.

PURPOSE: We aimed to evaluate the Equivalent Doses (HTs) to highly exposed organs as well as the Effective Dose (ED) for (18)F-fluorocholine PET/CT scan in the follow-up of prostate cancer patients. METHODS: Fifty patients were administered with (18)F-fluorocholine. The activities in organs with the highest uptake were derived by region-of-interest (ROI) analysis. OLINDA/EXM1.0 and Impact software were used to assess ED for the administered (18)F-fluorocholine and CT scan, respectively, and the (18)F-fluorocholine and CT-scan EDs summed to yield the total ED for the PET/CT procedure. RESULTS: The calculated (18)F-fluorocholine and CT scans EDs based on ICRP Publication 103 were 5.2 mSv/300 MBq and 6.7 mSv, respectively. The (18)F-fluorocholine HTs to the liver, kidneys, spleen and pancreas were about threefold higher than those from the CT, which contributed a greater proportion of the total ED than the (18)F-fluorocholine did. CONCLUSIONS: For (18)F-fluorocholine PET/CT procedures, about 40% of the ED is contributed by administered (18)F-fluorocholine and 60% by the CT scan. The kidneys and liver were the highly exposed organs. Considering the large number of diagnostic procedures oncology patients undergo, radiation dosimetry is important in relation to the stochastic risk of such procedures.

Quantitative analysis of 90Y Bremsstrahlung SPECT-CT images for application to 3D patient-specific dosimetry.

AIM: The aim of this study was to evaluate the accuracy of the activity quantification of single-photon emission computed tomography/computed tomography (SPECT-CT) (90)Y-Bremsstrahlung images and to validate the S-voxel method. METHODS: An anthropomorphic torso phantom with radioactive inserts ((90)Y) was acquired by SPECT-CT. Constant calibration factors (cps/MBq) for the quantification were evaluated, considering different volume, shape, position inside the phantom, activity concentration and background, and distance from detectors. S-voxel values (EGSnrc) were implemented in MATLAB R0086 USA software. Dose comparisons between S-voxel and the conventional Medical Internal Radiation Dose method were repeated in a group of 11 patients administered with (90)Y-DOTATATE. RESULTS: Using the appropriate calibration factors to recover the volume variability, the error about the measurement repeatability and the activity variation was within 4%. The variability of activity quantification, depending on the position in the phantom, detector distance, and background, was <10%, <5%, and <10%, respectively. The absorbed-dose values calculated by OLINDA were in agreement with the mean dose values obtained by the S-voxel method (difference, <10%). CONCLUSIONS: The results confirm that, with the hybrid SPECT-CT system, quantitative analysis of SPECT (90)Y-Bremsstrahlung images and the generation of three-dimensional dose distributions are feasible. The improved analysis of Bremsstrahlung images could have a notable clinical impact, allowing to address the dosimetric verification to patients during the course of therapy.