Background. The self-locating peritoneal dialysis (PD) catheter, contains a tungsten tip. The effects of magnetic resonance (MR) on the catheter were evaluated, emphasizing its MR signal, artifacts, ferromagnetism, and possible heating production during the MR sequences. Methods. The catheter was studied in an ex vivo model using a 1.5TMR system and placed into a plastic box containing saline solution. Acquisitions on coronal and axial planes were obtained on fast gradient-echo T1-weighted and fast spin-echo T2-weighted. In vivo abdominal MR exams were also carried out. Results. Overall, the catheter had good visibility. In all sequences, an extensive paramagnetic blooming artifact was detected at the level of the tip tungsten ballast, with a circular artifact of 5cm in diameter. The catheter showed no magnetic deflection, rotation, or movements during all MR sequences. After imaging, the temperature of the saline solution did not change compared to the basal measurement. Patients safely underwent abdominal MR. Conclusions. The results point to the possibility of safely performing MR in PD patients carrying the self-locating catheter. The self-locating PD catheter is stable when subjected to a 1.5TMR system. However, it creates some visual interference, preventing an accurate study of the tissues surrounding the tungsten tip.

Kidney transplant recipients are a vulnerable population at risk of a life-threatening COVID-19 infection with an incidence of death four-times higher than in the general population. The availability of mRNA COVID-19 vaccines has dramatically changed the fate of this infection also within this fragile population. Transplanted patients have an impaired immunological response also to mRNA vaccines. In March 2021, however, we started a vaccination campaign. These preliminary results show that both the incidence of death and of hospitalization dropped from 13% to 2.4% and from 45% to 12.5% compared to the previous outbreaks reported by our group. In univariate analysis, two variables were associated with an increased risk of hospitalization: older age and dyspnea (p = 0.023, p < 0.0001, respectively). In multivariate analysis, dyspnea (p < 0.0001) and mycophenolate therapy (p = 0.003) were independently associated with the risk of hospitalization. The association was even stronger when the two variables were combined (p < 0.0001). Vaccinations did not reduce the incidence of COVID-19 infections among our transplanted patients, but provided certain protection that was associated with a significantly better outcome for this infection.