Detection of SARS-CoV-2 in dialysis effluent on a peritoneal dialysis program in mexico city: four cases

ABSTRACT

Introduction: Since the rapid spread of the COVID 19 pandemic, it is crucial to identify possible sources of transmission of the SARS-COV-2 virus in order to perform procedures safely. There has been interest to identify the presence of SARS-CoV-2 in different compartments including peritoneal compartment. SARS-CoV-2 was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) in dialysis effluent on a few single cases while other authors have reported negative results. Peritoneal membrane pores have a diameter of 20-40 nm while the SARS-CoV-2 virion diameter is between 60 to 140 nm, theoretically the virion could reach the peritoneal cavity by hematogenous diffusion or through the dialysis catheter after contact contamination. Case Description We report dialysis effluent findings of four patients, two women and two men, with an age range of 35 to 64 years and different comorbidities including diabetes mellitus, hypertension and obesity. They were diagnosed with COVID-19 using RT-PCR assay on nasopharyngeal samples or by tomography findings. RT-PCR samples of peritoneal effluent were obtained with a length of stay on peritoneal cavity of 6 hours, without centrifugation of the sample. Three patients were positive for presence of SARSCoV-2 on nasopharyngeal sample and dialysis effluent, while the fourth patient was negative in both samples despite having tomography findings suggestive of COVID-19 infection. It should be noted that in the 3 patients that had a positive RT-PCR on both nasopharyngeal and peritoneal effluent, samples were obtained within the first 7 days following the onset of symptoms associated with COVID-19 and on the fourth patient the peritoneal effluent sample was obtained 12 days after initial symptoms. All patients presented with acellular peritoneal fluid. No abdominal symptoms were reported. Discussion: Presence of SARS-CoV-2 on peritoneal fluid continues to be a subject of debate. Peritoneal effluent sample-drawing procedure has not been standardized, which may explain the inconsistent results noted by different authors. The positive results of the RT-PCR for SARS-CoV2 on peritoneal effluent must be confirmed on a larger sample. Although based on a small group, these findings should prompt to consider these fluids as potentially infective.