PATIENTS AND METHODS: Patients were part of a prospective multicentre observational study recruiting people with bladder cancer for a urine biomarker study (DETECT II; ClinicalTrials.gov: NCT02781428). A mixed-methods approach comprising (1) a questionnaire to assess patients' experience with cystoscopy and patients' preference for cystoscopy vs urinary biomarker, and (2) semi-structured interviews to understand patient views, choice and reasons for their preference.
RESULTS: A urine biomarker with an MAS of 90% would be accepted by 75.8% of patients. This was despite a high self-reported prevalence of haematuria (51.0%), dysuria/lower urinary tract symptoms (69.1%) and urinary tract infection requiring antibiotics (25.8%). There was no association between MAS with patient demographics, adverse events experienced, cancer characteristics or distance of patients' home to hospital. The qualitative analysis suggested that patients acknowledge that cystoscopy is invasive, embarrassing and associated with adverse events but are willing to tolerate the procedure because of its high sensitivity. Patients have confidence in cystoscopy and appreciate the visual diagnosis of cancer. Both low- and high-risk patients would consider a biomarker with a reported sensitivity similar to that of cystoscopy.
CONCLUSION: Patients value the high sensitivity of cystoscopy despite the reported discomfort and adverse events experienced after it. The sensitivity of a urinary biomarker must be close to cystoscopy to gain patients' acceptance.
METHODS: Plasma and serum samples were collected from adults participating in four independent studies at different time points, ranging from several days up to 14 months post-SARS-CoV-2 infection. The primary outcome measure was to quantify SARS-CoV-2 antigens, including the S1 subunit of spike, full-length spike, and nucleocapsid, in participant samples. The presence of 34 commonly reported PASC symptoms during the postacute period was determined from participant surveys or chart reviews of electronic health records.
RESULTS: Of the 1569 samples analysed from 706 individuals infected with SARS-CoV-2, 21% (95% CI, 18-24%) were positive for either S1, spike, or nucleocapsid. Spike was predominantly detected, and the highest proportion of samples was spike positive (20%; 95% CI, 18-22%) between 4 and 7 months postinfection. In total, 578 participants (82%) reported at least one of the 34 PASC symptoms included in our analysis ≥1 month postinfection. Cardiopulmonary, musculoskeletal, and neurologic symptoms had the highest reported prevalence in over half of all participants, and among those participants, 43% (95% CI, 40-45%) on average were antigen-positive. Among the participants who reported no ongoing symptoms (128, 18%), antigen was detected in 28 participants (21%). The presence of antigen was associated with the presence of one or more PASC symptoms, adjusting for sex, age, time postinfection, and cohort (OR, 1.8; 95% CI, 1.4-2.2).
DISCUSSION: The findings of this multicohort study indicate that SARS-CoV-2 antigens can be detected in the blood of a substantial proportion of individuals up to 14 months after infection. While approximately one in five asymptomatic individuals was antigen-positive, roughly half of all individuals reporting ongoing cardiopulmonary, musculoskeletal, and neurologic symptoms were antigen-positive.