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Clinical Features of Asymptomatic SARS-CoV-2 Infection in Hemodialysis Patients
Maria Soledad Pizarro-Sánchez1, Alejandro Avello2, Sebastian Mas-Fontao3
1Nephrology and Hypertension, Rey Juan Carlos Hospital, Madrid, Spain.
Insights
Asymptomatic COVID-19 is common in hemodialysis patients, particularly those who initially test negative but later develop antibodies. This suggests actual mortality rates for COVID-19 in this population may be lower than previously thought.
Area of Science:
- Nephrology
- Infectious Diseases
- Critical Care Medicine
Background:
- Chronic kidney disease (CKD) is a known risk factor for severe COVID-19.
- The clinical presentation of COVID-19 in hemodialysis patients remains incompletely understood.
Purpose of the Study:
- To characterize the clinical spectrum of COVID-19 in patients undergoing hemodialysis.
Main Methods:
- A retrospective observational study included 66 hemodialysis patients.
- Methods involved nasopharyngeal swab PCR, SARS-CoV-2 serology, blood tests, chest radiography, and outcome assessment.
Main Results:
- 50 patients were diagnosed with COVID-19 (38 PCR-positive, 12 PCR-negative with seroconversion).
- Asymptomatic infection was more frequent in PCR-negative patients (58%) compared to PCR-positive patients (13%).
- Overall mortality was 14%, occurring exclusively in symptomatic PCR-positive patients.
Conclusions:
- Asymptomatic SARS-CoV-2 infection is prevalent in hemodialysis patients, especially those with delayed seroconversion.
- COVID-19 mortality in hemodialysis patients may be underestimated when relying solely on PCR testing.
Background:
CKD is a risk factor for severe COVID-19. However, the clinical spectrum of COVID-19 in hemodialysis patients is still poorly characterized.
Objective:
To analyze the clinical spectrum of COVID-19 on hemodialysis patients.
Method:
A retrospective observational study was conducted on 66 hemodialysis patients. Nasopharyngeal swab PCR and serology for SARS-CoV-2, blood analysis, chest radiography, treatment, and outcomes were assessed.
Results:
COVID-19 was diagnosed in 50 patients: 38 (76%) were PCR-positive and 12 (24%) were PCR-negative but developed anti-SARS-CoV-2 antibodies. By contrast, 17% of PCR-positive patients failed to develop detectable antibodies against SARS-CoV-2. Among PCR-positive patients, 5/38 (13%) were asymptomatic, while among PCR-negative patients 7/12 (58%) were asymptomatic (p = 0.005) for a total of 12/50 (24%) asymptomatic patients. No other differences were found between PCR-positive and PCR-negative patients. No differences in potential predisposing factors were found between asymptomatic and symptomatic patients except for a lower use of ACE inhibitors among asymptomatic patients. Asymptomatic patients had laboratory evidence of milder disease such as higher lymphocyte counts and oxygen saturation and lower troponin I and interleukin-6 levels than symptomatic patients. Overall mortality was 7/50 (14%) and occurred only in symptomatic PCR-positive patients in whom mortality was 7/33 (21%).
Conclusions:
Asymptomatic SARS-CoV-2 infection is common in hemodialysis patients, especially among patients with initial negative PCR that later seroconvert. Thus COVID-19 mortality in hemodialysis patients may be lower than previously estimated based on PCR tests alone.
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