You are presented with a paragraph from a COVID-19 literature. Classify the topics of this piece of text by choosing from the following categories:

- Epidemic Forecasting: The content relates to predictions about the spread of COVID-19.
- Treatment: The paragraph discusses therapeutic methods or medication for COVID-19.
- Prevention: The content covers measures to prevent the spread of COVID-19.
- Mechanism: The paragraph explains the biological mechanisms of the virus.
- Case Report: The content is a report of a COVID-19 case.
- Transmission: The paragraph discusses how COVID-19 is transmitted.
- Diagnosis: The content is about diagnosing COVID-19 in individuals.

Your classification should be provided as an element within a JSON array. The array should be formatted with topics enclosed in double quotes and separated by commas, following the JSON format, for example: ["Topic1", "Topic2", ...]. Include all applicable topics within the array. Your output should be a valid JSON array, and no additional text should be included in your response.

Article:

BACKGROUND: Our objective was to the describe indications, management, complications and outcomes of renal replacement therapy (RRT) in COVID-19 critically ill patients. To contextualise these findings, comparisons were made against 36 non-COVID-19 consecutive patients requiring RRT on ICU. METHODS: We conducted a retrospective single centre observational cohort study of patients requiring acute RRT between 1st March and 30th June 2020. Comparison was made against those receiving RRT in the pre-COVID-19 period from January 2019 to February 2020. RESULTS: Of 154 COVID-19 patients, 47 (30.5%) received continuous venovenous haemofiltration (CVVHF), all of whom required mechanical ventilation and vasopressor support. The requirement for RRT was related to fluid balance rather than azotaemia. Compared to 36 non-COVID-19 patients, those with COVID-19 were younger (p=0.016) with a lower serum creatinine on hospital admission (p=0.049), and lesser degrees of metabolic acidosis (p<0.001) and lactataemia (p<0.001) before initiation of RRT. In addition, the duration of RRT requirement was longer (p<0.001). Despite lower CVVHF exchange rates with higher serum creatinine levels following RRT initiation in the COVID-19 patients, metabolic abnormalities were corrected. Hospital mortality was 60% among COVID-19 patients requiring RRT, compared to 67% in non-COVID patients (p=0.508), and renal recovery among survivors without pre-existing CKD was similar (p=0.231). CONCLUSIONS: The requirement for RRT in COVID-19 patients was primarily related to fluid balance and using lower CVVHF exchange rates was effective to correct metabolic abnormalities. Renal recovery occurred in all but one patient by 60 days in the 40% of patients who survived.
["Diagnosis", "Treatment"]