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:

A 67-year-old male diabetic patient with systemic arterial hypertension was admitted to the emergency department with a necrotic ulcer in the left external malleolus and no palpable popliteal or pedal pulses. Arterial Duplex ultrasound identified femoropopliteal occlusion, with popliteal refilling below the knee and a patent peroneal artery. An endovascular procedure was performed, requiring retrograde access to the popliteal artery to re-establish blood flow and deploy a popliteal stent. Technical success was achieved and the patient underwent debridement of the wound. Two days later, about 48 hours after the operation, the patient began to exhibit respiratory symptoms, with coughing and dyspnea. He immediately underwent a chest CT that identified ground glass opacities, the crazy-paving pattern, and bilateral air bronchogram in the lungs. A reverse transcription - polymerase chain reaction (RT-PCR) test was positive for SARS-Cov-2. The patient was moved to an intensive care unit and put on mechanical ventilation. Both hydroxychloroquine and azithromycin were administered. Despite appropriate treatment, the patient died 4 days after he was diagnosed with COVID-19.
["Case Report"]