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A 69-year-old male patient who developed a fever up to 37.7°C with dry cough, no sputum, and no other symptoms on 22 January 2020. On 23 January 2020, he was hospitalized. Physical examination: temperature 37.7°C, heart rate 87 bpm, breathing rate 20 bpm, blood pressure 150/102 mmHg. The patient’s general condition was fair, with clear breathing sounds of both lungs, no rales, and no positive signs of the heart.
Accessory examination: blood routine: WBC 3.1 × 109/L, Lym 1.0 × 109/L, CRP 3.1 mg/L, IL-6 4.43 pg/ml. Arterial blood gas analysis: pH 7.38, PaCO2 44 mmHg, PaO2 102 mmHg, PaO2/FiO2 486; lung CT: patchy ground-glass opacity in the left upper lobe.
On 24 January, confirmed CoVID-19 diagnosis with the positive SARS-CoV-2 RT-PCR test result on sputum samples.
After admission, he received antiviral treatments(interferon-alpha inhalation, lopinavir/ritonavir), without antibiotics or glucocorticoids.
On 25 January, the patient’s body temperature returned to normal, and there was no cough and no other discomfort.
On 29 January, the repeated lung CT showed improved ground-glass opacity in the left upper lobe but new patchy opacity in the right lower lobe. On 12 February, lung CT showed substantially improved lesions. On 11 February and 13 February, SARS-CoV-2 nucleic acid test (Throat swabs) were negative, and the sputum sample was negative on 13 February.
On 15 February, the patient met the discharge criteria for CoVID-19 and was discharged, followed by further self-isolation and observation.
On 29 February, the patient returned to the hospital for a follow-up visit, and his sputum sample was positive for SARS-CoV-2 nucleic acid; the patient presented no subjective symptoms, no positive signs, and generally improved lesions in both lungs on the CT scan.
How to explain the retested positive Viral RNA result after 2 weeks hospital discharge? Does this indicate a relapse or intermittent virus shedding?