Dr Pham Khac Tuong
Vice Dean of Respiratory Department
Xuyen A Hospital
Ho Chi Minh City, Vietnam

Classification of COVID-19 is based on disease severity, with moderate disease associated with pneumonia, while severe cases involve respiratory complications and presence of pre-disposing factors linked to advanced age, cardiovascular disease, diabetes, chronic respiratory disease, and cancer.¹ Although the majority of patients experience mild symptoms that may be managed by close monitoring and supportive care, patients with COVID-linked pneumonia require appropriate treatment, and/or hospitalisation in more severe cases.^1,2 Predicting disease course and severity is an ongoing challenge, especially in elderly patients, and current management is based on empirical treatment with existing antibiotics, antivirals and anti-inflammatory agents as lifesaving therapies.^2,3

Respiratory fluoroquinolones such as levofloxacin, moxifloxacin are established first-line agents used as monotherapy for community-acquired pneumonia (CAP) or as combination with β-lactam antimicrobials in hospital-acquired pneumonia (HAP).⁴ Owing to their favourable pharmacokinetic properties, respiratory fluoroquinolones are also used to treat severe airway obstruction in patients with comorbidities, and are generally well tolerated, with a safety profile comparable to other antimicrobials.⁵

Dr Pham Khac Tuong shares insights on the respiratory fluoroquinolones use in COVID-19 patients in Vietnam and the post-COVID-19 management of these patients.

Q1: What proportion of your COVID-19 patients developed pneumonia requiring medical intervention or were hospitalised due to respiratory complications? Were these patients more likely to have comorbidities?

At the peak of the epidemic in Vietnam, a large number of patients were hospitalised due to COVID-19 and among this group, patients with pneumonia required further medical intervention. However, actual figures on the number of serious patients who underwent COVID-19-linked respiratory complications hospitalisation is currently unavailable. Currently, with the COVID-19 Omicron variant, the rate of severe cases requiring hospitalisation has decreased significantly compared to the COVID-19 Delta strain.

Most patients requiring hospital admissions often had comorbidities such as Type 2 diabetes, hypertension, pulmonary tuberculosis or other organ tuberculosis, and showed signs of respiratory failure.

Q2: What is your treatment protocol for COVID-19 pneumonia – do you follow your local guidelines for CAP treatment?

The general approach to management is to classify the patient and determine the treatment according to disease severity.

For mild cases with upper respiratory tract infection and mild pneumonia, patients are treated based on established protocols in the Internal medicine or respiratory departments. Antibiotics are typically not prescribed for infections limited to the upper respiratory tract, but patients are regularly monitored. Severe cases of pneumonia require hospitalisation and treatment in the emergency department or intensive care unit. Critical cases which involve severe respiratory failure, ARDS, septic shock, multi-organ failure usually require intensive resuscitation treatment.⁶

In cases of COVID-19 pneumonia, blood and sputum cultures must be followed by appropriate empiric initial antibiotic in case of bacterial co-infections, depending upon severity of infection, age group, and epidemiology as an investigation of aetiology. Antibiotics should be adjusted based on antimicrobial susceptibility test results.

Currently, we use antibiotics according to the CAP treatment guidelines from the Ministry of Health (Vietnam) and refer to the CAP IDSA/ATS guideline (2019) which recommend quinolone monotherapy or a combination therapy with quinolones and betalactams.^7,8

Q3: In patients requiring intervention for COVID-19 pneumonia, what warrants the use of levofloxacin or other respiratory fluoroquinolones, and do you use fluoroquinolones as adjunct therapy with other antimicrobials or as first-line empirical treatment?

As mentioned, we use antibiotics according to the guidelines of the Ministry of Health (Vietnam) as well as IDSA / ATS. If the patient has co-morbidities but no tuberculosis, considering the severity of pneumonia, and no history of allergy to quinolones, patients receive monotherapy with levofloxacin or moxifloxacin or as combination with betalactam while awaiting outcome of sputum culture tests.^7,8

For patients admitted to the hospital with suspected tuberculosis, we use a combination of betalactam and clarithromycin instead of levofloxacin antibiotics.

Q4: How effective were respiratory fluoroquinolones in patients with COVID-19 pneumonia?

During the Delta strain outbreak, COVID-19 patients were susceptible to immunosuppression, with increased risk of bacterial co-infection.

Efficacy of respiratory fluoroquinolones such as levofloxacin was evaluated in hospitalised COVID-19 patients who require treatment for pneumonia. Levofloxacin is a broad-spectrum antibiotic that covers atypical bacteria, so it is often chosen. According to the guidelines dose of 750mg x 5 days is effective and safe for patients.

Q5: Please describe the post-COVID-19 follow-up examinations and supportive care measures in Vietnam? How do you identify patients at risk of developing secondary infections?

Patients need continued home monitoring with twice daily body temperature measurements. If the temperature is above 38 ⁰C for two consecutive measurements or there are other abnormal signs, they must immediately return to the hospital, or health facilities for further examination. Patients must continue with their daily activities with regular exercise and a balanced, nutritious diet. ⁶

The symptoms secondary infection include cough with cloudy sputum, high fever, chest pain, shortness of breath. Patients must return to the hospital 4-6 weeks post- COVID-19 infection, for a follow-up examination and to re-assess organ function.

References

1. Umakanthan S et al, Postgrad Med J. 2020;96:753–758.
2. Ginsburg AS & Klugman KP, Lancet Glob Health. 2020 Dec;8(12):e1453-e1454.
3. Karampela I & Dalamaga M, Arch Med Res. 2020 Oct; 51(7): 741–742
4. Metlay JP, et al. Am J Respir Crit Care Med. 2019;200:e45–e67.
5. Torres A & Liapikou A, Expert Opin. Pharmacother. 2012;13(8):1203-12.
6. Guidelines for diagnosis and treatment of new corona virus (sars-cov-2) COVID-19 in Vietnam
7. Guidelines for the diagnosis and treatment of community-acquired pneumonia in adults 2020 in Vietnam
8. Guidelines IDSA/ATS 2019.