Dr Cao Thi My Thuy

Head of Internal Respiratory Department, Can Tho Central General Hospital

Head of Representative Office, Vietnam Lung Association,

Can Tho, Vietnam

Community-acquired pneumonia (CAP) is a critical public health concern in Vietnam, driven in part by the challenge of differentiating CAP from other respiratory infections like tuberculosis and influenza.^1,2 The rising burden of antimicrobial resistance (AMR) further complicates treatment, necessitating precise and localised approaches to antibiotic use.^2,3

Despite advancements in diagnostics and identifying biomarkers, limited local access to advanced diagnostic tools can hinder timely and accurate management.⁴

In this interview, Dr Cao Thi My Thuy provides expert insights into the current challenges and emerging strategies to enhance CAP care in Vietnam.

Q1: Considering the overlap of symptoms between CAP and other respiratory infections, such as tuberculosis, what challenges do clinicians in Vietnam face in diagnosing CAP, and how are these challenges being addressed?

In Vietnam, CAP accounts for nearly 50% of lower respiratory infections requiring hospitalisation.¹ Of these, approximately one-third of cases involve Mycobacterium tuberculosis. Vietnam is among the countries with a high prevalence of lung tuberculosis (TB),⁵ so physicians always consider the differential diagnosis of lung TB when approaching a case of CAP. The challenge is differentiating between CAP and TB, which present with similar symptoms such as fever, cough, weight loss and shortness of breath, as well as non-specific chest X-ray findings and occasional cases of co-infection.⁶ This makes it difficult to differentiate between the two based on clinical presentation alone.

To address these challenges, the national guidelines for the diagnosis and treatment of CAP and lung TB have been updated, helping clinicians to orient cases that require differential diagnosis based on medical history, recognising symptom patterns, careful physical examination and case-specific imaging analysis. Tests for TB have also evolved, moving from staining for AFB to GeneXpert MTB and culture. Vietnam continues to tackle the challenges of diagnosing CAP amidst TB overlap through improved diagnostics, enhanced healthcare training and clinical integration of TB and pneumonia screening protocols into clinical practice.

Q2: With increasing prevalence of multidrug-resistant organisms (MDROs) in the region, what strategies do you recommend for optimising the initial empirical antibiotic regimen in severe CAP cases?

Vietnam has one of the highest rates of AMR in Asia.³ Studies have shown Streptococcus pneumoniae to be the most common cause of CAP in both children and adults in Vietnam.⁷ Antibiotic resistance in pneumococcal infections complicates the selection of the initial empirical treatment regimen.

Optimising empiric antibiotic therapy is crucial in severe CAP cases, as inadequate initial therapy can lead to poor outcomes. Adhering to national treatment guidelines for selecting antimicrobial therapy is crucial for adult patients with severe CAP.⁸ Treatment strategies include a broad-spectrum beta-lactam ± inhibitory beta-lactamase (e.g. cefotaxim, ceftriaxone, ceftarolin, ampicillin/amoxicillin + clavulanic acid/sulbactam, ertapenem) with a macrolide or fluoroquinolone. The choice of antibiotics should consider local antimicrobial resistance patterns and individual patient factors to optimise treatment outcomes in severe CAP cases.

It is important to start broad-spectrum antibiotics and de-escalate therapy based on pathogen identification and sensitivity results. Rapid microbiological diagnostic tests (PCR) can support early pathogen identification, enabling clinicians to adjust or refine treatment promptly. By integrating early and precise diagnostic methods, risk stratification and continuous surveillance, clinicians can optimize empirical therapy for severe CAP while mitigating the risk of developing further MDR.

For patients with risk factors for infection with Pseudomonas aeruginosa or MRSA, antibiotics that specifically cover these organisms should be selected. Key risk factors include recent hospitalisation or antibiotic use, underlying chronic conditions (e.g., chronic obstructive pulmonary disease, diabetes or immunosuppression), residence in long-term care facilities, and previous colonisation or infection with MDROs.

Q3: What role do newer antibiotics, such as ceftolozane/tazobactam or ceftaroline, play in managing multidrug-resistant (MDR) infections? When is it appropriate to use these agents, and how can they be combined with older antibiotics to improve treatment outcomes, while reducing the risk of antimicrobial resistance?

The management of MDR infections pose a significant challenge in healthcare settings. Newer antibiotics targeting drug-resistant pathogens may help improve treatment efficacy in lower respiratory infections including CAP. Ceftolozane/tazobactam is a beta-lactam + beta-lactamase inhibitor with activity against Pseudomonas aeruginosa including drug-resistant strains.⁹ Ceftolozane/tazobactam has also been found to be effective against other MDR Gram-negative organisms, highlighting its role in combating these difficult-to-treat infections.⁹

Ceftaroline fosamil, a fifth-generation cephalosporin, exhibits broad-spectrum in vitro activity against a range of CAP pathogens, including methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant Streptococcus pneumoniae and non-beta-lactamase-producing Enterobacterales.¹⁰ Clinical trials and meta-analyses have demonstrated its superiority to ceftriaxone in the treatment of CAP.¹¹ The 2024 Updated National Guidelines recommend ceftaroline fosamil in the empirical antibiotic regimen for hospitalised or severe CAP cases, particularly post-influenza pneumonia or suspected MRSA cases.

Ultimately, the choice of antibiotics for treatment also depends on the availability of drugs and health insurance. Newer antibiotic agents are most appropriate in scenarios where older antibiotics have failed, for high-risk patients, or as part of targeted therapy. When combined with older antibiotics, these agents can improve clinical outcomes, broaden antimicrobial coverage and reduce the development of resistance. Importantly, their use must align with antimicrobial stewardship principles and be guided by local resistance patterns to optimise their benefits while minimising risks.

Q4: How are hospitals in Vietnam managing the challenge of dual infections (e.g., bacterial and viral coinfections) in CAP, especially for immunocompromised patients?

A study conducted in Vietnam that used real-time polymerase chain reaction (PCR) combined with the culture method revealed that 76.3% of CAP cases involve multiple pathogens, including bacteria–bacteria or bacteria–virus coinfections.² Bacteria–virus coinfections are especially common in immunocompromised patients with CAP.

Owing to the difficulty of identifying coinfections early, physicians often initiate broad-spectrum antibiotics alongside antiviral therapy empirically, particularly in severe CAP or immunocompromised patients. Clinical decisions are based on factors such as clinical signs, inflammatory markers and radiological findings.¹² Once the causative pathogen is identified, treatment is adjusted to avoid unnecessary use of antibiotics.

A multidisciplinary approach is crucial for managing severe CAP cases, involving infectious disease specialists, pulmonologists and intensive care specialist to optimise care.¹³ In addition, the use of rapid diagnostic tests is essential to differentiate bacterial CAP from viral infections.¹⁴ These strategies ensure timely and targeted interventions, improving outcomes for vulnerable populations while mitigating the risk of antimicrobial resistance.

Q5: What clinical parameters and biomarkers do you prioritise when determining the timing of an intravenous-to-oral switch in patients with CAP?

In patients with CAP, determining the timing of an intravenous-to-oral antibiotic switch is critical for optimising treatment, reducing hospital stays and minimising complications.¹⁵

The decision to switch is guided by clinical stability, improvement in key biomarkers and the patient’s ability to tolerate oral medication. Signs of clinical stability include afebrile status (≤ 37.8°C) for at least 24 hours, heart rate ≤100 beats per minute, respiratory rate ≤24 breaths per minute, systolic blood pressure ≥90 mmHg without vasopressor, SpO2 ≥90% on room air and mental alertness.¹⁶ In addition, the patient should demonstrate the ability to swallow and tolerate oral medications. Improvement in key biomarkers is demonstrated by reduction in blood leukocyte concentration and decreased C-reactive protein (CRP) and procalcitonin (PCT) levels. Other factors influencing the decision to switch include the bioavailability of oral antibiotics, the severity of CAP, and the causative pathogen identified.¹⁷

This approach ensures a safe transition to oral therapy, rapid recovery and reduces duration of hospital stays and optimises the use of healthcare resources while maintaining optimal clinical outcomes.

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