CAP in elderly: Diagnosis challenges and optimisation of antimicrobial therapy

24 June, 2021

Shen Ning, Chief Physician, Professor, Doctoral supervisor, Vice President of Peking University Third Hospital, Director of Infectious Diseases Centre, Deputy Director of Department of Respiratory and Critical Care Medicine. She is serving as Deputy Group Leader of Infection Study Group of Respiratory Diseases Branch of Chinese Medical Association, Vice Chairman of the Foreign Affairs Working Committee of the Respiratory Physician Branch of the Chinese Medical Doctor Association, Standing Committee Member of Respiratory Endoscopy and Interventional Branch of Beijing Medical Association, Standing Committee Member of the Clinical Respiratory Professional Committee of the Chinese Women Physicians Association, Member of the Infectious Disease Professional Committee of China Medical Education Association, Member of the Anti-infective Pharmacology Professional Committee of Beijing Pharmacological Society.


Q1. The Seventh National Population Census of the People’s Republic of China was released recently and ageing is becoming an increasing concern. Please describe the incidence and characteristics of community-acquired pneumonia (CAP) – a disease common among the elderly.

The 7th census reported an 18.7% of population (i.e., 264,020,000 people) over 60 years old, of which 13.5% (190,640,000 people) are over 65. These statistics suggest that China’s older population is growing much faster and the country will be feeling the impact of the rapidly ageing population.

CAP in the elderly is commonly defined as the incidence of pneumonia in adults aged 65 years and above. The incidence of CAP among the elderly over 65 years old (28.7%) is significantly higher than that of the younger adults (aged 26–45 years). The incidence of CAP increases with age. Studies in Japan have reported that incidence of CAP in the elderly over 65 is as high as 70%, and approximately 70% of these patients require hospitalisation – causing a heavy financial burden.

In addition to the high rate of incidence and high mortality rate, elderly CAP also has the following characteristics: 1. Various comorbidities such as chronic obstructive pulmonary disease (COPD), diabetes, cardiovascular diseases, and Parkinson’s disease. These underlying diseases are risk factors for CAP but can also cause complications; 2. There are many limiting factors in diagnosing and treating the elderly, especially the extremely old. Lifestyle circumstances such as being bedridden and having difficulty in caring for themselves could lead to poor oral hygiene and increase in oropharyngeal colonisation. An increase in medication could also present a high number of drug-drug interactions and adverse reactions.


Q2. What are the difficulties and challenges in diagnosing and treating elderly CAP patients? What should we pay particular attention to?

Some difficulties in diagnosing and treating elderly CAP patients include: 1. Atypical clinical manifestation of elderly CAP. CAP can present as loss of appetite, urinary incontinence, fatigue and altered mental state. Other symptoms such as fever, cough, and increase in white blood cells or neutrophils may not be obvious and could easily be overlooked or misdiagnosed; 2. The diversity of causative pathogens: Streptococcus pneumoniae remains the most common pathogen of elderly CAP. However, other Gram-negative and anaerobic bacteria, as well as viruses are also common pathogens of CAP. The elderly have weak voluntary expectoration. Along with underlying diseases, this limits the invasive procedures we can perform – causing sample collection a huge challenge.

It is noteworthy that: 1. Shortness of breath is a sensitive and commonly observed indicator of elderly CAP. When an elderly present with fever, lethargy or atypical symptoms such as confusion, chest imaging should be conducted quickly to make a clear diagnosis. Chest CT scans are sensitive and specific in diagnosing CAP. It is helpful in quickly ruling out or confirming diagnoses in patients with acute and severe symptoms or atypical symptoms. This could prevent the unnecessary use of antimicrobial agents and reduce side effects; 2. Aspiration pneumonia is common among the elderly, making up 70% of elderly CAP. During diagnosis, it should be ascertained if inhalation is a risk factor and whether the position of lesion in the chest imaging is in the hypostatic region such as the upper posterior segment, lower superior segment, or posterior basal segment.


Q3. It is crucial to optimise antimicrobial therapy for the treatment of elderly patients with CAP. Please tell us about your experience in choosing antimicrobial agents.

S. pneumoniae is the main causative pathogen of elderly CAP. However, for elderly patients with underlying diseases (such as congestive heart failure, cardiovascular and cerebrovascular diseases, chronic respiratory diseases, renal failure, and diabetes), we should consider the possibility of Enterobacteriaceae infection and further evaluate the risk factors of extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae. Based on experience, cephalosporins, piperacillin/tazobactam, cefoperazone/sulbactam, ertapenem or other carbapenems can be selected for patients with high risk of ESBL-producing drug-resistant bacteria. The new quinolone, sitafloxacin, is also more effective against ESBL-producing Enterobacteriaceae. Related risk factors include having a history of ESBL-producing Enterobacteriaceae colonisation or infection, having used cephalosporin during the early stage, repeated or long-term hospitalisation, having medical implants, and having renal replacement therapy.

Ensure that anaerobic bacteria, Gram-negative bacteria, and Staphylococcus aureus are covered when the cause is by inhalation. Select drugs that are effective against anaerobic bacteria, such as amoxicillin/clavulanic acid, ampicillin/sulbactam, moxifloxacin, sitafloxacin, and carbapenems, or in combination with metronidazole or clindamycin according to the severity of the disease.

The elderly have decreased organ function. Take note of the function of each organ during treatment to avoid side effects. Decrease in renal excrement function prolongs the half-life of the drug. Adjust the dosage according to the patient’s age and creatinine clearance rate. During antibiotic treatment, closely monitor complications and avoid the occurrence of acute exacerbation.

I recommend active vaccination of the elderly without contraindications against pneumonia and influenza.



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