As they age, elderly patients become more susceptible to infection and diagnostic uncertainty. This can lead to increased levels of antibiotic exposure.
Greater use of antibiotics limits their effectiveness and can result in antibiotic resistance, especially among patients older than 65.
The challenge of managing infection in elderly patients
Compared to younger adults, diagnostic uncertainty is much more pronounced when assessing elderly patients as infections in older patients often present atypically.1
This is associated with:
Increased length of stay
Higher hospital mortality
Increased hospital costs
Decrease diagnostic uncertainty and improve antibiotic decision making by aid of PCT.
Procalcitonin (PCT) has been demonstrated in a range of interventional, randomized, controlled trials to:
High antibiotic use is also reflected in the rise of antibiotic resistance observed in elderly patients compared to patients younger than 65 years.3,4
The impact of PCT-aided antibiotic stewardship (ABS) on antibiotic exposure and mortality was similar in elderly patients as compared to younger adults independent of clinical diagnosis and place of treatment.5
30-day mortality
The highest reduction of antibiotic exposure by a PCT-aided approach was achieved for:
patients with pneumonia (-3.71 days) or other LRTI (-2.32 days
patients with low-severity disease/low outcome risk (SOFA 0-6) (-2.43 days)
patients treated on the ward (or in primary care) (-3.02 days)
Sepsis is a life-threatening medical emergency that affects people of all ages. However, older adults, particularly those who have health issues, are disproportionally affected. Early detection and treatment are essential for survival. PCT testing adds key information to the clinical assessment on the presence, course, and severity of sepsis, allowing clinicians to improve antibiotic decision making.
Sepsis is especially dangerous for elderly patients.
Mortality rates for elderly patients with severe sepsis and septic shock are around 50–60%.9-12 These high death rates occur because the elderly often experience co-morbidities, frequent and extended hospitalizations, weakened immune systems, functional limitations, and general effects of aging like thinning skin, frailty, and a sedentary lifestyle.9
Diagnosis of infection is often difficult and delayed.13 For example, the first symptom of a UTI, a leading cause of infection, is typically confusion and disorientation, making it hard for the patient to describe his or her symptoms. In addition, the presentation of symptoms can be ambiguous or atypical. Moreover, elderly patients may not exhibit fever or other clinical signs of infection or inflammation seen in younger patients, even though seniors are at higher mortality risk.
Additionally, the bladder is often colonized in many elderly people leading to false positive results of the urinalysis that show colonization and not infection. This leads to an over prescription of antibiotics in this patient population.14
The decline in immune function often observed in elderly patients15-17 can result in atypical and frequently subtle (e.g., mild fever or even apyrexia) clinical presentations of bacteremia,15,16,18-20 further increasing the risk of under diagnosis and subsequent delays in the treatment of sepsis.
Given these challenges to diagnosis, and the vulnerability of the geriatric population to infection, having a diagnostic test with high specificity and predictive value is essential. Procalcitonin (PCT) can meet this need. With PCT testing, physicians gain timely information specific to systemic bacterial infection, including its presence, course, and severity.21
One meta-analysis of four studies (760 patients, aged 65 years and older) evaluated the accuracy of procalcitonin in diagnosing systemic bacterial infections in elderly patients.19 It was found that procalcitonin is both specific and sensitive in the diagnosis of severe bacterial infection in elderly patients. As shown in randomized controlled trials, very elderly patients can benefit from the use of PCT as a means of lowering antibiotic exposure. While kidney function in many older patients may be impaired, which can affect biomarker kinetics, there is no evidence that it impacts the usefulness of PCT as a diagnostic tool. As always, test results should be interpreted in the context of clinical findings.