Diagnosing infections in older adults may be challenging because of atypical presentations and the frequent presence of cognitive impairment.
Delirium, falls, or functional decline may be the presenting and, sometimes, only sign of an infection. Fever may be absent.
Hospitalization and deaths as a consequence of pneumonia, influenza, and other respiratory tract infections are common.
Urinary tract infection remains the most common overdiagnosed bacterial infection. Asymptomatic bacteriuria is common in older adults and requires no treatment.
Optimal management of chronic disease, immunizations, prevention of pressure ulcers, attention to infection prevention practices, such as hand hygiene compliance, appropriate gown and glove use, oral hygiene and judicious antibiotic usage, are key preventive measures to reduce infections and enhance quality of care in older adults in skilled nursing facilities.
General Principles in Older Adults
Infections remain a major cause of mortality and morbidity in older adults. With significant progress made in cancer management and cardiovascular diseases, deaths caused by infectious diseases appear to be rising. Pneumonia, influenza, and bacteremia are among the top 10 causes of death in older adults. Approximately 1.5–2.0 million infections occur in skilled nursing facilities per year, making their prevalence a major quality-of-care concern. Infections can lead to increased hospitalizations for this population, exposing them to nosocomial pathogens and resultant complications, such as functional disability, delirium, pressure ulcers, and adverse events. Common infections in older adults include urinary tract infections, upper and lower respiratory tract infections, gastroenteritis including Clostridium difficile diarrhea, skin and soft-tissue infections, including surgical site infections, and osteomyelitis. HIV/AIDS in aging populations will also be an emerging concern as those infected as younger adults now have an increasing life expectancy because of the effectiveness of antiretroviral therapy, and because the number of new infections in older adults is also on the rise.
The risks of developing an infection, its severity, and the outcome from that infection depend on the relationship between the virulence of the pathogen, its inoculum, and the host’s defense system. The ability of a pathogen to attach and replicate in a host environment determines its virulence. In aging adults, macrophage function is altered, mucocutaneous defenses are compromised, cytokine production is diminished, and T-cell function is suboptimal. Comorbid conditions, such as renal failure, diabetes, congestive heart failure, chronic lung diseases, and malnutrition, further exacerbate defense mechanisms. A paucity of presenting signs and symptoms leads to delayed recognition of infection, which can result in poor outcomes. Subtle changes in functional and cognitive decline are often early warning signs. Other presenting atypical symptoms include falls, loss of appetite, fatigue, and failure to thrive. Febrile response is often blunted, especially in frail older adults residing in long-term care facilities. As a result, the Practice Guidelines Committee of the Infectious Diseases of America recommends a clinical evaluation for residents in skilled nursing facilities with single oral temperature over 100°F (37.8°C), ...