Viral Infections

Infection in the elderly

Many functional, demographic, and immunologic changes associated with aging are responsible for increasing the incidence and severity of infectious diseases in the elderly. Management is complicated by age-related organ system changes. Because many of the elderly are on multiple medications for underlying illnesses, antimicrobial therapy needs to be chosen keeping drug interactions and adverse events in mind. Common infections seen in the elderly are infections of skin and soft tissue, urinary tract, respiratory tract, and gastrointestinal tract. Organized and well-funded programs to address infectious disease issues in the elderly are the only way to improve care.

Infectious Emergencies in the Elderly

As life expectancy continues to rise, the number of geriatric patients will increase and the percentages of geriatric patients seen in the emergency department will reflect those numbers. Emergency physicians are responsible for making immediate diagnoses and initiating expeditious treatment. Infectious diseases in the elderly are more prevalent, challenging to diagnose, and are associated with greater morbidity and mortality than with the younger patient population.

[Using antibiotics in case of influenza]

Acute respiratory bacterial infection is the most common complication of influenza and a leading cause for excess rate of outpatient visits, hospitalization, and death (pneumonia). Influenza promotes bacterial infection as stated by epidemiologic evidence of temporal association between outbreaks or peaks of both influenza and bacterial pneumonia. The bacteria involved are Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus. However, Gram-negative rods, Klebsiella pneumoniae, Pseudomonas aeruginosa, anaerobes and methicillin resistant S. aureus may be involved in institutionalized elderly patients. Various studies confirm that antibiotics are over-prescribed in patients with influenza or influenza like illness, even in the absence of bacterial infection signs, and in patients without comorbidity. No data has proven the benefice of antibiotic prescription in influenza-infected patients without bacterial infection. Neuraminidase inhibitors may be of interest for the management of influenza infected patients, because they can decrease the risk of bacterial complications and the use of antibiotics.

Measuring the impact of influenza on the hospital admission rates of the elderly in Ontario: a five-year admission rate analysis, 1988-1993

OBJECTIVE

A retrospective study was conducted to compare age- and sex-specific rates of hospital admission of the elderly in Ontario for five influenza seasons from 1988-1993 for pneumonia, congestive heart failure and chronic respiratory disease.

RESULTS

Significant increases in admissions were found for pneumonia in each influenza season for both sexes. Admissions were significantly increased for congestive heart failure for the oldest males in all years; and for four of five years for the youngest two age groups of males. For females significant increases in admissions occurred in the oldest two age groups in each influenza season; and for three of five seasons for the youngest age group. For chronic respiratory disease, significant increases in admissions were found for each influenza season for all years for the two youngest age groups of males and females.

CONCLUSION

The impact of influenza is substantial in terms of morbidity in the elderly.

Vitamin E and infectious diseases in the aged

The incidence of infectious diseases, particularly respiratory diseases, increases with age. Age-associated decline in immune function contributes to the increased susceptibility of the aged to infections. Vitamin E supplementation has been shown to improve some aspects of immune function in aged animals and human subjects. The protective effect of vitamin E against viral or bacterial infections in experimentally-challenged young animals has been reported. We investigated the effects of supplementation with vitamin E and other antioxidants on resistance to influenza infection in young and old animals. While vitamin E-supplemented young mice showed only a modest reduction in lung viral titre, vitamin E-supplemented old mice exhibited a highly significant (P < 0.05) reduction in viral lung titre. In subsequent studies, we focused on the mechanism of vitamin E-induced reduction of influenza viral titre. The results of these studies as well as those reported by other investigators on the relationship between vitamin E and infectious diseases will be reviewed.

Wegener's granulomatosis in the elderly

STUDY OBJECTIVE

To determine if elderly patients with Wegener's granulomatosis (WG) exhibit distinctive clinical features or outcomes compared with patients whose conditions were diagnosed at younger ages.

DESIGN

Retrospective cohort study.

SETTING

University medical center.

PATIENTS

Thirty-three patients with WG diagnosed when 60 years old or older and 34 patients with WG diagnosed at age younger than 60 years, identified by record review of all WG patients seen over an 11-year period.

RESULTS

The prevalence of specific clinical features, progression to end-stage renal disease, mortality rate, and infectious and noninfectious complications of therapy were examined. The prevalence of upper respiratory tract involvement (rhinitis, sinusitis, otitis, epistaxis) and hemoptysis were significantly less common as initial manifestations in the elderly patients, although pulmonary infiltrates were seen more commonly during the course of their disease. Renal insufficiency was more common at the time of diagnosis in the elderly patients (64% vs 35%; p < 0.05). Most notably, CNS involvement was 4.5-fold more common in elderly patients (27% vs 6%; p = 0.02). The overall incidence of infectious and noninfectious complications of therapy was similar between the groups, although the mortality rate was markedly higher in the elderly patients (54% vs 19%; p < 0.01). Almost all deaths were due to overwhelming infection.

CONCLUSIONS

Elderly patients with WG present with distinctive clinical features, particularly a relatively low incidence of upper respiratory tract complaints and a high incidence of CNS involvement. The mortality risk from infectious complications of WG is substantially higher in elderly patients, although this cannot be attributed directly to adverse affects of therapy.

Infections and antibiotic resistance in nursing homes

Infections occur frequently in nursing home residents. The most common infections are pneumonia, urinary tract infection, and skin and soft tissue infection. Aging-associated physiologic and pathologic changes, functional disability, institutionalization, and invasive devices all contribute to the high occurrence of infection. Antimicrobial agent use in nursing homes is intense and usually empiric. All of these factors contribute to the increasing frequency of antimicrobial agent-resistant organisms in nursing homes. Programs that will limit the emergence and impact of antimicrobial resistance and infections in nursing homes need to be developed.

Patient assessment. Infection in the elderly

1. Along with a decrease in immune competence, older adults are found to have reduced sensitivity of several homeostatic mechanisms that will also predispose them to the development of infection. 2. Common infections in the elderly include pneumonia, tuberculosis, urinary tract infections, and skin infections. 3. Nursing can play a pivotal role in the prevention of infection in the older adult by providing information on the importance of influenza and pneumococcal vaccines, instituting early risk assessment identification, and developing proactive nursing interventions for those individuals at risk.