Editors

JoukoLaurila

Infections in Old Age

Essentials

Cell-mediated immunity and part by also humoral immunity diminish in old age.
Possible long-term diseases and age-related physiological changes as well as immunosuppressive medications all impair defence mechanisms and make the diagnostics more difficult.
Typical symptoms of infections are often lacking or they are non-specific (e.g. difficulty in walking, confusion). Even mild infections may cause decompensation of some organ.
Attention should always be paid if a stable condition in an elderly person turns strange in some way, even if there is no deterioration of the general condition nor confusion.
Fever is often absent.

Pneumonia

Predisposing factors for pneumonia in old age are e.g. impaired cough reflex, possible neurological diseases causing impaired functioning of the pharynx and susceptibility to aspiration, obstructive pulmonary diseases, immobilization and heart failure.
The temperature of a pneumonic patient may be normal and cough may be completely absent. Pneumonia may manifest as symptoms of impaired general condition and functioning, confusion, or chest pain.
The most common causative agent in community-acquired pneumonia is Streptococcus pneumoniae (pneumococci), and the first-line antimicrobial drug for this in outpatients is amoxicillin http://www.dynamed.com/condition/community-acquired-pneumonia-in-adults#ANTIBIOTICS_FOR_ADULT_OUTPATIENTS and in hospitalised patients cefuroxime or penicillin G http://www.dynamed.com/condition/community-acquired-pneumonia-in-adults#ANTIBIOTICS_FOR_ADULT_INPATIENTS.
During an influenza epidemic there are often secondary bacterial pneumonias, which are usually caused by Staphylococcus aureus. In this case cefuroxime is a justifiable antimicrobial choice.
The length of treatment for pneumonia is 10 days.
Preventing pneumonia by yearly influenza vaccination http://www.dynamed.com/prevention/seasonal-influenza-vaccination#TOPIC_CRL_3LM_CNB is worthwhile Vaccines for Preventing Influenza in the Elderly. The same applies to pneumococcal vaccine http://www.dynamed.com/prevention/pneumococcal-vaccination#EFFICACY_OF_PNEUMOCOCCAL_VACCINE_IN_ADULTS, the effectiveness of which has also been proven in elderly population Vaccines for Preventing Pneumococcal Infection in Adults.
In prolonged lung infection, the possibility of malignancy as well as of tuberculosis (sputum staining and cultures) should be kept in mind.

Urinary tract infections and pyelonephritis

Women are predisposed to urinary tract infections because of age-related atrophy of the vaginal mucosa or prolapses of the vagina or uterus. Men are predisposed because of prostate hyperplasia. The most important external factor predisposing for urinary tract infection is cathetrization. An indwelling catheter should always be removed as soon as possible.
In the elderly, single dose antimicrobial treatment is less effective than courses lasting for more than 3 days Antibiotic Duration for Lower Urinary Tract Infections in Elderly Women http://www.dynamed.com/condition/uncomplicated-urinary-tract-infection-uti-pyelonephritis-and-cystitis#DURATION_OF_ANTIBIOTICS.
The cause of recurrent infections should be defined and treated. Prophylactic pharmacotherapy should be avoided. In exceptional cases it can be considered for a specific period with, e.g., trimethoprim as one dose at night for 6-12 weeks. Nitrofurantoin and quinolones should be avoided. Use of cranberry juice is probably beneficial. Strengthening of the mucosal membranes with local oestrogen (oestriol, oestradiol) is often effective Vaginal Oestrogens for Preventing Recurrent Urinary Tract Infection in Postmenopausal Women.
Treatment should always be based on symptoms and a bacterial culture of an appropriately taken sample.
Symptomless bacteriuria of the elderly is common and it should not be treated without some specific (dysuria, frequency) symptoms suggestive of an infection. Symptomless bacteriuria should not either be accepted as the reason for the patient's weakened general condition.
Treatment should not be started on the basis of a smell combined with a suspicion of an infection.
Cefuroxime intravenously is the first-line management of pyelonephritis. When the general condition improves or when the temperature normalizes, oral medication based on sensitivity testing may be substituted for the i.v. drug. The length of treatment is at least 10 days http://www.dynamed.com/condition/uncomplicated-urinary-tract-infection-uti-pyelonephritis-and-cystitis#ANTIBIOTIC_SELECTION_FOR_ACUTE_PYELONEPHRITIS.
Patients with an indwelling catheter should not be given prophylactic medication. Taking follow-up samples from the catheter is not worthwhile. Chronic bacteriurias (e.g. Pseudomonas) are common among elderly people wearing catheters, and these should not be treated if there are no general symptoms http://www.dynamed.com/condition/catheter-associated-urinary-tract-infection-cauti#TREATMENT_OVERVIEW.

Gastrointestinal and intra-abdominal infections

Because the sense of visceral pain is decreased with ageing, acute appendicitis and biliary tract infections may be difficult to diagnose. They may silently lead to perforation or acute abdominal catastrophe.
Diverticulosis and diverticulitis are age-related diseases.
Plasma CRP and blood leukocyte count, repeated clinical examination and exclusion of infections affecting other organs and eventually abdominal CT scan help to reach the correct diagnosis.

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Information

Editors

Infections in Old Age

Essentials

Pneumonia

Urinary tract infections and pyelonephritis

Gastrointestinal and intra-abdominal infections