Life-threatening infections: how to choose the right antibiotics.

Pneumococcal pneumonia in two or more lobes in frail, elderly patients; staphylococcal and Gram-negative rod pneumonia in patients of any age; lung abscesses; septicemia; endocarditis; peritonitis; and meningitis are life-threatening infections. To save patients with these infections, the physician should know the causative organism and educate himself by cultures; estimate the whole body bacterial burden and decrease bacterial numbers by incision and drainage where large collections of pus are accessible; choose antibiotics with care and use two antibiotics if serious prognostic signs are present initially, if there is a change for the worse, or if the laboratory report indicates that multiple organisms are present; check the serum bactericidal level and repeat this test if the route of antibiotic administration is changed; watch for and treat underlying disease; and always monitor for septic shock. Aged patients need special care, as they often have severe underlying disease. The bacterial burden is often high before infection is recognized in elderly patients, and age itself interferes with host defenses.