General medicine and geriatrics, where is the difference? The example of infective disease

Geriatric medicine differs from internal medicine not in quality, but rather in the probability structures of diagnosis and outcome, presentation of illness and the need for explicit determination of aim of intervention. Older people need more investigation than the young if comparable levels of diagnostic accuracy are to be obtained. In view of the progressive loss of adaptability with its loss of sufficient functional and social reserves, the old more often need a formal program of rehabilitation than younger patients. Infectious diseases exemplify this difference. Age associated impairment of immunity, such as lower T-cell activity and IL-2 production, are associated with an increasing lethality of infections, and permit the reactivation of latent infections. The loss of adaptability has its impacts on mental functioning by increasing the risk of delirium as a consequence of infectious diseases or drug side effects. The cryptic presentation of illness makes even severe infections such as endocarditis, peritonitis or tuberculosis difficult to diagnose. The traditional exclusion of older people from research studies contributed to the still prevailing underestimation of the complexity and need of adequate therapy in geriatric patients.