One hundred years of American internal medicine. A view from the inside.

The term internal medicine began to be used by German writers in the late 19th century to designate a branch of practice incorporating the growing understanding of morbid anatomy, microbiology, physiology, and biochemistry. American practitioners of internal medicine began to take a respected place in world medicine toward the close of the 19th century. Noteworthy changes followed World War II, owing to allocation of large sums of money for biomedical research by governments, philanthropic organizations, and the pharmaceutical industry. Clinical problems in this period shifted in preponderance from acute infections to the chronic diseases that accompany aging. Complex diagnostic procedures, together with a diversity of therapeutic choices, created need for full-time teachers and clinical investigators in medical schools, as well as for subspecialists in practice. The pendulum may have swung too far toward specialization, and in the future a substantial proportion of practitioners of internal medicine will still continue to serve as generalist physicians.