We appreciate the comments of Dr. Still and concur that the morbidly obese older patient may be declining functionally just as an undernourished older patient might be; this is yet another compelling argument for abandoning failure to thrive as a diagnosis because it reinforces the stereotype of the wasting patient as the only one who qualifies for the label. Although it was not the purpose of our paper to provide a comprehensive differential diagnosis for patients who are declining, we agree with Dr. Stead that tuberculosis is a diagnosis that is often overlooked.

Dr. Portnoi is mistaken in claiming that we see no difference between the concepts of failure to thrive and naturalness of death. Certainly there is nothing more gratifying for an internist than to diagnose occult reversible illness in a declining patient and facilitate his or her recovery. No data exist, however, to indicate how often and in which clinical settings this reversal occurs. In our paper, we emphasize that it is just this type of data that we badly need in order to distinguish between patients undergoing a natural death and those likely to benefit from our interventions.

Dr. Gordon wisely points out that the concept of failure to thrive should not be abandoned simply because it is frequently misused by some clinicians. Unlike pediatricians, however, who diagnose failure to thrive in their patients on the basis of objective percentiles of height, weight, and other milestones, geriatricians treat patients who even in the best of health sometimes experience some level of physical decline. This central distinction complicates a transposition of the term from children to adults. We believe that it is more useful for clinicians to deconstruct the concept of failure to thrive into measurable domains-impaired physical functioning, malnutrition, depression, and cognitive impairment-in order to more precisely define the nature of the underlying problem and guide investigation and possible treatment. What we propose, then, is an explicit articulation of clinical judgment when something seems "not quite right" about the presentation of an older patient who cannot offer a specific chief problem.