To the Editor.

The article by Krilov et al concerning childhood and adolescent chronic fatigue syndrome (CFS) is quite problematic. Nowhere in the entire article is any convincing evidence given that CFS is a true medical and scientific entity. All the symptoms and behaviors described are consistent with childhood dysthymia or school avoidance. The one consistent piece of data was that symptoms improved during the summer. The statement, “Although we have not performed formal psychological or psychiatric testing in our patients, our clinical experience makes us believe that the syndrome is more than just an alternate manifestation of depression” is purely anecdotal and conjecture. “Although the etiology of CFS remains unknown, one possibility is that it involves an aberrant immunologic response to an infectious illness that occurs in an individual who is psychologically vulnerable, by virtue of past history of psychological difficulties and/or currently increased levels of stress” is a statement without basis in any of the presented data. No evidence for said mysterious virus is presented. The reader should be referred to the article by Plioplys on CFS in the August 1997 issue (Pediatrics.1997;100:270–271). Plioplys cautions strongly against making the diagnosis of CFS in children and adolescents. Some experience and reason should be applied to the Krilov article.