To the Editor.
—As Dr. Kats mentions, the unpredictability of attacks in FMF makes trials of any therapy difficult. Although he has not encountered any patients whose attacks of fever occurred at regular intervals, we have. These patients are included in the report. The results of treatment in our cases were encouraging, not conclusive, as stated in the article.Secondly, although Dr. Kats urges care in making a "correct" diagnosis, in diseases of unknown cause, specific labeling may only lead to greater confusion. For example, it may be argued now, on the basis of reasonable evidence in a study by George et al (J Clin Invest 48:558, 1969), that etiocholanolone fever, which Dr. Kats calls an "entity," is not a valid diagnosis for syndromes of periodic fever. The authors believe that the diagnoses of periodic fever, including the syndrome of FMF, are accurate descriptive terms to apply to the