Drs. Harrow and Sloane, authors of one of the articles mentioned reply in the next letter.
Previous animal experiments with large doses of salicylates (or phenacetin) have failed to produce renal papillary necrosis, although a renal interstitial reaction was identified. Therefore, Dr. Feller's findings are intriguing and may have clinical significance of considerable importance. The details of his method and reasons for his ability to produce the necrosis with salicylates (and acetazolamide) are eagerly awaited.
Present evidence still points to phenacetin rather than salicylates as the etiological agent in the clinical syndrome for the following reasons:
In world-wide reports of kidney damages associated with analgesic abuse, phenacetin was the one compound always present.
In the large number of cases from Switzerland, Saridon was the most widely used preparation, but
Saridon does not contain salicylates. (The formula is isopropylantipyrine, 150 mg; phenacetin, 250 mg; caffeine, 50 mg, and 3,3-diethyl-2,4-dioxo-tetrahydro-pyridine. ) Likewise, in