122 LETTERS tensive Patients with Idiopathic Systemic Lupus Erythematosus,” by Michael J. Reza and coworkers (1). Penicillamine in Ankylosing Spondylitis 1. Two of the 7 patients were black and it should be To the Editor: Penicillamine is a useful drug in the treatment of rheumatoid arthritis. Recently it was used in ankylosing spondylitis (AS) with promising results ( I ) . We report here a patient with long-standing AS and severe peripheral arthritis who was successfully treated with penicillamine. The 29-year-old patient was admitted to our unit because of severe peripheral arthritis. At the age of 15 AS was diagnosed. At the age of 23 a left hip replacement was performed. Nine months before his admission, he developed severe arthritis on the right knee and both ankles. Treatment with several antiinflammatory drugs was unsuccessful as were local steroid injections. Penicillamine, 250 mg daily, was started and the dose increased every 4 weeks. After 4 months of treatment (daily dosage: 1.0 g) his condition improved, the inflammatory signs disappeared, and he could walk without difficulty. On followup of 9 months, no signs ofjoint inflammation were noticed. No conclusion can be drawn from a single case. Golding stressed the influence of the drug on sacroiliitis (1). We are not aware of other trials of penicillamine for treating AS with peripheral arthritis. The promising results of Golding and the good response in the present case stress the need for further trials before the role of penicillamine in the treatment of severe peripheral arthritis in AS can be established. noted that there are practically no well documented cases of blacks getting hydralazine-induced lupus (2). 2. The 2 black patients had the drug for only 5 and 9 months respectively. As the authors point out and we agree, it usually takes a longer period of exposure to the drug to develop the SLE-like symptoms (2). 3. Acetylation rates would have been of interest here, as it is the slow acetylators who appear t o be predisposed to develop hydralazine-SLE (3). We have found the incidence of slow acetylators in idiopathic SLE to be about 66% (4).Therefore at best 3 of the 5 white patients might be slow acetylators and thus predisposed to develop the syndrome, which has an approximate incidence of 10% in patients receiving high doses of the drug who are white and slow acetylators. 4. Another point to remember is that drug-induced SLE is characterized not by antibodies to native DNA but by an increased incidence of antibodies to DNP and single-stranded DNA ( 5 , 6). 5 . Antibodies to single-stranded DNA were not measured in this study, and thus the data concerning complement, which is usually normal in hydralazine syndrome, and antibodies to native DNA are not relevant to h ydralazine-induced disease. 6. All of the patients were receiving therapy and it is well known that hydralazine SLE does respond clinically to steroids. It is therefore possible that therapy may have masked any clinical signs of SLE produced by the hydralazine. REFERENCE 1. Golding DN: Abstracts VIII, European Rheumatology Congress, Scand J Rheumatol (suppl 8) Y. SCHARF, M.D. M . NAHIR, M.D. The B. Shine Rhewnatology Department Rambam University Hospital Haifa, Israel Hydralazine Therapy in Idiopathic SLE To the Editor: We would like to make a few comments on the interesting article on “Hydralazine Therapy in Hyper- We think it is the impression of many physicians who are responsible for the care of patients with SLE, including ourselves, that the so-called lupus-provoking drugs such as hydralazine, procainamide, INH, and many of the others that are related to the occurrence of antinuclear factors, may be used in lupus patients if there are very specific indications and if the patients are followed carefully. In the present state of knowledge, it is quite possible that the population at risk from druginduced lupus is different from that at risk from idiopathic lupus in terms of etiology, pathogenetic mechanisms, genetic responses, and metabolic pathways. We would therefore encourage the study of a larger number of patients, employing the procedures relevant to druginduced lupus, so that the safety of such drugs in idiopathic SLE can be confirmed.