Page 32 - Delaware Medical Journal - March/April 2020

EDITORIAL
A Reply to
‘A Common Anti-Hypertensive Causing ANCA-Associated Pauci-Immune Vasculitis’
Peter V. Rocca, MD (Editor-in-Chief, Delaware Medical Journal)
In this issue of the Delaware Medical Journal, Teskin et al. highlight
a relatively rare but potentially
devastating complication of hydralazine use, i.e. ANCA-associated drug-induced vasculitis.
Hydralazine use has been associated with two rheumatic syndromes, viz. drug-induced lupus and drug-induced vasculitis. Interestingly, while the former tends to be relatively mild, e.g. renal involvement is uncommon, the latter can be quite severe. As Peter Merkel’s group from the Massachusetts General Hospital published in a report of 10 cases of hydralazine-associated ANCA-associated vasculitis, nine
had renal involvement1. Despite glucocorticoids and cyclophosphamide (10 and eight patients, respectively), two patients died, and three required hemodialysis (two of whom eventually
recovered). At six-month follow-up, seven patients were in remission.
The mainstay of treatment of ANCA- associated drug-induced vasculitis
is the withdrawal of the putative causative agent which, at times, is
by itself sufficient in arresting the disease. In their report, Teskin et al. may place too much emphasis on the patient’s serologic pattern in order to differentiate between idiopathic and drug-induced vasculitis. Anti-histone antibodies are highly nonspecific and frequently found in asymptomatic patients taking hydralazine. These antibodies can be found in as many of 70% of patients with rheumatoid arthritis, Sjogren’s syndrome, as
well as primary biliary cirrhosis and Alzheimer’s.2 It would, therefore, be imprudent to not withdraw a potentially causative agent, e.g. hydralazine,
propylthiouracil, minocycline, etc. while awaiting serologies in a patient with suspected ANCA-associated vasculitis. Similarly, given the potentially devastating nature of this process, a putative causative agent should not be reintroduced irrespective of the serologic pattern.
REFERENCES
1. Drug-Associated Antineutrophil Cytoplasmic Antibody-Positive Vasculitis: Prevalence Among Patients with High Titers of Antimyeloperoxidase Antibodies. Choi H.K., Merkel P.A., Walker A.M., Niles J.L. Arthritis Rheum. 2000; 43(2):405.
2. Cozzani E., Drosera M., Gasparini G., Parodi, A. (6 February 2014). Serology of Lupus Erythematosus: Correlation Between Immunopathological Features and Clinical Aspects. Autoimmune Diseases. 2014: 321359
80
Del Med J | March/April 2020 | Vol. 92 | No. 2