Withdrawal of penicillamine from zinc sulphate-penicillamine maintenance therapy in Wilson's disease: promising, safe and cheap.

BACKGROUND: Penicillamine, once considered the cornerstone of treatment for Wilson disease (WD), is rather expensive and toxic, and often causes neurological worsening. Zinc sulphate, aiming at the treatment of free-copper toxicosis, has emerged as effective, safe and cheap alternative. AIM: To assess the effect of withdrawal of penicillamine from maintenance treatment with penicillamine and zinc sulphate. PATIENTS AND METHODS: 45 patients of WD (M:F: 28:17; age at diagnosis: 13.5+/-63 years), on both penicillamine (P) and zinc sulphate (Zn), couldn't continue penicillamine due to financial constraints. Their clinical data, disability and impairment scores (Schwab and England (S&E) score, Neurological Symptom Score (NSS), and Chu staging) and follow-up data of patients maintained only on zinc sulphate were recorded. RESULTS: Majority of patients (84.4%) had neuropsychiatric manifestations. The mean duration of treatment with penicillamine (P) and zinc sulphate (P+Zn), before stopping penicillamine, was 107.4+/-67.3 months. 40 patients improved variably, while the rest didn't. They received only zinc sulphate for 27.2+/-8.5 months (range: 12 to 34) and 44 patients (97.7%) remained status quo or improved marginally. Only one patient reported worsening in dysarthria. Their disability and impairment scores during combination (penicillamine and zinc sulphate) and Zn alone were: Chu (1.3+/-0.5 vs. 1.5+/-1.9; p=0.4), NSS (1.8+/-3.1 vs. 1.5+/-2.3; p=0.03) and S&E (96.4+/-5.6 vs. 98.6+/-3.5; p=0.03). There were no adverse effects. CONCLUSIONS: Withdrawal of penicillamine from zinc sulphate/penicillamine maintenance therapy for patients with Wilson's disease was effective, safe and economic, for almost all patients. This retrospective study reiterates that zinc sulphate may be used as a preferred mode of treatment for patients with Wilson's disease.