Clinical efficacy and safety of chelation treatment with typical penicillamine in cross combination with DMPS repeatedly for Wilson's disease

Management Perspective of Wilson's Disease: Early Diagnosis and Individualized Therapy

Wilson's disease (WD) is an inherited disease caused by mutations in ATP7B and is characterized by the pathological accumulation of copper in the liver and brain. Common clinical manifestations of WD include a wide range of liver disease and neurological symptoms. In some patients, psychiatric symptoms may be the only manifestation at the time of diagnosis. The clinical features of WD are highly variable and can mimic any disease of internal medicine. Therefore, for unexplained medical diseases, the possibility of WD should not be ignored. Early diagnosis and treatment can improve the prognosis of WD patients and reduce disability and early death. Gene sequencing is becoming a valuable method to diagnose WD, and if possible, all WD patients and their siblings should be genetically sequenced. Copper chelators including D-penicillamine, trientine, and dimercaptosuccinic acid can significantly improve the liver injury and symptoms of WD patients but may have a limited effect on neurological symptoms. Zinc salts may be more appropriate for the treatment of asymptomatic patients or for the maintenance treatment of symptomatic patients. High-quality clinical trials for the drug treatment of WD are still lacking, therefore, individualized treatment options for patients are recommended. Individualized treatment can be determined based on the clinical features of the WD patients, efficacy and adverse effects of the drugs, and the experience of the physician. Liver transplantation is the only effective method to save patients with acute liver failure or with severe liver disease who fail drug treatment.

Combined sodium Dimercaptopropanesulfonate and zinc versus D-penicillamine as first-line therapy for neurological Wilson's disease

BACKGROUND

Even though recent research has achieved significant advancement in the development of therapeutic approaches for Wilson's diseases (WD), the current treatment options available for WD are still limited, especially for WD patients with neurological symptoms. This study is intended to compare the therapeutic approaches for WD patients with neurological symptoms receiving either combined sodium 2, 3-dimercapto-1-propane sulfonate (DMPS) and zinc treatment or D-penicillamine (DPA) monotherapy as first-line therapy, and identify the more effective therapeutic approach.

METHODS

The case records of 158 patients diagnosed with neurological WD were retrospectively analyzed. These patients treated with intravenous DMPS + Zinc and in combination with oral zinc as a maintenance therapy (Group 1) or DPA alone (Group 2) for 1 year. During the period of treatment, the neurological symptoms of the patients were assessed using the Global Assessment Scale (GAS) and Barthel index. The key hematological and biochemical parameters of the patients (such as the levels of aminotransferase, serum ceruloplasmin, 24-h urine copper excretion), as well as adverse effects were recorded and analyzed.

RESULTS

Ninety-three patients in Group 1, displayed decreased GAS scores and increased Barthel indexes consistently in comparison with the baseline (P < 0.01). Among them, 82 patients (88.2%) exhibited significant neurological improvement after 1 year, while 8 patients (8.6%) experienced neurological deterioration. Among the 65 patients in Group 2, 37 patients (58.5%) exhibited neurological improvements, while 17 patients (26.2%) experienced neurological deterioration after 1-year follow up. Six patients discontinued their treatment midway due to their exacerbating neurological symptoms. A comprehensive comparison of the effectiveness of the two courses of treatment revealed that patients in group 1 demonstrated a higher improvement ratio (P < 0.01) and lower worsening ratio of the neurological symptoms for the patients (P < 0.01) in comparison to the patients in group 2. Meanwhile, renal function, liver enzyme and blood cell counts remained stabilized in group1.

CONCLUSIONS

This study indicates that the combined therapeutic approach of DPMS and zinc may be a preferred first-line therapy in treating the neurological symptoms of WD, in comparison to the treatment with DPA.

Advances in Treatment of Wilson Disease

Background

Wilson disease (WD) is an inherited neurometabolic disorder that results in excessive copper deposition in the liver and the brain, affecting children and young adults. Without treatment the disease is invariably fatal. Though treatments for WD have been available since the 1950s, the disease continues to be associated with considerable morbidity and mortality because of missed diagnosis, and delayed or inadequate treatment. In this paper we survey WD-related literature in order to review recent advances in WD treatment.

Methods

We performed a literature search using the PubMed database for articles relating to WD and its medical treatment. We reviewed the articles, and cross-references of relevant articles, to summarize the current practices for treatment of WD.

Results

The survey shows that if WD is properly treated, in most patients the liver can be stabilized, even severe neurological disability reversed, and patients can resume normal lives.

Discussion

Medical treatment for WD includes use of copper chelators (penicillamine, trientine, dimercaprol, dimercaptopropane sulfonate, and ammonium tetrathiomolybdate) and drugs that decrease gastrointestinal copper absorption. Our knowledge of the treatment approaches has benefited from the large systematic clinical studies that have been conducted over the last decade. For each drug used to treat WD, we surveyed its development, indication for use, dosing, efficacy, and adverse effects.

Wilson's Disease in China

Wilson's disease (WD) is an autosomal recessive disorder of copper metabolism. Its incidence is higher in China than in western countries. ATP7B is the causative gene and encodes a P-type ATPase, which participates in the synthesis of holoceruloplasmin and copper excretion. Disease-causing variants of ATP7B disrupt the normal structure or function of the enzyme and cause copper deposition in multiple organs, leading to diverse clinical manifestations. Given the variety of presentations, misdiagnosis is not rare. Genetic diagnosis plays an important role and has gradually become a routine test in China. The first Chinese spectrum of disease-causing mutations of ATP7B has been established. As a remediable hereditary disorder, most WD patients have a good prognosis with an early diagnosis and chelation treatment. However, clinical trials are relatively few in China, and most treatments are based on the experience of experts and evidences from other countries. It is necessary to study and develop appropriate regimens specific for Chinese WD patients.

Rationale for the Successful Management of EDTA Chelation Therapy in Human Burden by Toxic Metals

Exposure to environmental and occupational toxicants is responsible for adverse effects on human health. Chelation therapy is the only procedure able to remove toxic metals from human organs and tissue, aiming to treat damage related to acute and/or chronic intoxication. The present review focuses on the most recent evidence of the successful use of the chelating agent ethylenediaminetetraacetic acid (EDTA). Assessment of toxic-metal presence in humans, as well as the rationale of EDTA therapy in cardiovascular and neurodegenerative diseases, is reported.

Clinical efficacy of combined sodium dimercaptopropanesulfonate and zinc treatment in neurological Wilson's disease with D-penicillamine treatment failure

OBJECTIVES

There are limited pharmacological treatments for patients with neurological Wilson's disease (WD) and a history of copper-chelating treatment failure.

METHODS

We retrospectively evaluated the clinical records of 38 patients with WD who were treated with sodium dimercaptopropanesulfonate (DMPS) and zinc (group 1) or zinc alone (group 2). All patients had a history of neurological deterioration during their previous treatment with D-penicillamine (DPA).

RESULTS

Twenty-one patients were treated with intravenous DMPS for 4 weeks, followed by zinc gluconate for 6 months, and the treatment protocol was repeated twice. Relative to the baseline, repeated DMPS therapy and zinc maintenance therapy decreased neurological scores continuously (p < 0.01). Sixteen patients (76.2%) demonstrated neurological improvements after 1 year of therapy and four patients (19.0%) exhibited neurological deterioration at the follow-up session. In addition, 17 patients were treated with zinc monotherapy for 12 months. Two patients (11.8%) demonstrated neurological improvements and five patients (29.4%) exhibited neurological deterioration. Compared with the patients in group 2, a greater improvement ratio (p < 0.01) and lower deterioration ratio (p < 0.01) were observed in the patients in group 1 after 1 year of therapy.

CONCLUSIONS

Our findings indicate that the safety and efficacy of combined treatment of DMPS and zinc is superior to those of zinc monotherapy in patients with neurological WD with a history of DPA treatment failure.

Diagnosis and management of fulminant Wilson's disease: a single center's experience

BACKGROUND

Medical therapy is rarely effective in patients with fulminant Wilson's disease (FWD). Liver transplantation is limited by the lack of donor liver in most patients with FWD at the time of diagnosis. New Wilson's index, model for end-stage liver disease (MELD) and Child-Pugh score are useful tools for decision-making of liver transplantation; however, none of them is an independent decisive tool. It is worthwhile to explore a more effective and practical therapeutic strategy and reevaluate the prediction systems for patients with FWD.

METHODS

Nine patients with FWD associated with hemolytic crisis and fulminant hepatic failure (FHF) were investigated. The clinical presentation, prognostic score and medical therapies of the patients were analyzed.

RESULTS

In 7 of the 9 patients with FWD who received the comprehensive therapy of corticosteroid, copper-chelating agent (dimercaptopropansulfonate sodium) and therapeutic plasma exchange (TPE), 6 patients recovered from FHF. The remaining one had been improved through the comprehensive therapy but died of septicemia 51 days later. Two patients with spontaneous bacterial peritonitis (SBP) died from liver failure in three or five hospital days without plasma exchange or chelating therapy. All of the 9 patients with FWD presented with acute hepatic failure, severe jaundice and mild to severe hemolytic anemia. No marked difference in the incidence of severe hemolytic anemia was detected between the survival and deceased groups. However, the incidence and the degree of hepatic encephalopathy (HE) in the non-survival group were higher than those in the survival group. Unlike the deceased group, the survival group had no complications induced by bacterial infection. Compared to new Wilson's index, Child-Pugh score and MELD score, the variation of prothrombin activity (PTA) between the survival and deceased groups was more evident.

CONCLUSION

For patients with FWD, the episode of severe hepatic encephalopathy or/and spontaneous bacterial peritonitis indicates worse prognosis, and PTA is a recommendable predictor. An emergent liver transplantation should be considered for patients whose PTA is below 20%, or for those with severe HE or/and SBP. The comprehensive therapy of corticosteroid, copper-chelating agent and TPE is effective for patients without SBP and whose PTA is higher than 20%.

Successful Splenectomy for Hypersplenism in Wilson's Disease: A Single Center Experience from China

Splenomegaly and pancytopenia are common in Wilson's disease (WD) and splenectomy is one of the conventional treatments for splenomegaly and the associated pancytopenia. However, splenectomy remained controversial for hypersplenism in WD as it was reported that splenectomy leaded to serious emotional and neurological deterioration in WD patients with hypersplenism. In the current study, we present our experiences in 70 WD patients with hypersplenism who had undergone splenectomy, outlining the safety and efficacy of splenectomy in WD. The clinical database of 70 WD patients with hypersplenism who had undergone splenectomy in our hospital between 2009 and 2013 were reviewed and followed-up regularly. Before splenectomy, all the patients accepted a short period of anti-copper treatment with intravenous sodium 2, 3-dimercapto-1-propane sulfonate (DMPS). All the patients demonstrated a marked improvement in platelet and leucocyte counts after splenectomy. No severe postoperative complication was observed. In particular, none of the 37 patients with mixed neurologic and hepatic presentations experienced neurological deterioration after splenectomy, and none of the patients with only hepatic presentations newly developed neurological symptoms. During the one year follow-up period, no patient presented hepatic failure or hepatic encephalopathy, no hepatic patient newly developed neurological presentations, and only 3 patients with mixed neurologic and hepatic presentations suffered neurological deterioration and these 3 patients had poor compliance of anti-copper treatment. Quantative analysis of the neurological symptoms in the 37 patients using the Unified Wilson's Disease Rating Scale (UWDRS) showed that the neurological symptoms were not changed in a short-term of one week after splenectomy but significantly improved in a long-term of one year after splenectomy. Additionally, compared to that before splenectomy, the esophageal gastric varices in most patients significantly improved one year after splenectomy. Thus, we may conclude that splenectomy is a safe and effective therapeutic measure for hypersplenism in WD patients who had been preoperatively treated with DMPS for powerful anti-copper therapy.