Zinc monotherapy from time of diagnosis for young pediatric patients with presymptomatic Wilson disease

EASL-ERN Clinical Practice Guidelines on Wilson's disease

Wilson's disease is an autosomal recessive disorder of copper metabolism which affects the liver, brain and other organs. Diagnosis is based on: clinical features; biochemical tests, including plasma ceruloplasmin concentration, 24-h urinary copper excretion, copper content in the liver; and molecular analysis. Leipzig score and additionally relative exchangeable copper determination are recommended for diagnosis. Pharmacological therapy comprises chelating agents (penicillamine, trientine) and zinc salts, while only chelators are recommended for significant liver disease. Monitoring is based on clinical symptoms, liver tests and copper metabolism (urinary copper excretion, exchangeable copper) to detect poor compliance and over/under-treatment. Acute liver failure is challenging as making a diagnosis is difficult and pharmacological therapy may not be sufficient to save life. Liver transplantation has a well-defined role in Wilsonian acute hepatic failure but may also be considered in neurological disease.

Efficacy and safety of D-penicillamine, trientine, and zinc in pediatric Wilson disease patients

OBJECTIVES

Wilson disease (WD) is a rare genetic disease affecting copper metabolism and the biliary tract's copper excretion. Lifelong medication is necessary to prevent liver failure, neurological complications, and death. Although D-penicillamine (DPA), trientine, and zinc are used to treat WD, there is limited research on the long-term outcomes of these drugs, especially in children. This study aimed to evaluate the efficacy and safety of DPA, trientine, and zinc in patients diagnosed with WD during childhood.

METHODS

Ninety out of 92 patients were included in the analysis, excluding two patients who underwent liver transplantation without drug treatment due to an acute liver failure diagnosis. Treatment outcomes and reasons for discontinuation of therapy in 148 treatment blocks (37 DPA, 50 trientine, and 61 zinc) were analyzed using Kaplan-Meier analysis.

RESULTS

The median age at diagnosis was 8.3 years. There was a statistically significant difference in drug changes due to treatment ineffectiveness among the three drugs: trientine (22/50, 44%), zinc (15/61, 25%), and DPA (2/37, 5%) (all p < 0.05). Regarding drug changes due to adverse effects, the rate was the highest for DPA, followed by zinc and trientine. There were significant differences between DPA and zinc, zinc and trientine (all p < 0.05), but no significant difference was observed between DPA and zinc (p = 0.22).

CONCLUSIONS

In pediatric WD, DPA, zinc, and trientine have therapeutic effects in that order. However, DPA and zinc are associated with more adverse effects compared to trientine.

Analysis of risk factors for neurological symptoms in patients with purely hepatic Wilson's disease at diagnosis

OBJECTIVE

To analyze and explore the risk factors for neurological symptoms in patients with purely hepatic Wilson's disease (WD) at diagnosis.

METHODS

This retrospective study was conducted at the First Affiliated Hospital of the Guangdong Pharmaceutical University on 68 patients with purely hepatic WD aged 20.6 ± 7.2 years. The physical examinations, laboratory tests, color Doppler ultrasound of the liver and spleen, and magnetic resonance imaging (MRI) of the brain were performed.

RESULTS

The elevated alanine transaminase (ALT) and aspartate transaminase (AST) levels and 24-h urinary copper level were higher in the purely hepatic WD who developed neurological symptoms (NH-WD) group than those in the purely hepatic WD (H-WD) group. Adherence to low-copper diet, and daily oral doses of penicillamine (PCA) and zinc gluconate (ZG) were lower in the NH-WD group than those in the H-WD group. Logistic regression analysis showed that insufficient doses of PCA and ZG were associated with the development of neurological symptoms in patients with purely hepatic WD at diagnosis.

CONCLUSION

The development of neurological symptoms in patients with purely hepatic WD was closely associated with insufficient doses of PCA and ZG, and the inferior efficacy of copper-chelating agents. During the course of anti-copper treatment, the patient's medical status and the efficacy of copper excretion should be closely monitored.

The Role of Zinc in the Treatment of Wilson’s Disease

Wilson’s disease (WD) is a hereditary disorder of copper metabolism, producing abnormally high levels of non-ceruloplasmin-bound copper, the determinant of the pathogenic process causing brain and hepatic damage and dysfunction. Although the disease is invariably fatal without medication, it is treatable and many of its adverse effects are reversible. Diagnosis is difficult due to the large range and severity of symptoms. A high index of suspicion is required as patients may have only a few of the many possible biomarkers. The genetic prevalence of ATP7B variants indicates higher rates in the population than are currently diagnosed. Treatments have evolved from chelators that reduce stored copper to zinc, which reduces the toxic levels of circulating non-ceruloplasmin-bound copper. Zinc induces intestinal metallothionein, which blocks copper absorption and increases excretion in the stools, resulting in an improvement in symptoms. Two meta-analyses and several large retrospective studies indicate that zinc is equally effective as chelators for the treatment of WD, with the advantages of a very low level of toxicity and only the minor side effect of gastric disturbance. Zinc is recommended as a first-line treatment for neurological presentations and is gaining acceptance for hepatic presentations. It is universally recommended for lifelong maintenance therapy and for presymptomatic WD.

Orphan Drug Use in Patients With Rare Diseases: A Population-Based Cohort Study

Background: Orphan drugs are used for the diagnosis, prevention and treatment of rare diseases that, in the European Union, are defined as disorders affecting no more than 5 persons in 10,000. So far, a total of around 800 orphan medicinal products have been approved by the European Medicines Agency, however the utilization profile of orphan drugs has yet to be explored. This study aimed at assessing the utilization profile of orphan drugs authorized for marketing by the Italian Medicines Agency using population-based data. Methods: A total of 21 orphan drugs used in outpatient settings, approved in the European Union before or during the 2008-2018 period and involving 15 rare diseases, were included in the study. The monitored population included patients with one of the conditions surveilled by the population-based Tuscany Registry of Rare Diseases and diagnosed between 2000-2018. A multi-database approach was applied, by linking data from the registry with information collected in drug prescriptions databases. The prevalence and intensity of use were estimated for the selected orphan drugs and other non-orphan medications, used to treat the same rare disease and for which a change in the prevalence of use was hypothesized after authorization of the orphan drug. Results: For some diseases (acquired aplastic anemia, tuberous sclerosis complex, most metabolic diseases) a low prevalence of orphan drugs use was observed (range between 1.1-12.5%). Conversely, orphan drugs were frequently used in hemophilia B, Wilson disease and idiopathic pulmonary fibrosis (maximum of 78.3, 47.6 and 41.8%, respectively). For hemophilia B and Leber's hereditary optic neuropathy, there are currently no other medications used in clinical practice in addition to orphan drugs. Six orphan drugs were used for the treatment of pulmonary arterial hypertension, appearing the elective therapy for this disease, albeit with different utilization profiles (range of prevalence 1.7-55.6%). Conclusion: To the best of our knowledge, this is the first study investigating the utilization profile of orphan drugs prescribed in a defined geographical area, and providing relevant information to monitor over time potential changes in the prevalence of these medications as well as in the health care decision making.

Zinc monotherapy for young patients with oligosymptomatic Wilson disease: A single center, retrospective study

BACKGROUND AND AIMS

Few studies have focused on the treatment failure of zinc monotherapy for oligosymptomatic Wilson disease (WD) patients. Therefore, we aimed to evaluate the long-term efficacy of zinc monotherapy in oligosymptomatic patients and to analyze the possible factors that may influence the outcome of this treatment.

METHODS

We retrospectively reviewed the medical records of oligosymptomatic WD patients who received zinc monotherapy from the time of diagnosis. Then, the characteristics of patients who were treated with zinc monotherapy successfully and those who experienced treatment failure were investigated.

RESULTS

Forty oligosymptomatic WD patients were identified that have received zinc monotherapy as initial treatment, with a median age of 3.83 years at the time of diagnosis. 36 (90%) patients had abnormal alanine transaminase/aspartate transaminase levels at baseline. None of the patients became symptomatic during zinc monotherapy. 28 (70%, Group 1) patients were treated with zinc monotherapy successfully for a median period of 2.4 years. In Group 1, serum aminotransferase levels significantly decreased 6 and 12 months after zinc therapy compared to the baseline levels (P <  0.05). 12 (30%, Group 2) patients experienced treatment failure with zinc monotherapy due to uncontrolled serum liver enzyme levels, and d-penicillamine was combined. The baseline 24-hour urine copper levels before treatment were significantly higher in Group 2 compared to that in Group 1 (182.5 vs 90.92 μg /day, P = 0.018). Comparing the age at onset; ceruloplasmin, serum copper, ALT, and AST levels; and proportions of abdominal ultrasonography abnormality at baseline between Group 1 and 2 revealed no statistically significant differences.

CONCLUSIONS

We found that high initial 24 -h urinary copper levels may lead to treatment failure of zinc monotherapy in oligosymptomatic WD patients. It might be reasonable to follow up liver function tests more closely during zinc monotherapy and to begin combination treatment with chelators early in patients with high level of 24 -h urinary copper.

Wilson's disease- management and long term outcomes

Wilson's disease (WD) is an autosomal recessive genetic disorder of copper metabolism leading to liver or brain injury due to accumulation of copper. Diagnosis is based on: clinical features, biochemical tests including plasma ceruloplasmin concentration, 24h urinary copper excretion, copper content in the liver, and molecular analysis. Pharmacological therapy comprises chelating agents (penicillamine, trientine) and zinc salts which seem to be very effective. Still, poor compliance is a major problem. Adolescents and patients with psychiatric disorders usually have problems with adherence to treatment. As transition is a vulnerable period transition ''training'' should start before the planned transfer, preferably already in early adolescence in cooperation between adult and pediatric clinics. Response to treatment is assessed based on physical examination, normal liver function tests and monitoring of copper metabolism markers. Liver transplantation has a well-defined role in Wilsonian acute hepatic failure according to the prognostic score. The long-term survival in WD patients seems to be very similar as for the general population if disease is early diagnosed and correctly treated. WD patients with a longer delay from diagnosis to therapy and who present with neurological and psychiatric symptoms have worse quality of life.

Combined dimercaptosuccinic acid and zinc treatment in neurological Wilson's disease patients with penicillamine-induced allergy or early neurological deterioration

The clinical data of safety and efficacy of a combined treatment with dimercaptosuccinic acid (DMSA) and Zinc with 2 years’ follow-up in 60 neurological Wilson’s disease (WD) patients was retrospectively analyzed. All the patients included in the present study were newly diagnosed and initialized with D-penicillamine (DPA) treatment but were found to have either neurological deterioration or allergy, and their treatment was switched to a combined treatment of DMSA and Zinc. Fifty-one patients (85%) had the neurological symptoms improved 1 and 2 years after treatment, 7 (11.67%) experienced a stable neurological condition, and 2 (3.33%) suffered deterioration of neurological symptoms. No early neurological deterioration was observed in all patients. Twenty-five percent patients experienced mild adverse reactions which did not require a discontinuation of the DMSA and Zinc treatment. Our study confirmed the safety and efficacy of the combined DMSA and Zinc therapy as an initial and probably long-term treatment in neurological WD patients.

Management of Wilson Disease Diagnosed in Infancy: An Appraisal of Available Experience to Generate Discussion

Increased access to molecular genetic testing is changing the demographics for diagnosing inherited disorders and imposing new challenges for medical management. Wilson disease (WD), typically diagnosed in older children and adults, can now be detected in utero and in infants (children younger than 24 months, including neonates) via genetic testing. An evidence-based approach to management of these neonates and extremely young children, who are typically asymptomatic, has been hampered by lack of clinical experience. We present a case of an infantile diagnosis of WD, review available experience, and discuss current trends in antenatal genetic testing of parents and fetus that may lead to a very early diagnosis of WD. Based on physiological and nutritional considerations, we propose an algorithmic approach to management of infantile WD as a starting point for further discussion. Future collaboration amongst specialists is essential to identify evidence-based approaches and best practice for managing treatment of infants with genetically diagnosed WD.

Recovery of severe acute liver failure without transplantation in patients with Wilson disease

Wilson disease (WD) is a disorder of copper metabolism that leads to liver cirrhosis. WD patients with a NWIS > 11 should receive LT; however, we encountered 2 WD patients with an NWIS > 11 who recovered from ALF without LT. The present report aimed to analyze cases of WD patients with a high NWIS who recovered from severe ALF and to discuss the clinical manifestations of the patients and the effects of treatments, including zinc (Zn) therapy, chelator therapy, PE, CHDF, and LT. We retrospectively evaluated the medical records of five patients (male, 2; female, 3) diagnosed with WD along with severe ALF. In cases 1, 2, and 3, complete recovery from ALF was noted without LT. In case 4, initial recovery from ALF was noted without LT; however, ALF worsened owing to bleeding from the esophageal varix. Thus, the patient eventually needed LT. In case 5, recovery from ALF was noted with LT. All cases, except case 2, showed ALF with maximum PELD/MELD scores ≥26 and NWISs ≥ 11, and had indications for LT. In cases of severe ALF with grade I or II encephalopathy, we recommend evaluations of the effects of Zn and chelator treatments while preparing for LT, as the condition may not improve without LT, and pediatricians or physicians can ask transplant surgeons to perform LT urgently if required.

Chelating principles in Menkes and Wilson diseases: Choosing the right compounds in the right combinations at the right time

Dysregulation of copper homeostasis in humans is primarily found in two genetic diseases of copper transport, Menkes and Wilson diseases, which show symptoms of copper deficiency or overload, respectively. However, both diseases are copper storage disorders despite completely opposite clinical pictures. Clinically, Menkes disease is characterized by copper deficiency secondary to poor loading of copper-requiring enzymes although sufficient body copper. Copper accumulates in non-hepatic tissues, but is deficient in blood, liver, and brain. In contrast, Wilson disease is characterized by symptoms of copper toxicity secondary to accumulation of copper in several organs most notably brain and liver, and a saturated blood copper pool. It is a challenge to correct copper dyshomeostasis in either disease though copper depletion in Menkes disease is most challenging. Both diseases are caused by defective copper export from distinct cells, and we seek to give new angles and guidelines to improve treatment of these two complementary diseases. Therapy of Menkes disease with copper-histidine, thiocarbamate, nitrilotriacetate or lipoic acid is discussed. In Wilson disease combination of a hydrophilic chelator e.g. trientine or dimercaptosuccinate with a brain shuttle e.g. thiomolybdate or lipoate, is discussed. New chelating principles for copper removal or delivery are outlined.

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 Children: A Position Paper by the Hepatology Committee of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition

BACKGROUND

Clinical presentations of Wilson's disease (WD) in childhood ranges from asymptomatic liver disease to cirrhosis or acute liver failure, whereas neurological and psychiatric symptoms are rare. The basic diagnostic approach includes serum ceruloplasmin and 24-hour urinary copper excretion. Final diagnosis of WD can be established using a diagnostic scoring system based on symptoms, biochemical tests assessing copper metabolism, and molecular analysis of mutations in the ATP7B gene. Pharmacological treatment is life-long and aims at removal of copper excess by chelating agents as D-penicillamine, trientine, or inhibition of intestinal copper absorption with zinc salts. Acute liver failure often requires liver transplantation. This publication aims to provide recommendations for diagnosis, treatment, and follow-up of WD in children.

METHODS

Questions addressing the diagnosis, treatment, and follow-up of WD in children were formulated by a core group of ESPGHAN members. A systematic literature search on WD using MEDLINE, EMBASE, Cochrane Database from 1990 to 2016 was performed focusing on prospective and retrospective studies in children. Quality of evidence was assessed according to the GRADE system. Expert opinion supported recommendations where the evidence was regarded as weak. The ESPGHAN core group and ESPGHAN Hepatology Committee members voted on each recommendation, using the nominal voting technique.

Zinc monotherapy for young children with presymptomatic Wilson disease: A multicenter study in Japan

BACKGROUND AND AIM

Few studies of zinc monotherapy for presymptomatic Wilson disease have focused on young children. We therefore evaluated long-term efficacy and safety of zinc monotherapy for such children and established benchmarks for maintenance therapy.

METHODS

We retrospectively and prospectively examined children under 10 years old with presymptomatic Wilson disease who received zinc monotherapy from time of diagnosis at 12 participating pediatric centers in Japan.

RESULTS

Twenty-four patients met entry criteria. Aspartate aminotransferase and alanine aminotransferase decreased significantly beginning 1 month after initiation of treatment and usually remained under 50 U/L from 1 to 8 years of treatment. Twenty four-hour urinary copper decreased significantly at 6 months and usually remained under 75 μg/day and between 1 and 3 μg/kg/day for the remainder of the study. All patients continued to take zinc, and none became symptomatic. In patients under 6 years old who received 50 mg/day of zinc as an initial dose, aspartate aminotransferase and alanine aminotransferase significantly decreased at 1 month after initiation of treatment, as did γ-glutamyltransferase and 24-h urinary copper at 6 months.

CONCLUSIONS

To our knowledge, this is the first multicenter study of zinc monotherapy for young children with presymptomatic Wilson disease. Such monotherapy proved highly effective and safe. Maintaining normal transaminase values (or values under 50 U/L when normalization is difficult) and 24-h urinary copper excretion between 1 and 3 μg/kg/day and under 75 μg/day is a reasonable goal. An initial dose of 50 mg/day is appropriate for patients under 6 years old.

Maintenance zinc therapy after initial penicillamine chelation to treat symptomatic hepatic Wilson's disease in resource constrained setting

BACKGROUND

Experience with zinc in treating symptomatic hepatic Wilson's disease (WD) is limited.

AIM

To study the efficacy of Penicillamine followed by zinc in treating symptomatic hepatic Wilson's disease.

METHODS

We retrospectively analyzed case records of 31 symptomatic hepatic WD patients for whom disease severity scores (Child's, model for end-stage liver disease (MELD), Nazer's, and New Wilson Index (NWI) score) and 24-h urinary copper were compared at 3-time points-baseline at presentation, at transition from penicillamine to zinc and at end of follow up.

RESULTS

Thirty-one patients (median age 11 [5-24] years) with symptomatic hepatic WD were studied; ten had associated neuropsychiatric manifestations of WD. Penicillamine was changed to zinc sulfate either due to financial constraints (28 patients) or due to adverse effects of penicillamine (3 patients). At presentation (baseline), six patients belonged to Child's class A, five to Child's B, and 17 to Child's C. Duration of initial penicillamine chelation therapy was 134 (2-320) weeks, and of subsequent zinc therapy was 363 (35-728) weeks. There was a significant improvement in liver function tests and disease severity scores (Child's, MELD, Nazer's, and NWI score) at the transition from penicillamine to zinc compared to baseline. This improvement was maintained until the end of study period with 90% survival at 10 (2-20) years. Fifteen of the 17 Child's C cirrhotic patients showed significant improvement in disease severity scores from baseline until end of follow up.

CONCLUSIONS

Penicillamine followed by zinc may be a safe and effective treatment in resource-constrained setting for symptomatic hepatic WD patients in all grades of baseline disease severity. Some patients with decompensated cirrhosis due to WD may be managed with medical treatment, avoiding liver transplantation.

Wilson disease in children

Wilson disease (WD) is an inherited disorder mainly of hepatocellular copper disposition, due to dysfunction of the Wilson ATPase, a P_1B-ATPase encoded by the gene ATP7B. In children, as in older age brackets, clinical disease is highly diverse. Although hepatic disease is the common presentation in children/adolescents, neurologic, psychiatric, and hematologic clinical presentations do occur. Very young children may have clinically evident liver disease due to WD. Early diagnosis, preferably when the child/adolescent is asymptomatic, is most likely to result in near-normal longevity with generally good health so long as the patient tolerates effective medication, is adherent to the lifelong treatment regimen, and has consistent access to the medication. Apart from a lively index of clinical suspicion on the part of physicians, biochemical tests including liver tests, serum ceruloplasmin, and basal 24-hour urinary copper excretion and genotype determination are key to diagnosis. Oral chelation treatment remains central to medical management, although zinc appears to be an attractive option for the presymptomatic child. Pediatric patients presenting with Wilsonian fulminant hepatic failure must be differentiated from those with decompensated cirrhosis, since the latter may respond to intensive medical interventions and not require liver transplantation. Recently identified WD-mimic disorders reveal important aspects of WD pathogenesis.

Zinc Therapy for Wilson Disease in Children in French Pediatric Centers

BACKGROUND AND AIMS

Zinc therapy is considered a good option in Wilson disease (WD), as a first-line treatment in presymptomatic children and a maintenance therapy after the initial chelator therapy. The aim of the study was to determine the practical use of zinc treatment in French pediatric centers.

METHODS

A national survey was conducted in the 6 French centers using zinc acetate to treat WD. Clinical and biological parameters, dosage, and outcome were recorded.

RESULTS

A total of 26 children were reported to be treated with zinc acetate, alone or in association with chelators. Of the 9 children (35%) who received zinc alone as a first-line therapy, 2 were switched to D-penicillamine because of inefficacy and 7 remained on zinc alone, but serum transaminase levels normalized in only 4 of them. Five children (19%) were initially treated with zinc in association with D-penicillamine (n = 4) or Trientine (n = 1) with good efficacy. Among the 12 children (46%) who received zinc as a maintenance therapy after D-penicillamine, no relapse of hepatic cytolysis occurred during a median follow-up of 5.2 years, but 2 of them were switched to Trientine because of zinc-related adverse effects. Epigastric pain was observed in 4 children, and a gastric perforation occurred in 1 child.

CONCLUSIONS

The present study demonstrates poor efficacy of zinc as first-line therapy to control liver disease in half presymptomatic children and a high incidence of related gastrointestinal adverse effects in children with WD.

Zinc monotherapy is effective in Wilson's disease patients with mild liver disease diagnosed in childhood: a retrospective study

BACKGROUND

Wilson's disease (WD) evolves rapidly and is fatal if untreated. The treatment of WD patients with mild liver disease is not clearly defined. To address this issue, we evaluated long-term outcomes of three treatment regimens (D-penicillamine, zinc or both) in patients diagnosed in childhood.

METHODS

We retrospectively evaluated efficacy, compliance and reasons for treatment discontinuation in 42 WD patients (median age at diagnosis: 6 years; median follow-up: 12 years) with mild liver disease. Treatment duration for each treatment block until a medication change or completion of follow-up was analyzed. Events of change of treatment were evaluated using Kaplan-Meier analysis.

RESULTS

Total discontinuations due to treatment failure or adverse events were more frequent in patients receiving D-penicillamine (45%) or combination (36%) therapy than in patients receiving zinc (12%) (P = .001 and P = .02, respectively). Treatment failure was more frequent on D-penicillamine (28%) and combination therapy (36%) than on zinc (12%); the difference was statistically significant only between zinc and combination therapy (P = .03). First-line zinc monotherapy controlled WD-related liver disease in 13/15 patients (87%); the two subjects that failed on zinc were poor adherent. Zinc was effective in 3/5 (60%) patients that failed on D-penicillamine and combination regimens. All 15 D-penicillamine responders that switched to zinc had good control of liver disease at a median follow-up of 13.1 years. Among 6 D-penicillamine non-responders that switched to zinc, 4 (67%) responded. At follow-up completion, only 5/42 (12%) patients failed. Adverse event-induced discontinuation was significantly more frequent in patients on D-penicillamine than in patients receiving zinc (P = .03).

CONCLUSIONS

Zinc monotherapy is effective in controlling WD-related liver disease both as first-line and as maintenance treatment in patients with mild liver disease diagnosed in childhood.

Zinc mono-therapy in pre-symptomatic Chinese children with Wilson disease: a single center, retrospective study

Background

There is no official consensus regarding zinc therapy in pre-symptomatic children with Wilson Disease (WD); more data is needed.

Objective

To investigate the safety and efficacy of zinc gluconate therapy for Chinese children with pre-symptomatic WD.

Methods

We retrospectively analyzed pre-symptomatic children receiving zinc gluconate in a single Chinese center specialized in pediatric hepatology. Short-term follow-up data on safety and efficacy were presented, and effects of different zinc dosages were compared.

Results

30 children (21 males) aged 2.7 to 16.8 years were followed for up to 4.4 years; 26 (87%) children had abnormal ALT at baseline. Most patients (73%) received higher than the currently recommended dose of elemental zinc. Zinc gluconate significantly reduced mean ALT (p<0.0001), AST (p<0.0001), GGT (p<0.0001) levels after 1 month, and urinary copper excretion after 6 months (p<0.0054). Mean direct bilirubin levels dropped significantly at 1 month (p = 0.0175), 3 months (p = 0.0010), and 6 months (p = 0.0036). Serum zinc levels gradually increased and reached a significantly higher level after 6 months (p<0.0026), reflecting good compliance with the therapy. Complete blood count parameters did not change throughout the analysis period. 8 children experienced mild and transient gastrointestinal side effects. The higher zinc dose did not affect treatment response and was not associated with different or increased side effects when compared to conventional zinc dose.

Conclusion

In our cohort, zinc gluconate therapy for Chinese children with pre-symptomatic WD was effective, and higher initial dose of elemental zinc had the same level of efficacy as the conventional dose.

Gastrointestinal side effects in children with Wilson's disease treated with zinc sulphate

AIM: To investigate the side effects of a zinc sulphate therapy in a cohort of Polish pediatric patients with Wilson’s disease.

METHODS: We retrospectively analyzed a cohort of 53 pediatric patients with Wilson’s disease treated at the Children’s Memorial Health Institute in Warsaw, Poland between the years 1996 and 2011 with zinc sulphate. Patients were diagnosed with Wilson’s disease according to the scoring system of Ferenci, with 49 cases confirmed by mutation analysis. Data about the dosage scheme of zinc sulphate, side effects and efficacy and toxicity of the treatment were collected and recorded in the patient’s medical chart at each visit to the hospital.

RESULTS: Mean age of diagnosis for the entire cohort was 10 years (range, 2.5-17 years). Duration of treatment with zinc sulfate was 83.3 wk (range, 8-344 wk). Side effects, all of gastrointestinal origin, were observed in 21 patients (40% - 9 males and 12 females), irrespective of the duration of therapy. Thirteen out of 21 patients were over the age of 10 years. The most common ATP7B mutation was p.H1069Q. Esophagogastroduodenoscopy, performed in 7 patients (33.3%) suffering from persistent and severe abdominal pain, revealed gastrointestinal ulcerations or erosions with negative Helicobacter pylori tests in all subjects investigated. The above mentioned 7 patients were treated with proton pump inhibitors. Three of those experienced resolution of symptoms, whereas proton-pump inhibitors failed to alleviate symptoms of the remaining four children and conversion of therapy to D-penicillamine was needed.

CONCLUSION: Zinc sulphate appears to cause significant gastrointestinal side effects, which children on therapy for Wilson’s disease should be closely monitored for.