Bone mineral density of children with Wilson disease: efficacy of penicillamine and zinc therapy

Metabolic bone disease heralding the diagnosis of Wilson's disease

We report a short-statured, young man in his 20s presenting with bilateral cataract, recurrent kidney stones, history of refractory rickets and bone deformity. He had been consuming calcium and vitamin D supplements and had been operated for cataract and renal stone disease, prior to reporting in our clinic without any significant laboratory or clinical improvement. The patient was diagnosed as having Fanconi's syndrome attributable to Wilson's disease. This patient highlights that in case of resistant rickets, a high index of suspicion must be invoked for Wilson's disease. Timely recognition of this entity results in prompt ministrations and prevention of disability.

The associations between serum trace elements and bone mineral density in children under 3 years of age

We examined the associations of age and serum magnesium, iron, lead, copper, and zinc levels with bone mineral density (BMD) in 2412 children under 3 years of age in order to find a tool to monitor BMD in children without the use of expensive imaging techniques. One-way ANOVA and chi-square tests were used to determine the associations of age and serum trace elements with BMD. Multivariable logistic regression analysis was used to test the correlation of five serum trace elements with BMD after adjustments for potential confounding factors in children under 3 years of age. Significant associations between age and four serum trace elements and BMD were found. Compared to the group with the lowest serum levels detected, the adjusted odds ratio (OR) for the incidence of normal bone mineral density in the third magnesium concentration tertile, the third iron concentration tertile, the fifth copper concentration quintile, the third zinc concentration quintile, and the fifth zinc concentration quintile were 1.30 (95% confidence interval (CI) 1.02–1.67), 1.43 (95% CI 1.11–1.84), 1.42 (95% CI 1.04–1.94), 1.46 (95% CI 1.05–2.04), and 1.48 (95% CI 1.06–2.06), respectively. However, there was no significant correlation between serum lead level and BMD in this study. Age and serum magnesium, iron, copper, and zinc levels are positively associated with BMD in children under 3 years old.

Bone Health in Patients With Liver Diseases

Osteoporosis is the most common bone disease in chronic liver disease (CLD) resulting in frequent fractures and leading to significant morbidity in this population. In addition to patients with cirrhosis and chronic cholestasis, patients with CLD from other etiologies may be affected in the absence of cirrhosis. The mechanism of osteoporosis in CLD varies according to etiology, but in cirrhosis and cholestatic liver disease it is driven primarily by decreased bone formation, which differs from the increased bone resorption seen in postmenopausal osteoporosis. Direct toxic effects from iron and alcohol play a role in hemochromatosis and alcoholic liver disease, respectively. Chronic inflammation also has been proposed to mediate bone disease in viral hepatitis and nonalcoholic fatty liver disease. Treatment trials specific to osteoporosis in CLD are small, confined to primary biliary cholangitis and post-transplant patients, and have not consistently demonstrated a benefit in this population. As it stands, prevention of osteoporosis in CLD relies on the mitigation of risk factors such as smoking and alcohol use, treatment of underlying hypogonadism, and encouraging a healthy diet and weight-bearing exercise. The primary medical intervention for the treatment of osteoporosis in CLD remains bisphosphonates though a benefit in terms of fracture reduction has never been shown. This review outlines what is known regarding the pathogenesis of bone disease in CLD and summarizes current and emerging therapies.

Renal Tubular Function, Bone Health and Body Composition in Wilson's Disease: A Cross-Sectional Study from India

There is limited literature from India with regard to the prevalence and magnitude of renal tubular and bone manifestations in Wilson's disease (WD). Thus, we studied the prevalence of renal tubular acidosis among Indian patients with WD and also evaluated bone health and body composition in them. It was a cross-sectional study conducted at a south Indian tertiary care center. Twenty-five consecutive patients with WD aged more than 12 years attending the hepatology and neurology departments and 50 age, sex and BMI-matched controls were recruited. After clinical assessment, they underwent biochemical testing to assess renal tubular dysfunction. Bone mineral density (BMD) and body composition were assessed using a dual energy X-ray absorptiometry (DXA) scanner. Fifty-six percent (14/25) of patients with WD had renal tubular acidosis (RTA). Of them, 24% were diagnosed to have distal RTA. RTA was more common in hepatic WD patients who had prolonged duration of illness. Patients with WD had significantly lower BMD as compared to control subjects (p < 0.05). Low BMI, low IGF-1 and a shorter duration of therapy were key determinants of low bone mass in them (p < 0.05). Patients with WD had significantly more body fat (p = 0.01) and lower lean muscle mass (p = 0.03) when compared to age, sex and BMI-matched controls. In conclusion, renal tubular acidosis was common in patients with Wilson's disease. These patients had a lower bone mineral density, higher body fat percentage and lower lean muscle mass as compared to controls.

Hepatic Osteodystrophy-Molecular Mechanisms Proposed to Favor Its Development

Almost all patients with chronic liver diseases (CLD) show altered bone metabolism. Depending on the etiology, this manifests in a severe osteoporosis in up to 75% of the affected patients. Due to high prevalence, the generic term hepatic osteodystrophy (HOD) evolved, describing altered bone metabolism, decreased bone mineral density, and deterioration of bone structure in patients with CLD. Once developed, HOD is difficult to treat and increases the risk of fragility fractures. Existing fractures affect the quality of life and, more importantly, long-term prognosis of these patients, which presents with increased mortality. Thus, special care is required to support the healing process. However, for early diagnosis (reduce fracture risk) and development of adequate treatment strategies (support healing of existing fractures), it is essential to understand the underlying mechanisms that link disturbed liver function with this bone phenotype. In the present review, we summarize proposed molecular mechanisms favoring the development of HOD and compromising the healing of associated fractures, including alterations in vitamin D metabolism and action, disbalances in transforming growth factor beta (TGF-β) and bone morphogenetic protein (BMP) signaling with histone deacetylases (HDACs) as secondary regulators, as well as alterations in the receptor activator of nuclear factor kappa B ligand (RANKL)–osteoprotegerin (OPG) system mediated by sclerostin. Based on these mechanisms, we give an overview on the limitations of early diagnosis of HOD with established serum markers.

Wilson's Disease: Clinical Practice Guidelines of the Indian National Association for Study of the Liver, the Indian Society of Pediatric Gastroenterology, Hepatology and Nutrition, and the Movement Disorders Society of India

Clinical practice guidelines for Wilson's disease (WD) have been published by the American Association for the Study of Liver Diseases and European Association for the Study of the Liver in 2008 and 2012, respectively. Their focus was on the hepatic aspects of the disease. Recently, a position paper on pediatric WD was published by the European Society of Pediatric Gastroenterology Hepatology and Nutrition. A need was felt to harmonize guidelines for the hepatic, pediatric, and neurological aspects of the disease and contextualize them to the resource-constrained settings. Therefore, experts from national societies from India representing 3 disciplines, hepatology (Indian National Association for Study of the Liver), pediatric hepatology (Indian Society of Pediatric Gastroenterology, Hepatology and Nutrition), and neurology (Movement Disorders Society of India) got together to evolve fresh guidelines. A literature search on retrospective and prospective studies of WD using MEDLINE (PubMed) was performed. Members voted on each recommendation, using the nominal voting technique. The Grades of Recommendation, Assessment, Development and Evaluation system was used to determine the quality of evidence. Questions related to diagnostic tests, scoring system, and its modification to a version suitable for resource-constrained settings were posed. While ceruloplasmin and 24-h urine copper continue to be important, there is little role of serum copper and penicillamine challenge test in the diagnostic algorithm. A new scoring system - Modified Leipzig score has been suggested with extra points being added for family history and serum ceruloplasmin lower than 5 mg/dl. Liver dry copper estimation and penicillamine challenge test have been removed from the scoring system. Differences in pharmacological approach to neurological and hepatic disease and global monitoring scales have been included. Rising bilirubin and worsening encephalopathy are suggested as indicators predicting need for liver transplant but need to be validated. The clinical practice guidelines provide recommendations for a comprehensive management of WD which will be of value to all specialties.

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.

Osteoporosis and bone mineral density in patients with Wilson's disease: a systematic review and meta-analysis

This systematic review aims to assess the occurrence and risks of osteopenia and osteoporosis in patientswith Wilson's disease (WD). A literature search was conducted utilizing EMBASE and MEDLINE frominception through April 2017. Studies assessing the occurrence or risk of osteopenia and/or osteoporosis inWD patients were included. Effect estimates from the individual study were extracted and combined usingrandom-effect, generic inverse variance method of DerSimonian and Laird. Of 754 studies, four studies with283 WD patients met the eligibility criteria and were included in the data analysis. The pooled prevalencerates of osteopenia and osteoporosis in WD patients were 36.5% (95% confidence interval [CI]: 14.8%-65.7%) and 27.7% (95%CI: 8.6%-60.9%), respectively. When meta-analysis was limited only to adults, the estimated prevalence rates of osteopenia, osteoporosis, and vertebral fracture were 50.0% (95%CI: 42.0%-58.0%), 17.6% (95%CI: 6.7%-38.6%) and 8.01% (95%CI: 4.05%-15.2%), respectively. Meta-regressionshowed significant impacts of age (negative correlation; P=0.002) and male status (positive correlation;P < 0.001) on the prevalence of osteoporosis. The data on risks of osteopenia and osteoporosis in WDpatients were limited. We suggests that there are potential associations of WD with osteopenia and/orosteoporosis. Also, young age and male status are correlated with the higher prevalence of osteoporosis inWD patients.

Other organ involvement and clinical aspects of Wilson disease

Wilson disease (WD) is a rare disorder of copper metabolism that presents mainly with hepatic and neuropsychiatric features. Copper accumulates not only in the liver and brain, but also in other organs. Liver injury can also be the cause of secondary impairment of other tissues. Therefore, the clinical manifestation of WD may be renal, cardiac, skin, osteoarticular, or endocrinologic and include other organ disturbances. Renal abnormalities include tubular dysfunction (e.g., renal tubular acidosis, aminoaciduria) and nephrolithiasis. Bone demineralization is a common manifestation in patients with WD. Cardiac injury may include arrhythmia, cardiomyopathy, and autonomic dysfunction. Different endocrine system manifestations, such as infertility or repeated miscarriages, growth and puberty disturbances, and hypoparathyroidism, are observed. Other important clinical aspects of WD include pancreas involvement, immunologic abnormalities, the presence of lipomas, and skin changes. Although other organ involvement is not common in WD and usually not severe, delayed diagnosis may lead to irreversible changes in organs and tissues. Therefore, awareness of other possible WD presentations is important in the differential diagnosis of WD.

Bone demineralisation in a large cohort of Wilson disease patients

AIMS AND BACKGROUND

We compared the bone mineral density (BMD) of adult Wilson disease (WD) patients (n = 148), with an age- and gender-matched healthy control population (n = 148). Within the WD cohort, correlations of BMD with WD disease parameters, lab results, type of treatment and known osteoporosis risk factors were analysed.

METHODS

Hip and lumbar spine absolute BMD and T-score were measured by dual-energy X-ray absorptiometry. Osteoporosis and osteopenia were defined as a T-score ≤ -2.5, and between -1 and -2.5, respectively.

RESULTS

There were significantly more subjects with abnormal T-scores in the WD population (58.8%) than in the control population (45.3%) (χ(2) = 6.65, df = 2, p = 0.036), as there were 50.0% osteopenic and 8.8% osteoporotic WD patients, vs. 41.2% and 4.1%, respectively, in the controls. Especially L2-L4 spine BMD measurements (BMD and T-scores) differed significantly between the WD population and matched controls. L2-L4 spine BMD for WD patients was on average 0.054 g/cm(2) (5.1%) lower than in matched normal controls (0.995 ± 0.156 vs 1.050 ± 0.135; p = 0.002). We found no significant correlation between BMD values and any of the WD disease parameters (e.g. the severity of liver disease), lab results, type of treatment or known osteoporosis risk factors. Duration of D-penicillamine treatment was negatively correlated with femoral BMD value, but in a clinically irrelevant manner, compared to age and gender. Importantly, BMD remained significantly lower in WD patients (n = 89) vs. controls after excluding WD patients with cirrhosis (p = 0.009).

CONCLUSIONS

Our study suggests that WD is intrinsically associated with bone demineralisation.

Fracture in a Young Male Patient Leading to the Diagnosis of Wilson's Disease: A Case Report

Wilson's disease is a rare genetic disorder that has abnormal copper metabolism. Although the disease's main problems are found in liver and brain, some studies revealed manifestation of various musculoskeletal problems in the patients. In this report, we encountered a young patient who had fracture in the forearm bone. Initially, exception to a previous history of fracture from a motorcycle accident, the patient did not have any medical or drug use history, and laboratory work-ups were insignificant. However, with suspicion on his bone's integrity, bone densitometry was recommended and revealed osteopenic change. To disclose a cause for the change, questions were made to recall any particular history or event, and his complaint of recent vision loss led to ophthalmologic consultation where under slit-lamp test found Kayser-Fleischer ring. Further laboratory work-up found low levels of serum copper and ceruloplasmin and high copper level in 24-hr urine sample that led to the diagnosis of Wilson's disease. Although Wilson's disease has been frequently noticed with considerable musculoskeletal manifestation, it rarity makes the diagnosis illusive to a physician. Hence, despite of its rarity, it is imperative to remember the disease's bony manifestation, and it should be suspected in young patients with demineralized bone when the reason for brittle bone cannot be answered with other better known conditions.

Wilson's disease: An endocrine revelation

Wilson's disease is an inherited disorder of copper metabolism. The affected patients, who otherwise have a near normal life span, may often suffer from some potentially treatable and under recognized endocrine disorders that may hinder their quality of life. We explored previously published literature on the various endocrine aspects of this disease with their probable underlying mechanisms, highlighting the universal need of research in this area.

Bone status and fractures in 85 adults with Wilson's disease

Wilson's disease is characterized by copper deposition, especially in the liver and central nervous system. We assessed the prevalent fractures and bone mineral density (BMD) and related risk factors in 85 patients. BMD was normal, but patients with severe neurological involvement, low BMI, and/or amenorrhea are at risk for fractures.

INTRODUCTION

Wilson's disease (WD) is characterized by copper deposition, especially in the liver and central nervous system. Two studies showed a high prevalence of osteoporosis in WD patients. We wanted to assess the prevalent fractures and bone mineral density (BMD) and to identify risk factors for bone loss and fractures in a large group of WD patients.

METHODS

In this prospective cross-sectional survey at National center of reference for WD, we included 85 patients, 47 women, and 38 men, with a mean age of 35 ± 10 years, and mean time from diagnosis to study of 21 ± 9 years; 57 (67%) patients had neurological signs. Peripheral fractures, prevalent radiological vertebral fractures (VFx), and dual-energy X-ray absorptiometry BMD measurements at the femoral neck (FN) and lumbar spine (LS) were studied.

RESULTS

Mean LS and FN Z-score was normal (-0.37 ± 1.20 at LS and -0.06 ± 1.20 at FN). BMI <19 kg/m(2) and amenorrhea were associated with low BMD. Prevalent peripheral fractures were noted in 43 (51%) and VF in 7 (8%) patients. Severity of neurological involvement and male sex was associated with peripheral fractures, whereas older age, severe neurological involvement, and low BMD and Z-score values were associated with VF.

CONCLUSION

Our data showing normal BMD overall do not support routine bone status evaluation in adults with WD. However, patients with severe neurological involvement, low BMI, and/or amenorrhea are at risk factors for fractures and may require specific monitoring.

Bone mineralization in children with Wilson's disease

BACKGROUND

The goal of this study was to determine bone mineralization in children with Wilson's disease (WD).

METHODS

Twenty-seven patients (16 males) and two age- and gender-matched healthy children for each patient were enrolled in the study. Bone mineral content (BMC, grams) and density (BMD, g/cm(2)) at lumbar 1-4 vertebrae were measured by dual-energy X-ray absorptiometry. Urinary calcium excretion was calculated in 19 patients. The effect of cirrhosis and hypercalciuria on BMC and BMD was also evaluated in WD patients.

RESULTS

There was no statistically significant difference between patients and healthy controls regarding mean BMC (33.0 ± 13.9 vs. 35.8 ± 13.8 g) (p = 0.940) and mean BMD values (0.66 ± 0.16 vs. 0.71 ± 0.18 g/cm(2)) (p = 0.269), respectively. Nine (47.4 %) patients had hypercalciuria. Hypercalciuric patients had statistically significant lower BMC and BMD values than those without hypercalciuria. A significant difference continued to be present after age, weight, height, and pubertal stage adjustment was done, but disappeared after weight, height, follow up duration, and pubertal stage adjustment was done. The presence of cirrhosis did not affect BMC and BMD significantly in WD patients.

CONCLUSIONS

BMC and BMD in children with WD were normal. The presence of hypercalciuria but not cirrhosis may affect BMC and BMD negatively in the patients.

Osteoporosis and fractures in liver disease: Relevance, pathogenesis and therapeutic implications

It is being increasingly recognized that patients with liver disease develop bone loss that can be severe enough to lead to atraumatic fractures and thus markedly diminish life quality and expectancy. The estimated prevalence for liver-related osteoporosis is between 20-420/100000 of the general population, and fractures between 60-880/100000. It should be kept in mind that up to 40% of patients with chronic liver disease may experience a fracture. The pathogenic mediators include fibronectin, insulin like growth factor-I, and various cytokines, but decreased vitamin D and/or treatment with corticosteroids contribute to worsening bone health. Despite the advances in bone biology that have shed some light on the pathogenesis of this bone loss, treatment options remain nonspecific and tightly linked to treatments of other forms of osteoporosis. Thus, treatment should include calcium and vitamin D supplementation in all patients with chronic liver disease. Therapy with bisphosphonates should be considered, especially in patients receiving corticosteroids. This review focuses on the prevalence of this entity as well as the evidence available with regard to the pathogenesis of bone loss in liver disease, the diagnostic steps required in all patients, and the therapeutic options available.

Do children with Wilson's disease have distinct craniofacial morphology? A cephalometric study

OBJECTIVES

Patients with Wilson's disease (WD) develop osseous changes such as osteoporosis, spontaneous fractures, areas of sclerosis and demineralization of maxillary and mandibular bones, and neurologic symptoms including swallowing dysfunctions, which may affect dento-facial growth. However, dento-maxillo-facial structures of these patients have never been investigated. The present study aimed to discover if subjects with WD have different dentofacial structures.

METHODS

Lateral cephalometric films of 13 children (5 males and 8 females) with WD and of 15 normal subjects (6 males and 9 females) were evaluated. Mean ages of the patients and controls were 12.62 ± 3.09 years and 12.01 ± 1.38 years, respectively. Lateral cephalometric cranial films of all subjects were taken in the same cephalostat in a habitual and unstrained body posture. Thirteen linear and 11 angular parameters were measured to describe the craniofacial characteristics of the subjects.

RESULTS

Statistical analysis showed that there is no statistically significant difference between parameters of normal children and children with WD, with the exception of palatal plane inclination. The inclination of palatal plane was higher in children with WD than in normal subjects.

CONCLUSIONS

Children with WD and healthy children have approximately the same dento-maxillo-facial structures. However, increased palatal plane inclination may be a finding of WD.

Wilson's disease

In the almost 100 years since Wilson's description of the illness that now bears his name, tremendous advances have been made in our understanding of this disorder. The genetic basis for Wilson's disease - mutation within the ATP7B gene - has been identified. The pathophysiologic basis for the damage resulting from the inability to excrete copper via the biliary system with its consequent gradual accumulation, first in the liver and ultimately in the brain and other organs and tissues, is now known. This has led to the development of effective diagnostic and treatment modalities that, although they may not eliminate the disorder, do provide the means for efficient diagnosis and effective amelioration if carried out in a dedicated and persistent fashion. Nevertheless, Wilson's disease remains both a diagnostic and treatment challenge for physician and patient. Its protean clinical manifestations make diagnosis difficult. Appropriate diagnostic evaluations to confirm the diagnosis and institute treatment can be confusing. In this chapter, the clinical manifestations, diagnostic evaluation, and treatment approaches for Wilson's disease are discussed.