A novel approach in diagnosing multiple dentigerous cysts using CBCT illustration indicative of Mucopolysaccharidosis VI - a case report.

Mucopolysaccharidosis VI is a genetic disorder affecting multiple organs with sundry clinical presentations. The main etiological factor reflects the disturbances in mucopolysaccharide metabolism leading to deposition of acid mucopolysaccharide in various tissues. The pathognomonic features of the disease include a large head, short neck, corneal opacity, open mouth associated with an enlarged tongue, enlargement of the skull, and long anteroposterior dimension with unerupted dentition, dentigerous cyst-like follicles, condylar defects, and gingival hyperplasia. An 18-year-old boy with Maroteaux-Lamy syndrome (mucopolysaccharidosis type VI) is described in this article, emphasizing the oral manifestations and radiographic illustration of lesions in the jaws. It also emphasizes the essential role of cone-beam computed tomography to identify and analyze multicentric pathologies in the jaws.

Delayed Onset Post-Operative Neurologic Deficit in a Patient With Mucopolysaccharidosis type VI: A Case Report.

Background: Mucopolysaccharidoses (MPS) are lysosomal storage disorders characterized by abnormal deposition of glycosaminoglycans (GAGs) in tissues. In type VI MPS, otherwise known as Maroteaux-Lamy syndrome, the defect is in the enzyme N-acetylgalactosamine-4-sulfatase. Thoracolumbar kyphosis results from GAG deposition, leading to incompetence of posterior ligamentous structures as well as poor trunk control. Though neurologic symptoms from canal compression due to deformity and hypertrophy of tissues have been described, occasionally requiring surgical decompression, there has not been a prior report of late onset of symptoms in a previously neurologically intact patient following surgery to correct spine deformity. Methods: The case reviewed is a 14 year old girl with mucopolysaccharidosis type VI underwent anterior release and posterior instrumentation for correction of severe progressive lumbar kyphosis. Postoperatively she developed delayed onset of profound lower extremity weakness and underwent urgent wide laminectomies and resection of thickened ligamentum flavum. At 1 year follow-up, she had near complete neurologic recovery. Conclusion: Patients with mucopolysacchari-doses are at significant risk for neurologic compromise both as part of the natural history of the disease, and as a risk of deformity correction. The surgeon must consider the pathologic thickening of tissues surrounding the spinal cord when planning surgery. Level of Evidence: IV.

Double valve replacement in a patient with Maroteaux - Lamy syndrome as an ultimate team challenge.

BACKGROUND: The Maroteaux-Lamy syndrome (Mucopolysaccharidosis type VI) is a rare, inherited metabolic disease that results in progressive tissue accumulation of dermatan-sulfated glycosaminoglycans and inflammatory consequences that almost always affects the heart valves. From the anesthesia point of view, managing the airway and ventilation might be a serious challenge due to specific features of the syndrome. Additionally, it is more than probable that the surgical team will perform a non-straightforward procedure. CASE PRESENTATION: A 42-year-old male with Maroteaux-Lamy syndrome was referred to our department with shortness of breath, due to severe aortic stenosis, and at least moderate mitral valve regurgitation. The patient was initially scheduled for aortic valve replacement. After multiple attempts with video assisted laryngoscopy, the endotracheal intubation was achieved with the aid of fiberoptic bronchoscopy, while the ventilation succeeded only with laryngeal mask. The somatic features of the syndrome that made the anesthesia induction extremely difficult, also affected the surgical procedure. Suboptimal exposure of the mitral valve, patch enlargement of the aortic root to host the bigger possible prosthesis, and the hard decision to replace the mitral valve even with a marginal indication were the intraoperative challenges for the surgical team. Finally, the patient underwent a successful double valve replacement with aortic root enlargement and 18 months postoperatively remains improved. CONCLUSION: Patients with Maroteaux-Lamy syndrome represent a challenge for both anesthesiologists and cardiac surgeons. The whole team should be well prepared to deal with difficulties in airway management, ventilation and surgical valve exposure. The cardiac surgeon should be ready to offer additional procedures and even replace "prematurely" a moderately diseased valve in order to avoid a dangerous reoperation. The limited knowledge on the natural history of the Maroteaux-Lamy syndrome valvulopathy and the difficulties in anesthesia induction support this approach.

Ovarian Mucinous Carcinoma in a Pediatric Patient With Maroteaux-Lamy Syndrome.

Mucopolysaccharidoses (MPS) are autosomal recessive lysosomal storage disorder (LSD). Mucinous ovarian cancer is a rare tumor and seldom encounters among adolescents. Here we describe an adolescent female with MPS type VI diagnosed with mucinous ovarian cancer. To our knowledge, this is the first case report of ovarian mucinous carcinoma in a patient with MPS. The association between MPS and cancer has never been described so far, but some LSD are known to have an increased risk of malignancies. The pathogenetic link between LSD and cancer is not well understood. Several potential mechanisms have been proposed for pathogenesis, which include chronic inflammation, abnormal function of activated macrophages, and genetic modifiers. Further studies are required, to understand the role of LSD in cancer.

Otorhinolaryngological manifestations in 61 patients with mucopolysaccharidosis.

OBJECTIVES: The mucopolysaccharidoses (MPS) are inherited lysosomal storage disorders with multisystemic and highly variable clinical manifestation. ENT symptoms are common and early signs of MPS. The most common ENT diagnoses are chronic/recurrent rhinosinusitis, acute otitis media, otitis media with effusion, hearing loss and airway obstruction. METHODS: A single-centre retrospective chart review of 61 patients (36 M/25F) with different MPS subtypes (MPS I (n = 15), MPS II (n = 10), MPS III (n = 17), MPS IV (n = 15) and MPS VI (n = 4)) was conducted. The age of ENT presentation and frequency of ENT symptoms, surgeries and their distribution among MPS subtypes was studied. The relationship between ENT presentation, first ENT surgery and the age of diagnosis was also evaluated. RESULTS: Median age at the first ENT manifestation was 2.8 years, median age at MPS diagnosis 4.1 years. The great majority of patients (90%) manifested at least one ENT diagnosis; often before the diagnosis of MPS (75%). Chronic/recurrent rhinosinusitis was the most prevalent ENT diagnosis (77%), followed by upper airway obstruction (65%) and hearing loss (53%). Chronic/recurrent rhinosinusitis was the first ENT symptom to appear (median age 2.2 years), followed by otitis media with effusion (3.7 years) and hearing loss (4.5 years). At least one ENT surgery was performed in 57% of patients; in 69% before MPS diagnosis was established. Median age of the first ENT surgery was 4.1 years. ENT symptoms and surgical procedures were earliest present in MPS II. CONCLUSIONS: Our study documents high and early occurrence of various otolaryngologic symptoms in MPS and thus highlights the role of ENT specialist in prompt diagnosis of these rare diseases and their long-term management.

Maroteaux-Lamy syndrome: a rare and challenging case of mitral valve replacement.

Maroteaux-Lamy syndrome is a very rare multisystem disorder. Cardiac valve surgery is common in these patients who present a unique set of perioperative and intraoperative challenges to the surgeon and treating team. We describe successful mitral valve replacement using an inverted aortic prosthesis in a 29-year-old lady with Maroteaux-Lamy syndrome, with a good result at 10 months.

Evaluation of spinal involvement in children with mucopolysaccharidosis VI: the role of MRI.

OBJECTIVE: To evaluate spinal MRI features of mucopolysaccharidosis (MPS) VI and to assess the correlation with clinical findings. METHODS: We retrospectively evaluated spinal MRI scans and clinical findings at the time of imaging in 14 patients (8 male, 6 female) with MPS VI. Craniometric measurements were performed and the images were assessed for bony anomalies, spinal stenosis and spinal cord compression. The degree of cervical cord compression was scored and correlated with neurological examination findings at the time of imaging. Vertebral alignment, structural changes in spinal ligaments and intervertebral discs were also assessed. RESULTS: All patients had cervical stenosis due to bony stenosis and thickened retrodental tissue (median: 6.05 mm, range 3.3-8 mm). Retrodental tissue thickness was found to increase with age (p = 0.042). Compressive myelopathy was detected at upper cervical level in 11 (79%) and lower thoracic level in 2 patients (14%). Significant inverse correlation was found between cervical myelopathy scores and neurological strength scores. The most common bony changes were hypo/dysplastic odontoid; cervical platyspondyly with anterior inferior beaking; thoracic posterior end plate depressions and lumbar posterior scalloping. Kyphosis due to retrolisthesis of the beaked lumbar vertebrae and acute sacrococcygeal angulations were other remarkable findings. CONCLUSION: MRI is an essential component in evaluation of spinal involvement in MPS VI, and scanning of the entire spine is recommended to rule out thoracic cord compression. Advances in knowledge: This study provides a detailed description of spinal MRI findings in MPS VI and underlines the role of MRI in management of cord compression.

Atypical Presentation of Acute Angle-Closure Glaucoma in Maroteaux-Lamy Mucopolysaccharidosis with Patent Prophylactic Laser Peripheral Iridotomy: A Case Report.

INTRODUCTION: Maroteaux-Lamy syndrome (MLS) is a rare progressive condition characterized by inflammation and scarring of multiple organs. Ocular complications caused by anterior segment abnormalities commonly cause visual impairment in MLS. Angle-closure glaucoma is one such complication, but there are limited data on presentation, workup, and management of this condition. CASE PRESENTATION: This case report describes an atypical presentation of acute angle-closure glaucoma in a patient with MLS despite a prior prophylactic laser peripheral iridotomy-which would typically prevent an acute angle-closure attack-that was patent and intact at the time of angle closure. DISCUSSION: Because of severe congenital anterior segment crowding, high axial hyperopia, and constant accommodative demand in patients with MLS, we recommend performing two prophylactic laser peripheral iridotomies simultaneously in the same eye instead of one. The mechanism for this indication differs from that in patients at risk of acute angle-closure glaucoma because of lens zonulopathy alone. We hope that this case report may help prevent vision loss and optimize quality of life in patients with MLS who may be wheelchair-bound but are typically high functioning with normal intelligence.

A long term follow-up study of the development of hip disease in Mucopolysaccharidosis type VI.

Hip problems in Mucopolysaccharidosis type VI (MPS VI) lead to severe disability. Lack of data on the course of hip disease in MPS VI make decisions regarding necessity, timing and type of surgical intervention difficult. We therefore studied the development of hip pathology in MPS VI patients over time. Data were collected as part of a prospective follow-up study. Standardized supine AP pelvis and frog leg lateral radiographs of both hips were performed yearly or every 2years. Image assessment was performed quantitatively (angle measurements) and qualitatively (hip morphology). Clinical burden of hip disease was evaluated by physical examination, six minute walking test (6MWT) and a questionnaire assessing pain, wheelchair-dependency and walking distance. A total of 157 pelvic radiographs of 14 ERT treated MPS VI patients were evaluated. Age at first image ranged from 2.0 to 21.1years. Median follow up duration was 6.8years. In all patients, even in the youngest, the acetabulum and os ilium were dysplastic. Coverage of the femoral head by the acetabulum improved over time, but remained insufficient. While the femoral head appeared normal in the radiographs at young age, the ossification pattern became abnormal in all patients over time. In all patients the distance covered in the 6MWT was reduced (median Z scores -3.3). Twelve patients had a waddling gait. Four patients were partially wheelchair-dependent and ten patients had limitations in their maximum walking distance. In conclusion, clinically significant hip abnormalities develop in all MPS VI patients from very early in life, starting with deformities of the os ilium and acetabulum. Femoral head abnormalities occur later, most likely due to altered mechanical forces in combination with epiphyseal abnormalities due to glycosaminoglycan storage. The final shape and angle of the femoral head differs significantly between individual MPS VI patients and is difficult to predict.

Aortic and Mitral Valve Involvement in Maroteaux-Lamy Syndrome VI: Surgical Implications in the Enzyme Replacement Therapy Era.

Open-heart operations in patients with mucopolysaccharidoses are exceedingly rare and pose distinct clinical challenges. Few reports exist of valve replacement in type VI mucopolysaccharidosis, mostly entailing combined mitral and aortic valve replacement. Here reported is the case of a young woman with mitral and aortic valve disease, in whom the surgical procedure was confined to the aortic valve. The rationale behind this strategy, particularly in light of the benefits offered by specific enzyme replacement therapy of type VI mucopolysaccharidosis, is discussed.

Advantages of early replacement therapy for mucopolysaccharidosis type VI: echocardiographic follow-up of siblings.

Mucopolysaccharidosis type VI (Marateaux-Lamy syndrome) is an autosomal recessive disorder caused by deficient activity of the enzyme N-acetylgalactosamine-4-sulphatase (arylsulphatase B). Cytoplasmic vacuoles full of dermatan sulphate are observed in endothelial cells, myocyte, and fibroblasts, compromising the function of cardiovascular structures and contributing significantly towards morbidity and mortality. The primary objective of this study was to assess the advantages of early replacement therapy with recombinant human arylsulphatase B through the echocardiographic follow-up of sisters who started treatment at quite different ages: one at 9 years and the other at 1 year and 7 months. The older sibling showed striking mitral and aortic valve compromise when she was only 2 years old and finally needed cardiac surgery at the age of 8, even before starting enzyme replacement. Differently, the younger one has developed only mild mitral and aortic lesions throughout the follow-up period of 3 years. The two siblings had left ventricle cardiomyopathy, but partial reverse remodelling was induced by enzyme replacement therapy in both cases. The younger sibling has never received any cardiovascular drugs, whereas the older one has been using ß-blockers and diuretics in addition to enzyme therapy to cope with heart failure. Comparing the outcomes of these two sisters with a very aggressive phenotype of mucopolysaccharidosis type VI, the conclusion was that early onset of therapy may slow down the disease progression and prevent severe cardiac lesions to be established. Moreover, patients' compliance is essential for the success of treatment, as sequential echocardiographic evaluation demonstrated worsening of some cardiac lesions whenever infusions were missed.

Craniocervical decompression in patients with mucopolysaccharidosis VI: development of a scoring system to determine indication and outcome of surgery.

OBJECTIVE: To analyse diagnostic value of somato-sensory evoked potentials (SEP), magnetic resonance imaging (MRI), and clinical neurological examination in the decision for decompression surgery in mucopolysaccharidosis (MPS) VI patients with craniocervical cord compression (CCJ). METHODS: We retrospectively analysed neurological examination, SEP of the median nerve and MRI outcomes from 31 MPS VI patients. Individual scores for each test (based on severity of findings) and a sum of scores of all three procedures (CCJ score) were evaluated for their potential to measure the need for and improvement after surgery. Differences between rapidly and slowly progressive patients were also evaluated. RESULTS: Fourteen patients (45 %) aged 4-34 years underwent decompression surgery. Median age at first operation was lower in rapidly than in slowly progressive patients (12 vs. 24 years; P = 0.008). Neurological and SEP findings but not MRI results differed significantly between non-operated and operated patients (P < 0.001, P = 0.003 and P = 0.08, respectively). A significant relationship was found between MRI and clinical neurological examination (P < 0.001) and between SEP and clinical neurological examination (P = 0.01) but not between MRI and SEP (P = 0.06). The CCJ score discriminated between operated and non-operated patients (4-9 points vs. 0-3 points; P < 0.001) and decreased in 61.5 % of patients after surgery. CONCLUSIONS: CCJ is common in rapidly and slowly progressive MPS VI patients. The CCJ score is an objective and transparent tool for assessing pathology of the CCJ, the need for surgery, and improvement after surgery.

Spinal cord compression in Maroteaux-Lamy syndrome: case report and review of the literature with effects of enzyme replacement therapy.

UNLABELLED: The purpose of this report is to review the literature regarding spinal cord compression in mucopolysaccharidosis type VI (MPS VI), to discuss the possible impact of enzyme replacement therapy (ERT) and to stress the necessity of timely surgical intervention. A 9.5-year-old female patient with severe MPS VI had been receiving ERT since the age of 7. After 2.5 years of treatment, she developed craniovertebral canal stenosis with spinal cord compression and cervical myelopathy. CONCLUSIONS: (1) baseline cervical spine evaluation and regular neurological assessment should be performed in all MPS VI patients, (2) detailed neurological observation should be conducted in patients treated with ERT, especially in the period of improvement in the osteoarticular system, as ERT fails to prevent cervical myelopathy and (3) surgical decompression is required and in order to achieve a satisfying outcome it might be crucial to perform surgery at an early age.

A multinational, multidisciplinary consensus for the diagnosis and management of spinal cord compression among patients with mucopolysaccharidosis VI.

Cervical cord compression is a sequela of mucopolysaccharidosis VI, a rare lysosomal storage disorder, and has devastating consequences. An international panel of orthopedic surgeons, neurosurgeons, anesthesiologists, neuroradiologists, metabolic pediatricians, and geneticists pooled their clinical expertise to codify recommendations for diagnosing, monitoring, and managing cervical cord compression; for surgical intervention criteria; and for best airway management practices during imaging or anesthesia. The recommendations offer ideal best practices but also attempt to recognize the worldwide spectrum of resource availability. Functional assessments and clinical neurological examinations remain the cornerstone for identification of early signs of myelopathy, but magnetic resonance imaging is the gold standard for identification of cervical cord compression. Difficult airways of MPS VI patients complicate the anesthetic and, thus, the surgical management of cervical cord compression. All patients with MPS VI require expert airway management during any surgical procedure. Neurophysiological monitoring of the MPS VI patient during complex spine or head and neck surgery is considered standard practice but should also be considered for other procedures performed with the patient under general anesthesia, depending on the length and type of the procedure. Surgical interventions may include cervical decompression, stabilization, or both. Specific techniques vary widely among surgeons. The onset, presentation, and rate of progression of cervical cord compression vary among patients with MPS VI. The availability of medical resources, the expertise and experience of members of the treatment team, and the standard treatment practices vary among centers of expertise. Referral to specialized, experienced MPS treatment centers should be considered for high-risk patients and those requiring complex procedures. Therefore, the key to optimal patient care is to implement best practices through meaningful communication among treatment team members at each center and among MPS VI specialists worldwide.

Manifestações cardíacas em pacientes com mucopolissacaridose VI / Cardiac manifestations in patients with mucopolysaccharidosis VI

A mucopolissacaridose tipo VI (MPS VI) é uma doença rara causada pela deficiência da enzima lisossômica arilsulfatase B, com consequente acúmulo de glicosaminoglicanos (GAGs) em vários tecidos, incluindo o cardiovascular. Com o objetivo de descrever as manifestações cardiovasculares na MPS VI, uma das principais causas de óbito, seis pacientes (4 a 13 anos) foram avaliados por exame físico, eletrocardiograma e ecocardiograma. Todos os pacientes, exceto a paciente com a menor idade, apresentaram sopro cardíaco e alterações ecocardiográficas. Os 6/6 pacientes apresentaram, no eletrocardiograma, desvio do eixo cardíaco para a direita, associado à sobrecarga atrial esquerda (1/6) ou distúrbio de condução (1/6).

Clinical outcomes following hematopoietic stem cell transplantation for the treatment of mucopolysaccharidosis VI.

Mucopolysaccharidosis VI (MPS VI, Maroteaux-Lamy Syndrome) is one of approximately 50 known lysosomal storage disorders. MPS VI is characterized by an absence or deficiency of N-acetylgalactosamine 4-sulfatase (arylsulfatase B) resulting in accumulation of dermatan sulfate. Prior to the availability of enzyme replacement therapy (ERT), the clinical management of MPS VI was limited to supportive care and allogeneic hematopoietic stem cell transplantation (HSCT); however, due to the rarity of this disease, little is known about the long-term outcomes of HSCT for MPS VI. The following retrospective study was performed using aggregate data gathered by the Center for International Blood and Marrow Transplant Research (CIBMTR) between 1982 and 2007 to determine survival probability for patients with MPS VI following allogeneic HSCT. This analysis identified 45 MPS VI patients with a median age of 5 years (range, 1-22 years) at the time they received an allogeneic HSCT. Cumulative incidence (95% CI) of acute graft-vs.-host disease at 100 days was 36% (21-53%). Probability of survival was 78% (65-89%) at 100 days and 66% (52-79%) at 1 and 3 years. While these data are based upon small numbers of recipients, they represent the largest series to date and may help clinicians assess the relative risks and benefits of currently available therapies.

Maroteaux-Lamy syndrome: orofacial features after treatment by bone marrow transplant.

PURPOSE: The objective of the present study was to emphasise the oral and dental findings of a male patient with the Maroteaux-Lamy syndrome who successfully underwent bone marrow transplantation (BMT) at the age of 22 months. CASE REPORT: A 15-year-old boy was referred to the Dentistry Division of the Catholic University of Brasília, Brazil, for dental diagnosis. General characteristics of the Maroteaux-Lamy syndrome, such as a large head, a short neck, corneal opacity, an open mouth with macroglossia, enlargement of the skull and a long anteroposterior dimension, were observed. The patient had received the benefit of a BMT at an early stage. Therefore, characteristics were presented in a moderate form, except for the skeletal symptoms. DISCUSSION: Maroteaux-Lamy syndrome, also known as mucopolysaccharidosis type VI, is a lysosomal storage disorder that is caused by a deficiency of arylsulphatase B, which leads to an accumulation of dermatan sulphate in tissues and its increased excretion in urine. The deposition of mucopolysaccharides leads to a progressive disorder involving multiple organs. It is a rare condition that is inherited as an autosomal recessive trait. The characteristic features of this disease include retardation in growth, a large head, a short neck, corneal opacity, typical facies and spinal abnormalities. The main dental findings of this syndrome include gingival hyperplasia, hypertrophy of the maxillary alveolar ridge, macroglossia, unerupted dentition, malocclusions and dentigerous cyst-like follicles. BMT is a therapeutic treatment that is given to permanently replace any disorder caused due to the deficiency of enzymes in patients with storage diseases.

Lentiviral-mediated correction of MPS VI cells and gene transfer to joint tissues.

Joint disease in mucopolysaccharidosis type VI (MPS VI) remains difficult to treat despite the success of enzyme replacement therapy in treating other symptoms. In this study, the efficacy of a lentiviral vector to transduce joint tissues and express N-acetylgalactosamine-4-sulphatase (4S), the enzyme deficient in MPS VI, was evaluated in vitro and the expression of beta-galactosidase was used to evaluate transduction in vivo. High viral copy number was achieved in MPS VI fibroblasts and 4-sulphatase activity reached 12 times the normal level. Storage of accumulated glycosaminoglycan was reduced in a dose dependent manner in both MPS VI skin fibroblasts and chondrocytes. Enzyme expression was maintained in skin fibroblasts for up to 41 days. Comparison of two promoters; the murine phosphoglycerate kinase gene promoter (pgk) and the myeloproliferative sarcoma virus long terminal repeat promoter (mpsv), demonstrated a higher level of marker gene expression driven by the mpsv promoter in both chondrocytes and synoviocytes in vitro. When injected into the rat knee, the expression of beta-galactosidase from the mpsv promoter was widespread across the synovial membrane and the fascia covering the cruciate ligaments and meniscus. No transduction of chondrocytes or ligament cells was observed. Transduction was maintained for at least 8 weeks after injection. These results indicate that the lentiviral vector can be used to deliver 4S to a range of joint tissues in vitro and efficiently transduce synovial cells and express beta-galactosidase in vivo.

Mucopolissacaridose tipo VI (síndrome de Maroteaux-Lamy): avaliação da mobilidade articular e das forças de garra e de pinça / Mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome): assessment of joint mobility and grip and pinch strength

OBJETIVO: Descrever o perfil de mobilidade articular e das forças de garra e de pinça de indivíduos com MPS VI, além de sua correlação com a excreção urinária de glicosaminoglicanos, atividade da ARSB e distância percorrida no teste de caminhada de 6 minutos. MÉTODOS: Estudo observacional de 28 pacientes com MPS VI, não submetidos a tratamento específico. Todos os pacientes foram avaliados em relação à amplitude da mobilidade articular, forças de garra e de pinça, excreção urinária de glicosaminoglicanos, atividade da ARSB e teste de caminhada de 6 minutos. RESULTADOS: Demonstrou-se maior comprometimento de flexão de ombro, sem correlação com a idade, e da extensão de joelho e flexão de cotovelo, estas últimas correlacionadas negativamente com a idade. A força de garra mostrou-se comprometida em todos os pacientes, e a força de pinça apresentou correlação positiva com idade. CONCLUSÕES: A restrição da flexão de ombro, sem correlação com a idade, sugere que este achado esteja presente precocemente na MPS VI e se constitua em sinal clínico importante para suspeita diagnóstica desta doença. A amplitude da extensão de joelho e da flexão de cotovelo, por sua vez, por apresentarem correlação negativa com a idade, são possíveis marcadores da evolução da doença. Estudos adicionais são necessários para confirmação dessas hipóteses.

OBJECTIVE: To describe the profile of joint mobility and grip and pinch strength of MPS VI patients and to correlate this with urinary excretion of glycosaminoglycans (GAGs), ARSB activity, and the distance covered in a 6-minute walking test (6MWT). METHODS: This was an observational study of 28 patients with MPS VI, who had not undergone specific treatment. All patients were assessed for amplitude of joint mobility (shoulder, elbow, and knee), grip and pinch strength and urinary GAG excretion and also performed the 6MWT. RESULTS: Shoulder flexion exhibited the greatest limitation, with no correlation with age, followed by knee extension and elbow flexion, both of which were correlated inversely with age. Hand grip strength was compromised in all patients, and pinch strength exhibited a positive correlation with age. CONCLUSIONS: The fact that restricted shoulder flexion was not correlated with age suggests that this finding is present early on in MPS VI and that it constitutes an important clinical sign that should arouse diagnostic suspicion of this disease. The amplitude of knee extension and elbow flexion, in turn, are possible markers of disease progression since they have a negative correlation with age. Further studies are needed to confirm these hypotheses.

The oral manifestations of Maroteaux-Lamy syndrome (mucopolysaccharidosis VI): a case report.

Maroteaux-Lamy syndrome is one of the genetic disorders involving disturbances in mucopolysaccharide metabolism resulting in increased storage of acid mucopolysaccharide in various tissues. The basic defect in Maroteaux-Lamy syndrome is a deficiency of arylsulfatase B, which leads to accumulation of dermatan sulfate in tissues and their urinary excretion. The deposition of mucopolysaccharides leads to a progressive disorder involving multiple organs that often results in death in the second decade of life. This disease, which has several oral and dental manifestations, is first diagnosed on the basis of clinical findings. A large head, short neck, corneal opacity, open mouth associated with an enlarged tongue, enlargement of skull, and a long antero-posterior dimension are the main characteristic features. Dental complications can be severe and include unerupted dentition, dentigerous cystlike follicles, malocclusions, condylar defects, and gingival hyperplasia. An 11-year-old boy with Maroteaux-Lamy syndrome (mucopolysaccharidosis type VI) is described in this article, with special emphasis on the oral manifestations.