Hurler's syndrome: dental findings in a case treated with bone marrow transplantation in infancy

Abstract

Hurler's syndrome, also known as mucopolysaccharidosis I (MPS I-H), is a rare condition inherited as an autosomal recessive trait. It is caused by a deficiency in alpha-L-iduronidase, an enzyme that participates in the degradation of the glycosaminoglycans (GAGs) heparin sulphate and dermatan sulphate. Children with Hurler's syndrome appear nearly normal at birth but, left untreated, show a progressive mental and physical deterioration caused by a build-up of GAGs in all organs of the body. Death is often caused by cardiac or respiratory failure and usually occurs before the second decade of life. In recent years, bone marrow transplantation (BMT) has been employed in the management of patients with Hurler's syndrome. However, the dental findings observed in these cases have not previously been reported in the dental literature. Here we report a patient aged 11 years and 6 months, presented to a Specialist Paediatric Dentistry Unit, who was successfully treated by BMT at 18 months of age.

Oral manifestations in children with mucopolysaccharidosis

“…Open bite and crossbite are explained by the presence of macroglossia and reverse swallowing. 7,9,14,19,22,24,27,30 Similar results were reported in the study by Antunes et al, 9 in which five participants in a total of twelve patients showed limitation of mouth opening. This limitation may be due to the presence of condylar defects.…”

“…This limitation may be due to the presence of condylar defects. 7,9,14,[19][20][21][22]24,25,27,28,30 Our study found that 75% patients with MPS had a higher incidence of bleeding gums in over 30% of the tooth surfaces, corroborating the marginal gingivitis previously described in MPS patients associated with a poor oral hygiene and limited manual dexterity. [7][8][9]13,19,[21][22][23][24] These findings are possibly related with tissue changes that occur in mucopolysaccharidosis, but also with other factors including difficulty in maintaining oral hygiene, lack of brushing techniques, poor attendance to dentist and lack of collaboration.…”

“…7,9,[13][14][15][20][21][22][23][24][26][27][28][29] The macroglossia is due to the deposition of glycosaminoglycans (GAG) in the tongue structure that usually results in an anterior open bite. 7,9,13,15,[19][20][21][22][23][24][25][26][27][28]30,31 The higher prevalence of lingual interposition in patients with MPS may be due to the presence of macroglossia, anterior open bite and strong maxillary compression. 14 Similarly Turra et al 14 report the presence of lingual interposition in thirty-four participants of their study, being more frequent in the type VI.…”

Genetic Disorders Associated with Gingival Enlargement

“…Hurler syndrome (Mucopolysaccharidosis IH, OMIM #607014, Gene Map locus 4p16.3) is an autosomal recessive disorder caused by a mutation in the gene encoding for the enzyme alpha-L-iduronidase leading to deficiency of the enzyme and accumulation of glycosaminoglycans (heparan sulphate and dermatan sulphate) in various tissues (Hingston et al, 2006). Hurler sundrome is characterized by mental retardation, dwarfism, coarse facial features, flexion contractures, hepatosplenomegaly, hernias, corneal clouding (Leroy & Croeker, 1966;McKusick et al, 1965), respiratory infections and cardiac complications (Mckusick &Neufeld, 1983).…”

Hurler Syndrome

“…The inability to degrade these macromolecules, results in their storage in a variety of tissues including the liver, spleen, heart, connective tissue and others, resulting in premature death, usually by second decade of life. Hurler syndrome represents the classical prototype of a mucopolysaccharide disorder, with a very low prevalence of 1:100,000 births and no predilection for sex and ethnicity has been found 2,3 . The diagnosis is usually made between the age of 6 and 24 months with evidence of coarse facial features, prominent forehead with large tongue, hepatosplenomegaly, corneal cloudiness, skeletal deformities, joint stiffness, short stature, acquired cardiomyopathy and progressive lenticular enlargement with increased intracranial pressure caused by communicating hydrocephalus.…”