Mucopolisaccaridose type 2 – Hunter syndrome is a recessive genetic disease with X-chromosome autosomal transmission – it mainly affects male gender. The scope of the paper is to describe the abnormalities encountered in the Type 2 Mucopolisaccaridose – Hunter Syndrome. Material and method. The clinical case of a patient aged 7 years and 4 months diagnosed with Mucopolisaccaridose type 2 – Hunter’s Syndrome at 2 years of age is reported, which claims severe functional disorders due to problems in the oral cavity. Results and discussions. Severe disorders have resulted in physiognomic dysfunction, for which the patient has sought dental care. The main issue is the optimization of the masticatory function, which can be solved at this age through the treatment of the extensive carious processes, which will also solve the phonation disorder, and then the growth process will be closely monitored, intervening with other treatment solutions after the end of this process. Conclusions. Early dental consultations, parents’ awareness of the importance of periodic controls to ensure the dental health of the current teeth, the monitoring of the growth process, as well as a multidisciplinary approach are the desiderata for the treatment of children with Hunter’s Syndrome.
Key-words: Mucopolisaccaridose type 2, Hunter Syndrome, monogenic genetic disease, dental anomalies, macroglossia.
Mucopolisaccaridose tip 2 – Hunter Syndrome (CIM10-E76.1(2-214); OMIM 309900 – is a monogenic genetic disease, with recessive transmission by chromosome X – affecting especially subjects of male gender.
Cytogenic analysis shows that the mutation occurs at Xq28 level. This gene under normal conditions encodes iduronate-2-sulfatase synthesis. This enzyme competitively binds protein glycosaminoglycans to form a complex structure called proteoglycans. They are part of the basic substance of connective tissue.
The disease has general affection, acting where there is conjugated tissue .
The incidence is 1/100,000 newborns.
Prenatal diagnosis can be performed consisting of the dose of iduronate-2-sulfatase synthesis in amniotic villi taken by amniocentesis.
The Laboratory diagnosis is supported by urine dosing of glycosaminoglycans having increased values and iduronate-2-sulfatase synthesis enzyme in leukocytes, where it should have low values for diagnosis purposes.
The survival duration is reduced for those with severe forms of the disease – who survive a maximum of 15 years. In exchange, subjects with average disease forms can survive 30-40 years. (5,6)
The clinical image is composed of the following: the first clinical signs occur between 2-4 years and consist of the progressive loss of neurological procurements . Within a short while, deafness can occur. The face is grotesque, the skin is thick, rough and the joints of the subject hurt.
The child has hepatospenomegaly, structural hypotrophy. Affected individuals rarely exceed 150 cm. Nanism is evident after the second year of life .
The mouth is thick, resilient, delayed tooth eruption, sprained teeth and vicious inserts.
Treatment  is a symptomatic one, aimed at alleviating the disease and trying to maintain the overall health.
At the oral cavity level, it is advisable to maintain the integrity of the teeth by proper hygiene and to periodically check with the pediatrician and orthodontist.
The patient, who is 7 years and 4 months old, male gender, weighing 16 kg, coming from the urban area – a Bucharest neighbourhood area, who appeared in a private office to solve functional disorders starting from the oral cavity.
From the anamnesis, it results that the patient was diagnosed at the age of 2 years of age with Mucopolisaccaridose-type 2 (Hunter’s disease) following an admission to a paediatric hospital in Bucharest. Also, from the hereditary-collateral antecedents, this genetic disease is present also at his 4-year-old sister. At the time of the last hospitalization, marked weight hypotrophy and moderate hepatosplenomegaly were detected.
The general clinical examination found the following: weight 16 kg. (at the time of the study), facial dysmorphism, larger ears, low oral commissures, moderate hepatosplenomegaly. The diagnosis of Mucopolisaccaridose has been confirmed by the administration of iduronate-2-sulfatase in fibroblasts and leukocytes.
The exobucal examination reveals pale teguments.
Facial Examination: It reveals a facies with oral commissures oriented downwards with microstromia and macroglossia.
Functional exam: reveals functional disorders of mastication, occlusion, swallowing and physiognomy.
At the oral cavity level, the patient has the following dental status, with temporary teeth. There is a mismatch between its chronological age and dental age.
The carious activity is increased. The patient presents cavity processes at its level: 55, 54, 53, 52, 51, 61, 62, 63, 64, 65, 75, 73, 83 and radicular debris at: 74, 84 and 85. The presence of processes including areas resistant to caries is worth noting. Dentin from carious processes is light brown and has a tough consistency (img. 1.a and img. 1.b).
The occlusion is open due to the increased macroglossia, which has also caused the difficulty of swallowing.
The gingival mucosa is red, inflamed, bleeding both on touching and spontaneously.
Problems at the oral cavity level have contributed to the establishment of functional disorders requiring correction using a complex, individualized treatment based on the growth stage. The patient and the parents were trained on the importance of oral hygiene and the performance of correct brushing.
After performing prophylactic training, carious lesions were treated. At the same time were recommended deconditioning exercises for the deconditioning of infantile swallowing and oral respiration. An E.N.T. examination for the removal of nasal polyps has been recommended as beneficial for correct diagnosis and effective recovery of affected functions of the oral and maxillary apparatus.
Results and discussions.
Being a genetic monogenic disease with recessive autosomal transmission through chromosome X that specifically affects male gender , the diagnosis of genetic syndrome was early on at the age of 2 years, although the first visit to the dentist was performed relatively late, when parents have experienced functional disorders.
From a dental point of view, the patient presented dental eruptions with numerous atypical caries similar to those described in the specialty literature.
The impairment of masticatory and phoning functions was determined by open occlusion and obvious macroglossia which was accentuated by infantile swallowing of the subject.
The main problem was the collaboration with the minor patient to optimize the masticatory function, possibly resolved at this age primarily by treatment of the extensive carious processor, which partially solved also the phonation disorder, and they are to closely monitor the growth process and intervene with other treatment solutions after the end of this process.
Early dental consultations, parents’ awareness of the importance of periodic controls to ensure the dental health of the current teeth, the follow-up of the growth process and a multidisciplinary approach are decisive desiderates in the treatment of children with Mucopolisaccaridose tip 2 (Hunter Syndrome).
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