Dental manifestations of pseudohypoparathyroidism

Dental and craniofacial features associated with GNAS loss of function mutations

BACKGROUND

Pseudohypoparathyroidism (PHP, OMIM #103580) is a very rare disease (incidence 0.3-1/100,000). Heterozygous inactivating mutations involving the maternal GNAS exons 1-13 that encodes the alpha subunit of the stimulatory G protein (Gsα) cause inactivating parathyroid hormone (PTH)/PTHrP signalling disorder type 2 (iPPSD2 or PHP type 1A), which is characterized by Albright hereditary osteodystrophy and resistance to multiple hormones that act through the Gsα signalling pathway (including PTH, thyroid-stimulating hormone, and α-melanocyte-stimulating hormone). To date, little information is available on craniofacial features in patients with PHP. The small number of patients studied in previous reports as well as the lack of molecular characterization of the patients may have precluded the detection of specific orofacial manifestations in the different PHP subtypes.

MATERIALS/METHODS

We conducted a systematic analysis of dental and craniofacial features in 19 patients with iPPSD2 and maternal GNAS inactivating mutations to assess the frequency and specificity of the anomalies.

RESULTS

Facial examinations showed reduced vertical, sagittal, and transverse development of the mid-facial structures. Intraoral and radiographic examinations revealed that 89 per cent of the patients had at least one dental anomaly, including tooth submergence leading to severe infraocclusion in 83 per cent of cases. Craniofacial analysis of lateral cephalometric radiographs also showed a significant alteration in the development of the cranial base and maxillary and mandibular structures in these patients.

CONCLUSIONS

Patients with iPPSD2 and maternal GNAS mutations had specific craniofacial alterations and dental abnormalities. These specific defects should be assessed in order to provide appropriate dental and orthodontic care to these patients. (clinical trial registration: 1920371 v 0, French Nationale Data Processing and Liberties Commission - CNIL).

Recommendations for Diagnosis and Treatment of Pseudohypoparathyroidism and Related Disorders: An Updated Practical Tool for Physicians and Patients

Patients affected by pseudohypoparathyroidism (PHP) or related disorders are characterized by physical findings that may include brachydactyly, a short stature, a stocky build, early-onset obesity, ectopic ossifications, and neurodevelopmental deficits, as well as hormonal resistance most prominently to parathyroid hormone (PTH). In addition to these alterations, patients may develop other hormonal resistances, leading to overt or subclinical hypothyroidism, hypogonadism and growth hormone (GH) deficiency, impaired growth without measurable evidence for hormonal abnormalities, type 2 diabetes, and skeletal issues with potentially severe limitation of mobility. PHP and related disorders are primarily clinical diagnoses. Given the variability of the clinical, radiological, and biochemical presentation, establishment of the molecular diagnosis is of critical importance for patients. It facilitates management, including prevention of complications, screening and treatment of endocrine deficits, supportive measures, and appropriate genetic counselling. Based on the first international consensus statement for these disorders, this article provides an updated and ready-to-use tool to help physicians and patients outlining relevant interventions and their timing. A life-long coordinated and multidisciplinary approach is recommended, starting as far as possible in early infancy and continuing throughout adulthood with an appropriate and timely transition from pediatric to adult care.

Dental anomalies and orthodontic characteristics in patients with pseudohypoparathyroidism

Background

Pseudohypoparathyroidism (PHP) is a rare and inherited disease caused by mutations in the GNAS-gene or upstream of the GNAS complex locus. It is characterized by end-organ resistance to PTH, resulting in hypocalcemia and hyperphosphatemia. We aimed to investigate the dental anomalies according to tooth types and the orthodontic characteristics of patients with PHP.

Methods

Using a cross-sectional design, 29 patients (23 females) with PHP, living in Denmark, were included, and their clinical intraoral photos and radiographs were examined.

Results

Pulp calcification was found in 76% of the patients. Blunting of root apex was present in 55% and shortening of root in 48% of the examined patients. Blunting and shortening of roots were seen more often in premolars than in other tooth types (p_both < 0.01). Crowding of lower anterior teeth was frequently observed (36%) as well as diastema in the upper arch (25%), midline diastema (18%), and Class III malocclusion (11%).

Conclusion

In the present study population, the teeth were frequently affected by pulp calcification and/or deviation of the root morphology. Blunting and shortening of root(s) were more often seen in premolars than in other tooth types. Class III malocclusion was relatively prevalent. It is important to pay attention to dental anomalies and occlusion in order to provide adequate care for patients with PHP.

Cranio-Maxillofacial and Dental Findings in Albright's Hereditary Osteodystrophy and Pseudohypoparathyroidism

INTRODUCTION

The clinical phenotype of pseudohypoparathyroidism (PHP) is caused by Albright's Hereditary Osteodystrophy (AHO). Often, "round face" the only facial clinical sign reported in the literature. The aim of this study was to highlight various cranio-maxillofacial clinical findings associated with AHO.

RESULTS

Four patients presented with PHP type 1a. Only one patient exhibited the classical round face. All patients exhibited dental anomalies, class III malocclusion with maxillary retrusion, and a copper beaten appearance of the skull. One suffered from craniosynostosis.

CONCLUSION

The frequency of craniofacial and dental features associated with malocclusion should prompt careful follow-up, particularly during facial growth, in patients with AHO.

Diagnosis and management of pseudohypoparathyroidism and related disorders: first international Consensus Statement

This Consensus Statement covers recommendations for the diagnosis and management of patients with pseudohypoparathyroidism (PHP) and related disorders, which comprise metabolic disorders characterized by physical findings that variably include short bones, short stature, a stocky build, early-onset obesity and ectopic ossifications, as well as endocrine defects that often include resistance to parathyroid hormone (PTH) and TSH. The presentation and severity of PHP and its related disorders vary between affected individuals with considerable clinical and molecular overlap between the different types. A specific diagnosis is often delayed owing to lack of recognition of the syndrome and associated features. The participants in this Consensus Statement agreed that the diagnosis of PHP should be based on major criteria, including resistance to PTH, ectopic ossifications, brachydactyly and early-onset obesity. The clinical and laboratory diagnosis should be confirmed by a molecular genetic analysis. Patients should be screened at diagnosis and during follow-up for specific features, such as PTH resistance, TSH resistance, growth hormone deficiency, hypogonadism, skeletal deformities, oral health, weight gain, glucose intolerance or type 2 diabetes mellitus, and hypertension, as well as subcutaneous and/or deeper ectopic ossifications and neurocognitive impairment. Overall, a coordinated and multidisciplinary approach from infancy through adulthood, including a transition programme, should help us to improve the care of patients affected by these disorders.

Dental Findings in Patients With Non-surgical Hypoparathyroidism and Pseudohypoparathyroidism: A Systematic Review

Background: Dental aberrations have been mentioned in relation to non-surgical hypoparathyroidism (Ns-HypoPT) and pseudohypoparathyroidism (PHP). However, a systematic review of dental characteristics have not been performed. The present systematic review describes the dental findings in patients with Ns-HypoPT and PHP.

Methods: Studies on Ns-HypoPT and PHP reporting dental features were eligible. A systematic literature search was conducted using four bibliographic databases (Web of Science, Scopus, Pubmed, and Embase) and was limited to studies written in English. Reviews, meta-analyses and letters were excluded. Both the research and reporting of results were based on PRISMA (preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines.

Results: Of 88 studies included, nine were cross-sectional, one was a prospective cohort study, 26 were case series, and 52 were case reports. The most frequently reported findings in patients with Ns-HypoPT were enamel opacities, enamel hypoplasia, hypodontia, and eruption disturbances. In patients with PHP, enamel hypoplasia, eruption disturbance, and deviation of the root morphology were the most frequently reported findings.

Conclusion: An association between enamel hypoplasia and Ns-HypoPT and PHP is likely. The results should, however, be interpreted cautiously due to the limited number of high-quality studies. The present review confirms the need of further well-designed studies, such as large-scale studies, e.g., multicenter studies, to conclude on the reported associations between Ns-HypoPT/PHP and enamel hypoplasia.

[The mouth of patients with hypo- and pseudohypoparathyroidism]

Chronic calcipenia related to hypo- and pseudohypoparathyroidism favors trophic complications, especially expressed on the buccal cavity. Correlated with early onset of the disease and imperfect correction of the metabolic disorders, retardation to appearance and implantation of teeth are observed. The buccal signs often are the most immediately visible expression of the disease. They are painful and disabling. Other acute expressions reflect the neuromuscular hyperexcitability related to tetany. Finally, some etiologies determine specific damage, as in Di George's, HDR syndromes or in Albright's osteodystrophia.

Nonclassic features of pseudohypoparathyroidism type 1A

PURPOSE OF REVIEW

To provide readers with a review of contemporary literature describing the evolving understanding of the pseudohypoparathyroidism type 1A (PHP1A) phenotype.

RECENT FINDINGS

The classic features of PHP1A include multihormone resistance and the Albright Hereditary Osteodystrophy phenotype (round facies, short stature, subcutaneous ossifications, brachydactyly, and early-onset obesity. Obesity may be because of a decrease in resting energy expenditure because most patients do not report significant hyperphagia. Patients with PHP1A have an increased risk of type 2 diabetes. In addition to brachydactyly and short stature, orthopedic complications can include spinal stenosis and carpal tunnel syndrome. Hearing loss, both sensorineural and conductive, has been reported in PHP1A. In addition, ear-nose-throat findings include decreased olfaction and frequent otitis media requiring tympanostomy tubes. Sleep apnea was shown to be 4.4-fold more common in children with PHP1A compared with other obese children; furthermore, asthma-like symptoms have been reported. These new findings are likely multifactorial and further research is needed to better understand these nonclassic features of PHP1A.

SUMMARY

Along with the Albright Hereditary Osteodystrophy phenotype and hormone resistance, patients with PHP1A may have additional skeletal, metabolic, ear-nose-throat, and pulmonary complications. Understanding these nonclassic features will help improve clinical care of patients with PHP1A.

"Pitted" lesions in dermatology

Cutaneous pitting, dimpling, or depressions are frequently dealt with in clinical practice. Such lesions may be primary manifestations of a disorder or develop as secondary changes during the course of the disease. Cutaneous pitting may be a manifestation of certain genodermatoses and internal disorders when it serves as a marker of such conditions. This article describes various types of pitted lesions affecting the ectodermal structures (skin, nails, and teeth) and their clinical significance along with brief description of the associated conditions.

Effect of high phosphorus diet on tooth microstructure of rodent incisors

Enamel hypoplasia and disruption of dentinogenesis are the most common abnormalities of development and mineralization of human teeth. Several reports are available in the literature on the influence of dietary calcium on the formation of human and rodent tooth; however, the information about the influence of dietary phosphorus on the tooth formation is scarce. The aim of the present investigation was to examine the chronic effect of high phosphorus diet and improper dietary calcium to phosphorus ratio on the mandibular incisor microstructure in a hystricomorph rodent--Octodon degu--using macroscopic observation, histopathological examination, transmission and scanning electron microscopy. The present study shows that enamel and dentin development is disturbed under high phosphorus diet and improper calcium to phosphorus ratio. Disturbed mineral metabolism resulted in enamel depigmentation, enamel hypoplasia, enamel pitting and altered dentin morphology. The results suggest that more attention should be focused on dietary phosphorus content when facing altered tooth structure in young patients with deciduous or permanent dentition. Furthermore, we showed that degus can be used as an experimental animal model for the study of the developmental teeth disturbances.

Clinical diagnosis of enamel defects: pitfalls and practical guidelines

Changes in enamel during its development are permanently recorded, and commonly present as either demarcated opacity, diffuse opacity, or enamel hypoplasia. Developmental enamel defects may provide clues regarding their aetiology, and this may have application in clinical dentistry, dental epidemiology and anthropology. However, the usefulness of these applications may be hampered by many pitfalls encountered in the detection and diagnosis of developmental enamel defects. The defects may be masked by saliva, dental plaque, and incorrect lighting. In addition, confounding effects of post-eruptive changes such as dental caries, attrition, and traumatic loss of tooth structure may impair the detection of developmental enamel defects. The non-specificity of appearance of enamel defects may make aetiologic diagnosis of enamel hypoplasia difficult. Furthermore, difficulty is often encountered in the relative timing of events in enamel hypoplasia, due to limited data on the chronology of development of the human dentition. In this review, pitfalls in the clinical assessment of enamel defects are discussed, and guidelines to overcome some of these difficulties are presented.

Enamel hypoplasia, bilateral cataracts, and aqueductal stenosis: a new syndrome?

We report on a 12-year-old girl who presented with generalized enamel hypoplasia, cataracts, and enlargement of the cerebral ventricles secondary to aqueductal stenosis. Previously described syndromes of enamel defects with or without cataracts were excluded on the basis of clinical criteria and appearance of the dentition. Metabolic conditions which could have caused cataracts were excluded clinically and by biochemical tests. The combination of signs in this patient may represent a new syndrome.

Albright's hereditary osteodystrophy

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Imprinting in Albright's hereditary osteodystrophy

Review of published reports of Albright's hereditary osteodystrophy (AHO) involving two or more generations shows a marked excess of maternal transmission. Full expression of the gene (AHO + hormone resistance, pseudohypoparathyroidism) occurs in maternally transmitted cases and partial expression (AHO alone) when the gene is inherited from the father, suggesting the involvement of genomic imprinting in the expression of this disorder.

Pseudohypoparathyroidism, parkinsonism syndrome, with no basal ganglia calcification

A 20 year old woman with pseudohypoparathyroidism, Parkinsonism and no basal ganglia calcifications shown by computed tomography is reported. She has typical features of pseudohypoparathyroidism and biochemical evidence of end-organ resistance to parathyroid hormone. She is mentally retarded and has tremor, rigidity, bradykinesia, and stooped posture. The cause of Parkinsonism in pseudohypoparathyroidism is thought to be basal ganglia calcification. This patient must have another pathophysiology, perhaps directly related to a G protein defect, causing impaired neurotransmission.

Nature and frequency of dental changes in idiopathic hypoparathyroidism and pseudohypoparathyroidism

Eleven patients with idiopathic hypoparathyroidism and pseudohypoparathyroidism were examined orally and medically. All patients had a history of tetanic and/or epileptic manifestations. Correspondingly, disturbances in the metabolism of calcium and phosphorus had been present in all. Dental anomalies were demonstrated in all patients but one. Enamel hypoplasia was observed in six cases, disturbances in tooth eruption in eight, root defects in five and hypodontia in seven. Dental anomalies were more frequent than could be expected from the literature, probably because the dental aspects of hypoparathyroid disease often have been overlooked. In the present material, the above-mentioned disturbances were most severe and frequent in the pseudohypoparathyroid group. Hypoparathyroid conditions are highly invalidating, easily accessible to treatment, but often undiagnosed for years. Therefore, the dental observation of severe disturbances in tooth formation and eruption pattern may be of crucial importance and should lead to further medical investigation.