Oral manifestations of genodermatoses

Oral Mucosa and Nails in Genodermatoses: A Diagnostic Challenge

Genodermatoses represent a group of uncommon, hereditary, single-gene skin disorders, characterized by multisystem involvement, heterogeneous clinical manifestations and different degrees of morbidity and mortality. Some genodermatoses may have oral mucosa and nail involvement, since the oral cavity and cutaneous organ system, including nails, share a close embryologic origin. Nail disorders can manifest with nail hypoplasia or nail hypertrophy. Clinical pictures of affected oral mucosa can be extremely heterogeneous, ranging from asymptomatic papules to painful blisters, leukokeratosis, oral papillomas and fibromas to oral potentially malignant disorders and cancerous lesions. Oral mucosa and nails pathological features may occur synchronously or not and are usually associated with other systemic and skin manifestations. In some cases, oral mucosa and nails diseases may be distinct and constitute the principal sign of the genetic disorder, in other cases they represent only a part of the puzzle for the confirmation of the diagnosis. Continued awareness of the correlation between oral mucosa and nails findings can help physicians to diagnose genodermatosis in a timely manner, allowing more effective clinical management and prevention and/or early detection of complications. This article provides an overview of all specific genodermatoses affecting both oral mucosa and nails. Moreover, the correlation between teeth and nails is summarized in tabular form.

A multistep approach to the diagnosis of rare genodermatoses

Genodermatoses are heritable skin diseases that can cause significant morbidity and mortality. Most of them show characteristic cutaneous findings. Genodermatoses can be associated with extracutaneous system abnormalities. Diagnosing hereditary skin disorders is still a challenging task due to their rarity and diversity, due to diseases evolving over many years, and the initial manifestations not always being diagnostic; therefore, ongoing evaluation and surveillance is often required to make the accurate diagnosis. The algorithm for the diagnosis depends on a combination of thorough clinical and family history clinical examination, laboratory findings, consultation of multiple medical specialists, and molecular analysis. Diagnostic testing targeted at differentiation of similar genodermatoses may be required. Recognition is crucial for the initiation of the treatment for skin manifestations and detection of other extracutaneous abnormalities, including malignancy. Diagnostic accuracy and molecular diagnosis may help in providing a template for ongoing management, testing, and education and prognostication for families of children with genodermatoses.

Genetic and developmental disorders of the oral mucosa: Epidemiology; molecular mechanisms; diagnostic criteria; management

A large number of disorders may affect the oral cavity, including genetic diseases, infections, cancers, blood diseases, skin diseases, endocrine and metabolic disorders, autoimmune and rheumatologic diseases, local lesions, to name a few. Oral mucosa shows a considerable variation in its normal structure and a wide range of conditions may affect it. Such conditions are often harmless or minor and could be primary or secondary to systemic disease. Several of them are quite rare and, hence, the diagnosis is not easy. Clinically, lesions may appear as ulcers, discoloration of the oral mucosa and alterations in size and configuration of oral anatomy. Genetic disorders have specific manifestations and can be caused by a derangement of one or more components of the tissue. Many of them follow the skin or systemic signs of the underlying genetic disease, but in a few cases oral signs could be the first manifestation of the disorder. Among them genodermatoses are prominent. They are inherited disorders characterized by a multisystem involvement. This review describes chondro-ectodermal dysplasia, dyskeratosis congenita, Ehlers-Danlos syndrome, hereditary benign intraepithelial dyskeratosis, keratosis follicularis, lipoid proteinosis, multiple hamartoma syndrome, pachyonychia congenita, Peutz-Jeghers syndrome, tuberous sclerosis and white sponge nevus. Other genetic disorders not included in the genodermatosis group and reported in the present review are: acanthosis nigricans, angio-osteo-hypertrophic syndrome, encephalotrigeminal angiomatosis, familial adenomatous polyposis, focal dermal hypoplasia, focal palmoplantar and oral mucosa hyperkeratosis syndrome, gingival fibromatosis, Maffucci's syndrome, neurofibromatosis (type 1) and oro-facial-digital syndrome (type 1). Disorders during embryonic development might lead to a wide range of abnormalities in the oral cavity; some of them are quite common but of negligible concern, whereas others are rare but serious, affecting not only the oral mucosa, but also other structures of the oral cavity (ie palate, tongue and gingiva). Fordyce's granules, leukoedema, cysts of the oral mucosa in newborns, retrocuspid papilla, geographic tongue, fissured tongue, median rhomboid glossitis, hairy tongue, lingual varices and lingual thyroid nodule are described. This review may help dentists, dental hygienists, but also general internists and pediatricians to diagnose different disorders of the oral mucosa, to understand the pathogenesis and to schedule a treatment plan.

Cowden syndrome: mucocutaneous lesions as precursors of internal malignancy

BACKGROUND

Cowden syndrome is an autosomal-dominant hereditary cancer syndrome with high variability and susceptibility. It is characterized by multiple hamartomas and neoplasms of ectodermal, endodermal and mesodermal origin affecting many organs and also by the increased risk of development of internal malignancies.

CASE REPORT

A 62-year-old woman was referred to our Maxillofacial Unit with a hamartomatous mass of the left lateral tongue which had slowly grown and was obstructing normal speech and restricting oral intake. The patient had a known history of Cowden syndrome and underwent excision of the lesion under general anaesthetic.

DISCUSSION

Orofacial mucocutaneous features are very common in multiple hamartoma and neoplasia syndrome with almost up to 90% of the patients being affected. These cutaneous and mucosal lesions, which are predominantly benign, often manifest prior to the development of the internal malignant tumours associated with the syndrome.

CONCLUSIONS

The prompt identification of Cowden syndrome's plethoric signs and symptoms can lead to appropriate surveillance and multidisciplinary management. Oral manifestations are frequent, prominent and usually precede the establishment of malignant tumours of visceral organs; hence, the maxillofacial surgeon or general dentist may have a significant role in the recognition of the disease. Overall prognosis is dependent on prevention or early treatment of internal malignancies; consequently, early diagnosis together with frequent follow-up forms the cornerstone of management.

Oral vascular malformation in a patient with hereditary hemorrhagic telangiectasia: a case report

Hereditary hemorrhagic telangiectasia (HHT) is an inherited mucocutaneous disease characterized by recurrent epistaxis, lesions on skin and oral mucosa, and arteriovenous malformations of the soft tissues. This article describes the treatment of a 64-year-old woman with a bleeding nodule, which was diagnosed as an arteriovenous malformation of the gingival mucosa. She was treated using sclerotherapy. Patients with HHT can be treated in the dental office and vascular malformations of these patients can be successfully managed with sclerotherapy, which eliminates the need for invasive surgical procedures and the possibility of postsurgical complications.

[Oral manifestations of systemic diseases]

Many systemic diseases may present with oral manifestations and the oral mucosa may act as a mirror of internal involvement. We discuss the most common, specific and unspecific, as the most peculiar oral mucosal manifestations of systemic disease in the different organ systems. The most prevalent conditions of the oral mucosa in the course of HIV infection and marker lesions of multisystemic genodermatoses are elucidated.

Gastrointestinal illnesses and their effects on the oral cavity

Many disease processes affecting the gastrointestinal (GI) tract may cause observable changes to the oral cavity. In fact, oral cavity changes may represent the first clinical manifestation of an underlying GI condition. Recognition and appropriate referral of a possible GI condition contribute to overall health and wellness in patients. Some of the more important GI conditions that may manifest oral cavity involvement include: reflux disorders, inherited GI polyposis syndromes, and inflammatory bowel disease. This article briefly reviews the aforementioned topics.

Tuberous sclerosis complex: advances in diagnosis, genetics, and management

Tuberous sclerosis complex (TSC) is an autosomal dominant multisystem neurocutaneous syndrome characterized by the development of multiple hamartomas distributed throughout the body, skin, brain, heart, kidneys, liver, and lungs. Two-thirds of patients represent sporadic mutations. The classic triad is seizures, mental retardation, and cutaneous angiofibromas. However, the full triad occurs in only 29% of patients; 6% of them lack all three of them. Two tumor suppressor genes responsible for TSC have been identified: TSC1 gene on chromosome 9 and TSC2 on chromosome 16. This article highlights the most recent significant advances in the diagnosis and genetics of TSC, along with a discussion on the limitations and the usefulness of the revised 1998 clinical criteria for the tuberous sclerosis complex. The "ash leaf" macule often comes in other shapes, such as round; most are polygonal, usually 0.5 cm to 2.0 cm in diameter, resembling a thumbprint. Since the death of its describer, Thomas Fitzpatrick, we call each a "Fitzpatrick patch." Special attention is paid in this work to TSC treatment options, including therapeutic trials with rapamycin, also known as sirolimus.

LEARNING OBJECTIVE

After completing this learning activity, participants should familiar with tuberous sclerosis complex, its cutaneous signs and systemic findings stratified by patient age, its genetics, and the potential for meaningful therapeutic intervention.

More than just a bump: the hamartoma syndromes

The hamartoma syndromes detailed in this review are just a few examples of the many genodermatoses now known to be associated with uncontrolled tumor proliferation secondary to mutations in tumor suppressor genes. Knowledge gained through the study of these syndromes has not only improved our understanding of patients afflicted with such conditions, but has also led to significant insight into the important role tumor suppressor genes play in preventing tumor formation and in carcinogenesis. As major strides continue to be made in the identification of causative mutations in the hamartoma syndromes, options for genetic testing will continue to expand. Identification of mutations in PTEN in the various disorders that compose the PTEN hamartoma tumor syndrome illustrates just how such genetic knowledge has altered the way we both categorize and manage certain genetic conditions. As advances continue to be made in this arena, it is quite conceivable that many of the genetic syndromes will be renamed or categorized based on genetic mutations rather than the characteristic clinical features. However, despite these advances, it will still be the astute clinician's recognition of key clinical features that allows the diagnosis of a hamartoma syndrome to be considered.

Hitting the mark in hamartoma syndromes

The missed mark or hamartia underlying each hamartoma syndrome is a mutation in a tumor suppressor gene. This sets the stage for the development of frequent and early tumors in multiple organs. Loss of function of the tumor suppressor in neoplastic cells leads to dysregulation of signaling pathways and tumor growth. The convergence of these signaling pathways to the mTOR pathway suggests that rapamycin or rapamycin-like drugs have potential for treatment, perhaps in combination with drugs targeting other signaling pathways. Haploinsufficient cells also play significant roles in tumor formation. Disrupting interactions between neoplastic cells and surrounding haploinsufficient cells using antiangiogenesis therapies represent an additional approach for treatment. It is hoped that the debilitating effects of these syndromes soon will be alleviated or even reversed though targeted therapies.