Osteopathia striata, osteopetrosis, and impaired hearing. A case report

Rare Diseases of the Middle Ear and Lateral Skull Base

Otalgia, otorrhea and hearing loss are the most common ear-related symptoms that lead to the consultation of an otolaryngologist. Furthermore, balance disorders and affections of the cranial nerve function may play a role in the consultation. In large academic centres, but also in primary care, the identification of rare diseases of the middle ear and the lateral skull base is essential, as these diseases often require interdisciplinary approaches to establish the correct diagnosis and to initiate safe and adequate treatments. This review provides an overview of rare bone, neoplastic, haematological, autoimmunological and infectious disorders as well as malformations that may manifest in the middle ear and the lateral skull base. Knowledge of rare disorders is an essential factor ensuring the quality of patient care, in particular surgical procedures. Notably, in untypical, complicated, and prolonged disease courses, rare differential diagnoses need to be considered.

Osteopathia striata with cranial sclerosis, Wilms’ tumor and the WTX gene

Osteopathia striata with cranial sclerosis (OSCS, OMIM#300373) is an X-linked dominant sclerosing bone dysplasia that shows a distinct phenotype in females and males. In 2009, Zandra Jenkins et al found that germline mutations in the FAM123B/WTX/AMER1 gene, mapped to chromosome Xq11.2, cause both the familial and sporadic forms of OSCS. Intriguingly, the WTX gene was already known as a putative tumor suppressor gene, since in 2007 Rivera et al had reported inactivating WTX mutations in Wilms’ tumor (WT), the most frequent renal tumor of childhood. Here we review the heterogeneous clinical presentation of OSCS patients and the involvement of WTX anomalies in OSCS and in WT.

WTX R353X mutation in a family with osteopathia striata and cranial sclerosis (OS-CS): case report and literature review of the disease clinical, genetic and radiological features

Osteopathia striata with cranial sclerosis (OS-CS) or Horan-Beighton syndrome is a rare X-linked dominant inherited bone dysplasia, characterized by longitudinal striations of long bones and cranial sclerosis. Patients can be asymptomatic or present with typical facial dysmorphism, sensory defects, internal organs anomalies, growth and mental retardation, depending on the severity of the disease. WTX gene (Xq11) has been recently identified as the disease causing gene. Aim of this article is to present the case of a 6 year old girl initially evaluated for bilateral hearing loss. Patient's head CT scan pointed out sclerosis of skull base and mastoid cells, and abnormal middle-ear ossification. Clinical examination of the patient and her mother were suspicious for OS-CS. The diagnosis was confirmed by X-rays examination showing typical longitudinal striation. Genetic analysis allowed the identification of maternally transmitted heterozygous nonsense c.1057C>T (p.R353X) WTX gene mutation. We also provide a systematic review of currently available knowledge about clinical, radiologic and genetic features typical of the OS-CS.

When bone becomes marble: Head and neck manifestations of osteopetrosis

Osteopetrosis is a genetically determined bone disease resulting from malfunction of osteoclastic activity, leading to excessive deposition of immature bone. This may result in complete agenesis of the paranasal sinuses, oral complications and multiple cranial neuropathies. The case of a 12-year-old boy with osteopetrosis is presented.

Surgically assisted rapid maxillary expansion in two cases of osteopathia striata with cranial sclerosis

Osteopathia striata with cranial sclerosis (OS-CS) is a rare skeletal dysplasia characterized by linear striations of the long bones, osteosclerosis of the cranium, and extraskeletal anomalies. Osteosclerosis of the cranial and facial bones can lead to disfigurement and to disability due to the pressure on the cranial nerves. We report two cases of OS-CS where surgically assisted rapid maxillary expansion was performed for widening the extremely narrow maxilla. One should be aware of the disease-related problems and the possible complications that might occur with this type of patient.

Osteopathia striata with cranial sclerosis and hearing loss

Osteopathia striata is a manifestation of several bone dysplasias. In association with cranial sclerosis, it represents a separate entity that is not limited to the bones, but may also affect other structures, leading to an abnormal face, cleft palate, deafness, heart defects and vertebral anomalies. Neurological findings range from normal development to marked retardation with hydrocephalus, cranial nerve deficiencies and deafness. So far, only a few patients have been described in the literature, demonstrating autosomal dominant inheritance. Here, we report a spontaneous mutation of inheritance. The parents and three sisters of the affected child are healthy. In 78.6% of the reported cases with osteopathia striata and hearing loss, a conductive hearing loss was described. Surgical attempts to mobilize the middle-ear bones were unsuccessful because of swelling and augmented growth of the bones in the middle ears. Here the mobilization of the eardrum was not attempted because the middle ear cavities were epidermized. This is the second case in the literature in which a myringotomy was not done because the middle ear was completely epidermized. As a possible alternative, children with osteopathia striata and cranial sclerosis with hearing loss should be fitted with hearing aids because surgery of the middle ear probably will be difficult or perhaps not possible.

Osteopathia striata with cranial sclerosis

Osteopathia striata with cranial sclerosis (OS-CS) is a specific bone dysplasia manifested by hypertelorism, flat nasal bridge, frontal bossing, large head, hypoplastic maxilla, palate anomalies, chronic otitis media, hearing deficits, nasal obstruction, and neurological changes of deafness, facial palsy, ophthalmoplegia, and mental retardation. We will review the clinical and radiologic findings in a new patient from birth to 20 years; this is believed to be the thirty-fifth patient reported. OS-CS is 2.5 times more common in females and occurs as an autosomal dominant condition or a sporadic dominant mutation with patients presenting for evaluation from the newborn period to the fifth decade. Skeletal abnormalities are distinctive including sclerosis of the skull base and calvarium, linear striated densities in the long bones and pelvis, and poor development of the mastoid and sinus air cells. Radionuclide bone scans with SPECT indicated in our patient increased bone turnover which was supported by biochemical findings of increased pyridinoline excretion. The major complications are due to constriction of essential foramina at the skull base. The condition is not life-threatening but can produce disability.

Osteopathia striata with cranial sclerosis: variable expressivity in a four generation pedigree

Osteopathia striata is a manifestation of several bone dysplasias. In association with cranial sclerosis it represents a separate entity, which is not limited to the bones but may affect other structures, leading to abnormal face, cleft palate, deafness, heart defects, and vertebral anomalies. Neurological findings range from normal development to marked retardation with hydrocephalus, cranial nerve deficiencies and deafness. Ten families, including our own, clearly demonstrate autosomal dominant inheritance with female preponderance and great inter- and intrafamilial variability.

Osteopathia striata, short stature, cataracts, and microdontia: a new syndrome? A case report

A case of osteopathia striata, childhood cataracts, short stature, elbow deformity, and microdontia with rhizomicry in a white male is reported. The report includes a detailed analysis of dental changes. The relationship of this syndrome to other similar conditions including osteopathia striata with cranial base sclerosis and Rothmund-Thomson syndrome are discussed.

Sclerosing bone dysplasias--a target-site approach

Sclerosing bone dysplasias are a poorly understood group of developmental anomalies, much of whose etiology is still obscure. The list of conditions constituting this group is relatively short: osteopetrosis (Albers-Schönberg disease), pycnodysostosis (Maroteaux-Lamy disease), enostosis (bone island), osteopoikilosis, osteopathia striata (Voorhoeve disease), progressive diaphyseal dysplasia (Camurati-Engelmann disease), hereditary multiple diaphyseal sclerosis (Ribbing disease), four types of endosteal hyperostosis (van Buchem disease, Worth disease, Nakamura disease, and Truswell-Hansen disease), dysosteosclerosis, metaphyseal dysplasia (Pyle's disease), craniometaphyseal dysplasia, melorheostosis (Leri disease), and craniodiaphyseal dysplasia. There are instances in which two or more of the above disorders coexist. These are termed "overlap syndromes", most commonly involving osteopathia striata, osteopoikilosis, and melorheostosis. A classification of these dysplasias is elaborated based on a targetsite approach that views them as disturbances in development associated with the processes of either endochondral or intramembranous bone formation, or both. Accumulated evidence suggests that many of these disorders stem from common defects in bone resorption and/or formation during the processes of skeletal maturation and modeling. Finally, the subgroup of overlap syndromes is emphasized as indicating a strong interrelationship between the sclerosing dysplasias of bone, with perhaps a common pathogenesis for many.

Osteopetrosis (marble bone disease)--agenesis of paranasal sinuses

A case of Osteopetrosis (Marble Bone Disease) in a child is presented. Agenesis (non-pneumatization) of all paranasal sinuses has been one of the salient features in this case.

Optic nerve decompression in osteopetrosis

Osteopetrosis is a rare disorder characterized by generalized increased skeletal density with abnormalities of bone modeling. The skull base is usually involved. Loss of vision with optic nerve atrophy is the most common neurological finding and is traditionally believed to be the result of optic nerve compression within the compromised optic canal. However, retinal degeneration has recently been described and is hypothesized to be the etiology of the visual loss (thus challenging the value of surgical decompression). The authors report their experience with six children suffering from osteopetrosis and severe visual loss. All six patients underwent bilateral microsurgical optic nerve decompression through a supraorbital craniotomy. Improvement in visual acuity occurred postoperatively in five patients, and none had complications. Two technical points are emphasized: 1) optic nerve decompression should be wide and include not only unroofing of the canal but also drilling along both sides of the optic nerve, and 2) the thick, irregular, and highly domed orbital roof should be smoothed down by high-speed drilling to facilitate surgical exposure with minimal retraction of the frontal lobe.

Osteopathia striata, cranial sclerosis with cleft palate and facial nerve palsy

Osteopathia striata (OS) is a rare bone dysplasia characterized by longitudinal sclerotic striations of the long bones. It is of no clinical importance, but OS associated with cranial sclerosis represents a separate entity with a high incidence of palatine malformations and deafness. Only 19 cases of this entity have been reported in the literature. One patient of this series also had facial nerve paralysis. This paper presents a second case of OS, cranial sclerosis, palatine pathology and recurrent facial nerve paralysis. This incidence of 2/20 (10%) does not seem to be coincidental but raises the possibility that facial nerve palsy is one of the clinical manifestations of this specific bone abnormality.

Osteopathia striata with cranial sclerosis. Report of a case and review of the literature

This article describes a case of osteopathia striata with cranial sclerosis. The patient also has multiple sclerosis. The symptomatology includes a right sided conduction deafness and a left maxillar nerve deficit, which were both attributed to the bone disorder. The authors review the literature of this rare genetic syndrome and pay special attention to the neurological manifestations. These mainly consist of hearing loss, mental subnormality and occasionally the involvement of other cranial nerves. The bone scan in their patient shows hyperactivity in the left skull base region. This finding provides further evidence that, at least in some instances, the bone disorder has a progressive course.

Mixed-sclerosing-bone-dystrophy: report of a case and review of the literature

We present clinical, laboratory, radiologic, genetic, and pathologic findings in a 49-year-old man with mixed-sclerosing-bone-dystrophy (MSBD), review the six cases previously reported as "MSBD", and examine the nosology of this rare bone dysplasia. Our asymptomatic patient showed radiographic changes consistent with osteopoikilosis, osteopathia striata, and melorheostosis and had widespread osteosclerosis of the axial skeleton. Several previous reports of combined osteosclerotic disorders suggest the latter finding represents osteopetrosis, however, histologic examination of our patient's iliac crest excluded that diagnosis. Limited radiographic surveys of his eight children were unremarkable except for isolated bone islands in two sons. Literature review revealed that "MSBD" has actually been used generically to describe the association of a variety of osteosclerotic bone dysplasias when they occur together in a single patient.

Osteopathia striata with cranial sclerosis: Highly variable expression within a family including cleft palate in two neonatal cases

Cranial sclerosis with osteopathia striata was diagnosed in four members of a family in three generations. The expression of the gene varied from mild cranial enlargement to cranial abnormality associated with severe Pierre-Robin triad. The disorder was diagnosed prenatally in the most severely affected member of the family from the finding of an increased biparietal diameter of the fetal head on ultrasound examination.

Osseous changes of osteopathia striata associated with cranial sclerosis. An autosomal dominant entity

Association of cranial sclerosis with mixed osteopathia striata is a rate combination which has been proved recently to be an autosomal dominant entity. The present case, apparently sporadic in the kindred, records a further example of this association in a 27-year-old asymptomatic male.

Osteopathia striata associated with familial dermopathy and white forelock: evidence for postnatal development of osteopathia striata

Osteopathia striata and a macular, hyperpigmented dermopathy were found in a Caucasian woman and her two daughters. Sequential radiographs in one daughter showed that the bone lesions were not present during infancy but developed during early childhood. The skin lesions were not those most often associated with osteopathia striata, but appeared tgo be a unique dermatosis, which also included a hypopigmented forelock. A son had neither osseous nor ectodermal lesions. These abnormalities appear to represent a new syndrome, which is inherited with X-linked or autosomal dominant transmission.

Head and neck manifestations of malignant osteopetrosis

Malignant osteopetrosis is the autosomal recessive form of osteopetrosis. Besides anemia, hepatosplenomegaly, and the osteopetrotic bone seen on roentgenogram, the head and neck manifestations are important to the diagnosis and clinical course of this disease. Eye, ear, nose, face, teeth, mandible, maxilla, central nervous system structures, and cranial nerves are often involved.

Osteopathia striata with cranial sclerosis. An autosomal dominant entity

The syndromic association of striae in the long bones and pelvis, together with sclerosis of the base of the skull, has been investigated in four families. Impairment of hearing and alteration in the shape of the head are the most important clinical manifestations. Spinal abnormalities are an inconsistent feature. The distribution of affected individuals in the kindreds is compatible with autosomal dominant inheritance.

A review of the osteopetroses

The osteopetroses are a group of conditions which are characterized by varying combinations of bony sclerosis and modelling defects. Classical osteopetrosis may be inherited as an autosomal dominant or autosomal recessive: the former variety is benign, heterogeneous and comparatively common, while the latter is precocious, potentially lethal and rare. Many other craniotubular dysplasias and hyperostoses are loosely grouped with the osteopetroses. The commonest of these is the autosomal dominant form of craniometaphyseal dysplasia, while the others which are well known include Pyle disease, and van Buchem disease. Sclerosteosis is a progressive condition in which massive cranial thickening is associated with syndactyly and gigantism. Each of these disorders has specific clinical and radiographic features, which permit recognition. Diagnostic accuracy is crucial for treatment, prognostication and effective genetic management.

Temporal bone histopathology of osteopetrosis

The histopathology of the temporal bone of an eight and one-half-year-old girl with osteopetrosis (Albers-Schönberg disease) was studied to evaluate the pathogenesis of its frequent complications in hearing and facial nerve function. The patient was blind and had acute otitis media, but facial paralysis was not noted. Although the size of the temporal bone pyramid was markedly increased due to enormously thickened periosteal layer, changes in the endosteal and endochondral layers were less marked. Exostotic growth of periosteal bone was seen in the middle ear wall, and the tympanic cavity appeared to be narrowed. At the oval window region, the facial nerve was pushed down towards the stapes due to extreme overgrowth of periosteal bone of the epitympanum, and the superstructure of the stapes was imbedded deeply into the dislocated facial nerve and had strongly compressed it. Although the footplate was free from ankylosis, the crus of the stapes appeared to be immobilized because it was lodged in the facial nerve. Such changes appeared to be the pathogenesis of one form of facial nerve paralysis and conductive hearing loss associated with osteopetrosis.

Osteopetrosis associated with familial paraplegia: report of a family

A clinical analysis of three members of a family with documented osteopetrosis and familial paraplegia is presented. All patients had a long history of increased bone density and slowly progressing paraparesis of both legs. A thorough review of the literature has revealed no other cases which presented with paraplegia without spinal cord compression. Although the etiologic factor or factors remain unknown, our review supports the contention that this is a distinct clinical entity.