Partial Albinism and Deaf Mutism

The Tietz syndrome associated with cardiac malformation: a case report with literature review

Background

Tietz syndrome is a very rare clinical entity characterized by the association of profound bilateral congenital sensorineural deafness and generalized hypopigmentation of skin, eyes, and integuments (snow white appearance). It is an autosomal dominant syndrome due to a mutation in the melanocyte inducing transcription factor (MITF) gene. The association of a heart malformation has never been reported in this syndrome.

Case presentation

We report two cases of two cousins aged 5 years and 20 months respectively with a history of first degree consanguineous parents. Both girls presented with diffuse hypopigmentation of the skin, blond hair, blue eyes, and bilateral diffuse retinal hypopigmentation at ocular fundus exam. Bilateral profound sensorineural hearing loss was confirmed by auditory brainstem response in both cases. Echocardiography revealed a cardiac malformation such as interventricular communication in the older cousin and interatrial communication in the younger cousin. The family investigation did not reveal a similar case among ancestors. The diagnosis of Tietz syndrome was based on clinical criteria and pedigree. The older cousin underwent a total optical correction and a right unilateral cochlear implantation followed by speech therapy with a satisfactory result after a follow-up of two years. Unfortunately, the little cousin died following a head trauma.

Conclusions

Tietz syndrome is a rare autosomal dominant genetic disorder, characterized by generalized albinism with bilateral profound hearing loss. It results from a nontruncating mutation in the basic domain of in the MITF gene. Its management must include, in addition to hearing and ophthalmic rehabilitation, the research and treatment of cardiac malformations which may be life-threatening.

Piebaldism: A brief report and review of the literature

Piebaldism is a rare autosomal dominant disorder of melanocyte development characterized by a congenital white forelock and multiple symmetrical stable hypopigmented or depigmented macules. We report a family with piebaldism affecting three successive generations and also review the literature.

Infancy- and childhood-onset dyschromatoses

The dyschromatoses are a group of pigmentary disorders characterized clinically by mixed and often guttate hypopigmented and hyperpigmented lesions. There are many conditions that present with dyschromatosis, including genodermatoses, inflammatory skin diseases, infections, drug and chemical use, and nutritional disorders. Some conditions have extracutaneous features. Poikiloderma (a combination of hypo- and hyperpigmentation with telangiectasia and atrophy) must be excluded. In this article, we describe the dyschromatoses typically presenting in infancy and childhood, most of which are genodermatoses. The approach we have taken in classifying them is based on organ involvement. We hope this article will serve as a guide for dermatologists to the recognition of these uncommon conditions.

Pigmentary disorders in the Mediterranean area

The Mediterranean area represents the area of land that borders the Mediterranean basin. It is composed of several countries that share many geographic and racial characteristics. Although Mediterraneans seem to share common skin type and are subjected to similar enviromental factors, they still represent a genetic and socioeconomic diversity. True prevalence of pigmentary disorders in this area depends on large epidemiologic studies, including countries that are not available. This article, however, highlights and classifies the most important developmental (heritable-genetic) and acquired pigmentary disorders seen and reported in this important area of the world.

Hypomelanotic Conditions of the Newborn and Infant

Depigmented nevi, pityriasis alba, and postinflammatory hypopigmentation are the most frequent hypomelanotic conditions in newborns and infants. These, and examples of less frequent hypopigmentations are briefly discussed in this article. A new classification for depigmented nevi is also proposed.

Sensorineural hearing loss, early greying, and essential tremor: a new hereditary syndrome?

OBJECTIVE

To present a syndrome composed of sensorineural hearing loss, early greying of scalp hair, and adult-onset essential tremor.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary care academic hospital.

RESULTS

Three individuals were seen with this triad, each with family members with similar features. Our patients are a 65-year-old man and two women in their 40s. Two noted hearing loss in adulthood, one as a child. All had complete greying in their 20s. The women developed essential tremor in their 20s, and the man in his 50s. All individuals have blue eyes without heterochromia. Additional evaluation failed to further categorize these patients. Each has two or more immediate family members with a combination of these findings. Molecular genetic testing suggests this is not a variant of Waardenburg syndrome.

CONCLUSION

We believe this represents a previously unreported hereditary syndrome.

SIGNIFICANCE

This new syndrome should be considered in the context of other syndromes involving audition, pigmentation, and movement.

Incontinentia pigmenti achromians (Ito)

A patient with incontinentia pigmenti achromians was reported. She displayed other abnormalities such as a saddle nose, malformed auricles, growth retardation, convulsions and abnormal EEG. Histopathologically, a partial decrease in melanin granules in the basal layer and the presence of melanocytes which showed a weak dopa reaction were the main findings. The hypofunction of melanin production was detected by electron microscopy.

Evaluation of vestibular function in young children

Together, these tests provide a full evaluation of vestibular function in infants and small children. If attention is paid to creating the appropriate testing environment, and interpretation of the tests takes into account the unique properties of the responses of infants and young children, this testing can provide a useful adjunct to audiometric evaluation in young children.

Piebaldism, Waardenburg syndrome, and related disorders of melanocyte development

Recent years have seen the identification of a complex network of interacting genes that regulates embryonic development of melanocytes, and many different genetic disorders of melanocyte development of both humans and the laboratory mouse have now been associated with abnormalities of these regulatory genes. Disorders of melanocyte development are characterized by heterogeneous distribution of pigmentation, so-called 'white spotting,' typified by piebaldism and Waardenburg syndrome. It is now clear that these disorders of pigment cell development represent a subgroup of the neurocristopathies, involving defects of various neural crest cell lineages that include melanocytes, but also involving many other tissues derived from the neural crest.

Confirmation of the Yemenite (Warburg) deaf-blind hypopigmentation syndrome

The Yemenite deaf-blind hypopigmentation syndrome is a rare disorder characterized by severe early hearing loss, microcornea and colobomata, and cutaneous pigmentation abnormalities. A girl with similar skin symptoms and hearing loss, but no microcornea or colobomata is described and compared to other reported patients.

Abnormalities of the auditory brainstem response in vitiligo

Accumulating evidence suggests that vitiligo is a systemic disease affecting the entire pigmentary system and possibly the melanin-containing cellular elements of the nervous system. In the present paper we comparatively study the auditory brainstem response (ABR) of 30 patients with active vitiligo and 50 healthy human subjects in order to detect possible subclinical abnormalities of the auditory system in this disorder. Our findings reveal a statistically significant (p < 0.01) decrease of the I peak latency and a statistically significant (p < 0.01) increase of the I-III interpeak latency in the patients as compared to the controls. The decrease of the first peak latency may be due to a numerical decrease of active melanocytes in the inner ear which results in an impairment of the ion exchange between the endolymph and perilymph. The increase of the I-III interpeak latency may be explained in terms of an abnormal synaptic activity and transmission of the action potential from the auditory nerve to the superior olive.

Clinical response of alopecia, trichorrhexis nodosa, and dry, scaly skin to zinc supplementation

Two unrelated patients had dry brittle hair, alopecia, trichorrhexis nodosa, dry scaly skin, pigment dyschromia, short stature, and neurosecretory growth hormone deficiency. By means of the zinc tolerance test, patient 1 was shown to have zinc deficiency, whereas no clear zinc deficiency could be demonstrated in patient 2. In both patients, hair and the skin abnormalities responded to oral zinc therapy.

Hearing impairment and pigmentary disturbance

Hearing impairment is a variable manifestation of several heritable conditions in which pigmentation of the skin or eyes is abnormal. Some of these disorders are well recognized although uncommon, while others are virtually private syndromes. Practical issues concerning the major conditions of this type are reviewed in this article on a basis of a survey of 4452 profoundly deaf children attending special schools in Southern Africa, together with investigations in affected families. The Waardenburg syndrome (WS), which is the most common deafness-depigmentation disorder, was present in 121 (2.7%) of the 4452 deaf scholars. Further studies in 7 multigeneration affected families confirmed phenotypic variability and indicated a need for internationally agreed diagnostic criteria. In 4 Cape Town families of mixed ancestry the WS-I gene was linked to the 2q37 locus, but in another large kindred no linkage could be demonstrated. Nonallelic heterogeneity is possible. There is uncertainty concerning possible interrelationship between WS and piebaldism. The phenotypic consistency of a South African family in which 7 persons in 3 generations had gross piebaldism in the absence of disturbance of hearing or involvement of the eyes and periorbital structures is suggestive that this disorder and WS are separate entities. Molecular investigations indicate that the gene for piebaldism in this kindred is not situated at the WS-I locus 2q37. Deafness and hyperpigmentation are present in neurofibromatosis type II (acoustic neuromata) and the multiple lentigines syndrome, while retinal pigmentation is a feature of the Usher syndrome. This latter entity is apparently much less common in Southern Africa than in other parts of the world.

The Yemenite deaf-blind hypopigmentation syndrome. A new oculo-dermato-auditory syndrome

We have seen a Yemenite sister and brother with cutaneous hypomelanotic and pigmented spots and patches, microcornea, coloboma, severe hearing loss and normal karyotypes. Histopathological examinations of the skin showed absent melanocytes in the depigmented areas; in the normal and hyperpigmented skin there was abundant melanotic pigment. Similar patients have not been described previously, but there are corresponding mutations in mice and rats.

The ermine phenotype: pigmentary-hearing loss heterogeneity

The term ermine phenotype has been chosen to describe patients with white hair with black tufts. The patients also have sensorineural hearing loss. This rare phenotype may come about either by failure of migration of melanocytes or by an autoimmune mechanism. Examples of each are cited. The authors describe a possible third type. Comparison with other pigment loss-sensorineural hearing loss syndromes is made.

Biology of hypopigmentation

A review of the basics of pigment cell biology is followed by a discussion of the characteristics of several disorders of hypopigmentation. By determining such features as inheritance pattern, time of onset (congenital, childhood, adulthood), natural history (stable vs progressive), type of pigment loss (diffuse or circumscribed), distribution of lesions (generalized vs localized), degree of pigment loss (incomplete or complete), number of melanocytes, if any, in biopsy specimens of affected areas, type of melanocytic dysfunction, and associated inflammation or infection, one can classify the disorders of hypopigmentation. The proposed pathophysiology for each disorder of hypomelanosis is presented.

X-linked inheritance of ocular albinism with late-onset sensorineural deafness

We have investigated a large Afrikaner kindred in which seven males had ocular albinism and late-onset sensorineural deafness (OASD). The pattern of inheritance of OASD is X-linked recessive. To the best of our knowledge, this association has not previously been reported and in order to establish syndromic identity we describe and discuss the condition in this article.

Inappropriate use of albino animals as models in research

Sensory-neural, biochemical-metabolic, and physiological anomalies occur in albino mammals. There are ontogenic and biochemical parallels between the senses, peripheral nervous system, endocrine glands, metabolism, and melanin pigmentation. All albino mammals examined have abnormal optic systems. Many drugs cannot be adequately evaluated in an albino model because of melanin's ability to bind and interact with some chemicals. There is evidence that a general reduction in melanin pigment is correlated with a paucity of amino acids necessary for normal chemical function of the brain. There is a high probability that enzyme levels indicative of metabolic performance are deficient in the liver and kidneys oif albinos. Congenital defects are associated with hypopigmentation in animal models and human syndromes. Melanin is found in abundance in the eye, inner ear, and midbrain where neural impulses are initiated indicating a possible role as an electrophysiologic mechanism. Microwave irradiation differentially affects albino and pigmented animals. Implications of these observations and other reports of anomalies associated with hypopigmentation suggest caution in the use of albino and other hypomelanotic animals as normal models in biological research.

Mutations affecting pigmentation in man: I. Neuroectodermal melanolysosomal disease

We describe a syndrome identified in three consanguineous families who had two and probably four common ancestors five generations ago. The syndrome is characterized by profound dysfunction of the central nervous system, silver-leaden colored hair, abnormal melanosomes and melanocytes, and abnormal inclusion bodies in fibroblasts, bone marrow histiocytes and lymphocytes which appear to represent abnormal lysosomal bodies. Because of the biochemical relationships between melanin-melanosomes and neuromelanin, we think that all the manifestations of the condition are related to and represent pleiotropic effects of a newly identified gene in man in its homozygous state. Biochemical reactions of the cells of these patients indicate presence of tyrosinase in the melanosomes.and show that the substance accumulated in cultured fibroblasts and in the bone marrow histiocytes is a PAS and Oil-red-O positive material but is Oil-red-O negative after extraction; it has the typical reactions of melanin withe the Masson and Fontana stain, but cannot be considered typical melanin, since without stain it is colorless. The ultrastructural studies showed round granules with variable matrix, similar in fibroblast and bone marrow, and with variable intensity of reaction to osmium. This mutation principally affects the neuroectoderm, but also the mesoderm.

Diseases of Jews

The relative social and genetic isolation of Jews from other communities, which was much more marked in the past than now, has led to the belief that they are unusually prone to a variety of illnesses. Until the last few decades assessments of the incidence of various diseases among them were usually based on impressions rather than planned surveys or careful analyses, and many misconceptions still persist. It is proposed to consider the present state of knowledge as well as to indicate the historical and social basis for any tendencies for Jews to suffer from, or perhaps to resist, some diseases. No attempt has been made to analyse every single report in which Jewish pre-disposition to various diseases is mentioned; attention will be focused on those conditions that have received greater attention or from which it is possible to draw meaningful conclusions.

Hearing impairment in female carriers of the sex-linked syndrome of deafness with albinism

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Inherited diseases of the inner ear in man in the light of studies on the mouse

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