BADS

At a glance

BADS is an acronym that stands for Black locks with Albinism and Deafness Syndrome. Features in newborns with BADS include white hair, eyebrows, and eyelashes (ermine-like camouflage), some black locks, and depigmented skin with some brown spots. Other features include nystagmus, photophobia, retinal depigmentation, and deafness. Mild mental retardation is possible.

Synonym

Ermine Phenotype Syndrome (Pigmentary Disorder with Hearing Loss). (Some experts consider BADS and ermine phenotype different entities, but this is unclear due to the small number of cases.)

History

In 1979, Witkop described the association of albinism with black locks and congenital hearing loss.

Incidence

Fewer than 10 cases have been reported.

Genetic inheritance

Autosomal recessive.

Pathophysiology

Ultrastructural analysis of the skin and melanocytes in one patient showed normal numbers and migration pattern of melanocytes, but it pointed to morphologically abnormal melanosomes, suggesting that the anomaly could be due to a defect in the melanin synthesis within the melanosomes. In other cases, the melanocytes from hair and skin were absent except from pigmented areas, which was considered to be an indication for failed melanocyte migration.

Diagnosis

Based on the characteristic clinical features, which include white hair, eyebrows, and eyelashes with scattered black tufts (black locks), reminiscent of the winter color change of the ermine (Mustela erminea; stoat or short-tailed weasel) fur from brown-black to white, which affects the entire body, except for the distal half or third of the tail that remains brown-black.

Clinical aspects

Pigmentation of skin and hair may be normal at birth, but then affected patients start to develop patchy depigmentation with persistence of normally or hyperpigmented areas in the first year of life. The initially normal pigmented hair becomes progressively replaced by white hair with black patches. The phenotype of this disorder seems fairly broad, and these changes may be accompanied by global developmental delay, microcephaly, hypotonia, profound sensorineural hearing loss, and growth retardation Some cases seem to have normal retinal pigmentation, while others have a total absence of fundal pigment with nystagmus, photophobia, and markedly reduced visual acuity. MRI scanning of the brain (available in one patient) revealed delayed myelination of the corpus callosum, decreased central white matter, and numerous small calcifications within the periventricular white matter, which over time progressed to extensive calcifications of the gray-white matter junction throughout the brain. Muscle biopsy in that same patient showed variable myofiber atrophy and hypertrophy with probable fiber-size disproportion and neuropathic-type grouping, which was interpreted as a chronic lower motor unit disorder. Muscle ultrastructure on electron microscopy was normal. Early recognition of hearing loss and protection from ultraviolet sunlight (skin and eyes) are ...