Isolated congenital nail dysplasia
Synonyms
2
Overview
Isolated congenital nail dysplasia is an autosomal dominant disorder recently observed across five generations in a large family from southern Germany. Same condition was described in a Sicilian family by Pavone in 1982.
Isolated congenital nail dysplasia manifests from the first year of life. Affected family members showed no associated skin, hair or tooth alterations, as well as no malfunction of sweat glands or sensory organs.
Symptoms
The disorder is characterized by longitudinal streaks, thinning, and impaired formation of the nail plates leading to increased vulnerability of the free nail margins. Single nails may show longitudinal angular ridges that occasionally start at a conspicuous red prominence near the proximal nail fold, poorly developed lunulae, platonychia/koilonychias with the nail plate sometimes overgrowing the lateral nail fold.In most cases, all fingernails and toenails are similarly involved with some accentuation of the thumb and great toenails.
Histologic changes include hypergranulosis of the nail matrix and epithelial outgrowths from the nail bed. Patients do not show any alterations of hair growth and dentition, no malfunction of sweat glands and sensory organs, and no skeletal abnormalities.
Causes
The disease is inherited in autosomal dominant fashion with complete penetrance. The ICND gene is localized on chromosome 17p13.
Prevention
Not available. Genetic counselling may help in families where the disease occurred previously.
Diagnosis
Clinical picture and presence of the condition in several members of one family. Genetic testing.
Prognosis
The ICND is a lifelong condition. Patient documented by Pavone (1982) lost his nails almost completely in his twenties and did not regain them before he died at 77. Also his son showed severe nail alterations about 25 years ago and since then the anomaly has been slowly worsening. This suggests that ICND is a slow and inevitably progressive disease, even if the only discomfort it causes is the cosmetic aspect.
Treatment
There is no known treatment for ICND. Symptomatic treatment helps alleviate the disease burden.
Resources
[1] Krebsová A et al – Assignment of the gene for a new hereditary nail disorder, isolated congenital nail dypslasia, to chromosome 17p13. J Invest Dermatol. 2000 Oct;115(4):664-7.
[2] Hamm H – Isolated congenital nail dysplasia: a new autosomal dominant condition. Arch Dermatol. 2000 Oct;136(10):1239-43.
[3] Arias, A. M., Yung, C. W., Rendler, S., Soltani, K., Lorincz, A. L. Familial severe twenty-nail dystrophy. J. Am. Acad. Derm. 7: 349-352, 1982.
[4] Pavone, L., Li Volti, S., Guarneri, B., La Rosa, M., Sorge, G., Incorpora, G., Mollica, F. Hereditary twenty-nail dystrophy in a Sicilian family. J. Med. Genet. 19: 337-340, 1982.