Hereditary koilonychiaL60.83

The hereditary (autosomal dominant) form of koilonychia is a rare ectodermal malformation. It is characterized by a deformity of the nails with a cup-like hollowing of the nail plate, which is detached at the edge. Through this a spoon-like form is formed, which was the cause of its name. The number of affected nails can vary.

Klin: Hellier (1950) reported about a family in which 14 persons had a koilonychia over 4 generations. In some members of the family all nails on hands and feet were affected (20-nail-dystrophy). In others only the big toenails were changed, others showed a different pattern of infection of the finger and/or toe nails

Schleutermann et al (1970) reported 5 generations of a family. In 8 persons different degrees of koilonychia were detectable. The inheritance pattern was consistent with an autosomal dominant inheritance.

Hereditary koilonychia are found coincidentally in the following syndromes:

• Keratosis palmoplantaris transgrediens
• melanosis diffusa congenita
• Monilethrix Syndrome
• Trichomegaly Syndrome
• Trichothiodystrophy
• Witkop syndrome (tooth and nail syndrome)

1. Hellier FF (1950) Hereditary koilonychia. Brit J Derm 62: 213-214.
2. Mutoh M et al (2015) A syndrome of leukonychia, koilonychia and multiple pilar cysts. Acta Derm Venereol 95:249-250
3. Pancar GS et al (2013) Irritant nail dermatitis of chemical depilatory product presenting with koilonychia. Cutan Ocul Toxicol 33:87-89
4. Prathap Pet al. (2010) Familial koilonychia. Indian J Dermatol 55:406-407
5. Schleutermann DA et al (1970) A kindred of koilonychia: linkage data. On J Hum Genet 22: 390-395
6. Taguchi Y et al (2013) Koilonychia in a patient with subacute iron-deficiency anemia. Internal Med 52: 2379