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Koilonychia: Causes and Treatment

  • The term "koilonychia" is derived from the Greek words "koilos" (hollow) and "onikh" (nail). 
  • This nail abnormality is also known as spoon-shaped nails. 
  • The nail abnormality is distinguished by a thin and concave nail that can occur horizontally and vertically.
spoon shaped nails
  • The nail seems to be centrally depressed and everted laterally. 
  • It is found in infants, children, and adults
  • When a patient exhibits this symptom, it is critical to investigate further to determine whether there are any more serious health concerns present.

Causes Of Koilonychia

  • Causes of koilonychia are multiple, they can be classed as hereditary or congenital, acquired, or idiopathic. 


1. In Adults

  • It is assumed to be a symptom of chronic iron deficiency and anemia.
  • Koilonychia can be a symptom of inflammatory skin diseases like lichen planus or psoriasis, or it can be the result of systemic changes like endocrine disorders (hypo or hyperthyroidism and diabetes mellitus), Plummer-Vinson syndrome, alopecia areata, onychomycosis, vascular disorders, musculoskeletal disorders, trauma, high altitude, genetic, occupational exposure to petroleum products

2. In Children

  • Kids with other systemic disorders are more likely to develop acquired nail disorders.
  • Koilonychia is frequently found to be idiopathic in newborns and presents as a normal variant in 33% of cases, especially affecting the big toe, which regresses spontaneously after the age of 9 years once the nail plate thickens and hardens.


Treatment of Koilonychia

  • The management of koilonychia usually requires treating the underlying illness. Although there are several causes of koilonychia, the underlying cause can be selected based on age, personal, family, and occupational history, system review, and a detailed physical examination. Koilonychia can be a sign of either a dermatologic or a systemic disorder.
  • Most cases with acquired koilonychia are reversible.
  • Nails in infants are often thin and soft, with frequent physiological koilonychia that is best left untreated and necessitate a wait-and-see approach.


1. Iron Deficiency Anemia

  • Meat and animal products are the finest sources of dietary iron for non-vegetarians, whereas beans, leafy greens, and fortified grain products are good sources of iron for vegetarians. 
  • Combining these iron sources with citrus fruits and vitamin C-rich iron dietary sources aids in iron absorption. After iron replacement, the nail irregularity normally returns to normal within 4-6 months.


2. Idiopathic Koilonychia

  • There is no effective treatment available if the etiology of the koilonychia is idiopathic or inherited.



  • Sobolewski S, Lawrence AC, Bagshaw P. Human nails and body iron. J Clin Pathol. 1978 Nov;31(11):1068-72.
  • Chelidze K, Lipner SR. The water-drop test for the diagnosis of koilonychia. J Am Acad Dermatol. 2017 Dec;77(6):e157-e158.
  • Wagner G, Rose C, Sachse MM. Clinical variants of lichen planus. J Dtsch Dermatol Ges. 2013 Apr;11(4):309-19.
  • Razmi TM, De D. Bead retention test in koilonychia. Indian J Dermatol Venereol Leprol. 2019 Mar-Apr;85(2):229-230.
  • Schons KR, Knob CF, Murussi N, Beber AA, Neumaier W, Monticielo OA. Nail psoriasis: a review of the literature. An Bras Dermatol. 2014 Mar-Apr;89(2):312-7.
  • Rathod DG, Sonthalia S. Spoon Nails. [Updated 2021 Dec 20]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK559311/




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