Nailing the Diagnosis: Koilonychia

Vivek Kumar, MD; Sourabh Aggarwal, MD; Alka Sharma, MD; Vishal Sharma, MD

Summer 2012 - Volume 16 Number 3

A 22-year-old man presented with complaints of chronic diarrhea, general weakness, and easy fatigue. He had been progressively symptomatic for 6 months. On examination, he had pallor and spoon-shaped nails (Figure 1). The rest of the examination findings were normal. Laboratory studies revealed anemia (hemoglobin, 8 g/dL; total leukocyte count, 5400/mm3; platelet count, 432,000/mm3; and peripheral blood smear suggestive of microcytic and hypochromic pattern). The iron profile was suggestive of iron-deficiency anemia. Stool was normal. Immunoglobulin A antitissue transglutaminase was elevated, at 43 U/mL (normal, <8 U/mL). Gastroduodenoscopy was suggestive of grooving in the second part of the duodenum. Duodenal biopsy revealed increased intraepithelial lymphocytes and crypt hyperplasia. The patient was started on a gluten-free diet and iron supplementation. At a 6-month follow-up, the anemia had resolved, and antitissue transglutaminase antibody levels had normalized.

Koilonychia is an abnormality of the nails that is also called spoon-shaped (concave) nails.1 It is primarily recognized as a manifestation of chronic iron deficiency, which may result from a variety of causes, such as malnutrition; gastrointestinal blood loss; worms; gastrointestinal malignancy; and celiac disease, as in the present case.2 Other causes of koilonychia are high altitude, trauma, and exposure to petroleum products, and it can even be hereditary.1,3,4 Therefore, spoon-shaped nails should prompt an evaluation for possible iron deficiency and the underlying cause.



Leslie Parker, ELS, provided editorial assistance.

    1.    Fawcett RS, Linford S, Stulberg DL. Nail abnormalities: clues to systemic disease. Am Fam Physician 2004 Mar 15;69(6):1417-24.
    2.    Kumar G, Vaidyanathan L, Stead LG. Images in emergency medicine. Koilonychia, or spoon-shaped nails, is generally associated with iron-deficiency anemia. Ann Emerg Med 2007 Feb;49(2):243, 250.
    3.    Prathap P, Asokan N. Familial koilonychia. Indian J Dermatol 2010 Oct;55(4):406-7.
    4.    Sawhney MP. Ladakhi koilonychia. Indian J Dermatol Venereol Leprol 2003 Mar-Apr;69(2):79-80.


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