From the Guidelines
Nail spooning, or koilonychia, can occur despite normal ferritin levels, and its presence warrants further evaluation to rule out underlying systemic conditions. While iron deficiency anemia is a common cause of nail spooning, this condition can also result from other factors such as trauma to the nails, exposure to petroleum-based solvents, high-altitude living, Raynaud's disease, lupus, or certain genetic conditions 1. The European Consensus on the Diagnosis and Management of Iron Deficiency and Anaemia in Inflammatory Bowel Diseases highlights the importance of considering other variables, such as mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH), in the detection of iron deficiency, especially in the presence of inflammation 1.
Some key points to consider in the evaluation of nail spooning with normal ferritin levels include:
- The presence of inflammation, which can affect serum ferritin levels 1
- The possibility of other nutritional deficiencies, such as vitamin B12 or folate deficiency, which can cause macrocytosis 1
- The potential for underlying systemic conditions, such as thyroid disorders, hemochromatosis, or protein deficiencies, which can affect nail formation
- The importance of protecting the nails from trauma and harsh chemicals to support overall nail health
In terms of next steps, consulting with a dermatologist or primary care physician for proper evaluation is recommended, as they may perform additional tests to rule out other systemic conditions that can affect nail formation. Treatment will depend on the underlying cause, and maintaining good nutrition and hydration may also support overall nail health. The nail matrix (where nails form) is sensitive to many systemic and environmental factors, which explains why nail abnormalities can occur even when specific blood tests like ferritin appear normal 1.
From the Research
Significance of Koilonychia with Normal Ferritin Levels
- Koilonychia, also known as nail spooning, is a condition where the nails become thin and concave, often associated with iron deficiency 2.
- However, the presence of koilonychia with normal ferritin levels may indicate other underlying conditions, such as inflammatory or autoimmune disorders 3, 4.
- Ferritin levels can be influenced by various factors, including inflammation, infection, and autoimmune diseases, which can lead to elevated or decreased ferritin levels regardless of iron status 5, 3, 4.
- In some cases, genetic variants can affect ferritin production and function, leading to abnormal ferritin levels and related conditions, such as hypoferritinemia without anemia 6.
Diagnostic Considerations
- A thorough diagnostic workup is essential to determine the underlying cause of koilonychia with normal ferritin levels, including laboratory tests and medical history evaluation 2, 3, 4.
- Inflammatory and autoimmune disorders, such as adult-onset Still's disease and hemophagocytic lymphohistiocytosis, should be considered in the differential diagnosis of hyperferritinemia 5, 3.
- Genetic testing may be necessary to identify underlying genetic variants that affect ferritin production and function, such as the FTL variant described in 6.
Clinical Implications
- The presence of koilonychia with normal ferritin levels requires careful evaluation and management to determine the underlying cause and prevent potential complications 2, 3, 4.
- Treatment of underlying conditions, such as inflammatory or autoimmune disorders, may be necessary to manage symptoms and prevent disease progression 5, 3.
- Genetic counseling and testing may be recommended for individuals with a family history of ferritin-related disorders or abnormal ferritin levels 6.