Differential Diagnosis for Nail Fungus
If an image is loaded to diagnose nail fungus, the following differential diagnoses should be considered:
- Single most likely diagnosis
- Onychomycosis: This is the most common cause of nail fungus, accounting for approximately 50% of all nail infections. It is caused by fungal organisms such as dermatophytes, yeast, or molds, and can be identified by characteristic changes in the nail, including thickening, discoloration, and brittleness.
- Other Likely diagnoses
- Psoriasis: Nail psoriasis can cause changes in the nail that resemble fungus, including thickening, pitting, and discoloration. However, psoriasis often has other characteristic skin lesions.
- Eczema (Dyshidrotic eczema): This condition can cause nail changes, including thickening and brittleness, and may be accompanied by skin lesions on the hands or feet.
- Lichen planus: This is an inflammatory condition that can affect the skin and nails, causing changes such as thinning, ridging, or brittleness.
- Do Not Miss diagnoses
- Squamous cell carcinoma: Although rare, this type of skin cancer can present as a nail lesion, and if missed, can have serious consequences.
- Melanoma: A type of skin cancer that can occur under the nail, melanoma is rare but potentially deadly if not diagnosed early.
- Paronychia: This is an infection of the skin around the nail, which can be caused by bacteria or fungi, and if left untreated, can lead to serious complications.
- Rare diagnoses
- Nail trauma: Trauma to the nail can cause changes that resemble fungus, including thickening or discoloration.
- Nutritional deficiencies: Deficiencies in vitamins or minerals, such as vitamin B7 (biotin) or iron, can cause nail changes, including thinning or brittleness.
- Systemic diseases: Certain systemic diseases, such as thyroid disease or diabetes, can cause nail changes, including thickening or discoloration.