Differential Diagnosis for Yellowing Nails and Falling Off
Single Most Likely Diagnosis
- Onychomycosis: This is a fungal infection of the nails, which is the most common cause of yellowing and brittle nails that may fall off. It's justified due to its high prevalence and the typical presentation of nail discoloration and brittleness.
Other Likely Diagnoses
- Psoriasis: Nail psoriasis can cause yellowing, pitting, and separation of the nail from the nail bed, potentially leading to the nail falling off. This diagnosis is considered due to the common involvement of nails in psoriatic patients.
- Eczema/Dermatitis: Certain types of eczema, especially those involving the hands, can lead to nail changes including yellowing and brittleness. The justification comes from the potential for skin conditions to affect nail health.
- Trauma: Repeated or severe trauma to the nails can cause them to become discolored and potentially fall off. This is a common and plausible explanation for the symptoms.
Do Not Miss Diagnoses
- Thyroid Disorders: Both hypothyroidism and hyperthyroidism can cause changes in the nails, including brittleness and separation. Missing a thyroid disorder could have significant health implications, making it a "do not miss" diagnosis.
- Cancer: Certain types of cancer, such as squamous cell carcinoma of the nail bed, can present with nail changes. Although rare, the potential severity of cancer makes it crucial not to overlook.
- Systemic Lupus Erythematosus (SLE): SLE can cause a variety of nail changes, including brittleness and discoloration. Given the serious nature of SLE, it's essential to consider it in the differential diagnosis.
Rare Diagnoses
- Yellow Nail Syndrome: A rare condition characterized by yellowing of the nails, lymphedema, and respiratory issues. It's considered rare but should be kept in mind for patients with the characteristic triad of symptoms.
- Nail-Patella Syndrome: A genetic disorder that affects the development of nails and kneecaps, among other features. It's rare and typically identified by a combination of nail abnormalities and other systemic features.
- Darier's Disease: A rare genetic disorder that affects the skin and sometimes the nails, causing abnormalities. The nail involvement can include red and white lines, V-shaped nicks at the distal end, and subungual hyperkeratosis, which might lead to nail loss.