From the Guidelines
Thickened toenails are primarily caused by fungal infections, which account for about 50% of all cases, as well as other factors such as aging, repetitive trauma, and certain medical conditions like psoriasis and peripheral vascular disease. The causes of thickness in toenails can be multifaceted, involving various factors that contribute to the condition. Fungal infections, particularly those caused by dermatophytes, are a leading cause of onychomycosis, a condition characterized by thickening, discoloration, and brittleness of the nails 1.
Key Factors Contributing to Toenail Thickening
- Fungal infections: These are the most common cause, with dermatophytes being the primary pathogens involved 1.
- Aging: As people age, their nails naturally thicken due to decreased circulation and slower nail growth.
- Repetitive trauma: Activities like running or wearing ill-fitting shoes can cause the nail to thicken as a protective response.
- Medical conditions: Psoriasis, peripheral vascular disease, and other conditions can lead to nail thickening due to their effects on skin cell turnover, blood flow, and overall health.
Importance of Accurate Diagnosis
Accurate diagnosis is crucial for effective treatment. Conditions like Candida nail infection, which accounts for 5-10% of all onychomycosis cases, can mimic dermatophyte infections but require different treatment approaches 1. Non-infectious conditions such as chronic trauma, psoriasis, and lichen planus can also cause nail changes that resemble onychomycosis, highlighting the need for thorough examination and mycological confirmation before initiating treatment 1.
Treatment Approaches
Treatment depends on the underlying cause of the thickening. For fungal infections, antifungal medications such as oral terbinafine or topical ciclopirox are effective, while proper foot hygiene, comfortable shoes, and regular nail trimming can help prevent trauma-related thickening 1. In cases of treatment failure or relapse, considering alternative drugs or nail removal followed by antifungal therapy may be necessary 1.
Given the complexity and potential for underlying health conditions, if you notice persistent nail thickening, it is essential to consult a healthcare provider for a proper diagnosis and treatment plan. This approach ensures that the treatment addresses the root cause of the condition, whether it be a fungal infection, a medical condition, or another factor, thereby improving outcomes in terms of morbidity, mortality, and quality of life.
From the Research
Causes of Thickness in Toenails
- Onychomycosis, a fungal infection of the nail, is a common cause of thickening of the toenails 2, 3, 4, 5, 6
- Diabetes is a risk factor for onychomycosis, and patients with diabetes are more likely to experience thickening of the toenails due to this infection 2, 3, 5
- Other factors that may contribute to thickening of the toenails include:
- Vascular insufficiency
- Impaired wound healing
- Compromised immunologic status
- Peripheral neuropathy
- Retinopathy
- Obesity 5
- Nondermatophyte fungi can also cause onychomycosis and thickening of the toenails, and may be more difficult to treat than dermatophyte infections 3
- The use of certain medications, such as immunosuppressive therapy, may also increase the risk of onychomycosis and thickening of the toenails 3