This is not always an accurate way of diagnosing a fungal nail infection, but where there has been another skin infection such as athletes foot in the region of the nail problem, this is by far the most likely cause.
The most common way of identifying a fungal nail infection is by collection of debris and maybe even a portion of the nail and sending this away for analysis. This is known as a mycology sample. This sample is then analysed and examined microscopically to establish what the causative organism is. This may involve the need to grow the fungus on a petri dish, so diagnosis can take some time. Although the diagnosis of a fungal nail infection is often clear based on clinical findings there is reason to confirm the diagnosis using culture and microscopic methods before the commencement of a prolonged treatment.
The obtaining of a technically successful specimen is sometimes difficult and wrong diagnoses are relatively common, so it is often the case that fungal nail infection is diagnosed through appearance and the exclusion of other potential reasons for the nail damage. Several other conditions can affect the nail giving a similar appearance such as psoriasis, which can lead to crumbling and destruction of the nails. As psoriasis is a genetic condition, ruling out a family history of psoriasis means that a diagnosis of fungal nail infection is a lot more likely. It is also important to rule out recent damage which may have occurred to the nail. This may be caused by the nail striking and object or rubbing against a shoe when walking or running.
Treatment is challenging
A fungal nail infection does not get better without treatment and it is estimated that only about 50% of treated fungal infections of toenails are cured completely even after the most potent oral treatment with antifungals. Fungal infections of the fingernails, however, are almost always cured. The length of treatment varies from a few weeks up to two years, depending on the severity of the infection when first treated. The best response is obtained if the treatment is begun immediately after the infection is noticed and diagnosed. The renewal of the nail of the big toe may take up to two years in the aged patient. The length of treatment does not, however, correlate directly with the speed of nail growth. It is essential to achieve a sufficient concentration of medicine into the nail plate and below it when the antifungal effect lasts for months. The final result of treatment is seen only after months of cessation of treatment. Urea solution treatment of thickened and dystrophic nails may help to improve the treatment result.
The alternative treatments of fungal nail infections are local treatment (such as Abicin) or an antifungal medicine by mouth or both treatments together. Local treatment is most effective for fungal infections of the nail tip when little time has passed since the onset of infection. For the treatment of fully dystrophic fungal nail infections local treatment alone is not appropriate. The most effective treatment of a fungal nail infection in this state would be antifungal tablets taken by mouth. These are not suitable for everyone though, so you should consult your physician to ensure that they are the right treatment for you.