Treatment of fungal toenails can be a tricky process, whether you use oral drugs, topical lacquers or a combination of both. In an earlier blog I discussed a chemical nail avulsion using urea as a means of treating onychomycosis in the toenails. Often you hear the phrase “the only treatment worth doing is to perform a total nail avulsion (TNA) and be rid of it”. But is there any truth behind this? Is a TNA really an effective treatment for fungal infected nails?
Looking through the literature there are a small number of cases published (1-3) but no real research . Only one study (1) has taken a more comparative approach with a formalised study. In this paper they looked at the effectiveness of nail avulsion (without phenolisation) with subsequent application of a topical azole antifungal cream. In this study, 40 patients with confirmed onychomycosis received a total nail avulsion (no phenol) with one of two topical creams (oxiconazole or ketoconazole). Within each group, half were instructed to use the cream post-operatively under occlusion and half not, until the new nail had completely regrown. The results were interesting as only 27 out of the original 40 patients completed the study! Of these the cure rates were disappointing, with only 15 out of 27 patients (56%) reaching a mycological cure. The data showed there was a slightly better outcome if the topical azole applied after avulsion was under occlusion, but this did not reach statistical significance.
Digging deeper, it also showed that those who had a mycological cure were patients with distal and lateral nail disease (DLSO) – effectively mild to moderate nail bed disease. No patient enrolled in the study with a totally dystrophic nail (TDO onychomycosis) reached a mycological cure suggesting that this type of nail dystrophy is particularly tricky to treat. Logically though, if you are applying a cream, the exposed nail bed should be easy to treat but with TDO there will be infection in the matrix – a place where the cream may not actually reach as well under the eponychial fold.
There are limitations to mention here. As I always say, unless the skin is treated as well, rapid relapse or re-infection is a real possibility and in this study it does not seem to take any preventative measures to counter this risk. In addition, this study suffered the effects that we so often see in clinical practice – poor patient compliance. Owing to the prolonged need for the patient to apply the cream daily to the area (often for months), it is quite likely many patients dropped out – possibly as they felt the nail avulsion alone should have been sufficient to resolve the condition or just through perceived lack of progress over the months.
Consequently, the bottom line is that as it stands we need further research, particularly for totally dystrophic nails which seem hard to cure even after a total avulsion.
References
1. Baran R, Hay RJ. Partial surgical avulsion of the nail in onychomycosis. Clin Exp Dermatol. 1985;10(5):413-8.
2. Hettinger D, Valinsky M. Treatment of onychomycosis with nail avulsion and topical ketoconazole. J Am Podiatr Med Assoc. 1991;81(1):28-32.
3. Lai WY, Tang WY, Loo SK, Chan Y. Clinical characteristics and treatment outcomes of patients undergoing nail avulsion surgery for dystrophic nails. Hong Kong medical journal = Xianggang yi xue za zhi. 2011;17(2):127-31.
4. Grover C, Bansal S, Nanda S, Reddy BSN, Kumar V. Combination of surgical avulsion and topical therapy for single nail onychomycosis: a randomized controlled trial. Br J Dermatol. 2007;157(2):364-8.