Keys To Managing Severe Onychomycosis
How Effective Is Surgical Avulsion?
In severe cases of onychomycosis in which there is a history of significant recurrent pain or bacterial infection, one can attempt temporary surgical removal of the entire nail plate. A complete medical history and review of systems with ankle brachial indices can be useful to document healing capacity. Total nail plate avulsion typically heals within a few weeks. One would prescribe topical antifungals throughout the nail plate regeneration phase of treatment.
Depending on the duration and severity of onychomycosis, deviation or scarring of the nail matrix may have taken place, permanently altering the nail plate alignment and nail matrix orientation. This leaves the new nail plate to regrow in a still thickened form that is dystrophic and non-adherent to the nail bed. There is also a risk with surgical avulsion of permanent nail plate loss. Patients should be aware of this potential complication.
In some cases of severe, chronic onychomycosis combined with onychogryphosis, one may consider permanent nail removal. The bulk of the problem is typically reduced but often residual nail matrix produces partial nail plate or spicule that can be annoying to the patient who expects a normal nail bed.
Grover and colleagues in 2007 reported on surgical avulsion of single, moderate to severe onychomycosis followed by twice daily topical ketoconazole (Nizoral, Janssen Pharmaceuticals) or oxiconazole cream (Oxistat, PharmaDerm) in 40 patients.31 One-third of the patients dropped out of the study. Of the remainder, 43 percent were cured. None of the severe cases were cured. They concluded that surgical avulsion followed by topical antifungal therapy could not be generally recommended treatment.
What About Urea Avulsion?
Pandhi and Verma recently detailed a topical technique for nail removal utilizing 40% urea. South and Farber first described this technique in 1980, and Averill and Scher subsequently modified it in 1986.32-34
Urea ointment paste is formulated to include 40% urea, 5% white beeswax or paraffin, 20% anhydrous lanolin and 35% white petrolatum.32 One can use a 1/8-inch felt oval aperture pad to build a wall around the entire nail plate. This creates a shallow well that one packs with the urea paste and secures with occlusive tape. Patients keep the dressing dry and in one week, simple debridement can remove the nail plate.32
Can Laser Therapy Have An Impact?
In the past, ablative lasers like the carbon dioxide laser have permanently removed severely mycotic nail roots.35 Recently, Landsman and Robbins have been able to demonstrate the effectiveness of a dual band non-ablative laser therapy in mild, moderate and severe onychomycosis.36 At nine months, about one-third of their treated population achieved both negative cultures and negative microscopy, qualifying as “mycological cures.”
The FDA has approved non-ablative lasers for temporary clearing of mild to moderate onychomycosis.37 These lasers do not destroy mammalian tissue. They selectively deactivate fungus, bacteria plasma and mitochondria by endogenously generating radical oxygen species, causing photoinactivation and photodamage.38
Preliminary 1064 nm laser study data on several patients from the Cleveland Foot and Ankle Clinic with moderate to severe infections have shown improved proximal clear zones and reduced Onychomycosis Severity Indices by 22 percent.39 Quality of life scores have improved 20 percent. Non-ablative lasers seem to hold promise as adjunctive cosmetic clearing approaches but do not appear to be magic wands to cure onychomycosis.40,41