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Notes: We report the first case of subungual perineurioma presenting as clubbing of one finger, an unusual clinical feature. Histological study showed a myxoid tumour but with, unexpectedly, a diffuse expression of CD34. Differential diagnoses between perineurioma and myxoid soft tissue tumours expressing CD34 are discussed.

Notes: We biopsied longitudinal erythronychia in 16 subjects, and found an onychopapilloma in 14 cases and Bowen’s disease in the remaining two. Shared clinical features in addition to erythronychia (or sometimes an interrupted line made up of splinter haemorrhages) were typically a longitudinal marked ridge of the nail bed expanded at the distal nail bed as subungual keratosis, and associated localized onycholysis. The presentation of Bowen’s disease in this pattern has not been previously reported. In all cases of onychopapilloma of the nail bed, acanthosis and papillomatosis were evident, and were associated with a keratogenous zone identical to the nail matrix. In addition, we found multinucleate giant cells in two onychopapillomas. We have therefore suggested that the term ‘localized, distal, subungual keratosis with multinucleate cells’ should be replaced by ‘onychopapilloma’ (nail-producing papilloma).

Notes: Fungal infections may be difficult to treat for several reasons. It is important to obtain the correct diagnosis, and select the appropriate antifungal agent and route. General considerations that may be associated with recurrent infections are, a genetic predisposition and suboptimal bioavailability of drug, resulting in insufficient concentration at the target site. The aetiologic organism, the severity of disease, other coexisting diseases, concomitant drug intake, and the presence of fungal infection at other sites are some factors that determine the choice of antifungal therapy and its route of administration, oral vs. topical lacquer. Local factors such as the thickness of the nail, presence of lateral onychomycosis, longitudinal spike, dermatophytoma and severe onycholysis are some factors that may determine the choice of secondary measures such as mechanical or topical treatment. Booster or supplemental therapy may be of benefit when the response to initial treatment is poorer than expected and unlikely to result in complete response. Steps should be taken to reduce the possibility of recurrence once cure has been achieved.

Notes: In view of recent advances in the development of antifungal agents, this study examined the possible synergy of two new antifungal agents, terbinafine and amorolfine. The study compared two different courses of terbinafine treatment combined with amorolfine 5% solution nail lacquer. Terbinafine was given orally for 6 (AT6 group) or 12 weeks (AT12 group) and amorolfine nail lacquer applied weekly for 15 months. A control group received terbinafine alone for 12 weeks. This was a randomized, prospective, open study of severe dermatophyte toenail onychomycosis with matrix region involvement. Nail samples were taken before the start of the study, at inclusion and at the visits at 6 weeks, 3, 9, 15 and 18 months. To assess the value of such combined therapy we chose an early parameter as the principal outcome variable, which was the result of mycological examination, including direct microscopy and culture, at 3 months (allowing a margin of 15 days). The secondary parameters of success were the mycological results at the later visits, clinical evaluation and a combined mycological–clinical response. Safety and tolerance were also assessed. Adverse events were recorded and liver function tests were performed monthly during the terbinafine treatment. Of the 147 patients included in the trial, 121 attended the 3-month visit, within a time limit of 15 days of 3 months after the beginning of treatment: 40 in the AT6 group, 40 in the AT12 group and 41 in the control group. In all, 32 of 121 patients (26·4%) had negative mycological results on direct microscopy and culture: 14 of 40 (35·0%) in the AT6 group, 11 of 40 (27·5%) in the AT12 group and seven of 41 (17·1%) in the control group. The cure rate for the global (mycological and clinical cure) response measured at 18 months in 145 patients was 44·0% (22 patients) in the AT6 group, 72·3% (34 patients) in the AT12 group and 37·5% (18 patients) in the terbinafine group. These results suggest that the combination of amorolfine and terbinafine may be of value in the treatment of severe onychomycosis. At the same time a pilot pharmacoeconomic analysis was performed demonstrating a better cost per cure ratio for the patients receiving combination treatment.

Notes: Combination therapy is one way of improving the cure rate of onychomycosis. The LION Study examined the efficacies of terbinafine and itraconazole. The Icelandic cohort of the study reported that after 5 years only 46% of the terbinafine-treated patients and 13% of the itraconazole-treated patients were still disease-free, suggesting that relapses and reinfections were common in the long term treatment of onychomycosis with monotherapy. Combination therapy is a well-established principle in mycology; the current strategy involves the combination of oral and topical antifungal treatments. A number of specific drug combinations have proved to be useful in the treatment of onychomycosis: tioconazole and griseofulvin, amorolfine and griseofulvin, amorolfine and terbinafine, and amorolfine and itraconazole. However, comparison of the combination trials can be difficult because of the short duration of some of the studies and variation in global cure rates. Although it is necessary to consider these factors it is clear that combination therapy offers advantages when compared with monotherapy. Combination therapy can be administered sequentially or in parallel. Parallel therapy is recommended for patients who are likely to fail therapy (e.g. patients with diabetes), whereas sequential therapy is recommended for patients who show a poor response to initial treatment.