[Assessment of mycological and clinical factors on the course and results of treatment of mycotic infections in patients with recurrent onychomycosis]

Ann Acad Med Stetin. 2003:49:161-71.
[Article in Polish]

Abstract

In spite of excellent results of conservative treatment of onychomycosis, there is still a significant number of patients in whom the dermatophyte infection persists in deep layers of the nail plates. Intensive treatment must be undertaken in some of these patients, depending on their clinical state and extent of the persistent dermatophyte infection of the nails. The aim of this study was to determine fungal factors facilitating the persistence of dermatophytosis in nails and to evaluate clinical data of patients in whom conservative treatment was unsuccessful. The study also concentrated on the effectiveness of various kinds of onychomycosis therapy. A total of 704 patients with onychomycosis underwent therapy between 1995 and 2000. 155 patients were previously treated unsuccessfully with terbinafine or itraconazole. Apart from the method of therapy, the main factors influencing the results of therapy in 549 patients visiting the physician for the first time were: age and location and extent of dermatophyte infection. Observation of patients with recurrent mycosis revealed that repeated monotherapy with terbinafine or itraconazole is the least efficient regimen. Significantly better results were obtained with combined itraconazole and pentoxifylline or itraconazole and topical amorolphine. Undoubtedly, surgery is the most efficient method and almost always successful. Surgery remains burdensome and costly, necessitating not only removal of the nail, but also a monthly course of terbinafine and meticulous topical treatment until nail plate regrows. Analysis of factors being potentially capable of influencing the results of treatment revealed that enzymatic activity of dermatophyte is by far the most important one. When enzymatic activity of different dermatophyte species from patients with recurrent onychomycosis was compared with enzymatic activity of control species from patients who were never treated before, significant and characteristic statistical differences were noticed. Statistically significant differences between both groups were detected regarding activities of beta-glucosidase, lipase, arylamidase and N-acetyl-beta-glucosaminidase. Higher activities of these enzymes are characteristic for strains isolated from patients who have been unsuccessfully treated before. Undoubtedly, high enzymatic activity is an important factor favoring survival of dermatophytes in the nail. In conclusion, ineffective pharmacological treatment of fungal infection of nails may depend on both clinical features of the patient and the properties of infecting fungus, in particular on its enzymatic activity.

Publication types

  • Clinical Trial

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Drug Therapy, Combination
  • Epidermophyton / isolation & purification
  • Humans
  • Itraconazole / therapeutic use
  • Middle Aged
  • Morpholines / administration & dosage
  • Nails / surgery
  • Naphthalenes / therapeutic use
  • Onychomycosis / microbiology*
  • Onychomycosis / therapy*
  • Pentoxifylline / administration & dosage
  • Recurrence
  • Terbinafine
  • Treatment Outcome
  • Trichophyton / isolation & purification

Substances

  • Morpholines
  • Naphthalenes
  • Itraconazole
  • amorolfine
  • Terbinafine
  • Pentoxifylline