New criteria for the laboratory diagnosis of nondermatophyte moulds in onychomycosis

Abstract

We suggest that when NDM infection is found in the first culture, the patient should be re-examined in a subsequent visit in which three separate samples are taken from the affected nail. If NDM is confirmed in all three cultures, the diagnosis of NDM is established. Treatment should be recommended in patients who show positive results in all three cultures.

Non-dermatophyte moulds as skin and nail foot mycosis agents: Phoma herbarum, Chaetomium globosum and Microascus cinereus

“…Laboratory examination is very important to confirm the diagnosis of dermatomycoses and onychomycosis because the clinical appearance caused by one species of fungus is often indistinguishable from that caused by other fungi (Shemer et al 2009). In addition, the existence of environmental filamentous fungi that cause infections underlines the need to not disregard them as contaminants but to study these moulds as potential pathogens (Tullio et al 2008).…”

“…Subcultures were made on SAB agar and Oatmeal agar (Sigma) and incubated for at least 2 weeks at 25 C. Identification of moulds was based on macroscopic and microscopic characters of the colonies (performed with a 400Â optical microscope). The pathogenic significance of fungal agents was confirmed by repeating cultures to exclude cases of contamination: a total of three consecutive cultures of the specimens was taken three times from the same patients with one-week intervals (de Hoog et al 2000;Shemer et al 2009). …”

“…Traditionally nondermatophyte filamentous fungi have been considered as contaminant or secondary pathogens of the skin and nails; however, some of them may behave as primary pathogens (Bonifaz et al 2007;Iorizzo et al 2007). The prevalence of foot mycosis and onychomycosis by non-dermatophyte moulds among the population is still underestimated even if, in relation to the recent advances in diagnosis and risk factor identification, reports by the mycological medical community have increased (Iorizzo et al 2007;Shemer et al 2009). …”

Onychocola canadensis Sigler bei Onychomykose

“…Shemer et al [22] schlugen deshalb alternativ folgende Kriterien für die Diagnosesicherung einer Nagelinfektion durch NDM vor: Wenn ein Schimmelpilz nachgewiesen wird, sollte eine weitere Untersuchung von 3 separaten Nagelproben, die gleichzeitig zu entnehmen sind, erfolgen. Nur falls der Erreger in allen Kulturen nachgewiesen wird, ist die Infektion bestätigt, und es kann gezielt behandelt werden.…”

A Retrospective Study Comparing K101 Nail Solution as a Monotherapy and in Combination with Oral Terbinafine or Itraconazole for the Treatment of Toenail Onychomycosis

“…To determine the causative organism, nondermatophyte mold or Candida spp. were required to be cultured 3 times in the absence of dermatophytes [10]. The amount of infected and healthy nail was measured longitudinally in mm at baseline and at subsequent visits.…”