Molecular and Histological Association Between Candida albicans from Oral Soft Tissue and Carious Dentine of HIV-Positive Children

Abstract

Abstractand caries are frequently investigated among healthy and immunosuppressed individuals. The objective of this study was to demonstrate the presence of on both oral soft and hard tissue and to investigate, at molecular level, the genetic subtype of the organism from the two oral sites. Tongue swabs and dentine scrapings from 362 HIV-positive children, referred for extraction of carious primary teeth, were cultured on CHROMagar and identified to species level with ID32C. Histological staining of extracted carious teeth was also done. In patients with positive cultures from both the tongue and carious dentine, DNA fingerprinting of such paired isolates were performed, using Southern blot hybridisation with the Ca3 probe. Yeasts were cultured from the tongue of 151 (41.7%) individuals and 57 (37.7%) simultaneously yielded positive cultures from carious dentine. Nine different yeast spp. were identified from the tongue using the ID32C commercial system but was the only species recovered from carious dentine and histological investigation demonstrated fungal elements penetrated into the dentine and not limited to superficial debris on the floor of the cavity. Twelve of 13 paired isolates of revealed identical fingerprinting patterns. The findings from this study demonstrated that in a particular individual, the same genetic subtype of was capable of colonizing both oral soft tissue and carious dentine. This renders carious teeth a constant source, or reservoir, of potentially infectious agents and, particularly among immunosuppressed individuals, should therefore not be left unattended.

Oral mycobiome identification in atopic dermatitis, leukemia, and HIV patients – a systematic review

“… IgG-levels in sera from AD patients were significantly lower than in controls. Colorimetric and morphological identification; molecular method (PCR) C. parapsilosis C. albicans C. glabrata C. dubliniensis Blignaut et al South Africa 2015 [ 72 ] To demonstrate C. albicans presence in soft and hard tissues and to investigate by molecular techniques the genetic subtype from two different oral sites. Decayed teeth can be considered potential C. albicans reservoirs, and they can cause infection in immunocompromised patients.…”

“…Among these techniques, the most widely used are the sugar fermentation and assimilation tests, which currently have several commercial kits that have facilitated and disseminated their use in laboratories such as API20 C AUX (Biomérieux®), which is one of the most used commercial systems for the identification of yeasts [ 71 ]. The articles that used commercial kits to identify the most common Candida species were: Das Chagas et al [ 50 ]; Junqueira et al [ 51 ]; Mane et al [ 70 ]; Merestein et al [ 55 ]; Li et al [ 47 ]; Jiang et al [ 57 ]; Thanyasrisung et al [ 58 ]; Blignaut and van Heerden [ 72 ]; Menezes et al [ 59 ]; Lourenço et al [ 60 ]; and Vijendran et al [ 46 ]. Mushi et al [ 73 ] was the only work that used MS focused on microbiology to identify fungi.…”

“…Culture media are an example of morphological techniques that can be used to identify and distinguish species [93]. This study demonstrated that despite presenting limitations, morphological techniques such as colorimetric identification CHROMagar® as well as the germ tube test are still widely used prior to the molecular techniques [36,52,56,72]. In this case, molecular techniques were used after these morphological analyses in order to confirm the species identified at the molecular level because the mycological identification of species becomes necessary when the investigated patient is already immunocompromised [68].…”

“…Blignaut and van Heerden [72] was the only work that made use of DGGE which is an excellent tool to assess previously unknown microbial diversity [105]. Using this technique, the authors were able to see that colonization of oral soft tissue and dentin is done by the same genetic subgroup of C. albicans [81].…”

Candidiasis - has anything changed in the way we manage these patients?

“…Wherever possible carious teeth with exposed dentine should be restored or removed if effective resolution of oral candidiasis is to be achieved, particularly if an underlying medical condition or immunosuppression prevails in patients. 31 Despite the topical application of an aqueous oral solution of nystatin having been proven ineffective as both a prophylactic and therapeutic agent, it continues to be prescribed to adults. 18 While nystatin itself has been shown to have some efficacy, it is probable that the aqueous solution/suspension does not provide for the antifungal to remain in contact with the mucosa for sufficient periods of time.…”