Identification of gentian violet concentration that does not stain oral mucosa, possesses anti-candidal activity and is well tolerated

Successful treatment of experimental murine vulvovaginal candidiasis with gentian violet

Aim: This study evaluated the antifungal efficacy of gentian violet (GV) in an experimental vulvovaginal candidiasis (VVC) model. Materials & methods: In vitro susceptibility and cytotoxicity assays were performed to validate the antifungal potential and safety of GV. The antifungal efficacy was then evaluated in vivo through comparative analysis of the fungal burden following treatment with GV or nystatin, as well as assessment of the vaginal tissue by histology and electron microscopy. Results: GV demonstrated a safe antifungal profile against C. albicans, with a significant decrease in fungal burden and an improvement in the inflammatory process evaluated histologically. Conclusion: The results of this study motivate further assessment of GV as a promising alternative for VVC therapy.

Synergistic interactions of cadmium-free quantum dots embedded in a photosensitised polymer surface: efficient killing of multidrug-resistant strains at low ambient light levels

Cadmium-free quantum dots (QD) were combined with crystal violet photosensitising dye and incorporated into medical grade polyurethane via a non-covalent dipping process known as 'swell-encapsulation-shrink'. The antibacterial efficacy of the prepared quantum dot-crystal violet polyurethane substrates (QD + CV PU) was investigated under low power visible light illumination at similar intensities (500 lux) to those present in clinical settings. The antibacterial performance of QD + CV PU was superior to the constituent polymer substrates, eliminating ∼99.9% of an environmental P. aeruginosa strain, a clinical P. aeruginosa strain from a cystic fibrosis patient and a clinical E. coli strain. The nature of the reactive oxygen species (ROS) involved in antibacterial activity of the QD + CV PU surface was investigated using ROS inhibitors and time-resolved optical spectroscopy. The photo-physical interactions of the green-emitting QDs with CV lead to a combination of Type I and II electron transfer and energy transfer processes, with the highly potent ROS singlet oxygen playing a dominant role. This study is the first to demonstrate highly efficient synergistic killing of clinical and environmental strains of intrinsically resistant and multi-drug resistant Gram-negative bacteria using light-activated surfaces containing biocompatible cadmium-free QDs and crystal violet dye at ambient light levels.

Oral fungi in HIV: challenges in antifungal therapies

Oral candidiasis (OC) caused by Candida species is a common fungal infection among HIV-infected individuals. Despite the wide use of antiretroviral therapy (ART) resulting in a declined prevalence, OC remains the most common oral lesions seen in those living with HIV/AIDS. Various topical and systemic antifungal drugs are available to treat OC. However, due to the patients' immunodeficiency and the nature of OC as biofilm-associated infection, relapse is frequently observed after cessation of antifungal therapy. In addition, long-term antifungal therapy may lead to drug resistance. This review article addressed three major challenges in the treatment of OC in HIV infection including antifungal drug resistance, biofilm-associated infection of OC, and the host underlying immunodeficiency. To reduce the risks of antifungal drug resistance, the author recommends that future studies should focus on herbal plant-derived compounds with antifungal activity that may be used in combination with the drugs. Also, it is recommended that more research should be carried out to explore how to enhance the host innate immunity against oral Candida.

Oral shedding of herpesviruses in HIV-infected patients with varying degrees of immune status

OBJECTIVE

Herpesvirus shedding in the oral cavity was analyzed to determine if presence in the oral compartment correlates with systemic changes in HIV-associated immune deficiency as measured by CD4 cell counts, plasma HIV viral load and presence of AIDS-defining events.

DESIGN

A5254 is a multicenter, cross-sectional, single-visit study to evaluate oral complications of HIV/AIDS and determine the association between clinical appearance, herpesvirus shedding, and immune status as ascertained by CD4 cell count and HIV viral load. In total, 307 HIV-infected individuals were evaluated and throat wash collected.

METHODS

Fisher's exact test and Kruskal-Wallis test were used to assess the association between presence of herpesviruses and the state of immunodeficiency as stratified by a combination of CD4 cell count and HIV viral load. Relationship between pathogens and HIV viral load in plasma was modeled by logistic regression.

RESULTS

The presence of cytomegalovirus (CMV) and herpes simplex virus-1 in throat wash was associated with decreased CD4 cell counts. By contrast, Kaposi sarcoma-associated herpesvirus and Epstein-Barr virus were similarly detectable across all levels of CD4 cell counts. One unit increase in log10 (HIV viral load) was associated with 1.31 times higher odds of detecting CMV in throat wash when controlling for oral candidiasis, CD4 cell count, and sites (95% confidence interval 1.04-1.65, P = 0.02).

CONCLUSION

Oral CMV shedding was significantly higher in highly immunocompromised HIV participants. Our finding supports the recommendations to start antiretroviral therapy independent of CD4 cell count as this may have the added benefit to lower the risk of herpesvirus transmission among persons infected with HIV and their partners.

Topical gentian violet compared with nystatin oral suspension for the treatment of oropharyngeal candidiasis in HIV-1-infected participants

OBJECTIVE

Compare the safety and efficacy of topical gentian violet with that of nystatin oral suspension (NYS) for the treatment of oropharyngeal candidiasis in HIV-1-infected adults in resource-limited settings.

DESIGN

Multicenter, open-label, evaluator-blinded, randomized clinical trial at eight international sites, within the AIDS Clinical Trials Group.

STUDY PARTICIPANTS AND INTERVENTION

Adult HIV-infected participants with oropharyngeal candidiasis, stratified by CD4 cell counts and antiretroviral therapy status at study entry, were randomized to receive either gentian violet (0.00165%, BID) or NYS (500 000 units, QID) for 14 days.

MAIN OUTCOME MEASURE(S)

Cure or improvement after 14 days of treatment. Signs and symptoms of oropharyngeal candidiasis were evaluated in an evaluator-blinded manner.

RESULTS

The study was closed early per Data Safety Monitoring Board after enrolling 221 participants (target = 494). Among the 182 participants eligible for efficacy analysis, 63 (68.5%) in the gentian violet arm had cure or improvement of oropharyngeal candidiasis versus 61 (67.8%) in the NYS arm, resulting in a nonsizable difference of 0.007 (95% confidence interval: -0.129, 0.143). There was no sizable difference in cure rates between the two arms (-0.0007; 95% confidence interval: -0.146, 0.131). No gentian violet-related adverse events were noted. No sizable differences were identified in tolerance, adherence, quality of life, or acceptability of study drugs. In gentian violet arm, 61 and 39% of participants reported 'no' and 'mild-to-moderate' staining, respectively. Cost for medication procurement was significantly lower for gentian violet versus NYS (median $2.51 and 19.42, respectively, P = 0.01).

CONCLUSION

Efficacy of gentian violet was not statistically different than NYS, was well tolerated, and its procurement cost was substantially less than NYS.

Anti-candidal activity of a novel peptide derived from human chromogranin A and its mechanism of action against Candida krusei

Candida species (Candida spp.) are important fungal pathogens, which cause numerous clinical diseases associated with significant mortality and morbidity in healthcare settings. In our previous study, we identified a recombinant peptide, chromogranin A (CGA)-N46, corresponding to the N-terminal Pro31-Gln76 sequence of human CGA, that exhibited antifungal activity against Candida albicans. The present study investigated the antifungal activity of CGA-N46, and its underlying mechanism, against numerous Candida spp. CGA-N46 inhibited the growth of all of the tested Candida spp., of which Candida krusei exhibited the greatest sensitivity. CGA-N46 was able to disrupt the stability of the phospholipid monolayer without damaging the integrity and permeability of the outer membrane of C. krusei cells, and induced cytoplasm vacuolization and mitochondrial damage. In addition, treatment of C. krusei with CGA-N46 was associated with decreased levels of intracellular reactive oxygen species, a reduction in the mitochondrial membrane potential, and DNA synthesis inhibition. The results of the present study suggested that CGA-N46 was able to pass through the cell membrane of Candida spp. by temporarily destabilizing the phospholipid membrane, which in turn led to mitochondrial dysfunction and inhibition of DNA synthesis. Therefore, CGA-N46 may be considered a novel antifungal compound for the treatment of patients with C. krusei infections.