Dermatological manifestations of fungal infection in patients with febrile neutropaenia: A review of the literature

Molecular diagnosis, phylogenetic analysis, and antifungal susceptibility profiles of Candida species isolated from neutropenic oncological patients

BACKGROUND

Neutropenia is the most important cause of life-threatening invasive fungal infections (IFIs). Here, we studied the frequency and antifungal susceptibility profiles of Candida species that colonized or caused infections among neutropenic patients with solid or hematological malignancies.

METHODS

A total of 362 clinical samples were collected from 138 patients. After initial isolation using a mix of mycological methods, isolates were screened using chromogenic culture media. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was applied for molecular identification. Positive or suspected cases were confirmed using the reference method of sequencing. Antifungal susceptibility testing for voriconazole and caspofungin was carried out using the microbroth dilution method. An in-silico assay was applied for phylogenetic analysis.

RESULTS

Thirty-four Candida strains were isolated. C. albicans (47.06%) and C. glabrata (29.41%) were the most frequent strains. Antifungal treatment reduced the chance of Candida colonization by almost 76% in neutropenic patients (OR: 1.759; 95% CI: 1.349 to 2.390; p value: 0.000). An unusual and non-resistant strain, C. lambica, was reported from the bloodstream of a 56-year-old man with hematologic malignancy (HM). Eight isolates were non-susceptible, and one isolate was resistant to voriconazole. Also, four isolates were non-susceptible to caspofungin.

CONCLUSION

We can conclude that there is a cause-and-effect relationship between neutropenia, HM background, and Candida species separated from neutropenic patients, which can lead to possible infections. Further and repetitive studies are recommended using different molecular methods for better prediction and management of fungal infections in neutropenic patients.

Discovery of Novel Thiosemicarbazides Containing 1,3,5-Triazines Derivatives as Potential Synergists against Fluconazole-Resistant Candida albicans

The clinical prevalence of antifungal drug resistance has been increasing over recent years, resulting in the failure of treatments. In an attempt to overcome this critical problem, we sought novel synergistic enhancers to restore the effectiveness of fluconazole against resistant Candida albicans. Based on the structural optimization of hit compound 8 from our in-house library, a series of novel 1,3,5-triazines derivatives was designed, synthesized, and biologically evaluated for synergistic activity in combination with fluconazole. Among them, compounds 10a-o, which contain thiosemicarbazides side chains, exhibited excellent in vitro synergistic antifungal potency (MIC80 = 0.125-2.0 μg/mL, FICI range from 0.127 to 0.25). Interestingly, compound 10l exhibited moderate C. albicans activity as monotherapy with an MIC80 value of 4.0 μg/mL, and also on several Cryptococcus strains (MIC80 ranging from ≤ 0.125-0.5 μg/mL) and C. glabrata (MIC80 ≤ 0.125 μg/mL). These effects were fungal-selective, with much lower levels of cytotoxicity towards human umbilical vein endothelial cells. Here, we report a series of thiosemicarbazides containing 1,3,5-triazines derivatives as potent synergists with fluconazole, and have preliminarily validated compound 10l as a promising antifungal lead for further investigation.

A global view on fungal infections in humans and animals: opportunistic infections and microsporidioses

After cardiovascular diseases, infectious diseases are the second most common cause of death worldwide. Although these infections are caused mainly by viruses or bacteria, a systematically growing prevalence of human and animal opportunistic fungal infections is noticeable worldwide. More attention is being paid to this problem, especially due to the growing frequency of recalcitrant and recurrent mycoses. The latter are classically divided into superficial, which are the most common type, subcutaneous, and systemic. This work discusses opportunistic fungal pathogens without proven horizontal transmission between different animal species including humans and microsporidia as spore-forming unicellular parasites related to fungi; however, with a yet undetermined taxonomic position. The review also mentions aetiological agents, risk factors, epidemiology, geographical distribution, and finally symptoms characteristic for individual disease entities. This paper provides insight into fungal infections from a global perspective and simultaneously draws attention to emerging pathogens, whose prevalence is continuously increasing. Finally, this work also takes into consideration the correct nomenclature of fungal disease entities and the importance of secondary metabolites in the pathogenesis of fungal infections.

Antimicrobial activities of Asian ginseng, American ginseng, and notoginseng

Asian ginseng (Panax ginseng C.A. Meyer), American ginseng (Panax quinquefolius) and notoginseng (Panax notoginseng) are the three most commonly used ginseng botanicals in the world. With the increasing interests on antimicrobial properties of plants, the antimicrobial activities of ginseng species have been investigated by a number of researchers worldwide. This overview interprets our present knowledge of the antimicrobial activities of the three ginseng species and some of their bioactive components against pathogenic bacteria (Pseudomonas aeruginosa, Helicobacter pylori, Staphylococcus aureus, Escherichia coli, Propionibacterium acnes, et al.) and fungi (Candida albicans, Fusarium oxysporum, et al). Ginsenosides, polysaccharides, essential oil, proteins, and panaxytriol are all might responsible for the antimicrobial activities of ginseng. The antimicrobial mechanisms of ginseng components could be summarized to the following points: (a) inhibit the microbial motility and quorum-sensing ability; (b) affect the formation of biofilms and destroy the mature biofilms, which can weaken the infection ability of the microbes; (c) perturb membrane lipid bilayers, thus causing the formation of pores, leakages of cell constituents and eventually cell death; (d) stimulate of the immune system and attenuate microbes induced apoptosis, inflammation, and DNA damages, which can protect or help the host fight against microbial infections; and (e) inhibit the efflux of antibiotics that can descend the drug resistance of the microbial. The collected information might facilitate and guide further studies needed to optimize the use of ginseng and their components to improve microbial food safety and prevent or treat animal and human infections.