Frequency of Cutaneous Fungal Infections and Azole Resistance of the Isolates in Patients with Diabetes Mellitus

Clinic-mycological spectrum of Candida infection in diabetic foot ulcers in a tertiary care hospital

Background and Purpose

In diabetic foot ulcers, if fungal agents, such as Candida species penetrate the cutaneous or depth of the ulcer, it can increase the wound severity and make it more difficult to heal.

Materials and Methods

A cross-sectional study was performed on 100 diabetic patients with a foot ulcer from December 2019 to November 2020 in northern Iran. Patient data and wound grades were recorded in a questionnaire. Candida infection was confirmed by direct microscopic examination and culture. To identify the causative agent, polymerase chain reaction-restriction fragment length polymorphism using MspI enzyme and the partial amplification of hyphal wall proteins (HWP1) gene were performed.

Results

Mean age of the participants was 62.1 ± 10.8 years old, and 95% of them had type 2 diabetes. Moreover, more than 83% of them had diabetes for a duration of 10 years. In addition, 59% of the patients were male, and 66% > of them had poor education levels. Besides, 99% of them were married, and 52% were rural. Furthermore, 95% of the participants had neuropathic symptoms and 88% used antibiotics. The HbA1C level was > 9% in 69% of them, and the mean ulcer grade of the patients was 2.6±1.05. Candida infection was detected in 13% of the deep tissue and 7% of the tissue surrounding the wound. The predominant Candida isolate was C. parapsilosis (71.5%) and C. albicans (14.3%). Infections caused by filamentous fungi were not detected. There was a statistically significant relationship between Candida infection and gender, rural lifestyle, HbA1C, and ulcer grade.

Conclusion

Mycological evaluations of diabetic foot ulcers are often ignored. The present study revealed that C. parapsilosis is the most common causative agent of deep-seated foot ulcer infection in these patients and may require specific treatment. Therefore, more attention of physicians to Candida infections, early diagnosis, and prompt treatment can help accelerate wound healing and prevent amputation.

Biological macromolecules-based nanoformulation in improving wound healing and bacterial biofilm-associated infection: A review

A chronic wound is a serious complication associated with diabetes mellitus and is difficult to heal due to high glucose levels, oxidative stress, and biofilm-associated microbial infection. The structural complexity of microbial biofilm makes it impossible for antibiotics to penetrate the matrix, hence conventional antibiotic therapies became ineffective in clinical settings. This demonstrates an urgent need to find safer alternatives to reduce the prevalence of chronic wound infection associated with microbial biofilm. A novel approach to address these concerns is to inhibit biofilm formation using biological-macromolecule based nano-delivery system. Higher drug loading efficiency, sustained drug release, enhanced drug stability, and improved bioavailability are advantages of employing nano-drug delivery systems to prevent microbial colonization and biofilm formation in chronic wounds. This review covers the pathogenesis, microbial biofilm formation, and immune response to chronic wounds. Furthermore, we also focus on macromolecule-based nanoparticles as wound healing therapies to reduce the increased mortality associated with chronic wound infections.

Impact of the host microbiota on fungal infections: new possibilities for intervention?

Many human fungal pathogens are opportunistic. They are primarily benign residents of the human body and only become infectious when the host's immunity and microbiome are compromised. Bacteria dominate the human microbiome, playing an essential role in keeping fungi harmless and acting as the first line of defense against fungal infection. The Human Microbiome Project, launched by NIH in 2007, has stimulated extensive investigation and significantly advanced our understanding of the molecular mechanisms governing the interaction between bacteria and fungi, providing valuable insights for developing future antifungal strategies by exploiting the interaction. This review summarizes recent progress in this field and discusses new possibilities and challenges. We must seize the opportunities presented by researching bacterial-fungal interplay in the human microbiome to address the global spread of drug-resistant fungal pathogens and the drying pipelines of effective antifungal drugs.

Clinical Study of Coexistence of Fungal Infections in Diabetic Foot Ulcers by 18s rRNA Gene Polymerase Chain Reaction

BACKGROUND: Clinicians frequently ignore fungal infections in diabetic foot ulcers and do not regularly explore profound tissue from the injury for fungal culture and sympathy. AIM: The present study aimed to detect the etiologic substances and the regularity of fungal corruptions in ulcerated diabetic foot tissue samples utilizing two important diagnostic methods, namely, conventional microbiological methods and conventional 18s rRNA gene polymerase chain reaction (PCR) for detection of fungal foot infection. MATERIALS AND METHODS: One-hundred diabetic patients suffering from diabetic foot infections were enrolled in the present study. Deep tissue specimens from the depth of the wound were collected from the infected sites using aseptic techniques. Laboratory samples were examined, and morphophysiological methods identified pathogens to the species level. Fungi were detected in samples from infected sites using the PCR. RESULTS: The presence of fungal infection was detected in 17 (17%) of the 100 patients recruited in our study using conventional PCR. Conventional microbiological methods, on the contrary, revealed the presence of fungal infection in 14 patients (14%). Candida albicans was the most isolated pathogen (71%). CONCLUSION: In patients with chronic diabetic foot ulcers that are not responding to long-term antibiotic treatment, fungal pathogens should be considered. Early recognition of fungal corruptions in high-risk persons is serious for avoiding severe outcomes, that is, as foot amputation.

Fungal contamination of indoor public swimming pools and their dominant physical and chemical properties

Introduction

Considering the existence of both parasitic and fungal pathogens in the indoor public swimming pools and non-utilization of suitable filtration and disinfection systems in these places, this research aimed to determine the relationship between the indoor public swimming pools and possible pollution with parasitic and fungal agents, as well as physical and chemical characteristics of these pools and compare the results with national standards.

Methods

In this study, 11 active indoor swimming pools of Zahedan city were sampled, using plastic pump techniques, from the middle of winter to the late summer season. A total of 88 water samples (eight water samples from each pool) were examined to determine the residual chlorine, contamination with parasitic and fungal agents, using culture media and slide culture techniques. Results were analyzed with SPSS software (V16) and, Microsoft Excel (V2010).

Results

The findings revealed fungal contamination with Cladosporium, Penicillium, Aspergillus flavus and Aspergillus fumigatus, etc. and the physicochemical factors comply with the minimum standards, which indicates the need for continuous monitoring and control of water filtration and disinfection of water in the pools.

Conclusion

The results show reasonable derangement of physicochemical and microbial factors of the evaluated pools. Efforts shall be made by the concerned authorities to provide health education to users, quality water at the pools and to maintain the safety and quality of the water through proper and adequate chlorination.

Mycetoma due to Aspergillus flavus in a diabetic patient: Case report and literature review

Diabetes mellitus patients are prone to cutaneous and subcutaneous fungal infections due to pathogenic fungi, including dermatophytes, Mucorales, Candida, Aspergillus, and Fusarium species. Here, we report a case of A. flavus mycetoma confirmed by isolation and molecular identification. The case was a 38-year-old male farmer with a seven-year history of type 2 diabetes mellitus, living in Khuzestan, southwest of Iran. The patient presented with a right foot swelling associated with a nodule and multiple discharging sinuses following trauma sustained on the foot while working barefoot on the rice farm, a year ago. The nodule appeared at the site of the trauma two months after the injury. The initial diagnosis was based on direct microscopic examination of lesions scraping using 20% potassium hydroxide and radiology. Molecular analysis confirmed the isolates to be A. flavus. In vitro susceptibility of the isolate to voriconazole, posaconazole, caspofungin, itraconazole, and amphotericin B was determined. Treatment with voriconazole (200 mg twice daily) stopped the purulent discharge, reduced the swelling, and improved the clinical condition within two months. The study emphasizes the importance of wearing footwear to prevent skin trauma as the main risk factor of patient involvement.

Isolation and characterization of bacteria from diabetic foot ulcer: amputation, antibiotic resistance and mortality rate

Background

Diabetic foot ulcer (DFU) is one of the most serious complications of diabetes mellitus with devastating outcomes. Poorly treated DFU leads to osteomyelitis, gangrene and limb amputation. There is an increased risk of mortality for the amputees and increased number of bacterial resistance in survived patients. Struggle on choice of the best antibiotic(s) for DFU is escalating.

Objectives

To determine risk factors associated with mortality in patients with DFU. To investigate bacterial drug resistance in survived or deceased patients around amputation.

Methodology

This is a retrospective cohort study that involved all diabetic patients who had DFU or minor or major amputation at Hebron Governmental Hospital from 2013 to 2020. Antibiotic use and bacterial isolates along with culture and sensitivity test results were retrieved from patients' profiles and laboratory records. Major outcome of study was survival rate around amputation. Patients who missed test results for FBS or HbAc1, or who had no wound culture were excluded. SPSS version 22 was used to analyze data.

Results

Eighty four subjects were included in this study, 64.8 ± 12.58 years old, 63.1% males who had diabetic foot ulcer, minor or major limb amputation between 2013 and 2020 at Hebron Governmental Hospital. Forty tow patients (50%) had diabetic foot ulcer, 28 patients (33.3%) had major limb amputation, and 14 patients (16.7%), succumbed to minor amputation. Average FBS was 292.8 ± 136.33 mg/dl and average HbA1C was 8.55 ± 1.89%. Mortality rate was 9.5%. Using the Chi square test, we found a significant relationship between mortality and type of isolated bacteria, p = 0.033 and between diabetic complications (nephropathy) and mortality, p = 0.033. There was a significant relationship between antibiotic use and mortality, p = 0.04, especially with metronidazole and colistin, if they were used around limb amputation.

Conclusions

Mortality of diabetic patients with DFU was associated with nephropathy and Acinetobacter or E. coli infections.

Hemoptysis in a patient with pulmonary aspergilloma and type 2 diabetes mellitus: A rare case in an Indonesian adult

BACKGROUND

The success rate of surgery on aspergilloma is quite low since aspergilloma generally spreads throughout the lung cavity.

CASE PRESENTATION

A 45-year-old woman with a past history of type 2 diabetes mellitus presented with chronic hemoptysis. Clinical presentation and work up revealed a left lung aspergilloma, with x-ray and CT-scan showing a mass in the upper lobe of left lung and FNAB showing Aspergillus sp. The patient underwent thoracotomy with left superior lobectomy. Histopathological examination of specimens showed hyphae with septa. The patient had postoperatively controlled pleural effusions.

DISCUSSION

T2DM is a risk factor for Aspergillus sp infection because it is immunocompromised when hyperglycemia occurs. Pulmonary aspergilloma has a poor prognosis during surgery. Removing aspergilloma in the lung cavity and maintaining blood glucose levels can provide a good prognosis. Keeping the amount of fluid from increasing is the main focus of post-surgery.

CONCLUSION

Pulmonary aspergilloma that only occurs in one lung lobe has a good prognosis after surgery.

Candida albicans skin infection in patients with type 2 diabetes: a systematic review and meta-analysis

Background

Fungal infections including Candida albicans is one of the most important health concerns among type 2 diabetic patients. Therefore, this study aimed to determine the prevalence of C. albicans skin infection in patients with type 2 diabetes in a systematic review and meta-analysis.

Methods

In this review study, data were extracted from national and international databases of SID, MagIran, IranMedex, IranDoc, Google Scholar, Cochrane, Embase, ScienceDirect, Scopus, PubMed, and Web of Science (WoS) with no time limit until January 2021. The random effects model was used for doing analysis and the I² index was used for assessing the heterogeneity of studies. Data were analyzed using Comprehensive Meta-Analysis (Version 2).

Results

The prevalence of C. albicans skin infection in patients with type 2 diabetes was 11.4% (95% CI: 8.9%-14.4%) in 13 reviewed articles with a sample size of 1348. Regarding the heterogeneity based on meta-regression, there was a significant difference between the effect of sample size (P < 0.05) and the prevalence of C. albicans skin infection in patients with type 2 diabetes.

Conclusion

The results of this study showed that C. albicans skin infection was high in type 2 diabetic patients in Iran. Therefore, to improve the aforementioned situation and to troubleshoot and monitor at all levels, appropriate policies should be adopted.

Infections associated with diabetic-care devices

BACKGROUND AND AIMS

There are more than 463 million people living with diabetes with this number expected to increase to 700 million people by 2045. Diabetes is a risk factor for patients developing various comorbidities including, but not limited to, diabetic neuropathy, retinopathy, chronic kidney disease, vascular impediments, and infections. Due to the continuous invasiveness of monitoring and/or treatment of this disease, site for infections are elevated.

METHODS

Information was primarily gathered by employing various PubMed scholarly articles for real-world examples in addition to data extraction from supplementary manuscripts. Key search words employed were: diabetes, insulin site infection, lancing infections, insulin pump associated infections, and continuous glucose monitoring infections.

RESULTS

Diabetic care devices used for blood glucose monitoring and insulin administration are an integral part of the disease management and/or treatment in various settings including patient homes, assisted living facilities, community centers, and hospitals. These invasive devices leave a diabetic patient with a small open wound which may get infected or aid in blood borne pathogen transmission. Since diabetes itself has a morbidity and mortality burden, it is important to also study complications arising from the management of diabetes.

CONCLUSION

Although cases exist of infections, either by pathogen transmission or direct inoculation of the prick site, these are a very small percentage and thus should not undermine the confidence in diabetes management. This review highlights the instances of these infections and where they most often occur.

Genotypic and Phenotypic Changes in Candida albicans as a Result of Cold Plasma Treatment

We treated Candida albicans cells with a sublethal dose of nonequilibrium (cold) atmospheric-pressure He plasma and studied alterations in the genome of this fungus as well as changes in the phenotypic traits, such as assimilation of carbon from carbohydrates, hydrolytic enzyme activity, and drug susceptibility. There is a general problem if we use cold plasma to kill microorganism cells and some of them survive the process—whether the genotypic and phenotypic features of the cells are significantly altered in this case, and, if so, whether these changes are environmentally hazardous. Our molecular genetic studies have identified six single nucleotide variants, six insertions, and five deletions, which are most likely significant changes after plasma treatment. It was also found that out of 19 tested hydrolytic enzymes, 10 revealed activity, of which nine temporarily decreased their activity and one (naphthol-AS-BI- phosphohydrolase) permanently increased activity as a result of the plasma treatment. In turn, carbon assimilation and drug susceptibility were not affected by plasma. Based on the performed studies, it can be concluded that the observed changes in C. albicans cells that survived the plasma action are not of significant importance to the environment, especially for the drug resistance and pathogenicity of this fungus.

Adherence and Cytotoxicity of Candida spp. to HaCaT and A549 cells

Candida species are opportunistic fungal pathogens that cause superficial or invasive infections. Recently, the incidence of infection by non-Candida albicans species, especially Candida glabrata, has increased. In this study, we analyzed the adhesion and cytotoxicity of various Candida spp. that are part of the normal human microbiota. C. albicans adheres well to cell culture plates and to cultured cells. C. glabrata selectively adheres to epithelial cells rather than to cell culture plates. Candida parapsilosis insufficiently adheres to confluent monolayers of human lung epithelial A549 and keratinocyte HaCaT cells. We then analyzed the cytotoxicity of C. albicans and C. glabrata, which adhered well to epithelial cells. C. glabrata has been found to cause more damage to A549 cells than to HaCaT cells, suggesting that resident Candida spp. have distinct cytotoxic effects in different tissues. It is important to clarify the properties of Candida spp. as there is evidence that normal microbiota can cause infections. Our data suggest that it is necessary to use appropriate cell lines for characterizing the adherence and cytotoxicity of Candida spp.

A neglected causative agent in diabetic foot infection: a retrospective evaluation of 13 patients with fungal etiology

Background/aim

Clinicians often neglect fungal infections and do not routinely investigate deep tissue from the wound for fungal culture and sensitivity due to insufficient information in the literature. In this study, we aimed to evaluate fungal etiology of invasive fungal diabetic foot which is rarely reported in the literature.

Materials and methods

The patients who were unresponsive to antibiotic therapy and those with positive fungal in bone or deep tissue culture were enrolled in the study. Detailed hospital records were retrieved for demographics and clinical features.

Results

A total of 13 patients who were diagnosed with invasive fungal diabetic foot (ten females, three males, mean age 59.8 ± 9 years) were included. All of the patients had type-2 diabetes mellitus. Eleven (84.6%) patients had mixed infection. The most common cause of fungal infections of diabetic foot ulcers was the Candida species. Ten (76.9%) patients underwent amputation, two (15.4%) patients refused amputation, and one patient died before surgery.

Conclusion

Invasive fungal infections may also be a causative pathogen in deep tissue infections. Therefore, fungal pathogens should be considered in patients unresponsive to long-term antibiotic therapy. Early detection of fungal infections in high-risk individuals is critical for the prevention of severe consequences such as foot amputation.

Candida sp. Infections in Patients with Diabetes Mellitus

Candidiasis has increased substantially worldwide over recent decades and is a significant cause of morbidity and mortality, especially among critically ill patients. Diabetes mellitus (DM) is a metabolic disorder that predisposes individuals to fungal infections, including those related to Candida sp., due to a immunosuppressive effect on the patient. This review aims to discuss the latest studies regarding the occurrence of candidiasis on DM patients and the pathophysiology and etiology associated with these co-morbidities. A comprehensive review of the literature was undertaken. PubMed, Scopus, Elsevier’s ScienceDirect, and Springer’s SpringerLink databases were searched using well-defined search terms. Predefined inclusion and exclusion criteria were applied to classify relevant manuscripts. Results of the review show that DM patients have an increased susceptibility to Candida sp. infections which aggravates in the cases of uncontrolled hyperglycemia. The conclusion is that, for these patients, the hospitalization periods have increased and are commonly associated with the prolonged use of indwelling medical devices, which also increase the costs associated with disease management.

The synergistic fungicidal effect of low-frequency and low-intensity ultrasound with amphotericin B-loaded nanoparticles on C. albicans in vitro

It is difficult to effectively eradicate C. albicans using traditional antifungal agents, mainly because the low permeability of the C. albicans cell wall creates strong drug resistance. The aim of this study was to investigate the synergistic fungicidal effect and the underlying mechanisms of low-frequency and low-intensity ultrasound combined with a treatment of amphotericin B-loaded nanoparticles (AmB-NPs) against C. albicans. AmB-NPs were prepared by a poly(lactic-co-glycolic acid) (PLGA) double emulsion method. C. albicans was treated by AmB-NPs combined with 42 kHz ultrasound irradiation at an intensity of 0.30 W/cm² for 15 min. The results demonstrate that the application of ultrasound enhanced the antibacterial effectiveness of AmB-NPs (P < 0.01), and the antifungal efficiency increased significantly with increasing AmB concentration of drug-loaded nanoparticles under ultrasonic irradiation. Additionally, the mycelial morphology of C. albicans suffered from the most severe damage and loss of normal microbial morphology after the combined treatment of AmB-NPs and ultrasound, as revealed by electron microscope. Furthermore, we verified the safe use of low-frequency ultrasound on exposed skin and discussed the potential mechanism of ultrasound enhanced fungicidal activity. The results reveal that the mechanism may be associated with the ultrasound cavitation effect and an increase in intracellular reactive oxygen species.

NSG2 (ORF19.273) Encoding Protein Controls Sensitivity of Candida albicans to Azoles through Regulating the Synthesis of C14-Methylated Sterols

Antifungal azole drugs inhibit the synthesis of ergosterol and cause the accumulation of sterols containing a 14α-methyl group, which is related to the properties of cell membrane. Due to the frequent recurrence of fungal infections and clinical long-term prophylaxis, azole resistance is increasing rapidly. In our research, Nsg2p, encoded by the ORF19.273 in Candida albicans, is found to be involved in the inhibition of 14α-methylated sterols and resistance to azoles. Under the action of fluconazole, nsg2Δ/Δ mutants are seriously damaged in the integrity and functions of cell membranes with a decrease of ergosterol ratio and an increase of both obtusifoliol and 14α-methylfecosterol ratio. The balance between ergosterol and 14α-methyl sterols mediated by NSG2 plays an important role in C. albicans responding to azoles in vitro as well as in vivo. These phenotypes are completely different from those of Nsg2p in Saccharomyces cerevisiae, which is proved to increase the stability of HMG-CoA and resistance to lovastatin. Based on the evidence above, it is indicated that the decrease of 14α-methylated sterols is an azole-resistant mechanism in C. albicans, which may provide new strategies for overcoming the problems of azole resistance.