PREVENTION OF CANDIDIASIS IN PATIENTS USING REMOVABLE DENTURES

Background: Despite innovations in orthopedic dentistry, the manufacture of removable dentures belongs to the most popular orthopedic care category. Removable dentures are combined stimuli that affect the mucous membrane and neuro-receptor apparatus. Acrylic plastic prostheses, widely used in prosthetic dentistry, have a negative side mechanical, chemical-toxic, sensitizing, and thermal insulating effect on oral tissue and prosthetic impression area. This is often complicated by a violation of the biocenosis of the oral cavity, the growth of pathogenic microflora that releases toxins, especially an increase in the number of yeast colonies that irritate the oral mucosa and prosthetic stomatitis. According to the WHO, one-fifth of the world s population suffers or has suffered various candidiasis forms at least once. The worldwide increase in the incidence of the disease is primarily related to the fact that this infection is opportunistic, more than half of the world s population is a carrier of fungi of this kind, i.e., in most cases, it is an endogenous infection, which makes candidiasis different from other opportunistic mycoses. Aims: The purpose of this study was to study the prevalence of candidiasis in patients using removable dentures and to evaluate the effectiveness and prevention of candidiasis treatment. Methods: 100 patients with oral candidiasis of various age groups from 45 to 65 years were observed. Of these, 60 patients with removable plate prostheses; 40 patients with partially removable prostheses. Results and Discussion: Chronic forms of candidiasis were diagnosed in 40 patients and with exacerbation of chronic forms of candidiasis-60 people. The number of untreated carious cavities and poor hygienic condition of the oral cavity directly affects the severity of candidiasis. Acute forms of candidiasis were observed mainly in patients with high DMF and PMA indices. The severity of candidiasis depends on the degree and duration of wearing dentures and hygienic conditions - the most severe forms of invasive candidiasis were observed in the presence of removable plate prostheses, the complete absence of teeth, and the use of a prosthesis for more than 10-15 years. A combined lesion of the oral mucosa and the red border of the lips was observed mainly in patients older than 60 years. Conclusions: The presence of candidiasis in the oral cavity in patients with removable plate prostheses leads to a statistically significant change in the indicators of local immunity of the oral cavity: an increase in the concentration of serum IgG and IgA and the values of the coefficient of the balance of local immunity factors.

New Applications of Photodynamic Therapy in the Management of Candidiasis

The most important aetiological agent of opportunistic mycoses worldwide is Candida spp. These yeasts can cause severe infections in the host, which may be fatal. Isolates of Candida albicans occur with greater frequency and variable resistance patterns. Photodynamic therapy (PDT) has been recognised as an alternative treatment to kill pathogenic microorganisms. PDT utilises a photosensitizer, which is activated at a specific wavelength and oxygen concentration. Their reaction yields reactive oxygen species that kill the infectious microorganism. A systematic review of new applications of PDT in the management of candidiasis was performed. Of the 222 studies selected for in-depth screening, 84 were included in this study. All the studies reported the antifungal effectiveness, toxicity and dosimetry of treatment with antimicrobial PDT (aPDT) with different photosensitizers against Candida spp. The manuscripts that are discussed reveal the breadth of the new applications of aPDT against Candida spp., which are resistant to common antifungals. aPDT has superior performance compared to conventional antifungal therapies. With further studies, aPDT should prove valuable in daily clinical practice.

SARS CoV-2 VIRUS Vs OPPORTUNISTIC MYCOSES

Purpose: SARS CoV 2 virus a novel coronavirus, which is a single stranded positive sense RNA virus. It causes severe pneumonia in susceptible individuals. In individuals with predisposing factors, like diabetes, neutropenia, corticosteroids therapy, and etc., the virus causes opportunistic fungal infections. This study aims the correlation between COVID 19 disease and fungal infections. Methodology: The present study includes 202 specimens collected from patients with symptoms suspected of fungal infections. The collected specimens were subjected to direct microscopy and fungal culture. Results: Nasal tissue scrapings were the most common specimen collected followed by sputum. Among the 202 specimens collected, 106 were positive for direct microscopy and 81 were positive for fungal culture. Conclusion: The fungal infections are more common among the patients with comorbidities, and appropriate guidelines should be followed in the management of such infections in order to prevent the morbidity and the mortality.

MODERN MICROBIOLOGICAL TECHNOLOGIES IN DIAGNOSIS OF MYCOSES IN OTORHINOLARYNGOLOGICAL PRACTICE

The review article highlights the latest approaches to solve one of the important problems of modern otorhinolaryngology, the diagnosis of opportunistic mycoses of the upper respiratory tract and ear. Opportunistic mycoses of the ENT organs in recent decades have posed a significant challenge for modern clinical medicine not only in Ukraine but also throughout the world. According to the scientific literature, the share of fungal lesions of the ear and upper respiratory tract in the structure of chronic inflammation of these organs makes up 22.1%. The main causative agents of mycotic lesions of the ENT organs are opportunistic fungi of the genera Aspergillus, Рenicillium, Mucor and yeast-like fungi of the genus Сandida, which are characterized by a low level of pathogenicity and are a part of the resident microflora of the macroorganism. Classical methods of microbiological diagnosis have certain limitations in the identification of micromycetes. Therefore, the use of more reliable, fast and accurate methods in clinical practice will contribute to the timely and effective treatment of fungal diseases of the ENT organs. This review presents an analysis of modern microbiological diagnostic technologies, such as biochemical detection of microorganisms using identification plate test systems (ARI RapID, CrystalTM), semi-automatic and automatic microbiological identification using analyzers VITEK, VITEK 2, Walk Away. Identification of fungal pathogens can also be performed by performing direct protein profiling using mass spectrometry, polymerase chain reaction and sequencing. These methods with the highest level of reliability enable to identify the pathogen, as well as to assess its sensitivity to chemotherapeutic drugs. The combination of classical and modern microbiological technologies should become a standard for the diagnosis of fungal diseases, including the upper respiratory tract and ear.

Mucormycosis in a liver allograft after liver transplantation for secondary biliary cirrhosis due to bile duct injury

Introduction: Mucormycosis refers to a group of opportunistic mycoses that occur generally in immunocompromised patients and are caused by Mucorales, ubiquitous filamentous fungi with broad, thin-walled, sparsely septate, ribbon-like hyphae. Case report: A 57-year-old man with a history of secondary biliary cirrhosis due to inadvertent bile duct injury during cholecystectomy. He was referred to our center and underwent LT on June 2018. Due to severe coagulopathy he underwent exploratory laparotomy and abdominal packing for 48 hours. He recovered with good liver function and LFT´s with a tendency towards normalization. On post op day 8 the patient presented an episode of fever and a CT scan was performed showing a large zone of hypoperfusion with bubbles of gas in the liver dome. A percutaneous biopsy was taken for cultures. Preliminary results reported a filamentous fungus and liposomal amphotericin b was initiated with the suspicion of mucormycosis. The patient remained afebrile and asymptomatic. After 5 days of treatment a new image was performed, and progression of the lesion was noticed, due to these findings the patient was taken to the OR for surgical debridement. Involvement of the liver dome and diaphragm was noticed and a non-anatomic hepatectomy was performed. After surgery the patient required increasing amounts of vasopressors. Despite all the support he progressed to multiple organic failure and finally expired. The product of hepatectomy confirmed the diagnosis of mucormycosis (Rhizopus sp). Discussion: Despite all the efforts the patients’ clinical condition deteriorated after surgery showing the high mortality rate in liver transplant recipients that has been reported of 50 to 100%.

Opportunistic Soil-Inhabiting Micromycetes during Monitoring Analysis of Agrocenoses

Под влиянием антропогенных факторов в почве и сопряжённых с нею средах может происходить накопление опасных для человека (потенциально патогенных, аллергенных, микотоксичных) видов микроскопических грибов. Изучение этой группы микромицетов и явилось целью настоящей работы. Представлены результаты исследований, проведённых в 2011–2018 гг. в полевом стационарном опыте, заложенном на опытном поле ФГБОУ ВО Ярославская ГСХА, по изучению различных систем обработки почвы и систем удобрений. В 2014–2015 гг. дополнительно исследовали почву зоны перелеска, заросшей грунтовой дороги и леса по краю поля, которые представляют собой естественно сформировавшиеся растительные ассоциации. Многие из обнаруженных нами почвообитающих грибов как в естественных сообществах, так и в окультуренной почве, являются потенциально-патогенными видами, относящимися к III и IV группам по классификации санитарно-эпидемиологических правил СП 1.3.2322-08. Полученные результаты не выявили общих закономерностей распространения оппортунистических грибов в исследованной почве. Однако в целом большинство из них не имеют широкого распространения по частоте встречаемости и массовости. Исключением являются виды р. Aspergillus. Как аллергенные, в первую очередь, рассматриваются виды тёмноокрашенных родов Alternaria (A. alternata), Cladosporium (C. herbarum), а также рода Aspergillus (A. flavus, A. fumigatus, A. niger). По мнению ряда авторов, в настоящее время увеличилась распространённость сапротрофных видов грибов, способных продуцировать микотоксины и вызывать микотоксикозы и оппортунистические микозы. В связи с этим необходим постоянный мониторинг фитосанитарной ситуации в посевах сельскохозяйственных культур, тщательный микологический и микотоксикологический контроль сельскохозяйственной продукции, совершенствование видовой диагностики грибов. Under the influence of anthropogenic factors the accumulation of types of microscopic fungi that are dangerous for humans (potentially pathogenic, allergenic, mycotoxic) can occur in soil and its associated medium. The study of this group of micromycetes was the aim of this work. The results of the researches conducted in 2011–2018 in the stationary test laid down on the experimental field of the FSBEI HE Yaroslavl State Agricultural Academy to study various tillage systems and fertilizer systems are presented. In 2014–2015 the soil of the field woodland zone, overgrown dirt road and forest along the edge of the field which are naturally formed plant associations was additionally investigated. Many of the soil fungi found by us both in natural communities and in cultivated soil are potentially pathogenic species belonging to groups III and IV according to the classification of sanitary and epidemiological rules SP 1.3.2322-08. The results obtained did not reveal the general patterns of the spread of opportunistic fungi in the soil under investigation. However in general most of them are not widespread in frequency of occurrence and massive participation. An exception is the species g. Aspergillus. As allergenic, first of all species of the dark-colored genus Alternaria (A. alternata), Cladosporium (C. herbarum), and also the genus Aspergillus (A. flavus, A. fumigatus, A. niger) are considered. According to several authors the prevalence of saprotrophic species of fungi that can produce mycotoxins and cause mycotoxicoses and opportunistic mycoses has now increased. In this regard constant monitoring of the phytosanitary situation in agricultural crops, careful mycological and mycotoxicological control of agricultural products, improvement of the species diagnosis of fungi are necessary.

Optimum Inhibition of Amphotericin-B-Resistant Candida albicans Strain in Single- and Mixed-Species Biofilms by Candida and Non-Candida Terpenoids

Candida albicans is one of the most common human fungal pathogens and represents the most important cause of opportunistic mycoses worldwide. Surgical devices including catheters are easily contaminated with C. albicans via its formation of drug-resistant biofilms. In this study, amphotericin-B-resistant C. albicans strains were isolated from surgical devices at an intensive care center. The objective of this study was to develop optimized effective inhibitory treatment of resistant C. albicans by terpenoids, known to be produced naturally as protective signals. Endogenously produced farnesol by C. albicans yeast and plant terpenoids, carvacrol, and cuminaldehyde were tested separately or in combination on amphotericin-B-resistant C. albicans in either single- or mixed-infections. The results showed that farnesol did not inhibit hyphae formation when associated with bacteria. Carvacrol and cuminaldehyde showed variable inhibitory effects on C. albicans yeast compared to hyphae formation. A combination of farnesol with carvacrol showed synergistic inhibitory activities not only on C. albicans yeast and hyphae, but also on biofilms formed from single- and mixed-species and at reduced doses. The combined terpenoids also showed biofilm-penetration capability. The aforementioned terpenoid combination will not only be useful in the treatment of different resistant Candida forms, but also in the safe prevention of biofilm formation.

Isolation of Cryptococcus species from the external environments of hospital and academic areas

Introduction: Fungi of the genus Cryptococcus are cosmopolitan and may be agents of opportunistic mycoses in immunocompromised and sometimes immunocompetent individuals. Cryptococcus species are frequently isolated from trees and bird excreta in the environment and infection occurs by inhalation of propagules dispersed in the air. The aim was to investigate Cryptococcus species in bird excreta and tree hollows located in a university hospital area and in an academic area of a university campus. Methodology: A total of 40 samples of bird excreta and 41 samples of tree hollows were collected. The identification of the isolates was done by classical methodology and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Results: Twenty (62.5%) isolates of Cryptococcus were found in bird excreta and 12 (37.5%) in tree hollows. C. laurentii (currently Papiliotrema laurentii) was the most frequent species in both samples, being found in 5 samples of excreta and in 8 tree hollows. The diversity of species found in excreta (C. laurentii, C. albidus [currently Naganishia albida], C. liquefaciens [currently N. liquefaciens], C. friedmanii [currently N. friedmannii] and others) was higher than in tree hollows (C. laurentii, C. flavescens [currently Papiliotrema flavescens], and other yeasts). Conclusion: Many Cryptococcus species were isolated from excreta and tree hollows, and this fact is important for understanding the environmental epidemiology of those emerging pathogens for public health, as a way to implement surveillance actions and control of cryptococcosis.

Opportunistic Fungal Infections in Small Animals

ABSTRACT Opportunistic fungal infections have long been recognized as rare causes of disease in immunocompetent dogs and cats. Recently, the escalating use of multiagent immunosuppression protocols (especially those that include cyclosporine) has resulted in an increased number of patients with opportunistic fungal infection encountered by small animal practitioners and has altered the typical case phenotype. Based on histologic and cytologic features such as pigmentation, hyphal diameter, and distribution in tissue, these opportunistic mycoses can be placed into categories such as phaeohyphomycosis, hyalohyphomycosis, and eumycotic mycetoma. This review aims to summarize the clinical presentations, methods for diagnosis, treatment recommendations, and prognosis for both immunocompetent and immunosuppressed patients with opportunistic fungal infections. An example case description is included to illustrate the most common current clinical presentation.