COVID-19 associated mucormycosis (CAM) in Kashan, Iran: clinical presentations, risk factors, management, and outcomes

BACKGROUND

This study aimed to estimate the disease burden and describe the clinical presentation, risk factors, and outcome of CAM in a single centre in Iran.

METHODS

A case of mucormycosis was defined as one that had clinical and radiological features consistent with mucormycosis along with demonstration of the fungus in tissue via KOH mount/culture/histopathological and molecular examination.

RESULTS

We report 30 cases of COVID-19 associated mucormycosis (CAM). The results of this study showed the affected age group in the range of 40-79 years (median = 65.5; IQR = 5) with women (16/30, 53%) affected more than men (14/30, 47%). Among the fungi recovered, Rhizopus oryzae had the highest frequency (79%). Out of the 30 patients, 28 (93%) patients were diabetic with 24 (80%) patients having other co-morbidities. Headache followed by retro-orbital pain, proptosis/ptosis and rapid diminution of vision was a common sequence of symptoms reported by the majority of cases. Use of mechanical ventilation (58% vs. 6%, p = 0.003), O2 required (92% vs. 50%, p = 0.024), and development of renal dysfunction during hospital stay (17% vs. 0%, p = 0.041) was significantly higher in non-survivors than survivors. Temperature (C°), PR (pulse rate), mean levels of serum creatinine, BUN, troponin, and neutrophils were significantly higher in non-survivors (p < 0.05). Besides, Albumin and PO2 were also significantly higher in survivors than non-survivors.

CONCLUSION

Despite medical and surgical treatment, the mortality rate among CAM patients is still high. Thus, concerted efforts of revamping surveillance, diagnosis and management, along with public awareness and patient education, are the requisites for managing COVID-19 and mucormycosis.

P079 Virulence factors and azole-resistant mechanism of Candida tropicalis isolated from candidemia

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM

 

Background

Limited knowledge exists on the virulence factors of Candida tropicalis and the mechanisms of azole resistance that lead to an intensified pathogenicity and treatment failure. We aimed to evaluate the virulence factors and molecular mechanisms of azole resistance among C. tropicalis isolated from patients with candidemia.

Materials and Methods

Several virulence factors, including extracellular enzymatic activities, cell surface hydrophobicity (CSH), and biofilm formation were evaluated. Antifungal susceptibility pattern and expression level of ERG11, UPC2, MDR1, and CDR1 genes of 8 (4 fluconazole resistance and 4 fluconazole susceptible) clinical C. tropicalis isolates were assessed. The correlation between the virulence factors and antifungal susceptibility patterns was analyzed.

Results

During a 4-year study, 45 C. tropicalis isolates were recovered from candidemia patients. The isolates expressed different frequencies of virulence determinants as follows: coagulase 4 (8.9%), phospholipase 5 (11.1%), proteinase 31 (68.9%), esterase 43 (95.6%), hemolysin 44 (97.8%), biofilm formation 45 (100%), and CSH 45(100%). All the isolates were susceptible to amphotericin B and showed the highest resistance to voriconazole. There was a significant positive correlation between micafungin minimum inhibitory concentrations (MICs) and hemolysin production (rs = 0.316). However, we found a negative correlation between fluconazole MICs and esterase production (rs = −0.383). We observed the high expression of ERG11 and UPC2 genes in fluconazole-resistant C. tropicalis isolates.

Conclusion

Candida tropicalis isolated from candidemia patients extensively displayed capacities for biofilm formation, hemolysis, esterase activity, and hydrophobicity. In addition, the overexpression of ERG11 and UPC2 genes was considered one of the possible mechanisms of azole resistance.

Mass spectrometry in research laboratories and clinical diagnostic: a new era in medical mycology

Diagnosis by clinical mycology laboratory plays a critical role in patient care by providing definitive knowledge of the cause of infection and antimicrobial susceptibility data to physicians. Rapid diagnostic methods are likely to improve patient. Aggressive resuscitation bundles, adequate source control, and appropriate antibiotic therapy are cornerstones for success in the treatment of patients. Routine methods for identifying clinical specimen fungal pathogen are based on the cultivation on different media with the subsequent examination of its phenotypic characteristics comprising a combination of microscopic and colony morphologies. As some fungi cannot be readily identified using these methods, molecular diagnostic methods may be required. These methods are fast, but it can cost a lot. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is suitable for high-throughput and rapid diagnostics at low costs. It can be considered an alternative for conventional biochemical and molecular identification systems in a microbiological laboratory. The reliability and accuracy of this method have been scrutinized in many surveys and have been compared with several methods including sequencing and molecular methods. According to these findings, the reliability and accuracy of this method are very high and can be trusted. With all the benefits of this technique, the libraries of MALDI-TOF MS need to be strengthened to enhance its performance. This review provides an overview of the most recent research literature that has investigated the applications and usage of MT-MS to the identification of microorganisms, mycotoxins, antifungal susceptibility examination, and mycobiome research.

Changes in the expression of miR-103a and miR-21: a functional diagnosis of toxocariasis in rats

Introduction. Toxocariasis is a zoonotic parasitic disease caused by migrating nematode worms, Toxocara species larvae, within tissues. MicroRNAs (miRNAs) are small RNA molecules that regulate gene expression at a post-transcriptional level.Hypothesis/Gap Statement. miRNA-based diagnostic biomarkers for toxocariasis are emerging, but there is limited information about the role of many miRNAs and a more detailed diagnostic evaluation of miRNA expression patterns is needed to understand their immunobiological function.Aim. We investigated the expression levels of circulating miRNA 21 and miRNA 103a as potential biomarkers for the prediction and diagnosis of toxocariasis in Wistar rats infected with Toxocara canis.Methodology. Thirty Wistar rats were inoculated orally with 2500 T. canis embryonated eggs via gavage. Serum samples were collected from infected animals and were tested against T. canis antigens for 60 days post-infection. The plasma samples were isolated for quantitative real-time PCR (qPCR) assays and qPCR was used to assess transcription levels of miRNA 21 and miRNA 103a.Results. The prevalence of anti-Toxocara IgG was detected in 7/30 (23.3 %) infected rats. Molecular analysis of miRNAs 21 and 103a showed that expression levels of miRNAs in both groups of Toxocara-positive and negative samples were the same without significant association. The ratio of housekeeping gene expression (U6) to gene expression of miRNAs 21 and 103a indicated the rate of change (1/1.38 ≈ 0.75 and 1/0.751 ≈ 1.3, respectively).Conclusion. Our study revealed that miRNAs 21 and 103a might play fundamental roles as biomarkers and diagnostic tools for toxocariasis. However, the changes in expression of these miRNAs were not adequate to be used as biomarkers in diagnosis.

Clinical impact of Candida respiratory tract colonization and acute lung infections in critically ill patients with COVID-19 pneumonia

Coronavirus disease 2019 (COVID-19), which is attributable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been causing a worldwide health issue. Airways colonization by Candida spp. is prevalent among patients on automatic ventilation in intensive care units (ICUs). This research aimed to ascertain the risk factors and roles of Candida spp. respiratory tract colonization, and Candida lung infection during the progression of COVID-19 pneumonia in critically ill patients. In total, Candida spp. were recovered in 69 from 100 immunosuppressed patients with COVID-19. Bronchoscopy was used to collect the Bronchoalveolar lavage (BAL) specimens. For the identification of Candida spp. PCR sequencing was done using the ITS1 and ITS4 primers. The amplification of the HWP1 gene was conducted to identify the Candida albicans complex. The antifungal activities of fluconazole, itraconazole, voriconazole, amphotericin B and caspofungin against Candida spp. were evaluated using the Clinical and Laboratory Standards Institute M60. In 63.77% of the patients, Candida respiratory colonization at D0 and D14 had no impact on the severity of COVID-19. In comparison to C. albicans strains, Candida respiratory disorder with C. glabrata had influenced the severity of COVID-19 for critically ill patients following adjustment for the risk factors of COVID-19 (P < 0.05). Amphotericin B and caspofungin showed superior activity against all Candida spp. All antifungal agents showed 100% sensitivity against the two C. africana strains. Our observation on patients who used automatic ventilation, respiratory colonization by Candida spp. was not seen to influence the infection or death caused by COVID-19. Amphotericin B and caspofungin showed superior activity against all Candida spp. and were recommended for the treatment regime of pulmonary candidiasis associated with COVID-19 infection. Although “Candida pneumonia” is rarely being reported in critically ill patients, Candida airway colonization mainly by Candida albicans is common especially among patients with diabetes, malignancies, and kidney disorders.

Therapeutic strategies for COVID-19 patients: An update

The novel coronavirus SARS-coV-2, which emerged in Wuhan in November 2019, has increasingly spread causing a global pandemic that infected more than 444 million people, resulting in severe social and economic ramifications, and claimed more than 6,010,000 lives by March 5, 2022. The pandemic attracted global attention with consequential multiple economic, social, and clinical studies. Among causes of poor clinical outcome of the disease are therapeutic challenges, leading to spirals of studies in search for better therapeutic alternatives. Despite the worsening circumstances of the pandemic, no drug has yet shown remarkable efficacy in the clinical management of COVID-19 patients in large-scale trials. Many potential therapeutic strategies, including the use of nucleotide analogs, chloroquine phosphate, arbidol, protease inhibitors (lopinavir/ritonavir), plasma, monoclonal antibodies, plastic antibodies based on Molecularly Imprinted Polymers (MIPs), traditional Chinese medicine (TCM), nanomaterials, vaccine, and mesenchymal stem cells (MSCs), have emerged with various degrees of successes. Remdesivir and dexamethasone have now been licensed based on the results of randomized controlled trials. Baricitinib, the Janus kinase (JAK) 1/2 inhibitor, is also an attractive candidate due to its properties as a potent anti-inflammatory agent and its hypothesized off-target antiviral effects against SARS-CoV-2. Besides, human plasma from recovered COVID-19 patients is theoretically expected to be safe and effective for both therapy and post-exposure prophylaxis. In light of the literature, the correlation between the reduction of C5aR1/C5aR2 and IL6-IL6R axis, using the available anti-IL6R mAb would be crucial. More, MSCs are a potential therapeutic choice for patients with COVID-19 pneumonia. The coronavirus spike (S) protein that mediates the process of the infection via binding of host cells to the virus receptor is an essential focus for vaccine development. Importantly, with the number of patients increasing daily, there is an urgent need for effective therapeutic intervention. In this review, we expatiated on several strategies deployed for the treatment of COVID-19 infection.

The Epidemiological, Clinical, Mycological, and Pathological Features of Rhino-cerebral Mucormycosis: A Systematic Review

Cerebral mucormycosis (CM) is a life-threatening manifestation of mucormycosis, an angioinvasive fungal infection caused by Mucorales. We sought to systematically review all available case reports to describe epidemiologic features, clinical manifestations, predisposing factors, and diagnostic and treatment strategies of CM. A systematic search was conducted using a combination of the following keywords: "Mucor", "Zygomycetes", "mucormycosis", "cereb*", "brain", "central nervous system", and "intracranial", separately and in combination until December 31^st 2018. Data sources included PubMed, Scopus, EMBASE, Web of Science, Science Direct, and Proquest without limiting the time of publication. We included 287 articles corresponding to 345 cases of CM. Out of the 345 cases, 206 (60%) were male with a median age of 44 years; 130 (38%) were reported from North America; 87 (25%) from Asia; and 84 (24%) from Europe. The median time from onset of symptoms to presentation was 3-7 days (65/345, 65%). The highest mortality was observed among patients with diabetes mellitus (P=0.003). Debridement of infected brain tissue was associated with improved survival in CM cases (OR 1.5; 95% CI 01.3-1.8; P<0.0001). The use of liposomal amphotericin B (L-AMB) was significantly associated with patients' recovery (OR 2.09; 95% CI 1.2-3.4; P=0.003). The combination of L-AMB and posaconazole (12.5%) was more effective than the monotherapy treatment of CM cases (P=0.009). Clinicians should consider DM as an important risk factor for CM. Moreover, surgical debridement and antifungal combination therapy could be an effective approach in the management of CM patients.

Proven pulmonary aspergillosis in a COVID-19 patient: A case report

Background and Purpose:

Coronavirus disease 2019 (COVID-19) has become a significant clinical challenge in healthcare settings all over the world. Critically ill COVID-19 patients with acute respiratory distress syndrome may be at increased risk of co-infection with pulmonary aspergillosis. This study aimed to describe a clinical case of proven pulmonary aspergillosis caused by Aspergillus tubingensis in a 59-year-old man with a history of hospitalization due to COVID-19 infection.

Case report:

The Covid-19 infection was confirmed by positive nasopharyngeal polymerase chain reaction. He had a cavitary lesion measured 20 mm in diameter with intracavitary soft tissue density in the left lung in the first chest computerized tomography scan. After 25 days, he showed two cavitary lesions in both lungs which raised suspicion of fungal infection; hence, the patient underwent a trans-thoracic biopsy of the cavitary lesion. The direct examination and culture of the biopsy material revealed Aspergillus species. To confirm the Aspergillus species identification, the beta-tubulin region was sequenced. The patient was treated with oral voriconazole.

Conclusion:

This report underlined the importance of early diagnosis and management of invasive fungal infections in severe COVID-19 patients.

Molecular Characterization of Fungal Colonization on the Provox™ Tracheoesophageal Voice Prosthesis in Post Laryngec-tomy Patients

Background:

Tracheoesophageal voice prostheses (TVPs) have been the gold standard in rehabilitation, after laryngectomy, producing faster and premier voicing towards esophageal speech. Fungal colonization shortens the device’s lifetime and leads to prosthesis dysfunction, leakage, and subsequent respiratory infection. Therefore, in the current study, we aimed to investigate the fungal colonization patterns and to propose prophylactic measures that shall increase the longevity of voice prosthesis.

Methods:

Failed TVPs were removed - due to leakage and/or aspiration - from 66 post laryngectomy patients and examined. They were referred to Amiralam and Rasoul Hospital, the main centers of Ear, Nose, and Throat in Tehran, Iran from April 2018 to January 2020. Fungal colonization patterns were assessed using DNA sequencing techniques. Furthermore, the susceptibility to fluconazole, amphotericin B, nystatin, and white vinegar was evaluated according to the Clinical and Laboratory Standards Institute (CLSI) guidelines.

Results:

Resident fungal species from the upper airways colonized all the 66 TVPs (100%). Diabetes (31%) and smoking (98%) were the predominant underlying disease and predisposing factors, respectively. Among the 79 fungal agents isolated from the 66 TVPs, Candida glabrata (n=25, 31.7%) was the most common. A significant reduction in minimum inhibitory concentration (MIC) values were observed for white vinegar when used alone (P<0.05).

Conclusion:

White vinegar at a very low concentration could decrease the amount of fungal colonization on TVPs without any adverse effects; its wide accessibility and affordability ensure a decrease in the overall health cost.

Glucuronoxylomannan: the salient polysaccharide in cryptococcal immunity

<abstract> <p>Cryptococcal meningitis (CM) is a dominant cause of morbidity and mortality among patients with human immunodeficiency virus/ acquired immune deficiency syndrome (HIV/AIDS) caused by <italic>Cryptococcus neoformans</italic> and <italic>Cryptococcus gattii</italic> species complex. The complex is composed of closely related members, yet with diverse epidemiology, pathogenesis, and drug-resistant pattern. Cell-mediated immunity is the strongest pillar in immunity to cryptococcosis, further worsening HIV/AIDS patients' scenario. Antifungal resistance and immune evasion again tilt the host-parasite balance in favor of the fungal pathogen. In this regard, researchers are actively challenged to discover immunotherapy and vaccine for CM, to produce specific treatment and prevention that will address CM conventional therapeutics failure. As the major capsular polysaccharide of the <italic>Cryptococcus</italic>, which is tightly linked to pathogenicity, immunogenicity, and immune evasion, the glucuronoxylomannan (GXM) is cardinally targeted for vaccine and immunotherapy development. Further, the amount of GXM shed in body fluids correlates with the disease severity. Herein, we reviewed the literature with the journey so far in line with GXM as the salient immunological target on cryptococcosis.</p> </abstract>

Cross-sectional survey of knowledge and attitudes of healthcare workers and community members toward the Ebola virus disease and antimicrobial resistance pathogens outbreaks in Nigeria

Introduction

the 2014 Ebola virus disease (EVD) outbreak in Nigeria has further raised the awareness of health-care workers (HCWs) and community members (MCs) on the threat posed by infectious diseases and the need for improvement on infection control practices. However, awareness of dangers of increasing incidences of antimicrobial resistance (AMR) in hospitals and communities remained low.

Methods

a cross-sectional survey of awareness of 195 HCWs and 265 MCs toward EVD and AMR was conducted through a structured questionnaire.

Results

majority of HCWs (95.4%) and MCs (82.8%) still have knowledge of EVD´s danger and give reasons like its unique way of killing and unavailability of drugs for their awareness. Only 17.2% of MCs are aware of AMR as a problem, and only 3.4% of MCs and 10.3% of HCWs agreed that AMR is more dangerous than EVD. On the contrary, 76.4% of doctors, 95.1% nurses, 67.9% laboratory scientists, 66.7% pharmacists, 77.4% students and 100% of civil servants, drivers and religious leaders believed that EVD is more horrific and spread faster. They both attributed the rapid awareness of EVD in Nigeria, despite being new at the time of the outbreak, to the seriousness with which stakeholders and the media fought EVD, the gesture AMR is yet to receive. Though both HCWs and MCs agreed that prevention, not treatment is the best option to tackle Ebola like-diseases, but surprisingly, about 37% and 65% of HCWs and MCs respectively, still believe that traditional medicines can be used to treat Ebola related illnesses.

Conclusion

AMR awareness remains low among MCs and some HCWs when compared with EVD. It is recommended that efforts put in place during EVD outbreak by all stakeholders and the media need to be doubled to increase the knowledge of both HCWs and MCs toward AMR.

First molecular report of causative agent of otomycosis due to Aspergillus luchuensis

Otomycosis is a fungal infection of the external auditory canal caused mainly by the genus Aspergillus. Aspergillus luchuensis, an industrially important fungus, is a member of Aspergillus section Nigri. In this report, we present a case of otomycosis due to Aspergillus luchuensis in a 43-year-old female patient. We performed a partial PCR-sequencing of β-tubulin and calmodulin genes to identify the isolate to the species level. Further, we determined the in vitro susceptibility of the isolate to nystatin, clotrimazole and itraconazole according to the Clinical & Laboratory Standards Institute (CLSI) M38-A2 protocol. Accordingly, the minimum inhibitory concentrations of clotrimazole, nystatin and itraconazole were 0.25μg/mL, 0.5μg/mL and 1μg/mL, respectively. This is the first report of clinically relevant isolation of Aspergillus luchuensis identified by a molecular technique as a causative agent of otomycosis.

Virulence Factors and Azole-Resistant Mechanism of Candida Tropicalis Isolated from Candidemia

BACKGROUND

Limited knowledge exists on the virulence factors of Candida tropicalis and the mechanisms of azole resistance that lead to an intensified pathogenicity and treatment failure. We aimed to evaluate the virulence factors and molecular mechanisms of azole resistance among C. tropicalis isolated from patients with candidemia.

MATERIALS AND METHODS

Several virulence factors, including extracellular enzymatic activities, cell surface hydrophobicity (CSH), and biofilm formation, were evaluated. Antifungal susceptibility pattern and expression level of ERG11, UPC2, MDR1, and CDR1 genes of eight (4 fluconazole resistance and 4 fluconazole susceptible) clinical C. tropicalis isolates were assessed. The correlation between the virulence factors and antifungal susceptibility patterns was analyzed.

RESULTS

During a 4 year study, forty-five C. tropicalis isolates were recovered from candidemia patients. The isolates expressed different frequencies of virulence determinants as follows: coagulase 4 (8.9%), phospholipase 5 (11.1%), proteinase 31 (68.9%), esterase 43 (95.6%), hemolysin 44 (97.8%), biofilm formation 45 (100%) and CSH 45(100%). All the isolates were susceptible to amphotericin B and showed the highest resistance to voriconazole. There was a significant positive correlation between micafungin minimum inhibitory concentrations (MICs) and hemolysin production (r_s = 0.316). However, we found a negative correlation between fluconazole MICs and esterase production (r_s = -0.383). We observed the high expression of ERG11 and UPC2 genes in fluconazole-resistant C. tropicalis isolates.

CONCLUSION

C. tropicalis isolated from candidemia patients extensively displayed capacities for biofilm formation, hemolysis, esterase activity, and hydrophobicity. In addition, the overexpression of ERG11 and UPC2 genes was considered one of the possible mechanisms of azole resistance.

Molecular identification and clinical features of fungal rhinosinusitis: A 3-year experience with 108 patients

This study aimed to determine the prevalence, the causative agents, clinical features, and the risk factors associated with the fungal rhinosinusitis in a tertiary health center with a view to providing valid grounds that may guide healthcare professionals to effectively prevent, control, and treat fungal infections. All patients were subjected to diagnostic nasal endoscopy and CT scan of paranasal sinuses and FRS were confirmed by routine and complementary mycological and molecular methods. The inclusion criteria for invasive FRS were: confirmed diagnosis of IFRS according to the guidelines of the EORTC/MSG criteria (i.e., clinical, microbiological, and histological evidence of invasive fungal infection). From a total of 512 suspected patients, FRS was confirmed in 108 cases (21.1%). Our results showed FB (38/108; 35.2%) is the most common form of FRS followed by AIFRS (33/108; 30.6%), AFS (32/108; 29.6%), and CIFRS (5/108; 4.6%). A. flavus and Rhizopus oryzae were the most common causes of infection in AFS, FB, CIFRS, and AIFRS, respectively. Univariate analysis of variables predictive of AIFRS revealed 3 variables significantly associated with AIFRS. These included mucosal abnormalities of the middle turbinate and septum, and specifically, necrosis of the middle turbinate (P < .0001). Microbiological cultures, although useful for mycological speciation, are less sensitive. Furthermore, we used molecular methods to confirm the identity of some isolates that were not detectable using routine methods. Our data showed that the molecular methods and histologic diagnosis in all patients were more sensitive than the unenhanced sinus CT scan, and conventional microbiological methods.

First report of chronic invasive fungal rhinosinusitis in a patient with ovarian cancer caused by Didymella pedeiae and successful treatment with voriconazole: A case report

Background and Purpose:

Didymella pedeiae is a dematiaceous fungus that belongs to the Coelomycetes class. While species within this class are known to cause human infection,  D. pedeiae had previously only been known as phytopathogens and had never been isolated from a human sample.

Case report:

A 51-year-old Iranian female patient with ovarian cancer was admitted with unilateral lesions in paranasal sinuses and a five-month history of nasal obstruction, headache, postnasal drainage, swelling on the left side of the face, and orbital pain. Paranasal sinus computerized tomography scan revealed a soft tissue mass that filled the left nasal cavity, ethmoid, sphenoid, and frontal sinuses with more involvement in the maxillary and ethmoid sinuses. Antifungal treatment was simultaneously initiated with itraconazole+prednisolone 15 mg/day, and levofloxacin. Due to poor clinical response, IV voriconazole and amphotericin B were added to the treatment as well. The patient recovered completely after 10 weeks of therapy.

Conclusion:

Here, we report the first case of human D. pedeiae infection in a patient with ovarian cancer.

Determination of dermatophytes isolated from tinea capitis using conventional and ITS-based sequencing methods in Kano, Nigeria

BACKGROUND

Tinea capitis is a dermatophyte infection of the scalp and hair that affects a large number of people worldwide. The disease commonly affects children and manifests with varying degrees of hair loss, scalp inflammation, and psychosocial impact. In Nigeria, the burden of tinea capitis is worrisome affecting over 15,000,000 school-age children. Molecular techniques complement the conventional mycological examinations in laboratory diagnosis of tinea capitis. In this study, we identified dermatophytes species causing tinea capitis in Kano, Nigeria, using ITS-based nucleotide sequencing technique in addition to conventional mycological examination.

METHODS

We collected 112 samples from the scalp of children with clinically diagnosed tinea capitis at the dermatology clinic of Murtala Muhammad Specialist Hospital, Kano, between April and September 2019. The samples were processed and subjected to direct microscopy and mycological culture to isolate dermatophytes species that were identified morphologically and using ITS sequencing.

RESULTS

Out of the 112 patients investigated, the majority (59.8%) were between the ages 6 and 9 years with a mean age of 7.3 ± 1.9 years. Males (79.5%) were predominantly affected. Black dot (46.4%) was the most common clinical type of tinea capitis followed by gray patch (39.3%) and kerion (1.8%). Favus was not observed. Microsporum audouinii (45.7%) was the predominant etiologic agent followed by Trichophyton soudanense (28.6%), T. violaceum (22.9%), and T. tonsurans (2.9%).

CONCLUSION

The prominence of anthropophilic dermatophytes as the main causes of tinea capitis in our localities suggests that public health interventions to promote health education and good hygiene practices would minimize the transmission rate of tinea capitis among children in the study area.

The double-edged sword of systemic corticosteroid therapy in viral pneumonia: A case report and comparative review of influenza-associated mucormycosis versus COVID-19 associated mucormycosis

Acute respiratory distress syndrome is a common complication of severe viral pneumonia, such as influenza and COVID‐19, that requires critical care including ventilatory support, use of corticosteroids and other adjunctive therapies to arrest the attendant massive airways inflammation. Although recommended for the treatment of viral pneumonia, steroid therapy appears to be a double‐edged sword, predisposing patients to secondary bacterial and invasive fungal infections (IFIs) whereby impacting morbidity and mortality. Mucormycosis is a fungal emergency with a highly aggressive tendency for contiguous spread, associated with a poor prognosis if not promptly diagnosed and managed. Classically, uncontrolled diabetes mellitus (DM) and other immunosuppressive conditions including corticosteroid therapy are known risk factors for mucormycosis. Upon the background lung pathology, immune dysfunction and corticosteroid therapy, patients with severe viral pneumonia are likely to develop IFIs like aspergillosis and mucormycosis. Notably, the combination of steroid therapy and DM can augment immunosuppression and hyperglycaemia, increasing the risk of mucormycosis in a susceptible individual. Here, we report a case of sinonasal mucormycosis in a 44‐year‐old woman with hyperglycaemia secondary to poorly controlled diabetes following dexamethasone therapy on a background of influenza pneumonia and review 15 available literatures on reported cases of influenza and COVID‐19 associated mucormycosis.

Distribution of invasive fungal infections: Molecular epidemiology, etiology, clinical conditions, diagnosis and risk factors: A 3-year experience with 490 patients under intensive care

Recently, the prevalence of invasive fungal infections (IFIs) is rising. The global mortality rate of IFIs is 10-49%. This study aimed to determine the prevalence, the causative agents, and the risk factors associated with the invasive fungal infections in a tertiary health center to provide valid decision-grounds for healthcare professionals to effectively prevent, control, and treat fungal infections. The current study was conducted on 1477 patients suspected to have systemic fungal infections from different units of the hospital. After screening using routine mycological examination, the patients were confirmed with complementary mycological and molecular methods. Patients were included based on the confirmed diagnosis of IFI and excluded based on lack of a microbiologically and histologically proven diagnosis of IFI. Of the 1477 patients recruited in this study, confirmed cases of fungal infection were 490 (169 proven; 321 cases probable). Among the fungi recovered, Candida species had the highest frequency 337 (68.8%) followed by Aspergillus species 108 (22.1%), Zygomycetes species 21 (4.3%), non-Candida yeast 9 (1.8%). Others were black fungi 5 (1%), mycetoma agents 5 (1%), Fusarium 4 (0.8%), and Trichoderma (0.2%). Hematologic malignancies and diabetes mellitus were the most common underlying diseases among IFI-confirmed patients. This study observed an increased frequency of invasive candidiasis with non-albicans Candida and other invasive saprophytic fungal infections. The increased rate of invasive candidiasis with non-albicans agents highlights a new perspective in the epidemiology and treatment of invasive fungal infections.

Candida africana and Candida dubliniensis as causes of pediatric candiduria: A study using HWP1 gene size polymorphism

Background

Candida species cause a wide spectrum of disease entities. Candida africana and Candida dubliniensis-members of Candida albicans complex-are currently gaining both clinical and epidemiologic significance.

Materials and methods

Totally, 150 pediatric isolates that had previously been identified as C. albicans species complex based on a positive germ tube test were included. The isolates were cultured on CHROMagar Candida medium to ensure their purity and the results of germ tube test. For definitive speciation, PCR amplification and size polymorphism of the hyphal wall protein 1 (HWP1) gene was used. The results of HWP1-PCR were confirmed by sequencing the amplified fragments for randomly selected isolates of C. africana and C. dubliniensis.

Results

All 150 isolates included in this study were reconfirmed as C. albicans complex on chromogenic media. Based on the HWP1 gene size polymorphism, 141 (94%) isolates were identified as C. albicans, 2 (1.33%) as C. africana, and 1 (0.67%) as C. dubliniensis. The remaining 6 (4%) C. albicans complex isolates were a mix of C. albicans and C. africana. All isolates of C. africana and C. dubliniensis have been recovered from cases of candiduria.

Conclusion

C. africana, either alone or mixed with C. albicans, could be a cause of candiduria among pediatric patients and should not be ignored.

Molecular Cloning and Immunogenicity Evaluation of PpiC, GelE, and VS87_01105 Proteins of Enterococcus faecalis as Vaccine Candidates

Background

Among the enterococci strains, Enterococcus faecalis is considered as one of the important nosocomial pathogens affecting immunocompromised patients. In this study, the immunogenicity of PpiC, GelE, and VS87_01105 proteins against enterococcal infection was investigated in a mice model.

Methods

The genes encoding these proteins were cloned into pET21a expression vector, and the recombinant proteins were produced. Mice and rabbits were immunized with the purified recombinant proteins, and subsequently, mice were challenged with E. faecalis for the evaluation of their survival and bacterial clearances. The antibody responses to recombinant proteins were determined by ELISA assay, and opsonophagocytic activities of the antibodies were also measured. Passive immunization was performed using purified antibodies. Mice were challenged, and their survival and bacterial clearance were determined.

Results

Immunized mice with PpiC, GelE, and VS87_01105 recombinant proteins showed 80%, 70%, and 40% survival rate, respectively. The survival rates among passively immunized mice that received 500 µg of IgG fraction in 100 µl PBS buffer of each of anti-PpiC, anti-GelE, and anti-VS87_01105 were 60%, 50%, and 20%, respectively. The rates of opsonization with anti-PpiC, anti-GelE, and anti-VS87_01105 antibodies at 1/10 dilution were 77%, 64%, and 23%, respectively.

Conclusion

Based on our findings, PpiC, and GelE proteins can protect the mice against E. faecalis ATCC 29212 and effectively induce a protective antibody response. Thus, these proteins could be used as an additional therapeutic tool against enterococcal infections. Further studies to determine the role of PpiC in ligand binding and demonstration of epitope mapping may establish a credible target for vaccination.

Vaccine potential of LenA and LcpA proteins of Leptospira interrogans in combination with Escherichia coli heat-labile enterotoxin, B subunit (LTB)

BACKGROUND AND OBJECTIVES

Leptospirosis is a zooanthroponosis caused by the genus of Leptospira. It is an emerging public health problem due to its increasing incidence. The achievement to a vaccine that prevent from entrance of Leptospira interrogans to the deeper tissues of the host is needed. This study aimed to investigate the immunogenicity of LcpA (rLcpA) and LenA (rLenA) recombinant proteins in combination with LTB (rLTB) recombinant protein as an adjuvant against leptospiral infection in hamsters.

MATERIALS AND METHODS

The genes encoding these proteins were cloned into pGH cloning vector and then lenA, lcpA and ltb genes subcloned into pET-15b and pET-28a expression vectors, respectively. The hamsters were immunized with the purified recombinant proteins and challenged with Leptospira interrogans for evaluation of their survival. The antibody responses to the recombinant proteins were determined by ELISA. Then, data entered into SPSS software. Statistical Kruskal-Wallis test was used to compare the significant differences among different groups. The groups with significant differences were further analyzed by post hoc tests. The p value < 0.05 statistically was considered significant.

RESULTS

Immunized hamsters with rLenA-plus-rLTB, rLcpA-plus-rLTB and rLenA-plus-rLcpA-plus-rLTB proteins showed 60%, 74%, and 80% survival rates, respectively. A significant amount of interleukin-17 (IL-17), interleukin-4 (IL-4) and gamma interferon (IFNγ) cytokines were produced in immunized hamsters.

CONCLUSION

Based on our findings, rLcpA and rLenA proteins in combination with rLTB can protect the hamsters against L. interrogans and effectively induce a protective antibody response. Thus, these proteins can be used as an additional prophylactic tool against leptospira.

Prevalence of virulence genes and their association with biofilm formation in VRE faecium isolates from Ahvaz, Iran

INTRODUCTION

Vancomycin-resistant Enterococcus faecium (VREfm) is a common cause of nosocomial infections. Biofilm formation is an important factor in recurrence of infections, facilitating transfer of genetic elements, leading to treatment failures. The aim of this study was to investigate the virulence genes in biofilm producing isolates and to determine possible association between biofilm formation and the presence of these genes; also to determine association between antibiotic susceptibility patterns of VREfm isolates and their biofilm formation ability.

METHODOLOGY

A total of 57 isolates of VREfm were recovered from different sources of hospitals under Ahvaz University, Iran. The isolates were examined by conventional microbiological methods and molecular test using PCR. The antibiotic susceptibility patterns of the isolates were determined by disk-diffusion and E-test. The biofilm formation ability of the isolates was investigated by Modified Congo red agar and microtiter plate techniques. The presence of virulence genes was examined using Multiplex-PCR method.

RESULTS

Out of 57 VREfm isolates, 63.15% of isolates were biofilm producers. The frequency of biofilm producing isolates from clinical specimens, colonized patients and environmental sources were 78.26%, 60%, and 42.85%, respectively. The prevalence of acm, esp and hyl genes among biofilm producing isolates was 86.10%, 55.56% and 52.77%, respectively. There was statistically significant association between esp gene and biofilm formation among isolates from the clinical specimens.

CONCLUSION

Clinical isolates producing biofilms showed a positive association with the presence of the esp. Our study further suggests that the link between virulence genes and biofilms is affected by the environmental context.