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.
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.
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 outcomes of the disease are therapeutic challenges, leading to spirals of studies in search of 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 offtarget 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 the IL6-IL6R axis, using the available anti-IL6R mAb would be crucial. Moreover, 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.
is a dematiaceous fungus that belongs to the Coelomycetes class. While species within this class are known to cause human infection,
had previously only been known as phytopathogens and had never ...been isolated from a human sample.
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.
Here, we report the first case of human
infection in a patient with ovarian cancer.
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.
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.
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.
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.
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.
Non-
albicans Candida
species and other rare yeasts have emerged as major opportunistic pathogens in fungal infections. Identification of opportunistic yeasts in developing countries is mainly ...performed by phenotypic assay, which are time-consuming and prone to errors. The aim of the present study was to evaluate PCR-RFLP as a routinely used identification technique for the most clinically important
Candida
species in Iran and make a comparison with a novel multiplex PCR, called 21-plex PCR. One hundred and seventy-three yeast isolates from clinical sources were selected and identified with sequence analysis of the D1/D2 domains of rDNA (LSU rDNA) sequencing as the gold standard method. The results were compared with those obtained by PCR-RFLP using
MspI
restriction enzyme and the 21-plex PCR. PCR-RFLP correctly identified 93.4% of common pathogenic
Candida
species (
C. albicans
,
C. glabrata
,
C. parapsilosis
,
C. tropicalis
, and
P. kudriavsevii
(=
C. krusei
)) and was able to identify 45.5% of isolates of the uncommon yeast species compared to the D1/D2 rDNA sequencing. Compared with PCR-RFLP, all common
Candida
species and 72.7% of uncommon yeast species were correctly identified by the 21-plex PCR. The application of the 21-plex PCR assay as a non-sequence-based molecular method for the identification of common and rare yeasts can reduce turnaround time and costs for the identification of clinically important yeasts and can be applied in resource-limited settings.
Leptospirosis is a zooanthroponosis caused by the genus of
. It is an emerging public health problem due to its increasing incidence. The achievement to a vaccine that prevent from entrance of
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.
The genes encoding these proteins were cloned into pGH cloning vector and then
and
genes subcloned into pET-15b and pET-28a expression vectors, respectively. The hamsters were immunized with the purified recombinant proteins and challenged with
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
value < 0.05 statistically was considered significant.
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.
Based on our findings, rLcpA and rLenA proteins in combination with rLTB can protect the hamsters against
and effectively induce a protective antibody response. Thus, these proteins can be used as an additional prophylactic tool against leptospira.
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