Conventional PCR as a reliable method for diagnosing invasive mucormycosis in resource-limited settings

2021 ◽  
Vol 70 (5) ◽  
Author(s):  
Mragnayani Pandey ◽  
Immaculata Xess ◽  
Gagandeep Singh ◽  
Rakesh Kumar ◽  
Manoranjan Mahapatra ◽  
...  

Introduction. Invasive mucormycosis (IM) is a life-threatening infection caused by fungi belonging to the order Mucorales. Histopathology, culture and radiology are the mainstay of diagnosis but lack sensitivity, leading to a delay in timely diagnosis and intervention. Recently, PCR-based approaches have been shown to be a promising method in diagnosing IM. Hypothesis/Gap Statement. Molecular-based approaches may be a valuable adjunct to standard conventional methods for diagnosing IM, especially among culture negatives and patients on antifungal therapy. Aim. In the present study we aimed to evaluate the clinical utility of panfungal and Mucorales-specific PCR for diagnosing IM from various clinical specimens. Methodology. This was a prospective study in which 239 clinically suspected cases of IM attending our tertiary care hospital from August 2015 to March 2018 were enrolled. All the cases were defined as ‘proven’, ‘probable’ or ‘possible’ based on EORTC/MSGERC guidelines. In addition to conventional diagnostics (KOH-calcofluor stain and culture), panfungal and Mucorales-specific PCR assays were also performed. The amplified products were sequenced for species identification. In vitro antifungal susceptibility was performed on all the culture-positive isolates. Results. Among 239 clinically suspected cases of IM, only 140 cases were diagnosed by the demonstration of aseptate ribbon-like hyphae on direct microscopy. Culture was positive in 35.7 % (54/140) of direct microscopy-positive samples. Among the proven cases (n=11), the sensitivity for both Mucorales-specific nested PCR and panfungal PCR was 100 %, but specificity was 91.9 and 73.7% respectively. In probable cases (n=129), the sensitivity of both the PCRs was 98.5 % and specificity for panfungal PCR was 73.7 and 91.9 % for Mucorales-specific PCR. Conclusion. Pan fungal PCR in combination with Mucorales-specific PCR, followed by sequencing, may play a significant role in IM diagnosis especially among those negative for both direct microscopy and culture.

Author(s):  
Vibha Mehta ◽  
Jagdish Chander ◽  
Neelam Gulati ◽  
Nidhi Singla ◽  
Hena Vasdeva ◽  
...  

Background and Purpose: Trichosporon species are ubiquitous in nature which are associated with fatal opportunistic invasive infections, especially in immunocompromised patients. The present study aimed to evaluate the epidemiological and clinical details, as well as the antifungal susceptibility pattern of the patients with Trichosporon infections. Materials and Methods: In total, 50 clinical isolates of Trichosporon species from various samples were included in this study. The samples were isolated over a period of 18 months from patients in a tertiary hospital in North India. The isolates were characterised phenotypically with Vitek MS (bioMérieux, France). Trichosporon spp. were isolated from urine (30%), nail (30%), tissue (16%), pleural fluid (14%), and sputum (5%). In total, majority of the isolates were of Trichosporon asahii (92%),followed by Trichosporon mucoides (6%), and Trichosporon ovoides (2%). It is noteworthy that most of the reported cases were from intensive care unit (34%). Results: Intravenous catheters, antibiotics, and antifungal uptake were significantly associated risk factors with Trichosporon infection. All invasive isolates were observed to be resistant in vitro to caspofungin and exhibited high minimum inhibitory concentration (MIC) values against amphotericin B, fluconazole, and 5-flucytosine. The MICs for voriconazole and posaconazole were low. Conclusion: Trichosporonosis is being increasingly reported all around the world,including India. The results of this study highlighted the importance of early detection and treatment for this emerging yeast and also added to the ongoing surveillance for the antifungal susuceptibility pattern for this fungus.


Author(s):  
Abirami Lakshmy Jayachandran ◽  
Radhika Katragadda ◽  
Ravinder Thyagarajan ◽  
Leela Vajravelu ◽  
Suganthi Manikesi ◽  
...  

Oropharyngeal candidiasis is one of the common manifestations seen in cancer patients on cytotoxic therapy and invasion into deeper tissues can occur if not treated promptly. Emergence of antifungal drug resistance is of serious concern owing to the associated morbidity and mortality. The present study aims at evaluation of clinicomycological association and antifungal drug susceptibility among the 180 recruited patients with cancer on chemotherapy and/or radiotherapy with signs or symptoms suggestive of oral candidiasis. Speciation and antifungal susceptibility was done by Microbroth dilution method for fluconazole, Itraconazole, and Amphotericin B as per standard microbiological techniques. Chi-square test was used for statistical analysis (p<0.05was considered statistically significant).Candida albicanswas the predominant species isolated (94) (58%) followed byCandida tropicalis(34) (20.9%). Fluconazole and Itraconazole showed an overall resistance rate of 14% and 14.8%, respectively. All the isolates were susceptible to Amphotericin B. There was a significant association between the presence of dry mouth and isolation ofCandida(p<0.001). Such clinicomicrobiological associations can help in associating certain symptoms with the isolation ofCandida. Species level identification with in vitro antifungal susceptibility pattern is essential to choose the appropriate drug and to predict the outcome of therapy.


2020 ◽  
Vol 13 (8) ◽  
Author(s):  
Hristina Yotova Hitkova ◽  
Diana Simeonova Georgieva ◽  
Preslava Mihailova Hristova ◽  
Teodora Vasileva Marinova-Bulgaranova ◽  
Biser Kirilov Borisov ◽  
...  

Background: Emerging non-albicans Candida (NAC) species are a major threat because of their intrinsic or acquired resistance to routinely applied antifungal agents. Objectives: The purpose of our study was to reveal in vitro activity of nine antifungal agents against NAC isolates. Methods: A total of 67 NAC (27 Candida glabrata, 10 C. tropicalis, 6 C. krusei, 6 C. parapsilosis, 4 C. lusitaniae, 4 C. lipolytica, etc.) were identified and tested. The antifungal susceptibility was estimated on the basis of minimum inhibitory concentrations (MIC). Results: Overall, 13 species were determined, of which C. glabrata was the most common (40.3%), followed by C. tropicalis (14.9%), C. krusei, and C. parapsilosis (8.9 % each). Forty-nine NAC isolates (73.13%) demonstrated decreased susceptibility to one or more antifungals, and 18 of them were resistant to all azoles. Out of 27 C. glabrata, 12 (44.4%) were resistant to fluconazole with MICs: 32 - >128 µg/mL and 15 (55.6%) were intermediate with MICs: 8 - 16 µg/mL Non-albicans Candida revealed a good susceptibility to echinocandins. Amphotericin B resistance was found in 5.97% of the isolates. Of particular interest was the detection of 6 (8.95%) multidrug-resistant NAC, which expressed resistance to azoles and echinocandins and/or amphotericin B. Conclusions: About one-fourth of the studied NAC were resistant to all azoles. These findings as well as the detection of several multidrug-resistant isolates determine the necessity of susceptibility testing of clinically important yeast isolates and control of the antifungal drugs in our hospital.


2017 ◽  
Vol 6 (05) ◽  
pp. 5379
Author(s):  
Vanathi Sabtharishi* ◽  
Radhika Katragadda ◽  
Thyagarajan Ravinder

Recent years, due to increased usage of antifungal treatment worldwide, there is an increased chance of rising resistance among antifungal drugs too. Dermatophytic infections causes’ superficial mycosis and it affects skin, hair and nail. These infections are more common and antifungal drugs are used everywhere to treat those common infections. To conduct a study by determining the antifungal susceptibility pattern in dermatophytic isolates from patients attending dermatology OPD in a tertiary care hospital. A total of 217 samples like hair, nail and skin scrapings were obtained and isolation of dermatophytes was done. Antifungal susceptibility testing for dermatophytes was performed by micro broth dilution method. Antifungal drugs tested were Griseofulvin, Fluconazole, Itraconazole and Ketoconazole. Minimum inhibitory concentration for each drug for fungal isolates was tested and results studied. Fluconazole showed a higher MIC values in the range of 1-8µg/ml. Itraconazole showed the lowest MIC values by micro broth dilution method. Since there is limitation of standard guidelines and protocol, meticulous research must be conducted on effect of antifungals and derive at universally implementable guidelines.


2020 ◽  
Vol 12 (03) ◽  
pp. 230-232
Author(s):  
Dhruv Mamtora ◽  
Sanjith Saseedharan ◽  
Ritika Rampal ◽  
Prashant Joshi ◽  
Pallavi Bhalekar ◽  
...  

Abstract Background Blood stream infections (BSIs) due to Gram-positive pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) are associated with high mortality ranging from 10 to 60%. The current anti-MRSA agents have limitations with regards to safety and tolerability profile which limits their prolonged usage. Levonadifloxacin and its oral prodrug alalevonadifloxacin, a novel benzoquinolizine antibiotic, have recently been approved for acute bacterial skin and skin structure infections including diabetic foot infections and concurrent bacteremia in India. Methods The present study assessed the potency of levonadifloxacin, a novel benzoquinolizine antibiotic, against Gram-positive blood stream clinical isolates (n = 31) collected from January to June 2019 at a tertiary care hospital in Mumbai, India. The susceptibility of isolates to antibacterial agents was defined following the Clinical and Laboratory Standard Institute interpretive criteria (M100 E29). Results High prevalence of MRSA (62.5%), quinolone-resistant Staphylococcus aureus (QRSA) (87.5%), and methicillin-resistant coagulase-negative staphylococci (MR-CoNS) (82.35%) were observed among bacteremic isolates. Levonadifloxacin demonstrated potent activity against MRSA, QRSA, and MR-CoNS strains with significantly lower minimum inhibitory concentration MIC50/90 values of 0.5/1 mg/L as compared with levofloxacin (8/32 mg/L) and moxifloxacin (2/8 mg/L). Conclusion Potent bactericidal activity coupled with low MICs support usage of levonadifloxacin for the management of BSIs caused by multidrug resistant Gram-positive bacteria.


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