Profile of co-infections & secondary infections in COVID-19 patients at a dedicated COVID-19 facility of a tertiary care Indian hospital: Implication on antimicrobial resistance

BACKGROUND

The COVID-19 pandemic has raised concerns over secondary infections because it has limited treatment options and empiric antimicrobial treatment poses serious risks of aggravating antimicrobial resistance (AMR). Studies have shown that COVID-19 patients are predisposed to develop secondary infections. This study was conducted to ascertain the prevalence and profiles of co- & secondary infections in patients at the COVID-19 facility in North India.

METHODS

We studied the profile of pathogens isolated from 290 clinical samples. Bacterial and fungal pathogens were identified, and antimicrobial susceptibility was determined by the Vitek2® system. Additionally, respiratory samples were tested for any viral/atypical bacterial co-infections and the presence of AMR genes by FilmArray test. The clinical and outcome data of these patients were also recorded for demographic and outcome measures analyses.

RESULTS

A total of 151 (13%) patients had secondary infections, and most got infected within the first 14 days of hospital admission. Patients aged >50 years developed severe symptoms (p = 0.0004) and/or had a fatal outcome (p = 0.0005). In-hospital mortality was 33%.K.pneumoniae (33.3%) was the predominant pathogen, followed by A. baumannii (27.1%). The overall resistance was up to 84%.Majority of the organisms were multidrug-resistant (MDR) harbouring MDR genes.

CONCLUSION

A high rate of secondary infections with resistant pathogens in COVID-19 patients highlights the importance of antimicrobial stewardship programs focussing on supporting the optimal selection of empiric treatment and rapid-de-escalation, based on culture reports.

Rapid chromatographic immunoassay-based evaluation of COVID-19: A cross-sectional, diagnostic test accuracy study & its implications for COVID-19 management in India

Background & objectives:

Coronavirus disease 2019 (COVID-19) has so far affected over 41 million people globally. The limited supply of real-time reverse transcription-polymerase chain reaction (rRT-PCR) kits and reagents has made meeting the rising demand for increased testing incompetent, worldwide. A highly sensitive and specific antigen-based rapid diagnostic test (RDT) is the need of the hour. The objective of this study was to evaluate the performance of a rapid chromatographic immunoassay-based test (index test) compared with a clinical reference standard (rRT-PCR).

Methods:

A cross-sectional, single-blinded study was conducted at a tertiary care teaching hospital in north India. Paired samples were taken for RDT and rRT-PCR (reference standard) from consecutive participants screened for COVID-19 to calculate the sensitivity and specificity of the RDT. Further subgroup analysis was done based on the duration of illness and cycle threshold values. Cohen's kappa coefficient was used to measure the level of agreement between the two tests.

Results:

Of the 330 participants, 77 were rRT-PCR positive for SARS-CoV-2. Sixty four of these patients also tested positive for SARS-CoV-2 by RDT. The overall sensitivity and specificity were 81.8 and 99.6 per cent, respectively. The sensitivity of RDT was higher (85.9%) in participants with a duration of illness ≤5 days.

Interpretation & conclusions:

With an excellent specificity and moderate sensitivity, this RDT may be used to rule in COVID-19 in patients with a duration of illness ≤5 days. Large-scale testing based on this RDT across the country would result in quick detection, isolation and treatment of COVID-19 patients.

Evaluation of COVID-19 Antigen Fluorescence Immunoassay Test for Rapid Detection of SARS-CoV-2

Introduction

Tests detecting SARS-CoV-2-specific antigen have recently been developed, and many of them are now commercially available. However, the real-world performance of these assays is uncertain; therefore, their validation is important. In this study, we have evaluated the performance of STANDARD F COVID-19 antigen fluorescence immunoassay (FIA) kit.

Methods

Nasopharyngeal samples collected from patients were subjected to the test as per manufacturer's instructions. The performance of the kit was compared with the gold standard real-time polymerase chain reaction.

Results

A total of 354 patients were tested with STANDARD F COVID-19 antigen FIA test kit. The overall sensitivity, specificity, positive predictive value, and negative predictive value of this test were found to be 38%, 99%, 96.2%, and 72%, respectively, with a diagnostic accuracy of 75.7%.

Conclusion

STANDARD F COVID-19 antigen FIA showed high specificity and positive predictive value but low sensitivity and negative predictive value.

Infection Trends, Susceptibility Pattern, and Treatment Options for Stenotrophomonas maltophilia Infections in Trauma Patients: A Retrospective Study

Introduction Stenotrophomonas maltophilia is an emerging environmental, gram-negative, multidrug-resistant organism, associated with risk factors such as prolonged hospitalization, invasive procedures, admission to the intensive care unit, mechanical ventilation, use of indwelling catheters, administration of immunosuppressants or corticosteroids, human immunodeficiency virus infection, underlying malignancy, and organ transplantation. The organism, despite being of low invasiveness in immune-competent individuals, is difficult to treat because of intrinsic resistance to several antimicrobial agents.

Materials and Methods This study focuses on commonly encountered resistance from among the isolates over a duration of 7 years from 2012 to 2018, analyzed retrospectively. Identification and susceptibility testing were performed using Vitek 2 (BioMérieux, Marcy-l'Etoile, France).

Results Bloodstream infections were found to be most common (52.02%), followed by respiratory infections (35.83%). The median age of the patients was 36 years, and male to female ratio was 143:27. The median duration of hospital stay was 18 days, and mortality was seen in 18.82% of patients. Susceptibility to cotrimoxazole and levofloxacin was seen in 97.1% of isolates (168 out of 173) and 90.1% of isolates (156 out of 173), respectively.

Conclusion Despite being effective in a majority of S. maltophilia isolates, both cotrimoxazole and levofloxacin have their shortcomings. Cotrimoxazole is bacteriostatic and can cause bone marrow suppression and resistance to levofloxacin sometimes develops during therapy. Thus, the therapy should be decided considering the characteristics of both of these drugs.

Utility of in-house and commercial PCR assay in diagnosis of Covid-19 associated mucormycoss in an emergency setting in a tertiary care center

Introduction. Invasive mucormycosis (IM) is a potentially fatal infection caused by fungi of the order Mucorales. Histopathology, culture, and radiology are the mainstays of diagnosis, but they are not sufficiently sensitive, resulting in delayed diagnosis and intervention. Recent studies have shown that PCR-based techniques can be a promising way to diagnose IM.Hypothesis/Gap Statement. Early diagnosis of fungal infections using molecular diagnostic techniques can improve patient outcomes, especially in invasive mucormycosis.Aim. The aim of this study was to evaluate the utility of our in-house mould-specific real time PCR assay (qPCR) in comparison with the commercially available real time PCR (MucorGenius PCR), for the early diagnosis of mucormycosis in tissue samples from patients with suspicion of invasive mucormycosis (IM). This in-house assay can detect and distinguish three clinically relevant mould species, e.g. Aspergillus spp., Mucorales and Fusarium spp. in a single reaction with only one pair of primers, without the need for sequencing.Methodology. We enrolled 313 tissue samples from 193 patients with suspected IM in this prospective study. All cases were classified using EORTC/MSGERC guidelines. All samples were tested using traditional methods, in-house qPCR, and MucorGenius PCR.Results. Using direct microscopy as a gold standard, the overall sensitivity and specificity of in-house qPCR for detection of IM was 92.46% and 80% respectively, while that of the MucorGenius PCR was 66.67% and 90% respectively. However, co-infection of IM and IA adversely affected the performance of MucorGenius PCR in detection of IM.The in-house PCR detected Aspergillus spp. in 14 cases and Fusarium spp. in 4 cases which showed clinical and radiological features of fungal sinusitis. The in-house qPCR also performed better in detecting possible cases of IM. This aids early diagnosis and appropriate treatment to improve patient outcomes.Conclusion. Because the in-house PCR is not only sensitive and specific, but also entirely based on SYBR Green for detection of targets, it is less expensive than probe-based assays and can be used on a regular basis for the diagnosis of IM in resource-constrained settings. It can be used to distinguish between mucormycosis and fungal sinusitis caused by Aspergillus and Fusarium in high-risk patients, as well as to accurately detect Mucorales in fungal co-infection cases.

Kodamaea ohmeri: A rare yeast causing invasive infections in immunocompromised patients

INTRODUCTION

Kodamaea ohmeri is a rare, recognized pathogen that has previously been isolated from environmental sources. The patients commonly affected by this yeast include immunocompromised as well as immunocompetent patients having several associated risk factors.

METHODOLOGY

We report three cases in which K. ohmeri was isolated from blood using Bact T/ALERT. Identification was carried out by MALDI-TOF MS (Vitek-MS, BioMérieux, Marcy-l'Etoile, France) in addition to color characteristics on chromogenic media. The patients had diminished immune response on account of a multitude of comorbidities.

RESULTS

K. ohmeri can be misidentified as Candida tropicalis, Candida albicans, or Candida hemolounii by conventional methods; correct and timely identification can be achieved by MALDI-TOF MS. Antifungal susceptibility breakpoints for K. ohmeri are currently not defined. An Echinocandin was added to the treatment regimen of all three of the cases.

CONCLUSIONS

Identification of K. ohmeri using conventional methods is difficult and unusual yeasts should be carefully observed, especially upon prolonged incubation.

P282 Bacterial co-infections in Mucormycosis infected COVID-19 patients: experience from a tertiary care center in India

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PM

During the second wave of COVID-19 in India, there was a deluge in Mucormycosis cases; which posed a serious threat as both conditions require extended hospital stay thus serving as an ideal setting for secondary infections.

Objectives

1. To ascertain the prevalence and anti-microbial profile of hospital-acquired secondary infections in COVID- 19 patients with Mucormycosis.

2. To evaluate the outcome in these patients and compare it with the outcome of COVID-19 patients with Mucormycosis but without any other secondary infection.

Methods

A 2-month retrospective observational study was conducted, where we compared outcomes in two groups of COVID-19 patients with Mucormycosis, one group being patients with secondary infections and the other group including patients without secondary infections.

A total of 180 samples from suspected cases of Mucormycosis, that underwent evaluation by conventional methods, KOH mount and cultures on SDA, were included. Fungal pathogens were identified from the positive cultures, based on macroscopic and microscopic features, as per standard Mycological methods.

Secondary infections inpatients were studied based on conventional bacteriological culture, microbiological profile, along-with identification and antibiotic susceptibility by VITEK 2. PCT and CRP values were also compared. The outcome was then evaluated. Data analysis was done using SPSS V-20.

Results

A total of 55 patients out of 140 patients, tested positive for Mucormycosis, either by KOH, culture or both. Rhizopus arrhizus was the most common isolate identified.

A total of 12/55 (21.8%) people with Mucormycosis developed secondary infections during their stay in the hospital, bloodstream infection being the most common (7/15; 46.67%). Overall, gram-negative (GN) organisms were more common (11/16; 68.75%), in comparison to Gram Positives (GP) (5/16; 31.25%), but the most common organism isolated was Enterococcus faecium (5/16; 31.25%), followed by Klebsiella pneumoniae (4/16) and E. coli (4/16). A total of 4/5 isolates (80%) of Enterococcus faecium were multi-drug resistant (MDR) and two of them were vancomycin-resistant. In all, 10/11 GN isolates (90.9%) were MDR, high resistance to carbapenems was observed, nine out of 11(81.81%) isolates were resistant to imipenem and eight (72.72%) were resistant to meropenem. A total of 3/12 (25%) patients succumbed to their infection in the group with secondary infections, after an average length of stay of 23.33 days. The most common cause of death in these patients was septic shock. A total of 8/43 (18.6%) succumbed to their infection in the group without any secondary infection at an average stay of 9.12 days in the hospital. CRP was found to be consistently elevated, this biomarker might not have a predictive value for bacterial infections in COVID-19 but PCT had a positive predictive value for the secondary bacterial infections overall (P-value <.001). Length of stay in hospital co-related with the development of secondary infection and mortality (P-value <.001).

Conclusion

Culture-based testing should be carried out before the administration of anti-microbials. PCT can be used as a guiding tool. Controlled use of antibiotics along with periodic surveillance and hand hygiene practices will immensely contribute to infection control.

Secondary Bacterial Infections in Mucormycosis-COVID-19 Cases: Experience during the Second COVID-19 Wave in India

In the second wave of COVID-19 in India, there was a new challenge in the form of mucormycosis. Coinfection with mucormycosis was perilous as both conditions required a prolonged hospital stay, thus serving as an ideal platform for secondary infections. Using a retrospective observational study, we studied secondary infections and their impact on the outcome in COVID-19 patients with mucormycosis. The outcome in these patients was evaluated and compared with COVID-19 patients with mucormycosis but without any secondary infection. SPSS V-20 was used for data analysis. Fifty-five patients tested positive for mucormycosis (55/140; 39.28). Twelve out of these 55 (21.8%) developed secondary infections during their hospital stay. Bloodstream infection was the most common (42.86%) secondary infection. The Gram-negative (GN) organisms were more common (11/16; 68.75%) compared with the Gram-positives (GP) (5/16; 31.25%). But the most common isolate was Enterococcus faecium (5/16; 31.25%). A high percentage of microorganisms isolated were multidrug-resistant (15/16; 93.75%). Two out of five (40%) isolates of Enterococcus faecium were vancomycin-resistant (VRE). High resistance to carbapenems was noted in the GN isolates (9/11; 81.81%). The comparison of length of stay in both subgroups was statistically significant (P value <0.001). When compared, the length of stay in people with adverse outcomes was also statistically significant (P value <0.001). Procalcitonin (PCT) had a positive predictive value for the development of secondary bacterial infections (P value <0.001). Antimicrobial stewardship and strict infection control practices are the need of the hour. IMPORTANCE Although our knowledge about COVID-19 and secondary infections in patients is increasing daily, little is known about the secondary infections in COVID-19-mucormycosis patients. Thus, we have intended to share our experience regarding this subgroup. The importance of this study is that it brings to light the type of secondary infections seen in COVID-19-mucormycosis patients. These secondary infections were partially responsible for the mortality and morbidity of the unfortunate ones. We, as health care workers, can learn the lesson and disseminate the knowledge so that in similar situations, health care workers, even in other parts of the world, know what to expect.

P385 Candida auris: a growing threat to global health

 

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PM

Background and Objectives

The emerging pathogen, C. auris, has been associated with nosocomial outbreaks in recent times. The true scale of the problem is difficult to comprehend due to several issues with the identification of C. auris using both phenotypic and molecular techniques. Most commonly, these isolates have been misidentified as C. haemulonii. Biofilm formation is strongly suggested given its association with intensive care settings, especially in patients with CVCs and long-term urinary catheters. Many isolates of C. auris have also shown raised MICs to multiple classes of antifungal agents, raising the possibility of pan-drug resistance.

Objective

To study the demographic characteristics, risk factors, and outcomes in patients with C. auris infection.

Methodology

This is a retrospective study from a tertiary care hospital (JPNATC, AIIMS) including all patients from the time period of 2018-2022 that showed growth of C. auris in any site. C. auris was identified using conventional methods (pale-pink growth on chromogenic medium, no pseudohyphae on germ-tube test, growth in presence of 10% NaCl) and VITEK-2. To reduce the misidentification and the intertest variability, the results were confirmed with MALDI-TOF. The risk factors and other patient information were taken from the HIS. Statistical analysis was performed.

Results

During the study period, a total of 31 patients had a C. auris infection. The most common age group was 20-40 years (n = 11,44%) with a preponderance in males (n = 23,74%). A total of 74% of the infections were found in blood, which was the most common site of infection followed by urine (10%). The other sites were pus-from-wound (n = 2), groin, nailbeds, and CVP tip (n = 1). Most of the cases were ICU patients (86%). All the patients with candidemia due to C. auris (n = 17 100%) had CVC, had surgery within the past 30 days, and were on broad-spectrum antibiotics and TPN. 71% (n = 12) had a history of immunosuppression and 18% (n = 14) had a history of prior antifungal therapy. Although 100% (n = 17) had the presence of an indwelling urinary catheter, none of them had candiduria due to C. auris. No patient with C. auris infection had neutropenia. The median LOS was 34.5 days. Most of the isolates were resistant to fluconazole (n = 13,93%), amphotericin B (n = 13,93%), voriconazole (n = 6,55%), flucytosine (n = 10,71%). A total of 87% (n = 12,87%) of isolates were sensitive to caspofungin and micafungin by VITEK-2 (limitation of this study). In all, 28% (n = 7) of the patients died whereas 40% (n = 10) were discharged. A total of 75% patients had clearing of the persistent candidemia when treated with caspofungin whereas only 25% patients had clearing of the candidemia when treated with voriconazole.

Conclusion

Most cases of C. auris infection were found in critical patients with the most common presentation being candidemia. The risk factors are similar to any other Candida infection. C.auris is the leading antimicrobial-resistant fungi and poses an additional burden to the healthcare system. The fungus has a high crude-mortality rate and we are running out of treatment options. A comprehensive intervention program with ongoing surveillance and good AMR practices is the need of the hour to reduce the burden of this dangerous pathogen.

E. hirae Causing Biliary Tract Infection in a Patient with Cholangiocarcinoma: A Case Report

INTRODUCTION

E. faecium and E. faecalis are the common species of Enterococcus responsible for the majority of infections. Earlier, species other than the common ones were usually unidentified and reported as Enterococcus species. However, modern equipment, like MALDI-TOF and VITEK2, have been utilitarian, helping us to identify the previously unidentified species. E. hirae is an organism seldom reported to cause human infections. Here, we report a case of a biliary tract infection in a female patient with cholangiocarcinoma caused by E. hirae.

CASE

A 56-year-old female presented with fever and abdominal pain. Bile aspirated during the ERCP was received in our laboratory. The gram stain of the bile sample revealed abundant polymorphonuclear leucocytes along with gram-positive diplococci. The organism failed to grow on MacConkey agar. On blood agar, non-hemolytic colonies grew. The organism was identified as E. hirae by MALDI-TOF MS. The antibiotic susceptibility performed using VITEK2 revealed it to be resistant to high-level gentamicin and susceptible to all remaining drugs. She was successfully treated with oral ciprofloxacin for the infection.

DISCUSSION

Bile is colonized with bacteria due to obstruction in the biliary tree, leading to cholangitis. This causes bacterial proliferation and translocation of bacteria into the systemic circulation. Our case was resistant to high-level gentamicin, while all previously reported cases were susceptible. The resistant isolates of E. hirae being isolated from cattle and their surroundings amidst the rampant use of antibiotics in livestock can pose a difficult situation for humans. Thus, there should be regulations on antibiotic usage in livestock. Cases like these should be reported and recognized for their potential to cause outbreaks if they remain unreported.

CONCLUSION

Thus, E. hirae, when encountered, should not be ignored but considered a pathogen and reported. The presence of drug-resistant organisms in cattle and their surroundings, their zoonotic potential to cause infections in humans, and the uncontrolled usage of antibiotics in livestock are causes for concern. Thus, we need to be more vigilant regarding it in the future.

Microbiological Profile and the Resistance Pattern of Pathogens in Neurosurgical Patients from a New Delhi Trauma Center

BACKGROUND

Neurosurgical patients are considered to be at higher risk for infections including nosocomial infections compared with other critically ill individuals. Empirical antimicrobial therapy is of utmost importance for the survival of infected neurosurgical patients.

METHODS

The microbial distribution and antimicrobial resistance patients from January 2012 to December 2021 (10 years) were analyzed retrospectively. Identification was done using VITEK-2 and MALDI-TOF systems. Antimicrobial susceptibility testing was determined by the Kirby Bauer Disk Diffusion Agar method (Clinical and Laboratory Standards Institute) and VITEK-2.

RESULTS

A total of 48,474 samples were received, out of which 10,134 (21%) had growth. Respiratory specimens showed the maximum isolation of pathogens (42% n = 4292). The predominant bacterial pathogens were gram negative (n = 8972; 88.5%), whereas gram positives were only 11.5% (n = 1162) of the total organisms. Among the gram positives, the most common was Staphylococcus aureus (64.6%), and among gram negatives, the most common pathogen was Acinetobacter baumanni (38.6%). The weighted average of the drug-resistance profile across all gram positives was >50% for fluoroquinolones (levofloxacin, ciprofloxacin), gentamicin, erythromycin, and ampicillin, and in the case of gram negatives it was >90% for ampicillin-sulbactam, ticarcillin, cefazolin, cefotaxime, and ceftriaxone. Thirty-two patients were found to have candidemia, out of which 6 were C. albicans and the rest were nonalbican. Six neurosurgery patients had infection with C. auris, 4 from blood samples and 2 from urine.

CONCLUSIONS

This study will add to the current knowledge and provide a better understanding of pathogen profile and resistance patterns in traumatic brain injury patients.

Utility of an in-house real-time PCR in whole blood samples as a minimally invasive method for early and accurate diagnosis of invasive mould infections

INTRODUCTION

Invasive mould infections (IMIs) are a leading cause of death in patients with compromised immune systems. Proven invasive mould infection requires detection of a fungus by histopathological analysis of a biopsied specimen, sterile culture, or fungal DNA amplification by PCR in tissue. However, the clinical performance of a PCR assay on blood samples taken from patients suspected of invasive mould disease has not been fully evaluated, particularly for the differential diagnosis of invasive aspergillosis (IA) and invasive Mucormycosis (IM).

OBJECTIVES

To assess the diagnostic utility of our previously validated in-house real-time PCR in blood samples for diagnosis of invasive aspergillosis and mucormycosis in patients with suspected invasive mould infection.

METHODS

All patients with suspected invasive mould infection were prospectively enrolled from May 2021 to July 2021. Conventional fungal diagnosis was performed using tissue and respiratory samples. In-house PCR was performed on blood samples and its diagnostic performance evaluated.

RESULTS

A total of 158 cases of suspected invasive mould infection were enrolled in the study. The sensitivity and specificity of in-house PCR performed on blood samples was found to be 92.5% and 81.4% respectively for diagnosis of probable IA, and 65% and 84.62% respectively for diagnosis of proven and probable IM. It was also able to detect 3 out of 5 cases of possible IM where no other microbiological evidence of IM was obtained.

CONCLUSIONS

This assay could be helpful in minimally invasive diagnosis of IMIs for patients in whom invasive sampling is not feasible, especially as a preliminary or screening test. It can help in early diagnosis, anticipating conventional laboratory confirmation by days or weeks. Possible correlation between fungal load and mortality can help in initiating aggressive treatment for patients with high initial fungal load.

P296 The role of Candida in acute pancreatitis: A disregarded pathogen

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PM

 

Background

Acute pancreatitis is often complicated by infection of peri-pancreatic necrotic tissue. The infectious etiology commonly involves gram negative enteric bacilli and enterococci. Role of Candida species has remained debatable, despite being isolated in pure or mixed cultures in specimens. We evaluated patients with acute pancreatitis with Candida infection over a duration of 4 years for assessment of risk and prognostic factors.

Objectives

To determine the prevalence and role of Candida infection in patients of acute pancreatitis and ascertain the species distribution and risk factors.

Methods

This study was conducted including adult patients who were admitted to gastro-surgery department and had clinical suspicion of peri-pancreatic fungal infection. Specimens included peri-pancreatic fluid collection obtained intra-operatively or aspirated USG-guided, drain fluid and blood. In addition to aerobic bacterial culture, fungal cultures were performed availing standard mycological procedures. Candida infections were categorized into true and possible as per Chakraborty et al. with some modifications.

True Candida infection of pancreatic tissue was considered when yeast cells were seen and grown in pure or mixed culture from

Possible Candida infection of pancreatic tissue was considered when Candida spp were isolated from

Relevant patient information was obtained from hospital information system. Data were analyzed by SPSS 20 statistical software and MS Excel.

Results

A total of 14 cases were identified amongst which 6/14 (42.9%) had true Candida infection whereas possible Candida infection was seen in 8/14 (57.1%) patients. Out of these, C. tropicalis was the predominant species seen in 9/14 (64.3%) whereas C. albicans was seen in 4/14 (28.6%). One isolate of C. auris was identified. Patients with C. tropicalis infection showed higher mortality (6/9, 66.7%) as compared with patients with other Candida species, in whom 20% (1/5) mortality was noted. Acknowledging limitations inherent to retrospective data extraction, we delineated some of the possible risk factors predisposing to Candida infection, given in Table 1.

Conclusion

Role of Candida species in the pathogenesis of adjacent tissues in case of acute pancreatitis has been neglected in past, but now being increasingly recognized. C. tropicalis is the commonest isolate in our study and carries very high mortality. Screening for Candida spp should be carried out in these patients in view of starting antifungal treatment at the earliest possible so that proper diagnosis and management can be undertaken.

High Prevalence of Fungal and NDM-OXA Producing Gram-Negative Bacterial Superinfections in the Second Wave of Coronavirus Disease 2019 in India: Experience from a Dedicated Coronavirus Disease 2019 Hospital in North India

Introduction

During the second wave of coronavirus disease 2019 (COVID-19), superinfection caused by fungus and multidrug-resistant bacteria worsened the severity of illness in COVID-19 patients. Limited studies from India reported the antimicrobial resistance pattern of secondary infections. In this study, we aim to study the epidemiology of pathogens causing superinfections and genotyping of Gram-negative isolates in COVID-19 patients.

Methods

This retrospective study was conducted at a dedicated COVID-19 center, India. The identification of bacteria/fungi was done by Vitek2^® and matrix-assisted laser desorption/ionization-time of flight mass spectrometry system. Identification of beta-lactamase genes was done using thermal cycler. The diagnosis of mucormycosis was based on 10% potassium hydroxide direct microscopy. Statistical analyses were performed using STATA version 15.1 (StataCorp., College Station, TX, USA). For continuous variables, mean and standard deviation were computed. For comparing proportions of secondary infections across admission location and outcomes, the Chi-squared test of independence was used. To compare the mean and median between intensive care units and outcomes, an independent t-test and a Mann-Whitney test were used.

Results

Of all the clinical samples, 45.4% of samples were cultured positive for secondary infections. Acinetobacter baumannii (35%) was the most common Gram-negative pathogen, while among Gram positive, it was Enterococcus faecium (40%). Among fungus, Candida spp. (61%) predominates followed by molds. Colistin and tigecycline proved effective against these pathogens. bla_NDM was the most prevalent gene followed by the bla_OX among the carbapenemase genes.

Conclusions

The mortality rate among COVID-19 patients with secondary infection was significantly higher compared to the overall mortality rate in COVID-19 patients.

P222 Epidemiology of Candida emia at level-1 trauma care cent er in North India

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PM

 

Objective

Patients affected by trauma who get admitted to critical care units experience prolonged hospitalization and thereby acquire several infections. This retrospective observational study was done from 2014 to 2021 to observe Candidaemia affecting this population. A total of 4816 patients admitted with traumatic injuries and hospitalized for treatment at ICU in our 190 bedded Level-1 Trauma center underwent this study.

Methods

Paired blood samples were collected from patients showing signs of sepsis and incubated and monitored regularly by the BacT/ALERT system (bioMe´rieux InC., Marcy l'Etoile, France). All the positive signal samples exhibiting budding yeast cells on Gram stain were subcultured on Chrome agar and Sabouraud dextrose agar. Pure growths obtained were subjected for identification and susceptibility by MALDI-TOF and VITEK 2 system.

Results

Out of the 4816 patients, 61 were affected by Candidaemia. Out of 61, the maximum was in the age group of 31-40 years (19.7%). Male preponderance (50/61, 82%) was exhibited compared to females. To ascertain Candidaemia, samples collected were blood (63/66, 95.5%) and CVP tip (3/66, 4.5%). Candidaemia was primarily observed in patients who suffered major orthopedic trauma (14/61, 21.2%). A total of 66 Candida species were isolated from samples of these patients. Out of these, Candida tropicalis (43.9%) was the most common, followed by C. parapsilosis (22.7%), C. albicans (21.2%), C. haemulonii (4.5%), C. glabrata (3%), C. rugosa (3%), and C. guilliermondii (1.5%). Concerning antifungal resistance, fluconazole resistance was 16.6% (11), flucytosine 1.5% (1), amphotericin B 6% (4), and micafungin 3% (2). Voriconazole was resistant to none but intermediate to 12.1% (8), caspofungin was intermediate to 3% (2), and resistant to none. A total of 47% (31/61) of patients succumbed to their injuries which were observed highest in the age group of 61-70 years (8/61, 25.8%). The most common injuries that the deceased suffered were polytrauma (9/61, 29%) and blunt trauma abdomen (9/61, 29%). Maximum mortality was also observed in patients with Candidaemia due to Candida tropicalis (15/61, 48.3%).

Conclusion

Candidaemia is usually fatal. Mortality due to Candidaemia increases in patients with severe traumatic injuries and added risk factors such as extremes of age, immunocompromised state, and broad-spectrum antibiotics. When compared to a similar study done in our center from 2009 to 2012 (3 years) on Candidaemia in ICU patients, the incidence was lower in our study (12.6% per 1000 ICU admissions vs 14.9% per 1000 ICU admissions), but the mortality rate was higher (47% vs 43.3%). Therefore, a watchful eye on early signs of sepsis, strict hospital infection control measures and antimicrobial stewardship may alter their outcome.

Utility of a multiplex pathogen detection system directly from respiratory specimens for treatment and diagnostic stewardship

The availability of syndrome-based panels for various ailments has widened the scope of diagnostics in many clinical settings. These panels can detect a multitude of pathogens responsible for a particular condition, which can lead to a timely diagnosis and better treatment outcomes. In contrast to traditional identification methods based on pathogen growth on culture, syndrome-based panels offer a quicker diagnosis, which can be especially beneficial in situations requiring urgent care, such as intensive care units. One such panel is the Biofire Filmarray Pneumonia plus Panel (BFP), which we have compared against microbiological culture and identification. The lower respiratory samples from patients were tested with BFP, culture, and identification with culture considered the gold standard. The phenotypic antibiotic susceptibility results (Vitek 2) were compared with the antimicrobial resistance (AMR) genes detected in BFP. Statistical analysis was carried out using GraphPad 7.0 and MS Excel (Microsoft Inc.). The results showed a positive percent agreement of 100% and a negative percent agreement of 47.8% with an overall agreement of 76.72% compared to culture. BFP was better at identifying fastidious bacteria, and the agreement with culture was higher for high bacterial identification numbers (107 and 106). There was also a correlation between the number of pathogens detected and growth in culture. Carbapenemase genes were detected in around 80% of phenotypically resistant samples and correlated with in-house PCR 60% of the time. Hence, BFP results need to be interpreted with caution especially when multiple pathogens are detected. Similarly, the presence or absence of AMR genes should be used to guide the therapy while being watchful of unusual resistance or susceptibility. The cost constraints and low throughput call for patient selection criteria and prioritization in emergency or resource-limited conditions.IMPORTANCEApplication of syndrome-based panels in clinical microbiology is of huge support in infectious conditions requiring urgent interventions, such as pneumonia. Interpreting the results requires caution; hence, we have compared the results obtained from Biofire Filmarray Pneumonia plus Panel with standard microbiological methods.

Therapeutic Drug Monitoring of Voriconazole in Children with Hematologic Malignancy and Invasive Fungal Infections: An RCT from a Tertiary Care Centre in India

INTRODUCTION

Voriconazole is a triazole anti-fungal with non-linear kinetics and a narrow therapeutic range. The objective of our study was to monitor the voriconazole serum levels in children with hematological malignancy and clinically suspected invasive fungal infections.

METHODS

The study was a prospective, randomized controlled trial conducted from June 2016 to December 2017. All children who had haematologic malignancies with clinically suspected invasive fungal infections and received voriconazole as the only anti-fungal were included in the study. The children were randomly allotted into two groups; one was the group that underwent TDM, and the other, TDM, was not done. Bioassay was the method employed for TDM. The trough levels were evaluated on a sample obtained on the fifth day of starting the drug. The institute's ethics committee approved the study.

RESULT

A total of 30 children were included in the study: 15 in the TDM group and 15 in the non-TDM group. The most common underlying malignancy was AML. Neutropenia due to chemotherapy sessions was these patients' most common risk factor. A favorable outcome was seen in 13/15 (86.7%) in the TDM group and 11/15 in the non-TDM group (73.3%).

CONCLUSION

Only five out of 15 (33.3%) children had voriconazole serum levels within the therapeutic range. Alterations in dose had to be done in the remaining to achieve the recommended serum levels. Thus, we recommend TDM for all children of hematologic malignancy receiving voriconazole for better management. Our findings also revealed that children with AML had lower than recommended levels of voriconazole on TDM evaluation, whereas those with ALL had normal to elevated levels of voriconazole.