The clinical and microbiological characteristics of infections in burn patients from the Formosa Fun Coast Dust Explosion

Review on infection control strategies to minimize outbreaks of the emerging pathogen Elizabethkingia anophelis

BACKGROUND

Elizabethkingia anophelis is a multi-drug resistant emerging opportunistic pathogen with a high mortality rate, causing healthcare-associated outbreaks worldwide.

METHODS

We report a case of E. anophelis pleuritis, resulting from transmission through lung transplantation, followed by a literature review of outbreak reports and strategies to minimize E. anophelis transmission in healthcare settings.

RESULTS

From 1990 to August 2022, 14 confirmed E. anophelis outbreak cohorts and 21 cohorts with suspected E. anophelis outbreaks were reported in literature. A total of 80 scientific reports with recommendations on diagnostics and infection control measures were included and summarized in our study.

CONCLUSION

Strategies to prevent and reduce spread of E. anophelis include water-free patient rooms, adequate hygiene and disinfection practices, and optimized diagnostic techniques for screening, identification and molecular typing.

Septic Shock After Kidney Transplant: A Rare Bloodstream Ralstonia mannitolilytica Infection

Background

Ralstonia mannitolilytica, an emerging opportunistic pathogen, can infect immunocompromised patients but is a rare cause of severe sepsis and septic shock in kidney transplant recipients (KTRs).

Case Presentation

We present a case of septic shock after renal transplant in a 41-year-old male, which was finally proven to be caused by Ralstonia mannitolilytica through blood cultures and mass spectrometric analysis following the negative result of metagenomic next-generation sequencing (mNGS). He was finally cured after the application of sensitive antibiotics (sulfamethoxazole-trimethoprim, amikacin and piperacillin-tazobactam) based on the drug sensitivity test results. The patient had a satisfactory recovery with no complications during a 6-month follow-up period.

Conclusion

This study highlights that Ralstonia mannitolilytica is an easily overlooked cause of septic shock in KTRs requiring a detailed inquiry of medical history with inflammatory markers monitored closely. Traditional blood cultures still should be taken seriously. It also provides a cautionary tale that negative results of mNGS have to be interpreted with caution.

Risk factors for nosocomial infections and/or sepsis in adult burns patients: An integrative review

BACKGROUND

In comparison to general trauma patients, loss of skin barrier amongst the burns cohort predisposes them to a higher risk of nosocomial infections and sepsis, and this often leads to unfavourable morbidity and mortality outcomes.

PURPOSE

This integrative review aimed to explore existing literature to identify risk factors related to nosocomial infections and/or sepsis in adult burns patients following hospital admission.

METHODS

Electronic searches for journals published between 2007 and 2021 were performed in CINAHL, Scopus and Medline, and key journals were hand-searched. Inclusion criteria was: (1) peer-reviewed, primary studies; (2) qualitative, quantitative or mixed-methods studies; (3) study participants had sustained burns-related injury and developed nosocomial infections and/or sepsis during the course of hospitalisation. Studies were appraised using the Critical Appraisal Skill Program checklists.

RESULTS

15 studies ranging from 'poor' to 'fair' to 'moderate' quality were included in the final review. Patient factors that contributed to the development of nosocomial infections and/ or sepsis included: (1) Full thickness burns; (2) age; (3) % Total Burns Surface Area; and (4) Herpes Simplex Virus activation. Several provider-system risk factors were identified by 'poor' quality studies and further research is required to substantiate those findings.

DISCUSSION

Findings remained inconclusive due to the lack of 'good' quality studies however, there was an overemphasis on patient-related risk factors instead of healthcare workers or the system. Future research may focus on activation of the latest infection prevention strategies and early enforcement of care bundles. Through identification of related risk factors, it may reduce the incidence of nosocomial infection and/or sepsis post-burns.

Antimicrobial Photodynamic Therapy Mediated by Fotenticine and Methylene Blue on Planktonic Growth, Biofilms, and Burn Infections of Acinetobacter baumannii

Antimicrobial photodynamic therapy (aPDT) is considered a promising alternative strategy to control Acinetobacter baumannii infections. In this study, we evaluated the action of aPDT mediated by a new photosensitizer derivative from chlorin e-6 (Fotoenticine—FTC) on A. baumannii, comparing its effects with methylene blue (MB). For this, aPDT was applied on A. baumannii in planktonic growth, biofilms, and burn infections in Galleria mellonella. The absorption of FTC and MB by bacterial cells was also evaluated using microscopic and spectrophotometric analysis. The results of planktonic cultures showed that aPDT reduced the number of viable cells compared to the non-treated group for the reference and multidrug-resistant A. baumannii strains. These reductions varied from 1.4 to 2 log10 CFU for FTC and from 2 log10 CFU to total inhibition for MB. In biofilms, aPDT with MB reduced 3.9 log10 CFU of A. baumannii, whereas FTC had no effect on the cell counts. In G. mellonella, only MB-mediated aPDT had antimicrobial activity on burn injuries, increasing the larvae survival by 35%. Both photosensitizers were internalized by bacterial cells, but MB showed a higher absorption compared to FTC. In conclusion, MB had greater efficacy than FTC as a photosensitizer in aPDT against A. baumannii.

Oxacillinases and antimicrobial susceptibility of Ralstonia pickettii from pharmaceutical water systems in Croatia

This study evaluated antibiotic susceptibility and presence of bla_OXA22 and bla_OXA60 genes in 81 isolates of Ralstonia pickettii obtained from different purified and ultra-pure water systems in two different geographical areas of Croatia. E-test and disk diffusion test were performed to determine antibiotic susceptibility. Polymerase Chain Reaction was applied to detect genes encoding OXA-22 and OXA-60, oxacillinases previously identified in R. pickettii. The isolates were genotyped by pulsed-field gel electrophoresis. The results revealed variable susceptibility/resistance profiles. Our isolates exhibited high susceptibility rates to ceftriaxone, cefotaxime, piperacillin-tazobactam, ciprofloxacin, imipenem, cefepime and in lesser extent to ceftazidime. High rates of susceptibility were also observed for sulfamethoxazole-trimethoprim and piperacillin. High resistance rates were noticed for ticarcillin-clavulanate, aztreonam and meropenem, as well as for all aminoglycosides tested. Modified Hodge test was positive in 51,9% strains, indicating production of carbapenemases. bla_OXA22 and bla_OXA60 genes were detected in 37.0% and 80.3% strains, respectively. Pulsed-field gel electrophoresis identified three major clusters containing subclusters. R. pickettii should be taken seriously as a possible cause of nosocomial infections to ensure adequate therapy, to prevent the development of resistant strains and to try to reduce the possibility of R. pickettii surviving in clean and ultra clean water systems.

Application of mNGS to describe the clinical and microbial characteristics of severe burn a tanker explosion at a tertiary medical center: a retrospective study patients following

Background

Multiple organ dysfunction syndrome secondary to infection is the leading cause of death in burn patients. Bloodstream infection (BSI) and the prognosis of burn patients are negatively correlated. Metagenomic next-generation sequencing (mNGS) can detect many potential pathogens and may be more valuable for patients with severe burns.

Methods

We retrospectively explored the utility of mNGS in describing the clinical and microbial characteristics of severely burned patients with BSI. We compared mNGS with blood culture.

Results

Fourteen patients (127 blood samples) developed 71 episodes of BSIs with 102 unique causative pathogens. The median total body surface area was 93%. The overall 90-day mortality was 43%. In total, 17 (23.9%) episodes were polymicrobial, and 61 (86.1%) episodes originated from the wound. In total, 62/71 cases (87%) showed positive findings by mNGS, while 42/71 cases (59%) showed positive findings using blood culture. We found that mNGS outperformed culture, especially in terms of fungi (27% vs. 6%, p < 0.0001).

Conclusions

The incidence of BSI and polymicrobial in patients with large-area severe burns is high. mNGS has potential value in the diagnosis of fungal infections and coinfections in such patients. In addition, mNGS may provide unique guidance for antibiotic therapy in complicated BSI.

Does early bloodstream infection pose a significant risk of in-hospital mortality in adults with burns?

BACKGROUD/PURPOSE

Bloodstream infections (BSI) are common in patients with major burns, but its effect on mortality remains controversial. This study was aimed to investigate if BSI is significant risk factor of mortality?

METHODS

This is a retrospective chart review study included 266 adult patients admitted to our burn center from 2000 to 2019. Age, sex, inhalation injuries, total burn surface area (TBSA), duration of stay in intensive care unit, BSI and mortality were variables studied. Fisher exact test, Mann-Whitney test and logistic regression was used for statistical analysis.

RESULTS

There were 234 survivors and 32 non-survivors. Male was predominant. The overall incidence of BSI was 18.8%, and the overall crude mortality was 12%. Burns ≥30% TBSA and BSI were significant risk factors. A predictive function based on30% TBSA and BSI within 14 days after the onset of burns (BSI-14) was derived. The function has a sensitivity of 0.97, specificity of 0.42 and achieved a maximum Youden Index at functional value ≥0.05727. The mortality probability of BSI-14 in burns ≥30% TBSA was 40.8%.

CONCLUSIONS

BSI and burns ≥30% TBSA were significant risk factors of mortality. Early detection of BSI-14 is critical in burn care as its probability of mortality can be as high as 40% in patients ≥30% TBSA of burns. To reduce the risk of mortality, early in ventilator withdrawal, invasive lines and tubes removal, and early grafting should be emphasized besides infection control and appropriate use of antibiotics.

Initial white blood cell count and revised Baux score predict subsequent bloodstream infection in burn patients: A retrospective analysis of severe burn patients from the Formosa color dust explosion of 2015

BACKGROUND

Infections are the most common complications among hospitalized severe burn patients. However, limited literature reports early effective predictors of bloodstream infections (BSI) among burn patients. This study aimed to identify cost-effective biomarkers and valuable clinical scoring systems in the emergency department (ED) for the prediction of subsequent BSI in mass burn casualties.

METHODS

In 2015, a flammable cornstarch-based powder explosion resulted in 499 burn casualties in Taiwan. A total of 35 patients were admitted at Taipei Veterans General Hospital. These severe burn patients (median total body surface area [TBSA] 54%) were young and previously healthy. We assessed the potential of various parameters to predict subsequent BSI, including initial laboratory tests performed at the ED, TBSA, and multiple scoring systems.

RESULTS

Fourteen patients (40.0%) had subsequent BSI. The most common causative pathogen was the Acinetobacter baumannii (Ab) group, mostly carbapenem resistant and associated with a poor outcome. The area under the receiver operating characteristic curve revealed that the revised Baux score, TBSA, and initial white blood cell count had excellent discrimination ability in predicting subsequent BSI (0.898, 0.889, and 0.821, respectively). The rate of subsequent BSI differed significantly at the cut-off points of revised Baux score >76, TBSA >55%, and WBC count >16,200/mm³.

CONCLUSION

The initial WBC count at the ED, TBSA, and revised Baux score were good and cost-effective biomarkers for predicting subsequent BSI after burn injuries.

Difficult to Treat Infections in the Burn Patient

Background: Unusual infections can lead to complications in more severely burned patients and pose major challenges in treatment. Methods: The published literature of retrospective reviews and case series of the uncommon infections of osteomyelitis, polymicrobial bacteremia, recurrent bacteremia, endocarditis, central nervous system (CNS), and rare fungal infections in burned patients have been summarized and presented. Results: When compared with infections occurring in the non-burn population, these infections in burn patients are more likely to be because of gram-negative bacteria or fungi. Because of hyperdynamic physiology and changes in immunomodulatory response secondary to burns, the clinical presentation of these infections in a patient with major burns differs from that of the non-burn patient and may not be identified until the post-mortem examination. Some of these infections (osteomyelitis, endocarditis, CNS, rare fungal infections) may necessitate surgical intervention in addition to antimicrobial therapy to achieve cure. The presence of the burn and allograft can also present unique challenges for surgical management. Conclusions: These difficult and unusual infections in the severely burned patient necessitate an index of suspicion, appropriate diagnosis, identification and sensitivities of the putative pathogen, effective systemic antimicrobial therapy, and appropriate surgical intervention if recovery is to be achieved.

Trends in microbial profile of burn patients following an event of dust explosion at a tertiary medical center

Background

Microbial infection is the main cause of increased morbidity and mortality in burn patients, especially infections caused by multiple drug-resistant organisms (MDRO). The purpose of this study was to explore major microbial trends in burn patients.

Methods

This retrospective study was conducted at burn wards and intensive care units, where burn patients were admitted following an event of dust explosion. Data were collected for a number of variables including severity of burns, demographic and clinical characteristics, laboratory data, and therapeutic devices.

Results

A total of 1132 specimens were collected from 37 hospitalized burn patients with mean TBSA of 46.1%.The most commonly isolated species were Staphylococcus spp. (22.4%). The highest rate of antibiotic resistance was observed in carbapenem–resistant A. baumannii (14.6%), followed by methicillin-resistant S. aureus (11.3%). For each additional 10% TBSA, the isolation of MDRO increased 2.58–17.57 times (p < 0.05); for each additional 10% of the third-degree burn severity, the risk of MDRO significantly decreased by 47% (95% CI, 0.38–0.73, p < 0.001) by Cox model.

Conclusions

The proportion of overall microbial isolates increased with the increase in TBSA and duration of time after burns. The extent of TBSA was the most important factor affecting MDRO.

Microbiology and clinical characteristics of industrial oil burns

INTRODUCTION

Infections complicating burns generally transition from Gram-positive to Gram-negatives over the first couple weeks, but this depends on multiple factors. The microbiology of infections complicating crude oil (CO) and hydraulic fracturing (FRAC) burns is unknown.

METHODS

We performed a retrospective study of patients with industrial thermal burns hospitalized >2 days with ≥1 day in the ICU between 4/2011-11/2016. Burns were oil-related (ORB; CO or FRAC) or non-oil related (NORB). Epidemiology and microbiology during the first 15 hospital days was compared.

RESULTS

149 patients were included, with 11 FRAC and 24 CO. CO burns were more severely burned than those with FRAC and NORB (p<0.05). Mortality was 17% and 18% for CO and FRAC burns compared to 3% in NORB (p<0.01). More cultures were obtained from ORB than NORB (p<0.05). ORB were associated with Stenotrophomonas maltophilia and FRAC associated with Serratia marcescens and Candida glabrata. Patients with FRAC, CO and NORB had a median of 13, 3.5, and 4 days to first positive culture respectively (p=0.03).

CONCLUSION

ORB were associated with more severe burns and unique microbiology. FRAC burns had longer to initial positive culture, potentially suggesting our current methodology is inadequate to diagnose infections associated with FRAC.

Lytic Bacteriophage Screening Strategies for Multidrug-Resistant Bloodstream Infections in a Burn Intensive Care Unit

BACKGROUND Increasing antibiotic resistance and multidrug resistance (MDR) in patients with bloodstream infection (BSI) has resulted in treatment using bacteriophage. This study aimed to identify Gram-negative bacilli and Gram-positive cocci and antibiotic resistance in patients with BSI in a burn intensive care unit (BICU). The environment, including sewage systems, were investigated for the presence of lytic bacteriophage. MATERIAL AND METHODS Between January 2011 to December 2017, 486 patients with BSI were admitted to the BICU. Blood culture identified the main infectious organisms. Bacterial screening tests for antibiotic resistance included the D test and the modified Hodge test (MHT). Lytic bacteriophage was isolated from the environment. RESULTS In 486 patients with BSI, the main causative organisms were Gram-negative bacilli (64.6%), Gram-positive cocci (27.7%), and fungi (7.7%). The main pathogenic organisms that showed multidrug resistance (MDR) were Acinetobacter baumannii (26.0%), Staphylococcus aureus (16.8%), and Pseudomonas aeruginosa (14.2%). Bacteriophage was mainly isolated from Gram-negative bacilli. Screening of hospital and residential sewage systems identified increased levels of bacteriophage in hospital sewage. CONCLUSIONS The causative organisms of BSI and the presence of MDR in a hospital BICU were not typical, which supports the need for routine bacterial monitoring. Hospital sewage provides a potential source of bacteriophage for the treatment of MDR pathogenic bacteria.