ABSTRACT
Following the COVID-19 infection, the sternum dislocation and wound dehiscence resulted in an infection complicating the recovery of an immunosuppressed patient after bilateral lung transplantation. Anaerobic culture (96 h) of milky cloudy wound secretion resulted in the growth of pinpoint haemolytic colonies identified as Metamycoplasma hominis (formerly Mycoplasma hominis). The search for the endogenous source of the infection found the bacterium exclusively in the patient's sputum, making a possible link to donor lung M. hominis colonization. Unfortunately, the donor samples were no longer available. The wound infection was successfully treated with 17 days of clindamycin despite the continuous PCR detection of M. hominis in the sputum after the end of the treatment.
Subject(s)
Lung Transplantation , Mycoplasma Infections , Mycoplasma hominis , Surgical Wound Infection , Humans , Lung Transplantation/adverse effects , Surgical Wound Infection/microbiology , Surgical Wound Infection/drug therapy , Surgical Wound Infection/diagnosis , Mycoplasma hominis/genetics , Mycoplasma hominis/isolation & purification , Mycoplasma Infections/microbiology , Mycoplasma Infections/diagnosis , Mycoplasma Infections/drug therapy , Male , COVID-19/diagnosis , Anti-Bacterial Agents/therapeutic use , Sputum/microbiology , Middle Aged , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Immunocompromised Host , Clindamycin/therapeutic useABSTRACT
Blood culture is the gold standard method for identifying the etiological agents of bloodstream infections. A relatively low sensitivity and a long time to detection are its main disadvantages, resulting in delayed administration of pathogen-specific antibiotic therapy and the need to initiate empiric treatment with broad-spectrum antibiotics. Such an approach negatively affects overall treatment outcomes and contributes to the spread of antibiotic resistance. Research in recent years has allowed the introduction of methods for rapid identification of pathogenic microbes from positive blood cultures, as well as methods for direct detection of bacteria and fungi from whole blood without the need for prior culture. Direct detection tests from whole blood have dramatically reduced the time to identify the causative pathogen of a bloodstream infection, but they also have their limitations. Methods that combine PCR and T2-weighted magnetic resonance imaging appear promising. This article provides an overview of diagnostic tests and a detailed description of the T2Bacteria Panel, its advantages and disadvantages based on prospective observational studies and review articles. Future implementation of these methods in the diagnosis of bloodstream infections and potentially localized infections could have a positive impact on the early administration of pathogen-specific antimicrobial therapy and subsequently on overall treatment outcomes, as well as on reducing the spread of antibiotic resistance.
Subject(s)
Bacteremia , Sepsis , Humans , Bacteremia/diagnosis , Bacteremia/drug therapy , Bacteremia/microbiology , Bacteria , Anti-Bacterial Agents/therapeutic use , Blood CultureABSTRACT
In the microbiological diagnosis of bloodstream infections (BSI), blood culture (BC) is considered the gold standard test despite its limitations such as low sensitivity and slow turnaround time. A new FDA-cleared and CE-marked platform utilizing magnetic resonance to detect amplified DNA of the six most common and/or problematic BSI pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli; referred to as ESKAPEc) is available and may shorten the time to diagnosis and potentially improve antimicrobial utilization. Whole blood samples from hospitalized patients with clinical signs of sepsis were analyzed using the T2Bacteria Panel (T2Biosystems) and compared to simultaneously collected BC. Discrepant results were evaluated based on clinical infection criteria, combining supporting culture results and the opinion of treating physicians. A total of 55 samples from 53 patients were evaluated. The sensitivity and specificity of the T2Bacteria panel was 94% (16 out of 17 detections of T2Bacteria-targeted organisms) and 100%, respectively, with 36.4% (8 of 22) causes of BSI detected only by this method. The T2Bacteria Panel detected pathogens on average 55 hours faster than standard BC. In our study, 9 of 15 patients with positive T2Bacteria Panel results received early-targeted antibiotic therapy and/or modification of antimicrobial treatment based on T2Bacteria Panel findings. Given the high reliability, faster time to detection, and easy workflow, the technique qualifies as a point-of-care testing approach.
