Clinical Microbiology Newsletter最新文献

The blood brain barrier (BBB) controls the passage of molecules between the circulatory system and the central nervous system. Despite this, some fungi find ways to bypass the BBB, resulting in infections of the central nervous system (CNS) including meningitis, meningoencephalitis, and abscesses. While these infections are rare, the resultant mortality rates range from 30 to 99%, in part due to the poor penetration of most commercially available antifungals. Additionally, laboratory diagnostics can lack sensitivity and/or specificity and may require specialized diagnostic testing facilities, also contributing to the high mortality rate seen in CNS mycoses. Despite the high risk of mortality, detailed understanding of how these infections occur is limited to only a few of the most common fungi, and there is a dearth of research examining novel therapies to aid in the treatment of these infections.

Cytomegalovirus (CMV) is the most common congenital infection worldwide. Twenty percent of congenital CMV (cCMV) infections result in permanent disability, including hearing loss, cognitive deficits, cerebral palsy, and vision impairment, and 4% of cases result in death. Early recognition and diagnosis are imperative, as both antiviral treatment and non-pharmaceutical interventions can improve patient outcomes by reducing hearing loss, other symptomology, and overall disease severity. Specifically, evidence of effective therapy for symptomatic infants and, more recently, reduced fetal transmission following treatment of maternal primary infection may support expanded screening activities. Here, we present an overview of the clinical presentation, treatment and prevention of maternal CMV and cCMV infection. We discuss in detail new diagnostic methods for early and retrospective detection of congenital and maternal primary infections. Finally, we review proposed neonatal and prenatal screening strategies. Clinical laboratories should be aware of the latest clinical studies, the changing diagnostic landscape, and laboratory practices for cCMV and maternal CMV infection.

Tetracycline class antibiotics have activity against a wide range of Gram-positive, Gram-negative, and atypical bacterial pathogens, and they have been used for treatment of various infections, including respiratory infections, skin and soft tissue infections, and sexually transmitted infections. Increases in morbidity and mortality associated with infections by multidrug-resistant organisms have highlighted the need for new antibiotics. In 2018, three novel tetracyclines were approved by the FDA: eravacycline, omadacycline, and sarecycline. This review discusses the pharmacological properties and microbiological and clinical aspects of these new tetracyclines.

Medical laboratory scientists (MLS) often begin their careers employed in a hospital or public health laboratory, where employment qualifications and standards are dictated by the accrediting body. MLS who specialize in clinical microbiology have multiple career paths that can lead to a very successful and satisfying career. This review covers some details of the educational requirements and certifications required for employment within various hospital laboratory work environments and opportunities for career advancement. Alternative career paths are also highlighted, opening first with hospital departments adjacent to the clinical microbiology laboratory, such as quality assurance and infection prevention and control. In addition, careers in public health laboratories, research laboratories, scientific communication, project management, government, and the food industry, as well as foundation and non-profit work, are highlighted. Various technical career pathways within the industry and biotechnology sectors are described. The review concludes by acknowledging that for some individuals, career goals may not be fully realized without the pursuit of higher education, and it provides some overarching career advice for taking the next step toward a new career pathway.

The introduction of sophisticated molecular technologies (16S rRNA gene sequencing, matrix-assisted laser desorption ionization–time of flight [MALDI-TOF], and whole-genome sequencing) into many clinical and diagnostic microbiology laboratories has brought with it enhanced capabilities for the accurate identification of many prokaryotic species not resolvable by common phenotypic or commercially automated methods. Along with this heightened capacity to provide highly accurate bacterial identifications have come some indirect consequences that may not be entirely appreciated by the scientific community. Some examples of these consequences are a transitional approach to training and a different skill set for current laboratorians, a quickly changing bacterial taxonomy, and peer-reviewed literature requiring much closer scrutiny. This article provides an overview of the present situation and challenges to microbiologists as the field moves forward.

Group A Streptococcus, or Streptococcus pyogenes, is a facultatively anaerobic Gram-positive coccus and one of the most common causes of bacterial infection in humans. The introduction of antibiotics has greatly reduced the morbidity and mortality associated with this organism, but despite uniform susceptibility to treatments of choice, it remains a significant human pathogen. It is particularly problematic in underdeveloped and lower socioeconomic status countries, where hygiene may be suboptimal. This review covers a wide range of topics related to the organism, including diagnosis, treatment, and clinical manifestations. Where possible, the review addresses less conventional and often controversial topics that have not been extensively reviewed elsewhere, such as the activity of trimethoprim sulfamethoxazole against the species, penicillin tolerance, and the use of protein synthesis inhibitors to reduce toxin production and improve outcomes.

The indications for and interest in self-collection of specimens, such as blood, saliva, urine, stool, and anogenital specimens, for clinical laboratory testing are vast (especially in the post-pandemic era). A need for innovation, combined with convenience for patients, clinicians, and researchers, opened the doors for a wave of self-collection devices to flood the market in early 2020. Many of the devices discussed in this review are registered by the U.S. Food and Drug Administration (FDA) or have emergency use authorization for diagnostic testing in clinical laboratories. While many self-collection devices were evaluated for collection of specimens for SARS-CoV-2 testing, they can be used to collect samples for many other serologic, molecular, or other diagnostic methods following completion of necessary laboratory validation studies. The advantages of these devices, such as convenience and access, must be balanced with added cost, challenges of specimen stability, and manual processing in the laboratory, all of which are discussed in this review.

Despite pneumonia being a leading cause of morbidity and mortality worldwide, diagnostics remains a challenge, hindering rapid organism identification and subsequent effective treatments. Current microbiological methods include culture, serology, and limited molecular panels. While helpful, these methods are unable to address the full range of potential pathogens (e.g., fastidious or noncultivable organisms or uncommon organisms not included in current panels). Metagenomic next-generation sequencing (mNGS) is a molecular technique that analyzes and compares the nucleic acid content in a patient sample to a reference database of organisms that may include bacteria, viruses, fungi, and/or parasites, depending on the mNGS technology used. By bypassing the limitations of culture and targeted molecular assays, mNGS offers the potential to identify countless organisms directly from a patient specimen to aid in the diagnosis of an infectious process. Although promising, mNGS does have considerable limitations related to cost, interpretation, standardization, clinical relevance, turnaround time (TAT), and widespread availability. Thus, these factors should be considered prior to implementing mNGS for clinical use. Moreover, additional studies are required to fully understand the clinical and epidemiological impact of mNGS for the diagnosis of infectious diseases, including respiratory infections.