Detection, Identification and Diagnostic Characterization of the Staphylococcal Small Colony-Variant (SCV) Phenotype

Bibliographic Details
Title: Detection, Identification and Diagnostic Characterization of the Staphylococcal Small Colony-Variant (SCV) Phenotype
Authors: Karsten Becker
Source: Antibiotics, Vol 12, Iss 9, p 1446 (2023)
Publisher Information: MDPI AG, 2023.
Publication Year: 2023
Collection: LCC:Therapeutics. Pharmacology
Subject Terms: small-colony-variant, Staphylococcus aureus, coagulase-negative staphylococci, diagnostics, cultivation, identification, Therapeutics. Pharmacology, RM1-950
More Details: While modern molecular methods have decisively accelerated and improved microbiological diagnostics, phenotypic variants still pose a challenge for their detection, identification and characterization. This particularly applies if they are unstable and hard to detect, which is the case for the small-colony-variant (SCV) phenotype formed by staphylococci. On solid agar media, staphylococcal SCVs are characterized by tiny colonies with deviant colony morphology. Their reduced growth rate and fundamental metabolic changes are the result of their adaptation to an intracellular lifestyle, regularly leading to specific auxotrophies, such as for menadione, hemin or thymidine. These alterations make SCVs difficult to recognize and render physiological, biochemical and other growth-based methods such as antimicrobial susceptibility testing unreliable or unusable. Therefore, diagnostic procedures require prolonged incubation times and, if possible, confirmation by molecular methods. A special approach is needed for auxotrophy testing. However, standardized protocols for SCV diagnostics are missing. If available, SCVs and their putative parental isolates should be genotyped to determine clonality. Since their detection has significant implications for the treatment of the infection, which is usually chronic and relapsing, SCV findings should be specifically reported, commented on, and managed in close collaboration with the microbiological laboratory and the involved clinicians.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2079-6382
Relation: https://www.mdpi.com/2079-6382/12/9/1446; https://doaj.org/toc/2079-6382
DOI: 10.3390/antibiotics12091446
Access URL: https://doaj.org/article/a2ed91f8f957482489882a410464d897
Accession Number: edsdoj.2ed91f8f957482489882a410464d897
Database: Directory of Open Access Journals
More Details
ISSN:20796382
DOI:10.3390/antibiotics12091446
Published in:Antibiotics
Language:English