Nutritionally Variant Streptococci- its Clinical Relevance and Treatment Options: A Mini-Review

Abstract

Nutritionally variable streptococci (NVS) were assumed to be nutritional mutants of the viridans group of streptococci, but they are now considered as other Streptococcus species. Due to their difficult nature, to date, the detection and treatment of NVS are challenging. This review aims at a compilation of a comprehensive study on literature reporting the microbiological characteristics of NVS species, their detection, and treatment strategies with an emphasis on large-scale research experimentations According to the literature, the classification of these Streptococci has changed several times, interpreting the scientific literature of Abiotrophia and Granulicatella spp. NVS strains exhibit pleomorphic cellular morphologies, and they can be distinguished from other streptococci by their biochemical reactions and molecular tests. They have been isolated from clinical specimens including pus, synovial fluid, and blood, in addition to their involvement in endocarditis. Treatment of NVS is challenging due to its difficult nature and the complexity of antimicrobial susceptibility testing. Early diagnosis is critical for initiating proper therapy and avoiding fatal consequences. Microbiologists and clinicians ought to be cautious of these isolates, which are easy to overlook due to their difficult nature and the challenges in retrieving from clinical samples. Hence large-scale research is required to identify additional detection techniques, infrastructure, and treatment options.