Age-related differences in clinical characteristics of invasive group G streptococcal infection: Comparison with group A and group B streptococcal infections

PLoS One. 2019 Mar 7;14(3):e0211786. doi: 10.1371/journal.pone.0211786. eCollection 2019.


Purpose: Invasive Group G streptococcal infection (iGGS) has increasingly been recognized as a cause of severe disease, mainly among elderly people with chronic illnesses. This study aimed to examine age-related differences in clinical characteristics of iGGS and describe its characteristics among very elderly individuals (≥80 years).

Methods: Fifty-four iGGS patients for whom detailed clinical information was available were identified from 2002 to 2014 in a tertiary care hospital in Japan. iGGS (n = 54) was compared with invasive Group A (iGAS; n = 17) and B streptococcal infection patients (iGBS; n = 52) based on patient age.

Results: The incidence of iGGS in our catchment area significantly increased during the study period. The prevalence of iGGS in the very elderly population was higher than that of iGAS or iGBS (p<0.001). Among iGGS patients, cardiovascular disease, chronic kidney disease, oxygen demand, and bacteremia with unknown focus of infection were more frequent in the very elderly population (p = 0.009, p = 0.02, p = 0.04, and p = 0.04, respectively). Altered mental status was present in half of iGGS patients aged ≥60 years (p = 0.03). In contrast, alcohol drinking and liver cirrhosis were significantly more frequent in patients with iGGS aged <60 years than in other age groups (p<0.001, p = 0.001, respectively). Levofloxacin resistance in GBS isolates was significantly more frequent among very elderly patients than among other age groups (p<0.001).

Conclusions: The burden of iGGS has been increasing in our catchment area. Different iGGS-associated clinical characteristics were found in each age group. Unclear and atypical clinical manifestations and syndromes were likely to be observed in very elderly patients. Alcohol drinking and liver cirrhosis may contribute to iGGS even in patients aged <60 years. Understanding these age-related differences could be helpful for optimal diagnosis and treatment.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Child
  • Child, Preschool
  • Drug Resistance, Bacterial
  • Female
  • Humans
  • Incidence
  • Infant
  • Infant, Newborn
  • Male
  • Middle Aged
  • Prevalence
  • Retrospective Studies
  • Streptococcal Infections / drug therapy
  • Streptococcal Infections / epidemiology*
  • Streptococcus agalactiae
  • Streptococcus pyogenes
  • Young Adult

Grant support

This study was supported by a grant from Japan's National Center for Global Health and Medicine (grant no. 29S200401).