Invasive Group B Streptococcal Disease in Non-pregnant Adults

Abstract

Streptococcus agalactiae, commonly referred as group B Streptococcus (GBS), is a major cause of neonatal sepsis and infections in pregnant women. However, the number of invasive infections in non-pregnant adults is growing. Elderly patients and those with chronic underlying conditions, such as diabetes mellitus or compromised immune defence, are at increased risk of invasion. The spectrum of clinical manifestations is broad and includes necrotizing fasciitis and toxic shock syndrome. Although, primary bacteremia and skin and soft-tissue infections are the most frequently reported diagnosis. This article reviews the epidemiology, pathogenesis and treatment of invasive GBS disease in non-pregnant adults, with an emphasis on skin and soft-tissue infections.

Impact of diabetes and poor glycaemic control on risk of bacteraemia with haemolytic streptococci groups A, B, and G

“…7 Recently, Skoff et al used population-based surveillance in selected counties in 10 US states to examine trends in adult GBS disease during the period 1990e2007. 3 Diabetes was present in a striking 44.4% of GBS disease cases in 2007, increasing N/A: adjustment not possible due to sparse data.…”

“…6 Other shared risk factors are physical inactivity and obesity, which may lead to venous oedema and/or lymphoedema followed by relapsing erysipelas/cellulitis and ulcers of the leg. 7,34 Diabetes per se may lead to peripheral vascular disease and neuropathy, and at least 15% of patients with diabetes will develop a foot ulcer in their lifetime. 35,36 Moreover, diabetes is a major risk factor for chronic heart failure 37 that subsequently may lead to venous oedema, leg ulcers and infections.…”

“…In particular, several studies have indicated a strikingly high prevalence of diabetes among patients with invasive HS disease. 7 For GBS invasive disease, many case series from both North America, Asia and Europe have reported diabetes prevalences of approximately 30%. 8e15 Among patients with severe GAS infections, 8% (with a wide range of 0%e 22%) had diabetes in a recent 2-year prospective surveillance study in 11 European countries.…”

“…17 Diabetic persons may have increased susceptibility to HS bacteraemia for several reasons, including hyperglycaemia and related effects on phagocytic function and cellmediated immunity, and coexisting morbidities and diabetic complications such as foot and leg ulcers. 7 The impact of poor glycaemic control on the risk of HS bacteraemia in diabetic persons has to our knowledge never been examined. Given the rising incidence of HS bacteraemia and the rapidly increasing prevalence of diabetes worldwide, 18 it is important to quantify the risk of HS bacteraemia associated with diabetes and poor glycaemic control.…”

Characterization of Invasive and Colonizing Isolates of Streptococcus agalactiae in East African Adults

“…In adults, S. agalactiae causes skin and soft tissue infections, bacteremia, urinary tract infections, pneumonia, osteomyelitis, meningitis, endocarditis, and streptococcal toxic shock syndrome (2,6,18,20). Risk factors associated with invasive GBS in adults are old age, diabetes mellitus, neurologic diseases, cirrhosis or other liver diseases, stroke, breast cancer, and renal failure (7,22,23). S. agalactiae colonizes the lower gastrointestinal and genitourinary tracts of 30 to 50% of healthy adults (26), and an estimated 20 to 30% of all pregnant women are carriers (25).…”