Group A streptococcal invasive disease in England and Wales

Streptococcal toxic shock syndrome: a description of 14 cases from North Yorkshire, UK

OBJECTIVE

To analyze the clinical and laboratory features of patients diagnosed with streptococcal toxic shock syndrome (TSS) in North Yorkshire from 1986 to 1999.

METHODS

Records of patients with features satisfying the published criteria for streptococcal TSS were reviewed from laboratory and clinical records made at the time and from the hospital case notes. Isolates of streptococci were analyzed for serotype and genes encoding for the production of streptococcal pyrogenic exotoxins.

RESULTS

Fourteen patients satisfied the entry criteria. In one district, where the data were complete, the annual incidence of detected streptococcal TSS rose from 1.1 to 9.5 cases per million population in the 1990s. TSS was associated with various M serotypes of group A streptococci and various exotoxin genotypes. Two cases (14% of the series) were associated with severe group G streptococcal infection. The fatality rate was 64%, and the mode of time to death was 4 days. Local tissue necrosis occurred in 71% of cases, including necrotizing fasciitis, intrathoracic and intra-abdominal forms. Non-steroidal anti-inflammatory drugs (NSAIDs) had been taken around the time of onset of disease by 92% of the patients with TSS.

CONCLUSIONS

There has been a dramatic increase in the number of detected cases of streptococcal TSS over the 14 years since the first case was recognized here. There was a wide range of invasive forms of infection, a high fatality rate even in fit young adults, and a rapid course from onset to death. There was a high association of TSS with aggressive streptococcal infection producing local tissue necrosis.

High-resolution genotyping of Streptococcus pyogenes serotype M1 isolates by fluorescent amplified-fragment length polymorphism analysis

We have used fluorescent amplified-fragment length polymorphism (FAFLP) analysis to subtype clinical isolates of Streptococcus pyogenes serotype M1. Established typing methods define most M1 isolates as members of a clone that has a worldwide distribution and that is strongly associated with invasive diseases. FAFLP analysis simultaneously sampled 90 to 120 loci throughout the M1 genome. Its discriminatory power, precision, and reproducibility were compared with those of other molecular typing methods. Irrespective of disease symptomatology or geographic origin, the majority of the clinical M1 isolates shared a single ribotype, pulsed-field gel electrophoresis macrorestriction profile, and emm1 gene sequence. Nonetheless, among these isolates, FAFLP analysis could differentiate 17 distinct profiles, including seven multi-isolate groups. The FAFLP profiles of M1 isolates reproducibly exhibited between 1 and more than 20 amplified fragment differences. The high discriminatory power of genotyping by FAFLP analysis revealed genetic microheterogeneity and differentiated otherwise "identical" M1 isolates as members of a clone complex.