Genotypes of invasive pneumococcal isolates recently recovered from Italian patients

We examined 73 recent invasive pneumococcal isolates within selected areas of Italy for genotypic variability. Thirty-three genomic macrorestriction types were found, three of which represented multiple serotypes. Restriction fragment patterns of pbp2b, pbp2x, and pspA were conserved within the majority of isolates that shared macrorestriction types. Of the nine macrorestriction types found among the 22 penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) isolates, seven comprised isolates with allelic profiles showing five to seven allelic matches to profiles in the multilocus sequence typing database (www.mlst.net); however, three of the seven profiles represented serotypes not previously associated with these clonal clusters. Two PNSP macrorestriction types represented new clones with unique allelic profiles. Allelic profiles obtained from isolates of 3 of the 25 macrorestriction types found among the 51 penicillin-susceptible S. pneumoniae (PSSP) isolates were closely related to previously described profiles. One PSSP isolate was a novel type 24F isolate related to the multiresistant clone France(9V)-3. This work reports new PNSP strains and new serotype-clone associations.