Characterization of highly antimicrobial-resistant clinical pneumococcal isolates recovered in a Chinese hospital during 2009–2010

Abstract

Ninety-one consecutive pneumococcal isolates (primarily from sputum), recovered in Chongqing Southwest Hospital during a 12 month period in 2009-2010 from individuals of all ages with suspected cases of pneumococcal disease, were subjected to PCR-serotyping, Quellung reaction serotyping, antimicrobial-susceptibility testing and multilocus sequence typing (MLST). Although 20 different serotypes were observed, most isolates (69, 75.8 %) were of serotypes included in the pneumococcal 13-valent conjugate vaccine (PCV13), including 33 of the 46 (71.7 %) isolates recovered from individuals less than 5 years of age. The prevalent serotypes were 19F (34 %), 19A (9.9 %), 6B (9.9 %), 23F (7.7 %), 14 (6.6 %) and 6A (4.4 %). PCR-determined serotypes were in agreement with Quellung testing, with the exception of two serotype 33C isolates. Most or all isolates within each PCV13 serotype were represented by one genotype, with the globally disseminated MLST sequence types (STs) ST271, ST320, ST90 and ST81 each accounting for the highly resistant isolates within serotypes 19F, 19A, 6B and 23F, respectively. Sixty-six (72.5 %) isolates were resistant to combinations of b-lactam antibiotics (BLAs). A total of 63 of these 66 (95.5 %) BLA-resistant isolates were of serotypes included in PCV13; however, 3 serogroup 15 isolates were also BLA-resistant. Most isolates (88/91596.7 %) were resistant to erythromycin and clindamycin. The majority of isolates were also resistant to tetracycline (76, 84 %) and to cotrimoxazole (67, 74 %). This work revealed that the majority of antimicrobial-resistant isolates (50/91554.9 %) recovered in this Chinese hospital were represented by four global clones. Serotypes for these as well as more obscure strains were readily determined by using PCR.

Regional epidemiology of invasive pneumococcal disease in Asian adults: epidemiology, disease burden, serotype distribution, and antimicrobial resistance patterns and prevention

“…In China, the prevalent serotypes were 19F, 19A, 6B, 23F, 14, and 6A in isolates taken from 2009 to 2010. 73 In a recent report from Thailand, out of 172 isolates taken between 2006 and 2009, the most common serotypes were 6B, 23F, 14, 19F, and 19A in patients <5 years old, and 6B, 19A, 23F, 4, and 9 V in patients >65 years old. 74 Another study from Thailand found that, at the Phramongkutklao Hospital in Bangkok, the most common serotype in patients from 2004 to 2008 was 6B.…”

Genetic Analyses of Penicillin Binding Protein Determinants in Multidrug-Resistant Streptococcus pneumoniae Serogroup 19 CC320/271 Clone with High-Level Resistance to Third-Generation Cephalosporins

“…(15). The increasing rates of nonsusceptibility to ␤-lactams over the past years in our regions warrant concern.…”

Biological and Epidemiological Features of Antibiotic-Resistant Streptococcus pneumoniae in Pre- and Post-Conjugate Vaccine Eras: a United States Perspective

“…These PMEN MDR CCs represented PCV7 serotypes that thrived and disseminated throughout the world during the 1980s and 1990s (25). Nonvaccinated or poorly vaccinated populations in countries with unrestricted antibiotic availability continue to have high proportions of highly resistant disease isolates within these clonal complexes (62,287). As shown in Fig.…”

“…Currently, Ͼ40% of isolates are penicillin resistant in several countries that lack significant conjugate vaccine coverage (56)(57)(58)(59)(60)(61)(62). Studies have found that previous use of ␤-lactam antibiotics (63), extremes of age (e.g., children Ͻ5 years of age and the elderly) (63)(64)(65)(66), and child care attendance (in a carriage study using PNSP defined as an MIC of Ͼ0.06 g/ml) (65) were associated with penicillin-nonsusceptible pneumococcal infections.…”