Penicillin-Resistant and Multidrug-Resistant Streptococcus pneumoniae in a Pediatrie Hospital in Zagreb, Croatia

Abstract

Sixty-four penicillin-resistant Streptococcus pneumoniae isolates [benzylpenicillin minimal inhibitory concentrations (MICs) between 0.05 and 1.6 micrograms/ml] recovered at the Pediatric Hospital "Dr. Fran Mihaljevic" in Zagreb, Croatia between October 1990 and March 1993 were analyzed for serotype, antibiotic susceptibility patterns, and chromosomal relatedness using pulsed-field gel electrophoretic (PFGE) analysis of chromosomal DNA fragmented by digestion with the SmaI endonuclease. Hospital "Dr. Fran Mihaljevic" services the capital of Croatia and its vicinity. Most of the isolates were from nasopharyngeal carriage, but several isolates were from otitis media, sinusitis, and meningitis. Most isolates belonged to either serotype 23F (36/64) or 19F (12/64); the rest, including three 15C isolates, were in 11 additional distinct serotypes. The overwhelming majority (25/36) of the serotype 23F isolates had penicillin MIC values of 1-2 micrograms/ml and shared variants of a common PFGE pattern, closely related to the PFGE identified in multiresistant pneumococci of the same serotype with wide geographic spread to Spain, Portugal, France, and the United States. This group of bacteria was also resistant to tetracycline, chloramphenicol, and sulfamethoxazole/trimethoprim. In contrast to the relative genetic and phenotypic homogeneity of the more highly penicillin resistant isolates, pneumococci with penicillin MICs between 0.5 and 0.4 microgram/ml (29/64) were distributed in 13 different serotypes and as many as 20 distinct PFGE patterns.

Molecular Typing ofStreptococcus pneumoniaein Northeastern Romania: Unique Clones ofS. pneumoniaeIsolated from Children Hospitalized for Infections and from Healthy and Human Immunodeficiency Virus–Infected Children in the Community

“…However, because PFGE patterns were not available in that publication, the genetic similarity between the strains could not be verified. No resemblance with the ROM-1 and ROM-12 clones described here was found when we compared them with other unique penicillin-resistant clones of pneumococci, such as the predominantly 19A clone identified in Hungary [25] (A.T., unpublished data), the serotype 14 and 19A clones in the Czech Republic and Slovakia [26], the 2 internationally spread clones with serotypes 23F and 9 or 14 detected in many countries, including Croatia [27] and Bulgaria [28], and the several other Bulgarian clones [28].…”

Nomenclature of Major Antimicrobial-Resistant Clones of Streptococcus pneumoniae Defined by the Pneumococcal Molecular Epidemiology Network

“…This phenomenon has been particularly highlighted by the worldwide spread of the serotype 23F pneumococcal clone (Spain 23F -1), first identified in Spain in the early 1980s (37) and resistant to penicillin, chloramphenicol, and tetracycline (and sometimes erythromycin). This successful clone has now been found in the United States (26, 37), South Africa (23), the United Kingdom (7), South America (5, 6, 12, 43), several other countries in Europe (29,30,42,46,48,50,58,61), and the Far East (34,47,59). Serotype 19F (7), 14 (4), 19A (9), 9N (40), and 3 (40) and serogroup 6 (54) variants of this clone have also been reported in various regions of the world.…”

Clonally Related Penicillin-Nonsusceptible Streptococcus pneumoniae Serotype 14 from Cases of Meningitis in Salvador, Brazil

“…Clonally related S. pneumoniae strains implicated in the geographic spread of penicillin have generally been found to be highly resistant [39][40][41]. Studies from several countries have shown that S. pneumoniae strains with intermediate-level resistance to penicillin demonstrate large variations in their genetic background [42][43][44]. However, in Brazil, analysis of strains from reference laboratory collections by pulsed-field gel electrophoresis has identified clusters of isolates with intermediatelevel resistance, including those belonging to serotype 14, that were obtained from geographically distinct regions [45].…”