Gastric emptying of preterm neonates receiving domperidone.

OBJECTIVES: Immature gut motility in very low birth weight infants causes feeding intolerance. We evaluated the effect of domperidone, a prokinetic agent, on gastric emptying in very low birth weight infants. METHODS: The study was conducted in a crossover design. Gastric emptying was assessed ultrasonographically by measuring the time it took the antral cross sectional area of the stomach to reach half of the value of the 1st measurement on 2 occasions: (1) upon administration of domperidone (0.3 mg/kg/8 h p.o.) for at least 2 days and (2) while patients received an equal quantity of sterile water. 11 infants were randomly assigned to receive domperidone before the 1st measurement and the remaining afterwards. There was a 3-5 day interval between the 2 measurements. At the time when both measurements were performed, every neonate had been receiving the same quantity and quality of milk. 12 infants were formula-fed while 10 were fed their own mother's supplemented milk. RESULTS: 22 infants with a mean (SD) birth weight of 1,377 g (319) and a mean (SD) gestational age of 30.2 weeks (2.1) were studied. The mean (SD) antral cross sectional area half-value time (in minutes) was 47.6 (23.9) in the domperidone group and 68.2 (25.5) in the control group (p = 0.008). There was no significant difference between formula-fed neonates and neonates fed their own mother's milk in either group. CONCLUSIONS: Domperidone significantly reduces gastric emptying in preterm neonates, and this may account for its effect in cases of disturbances related to gut motility.

Molecular epidemiology of penicillin-susceptible non-beta-lactam-resistant Streptococcus pneumoniae isolates from Greek children.

A total of 128 Streptococcus pneumoniae isolates that were susceptible to penicillin but resistant to non-beta-lactam agents were isolated from young carriers in Greece and analyzed by antibiotic susceptibility testing, serotyping, restriction fragment end labeling (RFEL), and antibiotic resistance genotyping. The serotypes 6A/B (49%), 14 (14%), 19A/F (11%), 11A (9%), 23A/F (4%), 15B/C (2%), and 21 (2%) were most prevalent in this collection. Of the isolates, 65% were erythromycin resistant, while the remaining isolates were tetracycline and/or trimethoprim-sulfamethoxazole resistant. Fifty-nine distinct RFEL types were identified. Twenty different RFEL clusters, harboring 2 to 19 strains each, accounted for 76% of all strains. Confirmatory multilocus sequence typing analysis of the genetic clusters showed the presence of three international clones (Tennessee(23F)-4, England(14)-9, and Greece(6B)-22) representing 30% of the isolates. The erm(B) gene was present in 70% of the erythromycin-resistant isolates, whereas 18 and 8% contained the mef(A) and mef(E) genes, respectively. The pneumococci representing erm(B), erm(A), and mef genes belonged to distinct genetic clusters. In total, 45% of all isolates were tetracycline resistant. Ninety-six percent of these isolates contained the tet(M) gene. In conclusion, penicillin-susceptible pneumococci resistant to non-beta-lactams are a genetically heterogeneous group displaying a variety of genotypes, resistance markers, and serotypes. This suggests that multiple genetic events lead to non-beta-lactam-resistant pneumococci in Greece. Importantly, most of these genotypes are capable of disseminating within the community.

Development of macrolide resistance by ribosomal protein L4 mutation in Streptococcus pyogenes during miocamycin treatment of an eight-year-old Greek child with tonsillopharyngitis.

Streptococcus pyogenes isolates with the same pulsed-field patterns were recovered from the throat cultures of a child with tonsillopharyngitis before and after treatment with miocamycin, a 16-membered macrolide. The initial isolate was macrolide-susceptible, but the isolates after the treatment were resistant to 14 and 15-membered macrolides and had two amino acid (65WR66) deletions in ribosomal protein L4.

High prevalence of erythromycin resistance of Streptococcus pyogenes in Greek children.

BACKGROUND: Macrolide resistance among Streptococcus pyogenes strains is increasing in many European countries. Greece was not considered a country with high prevalence of macrolide-resistant S. pyogenes strains, and until now the genetic mechanism of resistance was unknown. METHODS: During the 25-month period from December, 1998, to December, 2000, pharyngeal cultures for S. pyogenes were performed on 743 Greek children with the clinical diagnosis of pharyngitis. The children were 1 to 16 years old (median age, 7 years) and were living in Central and Southern Greece. S. pyogenes isolates were tested for their susceptibility to erythromycin, clarithromycin, azithromycin, clindamycin, penicillin G, amoxicillin/clavulanate and cefprozil. The erythromycin-resistant isolates were further studied for their genetic mechanism of resistance by means of PCR. RESULTS: Of a total of 275 S. pyogenes isolates recovered, 105 (38%) were erythromycin-resistant (MIC > or = 1 microgram/ml) [corrected], with 54, 45 and 1% of them carrying mef(A), erm(A) [subclass erm(TR)] and erm(B) gene, respectively. The prevalence of erythromycin-resistant strains was 29 and 42% during the time periods December, 1998, to December, 1999, and January, 2000, to December, 2000, respectively. All erythromycin-resistant isolates were also resistant to clarithromycin and azithromycin. The isolates carrying the erm(A) gene were inducibly resistant to clindamycin. The 275 S. pyogenes isolates had ceprozil MICs < or = 0.032 microgram/ml. CONCLUSIONS: The current high (38%) prevalence of erythromycin-resistant S. pyogenes in Central and Southern Greece requires continuous surveillance and careful antibiotic policy.

Sterile cerebrospinal fluid pleocytosis in young infants with urinary tract infection.

BACKGROUND: During the first 3 months of life febrile infants are subjected to sepsis workup, which includes evaluation for urinary tract infection (UTI) and meningitis. We investigated the existence of concomitant meningeal inflammation in infants younger than 90 days old affected with UTI. METHODS: We reviewed the medical records of all infants younger than 90 days old, who were hospitalized for UTI from January, 1990, to January, 2001. For the diagnosis of sterile cerebrospinal fluid (CSF) pleocytosis, the child's age, the CSF total white blood cell (WBC) count and the CSF absolute neutrophil count were taken into consideration. CSF pleocytosis was defined as the presence of > or = 35, > or = 21 and > or = 15 WBC/mm3 of CSF during the first, second and third month of life, respectively. The CSF Gram-stained smear, latex agglutination test and bacterial culture were negative. RESULTS: Sterile CSF pleocytosis was found in 15 (12.8%) of 117 infants with UTI who had had a lumbar puncture included in their initial laboratory evaluation. The 15 infants had a median age +/- semiinterquartile range of 40 +/- 25 days (range, 4 to 75 days). In these infants the median CSF WBC count +/- semiinterquartile range was 55 +/- 125/mm3 (range, 21 to 1,270/mm3). CONCLUSIONS: Sterile CSF pleocytosis was found in 12.8% of infants younger than 90 days old with UTI. The pathogenesis of this meningeal inflammation is not fully understood. Although bacterial infection of the subarachnoid space, with low bacterial seeding, cannot be excluded, at least in some cases, it is possible that CSF pleocytosis in some of the infants with UTI is mainly caused by the endotoxin of Gram-negative or other inflammation-inducing molecules of Gram-positive urine pathogens.

Clonal relationships among penicillin-susceptible, multiresistant serotype 6B Streptococcus pneumoniae isolates recovered in Greece and France.

In January 1996 the emergence of penicillin-susceptible, multiresistant serotype 6B Streptococcus pneumoniae isolates resistant to chloramphenicol, tetracycline, erythromycin, clindamycin and trimethoprim-sulfamethoxazole was observed in young carriers in the city of Patras, located in the southwestern region of Greece. Later, a significant spread of pneumococci with this unusual phenotype was noted in carriers living in various other areas of the country. Using restriction fragment length polymorphism of the ribosomal RNA genes, clonal relationships were found between these Greek strains and serotype 6B penicillin-susceptible, multiresistant pneumococci isolated in France between January 1992 and September 1996. The French and Greek isolates appear to have a common ancestry.

Molecular epidemiology of penicillin-susceptible, multidrug-resistant serotype 6B pneumococci isolated from children in Greece.

Since January 1996, and over a 3-year time span, a significant spread of serotype 6B multidrug-resistant (MDR) pneumococci, susceptible to penicillin and resistant to erythromycin, clindamycin, tetracycline, chloramphenicol, and trimethoprim-sulfamethoxazole, was noted in young carriers living in central and southern Greece. Using restriction fragment end labeling and penicillin binding protein (PBP) genotyping, we studied 41 serotype 6B penicillin-susceptible MDR pneumococci isolated during two independent studies in Greece. Forty (98%) of these 41 isolates were strongly related, representing a single lineage (genetic relatedness, > or = 91%). The Greek isolates were closely related (genetic relatedness, approximately 91%) to the penicillin-resistant MDR clone of serotype 6B that spread from Spain to Iceland in the late 1980s. Moreover, the Greek group of isolates was genetically distinct (genetic relatedness, < or = 83%) from other penicillin-susceptible or -resistant serotype 6B strains from various parts of the world. All serotype 6B penicillin-susceptible MDR isolates displayed a penicillin-susceptible PBP 1A-2B-2X genotype. Our findings suggest that the penicillin-susceptible MDR 6B clone that was found in Greece between the years 1996 and 1999 represents the ancestor of the pandemic penicillin-resistant MDR clone 6B.

Identification of an erm(A) erythromycin resistance methylase gene in Streptococcus pneumoniae isolated in Greece.

In a serotype 11A clone of erythromycin-resistant pneumococci isolated from young Greek carriers, we identified the nucleotide sequence of erm(A), a methylase gene previously described as erm(TR) in Streptococcus pyogenes. The erm(A) pneumococci were resistant to 14- and 15-member macrolides, inducibly resistant to clindamycin, and susceptible to streptogramin B. To our knowledge, this is the first identification of resistance to erythromycin in S. pneumoniae attributed solely to the carriage of the erm(A) gene.

Molecular epidemiology of penicillin-nonsusceptible Streptococcus pneumoniae among children in Greece.

A total of 145 penicillin-nonsusceptible Streptococcus pneumoniae strains were isolated from young carriers in Greece and analyzed by antibiotic susceptibility testing, serotyping, restriction fragment end labeling (RFEL), and penicillin-binding protein (PBP) genotyping. The serotypes 23A and 23F (54%), 19A and 19F (25%), 9V (5%), 15A, 15B, and 15C (4%), 6A and 6B (4%), and 21 (4%) were most prevalent in this collection. Fifty-three distinct RFEL types were identified. Sixteen different RFEL clusters, harboring 2 to 32 strains each, accounted for 82% of all strains. Eight of these genetic clusters representing 60% of the strains were previously identified in other countries. A predominant lineage of 66 strains (46%) harboring five RFEL types and the serotypes 19F and 23F was closely related to the pandemic clone Spain(23F)-1 (genetic relatedness of > or =85%). Another lineage, representing 11 strains, showed close genetic relatedness to the pandemic clone France(9V)-3. Another lineage of 8 serotype 21 strains was Greece specific since the RFEL types were not observed in an international collection of 193 genotypes from 16 different countries. Characterization of the PBP genes pbp1a, pbp2b, and pbp2x revealed 20 distinct PBP genotypes of which PBP type 1-1-1, initially observed in the pandemic clones 23F and 9V, was predominantly present in 11 RFEL types in this Greek collection of penicillin-nonsusceptible strains (55%). Sixteen PBP types covering 52 strains (36%) were Greece specific. This study underlines the strong contribution of penicillin-resistant international clones to the prevalence and spread of penicillin-nonsusceptible pneumococci among young children in Greece.

Mediterranean clone of penicillin-susceptible, multidrug-resistant serotype 6B Streptococcus pneumoniae in Greece, Italy and Israel.

In 1996, 19 isolates of serotype 6B Streptococcus pneumoniae with a unique resistance pattern were found in carriers attending daycare centres in Patras, Southwestern Greece. These isolates were penicillin susceptible but resistant to chloramphenicol, tetracycline, erythromycin, clindamycin and trimethoprim-sulphamethoxazole. Subsequently, isolates with the same characteristics were found in 23 additional carriers in central and southern Greece in 1997-98 as well as in 19 carriers in central Italy in 1997, and in seven carriers in southern Israel in 1998. Carriers were all children under 6 years of age, attending daycare centres or outpatient hospital visits. The relatedness of the isolates was determined on representative isolates from the three countries by pulsed-field gel electrophoresis of SmaI digests of chromosomal DNA. Most Greek isolates were identical to each other, while isolates from Italy and Israel showed one to three band differences, with all isolates being closely related to each other as well as to the isolates from Greece. We have therefore documented the presence of this unique clone of S. pneumoniae in these three countries and have named this the 'Mediterranean' clone. While isolates appear to have a common origin, their source and direction of spread are unknown. However, isolates from Italy showed the most diversity, suggesting that this clone had been present in that country for a longer period than it had been in Greece.

Antimicrobial use and colonization with erythromycin-resistant Streptococcus pneumoniae in Greece during the first 2 years of life.

We evaluated nasopharyngeal colonization with erythromycin-resistant Streptococcus pneumoniae during the first 2 years of life in central and southern Greece. Of 2448 children studied from February 1997 to February 1999, 766 (31%) carried 781 pneumococcal isolates. Ninety-five (3.9%) of the children attended day care centers. Eighteen percent of the pneumococci were resistant to erythromycin (minimal inhibitory concentration 1 to >128 microg/mL), with 67.9% of them carrying the erm(B) gene and 29.2% mef(A) gene products. Four strains possessed neither the erm(B) nor the mef(A) gene. Multidrug resistance occurred in 97% and 40% of isolates carrying the erm(B) and mef(A) gene, respectively. An association was found between the erm(B) gene and serotypes 6B and 23F and between the mef(A) gene and serotypes 14 and 19F. A significant relationship existed between carriage of erythromycin-resistant pneumococci and use of macrolides or beta-lactams in the previous 3 months; the association was strongest when macrolide therapy was administered during the last month (odds ratio, 5.92; P=.0001). The findings indicate the necessity of a judicious use of both macrolides and beta-lactams in young children to reduce the colonization with erythromycin-resistant pneumococci and the subsequent spread of such strains to the community.

Carriage of antibiotic-resistant Streptococcus pneumoniae in Greek infants and toddlers.

The prevalence, resistance patterns and serotypes of antibiotic-resistant Streptococcus pneumoniae strains recovered from Greek carriers under 24 months of age were studied. From February 1997 to April 1998, nasopharyngeal cultures were performed in 1,269 children (ages 2-23 months, median 11 months) living in various areas of central and southern Greece. Resistance (including both intermediate and resistant isolates) to one or more antimicrobial agents was found in 132 of the 421 (31%) Streptococcus pneumoniae isolates, as follows: penicillin, 9% intermediate, 7.6% resistant; cefotaxime, 5.2% intermediate, 0.5% resistant; erythromycin, 0.7% intermediate, 18.1% resistant; clindamycin, 0.2% intermediate, 12.4% resistant; tetracycline, 0.7% intermediate, 16.4% resistant; chloramphenicol, 12.4% resistant; and trimethoprim-sulfamethoxazole, 3.8% intermediate, 14.3% resistant. The MICs of penicillin for 66% of the penicillin-nonsusceptible pneumococci were 1-4 microg/ml. Multidrug resistance was found in 64% of penicillin-nonsusceptible and 37% of penicillin-susceptible strains. Sixty-two percent of the penicillin-susceptible, multidrug-resistant strains belonged to serotype 6B and were resistant to all five non-beta-lactam agents tested. This notable serotype 6B resistance pattern was described for the first time in a previous study performed from December 1995 to February 1996 in the city of Patras, southwestern Greece. Seventy-two percent of antibiotic-resistant isolates belonged to serotypes 6B, 9V, 14, 18C, 19F and 23F. These results document the spread of resistant pneumococcal strains in central and southern Greece, many of which are multidrug resistant.

Resistance patterns of streptococcus pneumoniae from carriers attending day-care centers in southwestern Greece.

The resistance to beta-lactam and non-beta-lactam antibiotics of 133 nasopharyngeal isolates of Streptococcus pneumoniae recovered from December 1995 to February 1996 from children attending seven day-care centers in southwestern Greece was studied. Reduced susceptibility to one or more anti-microbial agents was found in 70 isolates (53%), as follows: penicillin, 17% intermediate, 12% resistant; cefotaxime, 10.5% intermediate, 1.5% resistant; trimethoprim-sulfamethoxazole, 8% intermediate, 35% resistant; chloramphenicol, 27% resistant; tetracycline, 29% resistant; and erythromycin/clindamycin, 19% resistant. Eighty-seven percent of penicillin-intermediate or -resistant strains belonged to serogroups/serotypes 19, 21, and 23. Fifty-six percent of the antibiotic-resistant pneumococci were multiply resistant, including serogroup 6 strains that were penicillin-susceptible but resistant to all non-beta-lactam drugs tested, as well as serogroup 23 strains resistant to penicillin, chloramphenicol, tetracycline, and trimethoprim-sulfamethoxazole. The high incidence of antibiotic-resistant pneumococci and the divergent and unique resistance patterns found in this study underline the need for global surveillance of S. pneumoniae to document the evolution and spread of resistant strains and to guide therapy.