The aim of this study was to evaluate the primary and combined resistance of Helicobacter pylori against four antimicrobial agents by a screening agar method (SAM) and a modi®ed disk diffusion method (MDDM) alone and in combination. Pre-treatment H. pylori isolates from 192 consecutive H. pylori-positive patients at three hospitals in So®a were investigated. MDDM was performed with disks containing metronidazole (5 ìg), clarithromycin (15 ìg) or erythromycin (15 ìg), cipro¯oxacin (5 ìg) and tetracycline (30 ìg). Resistance was determined by an inhibitory zone of <16 mm for metronidazole and <30 mm for other agents tested. The cut-off concentrations used to de®ne resistance by SAM were: metronidazole >8 mg=L, clarithromycin >2 mg=L, tetracycline >4 mg=L and cipro¯oxacin >1 mg=L. Primary resistance rates in H. pylori were: metronidazole 28.6%, clarithromycin 9.7%, metronidazole clarithromycin 2.8%, cipro¯oxacin 3.9%, metronidazole ciprofloxacin 2.3%, tetracycline 1.9% and metronidazole tetracycline 1.2%. Among metronidazole-resistant isolates, combined resistance to clarithromycin, cipro¯oxacin and tetracycline was present in 11.4% (5 of 44 strains), 8.3% (3 of 36) and 4.9% (2 of 41), respectively. Two strains exhibited triple resistance to macrolides, metronidazole and either cipro¯oxacin or tetracycline. Three tetracycline-resistant strains were detected in 1999; however, resistance rates to other agents were relatively stable during the 6 years. Primary H. pylori resistance to metronidazole is moderate and resistance to clarithromycin and to cipro¯oxacin is considerable in comparison with results in most other countries. The alarming appearance of strains harbouring combined resistance or multiresistance provides the motivation for continued surveillance of H. pylori at global, national and regional levels.

No abstract

The results from our study suggest that children with GJB2-related deafness show better auditory performance after cochlear implantation than age-matched children with GJB2-nonrelated sensorineural hearing loss.

A B S T R A C TThe aim of this study was to compare the auditory outcome between two groups of patients with bilateral cochlear implantation depending on the time of placement of the second cochlear implant -less and more than one year after the first one. 14 patients with bilateral cochlear implantation were enrolled and they were divided into two groups depending on the time of placement of the second cochlear implant -less and more than one year after the first one. =9,00; p=0,006). In all other tests (LiP, MTP6, MTP12, MSW, MSW-Phonemes, SLS, SLS-Words, GASP) we obtained comparable results in the observed groups. This is the first study that evaluates the auditory outcome after bilateral cochlear implantation in Bulgarian patients depending on the time between two operations -less and more than one year after the first one. The results have shown that both groups made progress and achieved substantial improvement, but we did not find any statistically significant difference in the auditory outcome between these two groups. Additional studies in larger group of patients with bilateral cochlear implants and long-term follow-up period would confirm оr rejected this.

No abstract