Propolis exhibits antimicrobial, anti-inflammatory and other biological effects. The aim of this study was to evaluate the activity of 30 % ethanolic extract of Bulgarian propolis against 94 Helicobacter pylori strains by three methods. By the agar-well diffusion method, only 13 . 8 % of the strains exhibited no inhibition by 30 ìl propolis extract (containing 9 mg propolis) and all isolates were inhibited to some extent by 90 ìl of the extract (27 mg propolis) per well. The mean diameters of growth inhibition by 30, 60 or 90 ìl propolis extract or 30 ìl 96 % ethanol per well were 16 . 8, 19 . 2, 27 . 5 and 8 . 3 mm, respectively. The propolis extract was more active than the ethanol (P , 0 . 001). With 90 ìl propolis extract per well, 69 . 4 % of the strains exhibited large diameters of growth inhibition (>20 mm) versus 26 . 6 % with 30 ìl per well (P , 0 . 001). With moist propolis discs, inhibition was detected in more strains (92 . 1 %) than with dried discs (78 . 2 %, P , 0 . 05), with mean inhibitory diameters of 18 . 7 and 13 . 8 mm, respectively. By the agar dilution method, 100 and 300 ìg propolis ml À1 inhibited the growth of 57 . 1 % and 76 . 2 %, respectively, of the 21 strains tested. In conclusion, Bulgarian propolis had a strong and dose-dependent activity against most of the H. pylori strains tested. Although the effect of propolis on H. pylori in vitro is promising, further microbiological, pharmacological and clinical trials are required.

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The aim of this study was to evaluate the primary, combined and post-treatment antibacterial resistance rates in 1205 Helicobacter pylori strains from non-treated (786 adults, 282 children) and treated (109 adults, 28 children) patients in Bulgaria. Susceptibility was tested by the limited agar dilution method. Overall primary resistance rates to metronidazole, clarithromycin, amoxicillin, tetracycline and both metronidazole and clarithromycin were respectively 15?0, 12?5, 1?5, 3?4 and 4?7 % in children and 25?6, 12?6, 0?8, 5?2 and 4?9 % in adults. Primary metronidazole resistance in adults was more common than in children, but the differences for other agents tested were not significant. Primary resistance rates were in the range of those reported worldwide. There was no significant increase in primary resistance rates from 1996/1999 to 2003/2004; however, clarithromycin resistance rates exhibited a slight tendency to increase. Post-treatment resistance to amoxicillin was detected in 1?6 % of 63 strains. Post-treatment resistance to metronidazole was common (81?6 %) and that to clarithromycin was considerable (36 %). Alarming emergence of strains with triple resistance to amoxicillin, metronidazole and clarithromycin was found in two non-treated and three treated patients. The results motivate a larger and continuing surveillance of H. pylori resistance in Bulgaria and worldwide.

Bee glue (propolis) possesses antimicrobial, anti-inflammatory, anaesthetic and immunostimulating activities. The aim of the study was to evaluate the inhibitory effect of Bulgarian propolis on Helicobacter pylori growth in vitro. Activity of 30 % ethanolic extract of propolis (EEP) against 38 clinical isolates of H. pylori was evaluated by using the agar-well diffusion method. Ethanol was used as a control. In addition, the effect of propolis on the growth of 26 H. pylori and 18 Campylobacter strains was tested by the disc diffusion method. Mean diameters of H. pylori growth inhibition by the agar-well diffusion method, using 30, 60 or 90 ìl EEP or 30 ìl ethanol per well, were 17·8, 21·2, 28·2 and 8·5 mm, respectively. EEP was significantly more active than ethanol against H. pylori (P , 0·001). The results obtained by the disc diffusion method were similar. The use of moist propolis discs resulted in mean diameters of growth inhibition of 21·4 mm for H. pylori and 13·6 mm for Campylobacter spp. Dried propolis discs exhibited antibacterial effect against 73·1 % of H. pylori isolates, with a considerable zone of growth inhibition (> 15 mm) in 36·4 % of isolates. Using dried propolis discs resulted in mean diameters of growth inhibition of 12·4 mm for H. pylori and 11·6 mm for Campylobacter spp. In conclusion, Bulgarian propolis possesses considerable antibacterial activity against H. pylori, and can also inhibit the growth of Campylobacter jejuni and Campylobacter coli. The potential of propolis in the prevention or treatment of H. pylori infection is worth further extensive evaluation.

The aim of this study was to assess the primary and combined resistances of Helicobacter pylori isolates obtained from paediatric patients in 2000-2001 to seven antimicrobial agents. Resistance rates of pre-treatment isolates from 115 children were investigated by the limited agar dilution method alone and by the E-test. The cut-off concentrations for resistance were: metronidazole >8 mg/L, clarithromycin and azithromycin >1 mg/L, clindamycin >4 mg/L, amoxicillin >0.5 mg/L, tetracycline >4 mg/L and ciprofloxacin >1 mg/L. Primary resistance rates were: metronidazole 15.8%, clarithromycin 12.4%, azithromycin 14.6%, clindamycin 20.0%, amoxicillin 0%, metronidazole + clarithromycin 4.5%, ciprofloxacin 6.0%, metronidazole + clarithromycin + ciprofloxacin 1.2%, tetracycline 3.1% and metronidazole + ciprofloxacin 1.2%. There were no significant age (1-9 years versus 10-18 years) or gender differences. Prevalence of both macrolideresistant and intermediately susceptible strains was 21.9% for azithromycin and 15.9% for clarithromycin. Of 18 metronidazole-resistant isolates, 77.8% exhibited a metronidazole MIC >32 mg/L. H. pylori resistance rates to metronidazole, clarithromycin and both agents were relatively low in Bulgarian children. However, resistance was found to all drugs tested except for amoxicillin. The consumption of newer macrolides and tetracyclines could be related to the prevalence of resistance to the corresponding agents. There were no significant differences in primary resistance rates of H. pylori to antimicrobial agents between children and adults except for metronidazole. Multi-drug resistance to newer macrolides, metronidazole and ciprofloxacin in association with a slightly elevated amoxicillin MIC (0.38 mg/L) was detected in one strain.

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Helicobacter pylori infection causes chronic gastritis that can trigger peptic ulcer disease and gastric malignancy (Marshall, 1994). The serious complications of peptic ulcers (bleeding or perforation) affect many elderly patients worldwide (Pilotto, 2001). Successful eradication of the infection results in ulcer healing (Adamek et al., 1998) and may prevent the progression of intestinal metaplasia in elderly patients (Pilotto & Malfertheiner, 2002); however, clinical interest in H. pylori infection in elderly people remains low (Pilotto & Salles, 2002). Furthermore, gastroduodenal diseases are associated with other diseases in many old patients. The aim of this study was to evaluate the prevalence of H. pylori infection and primary H. pylori resistance to antimicrobial agents in elderly Bulgarian patients with gastroduodenal diseases.