Antimicrobial susceptibility testing of Helicobacter pylori to selected agents by agar dilution method in Shiraz-Iran.

PURPOSE: To assess the pattern of antimicrobial susceptibility profile of Helicobacter pylori isolates from patients with gastritis, duodenal ulcer (DU) and gastroesophageal reflux disease (GERD) residing in Shiraz, Iran. METHODS: One hundred and six H. pylori isolates from patients with gastritis, DU and GERD undergoing endoscopy at our university hospitals and clinics were analysed for their antimicrobial susceptibility to metronidazole, clarithromycin, amoxicillin, co-amoxiclav, tetracycline, ciprofloxacin and furazolidone. The minimum inhibitory concentrations were determined by agar dilution method. RESULTS: Overall H. pylori resistance rate was 72.6% to metronidazole, 9.4% to clarithromycin and furazolidone, 20.8% to amoxicillin and 4.7% to tetracycline and ciprofloxacin. No resistance to co-amoxiclav was detected among H. pylori isolates. No significant differences between antimicrobial resistance and clinical outcome were detected. CONCLUSIONS: With regard to the increasing resistance of H. pylori isolates to various antibiotics, susceptibility testing of H. pylori isolates prior to the treatment of infection must be performed to achieve better eradication and to reduce the risk of selection of H. pylori resistant strains.

Inhibitory activity of garlic (Allium sativum) extract on multidrug-resistant Streptococcus mutans.

Garlic (Allium sativum) extract has been known to have inhibitory activity on various pathogenic bacteria, viruses and fungi. The objective of present investigation was to study in vitro inhibitory activity of garlic extract on multidrug-resistant (MDR) strains of Streptococcus mutans isolated from human carious teeth. Filter sterilized aqueous extract of garlic was prepared and used in the present study. For isolation of S. mutans, extracted human carious teeth were cultured in Todd-Hewit broth and Mitis-Salivarius-Bacitracin agar. S. mutans was characterized by colony morphology, biochemical tests and other conventional bacteriological procedures. Disk sensitivity tests and broth dilution methods were used to determine antibiotic sensitivity profile and inhibitory activity of garlic extract on S. mutans isolated from carious teeth. Of 105 carious teeth tested, 92 (87.6%) isolates of S. mutans were recovered, among which 28 (30.4%) were MDR since they were resistant to four or more antibiotics. The highest rate of resistance was observed for tetracycline (30.4%) and least resistance (0%) to teichoplanin and vancomycin while 22.8% and 23.9% of the isolates were resistant to penicillin and amoxicillin, respectively. Chlorhexidine minimum inhibitory concentration (MIC) for MDR and non-MDR S. mutans varied from 2 to 16 microg ml(-1) and from 0.25 to 1 microg ml(-1), respectively (P<0.05). All isolates, MDR and non-MDR of S. mutans were sensitive to garlic extract with the MIC ranging from 4 to 32 microg ml(-1). Considering in vitro data obtained in the present study, mouthwashes or toothpaste containing optimum concentration of garlic extract could be used for prevention of dental caries.

Detection of Leishmania donovani soluble antigen and antibody in the urine of visceral leishmaniasis patients.

Urine samples from 21 patients with visceral leishmaniasis were examined for the presence of Leishmania donovani soluble antigen and antibody by double counter-current immunoelectrophoresis. 19 samples revealed both antigen and antibody (IgM in 5 and IgG in all samples). 2 urine samples collected 10 and 13 days after Glucantime treatment revealed only antibody (IgG), not soluble antigen.

Application of electroimmunodiffusion and crossed electroimmunodiffusion tests for the diagnosis of visceral leishmaniasis (kala-azar).

Techniques of electroimmunodiffusion (EID) and crossed electroimmunodiffusion (CEID) were applied and compared with the indirect fluorescent antibody (IFA) test for the diagnosis of visceral leishmaniasis. Results obtained by EID on 28 serum samples of proven cases of kala-azar correlated well with IFA. False-positive reactions were encountered by IFA assay among healthy controls and non-kala-azar patients. Using EID technique, species-specific antibody to L. donovani was demonstrated in all sera of kala-azar patients. CEID was less sensitive than EID as a few false-negative results were obtained with this technique. It is concluded that the EID test which is specific, sensitive and more economical could be applied for diagnosis of systemic leishmaniasis.

Immunofluorescence and counter immunoelectrophoresis in the diagnosis of kala-azar.

Techniques of indirect immunofluorescence (IF) and counter current immunoelectrophoresis (CIEP) were employed and compared for the diagnosis of kala-azar among children in Fars Province of Iran. It is suggested that the diagnostic titre for kala-azar by immuno fluorescence is over 1 in 64. In fact a majority of the cases had a titre of more than 1 in 256. CIEP using soluble antigens prepared form the promastigote form of Leishmania donovani, was also applied to sera from patients with systemic leishmaniasis and other diseases. The CIEP test correlated well with the indirect immunofluorescent test. It is therefore suggested that CIEP, which is a rapid and less sophisticated test, can be applied for the diagnosis of kala-azar cases and epidemiological surveys.