Broad spectrum resistance in Helicobacter pylori isolated from gastric biopsies of patients with dyspepsia in Cameroon and efflux-mediated multiresistance detection in MDR isolates.

BACKGROUND: Antibiotic resistance is a leading cause of treatment failure in Helicobacter pylori infection. In Africa, there are very little data concerning the susceptibility of Helicobacter pylori isolates to antibiotics. The purpose of this study was to evaluate the resistance prevalence of Helicobacter pylori strains circulating in Cameroon, and to assess overexpression of efflux pump as a possible multi-drug resistance mechanisms. METHODS: A total of 140 H. pylori isolates were recovered from gastric biopsies of dyspeptic patients in two reference hospitals in Cameroon and analyzed for their antimicrobial susceptibility to amoxicillin, co-amoxiclav, ampicillin, penicillin, imipenem, metronidazole, rifabutin, erythromycin, clarithromycin, azithromycin, levofloxacin, ciprofloxacin, norfloxacin, tetracycline, doxycycline and minocycline. Antibiotic sensitivity was tested by disk diffusion method. Phe-Arg-naphthylamide (PAßN) was used as efflux pump inhibitor. INT broth microdilution method in supplemented Brain Heart Infusion broth was used to determine the MIC of ampicillin, amoxicillin, metronidazole, erythromycin, clarithromycin and doxycycline in the absence and the presence of PAßN against 32 selected MDR isolates. RESULTS: Overall H. pylori resistance rate was 100% to ampicillin, penicillin and co-amoxiclav; 97.14% to amoxicillin, 97.85% to metronidazole, 47.85% to erythromycin, 13.57% to clarithromycin; 5, 2.86 and 0.71% to doxycycline, tetracycline and minocycline respectively. No resistance to azithromycin, rifabutin, imipenem, ciprofloxacin, norfloxacin and levofloxacin was detected among H. pylori isolates. Seventy percent (70%) of the tested isolates elicited a multiple drugs resistance pattern; 42.57% double, 15.71% triple and 5.71% quadruple drugs resistance. Metronidazole and amoxicillin were more concerned with double resistance pattern (86.76%). The spectrum of activity recorded with metronidazole, doxycycline, clarithromycin and erythromycin ranged from 0 to 100% in the absence to the presence of PAßN against the tested MDR isolates. An 8 to 128-fold increase in potency was also noticed with these antibiotics in the presence of PAßN. CONCLUSION: With regard to the high resistance rate to both amoxicillin and metronidazole, these drugs should be avoided as components of triple therapy in our milieu. In contrast, ciprofloxacin, norfloxacin, levofloxacin and tetracyclines could be used to achieve a better eradication rate and to reduce the risk of selection of H. pylori resistant strains.

Treatment of Helicobacter pylori infected mice with Bryophyllum pinnatum, a medicinal plant with antioxidant and antimicrobial properties, reduces bacterial load.

CONTEXT: Bryophyllum pinnatum (Lam.) Kurz (Crassulaceae) is a plant known for its antiulcer properties. OBJECTIVE: This study evaluates the anti-Helicobacter pylori activity of Bryophyllum pinnutum methanol extract with a mouse model and its antioxidant properties. MATERIALS AND METHODS: Dried leaves of Bryophyllum pinnutum were extracted with methanol and ethyl acetate. Broth microdilution method was used to evaluate the anti-Helicobacter activity of extract samples in vitro. Swiss mice were inoculated with a suspension of Helicobacter pylori and divided into control group and four others that received 125, 250, 500 mg/kg of methanol extract or ciprofloxacin (500 mg/kg), respectively, for 7 days. Helicobacter pylori colonization and bacterial load of mouse stomach was assessed on day 1 and 7 post-treatment. The antioxidant activity of Bryophyllum pinnutum was evaluated through DPPH radical, hydroxyl radical and reducing power assay. RESULTS: Methanol extract showed a significant anti-Helicobacter activity with MIC and MBC values of 32 and 256 µg/mL, respectively. Bryophyllum pinnatum and ciprofloxacin reduced H. pylori colonization of gastric tissue from 100% to 17%. Bryophyllum pinnatum extract (85.91 ± 52.91 CFU) and standard (25.74 ± 16.15 CFU) also reduced significantly (p < 0.05) bacterial load of gastric mucosa as compared to untreated infected mice (11883 ± 1831 CFU). DPPH radical, hydroxyl radical and reducing power assays showed IC50 values of 25.31 ± 0.34, 55.94 ± 0.68 and 11.18 ± 0.74 µg/mL, respectively. DISCUSSION AND CONCLUSION: The data suggest that the methanol extract of Bryophyllum pinnatum could inhibit Helicobacter pylori growth, and may also acts as an antioxidant to protect gastric mucosa against reactive oxygen species.

Anti-Helicobacter pylori and antiulcerogenic activity of Aframomum pruinosum seeds on indomethacin-induced gastric ulcer in rats.

CONTEXT: Peptic ulcer is one of the most common diseases affecting mankind. Although there are many products used for its treatment, most of these products produce severe adverse reactions requiring the search for novel compounds. Some Afromomum species are used traditionally to cure acute gastritis. OBJECTIVE: To evaluate the antiulcer activity of the methanol extract of Aframomum pruinosum Gagnepain (Zingiberaceae) seeds against two major etiologic agents of peptic ulcer disease; Helicobacter pylori and non-steroidal anti-inflammatory drugs. MATERIALS AND METHODS: The anti-Helicobacter activity of A. pruinosum was evaluated using the broth microdilution method. After oral administration of indomethacin (5 mg/kg) for 5 consecutive days, gastric ulcerated animals were divided into control group and five other groups: three groups that recieved respectively 125, 250 and 500 mg/kg of plant extract, the fourth group received Maalox (50 mg/kg) and the fifth group, Misoprostol (100 µg/kg), respectively, for 5 days. Ulcer areas, gastric mucus content and nitric oxide gastric levels of animals were assessed 24 h after this treatment. RESULTS: A. pruinosum extract shows a moderate anti-Helicobacter activity with an MIC value of 128 µg/mL. A. pruinosum extract, like Misoprostol and Maalox, markedly reduces the % of ulcerated area from 8.15 ± 0.33 to 1.71 ± 0.44% (500 mg/kg). It also increased significantly mucus and NO gastric production with respective values of 4.44 ± 1.35 and 965.81 ± 106.74 µmol/g (500 mg/kg). DISCUSSION AND CONCLUSION: These findings suggest that A. pruinosum methanol extract possesses antiulcer properties as ascertained by the comparative decreases in ulcer areas, increase of mucus and NO gastric production.

Relationship between active Helicobacter pylori infection and anemia, iron deficiency, iron deficiency anemia: A cross-sectional study in a sub-Saharan setting.

Background and Aim: There have been contradictory reports about the association between Helicobacter pylori infection and iron deficiency anemia (IDA). Based on the high frequency of H. pylori infection in Cameroon, we have evaluated the frequency of H. pylori infection as the cause of anemia, and IDA among dyspeptic patients in Cameroon. Methods: This cross-sectional study enrolled 842 dyspeptic patients (472 women and 370 men) in two reference hospitals in Douala-Cameroon. Each participant gave a written consent, and the study was approved by the National Ethical Committee. Erythroid-related indices and markers of iron deficiency (ID) measurement were done for each participant as well as H. pylori detection. Data were analyzed using SSPS statistical package. Results: The prevalence of anemia, ID, IDA, and H. pylori infection was 65.08%, 31.47%, 25.65%, and 80.88%, respectively. H. pylori infected individuals had a significantly lower mean value of hemoglobin (P = 0.01), hematocrit (P = 0.04), ferritin (P = 0.03) and coefficient of transferrin saturation (CTS) levels (P = 0.04) and a significantly higher mean value of mean corpuscular hemoglobin concentration (MCHC) (P = 0.02). Compared with H. pylori non-infected participants, H. pylori infected patients were 1.2938 (95% confidence interval [CI]: 0.9087-1.8421), 1.1851 (95% CI: 0.8122-1.7292), and 1.5636 (95% CI: 1.0206-2.3953) times at higher risk to develop anemia, ID, and IDA, respectively. A significant relationship was found between H. pylori infection and IDA (P = 0.04 and 0.04 for crude and age/sex-adjusted, respectively). Conclusion: H. pylori infection seems to be associated with anemia, and IDA among dyspeptic patients in our milieu.

Rate of virological failure and HIV-1 drug resistance among HIV-infected adolescents in routine follow-up on health facilities in Cameroon.

The objective of this study was to determine the rates of virological failure (VF) and HIV drug resistance (HIVDR) amongst adolescents on antiretroviral Therapy (ART). A retrospectively designed study was conducted in 10 healthcare centers for adolescents living with HIV (ALHIV) in the two main cities of Cameroon (Yaoundé and Douala), from November 2018 to May 2019. Sociodemographic, clinical, therapeutic and laboratory parameters were collected from medical records. All enrolled ALHIV had viral load (VL) measurements following the national guidelines. All patients with a VL ≥ 1000 copies/ml were called to perform genotyping tests. The chi-square test was used to determine the factors associated with VF. Out of the 1316 medical records of ALHIV, we included 1083 ALHIV having a VL result. Among them, 276 (25.5%) were experiencing VF, and VF was significantly higher in ALHIV with suboptimal adherence (p<0.001), older adolescents (p<0.05), those who lived outside the city where they were receiving ART (p<0.006), severely immunocompromised (p<0.01) and started ART at infancy (p<0.02). Among the 45/276 (16.3%) participants with an available genotyping resistance testing (GRT) result, the overall rate of HIVDR was 93.3% (42/45). The most common mutations were K103N (n = 21/42, 52.3%) resulting in high-level resistance to Efavirenz and Nevirapine, followed by M184V (n = 20/42, 47.6%) and thymidine analog mutations (n = 15/42, 35.7%) associated with high-level resistance to Lamivudine and Zidovudine respectively. The high rate of VF and HIVDR among ALHIV regularly followed in health facilities in Cameroon highlights the need to develop interventions adapted to an adolescent-centered approach to preserve future ART options.

In Vitro and In Vivo Anti-Helicobacter Activities of Eryngium foetidum (Apiaceae), Bidens pilosa (Asteraceae), and Galinsoga ciliata (Asteraceae) against Helicobacter pylori.

This study was performed to evaluate the antimicrobial activities of extracts of Bidens pilosa, Galinsoga ciliata, and Eryngium foetidum against 6 clinical strains of Helicobacter pylori in vitro and in vivo. Broth microdilution method was used in vitro. In vivo, Swiss mice were inoculated with H. pylori and divided into 5 groups; the control group received the vehicle and the four others received 125, 250, and 500 mg/kg of methanol extract of Eryngium foetidum and ciprofloxacin (500 mg/kg) for 7 days, respectively. Helicobacter pylori colonization and number of colonies in gastric biopsies culture were assessed on days 1 and 7 after treatment. The lowest MIC value (64 µg/mL) and the best spectrum of bactericidal effect (MBC/MIC = 1) were obtained with the methanol extract of Eryngium foetidum. The number of H. pylori infected animals was 17% (plant-extract) and 0% (ciprofloxacin) compared to 100% for the infected untreated group. Plant-extract (381.9 ± 239.5 CFU) and ciprofloxacin (248 ± 153.2 CFU) significantly reduced bacterial load in gastric mucosa compared to untreated, inoculated mice (14350 ± 690 CFU). Conclusion. The present data provided evidence that methanol extract of Eryngium foetidum could be a rich source of metabolites with antimicrobial activity to fight Helicobacter pylori infections.