Nasal carriage of <i>Staphylococcus aureus</i> has been identified as a risk factor for the development of staphylococcal infections caused by endogenous colonizing strains. Information on the genotypic di...Nasal carriage of <i>Staphylococcus aureus</i> has been identified as a risk factor for the development of staphylococcal infections caused by endogenous colonizing strains. Information on the genotypic diversity of <i>Staphylococcus aureus</i> is relevant for managing epidemiological and clinical challenges resulting from the evolutionary differences of this bacterium. The objective of this study was to determine and compare the molecular diversity of <i>Staphylococcus aureus</i> isolates from three high-risk populations in Yaounde, Cameroon. Molecular analysis confirmed that 95% of 100 tested isolates were <i>S. aureus</i>. The <i>mec</i>A and Panton Valentine-Leukocidin (PVL) genes (<i>lukS/F-PV</i>) were detected in 37% (35/95) and 43% (41/95) of isolates respectively and 18% (17/95) of the isolates harboured both the <i>mec</i>A and <i>lukS/F-PV</i> genes. A mixed distribution of both methicillin sensitive <i>S. aureus</i> (MSSA)/PVL and methicillin resistant <i>S. aureus</i> (MRSA)/PVL strains were detected within the study population. Community associated MRSA accounted for 94% (33/35) of the isolates, further classified into allotypes SCC<i>mec</i> type IV 54% (19/35) and SCC<i>mec</i> type V 40% (14/35), while two isolates were hospital associated SCC<i>mec</i> type II strains. A majority of the isolates harboured a single aggressive gene regulator allele <i>agr</i> type I. Pulsed Field Gel Electrophoresis (PFGE) generated 18 pulsotypes that grouped isolates irrespective of the study population. Multilocus Sequence Typing (MLST) of 12 selected isolates was assigned to six pandemic clonal complexes (CC): CC5 (ST5), CC8 [ST8, (n = 3)], CC15 (ST 15), CC25 (ST 25), CC72 [ST72 (n = 2)] and CC121 [ST 121 (n = 2)] and three atypical sequence types ST 508, ST 699 (CC45) and ST 1289 (CC 88). The study population represents an important reservoir for MRSA, MRSA-PVL and MSSA-PVL which could serve as focal point for further dissemination bringing about significant clinical and epidemiological implications. The predominance of SCC<i>mec</i> IV and <i>agr</i> types in this setting warrants further investigation. Isolates were genetically diverse with MLST indicating that pandemic ST8 was predominant. Detection of atypical STs has provided an insight into the necessity for constant monitoring.展开更多
Gastric colonization by Helicobacter pylori increases the risk of gastric disorders, including atrophic gastritis which can be diagnosed based on levels of serum biomarkers like Gastrin and Pepsinogen. We therefore ex...Gastric colonization by Helicobacter pylori increases the risk of gastric disorders, including atrophic gastritis which can be diagnosed based on levels of serum biomarkers like Gastrin and Pepsinogen. We therefore examined the efficacy of a serological-based method namely GastroPanel Blood kit, in diagnosing and scoring gastritis associated to Helicobacter pylori infection. Patients with dyspeptic symptoms were prospectively recruited on voluntary basis at the Yaounde Central Hospital and University Teaching Hospital, from March to July 2011. The degree of atrophy was classified according to levels in patient serum of pepsinogens I and II (PGI and PGII) and Gastrin 17 (G17) and compared with histological profiles as reference method. A specific ELISA test was used for the detection of H. pylori IgG antibodies. In total, 86 volunteers from 21 to 83 years old (mean = 46.4 ± 3.3) were enrolled, including 74.4% of women and 25.6% of men. The prevalence of gastritis was statistically similar between Gastro Blood Panel test and histology used as reference method (89.5% versus 83.7%: p > 0.20). Diagnosis based on serum makers showed high sensitivity (93.1%) in comparison with the reference method. However, the serological based method has diagnosed more atrophic gastritis than the reference (17.4% versus 7.0%: p 0.05). Furthermore, the prevalence of H. pylori infection did not differ significantly between serological method (84.9%) and reference method (81.4%). These results suggest that diagnosis of atrophic gastritis and H. pylori infection obtained with an optional serological method (GastroPanel) is in a strong agreement with the biopsy findings, and thus can be a useful non endoscopic assessment of stomach mucosal atrophy in patients with dyspepsia.展开更多
文摘Nasal carriage of <i>Staphylococcus aureus</i> has been identified as a risk factor for the development of staphylococcal infections caused by endogenous colonizing strains. Information on the genotypic diversity of <i>Staphylococcus aureus</i> is relevant for managing epidemiological and clinical challenges resulting from the evolutionary differences of this bacterium. The objective of this study was to determine and compare the molecular diversity of <i>Staphylococcus aureus</i> isolates from three high-risk populations in Yaounde, Cameroon. Molecular analysis confirmed that 95% of 100 tested isolates were <i>S. aureus</i>. The <i>mec</i>A and Panton Valentine-Leukocidin (PVL) genes (<i>lukS/F-PV</i>) were detected in 37% (35/95) and 43% (41/95) of isolates respectively and 18% (17/95) of the isolates harboured both the <i>mec</i>A and <i>lukS/F-PV</i> genes. A mixed distribution of both methicillin sensitive <i>S. aureus</i> (MSSA)/PVL and methicillin resistant <i>S. aureus</i> (MRSA)/PVL strains were detected within the study population. Community associated MRSA accounted for 94% (33/35) of the isolates, further classified into allotypes SCC<i>mec</i> type IV 54% (19/35) and SCC<i>mec</i> type V 40% (14/35), while two isolates were hospital associated SCC<i>mec</i> type II strains. A majority of the isolates harboured a single aggressive gene regulator allele <i>agr</i> type I. Pulsed Field Gel Electrophoresis (PFGE) generated 18 pulsotypes that grouped isolates irrespective of the study population. Multilocus Sequence Typing (MLST) of 12 selected isolates was assigned to six pandemic clonal complexes (CC): CC5 (ST5), CC8 [ST8, (n = 3)], CC15 (ST 15), CC25 (ST 25), CC72 [ST72 (n = 2)] and CC121 [ST 121 (n = 2)] and three atypical sequence types ST 508, ST 699 (CC45) and ST 1289 (CC 88). The study population represents an important reservoir for MRSA, MRSA-PVL and MSSA-PVL which could serve as focal point for further dissemination bringing about significant clinical and epidemiological implications. The predominance of SCC<i>mec</i> IV and <i>agr</i> types in this setting warrants further investigation. Isolates were genetically diverse with MLST indicating that pandemic ST8 was predominant. Detection of atypical STs has provided an insight into the necessity for constant monitoring.
文摘Gastric colonization by Helicobacter pylori increases the risk of gastric disorders, including atrophic gastritis which can be diagnosed based on levels of serum biomarkers like Gastrin and Pepsinogen. We therefore examined the efficacy of a serological-based method namely GastroPanel Blood kit, in diagnosing and scoring gastritis associated to Helicobacter pylori infection. Patients with dyspeptic symptoms were prospectively recruited on voluntary basis at the Yaounde Central Hospital and University Teaching Hospital, from March to July 2011. The degree of atrophy was classified according to levels in patient serum of pepsinogens I and II (PGI and PGII) and Gastrin 17 (G17) and compared with histological profiles as reference method. A specific ELISA test was used for the detection of H. pylori IgG antibodies. In total, 86 volunteers from 21 to 83 years old (mean = 46.4 ± 3.3) were enrolled, including 74.4% of women and 25.6% of men. The prevalence of gastritis was statistically similar between Gastro Blood Panel test and histology used as reference method (89.5% versus 83.7%: p > 0.20). Diagnosis based on serum makers showed high sensitivity (93.1%) in comparison with the reference method. However, the serological based method has diagnosed more atrophic gastritis than the reference (17.4% versus 7.0%: p 0.05). Furthermore, the prevalence of H. pylori infection did not differ significantly between serological method (84.9%) and reference method (81.4%). These results suggest that diagnosis of atrophic gastritis and H. pylori infection obtained with an optional serological method (GastroPanel) is in a strong agreement with the biopsy findings, and thus can be a useful non endoscopic assessment of stomach mucosal atrophy in patients with dyspepsia.
