Primary resistance to clarithromycin, metronidazole and amoxicillin of Helicobacter pylori isolated from Tunisian patients with peptic ulcers and gastritis: a prospective multicentre study

<p>Abstract</p> <p>Background</p> <p>The frequency of primary resistance to antibiotics in H. pylori isolates is increasing worldwide. In Tunisia, there are limited data regarding the pattern of H. pylori antibiotic primary resistance.</p> <p>Aim</p> <p>To evaluate the primary resistance of H. pylori to clarithromycin, metronidazole and amoxicillin and to detect the mutations involved in clarithromycin resistance.</p> <p>Materials and methods</p> <p>273 strains isolated from adults and children were enrolled. The primary resistance to clarithromycin, metronidazole and amoxicillin was evaluated by means of E-test minimal inhibitory concentration (MIC). The real-time PCR using Scorpion primers was performed in all cases to assess clarithromycin primary resistance and point mutations involved.</p> <p>Results</p> <p>No resistance to amoxicillin was detected. For adults, resistance to clarithromycin and metronidazole was found respectively in 14.6% and 56.8%, and respectively in 18.8% and 25% in children. Overall, the rates of global primary resistance to clarithromycin and metronidazole in Tunisia were respectively determined in 15.4% and 51.3%.</p> <p>By the use of Scorpion PCR, the A2143G was the most frequent point mutation observed (88.1%), followed by the A2142G (11.9%); the A2142C was not found and 18 of 42 patients (42.8%) were infected by both the resistant and the susceptible genotype.</p> <p>The association of clarithromycin resistance with gender was not statistically significant, but metronidazole resistant strains were isolated more frequently in females (67.8%) than in males (32.2%) and the difference was significant. As for gastroduodenal diseases, the difference between strains isolated from patients with peptic ulceration and those with non peptic ulceration was not statistically significant. When about the distribution of resistant strains to clarithromycin and metronidazole between the three Tunisian cities (Tunis, Menzel Bourguiba and Mahdia), the difference was not statistically significant.</p> <p>Conclusion</p> <p>Local data regarding the primary resistance of H. pylori to clarithromycin, metronidazole and amoxicillin and the main genetic mutation involved in clarithromycin resistance in vivo (A2143G) are necessary to prove a clear need for a periodic evaluation of antibiotic consumption and new therapeutic strategies in Tunisia in order to avoid the emergence of resistant strains.</p

Primary central nervous system lymphoma post kidney transplantation: a case report

Introduction: Primary central nervous system (PCNS) posttransplant lymphoproliferative disease (PTLD) is a rare complication of solid organ transplantation and treatment is not yet standardized.Case presentation: Here we report the case of a 54-year-old man who underwent renaltransplantation 22 years ago for end-stage renal disease. He had been on long-term immunosuppressive treatment consisting of orally administered prednisolone 10 mg and then 5 mg daily and orally administered Mycophenolate Mofetil 500 mg twice daily. He presented in January 2019 to emergency with aphasia and then partial seizure. On brain MRI there was an expansive cortical mass in the left temporal lobe with perilesional edema. Biopsy revealed a diffuse large B-cell lymphoma. He was treated with one cycle of Cytarabine with his usual immunosuppressive treatment. In view of his renal allograft, he was not suitable for Methotrexate due to the risk of toxicity. He died on day 15 caused by a sepsis choc secondary to febrile neutropenia.Conclusion: PCNS-PTLD is regarded as one of the most serious posttransplant complications due to its high mortality. Further clinical and experimental investigations are required to develop optimal diagnostic and treatment modalities

Characterization and quality assessment of recycled post-consumption poly(ethylene terephthalate) (PET)

International audienc

Characterization and quality assessment of recycled post-consumption poly(ethylene terephthalate) (PET)

International audienc

A Novel Extended-Spectrum TEM-Type β-Lactamase, TEM-138, from Salmonella enterica Serovar Infantis

A novel natural TEM β-lactamase with extended-spectrum activity, TEM-138, was identified in a ceftazidime-resistant clinical isolate of Salmonella enterica serovar Infantis. Compared to TEM-1, TEM-138 contains the following mutations: E104K, N175I, and G238S. The bla(TEM-138) gene was located on a 50-kb transferable plasmid. Expression studies with Escherichia coli revealed efficient ceftazidimase and cefotaximase activities for TEM-138