BACKGROUND: We examined how prolonged antibiotic treatment affected the resistance and mutation frequency of human microflora isolated from intestine (Escherichia coli, enterococci spp.), pharynx (alpha-streptococci) and nostril (coagulase-negative staphylococci, CoNS). METHODS: Samples were collected from patients at the Center of Cystic Fibrosis (n=18) and the haematology ward (n=18) of the University Hospital, Uppsala, Sweden. The individually used amount of antibiotics for 1 year was recorded as the defined daily dose (DDD). Primary health care patients (n=30), with no antibiotic treatment for 1 year before sampling, were used as controls. Three isolates of each bacterium from each patient were examined. Antibiotic susceptibilities were determined by disc diffusion. Mutation frequencies to rifampicin resistance were measured on 30 independent cultures of each bacterial species from each individual by plating on rifampicin agar plates. For alpha-streptococci the mutation frequency to streptomycin resistance was also determined. RESULTS: Isolates from patients with high antibiotic use showed a pronounced shift towards increased resistance and a small but significant increase in the mutation frequency compared with isolates from the controls. For E. coli, enterococci and CoNS the increase in geometric mean mutation frequency in the patient group was 3-, 1.8- and 1.5-fold, respectively (P values 0.0001, 0.016 and 0.012). For alpha-streptococci there was a significant difference in geometric mean mutation frequency between patient and control groups for streptomycin resistance (P=0.024) but not for rifampicin resistance (P=0.74). CONCLUSIONS: High antibiotic use selected for commensals with highly increased resistance and a slight increase in mutation frequency.
BACKGROUND: We examined how prolonged antibiotic treatment affected the resistance and mutation frequency of human microflora isolated from intestine (Escherichia coli, enterococci spp.), pharynx (alpha-streptococci) and nostril (coagulase-negative staphylococci, CoNS). METHODS: Samples were collected from patients at the Center of Cystic Fibrosis (n=18) and the haematology ward (n=18) of the University Hospital, Uppsala, Sweden. The individually used amount of antibiotics for 1 year was recorded as the defined daily dose (DDD). Primary health care patients (n=30), with no antibiotic treatment for 1 year before sampling, were used as controls. Three isolates of each bacterium from each patient were examined. Antibiotic susceptibilities were determined by disc diffusion. Mutation frequencies to rifampicin resistance were measured on 30 independent cultures of each bacterial species from each individual by plating on rifampicin agar plates. For alpha-streptococci the mutation frequency to streptomycin resistance was also determined. RESULTS: Isolates from patients with high antibiotic use showed a pronounced shift towards increased resistance and a small but significant increase in the mutation frequency compared with isolates from the controls. For E. coli, enterococci and CoNS the increase in geometric mean mutation frequency in the patient group was 3-, 1.8- and 1.5-fold, respectively (P values 0.0001, 0.016 and 0.012). For alpha-streptococci there was a significant difference in geometric mean mutation frequency between patient and control groups for streptomycin resistance (P=0.024) but not for rifampicin resistance (P=0.74). CONCLUSIONS: High antibiotic use selected for commensals with highly increased resistance and a slight increase in mutation frequency.
Authors: Caroline E C Goertz; Salvatore Frasca; Gregory A Bohach; Daniel F Cowan; John D Buck; Richard A French; Sylvain De Guise; Jennifer Maratea; Lynn Hinckley; Darla Ewalt; Patrick M Schlievert; Sheila M Karst; Claudia F Deobald; David J St Aubin; J Lawrence Dunn Journal: J Vet Diagn Invest Date: 2011-06-15 Impact factor: 1.279
Authors: Romain Béraud; Louis Huneault; Dave Bernier; Francis Beaudry; Ann Letellier; Jérôme R E del Castillo Journal: Can J Vet Res Date: 2008-07 Impact factor: 1.310
Authors: Roger D Kouyos; C Jessica E Metcalf; Ruthie Birger; Eili Y Klein; Pia Abel zur Wiesch; Peter Ankomah; Nimalan Arinaminpathy; Tiffany L Bogich; Sebastian Bonhoeffer; Charles Brower; Geoffrey Chi-Johnston; Ted Cohen; Troy Day; Bryan Greenhouse; Silvie Huijben; Joshua Metlay; Nicole Mideo; Laura C Pollitt; Andrew F Read; David L Smith; Claire Standley; Nina Wale; Bryan Grenfell Journal: Proc Biol Sci Date: 2014-11-07 Impact factor: 5.349
Authors: Anne Mette Lerbech; Japheth A Opintan; Samuel Oppong Bekoe; Mary-Anne Ahiabu; Britt Pinkowski Tersbøl; Martin Hansen; Kennedy T C Brightson; Samuel Ametepeh; Niels Frimodt-Møller; Bjarne Styrishave Journal: PLoS One Date: 2014-12-02 Impact factor: 3.240