Antibiotics sensitivity

Commonly associated with antibiotic-sensitive bacteria... 

Empiric antibiotic therapy is an appropriate approach to traveler s diarrhea. Eradication of the causal microbe depends on the etiologic agent and its antibiotic sensitivity. Most cases of traveler s diarrhea and other community-acquired infections result from enterotoxigenic (ETEC) or enteropathogenic (EPEC) Escherichia coli. Routine stool cultures do not identify these strains primary empiric antibiotic choices include fluoroquinolones such as ciprofloxacin or levofloxacin. Azithromycin may be a feasible option when fluoroquinolone resistance is encountered. 

The polymicrobic nature of contaminating flora makes the use of wide-spectrum antibiotics mandatory [19, 20], The choice of the drug is frequently empirical because small bowel aspiration and culture are impractical and, if performed, will show with certainty multiple organisms with different antibiotic sensitivity. However, the reason why we need to use wide-spectrum antibiotics lies on a still lacking information we do not know which organisms should be eliminated to achieve the improvement of symptoms [19]. Several antibiotics have been shown to be effective (table 3). However, as can be clearly seen from this table, available data are based very frequently on the... 

Ghoshal U, Ghoshal UC, Ranjan P, Naik SR, Ayyagari A Spectrum and antibiotic sensitivity of bacteria contaminating the upper gut in patients with malabsorption syndrome from the tropic. BMC Gastroenterology 2003,3 9. 

An important principle to be emphasized is that there is no single optimal dose for any given antibiotic. There are too many variables such as host resistance, bacterial virulence, bacterial antibiotic sensitivity and site of infection to allow a single dosage recommendation to cover all situations. While many disease problems can be covered by routine dosage levels, special situations may require marked elevation of dosage or perhaps even allow for a reduced dosage schedule. 

In the more recent Chicago outbreak of Salmonellosis, which has been attributed to milk contaminated with a tetracycline-resistant strain of Salmonella typhimurium. there were two deaths verified as resulting from infections with the resistant strain of Salmonel la in 16 284 confirmed cases. If one pools these cases with those cited in the NRDC petition then the incidence of mortality (0.09%) is similar or than that of persons affected by antibiotic-sensitive Salmone1 la (0.21%) also cited by NRDC. Thus the similarity of risks of human infections with resistant and sensitive strains of SaImone 11a agrees with research data obtained in controlled experiments (Smith 15). 

For 38 outbreaks of confirmed mode or source (Table II), multiply resistant salmonella were involved in 33% of the community based outbreaks, 40% of the nosocomial, and 75% of the outbreaks involving both community and hospital. In addition, it has been estimated that each culture-documented case among human beings may represent as many as 100 undocumented cases (10). Agency participation for these cases was made at the request of the local health officials and therefore the survey was not random. However, the resistant strains displayed a fatality rate 21 times that of antibiotic sensitive strains. O Brien et al. (10) found that characterization of plasmid DNA from antibiotic resistant salmonella suggests extensive commingling of human and animal bacteria. 

When alamethicin is added to a ternary vesicle system comprising PDA, phospholipid, and lipopolysaccharide (LPS), the addition of polymyxin, an LPS-binding antibiotic, sensitizes the vesicles to alamethicin (Katz et al. 2003). Cholesterol-containing PDA liposomes have been used to colorimetrically detect streptolysin O, a cholesterol-dependent pore-forming toxin (Ma and Cheng 2005). 

Choice of one aminoglycoside over another for the treatment of serious infections should be guided both by assessment of the antibiotic sensitivities of the spe-... 

Clavulanic acid is produced by Streptomyces clavuligerus and is structurally related to penicillins. This naturally occurring compound is a specific and irreversible inhibitor of a wide range of bacterial -lactamases and, therefore, can enhance the activity of penicillins and cephalosporins against many resistant organisms. Potassium clavulanate can be administered both orally and perenter-ally in combination with antibiotics sensitive to the action of -lactamases. 

Besides physicochemical methods, the use of microbiological growth-inhibition assays to test meat and milk for the presence of antibiotics residues is popular over a long period of time. These tests use antibiotic-sensitive bacterial reporter strains, such as Bacillus subtilis and Bacillus stearothermophilus var. calidolactis. These bacteria are inoculated under optimal conditions with and without sample. After culturing, results are read from visible inhibition zones or from the color change of the bacterial suspension in agar gels [6]. 

JH Toney, PM Fitzgerald, N Grover-Sharma, SH Olson, WJ May, JG Sundelof, DE Vanderwall, KA Cleary, SK Grant, JK Wu, JW Kozarich, DL Pompliano, GG Hammond. Antibiotic sensitization using biphenyl tetrazoles as potent inhibitors of Bacteroides fragilis metallo-beta-lactamase. Chem Biol 5 185-196, 1998. 

Newly synthesized compounds 22, 23, 25c-e, 26d and 29e were screened in vitro for their antimicrobial activities against Gram positive bacteria Staphylococcus aureus (NCTC-7447), Bacillus cereus (ATCC-14579) and Gram negative bacteria Serratia marcesens (IMRU-70) and Proteus merabitis (NTCC-289) using the paper disk diffusion method for the antibiotic sensitivity technique [60]. The tested compounds were dissolved in N,N-dimclhylformamidc (DMF) to obtain a 1 mg/mL solution. The inhibition zones of microbial growth produced by different compounds were measured in millimeters at the end of an incubation period of 48 h at 28 °C. DMF alone showed no inhibition zone. 

Cremer A (1980) Antibiotic Sensitivity and Assay Tests, 4th edn. Butterworths, London, p 521... 

G. G. Hammond, Chem. Biol, 5, 185 (1998). Antibiotic Sensitization Using Biphenyl Tetrazoles as Potent Inhibitors of Bacteroides fragilis Metallo-P-lactamase. 

If meningococcus is confirmed by the microbiology laboratory and antibiotic sensitivity data suggest the strain is sensitive, the patient s therapy may be streamlined to benzylpenicillin i.v. 2.4 g every 4 hours. However, in practice it may be difficult to persuade the clinician to discontinue the initial therapy if the patient shows signs of improving. 

Briscoe D, Rubowitz A,Assia E. Changing bacterial isolates and antibiotic sensitivities of purulent dacryocystitis. Orbit 2005 24 95-98. 

Adjunctive systemic therapy includes ampicillin, amoxicillin, Augmentin, or cefeclor, 250 mg four times daily depending on the patient s body weight and antibiotic sensitivities. Severe or disseminated infection requires hospitalization and treatment with intramuscular or intravenous antibiotics. 

A diagnostic kit for antibiotic sensitivity will not be widely available at the time that product marketing is launched. 

Reliable antibiotic sensitivity spectra have been obtained by monitoring the inhibition of poly(Phe) synthesis on poly(U)-programmed ribosomes from methanogens representative of the Methanobacteriales, Methanococcales [121] Methanosarcinaceae [121,134] and Methanospirillaceae [134] from sulfur-dependent thermophiles belonging to both the Crenarchaeota S. solfataricus[ 35], D. mobilis, T. tenax[ 26]) and the Euryarchaeota... 

There are several instances, however, in which the correlation between antibiotic sensitivity and possession of the prerequisite elements for antibiotic action is less straightforward. This is exemplified by thiostrepton, monosubstituted and disubstituted 2-deoxystreptamines and a-sarcin. 

---