The population of Bifidobacterium spp in faecal samples from breast-fed and formula-fed infants were investigated and developed antibiogram. The common bacterial growth media such as Man Rogos Sharpe (MRS), Brain Heart Infusion (BHI), Luria Bertani (LB) broth and Bifidobacteria agar were evaluated by the enumeration of Bifidobacterium spp. in faecal material. The results demonstrated that the population of Bifidobacterium spp. in the faecal samples of breast-fed infants is numerically high and, low in formula-fed infants. Phylogenetic analysis of the 16S rRNA, (Xylose/Fructose-6-phosphate phosphoketolase) xfp, and RFLP map of Bifidobacteria isolates suggested a presence of possible new and different Bifidobacterium spp. The intensity of the reddish brown colour formed during the f6ppk (Fructose-6-phosphate phosphoketolase) assay confirms the presence of variable Bifidobacteria. The highest recovery and diversity of Bifidobacteria were obtained from Bifidobacteria agar media. Growth in various media resulted in the formation of small (SCV) and big colony variants (BCV). We understand that the various antibiotic minimum inhibitory concentration (MIC) values obtained by applying different media, growth conditions, after bile salt treatment, and at low pH can vary. This study concludes that the variation of microbiological conditions differentiating resistant and susceptible strains is influenced by the test conditions as well.

The objective of this study was to compare the pathogens and susceptibilities of the current automated rule-based technology (RBT) antibiogram with one manually collected through chart review with additional rules applied. This study was a 2-year, retrospective cohort study and included all bacterial cultures within the first 30 days from patients admitted to a single Burn Center. The current RBT antibiogram served as the control and new antibiogram versions were created using additional rules and compared to the control. Six-hundred fifty-seven patients were admitted (61% excluded for lack of cultures). Fifty-nine percent had at least one hospital acquired risk factor with over one-third having recent illicit drug use and one-third having a recent hospitalization. Of the 410 cultures included, 57% were Gram-negative and half were from wound infections. Sensitivities were significantly different when comparing manual and the RBT version after including factors, such as days since admission, presence of hospital acquired risk factors, or previous antibiotic courses. Recommended empiric Gram-negative antibiotics changed from double coverage to a single β-lactam with > 90% susceptibility. The susceptibilities between first and subsequent courses were dramatically different. Before developing an antibiogram or interpreting the output, it is important to consider which automated criteria are utilized, especially for units with extended lengths of stay.

Catheter-associated urinary tract infection (CAUTI) is one of the most common hospital-acquired infections (HAIs). Prolonged hospitalization, invasive devices such as catheters, and irrational use of antimicrobial agents are believed to be the major causes of high rates of HAIs. Infections such as pyelonephritis, urethritis, cystitis, and prostatitis are the main concern in catheterized ICU patients. In these cases, Gram-negative bacteria are the most common. The present study is undertaken to determine the frequency, antibiograms, disease pattern, and risk factors involved in providing an advocacy recommendation to prevent CAUTI. A total of 1078 patients were admitted to the hospital ICU, out of which healthcare-associated infection was reported in 316 patients. CAUTI was reported only in 70 patients. Klebsiella pneumoniae (20%) was the predominant isolate, with Serratia (3%) and Providencia (3%) species as the least common in this study. The present study provides CAUTI incidence rates in a tertiary care hospital in Hail, Saudi Arabia. Furthermore, information on risk factors of CAUTI common causative organism associated, and their antibiogram patterns are also presented. This study provides vital information that can be used to formulate an effective antibiotic stewardship program that can be implemented throughout the kingdom.

The present study aims to evaluate the antibacterial activity of five commercially available essential oils (EOs): Lavender (LEO), Clove (CEO), Oregano (OEO), Eucalyptus (EEO), and Peppermint (PEO) against the most-known MDR Gram-positive and Gram-negative bacteria - Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853) - alone and in various combinations. Gas Chromatography-Mass Spectrometry (GC-MS) analysis established their complex composition. Then, the antibacterial activity was investigated in vitro by diffusimetric antibiogram method, using sterile cellulose discs with Ø 6 mm impregnated with 10 µl of sample and sterile borosilicate glass cylinders loaded with 100 µl of sample; MIC (µg/mL) for each EO was calculated from IZD values (mm) measured after 24 hours. The following EO combinations were evaluated: OEO+CEO, CEO+EEO, CEO+PEO, LEO+EEO, and EEO+PEO. Then, the influence of each dual combination on 3 conventional antibacterial drugs – Neomycin (NEO), Tetracycline (TET), and Bacitracin (BAC) - activity was investigated. The most active EOs against S. aureus and E. coli were LEO and OEO (IZD = 40 mm). They were followed by the CEO and EEO (IZD = 20-27 mm); PEO exhibited the lowest antibacterial activity (IZD = 15-20 mm). EEO alone showed the highest inhibitory activity on P. aeruginosa (IZD = 25-35 mm). It was followed by the CEO, LEO, and EEO (IZD = 7-11 mm), while PEO proved no antibacterial action against it (IZD = 0 mm). Only one synergic action was recorded (OEO+CEO against P. aeruginosa); EEO+PEO revealed partial synergism against S. aureus and CEO+PEO additive behavior against E. coli. Two triple associations with TET showed partial synergism against E. coli, and the other 2 ones (with NEO and TET) evidenced the same behavior against S. aureus; all contained EEO+PEO or CEO+PEO. Most combinations reported indifference. However, numerous cases were of antagonism between constituents included in double and triple combinations, and EOs with the strongest antibacterial activities belong to the highest antagonistic combinations. A consistent statistical analysis supports our results, showing that EOs with moderate antibacterial activities could generate combinations with higher inhibitory effects based on synergistic or additive interactions.