Potential risk of cross-infection by tourniquets: a need for effective control practices in pakistan.

BACKGROUND: Tourniquets used repeatedly on patients for blood sampling are a potential source of nosocomial infections. They harbor numerous microorganisms, including methicillin-resistant Staphylococcus aureus (MRSA). The aim of this study was to investigate tourniquets for the presence of microorganisms and to ascertain the infection control practices of health care workers. METHODS: A cross-sectional study was carried out in 2012 on 100 samples of tourniquets collected from public and private sector hospitals in Karachi, Pakistan. The samples were cultured, and pathogenic microorganisms were identified and tested for methicillin resistance. A questionnaire was administered simultaneously to 100 health care workers who had used the tourniquets. Descriptive data are represented as frequencies and percentages. Ethical considerations were taken into account. RESULTS: The total colonization rate was 51%, with no bacterial growth in 17/40 and 32/60 samples from public and private sector hospitals, respectively. S. aureus was isolated from 12 (42%) private sector hospital samples and 10 (43%) public sector hospital samples. Although MRSA was found in more samples from public than private sector hospitals, the difference was not statistically significant. Nevertheless, 90% of all elastic and 41% of all rubber tourniquets harbored microorganisms (P < 0.001). Although 96% of health care workers agreed that hospital staff and fomites can transmit infection, none identified tourniquets as a potential source. When asked whether tourniquets appeared clean before use, 66% agreed, and only 25% considered that tourniquets should be washed or cleaned before use. CONCLUSIONS: Tourniquets are a potential reservoir and vehicle for the spread of nosocomial infections, including MRSA. Health care workers have inadequate knowledge about infection control procedures and personal hygiene for disinfecting reusable items.

Gated spect myocardial perfusion scintigraphy for identifying septal perfusion artifacts in left bundle branch block.

OBJECTIVE: To determine the role of gated Single Photon Emission Computed Tomography (SPECT) for accurate assessment of myocardial perfusion scintigraphy (MPS) of patients with left bundle branch block (LBBB). DESIGN: Analytical study. PLACE AND DURATION OF STUDY: Punjab Institute of Nuclear Medicine (PINUM), Faisalabad, Pakistan, from June 2002 to April 2003. PATIENTS AND METHODS: MPS data of patients with LBBB was analyzed. Resting gated SPECT MPS was performed after an injection of 740 MBq 99mTc-MIBI in 10 normal and 25 subjects with LBBB (with low probability of coronary artery disease). Visual and quantitative analyses were done on non-gated (NG), end diastolic (ED), end systolic (ES) images. Calculations included septal to lateral wall ratio (SLR), myocardial thickening (MT=% increase in counts during systole) at end systolic phase and myocardial thickening at peak level (% peak MT). RESULTS: Septal hypoperfusion was noted in 19 (76%) patients on NG images and in only 1 (4%) patient on gated SPECT ED images. On NG images of LBBB group, SLR was lower than in controls (0.68+/-0.07 vs. 0.87+/-0.05, p<0.001). SLR of LBBB patients approached to that of control group in gated SPECT ED data (0.86+/-0.06 vs 0.88+/-0.06, p=ns). Myocardial thickening at ES for septum was markedly lower in LBBB group than in controls (21.83%+/-10.86 vs. 66.32%+/-20.15, p<0.001). CONCLUSION: In patients with LBBB, reduced septal thickening results in artifactual septal perfusion defects. Gating the perfusion scintigraphy and reporting perfusion status on end diastolic frames in LBBB patients can eliminate these artifacts.

99mTc-labeled antimicrobial peptide ubiquicidin (29-41) accumulates less in Escherichia coli infection than in Staphlococcus aureus infection.

UNLABELLED: 99mTc-Labeled antimicrobial peptide ubiquicidin, (99m)Tc-UBI (29-41) in a freeze-dried kit, was evaluated as a bacterial infection-seeking agent in Staphlococcus aureus- and Escherichia coli-induced infections. METHODS: Thirty-three rabbits were classified in 3 groups. Biodistribution of (99m)Tc-UBI (29-41) was studied in 3 animals (group I). Uptake of peptide was determined by counting radioactivity in anatomically fitted regions drawn over the liver, kidneys, urinary bladder, and whole body and expressed as the percentage uptake per organ. Experimental thigh muscle infection was induced by injecting 2 x 10(8) colony-forming units of live S. aureus or E. coli bacteria into the right thigh muscle in 20 rabbits (group II). Turpentine oil and formalin-killed S. aureus were used for inducing sterile thigh muscle inflammation in 10 rabbits (group III). On scintigrams, anatomically adjusted regions of interest were drawn over infected/inflamed (target) and noninfected/noninflamed (nontarget) thigh, and accumulation of (99m)Tc-UBI (29-41) at sites of infection/inflammation was expressed as a target-to-nontarget (T/NT) ratio. RESULTS: A biodistribution study of (99m)Tc-UBI (29-41) revealed rapid removal of tracer from the circulation via the kidneys (10.6% +/- 2.1% at 5 min and 5.9% +/- 0.8% at 60 min) with accumulation of the major part in the urinary bladder within the first hour after injection (66.6% +/- 7.2%). A significantly higher (P < 0.05) accumulation of (99m)Tc-UBI (29-41) was seen at sites of S. aureus-infected animals (T/NT ratio, 2.2 +/- 0.5) compared with that of E. coli-infected animals (T/NT ratio, 1.7 +/- 0.4). The maximum tracer accumulation was observed at 60 min after injection followed by a gradual decline. No significant accumulation was noticed in thighs of rabbits injected with either turpentine oil or killed S. aureus with markedly lower T/NT ratios (P < 0.05) compared with that of S. aureus- and E. coli-infected thighs. CONCLUSION: A (99m)Tc-UBI (29-41) freeze-dried kit can be used for differentiating infections with S. aureus and E. coli with significantly higher scintigraphic intensity (P < 0.05) compared with that of sterile inflammatory sites. The optimum time for infection imaging is 60 min after injection. Relatively low (T/NT) ratios were observed in E. coli infections compared with those of the S. aureus group, which may be due to a low virulence of the former; however, other possible reasons may include low affinity of this peptide for E. coli microbial membranes.