1.Are Dropped Bone Grafts Safe to be Re-used? - An Experimental Study Comparing Efficacy of Chlorhexidine, Povidone-Iodine and Alcohol
Mat-Salleh MF ; Sadagatullah AN ; Ibrahim MY ; Abdul-Aziz I ; Wan-Abdullah WA ; Maning N ; Md-Hassan MN ; Ab-Rashid MR
Malaysian Orthopaedic Journal 2021;15(No.2):70-76
Introduction: A dilemma arises when a bone graft or
fracture fragment is accidentally dropped on the operation
theatre floor and becomes contaminated. This study aimed to
determine the efficacy of simple and readily available
antiseptic solutions in disinfecting contaminated bones.
Materials and methods: This experimental study involved
225 bone specimens prepared from discarded bone
fragments during a series of 45 knee and hip arthroplasty
surgeries. The bone fragments were cut into five identical
cubes and were randomly assigned to either control (positive
or negative), or experimental groups (0.5% chlorhexidine,
10% povidone-iodine or 70% alcohol). The control negative
was to determine pre-contamination culture. All bone
specimens, except the control negative group were uniformly
contaminated by dropping on the operation theatre floor.
Subsequently, the dropped bone specimens except for the
control positive group, were disinfected by immersing in a
respective antiseptic solution for 10 minutes, before
transported to the microbiology laboratory for incubation.
Results: The incidence of a positive culture from a dropped
bone fragment was 86.5%. From the 37 specimens sent for
each group, the incidence of positive culture was 5.4% (2
specimens) after being disinfected using chlorhexidine,
67.6% (25 specimens) using povidone-iodine and 81.1% (30
specimens) using alcohol. Simple logistic regression analysis
demonstrated that chlorhexidine was significantly effective
in disinfecting contaminated bones (p-value <0.001, odd
ratio 0.009). Povidone-iodine and alcohol were not
statistically significant (p-value 0.059 and 0.53,
respectively). Organisms identified were Bacillus species
and coagulase negative Staphylococcus. No gram-negative
bacteria were isolated.
Conclusion: A total of 0.5% chlorhexidine is effective and
superior in disinfecting contaminated bones.
2.Development and validation of TaqMan real-time PCR for the detection of Burkholderia pseudomallei isolates from Malaysia
Mohd Ali, M.R ; Foo, P.C. ; Hassan, M. ; Maning, N. ; Hussin, A. ; Syed Ahmad Yunus, S.Z. ; Fauzi, M.H. ; Muhd Besar, A. ; Harun, A. ; Ismail, N. ; Chan, Y.Y.
Tropical Biomedicine 2019;36(2):379-389
Rapid detection of Burkholderia pseudomallei, the etiologic agent of melioidosis,
allows for timely initiation of appropriate treatment and better clinical outcomes. In the
current gold standard, the culture method is time consuming and suffers from low sensitivity.
Meanwhile, previously reported molecular assays are fast and sensitive, but their performance
on isolates from Malaysia, an endemic region of melioidosis is under reported. This study
designed oligonucleotides targeting orf2 of Type III secretion system (TTSS) genes cluster
for the detection of Malaysian B. pseudomallei isolates and evaluated the assay on 95 local
B. pseudomallei strains, 58 other microorganisms and 71 clinical specimens from patients.
The developed assay exclusively detected all tested B. pseudomallei isolates with a detection
limit of 20 fg per reaction (equivalent to ~2.5 copies). Subsequent testing on clinical samples
showed that the assay detected all confirmed specimens with the growth of B. pseudomallei
(n = 10/10). None of the negative specimens had a detectable signal of our TTSS-orf2 assay
(n = 0/61). In conclusion, the present study provides crucial preliminary data for a subsequent
study and should be considered as a potential alternative to current time-consuming culture
method for the detection of B. pseudomallei.