have a higher risk for bacterial invasion, which can lead to colonization and contamination, hampering the
.
‘A camera that produces blue light to detect the presence of bacteria in the wound, diagnosing wound infections before symptoms arise.’
Risk Factors
for Increased Growth of Bacteria in Wounds
- Venous hypertension (high pressure
in the veins of the legs)
- Trauma
- Arterial insufficiency
- Diabetes mellitus
- Rheumatoid arthritis
Wounds may not heal for prolonged periods for some individuals due to long periods of inflammation, impairment in the remodeling of the matrix and problems with re-epithelialization. Bacterial presence in the wounds can lead to contamination and localized infection which can then become systemic and lead to
septicemia.
The normal human
skin has 10
5 organisms that live on the surface of the skin but do
not cause any infection as they do not penetrate the skin. In open wound infection,
however, there is no skin to penetrate and the organism is free to grow and
multiply.
Progress to Colonization of Bacteria in Wounds
Not all bacteria
that are present in wounds colonize to progress to invasive infections. The
colonization of bacteria depend on:
- Bacterial load - Amount of bacteria that is present in a gram of wound
- Virulence
- Pathogenicity
- Host's immune system
β Hemolytic streptococci cause infection even in small counts and is difficult to detect in the early stages. In the initial stages of colonization, the
bacterial wound infection cannot be easily detected.
Detection mostly
occurs when wound healing takes a long time. Some doctors may identify the
progression of bacterial infection based on the smell
from the wound.
Moreover, the
delay in wound healing can affect the individual's health and their economy due
to additional medical expenditure.
Association of Bacteria and Wound Healing
A certain amount
of bacterial load in the wound leads to an increased production of endotoxin
that leads to prolonged exposure to Il-1, Tumor Necrosis Factor-α and other
pro-inflammatory factors. Though inflammation is normal during wound healing,
when there are excessive inflammatory markers during
wound healing, the process is prolonged.
When there is
an excessive growth of virulent bacteria it can lead to
septicemia and even death.
Clinical Signs of Wound Infection
- Pain
- Exudate
- A distinct unhealthy appearance of the wound
- A bad odor
There may be no
pain associated with wound infection in people with certain disease condition
like ischemia, steroid therapy or even malnutrition.
Blue Light for Detecting Bacteria
Tianhong Dai and colleagues reviewed the effect of
blue light on wound healing and the growth of bacteria.
- Blue light results in photo-activation of intracellular porphyrins which leads to the production of ROS.
- Studies showed that when wounds are exposed to blue light for a period of one hour everyday, there was no detrimental effect shown in the healing process.
Moleculight i:X to Detect Bacteria in Wound Infections
Moleculight i:X
is being tested in a couple of UK hospitals as well as in clinical trials in
Canada. This hand-held camera can be used to detect the
presence of micro-organisms in wounds, even before the onset of symptoms.
The camera needs
to be positioned above the wound and then on pressing a button; blue light is produced which react with compounds on the walls of
the bacteria to produce detectable light that can be visualized on screen.
Ryan Kerstein, who is the Head of the Innovation Group at The British Association
of Plastic, Reconstructive and Aesthetic Surgeons, said "This device would lead to more efficient diagnosis of harmful
bacteria that could be slowing down wound-healing, and lead to faster and more
targeted treatment."
The Moleculight i:X is useful in:
- Visualizing real time presence of
bacteria in wounds
- Provide the bacterial load
- Aid in detection of bacterial load
that could be delaying wound healing
- It can be used to take an image or
video of the amount of bacteria present
Leading Infectious Disease doctor with 30
years experience, Dr. Ram Gopalakrishna had this to say
"the device looks promising" but is
cautious about its effectiveness adding "the large trial to show efficacy of
the device is ongoing and not yet completed".
The device that
is undergoing clinical trials will help in improved detection of bacteria in
wounds and assist doctors in effective wound healing process if the
results are found to be promising.
References :
- Blue Light for Infectious Disease
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3438385/
Source: Medindia
