SAN FRANCISCO -- A $50 off-the-shelf gadget might help improve the treatment of skin and soft tissue infections, a researcher said here.
The device – a laser industrial thermometer – can be used to quantify changes in skin surface temperature that reflect the progress of treatment, according to Michael Montalto, MBBS, of Epworth Hospital in Melbourne, Australia.
"We think outcome measures at the moment aren't particularly good" – such things as absence of fever, extent of erythema, and inflammatory markers, he told MedPage Today at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.
But skin temperature could be a useful surrogate, he said -- if it could be measured easily and accurately.
The only problem was finding a way to carry out the measurements, an obstacle that was resolved when he and colleagues found small handheld industrial thermometers that sold for $90 each in Australia.
"Then," he said, "I found them for $50 at Radio Shack on Market St. (in San Francisco)."
He and colleagues in Australia and New Zealand enrolled 63 patients who had been admitted to hospital for skin infections – most of them on the leg -- and were being treated with intravenous antibiotics. On average, they were in hospital for 4.9 days.
Nurses measured skin temperature on the affected limb and on the corresponding area on the unaffected limb every day and the researchers compared differences on a daily basis.
On average, the day one skin temperature at the hottest spot on the affected limb was 34.4 degrees C, Montalto said, compared with 30.9 on the unaffected limb.
On the last day in hospital, the corresponding temperatures were 32 and 29.9 degrees C.
The differences at both times were significant, but the downward trend in the affected limb -- itself significant -- gave evidence of the effect of treatment, Montalto said. The shallower downward trend in the unaffected limb was not expected, but he said it was probably a reflection of better health systemically.
The only other common sign that was significantly different over time was pulse rate; core body temperature and blood pressure did not vary markedly.
The research is in its early days, Montalto cautioned. In the long run, it's possible that measuring skin temperature might give doctors clues as to the type of microorganism involved and help guide treatment choices.
The approach is "potentially a better way of monitoring (the treatment of) people," commented Tony Korman, MD, an infectious disease specialist at Monash University in Melbourne, who was not part of the research.
"What we don't have," Korman told MedPage Today, "is a good measure of when to stop antibiotics."
Some clinicians resort to drawing lines around the inflamed areas with a marker, so that they can see if infection is spreading or receding, but that approach has not been shown to be very accurate, he said.
He cautioned that the study is a pilot and needs to be replicated in a larger population.
The researchers did not report external support for the study.
Montalto had no relevant financial disclosures.
- Reviewed by Dori F. Zaleznik, MD Associate Clinical Professor of Medicine, Harvard Medical School, Boston and Dorothy Caputo, MA, BSN, RN, Nurse Planner
Interscience Conference on Antimicrobial Agents and ChemotherapySource Reference: Montalto M, et al "Skin surface temperature: An objective measure of severity and treatment response in acute skin and soft tissue infection" ICAAC 2012; Abstract L1-1667.