Aug-09

Online Poll Examines Vascular Workup For Patients With Diabetes

By Lauren Grant, Editorial Assistant

   Slightly more than one-third of podiatrists surveyed in a recent online poll said they refer 10 to 20 percent of their patients with diabetes for further vascular workup.

   The poll on PodiatryToday.com posed the question, “What percent of your patients with diabetes do you refer for further vascular workup?” Out of 126 total respondents, 45 DPMs (36 percent) refer 10 to 20 percent of patients with diabetes to vascular specialists. Thirty podiatrists (24 percent) refer 21 to 40 percent of diabetes patients to the vascular team. Only 10 percent of the survey respondents refer more than 80 percent of their patients with diabetes for further vascular testing.

   The poll results did not surprise Alexander Reyzelman, DPM, FACFAS.

    “For the majority of our diabetic patients we treat, the vascular workup can be performed by podiatrists in the office,” notes Dr. Reyzelman, who is an Associate Professor and the Chairman of the Department of Medicine at the California School of Podiatric Medicine at Samuel Merritt University.

   Andrew Rice, DPM, FACFAS, notes that he will perform non-invasive studies in the office but his patient results tend to indicate the need for referral to a vascular specialist.

    “My referrals average in the 41 to 60 percent range with the true number closer to 50 to 60 percent,” says Dr. Rice, who has been in private practice for 22 years in Norwalk, Ct.

   Both doctors cite key findings from non-invasive vascular testing and the clinical exam that would trigger a referral for further vascular work-up.

    “I look for toe pressures of less than 40 mmHg and a toe-brachial index (TBI) of less than 0.4 or an ankle-brachial index (ABI) of less than 0.5 before I refer the patient to the vascular surgeon,” points out Dr. Reyzelman. “My philosophy is to refer the patient who will need to be revascularized. The patient should either have an ischemic non-healing wound, gangrene or disabling intermittent claudication.”

   In addition to absent or diminished pedal pulses, the presence of a non-healing wound and/or an ABI of 0.75 or less, Dr. Rice says pulse volume recordings (PVR) and waveform analysis can reveal the absence of the dicrotic notch in early vascular disease.

    “Occlusions will show a decreased slope of the ascending and descending segments and rounding of the systolic peak, and flattened waveforms,” notes Dr. Rice, a Clinical Instructor in the Department of Orthopaedics and Rehabilitation at the Yale University School of Medicine.

   Both physicians note the critical importance of appropriate vascular testing in this high-risk patient population.

    “Early recognition of limb-threatening ischemia can be the deciding factor in saving or losing part or all of the foot,” maintains Dr. Reyzelman.

   Dr. Rice says these patients would benefit from receiving care from a multidisciplinary team lead by a DPM and vascular specialist. Dr. Reyzelman adds that he would like to see more collaboration between the two specialties at conferences.“I would like to see more forums where vascular and podiatry are presenting and sharing information,” suggests Dr. Reyzelman.

Could Ultrasound Of The Fifth MPJ Help Diagnose RA Earlier?

By Brian McCurdy, Senior Editor

   A recent study in Arthritis Care and Research suggests that targeted ultrasound imaging of the fifth metatarsophalangeal joint (MPJ) may facilitate an earlier diagnosis of rheumatoid arthritis (RA) than radiographs.

   The study involved 30 patients, 17 of whom had RA and 13 of whom had undifferentiated arthritis (UA). Patients underwent lab tests, radiographs and ultrasound imaging of both fifth MPJs.

   Of the 30 patients, researchers noted 10 had ultrasound evidence of synovitis associated with a positive power Doppler signal. Seven had radiographic erosions of the fifth MPJ while ultrasound uncovered evidence of fifth MPJ erosions in 17 patients, according to the study. In addition, authors noted that a positive power Doppler signal was present in nine RA patients and in one UA patient.

   The study researchers note that the radiographic erosion in patients with RA is a late indicator of poor prognosis. However, the study authors note that earlier detection of erosion may permit a more timely initiation of disease-modifying antirheumatic drug (DMARD) therapy, especially in patients with undifferentiated synovitis.

   The study authors conclude that targeted ultrasound provides “rapid and useful” diagnosis of early inflammatory arthritis. In comparison to lab tests, ultrasound is a better indicator of the severity of the disease and patient prognosis, even in the absence of definitive diagnosis, according to the study.

Exploring The Pros And Cons Of Ultrasound

   Nathan Wei, MD, notes that power Doppler ultrasound is “an excellent method for assessing inflammatory changes in the small joints.” He notes that the study results are what one would expect, namely that the technology is sensitive but not very specific.

   Ultrasound is an operator-dependent modality, notes Dr. Wei, a Fellow of the American College of Rheumatology. The better the ultrasonographer, the better the data, posits Dr. Wei.

   Thomas Lyons, DPM, concurs. While he says ultrasound is an effective tool, Dr. Lyons says there is a learning curve and it typically requires a lot of experience in a high-volume musculoskeletal center.

   As Dr. Wei notes, the gold standard for diagnosing RA is magnetic resonance imaging (MRI) with gadolinium. However, he says negative readings are expensive and one needs to find a good musculoskeletal radiologist to read the data.

   Dr. Lyons notes that ultrasound has advantages over MRI in terms of speed and cost. However, using MRI with gadolinium is more advantageous in centers with lower volume and where one has little or no experience in ultrasound diagnosis of synovitis, explains Dr. Lyons, who is affiliated with the Beth Israel Deaconess Medical Center in Boston. He emphasizes that MRI is “excellent” in assessing synovitis.

A1c Assay: The New Standard For Diagnosing Diabetes?

By Brian McCurdy, Senior Editor

   A recent report in Diabetes Care from the International Expert Committee advocates using the A1c assay to diagnose diabetes, citing the assay’s advantages over traditional glucose measurement.

   Authors say A1c “provides a reliable measure of chronic glycemia and correlates well with the risk of long-term diabetes complications.” They note an A1c level of > 6.5% indicates diabetes. One should confirm the diagnosis with a second A1c test unless the patient has clinical symptoms and glucose levels >200 mg/dl. Furthermore, the committee says a measure that captures chronic glucose exposure is more likely to indicate diabetes than a single measure of glucose.

   However, there are a few caveats to using A1c. If one cannot use A1c due to patient factors (hemoglobinopathy or abnormal erythrocyte turnover) that preclude the assay’s interpretation, the committee recommends using diagnostic measures such as fasting plasma glucose (FPG) and 2-h plasma glucose (2HPG).

   The expert committee notes that in children and adolescents, A1c testing is indicated when one suspects diabetes in the absence of classical symptoms or when a plasma glucose concentration is >200 mg/dl. Since diagnosing diabetes in pregnant women can be problematic due to changes in red cell turnover, one should continue using glucose measurements, according to the authors of the Diabetes Care report.

   David Armstrong, DPM, PhD, feels that using A1c may mean that physicians will have a more accurate measure of patients’ long-term control of glucose. If more people get an A1c test, all physicians — including podiatrists — will have better knowledge of the patient’s possible diabetes status, says Dr. Armstrong, a Professor of Surgery and Director of the Southern Arizona Limb Salvage Alliance (SALSA) at the University of Arizona College of Medicine.

   Lawrence Lavery, DPM, notes the A1c test can simplify diagnosis and assessment of diabetes. Many podiatrists are not familiar with the diagnostic guidelines of the American Diabetes Association and World Health Organization, notes Dr. Lavery, a Professor in the Department of Surgery at the Texas A&M Health Science Center College of Medicine.

In Brief

   PathoLase recently announced that it has begun a multicenter trial to assess the use of its PinPointe FootLaser for the treatment of onychomycosis. Study investigators include Richard Pollak, DPM, and Aditya Gupta, MD, PhD.