pyrophosphate and Foot-Diseases

Technetium-99 (99Tc) pyrophosphate bone scanning often identifies patients with osteomyelitis before roentgenographic findings appear. However, recent studies have shown that 99Tc bone scanning often gives false-negative results, especially in neonates. The accuracy of computed tomographic scanning and indium-111 leukocyte scanning for diagnosis of early osteomyelitis has not been established. 99Tc bone scanning often gives false-positive results in patients with other conditions leading to bone injury and repair, such as trauma or recent surgery, further limiting the usefulness of this imaging procedure. Newer imaging techniques have not been adequately evaluated to establish their specificity. Because of their high cost and unproved accuracy, these new imaging procedures should not be routinely applied until their usefulness has been established. Bone biopsy remains the procedure of choice for establishing the diagnosis in patients suspected clinically to have osteomyelitis with negative findings on roentgenography and 99Tc bone scanning. Although Staphylococcus aureus is the leading cause of osteomyelitis, other pathogens cause 30 to 40 percent of cases. Aspiration or biopsy of the involved bone is usually required to choose appropriate antibiotic therapy. Bone biopsy is essential in chronic osteomyelitis, since cultures of sinus drainage are unreliable. Osteomyelitis in diabetics with foot infection and in association with decubitus ulcers presents special problems. Radionuclide scanning often give false-positive results in these patients. Proper diagnosis usually requires careful assessment of clinical and roentgenographic findings. Although bone biopsy seems useful in diagnosing osteomyelitis underlying decubitus ulcers, its role in diabetic patients with foot infections is not established. I do not recommend biopsy of foot bones in diabetic patients, since culture of bone biopsy specimens often give unreliable results in these situations because of contamination with ulcer organisms.

Topics: Acute Disease; Bone and Bones; Chronic Disease; Costs and Cost Analysis; Diabetes Complications; Diagnostic Errors; Diphosphates; Foot Diseases; Humans; Osteomyelitis; Radiography; Radionuclide Imaging; Skin Ulcer; Staphylococcal Infections; Technetium; Technetium Tc 99m Pyrophosphate; Wound Infection

Topics: Adult; Aged; Diphosphates; Diphosphonates; Female; Foot; Foot Diseases; Gallium Radioisotopes; Humans; Indium; Male; Middle Aged; Organometallic Compounds; Oxyquinoline; Radioisotopes; Radionuclide Imaging; Technetium; Technetium Tc 99m Aggregated Albumin; Technetium Tc 99m Medronate; Technetium Tc 99m Pyrophosphate; Thallium

We have developed criteria for radionuclide angiography to assess skin ulcer perfusion as an indicator of healing capacity. Twenty-six studies were performed on 21 consecutive patients with nonhealing ulcers of the lower leg; 20 mCi of technetium-99m phosphate was injected intravenously with immediate sequential scintillation camera imaging of the ulcer and surrounding area at 2 second intervals, followed by blood pool and delayed static images. Two radiologists without clinical bias graded the perfusion to the ulcer on the images as normal, increased, or reduced with respect to the opposite limb. Patients were either followed as outpatients for more than 10 days, as inpatients for at least 10 days, or both to determine whether ulcers showed clinical evidence of wound healing with optimal outpatient and in-hospital care. Of the 17 patients whose ulcers healed, imaging with technetium-99m phosphate predicted the outcome in 16. In nine patients the ulcers did not heal. This was correctly predicted by technetium-99m phosphate in eight of the patients. Overall, the sensitivity was 94 percent and the specificity was 89 percent. This technique appears to be a simple, reliable way to predict the microcirculatory adequacy for ulcer healing.

Topics: Diphosphates; Foot; Foot Diseases; Humans; Microcirculation; Prognosis; Radionuclide Imaging; Skin Ulcer; Technetium; Technetium Tc 99m Pyrophosphate; Varicose Ulcer; Wound Healing

Topics: Diphosphates; Foot Diseases; Frostbite; Hand; Humans; Radionuclide Imaging; Technetium; Time Factors