technetium-tc-99m-pyrophosphate and Pain

We aimed to assess the specificity and sensitivity of (99m)technetium pyrophosphate muscle scintigraphy in the diagnostic workup of patients with suspected myopathy. We reviewed the charts of 166 patients; 52% of the subjects had myalgias, 36% had muscle weakness, 45% had an elevated serum creatine kinase (CK), and 49% had an increased C reactive protein (CRP). Scintigraphy was positive in 34 patients (20%). The test was more sensitive in the presence of muscle weakness, elevated CK, or increased CRP. The presence of myalgias did not influence the odds. Sensitivity was 60% in patients with the final diagnosis of polymyositis, dermatomyositis, or inclusion body myositis, and 70% in noninflammatory myopathies. Eight percent had false positive scintigrams. In individuals with biopsy-proven myopathy (51 subjects), the diagnostic sensitivity was 43%, and its specificity was 60%. Low positive and high negative likelihood ratios (5.0 and 0.65, respectively) document an only limited diagnostic efficiency of (99m)Tc-PYP scintigraphy in the evaluation of inflammatory and noninflammatory myopathies and suggest that the test is not helpful in the routine diagnostic workup of muscle complaints, even after a priori selection of patients for CK plus CRP abnormalities.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biomarkers; C-Reactive Protein; Creatine Kinase; Female; Humans; Male; Middle Aged; Muscle Weakness; Muscle, Skeletal; Muscular Diseases; Pain; Polymyositis; Radionuclide Imaging; Sensitivity and Specificity; Technetium Tc 99m Pyrophosphate

A scintigraphic technique employing technetium pyrophosphate uptake was used to identify the area of skeletal muscle damage in the lower leg of four runners 24 h after an ultramarathon footrace (160 km). Most of the race had been run downhill which incorporated an extensive amount of eccentric work. Soreness was diffuse throughout the posterior region of the lower leg. In order to interpret what increased technetium uptake reflects and to express extreme endurance related damages, a biopsy was taken from the 3-D position of abnormal uptake. In addition, intramuscular pressures were determined in the deep posterior compartment. Scintigraphs revealed increased technetium pyrophosphate uptake in the medial portion of the gastrocnemius muscle. For 3698 fibres analysed, 33 fibres (1%) were necrotic, while a few other fibres were either atrophic or irregular shaped. A cluster of necrotic fibres occurred at the fascicular periphery for one subject and fibre type grouping occurred for another. Ultrastructural analysis revealed Z-line streaming near many capillaries and variously altered subsarcolemmal mitochondria including some with paracrystalline inclusions. The majority of the capillaries included thickened and irregular shaped endothelial cells. Intramuscular pressures of the deep posterior compartment were slightly elevated (12-15 mmHg) for three of the four subjects. Increased technetium uptake following extreme endurance running does not just reflect muscle necrosis but also subtle fibre abnormalities. Collectively, these pathological findings are attributed to relative ischaemia occurring during the race and during pre-race training, whereas, intramuscular pressure elevations associated with muscle soreness are attributed to mechanical stress caused by extensive eccentric work during the race.

Topics: Adult; Humans; Male; Microscopy, Electron; Muscles; Necrosis; Pain; Physical Endurance; Physical Exertion; Pressure; Radionuclide Imaging; Running; Technetium Tc 99m Pyrophosphate

To evaluate the patterns of renal images and the diagnostic value as a screening test of the whole-body bone and renal scintigraphy with technetium-99m-methylene diphosphonate (99mTc-MDP) or -pyrophosphate (99mTc-PYP), we performed bone scintigraphy in 6 patients with acute renal failure (ARF) with severe loin pain and patchy renal vasoconstriction on postcontrast renal computed tomography (CT). All 6 patients were young and previously healthy but experienced severe loin pain after track events. Five took analgesics. Postcontrast renal CT showed patchy low-density areas or diffuse enhancement immediately after radiocontrast injection and then patchy wedge-shaped enhancement 24 or 48 h later, which subsequently disappeared 72 h later. On the whole-body bone scintigrams with 99mTc-MDP or 99mTc-PYP before obtaining renal CT, there was no increased uptake of isotope in the soft tissue, and multiple patchy increased accumulations of the isotope in the kidney were observed in 5 patients. In 2 patients, renal scintigraphies with technetium-99m-dimercaptosuccinate showed photon-deficient areas in the same areas of patchy isotope accumulation in the whole-body bone scintigraphies. Whole-body image and renal scintigraphy with bone-seeking agents may be useful as a screening test and in the search for the theoretical evidence of ARF with severe loin pain and patchy renal vasoconstriction.

Topics: Acute Kidney Injury; Adolescent; Adult; Bone and Bones; Female; Humans; Kidney; Male; Pain; Renal Circulation; Technetium Tc 99m Medronate; Technetium Tc 99m Pyrophosphate; Tomography, Emission-Computed; Vasoconstriction

We have studied the occurrence of skeletal muscle uptake of 99mtechnetium pyrophosphate (Tc-PYP), creatine kinase (CK) release and muscle pain in normal subjects after exercise. Five subjects stepped on and off a high bench in such a way that one leg stepped up and the other down. Pain only developed in the muscles used for descending: quadriceps, adductors and gluteal muscles of one leg and the calf muscle of the other. A large rise in plasma CK occurred in four subjects but no increased Tc-PYP muscle uptake was seen in the quadriceps. In the four subjects with high CK effluxes, increased isotope uptake was seen in the thigh adductors used when stepping down; in the two subjects with the largest CK effluxes there was extensive uptake into the gluteal muscles. Muscle pain preceded and was not well correlated with either the magnitude of the enzyme release or the amount and distribution of increased muscle isotope uptake. We conclude that delayed onset muscle pain, the cause of which remains unknown, is a poor indicator of muscle damage as indicated by circulating muscle enzymes and muscle isotope uptake. Tc-PYP uptake by skeletal muscle can provide useful information about the localisation and time course of muscle damage.

Topics: Adult; Creatine Kinase; Diphosphates; Humans; Muscle Contraction; Muscles; Pain; Physical Exertion; Technetium; Technetium Tc 99m Pyrophosphate

Total body Tc-99m pyrophosphate scintigraphy was performed on 11 "ultramarathon" runners to assess the ability of nuclear medicine techniques to evaluate skeletal-muscle injury due to exercise. We found increased muscle radionuclide concentration in 90% of the runners. The pattern of muscle uptake correlated with the regions of maximum pain. The detection of exercise-induced rhabdomyolysis appeared to be best when scintigraphy was performed within 48 hr after the race, and to be almost undetectable after about a week. It was possible to differentiate muscle injury from joint and osseous abnormalities such as bone infarct or stress fracture. Although 77% of the runners had elevated serum creatine kinase MB activity, cardiac scintigraphy showed no evidence of myocardial injury.

Topics: Adult; Athletic Injuries; Creatine Kinase; Diphosphates; Heart; Humans; Male; Middle Aged; Muscles; Pain; Physical Exertion; Radionuclide Imaging; Running; Technetium; Technetium Tc 99m Pyrophosphate