High Serum Creatine Kinase Levels Research Articles

Gallium-67 scintigraphy in macrophagic myofasciitis

Objective To evaluate gallium-67 (67Ga) uptake and the value of 67Ga scintigraphy for diagnosis of macrophagic myofasciitis (MMF), a recently identified inflammatory myopathy. Methods Twelve consecutive patients with MMF confirmed by muscle biopsy, 10 with polymyositis, 10 with sarcoidosis, 8 with fibromyalgia, and 10 with lymphoma without muscle symptoms (serving as normal controls for muscle) were included. Patients received 1.8 MBq 67Ga per kg body weight by intravenous injection, and scintigraphy was performed with a 2-head gamma camera. The various views were acquired for the 3 main photopeaks of 67Ga 48 hours after infusion, and were analyzed in 2 blinded experiments by nuclear physicians. A semiquantitative scale was used to compare the uptake of 67Ga in the vascular soft tissue background with that in the muscles or joints of MMF patients, and with that in the normal controls. Results The MMF patients (4 men and 8 women, mean ± SD age 47.8 ± 8.7 years) had chronic myalgia (n = 11; predominantly in the lower limbs), asthenia (n = 10), arthralgia (n = 7), mild muscle weakness (n = 5), and high serum creatine kinase levels (n = 6). All MMF patients had significantly higher levels of 67Ga uptake in the muscle and para-articular areas than that recorded for the soft tissue background and for the controls. Muscle uptake was bilateral, symmetric, and homogeneous, and predominantly localized in the legs. No linear enhancement corresponding to fascias or synovial involvement was observed. In patients with polymyositis, symmetric, but heterogeneous, 67Ga uptake was observed in muscle, but not in the fascia. In patients with sarcoidosis, 67Ga uptake was nodular and heterogeneous in muscle, was not detected in the fascia, and was suggestive of synovial involvement in the joints. The uptake of 67Ga in fibromyalgic patients was similar to that in normal controls and to that in the soft tissue background. Conclusion MMF is a new condition involving characteristic changes that can be detected by deltoid muscle biopsy. It usually manifests as a weakly specific, chronic arthromyalgic syndrome that predominates in the lower limbs. 67Ga scintigraphy is a noninvasive method that may make it easier to differentiate MMF from fibromyalgia and sarcoidosis.

Comparison of the in vitro caffeine-halothane contracture test with the Ca-induced Ca release rate test in patients suspected of having malignant hyperthermia susceptibility.

We compared the results of the in vitro caffeine-halothane contracture test (CHCT) according to the protocols of the North American Malignant Hyperthermia Group (NAMHG) and the European Malignant Hyperthermia Group (EMHG) with the Ca-induced Ca release (CICR) rate test in the same patients with suspected malignant hyperthermia (MH). Five normal controls and 16 patients suspected of having MH susceptibility were studied. Muscle biopsies were usually obtained from the musculus vastus lateralis. Diagnostic cutoff points and procedures for CHCT protocols were as described in the original and renewal versions of NAMHG and EMHGs. The CICR rate test was performed according to the protocol reported by Endo et al. All five normal controls and two patients with abortive MH, two with postoperative hyperthermia, and three with high serum creatine kinase levels were normal in the three tests. Three patients with MH reactions and one patient with a history of masseter spasm were classified as MH positive according to NAMHG criteria and MH susceptible and MH equivocal according to EMHG criteria. There were five cases with discordant results between the CHCT and CICR rate tests. We propose that muscle biopsy for diagnosis of MH susceptibility should combine the CHCT with the CICR rate test, which may identify the defective site of Ca release channels.

Laminin α2-chain gene mutations in two siblings presenting with limb-girdle muscular dystrophy

We report two siblings, an 11-year-old boy and his 7-year-old sister, referred to us with a diagnosis of muscular dystrophy. The boy presented at 22 months with delay in walking. A very high serum creatine kinase (CK) level and a dystrophic muscle biopsy lead to a diagnosis of Duchenne muscular dystrophy prior to the identification of the dystrophin gene. Two years later his sister presented with similar problems. A diagnosis of limb-girdle muscular dystrophy was made when they were shown to have inherited different X-chromosomes and normal expression of dystrophin and all sarcoglycans. Their conditions remained static. Recently a slowing of the peripheral motor nerve conduction velocities and T2-weighted brain magnetic resonance imaging showed increased signal of the white matter, both of which are features of merosin-deficient congenital muscular dystrophy. Immunolabelling using a C-terminal laminin α2 chain antibody showed a reduction in expression, while labelling with another antibody that recognises a 300-kDa fragment showed a very significant reduction. Mutational analysis of the LAMA2 gene showed two mutations: one was a G→C point mutation at position −1 of intron 28 acceptor splicing site. This mutation induced activation of a cryptic splice at nucleotide 4429 of exon 29 and partial skipping of this exon, with conservation of the open reading frame. The other was a nonsense mutation due to a C_T transition at position 5525 of the cDNA sequence (exon 37), resulting in a stop codon. These data confirm that mutations of the LAMA2 gene that do not completely disrupt the production of the protein can give rise to phenotypes considerably milder than classical merosin-deficient congenital muscular dystrophy. Partial laminin α2 deficiency should be considered in the differential diagnosis of limb-girdle muscular dystrophy.

Myopathy Induced by HMG–CoA Reductase Inhibitors in Rabbits: A Pathological, Electrophysiological, and Biochemical Study

A combination of electrophysiological, pathological, and biochemical studies were performed in myopathy induced by 3-hydroxy-3-methylglutaryl–coenzyme A (HMG–CoA) reductase inhibitors. Simvastatin (a lipophilic inhibitor) or pravastatin (a hydrophilic inhibitor) were administered by gavage to rabbits. In Group I (simvastatin-treated group, 50 mg/kg/day for 4 weeks), four rabbits showed muscle necrosis and high serum creatine kinase (CK) levels, and all six rabbits showed electrical myotonia. In Group II (pravastatin-treated group, 100 mg/kg/day for 4 weeks), no rabbit showed either condition. In Group III (pravastatin-treated group, 200 mg/kg/day for 3 weeks plus 300 mg/kg/day for 3 weeks), one rabbit showed muscle necrosis and high serum CK level and two rabbits showed electrical myotonia. The pathological findings were muscle fiber necrosis and degeneration with increased acid phosphatase activity by light microscopy, autophagic vacuoles and mitochondrial swelling, and disruption and hypercontraction of myofibrils by electron microscopy. Ubiquinone content decreased in skeletal muscle by 22 to 36% in Group I, by 18 to 52% in Group II, and by 49 to 72% in Group III. However, mitochondrial enzyme activities of respiratory chain were normal in all groups. These results indicate that myopathy was not induced by a secondary dysfunction of mitochondrial respiration due to low ubiquinone levels.

The phenotype of chromosome 2p-linked limb-girdle muscular dystrophy

This study reports on a detailed clinical, electrophysiological, muscle computed tomography (CT) and laboratory investigation carried out on five families with definite linkage to chromosome 2p. Some clinical and laboratory features were common to most of the patients, such as the very high serum creatine kinase (CK) levels (mean 43.70 times the normal). The onset was most frequently in the late teens or early twenties with weakness and wasting of the pelvic girdle muscles. All patients had normal motor milestones and had not complained of any symptoms of muscle disease in early childhood. The clinical course was variable both between and within some families, but was most often slowly progressive. Some variability in the pattern of muscle involvement between the different families has also been observed.

High serum creatine kinase levels associated with cylindrical spirals at muscle biopsy

High serum creatine kinase levels associated with cylindrical spirals at muscle biopsy

A carrier of Duchenne muscular dystrophy with dilated cardiomyopathy but no skeletal muscle symptom

A 29-year-old female developed dilated cardiomyopathy at 20 years of age but with no muscle symptoms. Her 2-year-old son with Duchenne muscular dystrophy (DMD) had no demonstrable deletion in the dystrophin gene, but all fibers except for 5% ‘revertant’ fibers in a muscle biopsy specimen had no dystrophin. Both skeletal and cardiac muscle biopsy specimens from the mother showed a mosaic distribution of dystrophin-positive and -negative fibers, and so she was diagnosed as being a manifesting carrier of DMD. We conclude that, when one encounters a female patient with idiopathic cardiomyopathy with a high serum creatine kinase level, the suspicion of her being a manifesting DMD carrier should be ruled out.

TRAUMATIC RHABDOMYLOYSIS FROM SEVERE BEATING—EXPERIENCE OF VOLUME DIURESIS IN 200 PATIENTS

Fluid loading with balanced salt solution (BSS) was carried out in 200 patients with extensive soft tissue injuries from severe beatings. Urinary volume and dipstick specific gravity testing were used to monitor renal function with administration of furosemide for persistent oliguria. Acute intrinsic renal failure (AIRF) occurred in 21 patients (10.5%) and five patients died (2.5%); two of hyperkalemia, two of sepsis and one of multiple organ failure. Significantly increased rates of AIRF and death were associated with injury-admission intervals of more than 12 hours, severe metabolic acidosis, low initial hemoglobin, heavy pigmenturia, and high serum creatine kinase (CK) levels. An increased serum creatinine/BUN ratio was noted in four of the five patients who died. An average of 7.5 L fluids was needed in non-AIRF patients to achieve adequate diuresis with a mean positive fluid balance of 4.7 L. No patient without pigmenturia developed AIRF. Balanced salt solution volume diuresis supplemented with furosemide as necessary appears to be safe and effective in preventing AIRF in soft tissue injuries sustained in beatings.

Maternal serum creatine kinase: A possible predictor of tubal pregnancy

Tubal pregnancy remains a clinical challenge in spite of improvements in diagnostic tests and procedures. In a prospective study we evaluated the role of the serum creatine kinase as a possible marker for tubal pregnancy. Three groups of 17 patients each were included in the study: group A, documented tubal pregnancy; group B, spontaneous abortion; and group C, normal pregnancy. Serum was tested for creatine kinase in all of the patients. Creatine kinase level was > 45 IU/L in all patients with tubal pregnancy, significantly higher than the level in patients in either of the two other groups (p < 0.0001). We conclude that a high serum creatine kinase level can be an important diagnostic test in the evaluation of a suspected tubal pregnancy.

MRI-guided biopsy in inflammatory myopathy: Initial results

The purpose of this report is to describe our initial experience with techniques employing magnetic resonance imaging (MRI) to guide the choice of muscle to be biopsied in patients suspected of having inflammatory myopathy. Five patients with a clinical diagnosis of inflammatory myopathy (IM) were studied. Four were imaged prior to biopsy. Four had repeated examinations, either immediately following biopsy or to evaluate disease progression. Use of MRI to localize muscle lesions was associated with abnormal pathologic findings in all cases, including histopathologic demonstration of lymphocyte infiltration in three cases of idiopathic polymyositis; nonspecific myopathic changes were seen in one patient with probable dermatomyositis and in one patient with chronic inflammatory polyneuropathy and high serum creatine kinase levels (>45,000 IU/ml). The precise location of the area sampled by biopsy was visible in only one of four postbiopsy images. MRI shows promise in identifying pathologic muscle in patients suspected of having one of the inflammatory myopathies; however, further refinement of localization techniques may be needed to optimize histopathologic diagnoses.

Discriminant analysis of ribosomal protein synthesis findings in carrier detection of Duchenne muscular dystrophy.

Previous studies have shown that in vitro muscle ribosomal protein synthesis (RPS) by monomeric ribosomes (MR) and total polyribosomes (TPR) and collagen synthesis (CS) are significantly increased (P less than 0.01) in 47 known carriers of Duchenne muscular dystrophy as compared to 60 age-matched controls. However, there was considerable overlap of the distribution of controls and carriers, particularly for monomeric ribosomal protein synthesis and collagen synthesis. To improve detection of carriers we used discriminant analysis utilizing logs of each measurement as superior to a univariate or bivariate scheme. This study considered four groups: proven carriers (30) (group 1), presumptive carriers (female relatives of Duchenne patients with high serum creatine kinase (CK) levels) (32) (group 2), controls greater than or equal to 20 years old (42) (group 3) and controls less than 20 years (36) (group 4). Comparison of groups, Misclassification (%), (see chart). These results suggest that discriminant analysis reduces the misclassification rates as compared with univariate or bivariate analysis and confirm the superiority of RPS measurements as a carrier test for Duchenne muscular dystrophy.

Histochemically demonstrable fibre abnormalities in normal skeletal muscle and in muscle from carriers of Duchenne muscular dystrophy.

Deltoid muscle was removed at motor point biopsy from 10 female relatives of patients with Duchenne muscular dystrophy and from seven others, with no evidence of neuromuscular disease. Transverse cryostat sections of the muscle from each case were stained for reduced diphosphopyridine nucleotide diaphorase and it was found that all contained varying numbers of degenerating type 1 fibres. The percentage of abnormal fibres in the type 1 fibre population was then calculated for each case and it was found that the muscles from the patients with dystrophic relatives contained considerably higher percentages of abnormal fibres, which also showed more severe degeneration, than did the muscles from the normal cases. There was no absolute correlation between serum creatine kinase levels and degree of pathological change, though patients with the most severe changes in their muscles had abnormally high serum creatine kinase levels. It is suggested that histochemical studies could be a useful addition to the present diagnostic tests for the carrier state in Duchenne muscular dystrophy.

Muscular dystrophy in young girls.

Muscular dystrophy occurred in four girls. In only one of these was the syndrome both proximal and with pseudo-hypertrophy, thus clinically resembling the x-linked Duchenne type of the disease. The evidence for a primary dystrophic process existing in the four individuals is based on the laboratory findings of very high serum creatine kinase levels, myopathic E.M.G. appearances and muscle biopsies. However, each case is clinically different (one is proximal with contractures, another limb girdle with facial involvement and the fourth is distal) and worthy of documentation. The recent demonstration of a neurogenic basis for several myopathies previously considered to be dystrophic in nature has not caused us to revise our view that true muscular dystrophy does occur in girls but that the "Duchenne-like" type is rare.