We examined the case histories of seven pediatric patients (ages four days to 12 years) whose sera showed significant activities of "macro" creatine kinase (CK; EC 2.7.3.2): two cases of macro CK type 1 (CK-BB isoenzyme bound to IgG) and five cases of macro CK type 2 (polymeric complexes of mitochondrial CK). The diagnoses of the two children with macro CK type 1 were similar to those in 55 adult patients with this form of CK found earlier during screening of a population of 5000. Macro CK type 1 has generally been noted only in older women; this is the first report of it in children. In four of the five cases of macro CK type 2 we found in children, myocardial muscle damage was clinically evident. In contrast, the 26 cases of adults with macro CK type 2 found during the same screening generally had neoplasms, most with metastases to the liver. We suggest that the finding of macro CK type 2 is an indicator of cellular necrosis; in pediatric cases with myocardial damage the associated conditions may be reversible but in adults with malignancies the finding is associated with an extremely poor prognosis.

We used an enzyme-linked immunoabsorbent assay to measure creatine kinase (CK; EC 2.7.3.2) BB in the sera of 58 cancer patients. A pre-incubation step with an anti-CK-M antibody-coated bead removed M chain components, and CK-BB was quantified with use of an anti-CK-B antibody-coated tube. No cross reactivity was observed with mitochondrial CK or CK-MM; CK-MB cross reacted slightly (1.6%). Macro CK type 1 was measured as CK-BB. Average analytical recovery of purified CK-BB added to serum was 97.7%. Although the enzyme activity of CK-BB is labile, our studies show that this protein is antigenically stable for 12 months when stored frozen. The upper limit of normal for CK-BB concentration was 0.3 micrograms/L (95th percentile, n = 25). Of the 20 cases of breast cancer of various stages, none showed any increases of serum CK-BB. Only two of 18 patients with prostatic carcinoma (stage D), and two of 10 patients with oat-cell carcinoma of the lung had increased concentrations of CK-BB in the serum. Ten patients with squamous cell cancer of the lung had normal concentration of the enzyme. Thus the CK-BB isoenzyme is not frequently increased in cancers of the prostate, lung, and breast, and it has little apparent value as a tumor marker for these diseases.

The isoenzyme patterns of creatine kinase (CK) and lactate dehydrogenase (LDH) were examined in cultured fibroblasts derived from the gingival tissue of a healthy person and patients with periodontitis and gingival fibromatosis. Human foreskin fibroblasts were also included for comparison. Cytosol fractions were prepared by sonication and centrifugation. Gingival fibroblasts from normal subjects (A), and from patients with periodontitis (B) or fibromatosis (C), exhibited CK-MM (muscle form) as a predominant isoenzyme and CK-BB (brain form) as a minor fraction. There was no significant difference in specific activities of CK-BB fraction in all 3 types of fibroblasts. However, B fibroblasts contained a higher proportion of MM type isoenzyme than A fibroblasts. C fibroblasts showed the lowest amount of CK-MM isoenzyme as compared to either A or B fibroblasts. In contrast, fibroblasts derived from human foreskin (D) contained only a small amount of CK-BB isoenzyme, but CK-MM was not present. In the studies of LDH isoenzymes, A, B, and C fibroblasts possessed only 3 isoenzymes, namely, LDH-3, LDH-4 and LDH-5. In terms of the relative abundance of M vs H subunits, A, B, and C fibroblasts were shown to have a preponderance of M subunits (85-87% M vs 13-15% H subunits). In comparison, D fibroblasts contained 4 isoenzymes (LDH-2, LDH-3, LDH4, LDH-5) with 73% M and 27% H subunits. The ratio of LDH-5 to LDH-4 was calculated for all fibroblasts tested, and the values were 1.11 in A, 1.39 in B, 1.16 in C and 0.64 in D.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum creatine kinase BB (CK-BB) and neuron specific enolase (NSE) were measured with chromatography-fluorometric method and ABC-ELISA in 20 patients with small cell lung cancer (SCLC), 30 patients with non small cell lung cancer (NSCLC), 25 patients with benign pulmonary diseases (BPD) and 30 healthy subjects (C). The results revealed that serum concentrations of CK-BB and NSE in SCLC were significantly greater than those in other three groups (P < 0.001). The mean values of CK-BB and NSE in SCLC, NSCLC, BPD, C were 30.2, 8.4, 6.3, 4.3 IU/L and 52.2, 12.7, 10.3, 9.2 ng/ml, respectively. If values above 9.5 IU/L (CK-BB) and 20.8 ng/ml (NSE) were considered abnormal, 70% and 80% of the values of CK-BB and NSE in SCLC were positive, respectively, which were higher than those in NSCLC (P < 0.005). The serum levels of CK-BB had linear correlation with those of NSE in SCLC (r = 0.7934, P < 0.001). By combined determination, the sensitivity and specificity were increased to 90% and 94% respectively. Therefore, the results suggest that serum CK-BB and NSE be diagnostic markers for SCLC. Concurrent determination may raise their value in clinical use.

We analytically and clinically evaluated Abbott's IMx assay for creatine kinase (CK) isoenzyme MB (CK-MB) in serum. Over a 1-year period, the method was more specific but less precise than catalytic isoenzyme measurements by electrophoresis or immunoinhibition. Sera from different individuals without electrophoretic evidence of CK-MB but containing macro CK type 1 (n = 20), mitochondrial CK (n = 5), or CK-BB (n = 5) were scored as CK-MB negative by the IMx. Likewise, CK-MB-negative by the sera remained so after addition of purified human CK-MM (< or = 7600 U/L) or CK-BB (< or = 8100 U/L). For 39 patients admitted for suspicion of uncomplicated acute myocardial infarction (precordial pain for < or = 4 h), the diagnostic performance of the IMx CK-MB assay on admission and 4 h later was superior to that of total CK activity and compared well with that of CK-MB activity measured by electrophoresis or immunoinhibition. An admission, myoglobin showed a higher diagnostic sensitivity, specificity, and predictive value than did CK-MB and was the most informative test. Diagnostic performance on admission and 4 h later was further improved by considering positivity for myoglobin and for CK-MB by IMx and for the change in each over the first 4 h of hospitalization as criteria. Twelve hours after admission, diagnostic performance was further improved for all CK and CK-MB methods but began to decline for myoglobin.

A 72 year old woman presented with a suspected myocardial infarction. An echocardiograph showed no acute changes but her plasma creatine kinase (CK) activity was increased at 343 U/l (< 175 normal range). The apparent creatine kinase-MB activity by a CK-M subunit immunoinhibition assay was 350 U/l. In view of the discrepancy between the total creatine kinase and CK-MB activity plasma creatine kinase electrophoresis studies were performed which showed not only a band of creatine kinase-MM but also a band of creatine kinase-BB, 53% of the total creatine kinase activity. No band of CK-MB was seen. It later transpired that the woman had myelodysplasia. It is suggested that premalignant and malignant haematological conditions should be considered in patients with an unexplained increase in plasma CK-BB.

A variant creatine kinase (CK) isoenzyme was identified in the sera of some patients who had advanced adenocarcinoma of the breast, stomach, and large intestine. A similar variant isoenzyme, together with a high concentration of CK-BB isoenzyme, was identified in some breast tumor cytosols. The variant creatine kinase activity in both sera and tumor cytosols was unaffected by antibodies specific for both the CK-M and DK-B subunits. This indicates that DK-MB isoenzyme determinations are currently best performed by electrophoretic rather than immunologic technics.

We describe an atypical form of creatine kinase in the serum of a woman after myocardial infarction. Electrophoresis on agarose gel showed a single fraction between CK-MM and CK-MB isoenzymes. After ion-exchange chromatography on DEAE-Sephadex A-50 we isolated the atypical CK and CK-BB as detected by electrophoresis of the eluted fractions. Results of our immunological investigations and exclusion chromatography clearly demonstrate that the atypical CK consists of complexes with high molecular masses formed by CK-BB isoenzyme and immunoglobulin G. The clinical significance, if any, of this Macro CK has yet to be determined.

Muscle cells were cultured from six patients with Duchenne muscular dystrophy and nine normal subjects. Protein and myosin content and pyruvate kinase (PK) activity were similar in normal and Duchenne muscular dystrophy cultures. Creatine kinase (CK) activity was lower in Duchenne muscular dystrophy cultures and the isoenzyme distribution indicated MB-CK was significantly lower, while BB-CK was significantly higher in later Duchenne muscular dystrophy cultures. This abnormal isoenzyme pattern suggested aberrant or impaired maturation of Duchenne muscular dystrophy myotubes in vitro.

The activity and isoenzyme spectrum of creatine kinase (CK) were studied in cytosole fraction 60 of the mammary gland carcinoma (MGC) and in the corresponding unchanged tissues. The values of the CK activity in MGC were found to be highly different (0.05-14.6 unit/g of tissue). The correlation of CK activity in MGC with the menstrual function was revealed. Enhancement in the CK activity is due to an increase in the BB-isoenzyme activity and an appearance of atypical supplementary MM1-isoenzyme is, possibly, of mitochondrial origin. These isoenzymes may be nonspecific markers of malignancy and may be used for diagnosis of mammary gland carcinoma.

A considerable interest has recently been shown for the measurement of isoenzyme BB of creatine kinase as a diagnostic and prognostic indicator of tumor growth. This isoenzyme belongs to the group of oncofetal antigens and in human cancer elevated levels occur frequently in patients with metastatic disease. In this study we have attempted to quantify CK-BB serum levels during the growth of an experimental tumor (Yoshida Hepatoma AH 130) in male albino rats to determine if a significant correlation exists between isoenzyme serum levels and the rate of tumor growth. Creatine kinase-BB was measured spectrophotometrically by immunoinhibition of creatine kinase-M subunits. CK-BB normal values were 4.19 +/- 0.4 U/L and between days 5 and 9, where there is an increase in the rate of proliferation of neoplastic cells, CK-BB serum levels reaches its maximum 69.01 +/- 2.2 U/L. These data are in agreement with the hypothesis that the highest isoenzyme levels are a measure of the aggressiveness of the neoplastic clone. Moreover, this hypothesis is consistent with the proposed mathematical model, and we plan to expand this line of study to evaluate the predictive potential of this tumor marker in man.

The present study demonstrates a change occurring in the creatine-kinase isoenzyme profile of cardiomyocyte cultures induced by a chronic administration of excessive amounts of thyroid hormones (TH). This change is manifested by an increased level of the CK-BB isoenzyme, generally at the expense of CK-MM isoenzyme. The elevation of CK-BB is probably a result of a specific effect of TH through activation of gene expression, rather than a contribution of an increased number of non-myocardial cells. The implications of these results in the diagnosis of heart failures are discussed.

A 14-year-old boy with rhabdomyosarcoma (RMS) of the left palm showed increased concentration and activity of creatine kinase (CK; EC 2.7.3.2) MB in his serum. CK isoenzyme analysis revealed no extra band. Other laboratory data including high lactate dehydrogenase (LD) isoenzyme 2, CK isoenzyme BB and MB, neuron specific enolase (NSE), and clinical findings did not support the diagnosis of myocardial infarction. The high activity and concentration of CK-MB in serum is possibly originated from the tumor. We could follow his time-course and analyze laboratory data of him and other 6 patients with RMS. We concluded that CK-MB, both concentration and activity, was the more sensitive marker of disease states of RMS than NSE and LD to follow up the patients with RMS.

In both normal chicks and chicks with hereditary muscular dystrophy the BB (brain) and MB (hybrid) isozymes were the predominant forms of creatine kinase (CK) activity in embryonic skeletal muscle. As myogenesis progressed, activity due to the MM (muscle) isozyme progressively increased, and by 1 week ex ovo, the MM isozyme accounted for approximately 97% of total muscle activity in both genotypes. During this time, the proportion of the MM isozyme was slightly but significantly lower in dystrophic muscles. After hatching the proportion of the MB isozyme and its total activity decreased in normal muscle, but increased in dystrophic pectoral muscle, and by 5 months ex ovo, the MB isozyme accounted for 10% of total CK activity. Prior to hatching there was no consistent difference in total CK activity between normal and dystrophic tissues, but by 1 week after hatching and thereafter, total CK activity was significantly lower in dystrophic pectoral muscle.

Creatine kinase (CK) isoenzyme, CK-BB, known as the brain fraction, is not normally present in serum but predominates in several normal and malignant tissues and body fluids. We recently reported increased CK-BB levels in suction blister fluid. In the present study the cellular origin of the enzyme in skin was studied from homogenates of blister top epidermis and blister base dermis as well as from homogenates of split skin dermatome shavings and isolated keratinocytes. The CK-BB in human skin was derived almost exclusively from the epidermis. Enzyme determinations from various spontaneous bullae suggest that all types of skin blisters initially contain high CK-BB levels.

Keratinocytes have recently been reported to contain creatine kinase (CK) of brain-type isoenzyme. The aim of this study was to investigate whether necrosis of keratinocytes induced raised CK levels in toxic epidermal necrolysis (TEN). The serum and blister fluid levels of creatine kinase and its isoenzymes [muscular-type (MM), brain-type (BB), myocardial-type (MB)] were measured in 40 patients with TEN, 10 patients with other bullous dermatoses, and in suction blisters in five controls. The mean serum CK was significantly higher in TEN patients than in patients with other bullous dermatoses (mean +/- SD: 480 +/- 535 U/l vs. 107 +/- 44 U/l, P < 0.05). The MM-isoenzyme was predominant (94%). A positive correlation was found between the level of the serum CK and the percentage of body surface area (BSA) involved (r = 0.49, P < 0.001). The mean blister CK was significantly higher in TEN patients than in patients with other bullous dermatoses or controls (mean +/- SD: 728 +/- 437 U/l vs. 310 +/- 244 U/l and 268 +/- 194 U/l, respectively, P < 0.02). The isoenzyme distribution of blister CK in TEN patients was: 76.8% MM, 18.1% MB and 5% BB. Although a significant part of blister CK comigrating with CK-MB, after preincubation with protein A-Sepharose, appeared to be CK-BB/IgG complex, the CK-BB fraction constituted less than 25% of blister CK. Therefore, the CK present in increased amounts in serum and blister fluid in TEN was not directly produced by keratinocytes.

Using a specific radioimmunoassay for enzymically inactive creatine kinase (EC 2.7.3.2) B protein (CK-Bi), we studied 139 patients with various malignancies. We found it to be increased in certain adenocarcinomas, including colorectal, lung, and prostate, as has also been reported for enzymically active CK-BB. Of 15 patients with leukemia or lymphomas with active disease, 12 also had increased values for CK-Bi in plasma. In these patients, concentrations of CK-Bi in plasma tended to correlate with disease activity, increasing with aggressive malignancy and decreasing on successful treatment. Thus, measurement of CK-Bi may constitute a sensitive means for detecting malignancy and, in certain subsets of patients, for monitoring therapeutic response.

The typical creatine kinase (CK) isoenzymes include CK-BB, CK-MB, and CK-MM. Macro CK type 1, one of the atypical CK enzymes, has been identified in human serum, but the clinical significance still remains uncertain. In our laboratory, 105 patients who expressed serum macro CK isoenzyme type 1 were identified from March 2004 to March 2007. We found that macro CK type 1 recurred after at least one month in 16 patients. Clinical diagnoses were myopathy in 14 patients, sepsis in one, and acute coronary syndrome in one. The averages of serum total CK and macro CK type 1 were 9,132 and 1,925 (U/L), respectively. The linear regression analysis between recurrent macro CK type 1 and total CK revealed a good correlation (y=3.5054x+2381.3, R(2)=0.7822, P<0.001). Three patients had critical illness, including one respiratory failure and two mortalities. Good linear correlation is documented between total CK and recurrent macro CK type 1. In conclusion, the macro CK type I isoenzyme recurred primarily in patients with myopathy.

A centrifugal analyzer method was developed for measuring the MB isoenzyme of creatine kinase (EC 2.7.3.2) in serum by use of a specific immunochemical technique that avoids interference from CK-BB and adenylate kinase. Enzymatic activity was measured kinetically at 30 degrees C with an optimized reagent containing creatine phosphate as substrate. The precision (CV) of the assay was 5 to 12 percent day-to-day (n = 39). The reference interval was 0 to 3.5 U per L (n = 45). Patient samples without detectable CK-MB in a widely-used electrophoretic assay contained up to 12 U per L of CK-MB by the new method. The new test was evaluated carefully in 99 patients consecutively admitted to the coronary care unit. Blood samples were obtained at frequent (four to eight hr) intervals. All patients with acute myocardial infarction (n = 27) had peak CK-MB greater than 7 U per L and greater than 3.5 percent of total CK. The predictive value of this result was 94 percent for the diagnosis of infarction. Abnormal results were documented at the same times (+/- four hr) following infarction by the electrophoretic and immunochemical techniques. Guidelines were evolved for interpreting the percent of MB (i.e., MB per total CK) at various time points. The test was reliable in documented early recurrent infarctions that occurred in three patients. The method appears to be an attractive alternative to electrophoretic techniques for use in diagnosis of acute myocardial infarction.

There are conflicting reports of an increase in the activity of creatine kinase BB isoenzyme (CK-BB) in the serum of patients with cerebrovascular disease. The serum CK-BB activity of 33 patients with ischemic brain infarction, subarachnoid hemorrhage or intracerebral hemorrhage was measured with a bioluminescence method (CK-B Kit, LKB-Wallac) in combination with immunoprecipitation. The results were compared with lesions determined by computed tomography. In the control group (N = 19) there was a mean activity of 0.35 +/- 0.26 U/l (means +/- SE). In patients with small lesions (N = 11) the activity was 0.41 +/- 0.21 U/l, which was not significantly elevated when compared to the control group (Mann/Whitney U test). Therefore, patients with more extensive lesions (N = 12) and the group with severe lesions (N = 10) showed a significant elevation, with a mean activity of 0.61 +/- 0.34 U/l and 1.12 +/- 0.52 U/l, respectively. The group with severe lesions had a maximum activity on the first day after the initial symptoms.

Creatine kinase BB isoenzyme (CK-BB) was detected intraoperatively in 22 of 25 patients undergoing aortocoronary bypass surgery, both in the coronary sinus and in the mixed venous blood. In a group of 10 patients in whom selective intracavitary profound hypothermic arrest was used, CK-BB values were lower than in another group of 10 patients, in whom controlled ventricular fibrillation with moderate total body hypothermia was instituted. This latter group also had higher levels of CK-MB. Patients who developed acute myocardial infarction immediately prior to or during the surgical intervention had the highest CK-BB values. This enzyme appeared as early as 15 minutes after the institution of cardiopulmonary bypass and disappeared within 6 hours. It is considered that part of the BB isoenzyme in serum of patients undergoing heart surgery is of myocardial origin.

Abnormal creatine kinase (CK) isoenzyme patterns were observed in the serum of a 64-year-old woman with severe heart disease. Agarose electrophoresis revealed the presence of all the usual CK isoenzymes (MM, MB, and BB) plus an extra band between MM and MB. Total serum CK activity was within the normal range. Within 2 h after the patient suffered cardiorespiratory arrest, a fifth CK isoenzyme appeared, cathodal to MM. After cardiac valve replacement, the patient's serum showed a high activity of CK, but the isoenzyme pattern showed only MM and, transiently, an MB band. With return of the serum CK activity to normal, the CK isoenzymes pattern also became normal, virtually ruling out genetic variant(s). The abnormal CK isoenzyme patterns might have been the consequence of severe hypoxemia in the patient, thus such patients may represent an ominous prognostic sign. The association of the abnormal pattern upon admission with rapid deterioration of the condition of the patient suggests prompt attention for the prevention of complications.

Creatine kinase (CK) (total and isoenzymes) was measured in cultures obtained by dissociation and subsequent plating of cells from biopsied quadriceps muscle of 10 patients with Duchenne muscular dystrophy (DMD) and 20 controls. The total cellular CK and CK-MM reached highest values around 21 days in both DMD and control cultures, suggesting that DMD cultures do not show delayed myoblast fusion. There was a significant decrease of total cellular CK in DMD cultures at all stages, but the maximum differences were noted for the peak values. The CK isoenzyme pattern in DMD cultures demonstrated a higher percentage of CK-BB and CK-MB and a lower percentage of CK-MM than was observed in cultures from the controls. Addition of cytosine arabinoside after myoblast fusion to muscle cell cultures did not induce significant changes of CK isoenzyme pattern. There was no difference in the CK levels in culture medium from controls and DMD patients. The alterations of cellular CK were similar in fresh muscle and cell cultures from DMD patients.

BB-CK activity was measured in 11 patients with stroke and in 10 controls. Blood samples were taken 36 hours after the clinical stroke onset in every patient. Sera were stored at -80 degrees and analyzed within two months. The creatine kinase isoenzymatic pattern was determined by ion-exchange column separation and gradient elution system. The mean BB-CK concentration in patients with stroke was significantly higher than in controls (p less than 0.01). In the group of "stroke" patients we found a correlation between severity of brain damage, as suggested by the clinical picture and CT scans, and serum values of BB-CK.