Serum Lactate Dehydrogenase Isoenzyme Research Articles

Serum lactate dehydrogenase and its isoenzymes as predictors of clinical outcomes in acute exacerbation of chronic obstructive pulmonary disease: a retrospective analysis of a hospitalized cohort.

We aimed to test the relationship between serum lactate dehydrogenase (LDH) and its isoenzymes and treatment outcomes during hospitalization for acute exacerbations of chronic obstructive pulmonary disease (AECOPD). Thirty-eight AECOPD patients were recruited from a tertiary hospital from December 2017 to June 2018. Serum LDH and LDH isoenzymes were measured on venous blood collected at admission. Treatment outcomes included duration of hospital stay, initiation of mechanical or non-invasive ventilation (NIV), initiation of antipseudomonal antibiotics, change in empirical antibiotic treatment, need for intravenous corticosteroids or methylxanthines, and percentage of change in C-reactive protein from admission to the third day. Multivariate linear and binary logistic regression analyses were used to test the study's objectives. We found that, after adjusting for age, gender, comorbidities, COPD severity, level of hypoxemia, and inflammation markers, each 10 U/L increase in serum LDH was associated with prolongation of the hospital stay by 0.25 (0.03, 0.46) days, 42% higher odds [odds ratio (OR) 1.42 (1.00, 2.03)] for need of NIV, and 25% higher odds [OR 1.25 (1.04, 1.49)] for initiation of antipseudomonal treatment. LDH1 and LDH2 were the LDH isoenzymes that mainly drove these relationships. LDH release in the context of an AECOPD could originate from lung, muscle, or heart tissue damage due to airway inflammation, respiratory muscle recruitment, and myocardial stress. Myocardial injury and aerobic adaptation in respiratory muscles may explain the predominance of LDH1 and LDH2 isoenzymes in these associations.

Agarose gel electrophoresis pattern of serum creatine kinase and lactate dehydrogenase isoenzymes in zoo-managed Asian elephants (Elephas maximus).

Serum levels of creatine kinase (CK) and lactate dehydrogenase (LDH) isoenzymes were evaluated in nine zoo-managed Asian elephants (Elephas maximus) using a commercial agarose gel electrophoresis (AGE) kit. CK was separated into two major fractions, CK-BB and CK-MM, along with a small fraction of macroenzyme-CK type 2 (mCK2); CK-MM was the largest fraction. LDH was separated into five fractions (LDH1-5); LDH3 was the largest fraction. Age was negatively and positively correlated with the percentages of CK-BB and CK-MM, respectively, and negatively correlated with CK-BB and mCK2 activities. These results indicate that an AGE kit can be used to evaluate CK and LDH isoenzymes. Routine isoenzyme testing may enable early detection of disease and physiological changes.

Lactate dehydrogenase isoenzymes in patients with acute exacerbation of chronic obstructive pulmonary disease: An exploratory cross-sectional study

We aimed to evaluate differences in serum lactate dehydrogenase (LDH) isoenzymes between patients hospitalized for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and other lower respiratory tract infections (LRTIs). Based on self-reported COPD diagnosis, 71 participants were divided into AECOPD (n = 38, 29 males, mean age 70.5 years) and LRTI (n = 33, 12 males, mean age 70.4 years) groups. Information on demographics, comorbidities, and COPD severity markers, as well as arterial blood gases and laboratory data were collected, while serum LDH electrophoresis was performed to examine the LDH isoenzymes. Adjusting for sex, age, comorbidities, degree of hypoxemia, inflammation markers, muscle and myocardial enzymes, and total serum LDH, the mean differences (95 % confidence intervals) in the ratios of serum LDH isoenzymes to total serum LDH between groups (LDHxAECOPD − LDHxLRTI) were statistically significant for LDH1 [4.9 (1.4 to 8.3)], LDH2 [3.0 (0.1 to 5.8)], LDH3 [−4.3 (−6.3 to −2.3)], and LDH4 [−3.2 (−4.9 to −1.5)]. A sum of LDH3 and LDH4 ratios below 29 % had the highest discriminative ability to classify a subject in the AECOPD group (AUC 0.841, sensitivity 76 %, specificity 87 %). Aerobic metabolic adaptive mechanisms in respiratory muscles during AECOPD could explain the above differences.

Clinical and Diagnostic Significance of Lactate Dehydrogenase and Its Isoenzymes in Animals.

Lactate dehydrogenase (LDH) is widely distributed enzyme in cells of various living systems where it is involved in carbohydrate metabolism catalyzing interconversion of lactate and pyruvate with NAD+/NADH coenzyme system. Cells of tissues are direct source of lactate dehydrogenase isoenzymes that are naturally distributed in blood plasma/serum of animals and humans producing characteristic profile. This profile depends on intracellular isoenzyme concentration in all tissues that contribute to the common pool of lactate dehydrogenases in plasma/serum as a consequence of natural cell degradation. LDH is widely distributed in the body, high activities are found in the heart, liver, skeletal muscle, kidney, and erytrocytes, whereas lesser amounts are found in the lung, smooth muscle, and brain. Because of its widespread activities in numerous body tissues, LDH is elevated in a variety of disorders. There are many conditions that contribute to increased activity of LDH. An elevated total LDH value is a rather nonspecific finding. Therefore, LDH assays assume a more clinical significance when separated into isoenzyme fractions. The activity of LDH and its serum and tissue patterns and composition show great variations between the species. These differences do not allow using catalytic activities of LDH isoenzymes from one species to another. Instead, the pattern of serum LDH isoenzymes should be interpreted in respect to its species origin that is important in particular in veterinary medicine. Determination of total LDH activity and its isoenzyme pattern in serum of mammals had become one of the biochemical indicators in the assessment of organ disorders. When the content of cells is released from tissue to plasma, as on cell injury, the LDH isoenzyme pattern of the serum changes in favour of the profile of the affected organ (tissue) that can be used in the diagnostic practice.

LDH isoenzyme 5 is an index of early onset muscle soreness during prolonged running.

Muscle soreness is also induced during prolonged running such as a full marathon, and muscle soreness and increased damage markers are detected immediately after such a running. We named this muscle soreness, early onset muscle soreness (EOMS). Additionally, lactate dehydrogenase (LDH) level which has some isoenzyme is increased immediately after prolonged exercise. However, it is unclear that EOMS is related to muscle damage markers on prolonged running. This study aimed to determine at which point EOMS, and muscle damage markers are related to EOMS during prolonged running. We studied 11 male subjects who habitually perform aerobic exercise. They ran 30 km at 90% of ventilatory threshold intensity. Every 10 km, we estimated perceived muscle soreness, and sampled blood to measure muscle and liver damage, inflammation, and oxidative stress (d-ROM and BAP) markers. Muscle soreness score lower limbs were significantly appeared at 20 km compared to that at 0 km. Serum lactate dehydrogenase (LDH) level increased at 30 km compared to that at 0 km. LDH isoenzymes 3, 4, and 5, and neutrophils significantly increased at 30 km compared to those at 0 km. Serum LDH isoenzyme 5 and change in aspartate aminotransferase significantly increased at 20 km. In addition, there was a significant correlation between the thigh NRS and amount of serum LDH isoenzyme 5 from 0 km to 20 km. d-ROM and BAP increased at 10 km compared to those at 0 km. EOMS started to occur at 20 km during a 30 km running task. Our data suggest that LDH isoenzyme 5 is a marker of occurrence in EOMS during prolonged running.

A more accurate method to interpret lactate dehydrogenase (LDH) isoenzymes’ results in patients with uterine masses

ObjectiveSince there are no approved reliable biomarkers for detecting preoperatively uterine sarcoma, lactate dehydrogenase (LDH) isoenzymes are usually required. We first evaluated the role of LDH isoenzymes in detecting uterine sarcoma risk, and then we tried to introduce a model to easily interpret the biochemical results. MethodsWe retrospectively retrieved records of patients who underwent surgical treatment for uterine masses from 2004 to 2016, and we compared data of 2211 patients with a definitive surgical diagnosis of uterine fibroids and 43 with uterine sarcomas. Quantitative relationships between serum LDH isoenzymes levels, as different single markers or in multiple assays, and the final diagnosis were investigated. ResultsLDH isoenzymes levels significantly differed between patients with benign uterine masses or sarcomas. LDH3 isoenzyme exhibited better predictive performances than the other four isoforms. Combining LDH3 with LDH1 isoenzymes into an inverse algebraic relationship, named Uterine mass Magna Graecia (U.M.G.) risk index, the accuracy of markers in discriminating between benign and suspicious malignant uterine masses was significantly enhanced, sensitivity at 100% and specificity at 99.6%, with nine false positive over 2211 benignant cases and no false negative over 43 sarcomas. ConclusionsThis retrospective analysis suggests to consider U.M.G. risk index as an inexpensive and accurate prognostic index that, once validated in a prospective study, may help clinicians in discriminating between benignant and suspicious malignant uterine masses.

Serum lactate dehydrogenase isoenzymes 4 plus 5 is a better biomarker than total lactate dehydrogenase for refractory Mycoplasma pneumoniae pneumonia in children

Although usually self-limiting, Mycoplasma pneumoniae pneumonia (MPP) may lead to clinical or radiological deterioration despite macrolide antibiotic therapy, resulting in the development of refractory MPP (RMPP). Corticosteroids have been used to treat RMPP with beneficial effects. Serum lactate dehydrogenase (LDH) is a suggested biomarker for the use of steroid therapy. Since serum LDH is a non-specific marker and elevated in many inflammatory processes, this study investigates the predicting level of LDH isoenzymes for RMPP. Fifty-four children with non-refractory M. pneumoniae pneumonia (NRMPP) and 16 children with RMPP were enrolled in this study. In comparison to the NRMPP group, the RMPP group showed significantly higher levels of serum LDH. Concerning LDH isoenzymes, the RMPP group showed significantly lower proportions of LDH1 and LDH2, while higher LDH4 and LDH5 percentage. Receiver operating characteristic curve analysis showed that the area under the curve for the total LDH data was 0.812 with a cut-off of 408IU/L (sensitivity of 75.0%, specificity of 72.2%). The areas under the curve for LDH4, LDH5, and [LDH4+LDH5] were estimated to be 0.813, 0.818, and 0.829, respectively. The threshold for [LDH4+LDH5] was estimated to be 109.4IU/L (sensitivity, 75.0%; specificity, 87.0%). These results indicate that for the initiation of corticosteroid therapy, serum [LDH4+LDH5] level is a more sensitive biomarker than total LDH.

Monitoring a 'metabolic shift' after surgical resection of oral squamous cell carcinomas by serum lactate dehydrogenase.

Monitoring surgical removal of oral squamous cell carcinomas (OSCC) is being routinely performed through clinical and imaging follow-up. We analyzed the potential use of serum lactate, lactate dehydrogenase (LDH), and LDH isoenzymes (LDH 1-5) as biomarkers in blood for the monitoring of surgical removal of OSCC. Serum lactate, LDH, and LDH isoenzymes (LDH 1-5) have been prospectively assessed in healthy individuals (n = 19), patients with OSCC (n = 34: primary OSCC, n = 32 and recurrent OSCC, n = 2) before surgery and after curative tumor resection (n = 26). LDHA and LDHB expressions were analyzed by immunohistochemistry (IHC) in the same OSCC tumor specimen. Positive LDHA tumor tissue expression measured by IHC (n = 34/34, 100%) was significantly associated with increased serum LDH-5 (n = 24/34, 71%, P = 0.0258) but weak significantly associated with increased total serum LDH (n = 23/34, 68%, P = 0.0592). Positive LDHB tumor tissue expression measured by IHC (n = 25/34, 74%) was significantly associated with increased total serum LDH (P = 0.0172). After surgery, serum LDH and LDH-5 isoenzyme significantly decreased and LDH-1 significantly increased in the aftercare. A significantly inverse correlation of LDHA with LDHB IHC scores was found (P < 0.0001). The association of LDHA and LDHB measured by IHC with serum LDH indicates that analyzing this enzyme could serve as a favorable 'liquid biopsy' (non-invasive diagnostic tool) for OSCC.

Implications of oxidative stress in occupational exposure to lead on a cellular level

The aim of this study was to determine oxidative alterations leading to cellular dysfunctions in Pb-exposed subjects by evaluating damage to all major classes of biomolecules in the cell, lipid peroxidation, protein and DNA damage and determine relationships between parameters of Pb toxicity and specific biomarkers of oxidative damage.Analysis was conducted of smelter workers with high blood Pb and urine aminolevulinic acid levels and slightly elevated values of coproporphyrin and erythrocyte protoporphyrin IX. Significant decreases of thiol groups and increases in carbonyl groups as protein degradation end products, and of nitrite were detected. Elevated rates of lipid peroxidation and rises in the activities of the antioxidant enzymes Cu–Zn superoxide dismutase and catalase were also observed. Both enzymes showed positive correlations with the blood lead levels and urine coproporphyrin, while thiol groups correlated negatively with the same indices. The genotoxic potential of lead was manifested through an increased number of DNA-damaged cells. Increased activities of serum lactate dehydrogenase isoenzymes indicated cellular damage in the lungs, kidneys, and liver. These lead-induced impairments should be taken into consideration in the assessment of Pb-related health hazards.

Determination of optimal storage temperature and duration for analysis of total and isoenzyme lactate dehydrogenase activities in canine serum and cerebrospinal fluid.

Lactate dehydrogenase (LDH) exists as 5 isoenzymes in both serum and cerebrospinal fluid (CSF). Human studies have demonstrated that changes in LDH activity can be correlated with a particular disease. Conflicting reports regarding the stability of LDH made it necessary to determine storage conditions before further study of the diagnostic power of this enzyme's activity can be pursued in dogs. The purpose of this study was to optimize measurement of LDH activity and analysis of its isoenzyme profile in canine serum and CSF through proper storage. Serum and CSF were collected from 5 healthy dogs. Samples were stored at 22°C, 4°C, or -20°C for up to 2months. Total LDH activity was measured spectrophotometrically. Isoenzyme profiles were determined using the QuickGel LDH Isoenzyme technique and densitometric scanning. Retention of >70% LDH activity in stored samples was considered clinically acceptable. Serum and CSF stored at -20°C retained >85% of the total LDH activity for 4weeks, although CSF total LDH activity degraded by >10% within 24hours of storage. All serum LDH isoenzymes retained >85% activity for up to 4weeks at -20°C. CSF LDH isoenzyme activity degraded rapidly, therefore CSF LDH should be evaluated within 72hours to assure >75% of LDH isoenzyme activity. Proper storage at -20°C can optimize detection of total LDH activity and the LDH isoenzyme profile in canine serum and CSF. This information is important for evaluating the potential usefulness of LDH in veterinary medicine.

Lactate dehydrogenase as a possible indicator of reproductive capacity of boars

The aim of this study was to determine the activity of lactate dehydrogenase (LDH) and its isoenzymes in the blood serum and seminal plasma of boars from the breeding and insemination centre with regard to their age. Significant quantitative differences in the presence of isoenzymes between blood serum and seminal plasma were recorded. Isoenzyme LDH-C4 in the seminal plasma of breeding boars of both groups was identified in the position between the third and fourth fraction of LDH, although boars from the breeding centre showed significantly lower concentrations. Refrigeration had a negative influence on the activity of LDH isoenzymes in the blood serum after 7 days and in seminal plasma after 3 days of storage. The work extends the knowledge in an insufficiently examined field of veterinary medicine: the distribution and physiological function of LDH in boars focusing on isoenzyme LDH-C4 in seminal plasma.

Preventive effects of zingerone on altered lipid peroxides and nonenzymatic antioxidants in the circulation of isoproterenol-induced myocardial infarcted rats.

The present study was designed to evaluate the preventive effects of zingerone on circulatory lipid peroxides and nonenzymatic antioxidants in isoproterenol-induced myocardial infarcted rats. Rats were pretreated with zingerone (6 mg/kg body weight) daily for a period of 14 days and were then induced myocardial infarction with isoproterenol (100 mg/kg body weight) on 15th and 16th day. Increased intensities of serum lactate dehydrogenase isoenzymes 1 and 2 bands enhanced plasma lipid peroxidation products and lowered nonenzymatic antioxidant system were noted in isoproterenol-induced rats. Pretreatment with zingerone daily for 14 days revealed significant preventive effects on the electrophoretic and biochemical parameters evaluated in isoproterenol-induced rats. Furthermore, the in vitro study confirmed the potent antioxidant activity of zingerone. The results of our study showed that zingerone protected the rat's heart against isoproterenol-induced myocardial infarction by its antioxidant effect.

Importance of glycolysis and oxidative phosphorylation in advanced melanoma.

Serum lactate dehydrogenase (LDH) is a prognostic factor for patients with stage IV melanoma. To gain insights into the biology underlying this prognostic factor, we analyzed total serum LDH, serum LDH isoenzymes, and serum lactate in up to 49 patients with metastatic melanoma. Our data demonstrate that high serum LDH is associated with a significant increase in LDH isoenzymes 3 and 4, and a decrease in LDH isoenzymes 1 and 2. Since LDH isoenzymes play a role in both glycolysis and oxidative phosphorylation (OXPHOS), we subsequently determined using tissue microarray (TMA) analysis that the levels of proteins associated with mitochondrial function, lactate metabolism, and regulators of glycolysis were all elevated in advanced melanomas compared with nevic melanocytes. To investigate whether in advanced melanoma, the glycolysis and OXPHOS pathways might be linked, we determined expression of the monocarboxylate transporters (MCT) 1 and 4. Analysis of a nevus-to-melanoma progression TMA revealed that MCT4, and to a lesser extend MCT1, were elevated with progression to advanced melanoma. Further analysis of human melanoma specimens using the Seahorse XF24 extracellular flux analyzer indicated that metastatic melanoma tumors derived a large fraction of energy from OXPHOS. Taken together, these findings suggest that in stage IV melanomas with normal serum LDH, glycolysis and OXPHOS may provide metabolic symbiosis within the same tumor, whereas in stage IV melanomas with high serum LDH glycolysis is the principle source of energy.

Correlation of lactate dehydrogenase (LDH) isoenzyme profile with outcome in advanced colorectal cancer (CRC) patients (pts) treated with chemotherapy and bevacizumab (BEV) or cediranib (CED).

e13541 Background: There is a clinical need for predictive biomarkers of efficacy of VEGF signaling inhibitors (VSIs). LDH is a tetramer that can include any combination of the M and H subunits. LDH4 and 5 isoenzymes are composed mostly of the M subunit and are more abundant in hypoxic conditions. We speculated that the levels of LDH isoenzymes in pts serum may correlate with outcome of pts treated with VSIs. HORIZON I trial enrolled pts that were randomized to mFOLFOX6 with BEV or CED. A retrospective exploratory analysis was performed on baseline serum samples of these pts. Methods: Total serum LDH was tested on fresh samples during the conduct of the trial. About 2 years after the trial, frozen samples stored at -70 degrees were tested for total serum LDH and LDH isoenzymes, measured by agarose electrophoresis and a colorimetric enzymatic assay. Relative levels of M and H subunits were derived based on the known structure of each isoenzyme. Progression free survival (PFS) and overall survival (OS) were compared by subgroups of total LDH and LDH isoenzyme levels. P values were not calculated for these exploratory analyses. Results: Baseline total LDH levels from fresh serum were available for 207 pts. Total and isoenzyme LDH levels were available for frozen serum samples of 189 pts. Total LDH in the frozen and fresh samples correlated (R=0.9). Distant isoenzymes (e.g. LDH1 and 5) were negatively correlated. High M/H subunits ratio correlated with poor OS (HR=1.804, 95%CI 1.24-2.620). A non-significant trend for better OS to CED-treated vs. BEV-treated pts was seen in pts with high M/H ratio (e.g., CED 30mg vs BEV HR=0.685, 95%CI 0.382-1.23). Conclusions: Evaluation of LDH isoenzymes is feasible using serum samples kept frozen for 2 years. A negative correlation is seen between hypoxic-related and oxic-related isoenzymes. In CRC pts treated with a VSI, LDH isoenzyme hypoxia-associated profile correlates with poorer outcome. LDH isoenzyme profile as a possible predictive biomarker for benefit from CED vs. BEV requires further investigation.

Studies on Serum Lactate Dehydrogenase (S-LDH) Isoenzyme in Racehorses

Studies on Serum Lactate Dehydrogenase (S-LDH) Isoenzyme in Racehorses

Serum Creatine Kinase and Lactate Dehydrogenase Isoenzymes in Skeletal and Cardiac Muscle Damage in the Horse

Serum Creatine Kinase and Lactate Dehydrogenase Isoenzymes in Skeletal and Cardiac Muscle Damage in the Horse

Elevated serum lactate dehydrogenase isoenzymes and aspartate transaminase distinguish Albers-Schönberg disease (Chloride Channel 7 Deficiency Osteopetrosis) among the sclerosing bone disorders

Osteopetrosis (OPT) refers to the consequences of generalized failure of skeletal resorption during growth. Most cases are explained by loss-of-function mutation within the genes that encode either chloride channel 7 (CLCN7) or a vacuolar proton pump subunit (TCIRG1), each compromising acid secretion by osteoclasts. Patients suffer fractures and sometimes cranial nerve entrapment and insufficient medullary space for hematopoiesis. In 1996, we reported that a high serum level of the brain isoenzyme of creatine kinase (BB-CK), the CK of osteoclasts, characterizes OPT dueamong the sclerosing bone disorders (J Clin Endocrinol Metab. 1996;11:1438). Now, we show that elevation in serum of multiple lactate dehydrogenase (LDH) isoenzymes with aspartate transaminase (AST) distinguishes autosomal dominant OPT due to loss-of-function mutation in CLCN7 [Albers-Schönberg disease (A-SD)] among these conditions. Serum total LDH and AST levels as high as 3× and 2×, respectively, the upper limits of normal for age-appropriate controls, were persistent and essentially concordant in A-SD. Serum LDH was elevated in 7 of 9 children and in the 2 adults studied with A-SD. LDH isoenzyme quantitation showed excesses of LDH-2, -3, and -4. Neither total LDH nor AST increases were found in other forms of OPT, including bisphosphonate-induced OPT, or in 41 children and 6 adults representing 20 additional sclerosing bone disorders. Serum TRACP-5b and BB-CK also were markedly elevated in A-SD. Hence, high serum levels of several enzymes characterize A-SD. Elevated serum LDH isoenzymes and AST indicate a disturbance (of uncertain clinical significance) within multiple extraosseous tissues when there is CLCN7 deficiency.

Serum lactate dehydrogenase isoenzyme 1 as predictor of tumor-associated death in patients with testicular germ cell tumours.

Serum lactate dehydrogenase iso-enzyme 1 (S-LD-1) was determined in 24 patients with testicular germ cell tumours who died during follow-up. Serum samples were obtained at the start of chemotherapy or late into the clinical course for those without evidence of a tumour. Seven of the eight patients with tumour-associated death had S-LD-1 > 150 U l-1 (median 260 U l-1 range 90-905 U l-1, as did two of the six who died without evidence of a tumour (median 134 U l-1 range 89-128 U l-1) (P = 0.03, Mann-Whitney U-test, two-tailed). The remaining 10 patients had previously been reported as to prediction of S-LD-1 for the prognosis, and were evaluated only as to the reproducibility of the S-LD-1 determination. S-LD-1 was determined in two serum samples obtained concomitantly from eight of these 10 patients: the difference between the two S-LD-1 determinations was median 6% of the average of the two S-LD-1 determinations (25-75% range 3-17%). Our study showed an unforeseeable high level of imprecision of the assay system. Nevertheless, S-LD-1 determinations in the regular monitoring of patients with testicular germ cell tumours may be useful for predicting tumour-associated deaths.

A Study of Lactate Dehydrogenase (LDH) Isoenzyme is a Biochemical Tumour Marker in Cervical Carcinoma Patients

To establish Lactate dehydrogenase (LDH) isoenzyme is a biochemical tumor marker in cervical carcinoma patients for diagnosis and treatment monitoring of the disease. The Serum and cervical tissue LDH isoenzyme was analyzed qualitatively by Poly Acrylamide Disc Gel Electrophoresis method. The total LDH activity was estimated quantitatively by the method of UV spectrophotometry. 50 untreated cervical carcinoma patients were taken up and compared with age matched healthy females (controls). Out of 50 patients, 5 patients were histologically classified as well differentiated squamous cell carcinoma (Grade-I), 23 were moderately differentiated squamous cell carcinoma (Grade-II) and 22 were poorly differentiated squamous cell carcinoma (Grade-III). Grade-I patients did not show any change, in the serum and cervical tissue LDH isoenzyme fractions compared to the controls but variation in electrophoretic mobility have been observed. Grade-II patients showed two new additional isoenzyme fractions in LDH 2 and LDH 3 locations, where as Grade-III patients showed only three LDH isoenzyme fractions. The total LDH activity in both serum and cervix tissue of normal individuals are 0.458±0.0796 units/ml; and 0.680±0.0218 units/mg. Grade-I patients did not show any change in total LDH activity (serum: 0.384±0.0404 units/ml; cervical tissue: 0.589±0.0292 units/mg; P<0.01). Grade-III patients showed much lower values (serum: 0.284±0.0109 units/ml; cervical tissue: 0.327±0.043 units/mg; P<0.001), where as Grade-II patients showed significant increase in total LDH activity (serum: 0.878±0.0531 units/ml; cervical tissue: 1.296±0.0813 units/mg; P<0.001) respectively. The results suggest that LDH isoenzyme is useful biochemical tumor marker for diagnosis and to assess the grade of malignancy.

Adjustments of serum lactate dehydrogenase isoenzymes and their significance in monitoring the treatment in patients with tubercular pyothorax

The adjustments and diagnostic significance of polyacrylamide gel electrophoretic (PAGE) profiles of lactate dehydrogenase isoenzymes (LDH: 1.1.1.27) was evaluated in the sera and pleural fluid of patients with tubercular pyothorax. Sera and pleural fluid samples were randomly collected from 72 and 18 patients respectively at two different timings; first, when patients were admitted to the Hospital and second, after an intensive phase of treatment. Sera of 20 healthy individuals served as control. Our results demonstrate significant differences in sera LDH (sLDH) and pleural fluid LDH (pfLDH) isoenzymes. In patients the order of LDH isoenzyme in sera and pleural fluid followed: LDH-5>-4>-2>-3>-1 and LDH-5>-4>-3>-2>-1 respectively. The ranking of activity levels in control was LDH-2>-1>-3>-5>-4. In the second phase of sampling from 31 patients, values of sLDH isoenzymes showed recovery and resembled profiles of controls. Therefore, the sLDH zymograms of patients can be used as the prognostic marker, since they tend to reach the normal level during recovery signifying the effect of chemotherapy in hospitalized patients. Moreover, according to the present findings on LDH-PAGE profiles, the levels of LDH-5 and-4 rise in pyothorax patients significantly (P<0.05). This elevation along with the rise in total LDH activity may, therefore, be used in the diagnosis and monitoring of tubercular pyothorax.