Highly elevated lactate dehydrogenase level in a healthy individual: a case of macro-LDH

Lactate dehydrogenase in dermatology practice

Lactate dehydrogenase (LDH) is used in dermatology practice, particularly as a prognostic marker for cutaneous lymphoma. LDH is an intracellular enzyme involved in anaerobic glycolysis, and is found at low concentrations in the blood. LDH is produced in every tissue, thus cell damage releases LDH into the circulation, so the causes of elevated LDH levels are multiple. The utility of LDH in dermatology practice is reviewed, alongside current diagnostic and staging guidelines.

Serum lactate levels are associated with glioma malignancy grade

OBJECTIVE

Recent studies have suggested that high grade gliomas are associated with elevated serum lactate concentrations. The aim of the present study is to assess these findings in a sample of patients.

PATIENTS AND METHODS

We reviewed the anesthetic charts of patients with low-grade and high-grade glioma who underwent resection surgery and collected serum lactate concentration before tumor resection, as well as other demographic and tumor-related data (age, gender, WHO grade, and size of the tumor). A statistical comparison between patients with normal (<2 mmol/L) and elevated (≥ 2 mmol/L) serum lactate was performed.

RESULTS

We included a total of 152 patients (mean age 49.07 years). 62.5% of patients (n = 95) had a high-grade glioma and 37.5% (n = 67) a low-grade glioma. The multivariate regression showed that high grade gliomas had significantly higher lactate concentration (p < 0.01). The OR for elevated pre-resection serum lactate increased from 4.94 to 14.33 after adjusting for age and pre-surgical corticosteroid use, and the AUC for the final regression model was 0.98.

CONCLUSION

This study reinforces the role of serum lactate as a potential biomarker of brain tumors malignancy, and its results encourage further research on this subject, in order to improve the understanding of this phenomenon and to assess its potential as prognostic and therapeutic monitoring tool.

Observation and identification of lactate dehydrogenase anomaly in a postburn patient

OBJECTIVE

Lactate dehydrogenase (LDH) anomaly is one of the macroenzymes. Macroenzymes are enzymes in serum that have formed high molecular mass complexes, either by self polymerisation or by association with other serum components. The aim of this study was to identify the properties of LDH anomaly and observe the changes from admission to discharge in a postburn patient with LDH anomaly in his serum.

METHODS

LDH isoenzymes of the serum were electrophoretically fractionated with terylene cellulose acetate supporting media; LDH anomaly was identified by counter immunoelectrophoresis.

RESULTS

An abnormal LDH-4 band and an extra band on the cathode of LDH-5 were observed in the serum of this patient and were found to be part of an LDH-IgG complex. As his symptoms improved, the patient's LDH anomaly gradually disappeared. The appearance and disappearance of the anomaly seemed to be related to the progression of the patient's burns.

CONCLUSION

In clinical practice, it is important to keep in mind the possibility of an LDH anomaly in patients when the LDH level is abnormally high or does not seem to be related to the clinical state. Early discovery of an LDH anomaly in a patient's serum may be useful for diagnosis and treatment.