A review of the possible role of the essential fatty acids and fish oils in the aetiology, prevention or pharmacotherapy of schizophrenia.

WHAT IS KNOWN AND OBJECTIVE: Fish oils and other essential fatty acids have been purported to ameliorate the symptoms of schizophrenia or the adverse effects of the drugs that are used to manage it. Our objective is to review the basic and clinical evidence regarding replenishment of the reported decreased levels of polyunsaturated essential fatty acids, such as the omega-3 docosahexaenoic acid, the omega-6 linoleic and arachidonic acids, in brains of patients with schizophrenia. METHODS: We summarize the literature related to the postulated mechanistic connection between essential fatty acids and schizophrenia and the clinical trials testing fatty acids in patients with schizophrenia. RESULTS AND DISCUSSION: Fatty acids play critical roles in cell membranes of neurons, and certain fatty acids appear to be abnormally low in brains of patients with schizophrenia. The attempt to enhance endogenous levels thus seems a rational and worthwhile goal. The value of such intervention awaits the results of ongoing trials. WHAT IS NEW AND CONCLUSION: Despite the limited evidence that supplements ameliorate symptoms of schizophrenia, given the low risk of harm, some clinicians might opt to add omega-3 polyunsaturated fatty acid to current drug regimens in hope of better symptomatic control in schizophrenia.

Definitive liquid-chromatographic demonstration that N-ethylglycine is the metabolite of lidocaine that interferes in the Kodak sarcosine oxidase-coupled method for creatinine.

Patients receiving lidocaine may show false increases of serum creatinine as assayed by the single-slide method on the Kodak Ektachem 700. Bissell et al. (Clin Chem 1987;33:951) suggested that this interference was due to oxidation of N-ethylglycine (NEG), a previously uncharacterized metabolite of lidocaine, by the sarcosine oxidase preparation used in the Ektachem creatinine slide. To investigate this possibility, we synthesized NEG, added it to drug-free human serum, and analyzed the NEG-supplemented sera for creatinine with the Ektachem 700. We found the following linear relationships between creatinine bias (y, mg/L) and NEG concentration (x, mg/L) for first (I), third (III), and fourth (IV) generation slides: I: y = 1.70x - 0.8 mg/L (n = 13, r = 1.0) III: y = 0.39x - 0.3 mg/L (n = 3, r = 1.0) IV: y = 0.79x - 1.8 mg/L (n = 13, r = 1.0) Using HPLC, we directly demonstrated the presence of NEG in sera of patients receiving lidocaine and quantified NEG concentrations in sera from four of these patients. The increasing artifactual bias in creatinine with increasing NEG concentration unequivocally confirmed that NEG is responsible for the lidocaine-associated interference in the Kodak Ektachem single-slide creatinine method.

Usefulness of immunofixation electrophoresis in the clinical laboratory.

The published experience of a number of investigators shows that IFE has a proven role in the analysis of monoclonal immunoglobulins. This role is not as a replacement for IEP but as an essential supplement to IEP and routine protein electrophoresis in cases involving low concentrations of monoclonal protein.