Data on hydroxychloroquine interference with urine laboratory testing.

Hydroxychloroquine is a medication used to treat rheumatoid arthritis, systemic lupus erythematosus, and other autoimmune disorders. Previous studies have shown that hydroxychloroquine and the structurally related drug chloroquine have the potential to interfere with some common urine chemistry tests, especially at high concentrations. In the related research article, we observed suspected interference with urine drug of abuse testing in a patient who ingested approximately 12 g of hydroxychloroquine in an acute overdose, with urine hydroxychloroquine concentrations exceeding 500 mg/L.

Diagnostic pitfalls and laboratory test interference after hydroxychloroquine intoxication: A case report.

Hydroxychloroquine is a medication used to treat autoimmune conditions. Overdoses of hydroxychloroquine are uncommon, with most recommendations on monitoring drawing from experience with more common overdoses of the related drug chloroquine. We present a case of an adolescent with intentional overdose of approximately 12 g of hydroxychloroquine.

Accidental intoxications in toddlers: lack of cross-reactivity of vilazodone and its urinary metabolite M17 with drug of abuse screening immunoassays.

Background: Vilazodone is an FDA approved medication used to treat major depressive disorder. The authors describe two cases of accidental vilazodone exposure in toddlers who presented with symptoms similar to amphetamine exposure and also with unexplained positive amphetamine urine immunoassay drug screens. Given a lack of published data on cross-reactivity of vilazodone and its metabolites with drug of abuse screening tests, the authors investigated drug of abuse immunoassay cross-reactivity of vilazodone and metabolites using computational and empirical approaches.

Ordering of the Serum Angiotensin-Converting Enzyme Test in Patients Receiving Angiotensin-Converting Enzyme Inhibitor Therapy: An Avoidable but Common Error.

Background: Serum angiotensin-converting enzyme (ACE) levels may be decreased by use of ACE inhibitor (ACEI) medication. In this study, we determined how often ACE levels were measured in patients receiving ACEI therapy.

Methods: ACE levels analyzed over a 54-month preintervention time period at an academic medical center were reviewed retrospectively for tests performed during ACEI therapy.

Cross-reactivity of steroid hormone immunoassays: clinical significance and two-dimensional molecular similarity prediction.

Background: Immunoassays are widely used in clinical laboratories for measurement of plasma/serum concentrations of steroid hormones such as cortisol and testosterone. Immunoassays can be performed on a variety of standard clinical chemistry analyzers, thus allowing even small clinical laboratories to do analysis on-site. One limitation of steroid hormone immunoassays is interference caused by compounds with structural similarity to the target steroid of the assay.