Case Description
A 62-year-old female with a history of schizophrenia was found unresponsive after ingesting supratherapeutic amounts of diltiazem and valsartan. At presentation to the emergency department, she was hypotensive and bradycardic. Eight hours later, a blood sample (Fig. 1A) was drawn for chemistry analysis and ultracentrifuged to clarify the turbidity (Fig. 1B). However, the lab was unable to assay the plasma sample. Multiple samples yielded similar findings. Plasma samples obtained the following day were appropriate for analysis.
Questions
What interfering substances are causing the plasma's strawberry milk appearance?
What off-label medication was administered to this patient?
What drug(s) may be responsible for causing the abnormal appearance of her plasma?
The answers are below.
Answers
The combination of lipemia and hemolysis caused the plasma's strawberry milk appearance. Lipid emulsion is designed to be infused slowly as part of a total parenteral nutrition regimen. However, this patient received a 120-mL IV bolus of lipid emulsion off-label for its “lipid sink” action against supratherapeutic levels of lipid soluble drugs, such as diltiazem (1). Both lipid emulsion and diltiazem can cause erythrocyte fragility, which may account for the in vivo hemolysis (2–5).
Footnotes
Author Contributions: All authors confirmed they have contributed to the intellectual content of this paper and have met the following 3 requirements: (a) significant contributions to the conception and design, acquisition of data, or analysis and interpretation of data; (b) drafting or revising the article for intellectual content; and (c) final approval of the published article.
Authors' Disclosures or Potential Conflicts of Interest: Upon manuscript submission, all authors completed the author disclosure form. Disclosures and/or potential conflicts of interest:
Employment or Leadership: R.A. Sivak, UPMC Presbyterian Hospital Lab.
Consultant or Advisory Role: None declared.
Stock Ownership: None declared.
Honoraria: None declared.
Research Funding: None declared.
Expert Testimony: None declared.
Patents: None declared.
- Received for publication November 20, 2013.
- Accepted for publication December 11, 2013.
- © 2013 The American Association for Clinical Chemistry