Neutropenia and Leukopenia After Cross Taper From Quetiapine to Divalproex for the Treatment of Borderline Personality Disorder.

Background: Valproic acid (VPA) and its derivative, divalproex (DVP) can cause various hematologic dyscrasias, the most common being thrombocytopenia. Neutropenia and leukopenia have been reported in isolated cases, most occurring in pediatric patients or patients with epilepsy. We report a case of leukopenia and neutropenia that presented after cross taper from quetiapine to DVP for the treatment of borderline personality disorder. Case presentation: A 34-year-old male patient with history of posttraumatic stress disorder, opioid use disorder, alcohol use disorder, stimulant use disorder, cannabis use, and borderline personality disorder underwent a cross taper from quetiapine to divalproex (DVP). DVP was titrated to 1000 mg per day, complete blood count (CBC) was obtained after completion of cross taper and revealed neutropenia and leukopenia with no documented history of blood dyscrasias. Nine days after discontinuation of DVP, neutrophil and white blood cell count returned to normal limits. With a score of 7 on the Naranjo Adverse Drug Reaction Probability Scale, an adverse reaction of probable DVP-induced neutropenia was documented and medication was not resumed. Conclusions: This case suggests that there may be a correlation between DVP and isolated neutropenia and leukopenia. Although a CBC is collected routinely to monitor for thrombocytopenia, health care practitioners also should consider other blood dyscrasias. Further studies are warranted to determine incidence of neutropenia and leukopenia with DVP therapy and evaluate whether the medication can be safely continued in cases of mild-to-moderate neutropenia with close monitoring.