Predictive value of eosinophilia for neutropenia during clozapine treatment.
BACKGROUND
Myelotoxicity continues to hinder the widespread use of clozapine in the United States. It has been theorized that eosinophilia predicts later agranulocytosis and that agranulocytosis occurs due to an immunologic mechanism. Our study compares the rates of these dyscrasias in clozapine-treated patients and a control group.


METHODS
Forty-one patients taking clozapine and 29 patients taking haloperidol were monitored for a period of 6 months. Rates of eosinophilia and neutropenia were compared between the two treatment groups.


RESULTS
Treatment-emergent eosinophilia occurred frequently in both haloperidol- and clozapine-treated patients. No significant difference was seen between groups in the incidence of eosinophilia and neutropenia.


CONCLUSIONS
We find no statistical difference between the rates of eosinophilia or neutropenia in haloperidol- and clozapine-treated patients. This study does not support the use of eosinophilia as a reliable predictor of neutropenia.
Ames
D
D
UCLA School of Medicine, Department of Psychiatry and Biobehavioral Sciences, USA.
Wirshing
W C
WC
Baker
R W
RW
Umbricht
D S
DS
Sun
A B
AB
Carter
J
J
Schooler
N R
NR
Kane
J M
JM
Marder
S R
SR
D000328:Adult; D003024:Clozapine / Q000009:adverse effects*; D004311:Double-Blind Method; D004802:Eosinophilia / Q000139:chemically induced / Q000453:epidemiology*; D005260:Female; D006220:Haloperidol / Q000009:adverse effects; D006801:Humans; D015994:Incidence; D008297:Male; D009503:Neutropenia / Q000139:chemically induced / Q000453:epidemiology*; D011336:Probability; D012189:Retrospective Studies; D012559:Schizophrenia / Q000188:drug therapy
D003024:Clozapine; D006220:Haloperidol