Sudden late onset of clozapine-induced agranulocytosis.

Austin State Hospital, Texas Department of Mental Health and Mental Retardation, Austin, USA.
Annals of Pharmacotherapy (Impact Factor: 2.92). 07/2002; 36(6):1012-5. DOI: 10.1345/aph.1A417
Source: PubMed

ABSTRACT To report a patient who suddenly developed agranulocytosis after long-term clozapine therapy.
A 41-year-old white man suddenly developed agranulocytosis after 89 months of nearly continuous clozapine therapy. During this time, which included the addition of risperidone to the treatment regimen, his white blood cell (WBC) and granulocyte counts remained stable. One week after having stable hematologic counts, the patient suddenly developed agranulocytosis. WBC and granulocyte counts returned to baseline shortly after discontinuation of all medications and administration of sargramostim.
The main factor limiting the use of clozapine as a first-line agent in mentally ill patients is the risk of agranulocytosis. Although the greatest risk of developing this adverse reaction is during the initial 6-month exposure, clozapine-induced agranulocytosis continues to pose a risk after years of exposure. Current product labeling requires weekly WBC and granulocyte monitoring for the first 6 months of treatment with clozapine, which may be decreased to biweekly monitoring after 6 months. Based on the sudden and late onset of agranulocytosis in our patient, clinicians may consider opting for weekly monitoring of hematologic function for patients on long-term clozapine therapy. The likelihood that clozapine was the cause of the agranulocytosis was rated possible according to the Naranjo probability scale.
Clinicians must remain vigilant to trends in WBC and granulocyte counts and may wish to consider weekly hematologic monitoring regardless of duration of clozapine therapy. Patient and treatment system compliance with the registries' protocol regarding WBC monitoring is instrumental in reducing morbidity and mortality rates associated with clozapine use.

  • Journal of clinical psychopharmacology 12/2011; 31(6):780-1. DOI:10.1097/JCP.0b013e318234eec2 · 5.09 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Infants with biliary atresia undergoing living donor liver transplantation (LDLT) are at increased risk of portal vein (PV) complications because of their smaller vascular caliber and sclerosis because of previous Kasai portoenterostomy and recurrent cholangitis. Of 154 children who underwent transplantation between November 2005 and January 2011, 34 with biliary atresia received a transplant while younger than 1 year. Six patients underwent PV reconstruction with an interposition vein graft, and the others underwent the branch patch technique. The clinical characteristics of those who underwent the interposition reconstruction or the branch patch technique were compared, and the PV complications were assessed. Portal vein complications occurred in 5 patients (14.7%) in the branch patch group. There were 4 patient deaths, and all of them had received branch patch reconstruction. The branch patch reconstruction cases with a sclerotic small caliber (<4 mm) determined by using preoperative ultrasonography showed a significantly high mortality rate (44.4%). All patients with interposition vein graft reconstruction are still alive with excellent graft function without anticoagulation therapy. The interposition vein graft appears to be a feasible option with better graft survival and less PV complications when performing LDLT for biliary atresia in infants younger than 1.
    Journal of Pediatric Surgery 03/2012; 47(3):523-7. DOI:10.1016/j.jpedsurg.2011.09.036 · 1.31 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Clozapine is a second-generation antipsychotic agent from the benzodiazepine group indicated for treatment-resistant schizophrenia and other psychotic conditions. Using clozapine earlier on once a case appears to be refractory limits both social and personal morbidity of chronic psychosis. However treatment with second-generation antipsychotics is often complicated by adverse effects. We present a case of a 33-year-old Caucasian woman with a 25-year history of refractory psychotic mania after switching to a 2-year clozapine therapy. She presented clozapine-induced absolute neutropenia, agranulocytosis, which were complicated by Streptococcus pneumonia and sepsis. Clozapine-induced thromboembolism of the common femoral and right proximal iliac vein, as well as allergic vasculitis, was diagnosed. She achieved full remission on granulocyte-colony stimulating factor and specific antibiotic treatment. Early detection of severe clozapine-induced absolute neutropenia and agranulocytosis enabled the effective treatment of two among its most severe complications. Additional evidence to the previously reported possible causal relation between clozapine and venous thromboembolism is offered. Finally, clozapine-induced allergic vasculitis is confirmed as a late adverse effect of clozapine therapy.


1 Download
Available from