Clinical trial NCT02790567: Rapid Diagnosis of Heparin-Induced Thrombocytopenia in Surgical Critically Ill Patients
Official title: Evaluation of Automated Immunoassay, Particle Gel Immunoassay and Pretest Scoring Systems (4Ts and HEP Scores) in the Diagnosis of Heparin-induced Thrombocytopenia in Surgical Critically Ill Patients
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Heparin-induced Thrombocytopenia (HIT)
Keywords: diagnostic performance
heparin-induced thrombocytopenia
rapid immunological diagnostic method
immunoassay
pretest scoring systems
4Ts score
HEP score
Lead sponsor: Centre Hospitalier Universitaire de Besancon
Sponsor class: OTHER
First posted: 2016-06-06
Enrollment: 120
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients admitted in our surgical intensive care unit (ICU) during the study period will be elligible if the diagnosis of HIT is supected by the attending physician. The diagnosis of the HIT will be suspected in the presence of at least one of the following criteria in a patient receiving an heparin therapy: (1) a thrombocytopenia \< 100 G/l or a decrease of the blood platelet count \> 40%, (2) a thrombocytopenia between the 5th and the 8th of the heparin therapy, (3)an arterial or a venous thrombosis in a patient receiving heparin, (4)the failure of a treatment of a thrombosis with heparin. These criteria are described in the French guidelines.

Brief summary: The early diagnosis of heparin-induced thrombocytopenia is particularly difficult in surgical critically ill patients. If the use of rapid immunological diagnostic methods and pretest scoring systems has been proposed in the medical intensive care unit (ICU), none of these methods have been specifically evaluated in the diagnosis of HIT in surgical patients.

Detailed description: Heparin-induced thrombocytopenia (HIT) is of concern in critically ill patients, given the high prevalence of heparin use. The diagnosis of HIT in surgical intensive care unit (ICU) is problematic due to the lack of reliable diagnostic method. No gold standard currently exists and the definitive diagnosis is mainly based on the detection of heparin-dependent platelet-activating antibodies by ELISA method, on the platelet serotonin release assay (SRA) and on the changes of the blood platelet count after the discontinuation of heparin therapy. As a result, no early definitive diagnosis could be done. This could expose patients to thrombotic complications related to the HIT or hemorrhagic complications related to the alternative anticoagulant prescribed. This complications can threaten the prognosis of these patients. Particle gel immunoassay and automated immunoassay has been proposed for the early diagnosis of HIT in medical critically ill and non-critically ill patients. Many authors suggest that the accuracy of these immunological methods for the diagnosis of HIT could be altered in surgical patients, but these tests has never been specifically evaluated in this population. The 4Ts and the HIT Expert Probability (HEP) score systems sound interesting for the diagnosis of HIT. These clinicobiological scores can be easily used by non-expert clinicians, but have also never been evaluated in the surgical ICU.

Eligibility criteria: Inclusion Criteria:

* Age \> 18 years old
* Diagnosis of HIT suspected
* Admitted in our surgical intensive care unit during the study period

Exclusion Criteria:

* Age \< 18 years old
* Pregnancy and/or breast feeding
* Fondaparinux anticoagulation
* Withdrawal of consent

Primary outcomes:
measure: Sensibility, specificity, positive and negative predictive values of HEP score for the diagnosis of heparin-induced thrombocytopenia (HIT)
timeFrame: during the ICU stay, i.e an average time of 10 days
Secondary outcomes:
measure: Sensibility, specificity, positive and negative predictive values of the 4Ts score for the diagnosis of heparin-induced thrombocytopenia (HIT)
timeFrame: during the ICU stay, i.e an average time of 10 days
measure: Sensibility, specificity, positive and negative predictive value of the particul gel immunoassay ID-PaGia test for the diagnosis of heparin-induced thrombocytopenia (HIT)
timeFrame: during the ICU stay, i.e an average time of 10 days
measure: Sensibility, specificity, positive and negative predictive values of the automated immunoassay HemosIL-Ab latex agglutination test for the diagnosis of heparin-induced thrombocytopenia (HIT)
timeFrame: during the ICU stay, i.e an average time of 10 days
Other outcomes:
Locations:
city: Besançon
country: France
facility: Centre Hospitalier Universitaire de Besançon
Study officials:
affiliation: Centre Hospitalier Universitaire de Besançon
name: Marc Ginet, MD
role: PRINCIPAL_INVESTIGATOR
References: