ASH evidence-based guidelines: is the IgG-specific anti-PF4/heparin ELISA superior to the polyspecific ELISA in the laboratory diagnosis of HIT?

@article{Cuker2009ASHEG,
  title={ASH evidence-based guidelines: is the IgG-specific anti-PF4/heparin ELISA superior to the polyspecific ELISA in the laboratory diagnosis of HIT?},
  author={Adam Cuker and Thomas L. Ortel},
  journal={Hematology. American Society of Hematology. Education Program},
  year={2009},
  pages={
          250-2
        }
}
  • A. Cuker, T. Ortel
  • Published 2009
  • Medicine
  • Hematology. American Society of Hematology. Education Program
You are asked to consult on a 76-year-old man admitted to the hospital with pneumonia and thrombocytopenia. Ten days before the current admission, he had undergone surgery to repair a small bowel obstruction. A preoperative platelet count had been normal. Following surgery, he received subcutaneous unfractionated heparin thromboprophylaxis until his discharge on post-operative day 5. In your differential diagnosis for the patient's thrombocytopenia, you consider heparin-induced thrombocytopenia… 
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Incidence of Isolated Heparin-Induced Thrombocytopenia and Risk of Thrombosis by IgG-Specific Anti-PF4/Heparin ELISA
TLDR
The improved specificity of the IgG- ELISA appears to reduce the incidence of isolated HIT which may have lower risk of subsequent thrombosis.
Pitfalls in the diagnosis of heparin‐Induced thrombocytopenia: A 6‐year experience from a reference laboratory
TLDR
The number of SRA‐negative samples was reduced from referring centers that used an immunoassay as an initial screen; however, 41% of those samples tested negative in the immunoASSay and in the SRA at the reference laboratory, suggesting the suspicion of HIT continues at a high rate.
Clinical and laboratory diagnosis of heparin-induced thrombocytopenia: an integrated approach.
  • A. Cuker
  • Medicine, Biology
    Seminars in thrombosis and hemostasis
  • 2014
TLDR
A Bayesian approach that combines the 4T score and the PF4/heparin ELISA result may be used to estimate the probability of HIT and guide clinical decision making.
Assessment of a modified 4T scoring system for heparin-induced thrombocytopenia in critically ill patients.
Novel diagnostic assays for heparin-induced thrombocytopenia.
TLDR
KKO-I and DT40-luc showed better discrimination than 2 commercially available immunoassays, are simple to perform, and hold promise for improving the specificity and feasibility of HIT laboratory testing.
The Role for Optical Density in Heparin-Induced Thrombocytopenia: A Cohort Study.
TLDR
Altering the definition of the HIT ELISA could prevent unnecessary testing and/or treatment with non-heparin-based anticoagulants in patients with possible HIT and improve diagnostic accuracy for HIT.
How I treat heparin-induced thrombocytopenia.
TLDR
This review describes not only the approach to the evaluation and management of patients with heparin-induced thrombocytopenia, but also the measures used to minimize misdiagnosis and unnecessary treatment of patients without the disease.
Heparin-induced thrombocytopenia (HIT) in 2011: an epidemic of overdiagnosis.
  • A. Cuker
  • Medicine, Biology
    Thrombosis and haemostasis
  • 2011
TLDR
Over-diagnosis of Heparin-induced thrombocytopenia is particularly rampant in the intensive care units and the post-cardiac surgery setting, where the frequency of alternative anticoagulant use outstrips the incidence of HIT by an order of magnitude or more.
Comparison of an IgG-Specific Enzyme-Linked Immunosorbent Assay Cutoff of 0.4 Versus 0.8 and 1.0 Optical Density Units for Heparin-Induced Thrombocytopenia
  • B. Ritchie, J. Connors, K. Sylvester
  • Medicine
    Clinical and applied thrombosis/hemostasis : official journal of the International Academy of Clinical and Applied Thrombosis/Hemostasis
  • 2017
TLDR
This study suggests an increased antiheparin–PF4 ELISA threshold of 0.8 or 1.0 OD units enhances specificity, PPV, and accuracy while maintaining NPV with decreased sensitivity.
Differences in the clinical course of heparin induced thrombocytopenia before and after the availability of HIT IgG class testing.
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References

SHOWING 1-10 OF 11 REFERENCES
Prospective evaluation of PF4/heparin immunoassays for the diagnosis of heparin‐induced thrombocytopenia
TLDR
Evaluation of the clinical usefulness of different antigen‐binding assays for detection of antibodies against PF4/hep complexes in a prospective study indicates that an IgG‐ELISA provides the best diagnostic information of all antigen‐ binding assays.
Laboratory testing for the antibodies that cause heparin-induced thrombocytopenia: how much class do we need?
Incidence and clinical significance of anti‐PF4/heparin antibodies of the IgG, IgM, and IgA class in 755 consecutive patient samples referred for diagnostic testing for heparin‐induced thrombocytopenia
TLDR
Detection of IgG, IgM and IgA class antibodies by PF4/heparin ELISA yields a positive test result about twice as often as does a platelet activation assay, with only a minority of the additional patients detected likely having HIT.
Heparin‐induced thrombocytopenia: a prospective study on the incidence, platelet‐activating capacity and clinical significance of antiplatelet factor 4/heparin antibodies of the IgG, IgM, and IgA classes
TLDR
Clinical correlations showed that HIPA‐negative/EIA‐positive patients did not develop thrombosis and had reasons other than HIT to explainThrombocytopenia, and the anti‐PF4/heparin EIA has high sensitivity for HIT, but only about half of EIA‐ positive patients are likely to have HIT.
What is the potential for overdiagnosis of heparin‐induced thrombocytopenia?
TLDR
There is the potential to overdiagnose HIT by ∼100% if any positive EIA is considered to “confirm” the diagnosis of HIT irrespective of the clinical scenario.
Determination of heparin–platelet factor 4–IgG antibodies improves diagnosis of heparin‐induced thrombocytopenia
TLDR
Antibody‐positive patients with HIT had significantly higher levels of IgG antibodies than those without HIT, while they did not differ concerning IgM and IgA antibodies, and Heparin–PF4–IgG antibodies can identify patients at risk of developing life‐threatening HIT.
Anti‐PF4–heparin immunoglobulin G is the major class of heparin‐induced thrombocytopenia antibody: findings of an enzyme‐linked immunofiltration assay using membrane‐bound hPF4–heparin
TLDR
The detection of anti‐hPF4–heparin IgG in all HIT sera supports the assay ofAnti‐PF4‐hepar in IgG as being a sensitive screening test for HIT, as it was detected in only 48% of SRA‐positive HITSera.
Characterization of the humoral immune response in heparin‐induced thrombocytopenia
TLDR
The class, subclass, and potency of antibodies specific for heparin:PF4 complexes formed by two groups of patients, one with severeThrombocytopenia, with or without thrombosis, and a positive serotonin release assay (SRA) are studied.
Heparin-induced thrombocytopenia.
  • T. Ortel
  • Medicine
    Seminars in hematology
  • 1998
TLDR
A 63-year-old man with coronary artery disease who has recently undergone bypass surgery presents with dyspnea; chest radiography shows a pulmonary embolism; and Heparin-induced thrombocytopenia is suspected.
This Journal feature begins with a case vignette highlighting a common clinical problem. Evidence supporting various strategies is then presented, followed by a review of formal guidelines, when they exist. The article ends with the authors' clinical recommendations. Heparin-Induced Thrombocytopenia
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