The main purpose of this Manual is to provide useful guidelines for the selection of pathology tests and to facilitate interpretation of results.
Contains a comprehensive listing of all genes from the Human Gene Nomenclature Committee (HGNC) database alongside laboratories and tests available in the country.
A manual for the process of macroscopic dissection in Anatomical Pathology laboratories.
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Keywords: C1q esterase inhibitor assay, complement C1 esterase inhibitor, C1-Inhibitor, C1 Inhibitor
Immunochemical assay: 5 mL blood in plain tube.
Functional assay: 5 mL blood in EDTA tube.
The specimen should be placed on melting ice and transported immediately to the laboratory.
Functional and immunochemical assay.
Immunochemical: 0.25-0.42 g/L
Functional: consult pathologist.
Levels of C3 and C4 should be determined before this test is requested; see Complement components C3 and C4.
Investigation of angioedema: C1 inhibitor levels are unlikely to be reduced if C4 is normal.
Diagnosis of hereditary angioedema due to C1 inhibitor deficiency, acquired C1 inhibitor deficiency in malignancy and SLE.
Genetic and acquired forms of C1 inhibitor deficiency are distinguished by family history and on clinical grounds.
In genetic deficiency, 85% of kindreds have low functional and immunochemical levels; 15% of kindreds have low functional levels with normal or high immunochemical levels. Levels may rise with danazol treatment.
Walport MJ. N Engl J Med 2001; 344: 1058-1066.
Australasian Society of Clinical Immunology and Allergy (ASCIA). Position Paper on Hereditary Angioedema: August 2012. Sydney: ASCIA, 2012.
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The RCPA is the leading organisation representing Pathologists and Senior Scientists in Australasia.
Its mission is to train and support pathologists and senior scientists and to improve the use of pathology testing to achieve better healthcare.
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