|Description||Serotonin is primarily raised in classical metastatic mid-gut carcinoid tumours. It is taken up readily by platelets or converted to 5-HIAA. Whole blood serotonin is measured and related to blood platelets.|
|Indication||Investigation of suspected carcinoid disease.|
|Additional Info||Carcinoid disease is characterised by tumours of the argentaffin cells which produce excessive amounts of serotonin. The serotonin is usually rapidly metabolised by the liver to 5-hydroxyindoleacetic acid which is excreted via the kidneys. However in mid gut tumours with liver metastases, or in foregut tumours where the serotonin drains directly into the systemic circulation, the serotonin can cause flushing, diarrhoea, wheezing and heart disease - the so called 'carcinoid syndrome'. Should be measured in conjunction with plasma 5-HIAA. Please refer to the following reference for useful information on preanalytical factors: https://www.ncbi.nlm.nih.gov/pubmed/29292526|
|Interpretation||Levels above the reference range are suggestive of carcinoid disease.
|Department||Specialist Laboratory Medicine|
|Collection Conditions||A 2nd EDTA blood sample should be sent to haematology for a full blood count. Samples for serotonin should be sent to the laboratory and frozen as soon as possible, preferably within 3 hours. Specimen reception: 'PLEASE DO NOT CENTRIFUGE ANY SEROTONIN SAMPLES'. Samples must sent to Block 46 (Specialist Laboratory Medicine) frozen.|
|Min. Vol||1 mL|
|Ref. Range (Male)||<7.0 nmol/10^9 platelets|
|Ref. Range (Female)||<7.0 nmol/10^9 platelets|
|Ref. Range (Paed)|| |
|Ref. Range Notes||Lower levels may be found in elderly subjects and in patients taking SSRIs|
|IP Acute TAT||- Contact Laboratory|
|IP Routine TAT||20 days|
|GP Acute TAT||- Contact Laboratory|
|GP Routine TAT||20 days|
Originally edited by : . Review due on 17/09/2019 16:35:03. Published By Robert Barski on 17/09/2018 16:35:03.