Spot urine 5-HIAA creatinine ratio is comparable to 24hr urine collection for diagnosis of carcinoid syndrome

#4338

Introduction: Carcinoid syndrome (CS) constitutes up to 20% of functional neuroendocrine neoplasms and can lead to carcinoid crisis (CC), a potentially fatal complication during invasive procedures. Urine 5-hydroxyindoleacetic acid (5HIAA) is the preferred diagnostic biomarker for CS and prognostic marker for CC. 5HIAA is collected over 24-hours with strict dietary restriction for the 2 days prior as well as the day of the collection. False positive and negative results can occur due to under and over-collection. Patient inconvenience also contributes to the low request rate of this test.

Aim(s): To validate spot urine 5HIAA creatinine ratio (HCR) cut-offs against the gold standard 24 hr urine collection (24HIAA) in adult subjects for the diagnosis of CS.

Materials and methods: A retrospective study was conducted using HIAA and creatinine results from 24 hr urine samples collected between 2019 and 2023. HCR was correlated with diagnosis.

Conference:

Presenting Author: Kong G

Authors: Chiang C, Gamage I, Del Olmo-Garcia M, Pasanen L, Wong H,

Keywords: carcinoid syndrome, carcinoid crisis, urine 5-HIAA, biomarker,