1. ASSESSMENT OF GOLD NANOPARTICLE BASED CORTISOL STRIPS TO ASSIST CATHETERISATION DURING BILATERAL ADRENAL VEIN SAMPLING: A ROYAL NORTH SHORE PERSPECTIVE.
M Ridgwell1 C Wood1 D Tanaka1 Dr B Cooper2 Dr A Mather2 Dr R Maher3
Pathology North Endocrine Laboratory, Royal North Shore Hospital, Sydney, NSW, Australia
1Pathology North, Sydney, Australia
2 Department of Renal Medicine, Royal North Shore Hospital, Sydney, Australia
3 Department of Radiology, Royal North Shore Hospital, Sydney, Australia
This is a template for Kolling posters designed for 4 A2 sheets
(840x120cm).
Sample data taken from Anne Nelson.
Vic Danis 24/9/98
INTRODUCTION
Figure 1- Adrenal vein anatomy, with path of catheter placement during AVS[2]
Figure 2 (Patient A) – Successful right and left adrenal vein catheter placement
Routine post procedural analysis.
Confirmatory cortisol analysis of collected samples are then performed in the laboratory on the Siemens Immulite 2000 analyser, to determine a formal quantitave cortisol concentration, and the success of the AVS procedure.
A cortisol ratio of 2:1 (adrenal vein/peripheral blood) is used to indicate adequate catheterisation, which should be achieved in both right and left adrenal veins for the AVS procedure to be considered a success.
Adrenal vein sampling (AVS) is the reference procedure to distinguish between surgically curable unilateral, and bilateral adrenal disease. While accurate catheter placement is essential for this procedure, targeting the right adrenal vein can prove extremely challenging for interventional radiologists. Failure to catheterise successfully leads to costly repeat procedures at increased risk to the patient. Anatomical variations of the left adrenal vein can also prove to be challenging (Figure 1).
Cortisol estimations are performed to assess the adequacy of catheterisation in the AVS procedure. Post procedural analysis of cortisol was the standard approach, hence the adequacy of catheterisation was unknown while the procedure took place.
The “Quick Cortisol Kit” (QCK - Trust Medical Co., Ltd.) can provide an intra-procedural, semi-quantitative cortisol concentration which may assist critical decision making of accurate catheter placement, therefore potentially increasing the success rate of AVS procedures.
The aim of this study was to assess the clinical suitability of the QCK, and any changes in rate of successful catheterisation is observed.
RESULTS
Figure 3- Decreasing intensity of test line with increasing cortisol concentrations.
A review of AVS procedures performed between November 2011 and January 2016, prior to implementation of QCK indicated a success rate of 81% (N=60, 11 failed procedures due to poor catheterisation).
Despite small test numbers since January 2016 (N=9), cortisol strips confirmed adequate surgical catheterisation on four occasions (4/9); and allowed better positioning on 4 occasions (4/9), recovering from poor initial catheter placement. Post procedural interpretation of AVS cortisol/aldosterone ratios suggested 4 patients were affected by bilateral adrenal hyperplasia; 3 by right sided aldosterone secreting tumour; and 1 by left sided tumour. Of the 9 procedures performed, 1 AVS was only partially successful with a repeat AVS procedure advised.
Control line
Test line
138
276
552
828
1380
2069
2483
3311
4139
5518
CORTISOL nmol/L
Figure 4 (patient B) – Unsuccessful right adrenal vein catheter placement
Quick Cortisol Kit
The QCK, allows rapid determination of cortisol concentrations by employing competitive binding between the patient cortisol and gold nanoparticle labelled cortisol. The intensity of colour formation is used to assess the concentration of cortisol, which is inversely related at the test line. (Figure 3).
Figure 5 (patient C) – Adjustment of right adrenal vein catheter position after cortisol strip indicated unsuccessful catheterisation.
CONCLUSION
Cortisol strips have aided or confirmed accurate catheter placement in 8 of 9 AVS procedures leading to a success rate of 89%. Indeed without the aid of the intraoperative cortisol strips this success rate most probably would have fallen to 44% during this period.
The cortisol strips are easy to use, and are able to provide cortisol estimations quickly at the point of care, potentially providing a valuable tool to improve catheterization during AVS procedures and therefore increasing the success rate of AVS procedures, to the benefit of patients and health care centres.
METHOD
Intraoperative cortisol analysis.
Prior to drawing of adrenal vein bloods, a 1ml reference sample is collected from catheters placed in the inferior vena cava (IVC/peripheral sample); and the left and right adrenal veins. These reference samples are then spun at 5200g (10000 rpm) for 1 minute and 100µl of each sample is placed into the sample well of the QCK.
Development of the test line takes between 3-5 minutes, after which a semi-quantitative determination of cortisol concentration can be made. The suitability of catheter placement for each sample (Figures 2 and 4); can then be estimated with adjustments possible if required (Figure 5). Reference samples from adjusted catheter positions may then be collected and cortisol concentration re-determined, until a satisfactory catheter position is indicated (Figure 6).
Figure 6 (patient C) - Unsuccessful initial right adrenal vein catheter placement, with catheter adjustments until satisfactory.
References
Yoneda T, Karashima S, Kometani M, Usukura M, Demura M, Sanada J et al. Impact of New Quick Gold Nanoparticle-Based Cortisol Assay During Adrenal Vein Sampling for Primary Aldosteronism. J Clin Endocrinol Metab Jun;101(6):
Silvia Monticone, MD, Andrea Viola, MD, Denis Rossato, MD, Prof Franco Veglio, MD, Prof Martin Reincke, MD, Prof Celso Gomez-Sanchez, MD. Adrenal vein sampling in primary aldosteronism: towards a standardised protocol. The Lancet Diabetes & Endocrinology. Volume 3, Issue 4, April 2015, Pages 296–303
Cortisol nmol/L Immulite 2000
444
8910
452
408
1030