BACKGROUND

Portal hypertension is a major complication of cirrhosis that is associated with significant morbidity and mortality. The present gold-standard method to risk stratify and observe cirrhosis patients with portal hypertension is hepatic venous pressure gradient measurement or esophagogastroduodenoscopy. However, these methods are invasive, carry a risk of complications and are associated with significant patient discomfort. Therefore, non-invasive splenic parameters are of clinical interest as potential useful markers in determining the presence of portal hypertension. However, diagnostic accuracy and reproducibility remains unvalidated.
AIM

To assess the diagnostic accuracy of spleen stiffness, area and diameter in predicting the presence of portal hypertension.
METHODS

Of 50 patients with varying liver disease pathologies were prospectively recruited from the St. Mary’s Hospital Liver Unit in London; 25 with evidence of portal hypertension and 25 with no evidence of portal hypertension. Liver stiffness, spleen stiffness, spleen diameter and spleen area were measured using the Philips Affiniti 70 elastography point quantification point shear wave elastography system. The aspartate aminotransferase-to-platelet-ratio-index (APRI) score was also calculated. Performance measures, univariate and multivariate logistic regression were used to evaluate demographic, clinical and elastography variables. Interclass correlation coefficient was used to determine the reproducibility of splenic area and diameter.
RESULTS

On univariate and individual performance, platelet count [area under the receiver operating characteristic (AUROC) 0.846, P value < 0.001], spleen area (AUROC 0.828, P value = 0.002) and APRI score (AUROC 0.827, P value < 0.001) were the most accurate variables in identifying the presence of portal hypertension. On multivariate logistic regression models constructed, the combination of spleen area greater than 57.90 cm2 and platelet count less than 126 × 109 had 63.2% sensitivity and 100% specificity, 100% positive predictive value and 100% negative predictive value. An alternative combination of spleen stiffness greater than 29.99 kPa and platelet count less than 126 × 109 had 88% sensitivity, 75% specificity, 78.6% positive predictive value and 85.7% negative predictive value. An interclass correlation coefficient value of 0.98 (95%CI: 0.94-0.99, P value < 0.001) and 0.96 (95%CI: 0.91-0.99, P value < 0.001) were determined for inter-operator variability for spleen area and diameter respectively.
CONCLUSION

Spleen area, spleen stiffness and platelet count may be useful markers to assess the presence of portal hypertension in patients of various etiologies.
Key Words: Portal hypertension, Esophageal varices, Point shear wave elastography, Spleen stiffness, Spleen area, Non-invasive

Core Tip: Non-invasive splenic parameters are useful surrogate markers of portal hypertension (PH). A combination of spleen diameter, spleen area, liver stiffness and aspartate aminotransferase-to-platelet-ratio-index (APRI) score is able to predict the presence of PH. The APRI score has a similar diagnostic accuracy to combination index.