• oesophageal varices
• platelet count
• spleen diameter ratio

We read with great interest the article by Giannini et al on platelet count/spleen diameter ratio or platelets alone as predictors of oesophageal varices (Gut 2003;52:1200–5).

As the incidence of chronic liver diseases is growing, we are convinced that the development of non-invasive predictive tools to identify cirrhotic patients with oesophageal varices is of major interest. Several markers have been studied, and among them platelet count is commonly reported to be a good predictor of oesophageal varices. However, in the eight studies already published,^1–8 their discriminative power was moderate, with areas under the receiver operating curve (ROC) of 0.70 or less for platelets alone⁴ and for indexes combining platelets with other markers.^1,4,5 Most of these studies included heterogeneous groups of patients, with compensated and decompensated cirrhosis.

In our unit, we performed prospectively platelet count and screening upper oesogastroduodenoscopy on the same day in 41 patients with compensated cirrhosis and confirmed the moderate value of platelet count alone (AUROC = 0.70 (0.07); Thabut, data not shown). The major drawback of platelet count is that it can depend on factors other than portal hypertension in cirrhotic patients. To avoid this bias, Giannini et al developed an index based on platelet count/spleen diameter ratio and found far better results than previous studies, with a c index (equivalent to the area under the ROC) of 0.92 for patients with compensated liver cirrhosis. However, we were surprised to see that the use of platelets/spleen diameter ratio did not add significant discrimination to platelet count alone (c index of 0.92 v 0.88) in their population. …