We thank Dr. Thabut et al. for their interesting comments following the publication of our study that compares Psychometric Hepatic Encephalopathy Score (PHES) and Critical Flicker Frequency (CFF) to predict post-TIPS encephalopathy in patients with cirrhosis. Since specific normative data for PHES are not yet available in France, we used the Spanish algorithm because it was validated in Latin countries (such as France)[2, 3] and also because Toulouse is only 150 km north of Spain. Using the same algorithm, Dr. Thabut et al. found that minimal hepatic encephalopathy (MHE) is underdiagnosed by PHES in cirrhosis patients in northern France. They also concluded that PHES should be validated in each country before its use for MHE diagnosis. However, the reliability of the test in a specific patient is not warranted by such validation. Actually, not all patients originate from their residing country. For example, should we use in France the Spanish algorithm for a patient born and raised in Spain? A Japanese algorithm for Japanese patients? Then how long after their settling in a country should we switch to the specific algorithm of that country? Actually, it will be much more difficult to have a set of different PHES specifically tailored for particular education and cultural backgrounds. On the contrary, CFF is readily available, fast to perform, and can be used for all patients independently of their education level, age, residing country, or training. Combined with our results, this confirms the advantages of CFF over PHES.
Christophe Bureau, M.D., Ph.D.
Jean-Pierre Vinel, M.D.
Service d'hepato-gastro-enterologie CHU Toulouse Hopital Purpan et Universite Paul Sabatier Toulouse, France