To the editor: We are grateful to Virgilio and colleagues for their interest in our work [1] about peritoneal echinococcosis (PE), and for the two interesting topics they raise in their letter. Preoperative autologous blood donation (PABD) aims to provide a supply of safe blood for patients undergoing surgery who may need blood transfusion; at the same time, it helps increase the patient’s total red blood cell mass due to the PABD-induced stimulation of erythropoiesis before scheduled elective surgery [2]. It is well known that PABD is contraindicated in cases of bacterial infection, even though nothing in the international recommendations about hydatid infection as a contraindication of PABD has been reported. However, the only case of PABD in hydatid cyst (HC) surgery was reported by Roussel et al. [3]. In their article, the authors agreed that PABD has a theoretical risk of dissemination of the hydatid disease, but they were forced to use it exceptionally in this case because of the lack of available blood of the patient’s type and because of the high risk of a large hepatic cyst rupture. Surgical management of PE should be performed safely to avoid intraoperative morbidity or mortality. To avoid hemorrhagic complications when cysts are attached to major vessels, conservative treatment involving drainage and wide deroofing may be recommended. In our university hospital, management of liver HC is based mainly on the use of conservative approaches [4] with very low risk of bleeding. Thus, we do not have any experience with PABD in hydatid cyst surgery. Because there is a lack of scientific evidence regarding its safety in the management of HC, and because of the unacceptable theoretical risk of infectious dissemination after PABD, we think that this technique should be avoided in patients with HC whatever the location. It is widely assumed that the aim of scolicidal agent injection into an unopened HC is to reduce the risk of spillage into the peritoneal cavity and thus to avoid recurrence. Cyst fluid contains thousands of protoscoleces, and each one has the potential to grow into a new HC. In our experience, we routinely use hydrogen peroxide as a scolicidal agent [4] because oxygen peroxide 3 % has proved to be more effective than 20 % saline in many in vitro studies [5]. Moreover, with 20 % saline, many cases of sclerosing cholangitis and hypernatremia have been reported. Hypertonic saline 33 %, used by Virgilio and colleagues, is a higher concentration that can also lead to, at least, cholangitis and hypernatremia. We do not encourage the use of hypertonic saline as scolicidal agent in hydatid cyst surgery without any comparative study of its safety. According to the literature and our experience, PE should be managed in specialized centers to avoid recurrences and surgical morbidity. The only warrant of peritoneal hydatid cyst surgery success is the choice of the safest surgical approach. In our opinion, PABD should not be used, and because hydrogen peroxide is more effective M. A. Majbar F. Sabbah M. Raiss A. Hrora M. Ahallat Clinique Chirurgicale C, Ibn Sina Hospital, 17 Avenue Ibn Rochd, 10000 Rabat, Morocco