Ultrasound-Guided Treatment of Cystic Echinococcosis in the Spleen

Introduction

Cystic Echinococcosis (CE) is caused by the cestode Echinococccus (E.) granulosus sensu lato (s. l.). CE is endemic in parts of Africa, the Middle East, Asia and Latin America. The primary sites of CE are the liver (70 %) and lungs (20 %), but other sites including the spleen may also be infested by CE. The occurrence of CE in the spleen is rare, varying between 0.9–8 % in the literature (Akhan O et al. Semin Ultrasound CT MR 2007; 28(1): 28–34).

Diagnosis of CE is based on clinical findings, imaging and serology. Ultrasound is the basis of the imaging in the abdomen. The diagnosis is confirmed by microscopy of cyst material and by measuring antibodies against echinococcal species (Brunetti E et al. Acta Tropica 2010; 114: 1–16).

Treatment of CE can be medical with benzimidazoles, surgical, by PAIR (puncture, aspiration, injection, re-aspiration) or by a combination of these interventions (Brunetti E et al. Acta Tropica 2010; 114: 1–16 and Brunetti E et al. WHO; 2001; Available from: http://whqlibdoc.who.int/hq/2001/who_cds_csr_aph_2001.6.pdf).

The PAIR technique was developed for the treatment of intra-abdominal presentations of CE. It is a minimally invasive therapeutic option that replaces surgery. In the literature PAIR is most often used for CE in the liver, whereas CE in the spleen is often treated by partial or total splenectomy (Culafic DM et al. Scand J Gastroenterol 2010; 45(2): 186–90). Echinococcal cysts are classified in 6 stages according to their sonographic appearance (CL-CE5). Stage CE1 and CE2 are considered active stages, CE3 is considered intermediate and stages CE4 and CE5 are considered inactive. Stage CE3 is subdivided into 3a and 3b, where 3b is predominantly solid with daughter cysts. In the current guidelines by Brunetti et al., PAIR is only recommended for stages CE1 and CE3a, which are predominantly cystic. However, it is also stated that PAIR can be used in inoperable patients or patients who refuse surgery (Brunetti E et al. Acta Tropica 2010; 114:1–16 and Stojkovic M et al. PLoS Negl Trop Dis 6(10): e1880).

We describe a case of ultrasound-guided PAIR treatment in a patient suffering from isolated splenic CE who refused to undergo surgery.