Hydatid cyst disease is caused by E. Granulosus and less frequently with E. Multilocularis (1, 2). Tunisia is an endemic country of liver hydatid cyst (1). Although commonly considered "benign," this disease continues to have a devastating impact on people's health due to its potentially serious complications, especially the rupture. Three types of ruptures were described: "contained rupture" when the ruptured cyst remains surrounded and contained by the adjacent hepatic parenchyma, "communicating rupture" with bile or vascular duct, and the "direct or free rupture" in the peritoneal cavity (3, 4). Intraperitoneal Cystic rupture is a rare complication of hydatid disease and occurs in 1–16% of reported cases (2, 5, 6). This result corroborates with the current series with a prevalence estimated at 2.4%. Intraperitoneal cyst rupture can take place spontaneously and may be explained by intra-cystic pressure increase (7). It may also occur during intra-operative manipulation due to an accidental injury or by an abdominal trauma (8, 9). Three factors were incriminated in intraperitoneal cyst rupture: The young age of patients, as shown in this series (mean age 38 years), the increase in cyst diameter above 10 cm, and the superficial location unprotected by liver tissue (4, 9, 10). There are two distinct forms of Hydatid cyst rupture, the small cracking, which is the most common form, usually induced by minimal neglected trauma, and the large authentic rupture, which is often caused by severe abdominal trauma (7). The minor cracking may cause a cutaneous allergic reaction in 16–25% of cases, and the small hydatid liquid spilled in the peritoneal cavity may either encyst or evolve to a military hydatid form. The large rupture is rare and may cause either an acute form leading to immediate fatal anaphylaxis shock in approximately 1.4% of cases (9) or a severe allergic reaction such as dyspnea, syncope, and circulatory collapse in 1–12.5% of cases (11). In our study, severe allergic reactions were reported in 6,6%.
The clinical features vary greatly, from an utterly asymptomatic form discovered late after secondary peritoneal hydatidosis to the authentic anaphylactic shock, a patient life-threatening (8). Either way, the nonspecific clinical presentation should not cause a diagnosis delay, which may be a risk factor for a poor prognosis (3, 12). The most frequent symptom is a sharp pain in the right upper abdominal quadrant associated with nausea and vomiting (9). However, peritoneal symptoms may be the first developed and can be more severe if bile leakage occurs or the cyst is infected (13, 14). Clinical examination typically reveals tenderness in the right upper abdominal quadrant, and diffuse abdominal tenderness may be objectified. In the current series, five patients had diffuse abdominal tenderness.
Ultrasound is the examination of choice (1). It allows detection of the cysts and precise staging according to Gharbi classification (15) with a sensitivity of 85% (9). It also allows suspecting cyst rupture by showing a floating membrane with intraperitoneal fluid (7, 10). However, CT with a sensitivity of 100% and high-resolution multiplanar reconstruction images is a powerful tool that provides an accurate assessment of the cyst, location, vascular and biliary connexions and detects any other concomitant cysts in the abdomen (1, 3, 13). It confirms rupture by showing a collapsed cyst wall with a reduced cyst size compared to old CT findings, a detached membrane, a wall discontinuity, or daughter cysts and fluid in the peritoneal cavity (7). In our series, the CT scan allowed establishing the diagnosis in all cases. However, its main constraining factor remains the patient's hemodynamic stability.
The patient's prompt management must begin in the emergency room. Close monitoring associated with compulsory intensive care measures, the use of vasoactive drugs if needed, antihistamine medication, and corticosteroids are the first rescue measures to be taken in the emergency room (8). Urgent surgery is the basis of treatment. It has two basic goals: First, to treat the primary liver hydatid cyst, and secondary, correct its complication to prevent local and peritoneal recurrences (4, 16). Approaches of the primary liver cyst's surgical treatment can be divided into the unroofing procedure, a conservative modality, and radical methods that include pericystectomy, pericystoresection, and hepatectomy (1). In the emergency context, conservative modality seems to be the choice method since it did not require high surgical skills, it is associated with low bleeding risk and shortens the operative time (14, 17). Moreover, the unroofing prevent the morbidity of more invasive methods that would be less tolerable, especially by a patient already weakened by anaphylaxis. Our results favor this technique with a zero mortality rate and low specific post-operative morbidity (6.66%). The large volume intraoperative lavage is the second step of surgical treatment (5). Hypertonic saline solution (3%-30%) is the widely used solution for this purpose (10, 16, 17). Some authors choose not to use hypertonic saline solution due to its possible complications, such as hypernatremia (1, 18). The scolicidal solution was safely used in all cases in our study. Other experimental studies even advocate the use of povidone-iodine as a solution with a better scolicid potential (5, 16). This surgical step aims to end the peritoneum and hydatid antigens contact, causing the allergic reaction and removing all cyst contents, especially the protoscolex, source of late disseminated recurrence (4, 8, 9). In case of large cysts greater than 10.5 cm or with bilious content or in the presence of clinical (cholestatic jaundice), biological (biological cholestasis) or radiological (bile ducts dilatation) signs of associated rupture into the bile ducts, intraoperative cholangiogram is indicated, and fistula treatment is required (19–21). Anthelmintic treatment based on albendazole (15 mg/kg/day) should be initiated as soon as possible after surgery (8). There is no consensus on the treatment's duration. Besides, several experimental studies have demonstrated the superiority of the combination of chemotherapy and cytokines over albendazole alone (22). In our center, a medical habit of maintaining Albendazole treatment for at least 12 months was respected in all patients. The effectiveness of this procedure is confirmed by none secondary peritoneal hydatidosis was observed in our series. Considering recurrence risk, correlated to insufficient peritoneal lavage or medical treatment (6), patients with treated hydatid cysts should have appropriate follow up based on hydatid serology (indirect hemagglutination test) associated with abdominal ultrasound every 3 to 6 months. We estimate that those two methods allow recurrence early checking and treatment. The CT scan may be a part of the subsequent investigations in doubtful cases only to reduce patients' exposure to radiation. Beyrouti et al. reported a recurrence rate of 6,7%, and the higher rate at 14% was reported by Sosuer et al. (1). In the present series, no recurrence case was detected with a median follow-up period of 19 months.