Secondary Peritoneal Hydatidosis: A Radio-pathological Correlation of Rare Presentation

1. Junior Resident, Department of Pathology, Jawaharlal Nehru Medical College, Sawangi Meghe, Wardha, Maharashtra, India. 2. Junior Resident, Department of Pathology, Jawaharlal Nehru Medical College, Sawangi Meghe, Wardha, Maharashtra, India.

Abstract

A 36-year-old female patient was referred from a secondary rural hospital to the outpatient department, presented with a gradually increasing lump in the abdomen associated with dull aching pain and discomfort, along with weight loss since three months. Physical examination revealed a palpable diffuse mass of about 14×14 centimeters in the epigastric region extending to the right hypochondrium as well as a mild shift towards the left hypochondrium. Routine haematological and biochemical parameters, including complete blood count, liver function tests, and renal function tests, were normal. Chest radiography was normal.

Serology and imaging studies were performed. Abdominal ultrasonography showed a large hypoechoic cystic mass. Computed tomography also revealed a hypodense cystic lesion with well-defined margins, multiple daughter cysts with internal septations intraabdominally measuring 12×10 cm, and a well-circumscribed unilocular cyst in the right hepatic lobe measuring 4×3.5 cm (Table/Fig 1). The differential diagnosis based on clinical and radiological findings included simple hepatic cysts, amoebic liver abscess, choledochal cyst, Caroli’s disease, fasciola hepatica infection, and hydatid cyst of the liver and peritoneum.

Based on clinical and radiological evaluation for this case, Fine Needle Aspiration Cytology (FNAC) was planned to rule out the differentials. FNAC was carried out. On aspiration, 5 mL of clear, watery fluid was aspirated. Air-dried smears were prepared from centrifuged deposits of the fluid, which were stained with May-Grunwald-Giemsa (MGG) stain. Microscopic examination of the aspirated fluid smear showed detached refractile hooklets in the background of necrotic debris with an inflammatory cell reaction consisting of neutrophils and hemosiderin-laden macrophages. Thus, a cytological diagnosis of a hydatid cyst was made (Table/Fig 2). Later serology too was done which revealed that serologic agglutination tests for echinococcus antibody were positive with a titer of 1:528.

After the investigation, a surgical approach was planned by exploratory laparotomy. Tablet Albendazole was given preoperatively for 10 days, and the patient was advised to visit for surgery after 10 days. But, the patient visited within five days with severe abdominal pain and discomfort. An emergency laparotomy was done. The procedure consisted of peritoneal evacuation with partial pericystectomy of concomitant hepatic hydatid cysts. The punctured sites of the cysts were covered with surgical mop immersed in a hypertonic saline solution to produce a scolicidal effect. The intra-abdominal cysts were first aspirated, followed by initial decompression and evacuation with a trocar. The further cystic cavities were refilled with 20% hypertonic saline to sterilise the exposed areas. The peritoneal cysts, after unroofing, were left open.

In this case of concomitant hepatic hydatid cysts, the openings of the pericysts were sutured and filled with omentum. The remaining cavities were inspected for bile leakage, and a drainage tube was placed. In this case, 20-24 intra-abdominal cysts, as well as a single ruptured hepatic cyst, were evacuated, followed by unroofing and left open with abdominal drainage. Albendazole was prescribed orally postoperatively (600 mg) in two divided doses for two months. After seven days, the drain was removed, and the patient was discharged advised for follow-up every three months.

The excised ruptured specimens of liver and peritoneum were sent for histopathological examination. The gross examination of the excised peritoneal cysts showed a single, cut-open, yellowish structure measuring approximately 13×10 cm with multiple small daughter cysts embedded, while the hepatic cysts were present in multiple small fragments of the cyst (Table/Fig 3)a-c.

Microscopic examination of grossed and sectioned tissue confirmed the diagnosis of peritoneal hydatidosis secondary to hepatic hydatid cysts. The section showed an acellular eosinophilic lamellated membrane surrounded by areas of fibrosis and chronic inflammatory cell infiltrates, including lymphocytes, eosinophils, and histiocytes. The smear also showed one hydatid protoscolex containing a sucker with micronuclei and hooklets (Table/Fig 4)a,b. Echinococcus is a zoonotic infection caused by a parasite in its larval stage, by tapeworm species of the genus Echinococcus. It exists in two forms: the cystic form is caused by the larval stage of Echinococcus granulosus, and the alveolar form is caused by Echinococcus multilocularis. This infection is transmitted to humans from animals by fecal-oral route. According to the World Health Organisation (WHO), the incidence is 50 per 100,000 population per year, especially in endemic areas (1).

Structurally, hydatid cysts have three layers: a) Pericyst or outer layer consisting of fibroblasts, eosinophils, and foreign body giant cells, thus forming a protective layer; b) Ectocyst or middle layer of a lamellated membrane, which is acellular and allows passage of nutrients; c) Endocyst or innermost germinal layer where scolices are formed from the outgrowth of this layer (1).

Hydatid cysts can involve any part of the body, but the liver is commonly affected, approximately 70%, followed by the lungs (27%), peritoneum (13%), brain (1-2%), bone (1-4%), kidney (1-3%), and spleen. The common clinical presentation is a gradually increasing lump in the abdomen associated with dull aching pain, discomfort, weight loss, and anorexia (2),(3),(4),(5). Diagnosing hydatid disease can be challenging. Serology and imaging are the main diagnostic modalities. Ultrasonography is preferred as the first line for screening, but computed tomography accurately defines its morphology (2),(3),(6). FNAC too played a role for initial work-up, but along with histopathological correlation, it only confirms the diagnosis of Echinococcosis, especially in cases of dissemination or concomitant involvement of other organs.

In the present case, it is depicted that both hydatid cysts of the liver and peritoneum coexist at the same time. Peritoneal dissemination may have occurred as a consequence of previous abdominal trauma. A combination of pre- and postoperatively albendazole therapy followed by a surgical approach was a mainstay for treatment in this case. Critical care is required intraoperatively too as spillage of cyst contents can lead to dissemination to other organs, anaphylaxis, and even death. Therefore, peritoneal hydatidosis must be included in the differential diagnosis of sonographically diagnosed intra-abdominal benign and neoplastic lesions.

Abdominal lump, Daughter cyst, Hepatic hydatid cyst

DOI and Others

Doi: 10.7860/JCDR/2024/73192.20236

Date of Submission: May 30, 2024
Date of Peer Review: Jun 06, 2024
Date of Acceptance: Jun 12, 2024
Date of Publishing: Nov 01, 2024

AUTHOR DECLARATION:
• Financial or Other Competing Interests: None
• Was informed consent obtained from the subjects involved in the study? Yes
• For any images presented appropriate consent has been obtained from the subjects. Yes

PLAGIARISM CHECKING METHODS:
• Plagiarism X-checker: Jun 03, 2024
• Manual Googling: Jun 07, 2024
• iThenticate Software: Jun 10, 2024 (8%)

ETYMOLOGY: Author Origin

EMENDATIONS: 4