**1. Introduction**

The Echinococcosis is a zoonotic disease caused by a parasitic infection with the larval stage of the tapeworm Echinococcus genus [1]. Among the recognized species, two are of medical importance – E. granulosus and E. multilocularis – causing cystic echinococcosis (CE) and alveolar echinococcosis (AE) in humans respectively. Cystic echinococcosis is the most common form of the disease [2].

The Echinococcus can infect domestic animals, the adult tapeworms are carried by the definitive host (dogs) asymptomatically and can transmit the worms through defecation contaminating humans if ingest affected intermediate host meat (sheep, cattle, goats, and pigs). Human hydatid cyst is a health problem in some developing countries [3], this disease is usually asymptomatic for years until develop complications: such as compressive symptoms or rupture of the cyst causing anaphylactic shock. In most of the patients the symptoms are non-specific for the disease [4].

#### **2. Course of infection**

**1**

Have been reported in Ultrasound (US) surveys that the cysts may grow 1–50 mm per year or persist without changes according with [5, 6]; these cysts may spontaneously rupture or collapse and also disappear [5, 7].

The sequence of the changes during the natural history of this cysts is not well define [8], the Liver cysts appear to grow at a lower rate than the lung cysts [6]. The symptoms appear in this disease usually when the cyst compresses or ruptures into neighboring structures [6].

The diagnosis of CE is based on symptoms when they are present, Ultrasound, CT imaging techniques, and serology. The Proof of the presence of protocolises could be given by microscopic examination of the fluid and histology [9].

Source: Expert consensus for the diagnostic and treatment of cystic and alveolar echinococcosis in humans, 2010 [5].

The ultrasound (US) examination is the basis for the diagnosis and the WHO classification of the disease in abdominal locations of the cysts, this technique could visualize cysts in other locations no suspected, such as lung when the cysts are located peripherally [9].

The WHO-IWGE classification; in 1995 standardized and allowed a natural grouping of the cysts into three relevant groups of CE [Cystic echinococcosis]: active, transitional, and inactive; this classification added a "cystic lesion" (CL), to Gharbi classification [9, 10].

The transitional cysts according with WORL HEALTH classification, can be differentiated into with detached endocyst and (predominantly solid with daughter vesicles. The inactive Cysts are late stages of the disease.

The Computed tomography (CT), magnetic resonance (MR) imaging, and cholangiopancreatography (MRCP) are indicated in [1] subdiaphragmatic location, [2] disseminated disease, [3] extra abdominal locations, [4] in complicated cysts (abscess, cysto-biliary fistulae) and [9] in some cases when is necessary in the pre-surgical evaluation. MRI imaging should be preferred to CT due to better visualization of liquid areas.

#### **3. Serology of the echinococcus granuloses**

According with some authors [9] the Sensitivity of the serum antibody detection using indirect hemagglutination, ELISA, or latex agglutination, in the hydatid cyst fluid antigens, is between 85 and 98% for liver cysts, 50–60% for lung cysts and 90–100% for multiple organ cysts.

Other cestode infections such as E. multilocularis and Taenia solium, malignancies, liver cirrhosis and presence of anti-P1 antibodies limits the Specificity of all those tests due to this possibility, so a confirmatory test should be used as: (arc-5 test; Antigen B (AgB) 8/12 kDa subunits or EgAgB8/1 immunoblotting) [9].

Any organ could be affected by Echinococcal cysts, including the muscles but the commonest organs affected are lungs, liver, and spleen. If the liver is affected, might cause a compartmental abdominal Syndrome, and might cause obstructive jaundice when there is compression to the biliary system. When the lungs are affected, the patients could present with productive cough, weight loss and poor appetite (**Figures 1** and **2**).

Rupture of the cyst into pleural cavity can with shortness of breath and on chest x-ray it can be confused with pleural effusion, that could wrongly make the doctors to insert a chest drain into the cyst for mistake, founding later in another chest x-ray/or CT-chest a cystic cavity [5, 6, 8] (**Figure 3**).

The main aim of our study was to find out the prevalence of the Hydatid Cysts in children and found up the organs more common affected in children.

#### **Figure 1.**

*Hydatid cysts in the liver and left lung. Source: Author's record.*

#### **Figure 2.** *Hydatid cyst right lung lower lobe. Source: Author's record.*

#### **Figure 3.**

*Intercostal drainage into a cyst cavity of a hydatid cyst in the right lung, mistakenly for parapneumonic pleural effusion. Source. Author's record.*

### **4. Method**

We performed a retrospective study of every child of 3 to 12 years of age admitted in our surgical pediatric ward (N 56), suffering from hydatid cyst. We studied patients with this diagnosis from April 2015 to April 2021. Were studied 56 patients: analyzing the age, sex, localization of the cyst, treatment, and complications. The diagnosis was based on clinical history, physical examination, serology test, abdominal ultrasound, chest X ray, Computer Tomography (CT) and histology. The ultrasound ad CT scans were the most useful investigations in the diagnostics.

The decision to perform a surgical treatment was based on the size of the cyst when it was 6 cm or more, and when the patient having compressive symptoms and signs of complicated hydatid cyst. In hydatid cysts on the liver the compressive symptoms and sings were jaundice, itchiness, abnormal liver function testes; In Hydatid cyst on the lung; the patient could present productive cough, shortness of breath, when there is a bronchial communication, and ruptured of the cyst to the pleural cavity.

Patients with hydatid liver cyst and those with lung hydatid cysts where was showed in the CT no communication of the cyst cavity to a bronchus were performed PAIR (puncture – aspiration- injection and re aspiration, through laparotomy and thoracotomy on those with cysts in the lung. Was use 5% hypertonic saline solution for the injection considering that this concentration of the saline solution is enough to kill the Ovo's; after the PAIR, the cyst was opened and removed the germinal layer

(endocyst) and taken it for histopathology examination as a confirmation of the disease; a capitonage was done in every cyst and a drain was let in the cystic cavity. In case of lung hydatic cyst was let an intercostal drain into the cyst cavity and also into the pleural space.

In the post-operative time, we continued the children with Albendazole (20- 50 mg/kg/day) and Praziquantel (30-40 mg/kg/day) for 3 months; depending on the resolution of the cysts in some cases the Albendazol was given more than 3 months, depending on the result of the liver function tests performed monthly to rule out hepatic toxicity.

Patients with hydatid cyst size of 5 cm or less, and with no signs of compression or any other complications were treated conservatively with the combination of Albendazole and Praziquantel this treatment was given for 3 months or more depending on the resolution of the cysts.

Full Blood Count and liver function test were performed before the initiation of the treatment and every month after starting with medical treatment to find out drug toxicity.

## **5. Results**

Were analyzed 56 children, 25 of them (44.6%) had Cysts in the liver, 23 (41%) had lung Cysts. Some patients 8.9% had cysts affecting liver, lung, spleen and in other organs shown in **Table 1**.

As it can be seen in the **Table 1**, the most affected group of age was the one of patients from 5 to 10 years for 52% of the patients, the group of children with more than 10 years was the second in frequency with 36%.

The presentation of hydatid cysts in liver were more frequent in male with 28.6% than in females 16%; on the other hand; lung hydatid cysts were more frequent in female affecting 26.8%, as is showing in **Table 2**.

In 40 cases (70%) was performed a surgical treatment (PAIR and enucleation of the endocyst); in 27% of the patients with Lung Hydatid cysts to whom were performed this procedure developed in the post operatory a bronchus pleural fistula that closed by Itself mostly in the first week (**Table 3)**.

In 18% of our cases the treatment was medical treatment without surgery during a period of 6 to 8 months, expressed in **Table 4**.


#### **Table 1.**

*Patients' age vs. organs location of the cyst.*


#### **Table 2.**

*Cysts location vs. gender.*


#### **Table 3.**

*Complications vs. cyst's location.*


*The histopathology examination of the germinal layer confirmed the echinococcus granulosus.*

#### **Table 4.**

*Patient vs. treatment performed.*
