Ruptured hydatid cyst presenting with a hydropneumothorax in a 16-year-old boy: A case report from Syria

Abstract

Introduction and importance

The rupture of the pulmonary hydatid cyst is a serious clinical problem because it causes significant local and systemic symptoms. Also, cyst rupture is not rare, but it is one of the most frightening and severe complications of hydatid cysts in the lung.

Case presentation

We report a 16-year-old male with a 15-x-15-cm cyst in the lower lobe of his left lung that had ruptured into the pleural space and bronchus, resulting in a fistula. The germinal layer was discovered within the fluid of the effusion inside the pleural cavity. The cyst was surgically excised and treated with albendazole. A three-month follow-up found the patient to be healthy and free of symptoms.

Clinical discussion

The presented case highlights the importance of early detection and management of pulmonary hydatid cysts. The rupture of these cysts can lead to significant local and systemic symptoms, as well as the formation of fistulas.

Echinococcus infection of the lung is relatively common, but hydatid cysts in general require special management due to their tendency to go undiagnosed until they are large and accompanied by cysts in other areas.

The presented case highlights the importance of early detection and proper management of pulmonary hydatid cysts to prevent complications and ensure successful outcomes for patients.

Conclusion

Infection of the left lung with Echinococcus is generally common, but hydatid cysts, in general, need special management because they usually are not detected early, are large, incidentally discovered, and are accompanied by cysts in other areas.

Highlights

• •The rupture of a giant pulmonary hydatid cyst is one of the most scary medical issues.
• •The cyst was enormous, measuring about 15 by 15 cm, and it burst in the pleural cavity.
• •More data on these issues should be given to alert practitioners and reduce mortality.

1. Introduction

Echinococcus granuloses is the culprit of Hydatid cysts on humans' lungs [1], which is especially common in rural areas [2]. This parasite is transmitted to humans by direct contact with dogs or by eating vegetables and foods contaminated with their feces containing Echinococcus eggs [3]. Cysts usually occur in several locations of the body, the most important of which are the liver and lungs and may occur in other sites such as the kidneys and bone marrow [4], but the lungs are the most common place to occur in children because they have the property of flexibility that allows them to expand in size and the rupture of the cyst in them may lead to serious consequences [3]. Most of the time, the hydatid cyst on the lung does not cause any symptoms in the person with it, but on the other hand, the symptoms may appear in some patients, including coughing, nausea, vomiting, and dyspnoea [5]. Rupture of the cyst inside the pleural cavity or bronchus is one of the most important complications, which occurs due to several factors such as the expansion of the size of the cyst or cough [6]. Symptoms following the rupture can include fever and haemoptysis [4]. As for the complications of rupture, the most prominent are: bronchopleural fistula, simple pneumothorax, and empyema, so the doctor should be careful when diagnosing a hydatid cyst [7]. One of the rare medical cases we encountered involved a 16-year-old boy who was diagnosed with a hydatid cyst on the lung. The cyst had ruptured and created a fistula between the bronchus and pleural cavity causing a Pneumothorax with effusion or a Hydropneumothorax. The germinal layer or endocyst was completely located in the pleural cavity floating in the effusion which gave an unusual and interesting image on CT.

Furthermore, the study complied with SCARE 2020 Checklist [8].

2. Presentation of case

A 16-year-old Syrian male patient from a rural area was referred to the Hospital in Oct 2021 and was admitted to the emergency room with a complaint of acute coughing with yellow watery sputum, accompanied by dyspnea, hyperthermia, and severe dehydration. The patient was not able to breathe effectively and comfortably due to severe dyspnea in the supine position.

2.1. On general examination

It was noted that the pulse was 130 beats per minute, the pressure was 90/50 mmHg, the temperature was 39.5 °C, and the oxygen saturation was 98 % in ambient air. There was no history of medical or surgical issues. Pulmonary examination found diminished breath sounds over the apex of the left lung with the absence of basal sounds compared to the right side. The abdomen was found soft and the limbs free-moving.

2.2. The chest radiograph

The chest radiograph showed a large air/fluid level on the left side as shown in Fig. 1 which is consistent with a Hydropneumothorax. A CT Scan of the chest revealed the presence of a left pneumothorax with pleural effusion because of the rupture of a large hydatid cyst in the lower lobe of the left lung into a bronchus and the pleural cavity with formation of bronchopleural fistula. Also, a faint wrinkled opacity within the effusion fluid which later turned out to be the germinal layer or endocyst was seen in Fig. 2. The CT scan revealed a normal liver, and the infection was unrelated to the presence of hydatid cysts in the liver. Haematological tests showed an increase in CRP of (56.7 mg/l), white blood cells (24,600/mm³), and a severe increase in urea with a value of (75.3 mg/dl), which is consistent with severe dehydration. The hydatid serology was positive and a slight increase in hypereosinophilia was seen. At the same time, the rest of the laboratory values were within the normal range.

Fig. 1.

A chest X-ray showing a large air fluid level on the left side consistent with a Hydropneumothorax, with the outline of a cyst visible near the hilum.

Fig. 2.

On the left: A chest CT in lung window showing a large Hydropneumothorax and the cyst with an air-fluid level indicating it had ruptured into the bronchus. Notice the nearly complete absence of lung markings on the left side.

On the right: The same chest CT in soft tissue window showing a strange opacity in the effusion fluid, with a peculiar wrinkled appearance and which turned out later to be the germinal layer of the cyst.

2.3. The surgical procedure

The patient was prepared for a surgical operation to remove the hydatid cyst in the lateral position with general anaesthesia. The patient underwent a left side posterolateral thoracotomy with a posterior side incision through the sixth intercostal, where a large amount of turbid pleural fluids was found, about “1 l” and samples were sent from it for bacterial culture. The germinal layer of the hydatid cyst was also found within the fluid of the effusion and it was pulled out from pleural cavity as seen in Fig. 3. The initial cyst was located in left lower lobe and was about 15 × 15 cm big and had formed a large fistula on the bronchi. The lung was firmly attached to the chest wall and the diaphragm, and the adhesions extended to the level of the pulmonary fissure and the upper lobe. The adhesions were severed and unleashed, the lower lobes were released from the diaphragm and the chest wall, and the upper lobes and lingula were freed from the pericardium. Then, closure of the bronchial fistula and of the cystic cavity was performed with a 2-0 Vickerel suture at several levels. Complete lung decortication was performed with ventilation manoeuvres. Pleural lavage with 0.9 % saline was performed intraoperatively to clean the plura of any debris. After confirming hemostasis, lack of air leakage, and good lobular diffusion, a posterior 36F drainage tube was placed, and the wound was closed in layers.

Fig. 3.

The germinal layer or endocyst after being pulled out of the pleural cavity.

2.4. Postoperatively

The patient was monitored in the intensive care unit for 24 h. On the second postoperative day, the general condition was stable, with no hyperthermia, and the vital signs were stable and the drainage was working fine. After six days, the inflammatory signs receded, and he was placed on special treatment for hydatidosis (Albendazol 400 mg twice daily for six months) and was discharged home. The patient was followed up after two months with a Chest X-ray, and there was a significant improvement in the patient's condition, as shown in Fig. 4.

Fig. 4.

A perfectly normal chest X-ray on a two months follow-up, confirming that there is no recurrence.

3. Discussion

Echinococcus is one of 17 disregarded tropical diseases determined by the World Health Organization, affecting more than 1 million people worldwide yearly. It causes hydatid cyst, which is endemic in animal husbandry communities. Hydatid cysts can infect various organs, mostly the lung and liver, but it has also been reported in other organs. They are usually asymptomatic, relying on the size and location [9]^, [10]. Hydatid cysts usually grow slowly and are diagnosed in only 10 % to 20 % of patients less than 16 years. In a study in Iran, most of the seven adult patients with childhood infection were asymptomatic for a long period and were afterwards diagnosed randomly on chest radiographs [11]^, [12].

Most hydatid cyst patients are in close contact with animals in rural areas. Diagnosis of a hydatid cyst is usually made through a history, physical examination, imaging, and serological tests. Ultrasound and computed tomography can help diagnose hydatid cysts in the liver and lung [13]. Size did not appear to affect the short-term perioperative results, and the cysts could typically be surgically treated without lung resection [14]. Mebendazole and albendazole are usually given before and after surgery to reduce the risk of local recurrence [15]. In our case, the giant size of the cyst in the left lung of about 15 ∗ 15 cm and its rupture caused both severe local and systemic symptoms.

A hydropneumothorax is an unusual radiologic finding that occurs when both free fluid and air are present in the pleural cavity at the same time [16]. In our case, a fistula between the bronchus and pleural cavity was caused by the cyst's rupture, which led to a hydropneumothorax.

Hydatid cysts are structurally made up of three layers. Pericyst, the outermost layer, is created by compressed host tissue and a fibrous reaction. Ectocyst, the middle laminated membrane layer, is an acellular structure. Finally, the endocyst, the innermost germinative layer, creates daughter vesicles that contain protozoa [17]^, [18]. In our case, the endocyst or germinal layer has detached from the rest of the cyst and was entirely positioned in the pleural cavity and was floating in the effusion, creating an uncommon and intriguing appearance on CT.

Rupture usually occurs either during surgery or trauma, but other reasons lead to the rupture of the cyst, such as young age, large size, increased pressure and the site of injury [19]^, [20]. Furthermore, the rate of complications and mortality after surgery from the ruptured cyst is higher than from a complete cyst [21]^, [22].

Many patients return to the hospital with progressive stages of the disease due to the deficient conditions and the remnants of the crisis that Syria has suffered for many years, which caused trouble in medical care. A hydatid cyst can also cause severe complications if it is not managed well from the beginning. These complications may lead to an enlargement of the cyst and its rupture, as in our case, and a fatal anaphylactic shock. Moreover, the proliferation of several “daughter” cysts can lead to secondary infection and fistula formation, as in our case [23].

4. Conclusion

The hydatid cyst is a serious disease if it ruptures, especially in developing countries, because of the difficulty of providing immediate health care. Infection of the left lung and hydropneumothorax are generally uncommon. But hydatid cysts, in general, need special management because they are not detected early, are large, suddenly discovered, and are accompanied by cysts in other areas.

Abbreviations

N/A.

Availability of data and materials

All data generated or analysed during this study are included in this published article.

Consent for publication

Written informed consent was obtained from the patient's parents/legal guardian for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.

Ethical approval

Ethical approval was also taken from the Faculty of Medicine at Al-kalamoon University.

Funding

The authors declare that they have no funding sources.

Author contribution

JA, HH, Ammar I, have participated in writing the manuscript, and reviewing the literature. Ammar I critically and linguistically revised the manuscript. JA contributed to the revision and preparation of the manuscript. Adnan I conceived and supervised the conduct of the study. All authors read and approved the final manuscript.

Guarantor

Jamal Ataya, Faculty of Medicine, University of Aleppo, Syria.

Registration of research studies

Not applicable.

Declaration of competing interest

The authors declare that they have no competing interests.