Hydatid disease, attributed to the tapeworm Echinococcus granulosus, poses a significant health threat in regions where it is endemic. Here, we present a case involving a 15-year-old boy from rural Pakistan who initially sought medical attention due to a persistent cough and hemoptysis. Despite initially testing negative for serological markers, imaging studies revealed well-defined cysts in both lungs. Confirmation of the diagnosis was achieved through histopathological examination. Management includes albendazole therapy and surgical excision of the cyst. Our case underscores the diagnostic challenges associated with seronegative cases and underscores the importance of considering hydatid disease in endemic regions, irrespective of typical serological markers. This report enhances understanding regarding the clinical presentation, diagnostic approach, and management strategies for pulmonary hydatid cysts.

Pulmonary hydatid disease remains a global public health issue. Symptoms often result from cyst rupture, causing fever, cough, and hemoptysis. Radiographs may show homogeneous masses, air-fluid levels, or the pathognomonic \"water lily\" sign. Surgical removal is the primary treatment, with early diagnosis crucial to prevent acute hypersensitivity reactions and death.

In April 2022 and December 2022, the New Hampshire Department of Health and Human Services confirmed 2 cases of locally acquired human pulmonary cystic echinococcosis caused by Echinococcus granulosus tapeworms. Both patients reported dressing locally hunted moose and exposure to dogs.

Hydatidosis is one of the most important zoonotic diseases with a worldwide distribution and it seems that the survival of Echinococcus granulosus in nature for many years, is due to having different mechanisms to escape from the host immune systems. One of these efficient mechanisms is the production of various antigens and proteins by the larva of the parasite and the main purpose of this study is evaluation of manifestation of various antigens in different parts of intermediate host. The hepatic and pulmonary hydatid cysts were gathered from sheep and the antigens of different parts of the cysts (laminated layer, protoscolices and cyst fluid) were separated and analyzed by SDS-PAGE and then transferred to nitrocellulose paper and finally, Western blot analysis was evaluated the immunogenicity of proteins. The antigens of laminated layer, protoscolices and hydatid cyst fluid, in different tissues of the liver and lungs, manifest various proteins and also these antigens are immunogenically different. Also, it is found more immunogenic proteins in the laminated layer than the other parts of the cysts. The various proteins are generated by Echinococcus granulosus larva depending on the type of tissues attacked by the parasite. Increasing the chance of survival may be the main cause of manifestation various antigens in different parts of cysts and host tissues. These antigenic variations might have made diagnostic serologic test unreliable.

Hydatid cystic disease is a significant clinical problem in endemic countries. Hydatid cysts are most commonly located in the liver and lungs. Primary mediastinal hydatid cyst is a rare clinical entity. The diagnosis must be considered in a patient with a mediastinal mass, particularly in endemic regions. Mediastinal hydatid cysts causing paralysis of phrenic and recurrent laryngeal nerves have been rarely reported. We describe a rare case of primary mediastinal hydatid cyst associated with diaphragmatic palsy caused by compression of the left phrenic nerve, which was successfully treated with partial cystectomy and capitonnage with hemidiaphragmatic plication.

BACKGROUND: Our purpose is to report our experience in the management of pulmonary hydatid cysts ruptured in the pleura. Materiel and methods: We collected all records of patients with a ruptured hydatid cyst of the lung in the pleura who underwent surgery for this in the department of thoracic surgery of the CHU Hassan II of Fes during the 6-year period that started in 2010.
RESULTS: The study included 20 men and 14 women with an average age of 30.44 ± 18.4 years. Radiological findings showed a hydropneumothorax in 21 cases, hydrothorax in 10, pachypleuritis in 29, and a floating membrane in 13 cases. In all cases, pleuropulmonary decortication was associated with pericystectomy in 20 cases and parenchymal resection in 3 cases. A hydatid membrane bathing in the pleural cavity was found in 32 cases. The postoperative course was uneventful in 28 cases.
CONCLUSIONS: Long-term follow-up should be established to detect possible recurrences or pleural dissemination, which appear to be prevented by long-term use of anthelmintic agents.

The clinical manifestations of hydatidosis are various and related to anatomic location. Defining frequent symptoms and signs of the disease is imperative for early management of it. The aim of this report was to analyse the clinical features of infected children with hydatid cysts located in different organs. In this study, medical charts of 57 children between 3 and 16 years of age with hydatid cyst admitted to Pediatric Wards of Nemazee Hospital were evaluated over a 12 year period (from 2003 to 2014, prospectively). All the epidemiologic, clinical, paraclinical and therapeutic data were collected. The frequencies of hydatidosis in males and females were 42.1 and 56.1%, respectively. Hydatid cysts were found in the liver and lungs in 59.6 and 33.3% patients respectively and 2 patients had an asymptomatic cyst in the heart with concomitant liver and lung cysts. The right upper quadrant pain (100%) was the most common symptom in the liver cysts. Phlegm (78.9%), Dyspnea (57.9%), acute (47.4%) and chronic cough (47.4%) were mostly seen in lung hydatid cysts. Some symptoms such as fever (68.4%) and weakness (59.6%) were the most common presenting symptoms in both groups. All children were treated through surgical approaches plus medical treatment. In the present report, liver was the most common site of involvement in children. Liver hydatidosis should be considered in children with upper quadrant pain and pulmonary hydatidosis in children complaining of phlegm and dyspnoea.

Pulmonary hydatid cyst with co-existing aspergillosis is rare. Till date, there are only two documented reports of this double pathology being diagnosed on cytology. The present case is of a young immunocompetent female who presented with respiratory complaints including intermittent hemoptysis. Chest X-ray and CT thorax revealed two well-defined lesions in the lower lobe of left lung that was suggestive of either infective or benign neoplastic etiology. But as hydatid cyst was not suspected either clinically or radiologically, FNA was performed. Based on the typical cytomorphological features a definitive diagnosis of hydatid cyst with aspergillosis was offered on cytology that was later confirmed on histopathology. To the best of our knowledge this is only the third report of pulmonary echinococcosis with aspergillus co-infection being diagnosed on cytology. The purpose of reporting this case is to draw attention to the rare possibility of co-existing aspergillus infection in pulmonary echinococcosis even in immunocompetent individuals, which can complicate the clinico-radiological picture. However, both pathologies can be effectively and accurately diagnosed on cytology, based on which proper treatment can be initiated. Diagn. Cytopathol. 2016;44:696-699. © 2016 Wiley Periodicals, Inc.