Diagnosis and surgical management of pericardial effusion due to paragonimiasis

Paragonimiasis

Paragonimiasis is a zoonotic disease caused by lung flukes of the genus Paragonimus. Humans usually become infected by eating freshwater crabs or crayfish containing encysted metacercariae of these worms. However, an alternative route of infection exists: ingestion of raw meat from a mammalian paratenic host. Adult worms normally occur in pairs in cysts in the lungs from which they void their eggs via air passages. The pulmonary form is typical in cases of human infection due to P. westermani, P. heterotremus, and a few other species. Worms may occupy other sites in the body, notably the brain, but lung flukes have made their presence felt in almost every organ. Ectopic paragonimiasis is particularly common when infection is due to members of the P. skrjabini complex. Human paragonimiasis occurs primarily in the tropics and subtropics of Asia, Africa, and the Americas, with different species being responsible in different areas (Table 6.1).

Massive secretions in paragonimiasis pleural effusion: a new finding concerning clinical recognition and treatment

Some paragonimiasis patients in Chongqing, southwest China, have recently exhibited pleural effusions (PEs) with massive viscous secretions. This study aimed to investigate their clinical characteristics, thereby promoting effective treatments. A 3-year retrospective review of paragonimiasis patients who were admitted for nonhomogeneous PEs at Chongqing University Three Gorges Hospital was conducted. Epidemiological data, symptoms, laboratory and imaging findings, treatments, and outcomes were analyzed. Twenty-eight patients were identified, of which 22 (78.6%) were males and 22 (78.6%) were rural residents. Respiratory (85.7%) and constitutional (57.1%) symptoms were common. Paragonimus-specific ELISA was positive in all patients. Eosinophilia was detected in all patients in peripheral blood and PEs. Irregular hyperdense signals were observed in PEs by chest CT scans (96.4%) and ultrasonography (100.0%). Thoracic closed drainage failed in 10 patients (conservative group) because of tube blockage and was eventually replaced by video-assisted thoracoscopic surgery (VATS). Eighteen patients (surgery group) initially underwent VATS, or thoracotomy surgery, without complications. Massive secretions, described as "bean-dregs" or "egg-floccule," were detected intraoperatively, which explained the imaging findings and tube blockage. All patients recovered well after 2-3 courses of postoperative praziquantel treatment. Viscous secretions in paragonimiasis patients warrant great concern. Irregular hyperdense signals in effusions are important characteristics in CT scans and ultrasonography. Treatments such as thoracic closed drainage may fail due to viscous secretions blocking the tube; therefore, surgeries should be considered. In-depth multidisciplinary research may help determine the optimal treatment strategy and reveal the origin of these secretions.

Lung flukes of the genus Paragonimus: ancient and re-emerging pathogens

The title of this article refers to Table 1 in Zhou (2022, Infectious diseases of poverty: progress achieved during the decade gone and perspectives for the future. Infectious Diseases of Poverty 11, 1), in which it is indicated that Paragonimus species, like many other foodborne trematodes, are ancient pathogens that are also re-emerging to cause disease in modern times. This article provides a general overview of Paragonimus species and the disease they cause. This is followed by comments on several specific topics of current interest: taxonomy and distribution of members of the genus; details of the life cycle; global and regional prevalence of paragonimiasis; genomics of lung flukes and possible effects of global environmental change. Unresolved questions relating to these topics are discussed and gaps in knowledge identified.

Paragonimus infection: Rare manifestation with pericardial effusion: A Case report and Literature review

Background

Paragonimus, is a globally distributed trematode, with human disease limited to endemic regions. It can be transmitted to humans through ingestion of intermediate hosts that are crustaceans. Most symptomatic infections consist of pulmonary disease, and in aberrant migration of immature flukes, extrapulmonary manifestations may occur. These presentations are relatively uncommon and may affect various organs with atypical Clinico-radiological pathologies that are often challenging to diagnose. Pericardial involvement has scarcely been reported before. Furthermore, the management, clinical outcomes and potential complications of this involvement remain unclear.

Case report

Our patient is a 31-year-old Nepalese male who presented with abdominal distension and lower limb oedema. Initial work up revealed pericardial effusion, and analysis was suggestive of exudative lymphocytic effusion. Supported by positive QuantiFERON result along with his demographic data, the patient was treated presumptively as a case of tuberculous pericarditis, despite the negative initial Mycobacterial Tuberculosis work up. During follow up, the patient lacked clinical response and repeated echocardiography showed signs of tamponade with concomitant pleural effusion. subsequently video-assisted-thoracoscopy pericardial window along with pericardial and pleural biopsy were performed. Histopathological examination of the biopsied tissue revealed non-necrotizing granulomas containing a parasitic egg suggestive of Paragonimus. Fortunately, the patient received treatment with praziquantel and subsequently made good clinical recovery.

Conclusion

Diagnosis of extrapulmonary Paragonimus infection can be challenging given its rarity and clinical picture mimicking other infectious aetiologies. Pericardial involvement is seldom reported in the literature and clinical suspicion should be raised particularly when dealing with atypical presentations and relevant demographic data.