Peripheral blood eosinophils: an important reference for radiologists to distinguish between pulmonary paragonimiasis and tuberculous pleurisy in children.

OBJECTIVE: In this study, we examined the value of chest CT signs combined with peripheral blood eosinophil percentage in differentiating between pulmonary paragonimiasis and tuberculous pleurisy in children. METHODS: Patients with pulmonary paragonimiasis and tuberculous pleurisy were retrospectively enrolled from January 2019 to April 2023 at the Kunming Third People's Hospital and Lincang People's Hospital. There were 69 patients with pulmonary paragonimiasis (paragonimiasis group) and 89 patients with tuberculous pleurisy (tuberculosis group). Clinical symptoms, chest CT imaging findings, and laboratory test results were analyzed. Using binary logistic regression, an imaging model of CT signs and a combined model of CT signs and eosinophils were developed to calculate and compare the differential diagnostic performance of the two models. RESULTS: CT signs were used to establish the imaging model, and the receiver operating characteristic (ROC) curve was plotted. The area under the curve (AUC) was 0.856 (95% CI: 0.799-0.913), the sensitivity was 66.7%, and the specificity was 88.9%. The combined model was established using the CT signs and eosinophil percentage, and the ROC was plotted. The AUC curve was 0.950 (95% CI: 0.919-0.980), the sensitivity was 89.9%, and the specificity was 90.1%. The differential diagnostic efficiency of the combined model was higher than that of the imaging model, and the difference in AUC was statistically significant. CONCLUSION: The combined model has a higher differential diagnosis efficiency than the imaging model in the differentiation of pulmonary paragonimiasis and tuberculous pleurisy in children. The presence of a tunnel sign on chest CT, the absence of pulmonary nodules, and an elevated percentage of peripheral blood eosinophils are indicative of pulmonary paragonimiasis in children.

Risk factors and clinical features for pulmonary paragonimiasis-associated pneumothorax.

BACKGROUND: Pulmonary paragonimiasis, a food-borne zoonotic helminthiasis, is a parasitic disease of the lung caused by infection with trematodes species of the genus Paragonimus. Although pneumothorax has been reported as occuring with paragonimiasis, to date no study has been performed concerning the clinical features and predictive risk factors for this condition. METHODS: This retrospective study, which aims to fill this gap, was conducted at Jeonbuk National University Hospital. All patients (aged ≥19 years) were diagnosed with paragonimiasis between May 2011 and December 2021. Medical records were reviewed and information concerning age, sex, vital signs, underlying diseases, clinical signs and symptoms, laboratory findings, radiologic findings, treatment, and clinical outcomes was collected. An odds ratio (OR) for the risk factors associated with pneumothorax was calculated using the binary logistic regression model. RESULTS: Among 179 consecutive patients diagnosed with pulmonary paragonimiasis, the postive rate of pneumothorax was 10.6% (19/179). Pneumothorax occurred mostly in the right lung (78.9%, 15/19), and intrapulmonary parenchymal lesions showed an ipsilateral relationship with pneumothorax (94.7%, 18/19). Fifteen patients (78.9%, 15/19) of pneumothorax associated with pulmonary paragonimiasis are accompanied by pleural effusion. Most of patients with pneumothorax (89.5%, 17/19) underwent chest tube insertion as a first treatment. Three patients (15.8%) showed relapses but in no case was a death recorded. Asthma (odds ratio [OR] 8.10, 95% confidence interval [CI] 1.43-45.91), chest pain (OR 8.15, 95% CI 2.70-24.58), and intrapulmonary lesions (OR 8.94, 95% CI 1.12-71.36) were independent risk factors for pulmonary paragonimiasis-associated pneumothorax. CONCLUSIONS: Our findings suggest that clinicians should keep in mind the possibility of pneumothorax when approached by patients with pulmonary paragonimiasis complaining of chest pain, accompanied by intrapulmonary lesions or with asthma as an underlying disease.

[Case of Abdominal Colicky Pain Caused by Hepatic Paragonimiasis].

In Korea, the prevalence of paragonimiasis has decreased markedly since 1970 and is now rarely encountered. Although the lung is the primary site of paragonimiasis, ectopic infestation can occur in other sites. The central nervous system is the most commonly involved ectopic site, accounting for only approximately 1% of all paragonimiasis patients. Therefore, the liver is an extremely rare site of ectopic infestation. The authors experienced the case of a 55-year-old female with hepatic paragonimiasis who presented with abdominal colicky pain.

Exudative pleural effusion caused by lung fluke infection: A practical diagnostic approach.

OBJECTIVES: Pleural effusion caused by lung fluke is a rare etiology of exudative pleural effusion (EPE), which is often misdiagnosed or delayed. We aim to summarize the diagnosis and treatment course of EPE caused by lung fluke infection and put forward a practical diagnosis approach. METHODS: We retrospectively analyzed the diagnosis and treatment of 14 cases of EPE caused by lung fluke infection diagnosed by enzyme-linked immunosorbent assay of serum antibodies or egg detection. RESULTS: All patients (100%) with an absolute count of eosinophils in peripheral blood exceeded 0.5 × 109/l, and 10 patients (71.4%) had a history of special ingestion. Eosinophilic PE occurred in 11 patients (78.6%), pleural biopsy of medical thoracoscopic demonstrated eosinophils infiltration in nine patients (64.3%), and parasite eggs in one patient. All patients showed positive intradermal tests for Paragonimus-specific antigens and enzyme-linked immunosorbent assay of serum antibodies to Paragonimus. CONCLUSION: For patients with unexplained PE, lung fluke infection should be highly suspected when pleural fluid or pleural biopsy shows eosinophilic PE or eosinophils infiltration, especially for patients with certain diet history.

Detection of Human Paragonimiasis by ELISA Using Recombinant Paragonimus westermani Cysteine Protease 7.

Paragonimiasis is an important but neglected foodborne trematodiasis caused by Paragonimus mexicanus in Costa Rica. Immunological techniques for diagnosing this parasitosis in humans do not exist in Central America. The objective of the present study was to use recombinant Paragonimus westermani cysteine protease 7 to standardize an ELISA for the detection of antibodies against Paragonimus spp. Human sera positive for P. westermani, P. mexicanus, or Paragonimus spp., human sera infected with other helminths, as well as sera of healthy humans without parasitic infections, were analyzed. The sensitivity of the ELISA was 92.9%, and the specificity was 91.9%. This report is the first to describe the development of an ELISA for the diagnosis of Paragonimus spp. in Costa Rica and Central America. Using this ELISA in the health system of Costa Rica is recommended to detect infections.

Pulmonary Paragonimiasis: A Case Series.

Paragonimiasis contributes to significant foodborne zoonosis worldwide. The major mode of transmission in humans is by consumption of uncooked or undercooked crabs and crayfish harbouring Paragonimus metacercariae. It begins with symptoms like fever and lower respiratory involvement from a few months to a year, mimicking those of tuberculosis and leading to diagnostic delay. Here, we report two cases of paragonimiasis during a period of nine months. Both cases presented with symptoms of productive cough with rusty sputum, chest pain, along with eosinophilia, and pleural effusion and had a history of consumption of smoked crab from the local river. The diagnosis was established by microscopic demonstration of Paragonimus ova in the sputum. They were treated with praziquantel and recovered. Indeed, it is challenging to diagnose paragonimiasis due to the lack of its specific symptoms but should be considered in the differential diagnosis of eosinophilia and pleural effusion in such lung diseases. Keywords: case reports; eosinophilia; paragonimiasis; pleural effusion.

A case of a dog with paragonimiasis after consumption of raw deer meat.

A 6-year-old castrated male Cavalier King Charles Spaniel was referred to the Animal Medical Center, Tokyo University of Agriculture and Technology, for examination and treatment of recurrent pneumothorax. Chest radiography and computed tomography showed multiple cavitary lesions in the caudal right posterior lobe. These lesions were surgically excised via thoracotomy. Subsequent histopathological examination revealed paragonimiasis. In the postoperative review, we found that the owner had fed raw deer meat to the dog four months earlier. Deer meat has attracted attention as a source of Paragonimus in humans. To our knowledge, this is the first report of Paragonimus infection in a dog due to deer meat consumption.

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.

Case Report: Reemerging Paragonimiasis in Umphang District, Thailand.

Paragonimiasis is a food-born zoonotic parasitosis caused by Paragonimus spp. Six cases of reemerging paragonimiasis within the Karan hill-tribe near the Thai-Myanmar border were evaluated to review clinical manifestations, predisposing factors, and treatment regimens. All patients tested positive for paragonimiasis eggs and presented with an array of symptoms, including chronic cough, hemoptysis, peripheral eosinophilia, and thoracic radiograph abnormalities. All fully recovered after a 2- to 5-day course of 75 to 80 mg/kg/day praziquantel. We conclude that paragonimiasis should be considered during differential diagnoses to promote early treatment and to prevent misdiagnosis of reemerging or sporadic cases. This applies particularly to endemic regions and high-risk groups known to habitually consume raw or undercooked intermediate or paratenic hosts.

A Cluster of Paragonimiasis with Delayed Diagnosis Due to Difficulty Distinguishing Symptoms from Post-COVID-19 Respiratory Symptoms: A Report of Five Cases.

Paragonimiasis caused by trematodes belonging to the genus Paragonimus is often accompanied by chronic respiratory symptoms such as cough, the accumulation of sputum, hemoptysis, and chest pain. Prolonged symptoms, including respiratory symptoms, after coronavirus disease 2019 infection (COVID-19) are collectively called post-COVID-19 conditions. Paragonimiasis and COVID-19 may cause similar respiratory symptoms. We encountered five cases of paragonimiasis in patients in Japan for whom diagnoses were delayed due to the initial characterization of the respiratory symptoms as a post-COVID-19 condition. The patients had consumed homemade drunken freshwater crabs together. One to three weeks after consuming the crabs, four of the five patients were diagnosed with probable COVID-19. The major symptoms reported included cough, dyspnea, and chest pain. The major imaging findings were pleural effusion, pneumothorax, and nodular lesions of the lung. All the patients were diagnosed with paragonimiasis based on a serum antibody test and peripheral blood eosinophilia (560-15,610 cells/µL) and were treated successfully with 75 mg/kg/day praziquantel for 3 days. Before diagnosing a post-COVID-19 condition, it is necessary to consider whether other diseases, including paragonimiasis, may explain the symptoms. Further, chest radiographic or blood tests should be performed in patients with persistent respiratory symptoms after being infected with COVID-19 to avoid overlooking the possibility of infection.

Cerebral Paragonimiasis Presenting with Dementia.

We report a case of an 80-year-old Korean man with chronic cerebral paragonimiasis who presented with progressive memory impairment. He suffered from pulmonary paragonimiasis 60 years ago and has been experiencing epilepsy since the age of 45. He began experiencing memory and cognitive deterioration 3 years ago. He visited the neuropsychiatric department of our hospital to check his symptoms and health from a year ago. Contrast-enhanced brain magnetic resonance imaging study revealed calcifications and cystic lesions encompassing the right temporo-occipital region. Encephalomalatic changes were also observed in the right occipital and temporal areas. The anti-Paragonimus specific IgG antibodies in his serum showed a strong positive response. The neuropsychological test results showed a Global Deterioration Scale of 4 and a Clinical Dementia Rating Scale of 1. The chronic cerebral paragonimiasis lesions in the patient's right temporo-occipital region might induce the dementic change.

Pulmonary Paragonimiasis in Native Community, Esmeraldas Province, Ecuador, 2022.

Paragonimiasis is a food-borne infection caused by several species of the Paragonimus fluke. Clinical manifestations can mimic tuberculosis and contribute to diagnostic delay. We report a cluster of paragonimiasis in a community in Ecuador, where active surveillance was set up after detection of the first 2 cases.

A clinical review of human disease due to Paragonimus kellicotti in North America.

Human autochthonous infections with the trematode Paragonimus kellicotti are increasingly being reported in North America, but the true prevalence and geographic distribution are unknown. Ingestion of raw crayfish is reported in most human cases, typically in the context of alcohol intoxication. Risk of infection varies depending on what part of the crayfish is ingested as metacercariae of P. kellicotti (>50% mature to adults) localize to the heart and pericardium of the crayfish. Reported human cases have manifested primarily in otherwise healthy young adults presenting with severe eosinophilic pneumonia, pleuritis, systemic symptoms, dermatologic lesions and cerebral involvement. However, it is likely that many infections go unreported due to lack of awareness, mild illness or the absence of rapid commercially available diagnostic tests. Promising advances have been made related to novel diagnostic targets. Conservation of these antigen targets among at least four Paragonimus species could make these antigens viable for diagnostic testing of P. kellicotti specifically as well as other Paragonimus species, but additional studies and funding investments are required. Public and physician awareness may have improved due to targeted education campaigns, but ongoing activities to raise awareness are needed, particularly in areas where cases have not been frequently reported to date.

A case of cerebral paragonimiasis misdiagnosed as eosinophilic granulomatosis with polyangiitis.

Paragonimiasis is a parasitic disease caused by Paragonimus westermani infection, and migration to the brain results in cerebral paragonimiasis. Cerebral paragonimiasis is now extremely rare, but a few cases are still reported. A 48-year-old Japanese woman presented with right-hand convulsion, right-hand numbness, sputum, and fatigue. Chest computed tomography demonstrated multiple nodular lesions, and head computed tomography revealed a hemorrhagic lesion in the left motor cortex. Magnetic resonance imaging revealed multiple small ring-shaped lesions with surrounding edema. Laboratory evaluation demonstrated peripheral eosinophilia. We considered eosinophilic granulomatosis with polyangiitis and started steroid treatment as a diagnostic therapy since we wanted to avoid cerebral lesion biopsy if possible. However, the patient underwent craniotomy surgery after steroid treatment for four months because a new intracerebral mass lesion had appeared. Trematode eggs were detected in the sample, and the final diagnosis was cerebral paragonimiasis. The patient was successfully treated with praziquantel. Cerebral paragonimiasis is extremely rare but should be considered in the differential diagnosis if atypical intracranial hemorrhage and peripheral eosinophilia are observed.