Pancreatic Paragonimiasis in Children: A Case Report

ABSTRACT

A few pediatric cases of abdominal paragonimiasis have been described. Here we describe a case of pulmonary and abdominal paragonimiasis with involvement of the pancreas in a 9-year-old boy. The aim of this study was to analyze the clinical and radiological features of pancreatic paragonimiasis in children and raise the awareness of this disease.

Subtly Increased Focal FDG Activity in the Liver Due to Paragonimiasis

ABSTRACT

A 32-year-old man underwent 18 F-FDG PET/CT to evaluate suspicious hepatic metastases, which were revealed by ultrasonography and MRI. The FDG PET/CT images demonstrated only one focus of subtly increased activity in the liver without abnormality elsewhere. The pathological result from hepatic biopsy was consistent with Paragonimus westermani infection.

Pulmonary Paragonimiasis: The Detection of a Worm Migration Track as a Diagnostic Clue for Uncertain Eosinophilic Pleural Effusion

A 38-year-old woman with sustained right chest pain was referred to our hospital. She showed pleural effusion and peripheral blood eosinophilia. Thoracentesis revealed eosinophilic pleural effusion in which the smear, culture and cytological examinations were all negative. Although she had no notable dietary history, chest CT revealed linear opacities, which suggested the migration tracks of paragonimiasis. The diagnosis was confirmed using enzyme-linked immunosorbent assays, which showed elevated Paragonimus westermani and Paragonimus miyazakii antibody levels. After the initiation of praziquantel therapy, all clinical findings were promptly improved. The detection of a migration track may therefore be useful in the diagnosis of paragonimiasis.

Pleural fluid characteristics of pleuropulmonary paragonimiasis masquerading as pleural tuberculosis

BACKGROUND/AIMS

Pleuropulmonary paragonimiasis produces no specific symptoms or radiologic findings, allowing for the possibility of misdiagnosis. We evaluated the specific clinical and pleural fluid features of pleuropulmonary paragonimiasis masquerading as pleural tuberculosis.

METHODS

We retrospectively analyzed the clinical and radiologic characteristics of 20 patients diagnosed with pleuropulmonary paragonimiasis between 2001 and 2011.

RESULTS

In total, 17 patients presented with respiratory symptoms, including dyspnea (30%), hemoptysis (20%), cough (20%), and pleuritic chest pain (15%). Chest radiographs revealed intrapulmonary parenchymal lesions, including air-space consolidation (30%), nodular opacities (20%), cystic lesions (15%), ground-glass opacities (10%), and pneumothorax (5%). A pleural fluid examination revealed eosinophilia, low glucose levels, and high lactate dehydrogenase (LDH) levels in 87%, 76%, and 88% of the patients, respectively. These traits helped to distinguish pleuropulmonary paragonimiasis from other pleural diseases such as parapneumonic effusion, malignancy, and pleural tuberculosis.

CONCLUSIONS

Pleuropulmonary paragonimiasis is often initially misdiagnosed as other pleural diseases. Therefore, it is important to establish the correct diagnosis. In patients with unexplained pleural effusion living in paragonimiasis-endemic areas, pleural fluid obtained by thoracentesis should be examined to distinguish pleuropulmonary paragonimiasis. When marked eosinophilia, high LDH levels, and low glucose levels are identified in pleural fluid, physicians could consider a diagnosis of pleuropulmonary paragonimiasis.

Contrast-enhanced ultrasonographic findings of hepatic paragonimiasis

AIM: To investigate the features of hepatic paragonimiasis on contrast-enhanced ultrasound (CEUS) imaging.

METHODS: Fifteen patients with hepatic paragonimiasis who were admitted to our hospital between March 2008 and August 2012 were enrolled to this study. The conventional ultrasound and CEUS examinations were performed with a Philips IU22 scanner with a 1-5-MHz convex transducer. After conventional ultrasound scanning was completed, the CEUS study was performed. Pulse inversion harmonic imaging was used for CEUS. A bolus injection of 2.4 mL of a sulfur hexafluoride-filled microbubble contrast agent (SonoVue) was administered. CEUS features were retrospectively reviewed and correlated with pathological findings.

RESULTS: In total, 16 lesions were detected on CEUS. The mean size of the lesions was 4.4 ± 1.6 cm (range, 1.7-6.6 cm). Subcapsular location was found in 12 lesions (75%). All the lesions were hypoechoic. Six lesions (37.5%) were of mixed content, seven (43.8%) were solid with small cystic areas, and the other three (18.8%) were completely solid. Ten lesions (62.5%) were rim enhanced with irregular tract-like nonenhanced internal areas. Transient wedge-shaped hyperenhancement of the surrounding liver parenchyma was seen in seven lesions (43.8%). Areas with hyper- or iso-enhancement in the arterial phase showed contrast wash-out and appeared hypoenhanced in the late phase. The main pathological findings included: (1) coagulative or liquefactive necrosis within the lesion, infiltration of a large number of eosinophils with the formation of chronic eosinophilic abscesses and sporadic distribution of Charcot-Leyden crystals; and (2) hyperplasia of granulomatous and fibrous tissue around the lesion.

CONCLUSION: Subcapsular location, hypoechogenicity, rim enhancement and tract-like nonenhanced areas could be seen as the main CEUS features of hepatic paragonimiasis.

[A case of Paragonimus westermani with elevated FDG uptake into a pulmonary nodular lesion and right hilar and mediastinal lymph nodes on FDG-positron-emission tomography]

A 47-year-old Chinese woman living in Japan was referred with a 2-month history of cough with hemoptysis. 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) showed increased FDG uptake into a pulmonary nodular lesion 25 mm in greatest dimension in the right upper lobe, and right hilar and mediastinal lymph nodes. Laboratory investigation did not reveal either eosinophilia or a marked elevation of serum IgE titer. A culture of bronchial lavage fluid was sterile and culture for mycobacteria was negative. Cytological examination results of transbronchial brushing samples were Class III. A partial resection of the right upper lobe was performed because of the possibility of primary lung cancer. Pathological examination of the nodular lesion showed helminthic eggs surrounded by dense inflammatory infiltrates, which mainly consisted of lymphocytes and eosinophils. Based on the findings of a serological study for helminth, the morphological characteristics of the eggs and the patient's history of eating raw crab, the patient was given a diagnosis of Paragonimus westermani, which can mimic primary lung cancer.

[Pulmonary paragonimiasis]

Paragonimiasis is a food-borne zoonosis caused by a trematode of the genus Paragonimus(1,2). Infestation is rare in Spain, but the influx of people from endemic areas should make us keep this condition in the differential diagnosis of our patients(2,5). We report the case a patient from Ecuador and resident in Spain for 7 years with active pulmonary tuberculosis on arrival in Spain and later diagnosed with of pulmonary paragonimiasis due to persistent haemoptysis. The diagnosis was established by surgical lung specimen showing granulomas containing parasite eggs and the macroscopic view of the fluke within a lung cavity. Initial tuberculosis treatment and current treatment with praziquantel controlled both conditions.

Different chest radiographic findings of pulmonary paragonimiasis in two endemic countries

We compared the chest radiographic findings of patients with pulmonary paragonimiasis in the Lao People's Democratic Republic (PDR) with a report from Korea. The clinical and radiological characteristics of 50 confirmed Laotian pleuropulmonary paragonimiasis patients were studied between March 2003 and June 2007. In 49 patients, the chest radiographs showed abnormal findings (98%). Pulmonary parenchymal abnormalities were found in all 49 patients, whereas pleural effusion was only found in 11 patients (22%). The three most common intraparenchymal findings were multiple small cysts (90%), irregular linear densities (68%), and nodular opacities (40%). The numbers of patients who had these three findings were significantly different from the Korean report (P < 0.001). In conclusion, radiographic findings of pulmonary paragonimiasis may vary among countries.

[The manifestations and clinical significance of chest CT in paragonimiasis at different clinical phases]

OBJECTIVE

To investigate the chest CT manifestations of paragonimiasis at different clinical phases.

METHODS

Forty-eight cases of paragonimiasis confirmed by laboratory studies were retrospectively analyzed. There were 30 males and e18 females ageing 9 - 66 years (average, 31.4 years). Conventional chest CT was performed in all cases and contrast enhanced CT in some cases.

RESULTS

The chest CT findings of paragonimiasis included: (1) peribronchial inflammation (n = 9); (2) infiltration (n = 13), manifested as unilateral or bilateral patchy infiltrates with hazy borders. The location and shape were variable. The typical "canal gas-path" sign was seen in a few patients; (3) nodular and masses (n = 11); (4) cysts and cavity (n = 6); (5) pleural effusion (n = 9). The CT appearances of paragonimiasis were different at different clinical phases. Peribronchial inflammation, infiltration and pleural effusion were early presentations, not distinguishable from other common infections. The appearance of nodules, masses, cysts and cavities was more common in the clinical course. At the stabilization phase, nodular cavity or pleura thickening and calcification were revealed.

CONCLUSION

There are various abnormalities on chest CT at different phases of paragonimiasis. Combination of clinical manifestations with chest CT characteristics is important in the diagnosis of paragonimiasis.

[Pulmonary paragonimiasis. Case report]

Paragonimiasis is a zoonosis affecting wild and domestic animals and human beings, caused by species of trematodes of the genus Paragonimus. Humans become infected after ingestion of raw or poorly cooked fresh water crustaceans. The aim of the present work is the description of a case of a 3-years old child, coming from Guárico State in Venezuela with a year of residence in the seashore of the Provincia Manabí in Ecuador, where he ate crabs in "ceviche". During hospitalization, he presented respiratory distress, hepatomegaly and nodules in the back. The thorax cat scan showed heavy infiltrate in both pulmonary bases and pleural compromise. Based on clinic, radiological images, an eosinophilia of 47% (Eosinophils absolute count (EAC) 6.682/mm3) and the antecedent of raw crabs ingestion, pulmonary paragonimiasis was diagnosed. Paragonimus eggs were not found in sputum and feces. ELISA with crude Paragonimus antigen was positive and Western blot revealed recognition of specific molecules. After treatment for three days with Praziquantel at a daily dose of 25 mg/kg body weight divided into three intakes, the sintomatology disappeared and radiological images and number of eosinophils diminished considerably.

Pleuropulmonary paragonimiasis due to Paragonimus heterotremus: molecular diagnosis, prevalence of infection and clinicoradiological features in an endemic area of northeastern India

In the northeastern region of India, paragonimiasis is emerging as an important public health problem. However, until now the identity of the species causing human infection has been uncertain and there has been little information on the prevalence and clinicoradiological features of infection in the community. Parasitological and immunological surveys revealed that paragonimiasis was hyperendemic in parts of Arunachal Pradesh. Egg positivity in the sputum was 20.9% and 4.1% in children (age </=15 years) and adults (age >15 years), respectively. Antibody positivity against excretory-secretory antigen of the adult worm in children and adults was 51.7% and 18.7%, respectively. Chronic cough (97.2%) and haemoptysis (83.3%) were common respiratory symptoms among egg-positive cases. Chest radiography (n=68) images from egg-positive cases showed that air space consolidation (75%), cavitary lesions (14.7%) and mediastinal adenopathy (11.8%) were very frequent. Less frequent findings were nodular lesions, bronchiectasis, mediastinal adenopathy, pleural thickening and pleural effusion. DNA extracted from eggs from the sputum of patients from Arunachal Pradesh was sequenced. Analyses of the second internal transcribed spacer (ITS2) of nuclear rDNA revealed that the species responsible is Paragonimus heterotremus.

[A case of Westermani Paragonimiasis with atypical change of CT findings]

A 47-year-old man presented with bloody sputum and a cavitary mass shadow was formed in his right middle lobe. Transbronchial lung biopsy revealed the presence of parasite eggs and eosinophil infiltration. Based on the positive reaction against Westermani Paragonimus by multiple dot ELISA, Westermani Paragonimiasis was diagnosed. The cavitary mass shadow disappeared after the treatment with Pragiquantel. This is a rare case of Westermani Paragonimiasis showing interesting changes of chest CT findings during its clinical course.

Clinical features of recently diagnosed pulmonary paragonimiasis in Korea

STUDY OBJECTIVE

Paragonimiasis is a typical food-borne parasitic disease that is common in Southeast Asia, the Far East, Latin American, and Africa. Recently, however, this disease has been seen in many parts of the world, largely due to increases in the numbers of immigrants and overseas travelers. The purpose of this study was to evaluate the clinical and radiologic features of recently diagnosed pulmonary paragonimiasis.

PATIENTS

We retrospectively analyzed the clinical and radiologic characteristics of 36 patients (21 men and 15 women; median age 48 years; range, 19 to 75) with pulmonary paragonimiasis whose conditions were diagnosed between October 1994 and September 2004.

RESULTS

Thirty-four patients (94%) presented with respiratory symptoms, including hemoptysis (n = 20, 56%) and cough (n = 17, 47%). However, chest pain (n = 5, 14%) and fever (n = 5, 14%) were less frequently reported. Chest radiography revealed intrapulmonary parenchymal lesions (n = 26, 72%), such as nodules (n = 14, 39%), linear opacity (n = 6, 17%), and airspace consolidations (n = 4, 11%), which occurred more commonly than did pleural lesions (n = 10, 28%). Most cases were initially suspected to be lung cancer or tuberculosis. In 13 patients with intrapulmonary parenchymal lesions who underwent bronchoscopy, bronchial luminal narrowing, coupled with congested or edematous mucosal changes, was seen in 7 patients (54%). Bronchial mucosal biopsy specimens exhibited chronic inflammation with eosinophilic infiltrations in three of these seven patients (43%).

CONCLUSIONS

Our findings indicate that patients with pulmonary paragonimiasis presented with a variety of clinical and radiologic findings that were different from the classic presentations reported earlier, frequently mimicking those of lung cancer or tuberculosis.

Pleuropulmonary Paragonimiasis: CT Findings in 31 Patients

OBJECTIVE

The purpose of our study was to identify any specific CT features that may help in the diagnosis of pleuropulmonary paragonimiasis.

CONCLUSION

Pleuropulmonary paragonimiasis usually manifests as a subpleural or subfissural nodule of about 2 cm in diameter that frequently contains a necrotic low-attenuation area. The constellation of focal pleural thickening and subpleural linear opacities leading to a necrotic peripheral pulmonary nodule is another frequent CT finding of paragonimiasis. Although minimal and easily overlooked, focal fibrotic pleural thickening adjacent to a pulmonary nodule can be an important clue in the diagnosis of pleuropulmonary paragonimiasis on CT.

High-Resolution Computed Tomography Findings of P. westermani

Paragonimiasis westermani, or Oriental lung fluke, is a common parasitic zoonosis, which is acquired from eating the flesh of wild boar or freshwater crabs. After being ingested by humans, the larvae of P. westermani migrate across small intestinal mucosa into the intra-abdominal space, and then finally into to the pleural space and lung parenchyma. High-resolution CT findings of P. westermani consist of worm cysts, migration track, peripheral density, bronchial wall thickening, and centrilobular nodules, which prompt serological tests and detection of eggs in sputum or BAL fluid for definitive diagnosis.

Imaging findings of hepatic paragonimiasis : a case report

Hepatic paragonimiasis is a rare form of ectopic infestation caused by Paragonimus. We experienced a case of hepatic paragonimiasis that showed characteristic imaging findings. CT and MR images showed a cluster of small cysts with rim enhancement in the subcapsular area of the liver. This finding seems to be characteristic for hepatic paragonimiasis, considering imaging findings in paragonimiasis involving other organs.

[A case of paragonimiasis westermani with a worm migration track on chest CT]

A 59-year-old man with rusty-colored sputum was admitted for evaluation of a nodular shadow on his chest radiograph. Chest computed tomography (CT) revealed nodules and nodular opacities with a cavity in the right S3. Chest CT also showed clearly a double linear shadow other than the bronchovascular bundle, with a different course from that of the bronchovascular bundle, suggesting a worm migration track. The diagnosis of paragonimiasis westermani was confirmed by detection of Paragonimus eggs in a bronchoscopic aspirate smear and by immunoserological examination. The linear lesion on the chest CT is uncommon in paragonimiasis, but the finding is thought to be useful for the diagnosis of this disease.

Chronic cerebral paragonimiasis combined with aneurysmal subarachnoid hemorrhage

A 67-year-old Korean woman attended our hospital complaining of a severe headache. A brain computed tomography scan showed conglomerated, high-density, calcified nodules in the left temporo-occipito-parietal area and high-density subarachnoid hemorrhage in the basal cisterns. Magnetic resonance imaging of the brain shows multiple conglomerated iso- or low-signal intensity round nodules with peripheral rim enhancement. She underwent craniotomies to clip the aneurysm and remove the calcified masses. Paragonimus westermani eggs were identified in the calcified necrotic lesions. Results of parasitic examinations on the sputum and an enzyme-linked immunosorbent assay for P. westermani were all negative. The patient presented with headache and dizziness that had occurred for more than 30 years. She had not eaten freshwater crayfish or crabs. However, she had sometimes prepared raw crabs for several decades. Overall, this case was diagnosed as chronic cerebral paragonimiasis, in which she may have been infected through the contamination of utensils during the preparation of the second intermediate hosts, combined with a cerebral hemorrhage.

Pulmonary paragonimiasis mimicking lung cancer on FDG-PET imaging

The case of a 48-year-old man with pulmonary paragonimiasis mimicking lung cancer on positron emission tomography with fluorodeoxyglucose (FDG-PET) imaging is reported herein. Plain radiography and computed tomography (CT) of the chest showed a nodular lesion at the left pulmonary hilum. Lung cancer was strongly suggested from standardized uptake values determined on FDG-PET imaging; however, repeat chest CT revealed the lesion to have decreased in size. Pulmonary paragonimiasis was subsequently diagnosed after sputum microscopy demonstrated operculated parasitic eggs. To the best of our knowledge, this is the first reported case of pulmonary paragonimiasis mimicking lung cancer on FDG-PET imaging.

Pulmonary paragonimiasis misdiagnosed as tuberculosis: with special references on paragonimiasis

The diagnosis of tuberculosis by X-ray radiogram is often confused with pulmonary carcinoma, bacillary and parasitic infections, and chronic mycosis. A case of pulmonary paragonimiasis misdiagnosed as tuberculosis by X-ray radiogram is reported. With this case, the smears of sputum were rechecked by an inspection technician's discernment, and Paragonimus eggs along with numerous eosinophils and Charcot-Leyden crystals were detected. In suspected cases of tuberculosis, a history of crab-eating plus sputum examinations, image findings, and serodiagnosis are necessary to rule out paragonimiasis.

Heterotopic paragonimiasis in the omentum

Paragonimus westermani is a lung fluke but may be found in organs other than the lungs. A case of omental paragonimiasis was found incidentally by plain radiography and computed tomography and showed multiple, irregularly shaped, conglomerated calcifications in the intraperitoneum. Many P. westermani ova were detected in the resected omentum. This uncommon calcification on the plain abdominal radiography and computed tomography scan was considered to represent radiologic findings of ectopic paragonimiasis.

[A case of Paragonimiasis westermanii complicated with migrating subcutaneous induration and multiple involvements in the liver]

A 33-year-old female was admitted to a hospital with chief complaints of abdominal pain, fever, cough and migrating subcutaneous induration. She had consumed half-cooked crabs 3 months ago. On admission, a mass in the abdominal wall, pleural effusion, a nodular shadow in the right upper lung on the chest X-ray and multiple low density areas in the liver on CT. Peripheral blood examination disclosed marked eosinophilia (5,300/mm3). Although we failed to detect any parasite eggs in stool, sputum and bronchogenic secretion, the immuno-serological test for parasites revealed an infection of paragonimus. Oral administration of praziquantel resulted in the disappearance of nodular shadow in the right upper lung, multiple low density areas on CT as well as migrating subcutaneous indurations. Migration of Paragonimus westermanii larvae to liver is known to be uncommon. Thus, the present case indicates an alternate migration route of the Paragonimus westermanii in humans.

North American paragonimiasis: case report of a severe clinical infection

Paragonimiasis is an important cause of pulmonary disease worldwide. It results from an infection with Paragonimus, a parasite that reproduces through a complex life cycle involving snails, crustaceans, and mammals. Humans acquire the disease by ingesting uncooked freshwater crab or crayfish. Paragonimus species are distributed globally, and the disease is well known in endemic regions of Asia where culturally based methods of food preparation foster human transmission. Paragonimus also exists in regions of the United States but has been a rare cause of pulmonary disease. We report a case of a previously healthy young man who developed a dense empyema from Paragonimus kellicotti that ultimately required thoracotomy and praziquantel to eradicate his infection.

Case report: Paragonimiasis westermani with seroconversion from immunoglobulin (Ig) m to IgG antibody with the clinical course

A 66-year-old man visited our hospital with primary complaint of cough. Chest roentgenogram showed slight pleural effusion and pneumothorax in the left lung. Eosinophilia (22.8%) was also found in his peripheral blood. Multiple-dot enzyme-linked immunosorbent assay (dot-ELISA) for the detection of parasite-specific immunoglobulin (Ig) G antibody was used to screen his serum against various parasitic diseases, but no significant binding was observed with any of the 12 parasite antigens examined, including those of Paragonimus westermani and P. miyazakii. Although he seemed to have been spontaneously cured without treatment, a nodular shadow appeared in the right upper medial lung field on the chest roentgenogram 6 months later. This time, his serum was positive for anti-P. westermani IgG antibody by the same method. A reexamination of the first and second admission serum samples for parasite-specific IgM and IgG antibodies revealed significant level of IgM antibody in the serum of the first admission, which had decreased at the time of the second admission. Conversely, the level of IgG antibody, which was low at the first admission, became dominant in the second admission serum 6 months later. These results clearly show that although the dot-ELISA to detect IgG antibody is generally useful for screening and detecting paragonimiasis, detection of IgM antibody seems to be a useful aid and should also be included in immunoserological diagnosis, especially if the patient is considered to be in the early stage of infection.

Clinicoradiologic features of pleuropulmonary Paragonimus westermani on Kyusyu Island, Japan

STUDY OBJECTIVE

Recently, the number of new cases of Paragonimus westermani in humans has gradually increased, and paragonimiasis is a re-emerging public health issue in Kyusyu, Japan. We review our recent experience with pleuropulmonary Paragonimus westermani.

PATIENTS

Pulmonary paragonimiasis was diagnosed in 13 patients at the Third Department of Internal Medicine, Miyazaki Medical College between 1993 and 1999.

RESULTS

Both sputum and bronchoscopic examinations revealed ova in four of nine patients; bronchoscopy yielded ova in two additional patients. Twelve patients (92%) had respiratory symptoms, including cough (92%), sputum and/or hemoptysis (92%), and chest pain (46%). Chest radiography and CT showed pleural lesions (62%) and parenchymal lesions (92%). Of note was the high frequency of solitary nodular lesions (62%), mimicking lung cancer, tuberculosis, or fungal diseases. Immunodiagnosis and bronchoscopic examination were also useful for diagnosis. Praziquantel treatment was very effective and had minimal side effects. One patient required surgical decortication for empyema in spite of treatment with praziquantel. Eosinophilia was noted in peripheral blood and body fluids, which was probably due to increased levels of interleukin-5.

CONCLUSIONS

Our findings indicate that our patients with Paragonimus westermani presented with a wide variety of radiographic findings, which were different from the classic presentations reported earlier. Bronchoscopic examination and serologic tests are very useful for accurate diagnosis. As dietary habits change and international transportation increases, it appears likely that paragonimiasis will also increase in frequency in various parts of the world.

[Paragonimiasis Miyazakii with variable X-ray shadows]

A 77-year-old woman was admitted to our hospital with hemoptysis and weight loss. She had eaten 15 raw freshwater crabs about 5 months before the onset of her clinical symptoms. Chest X-ray films obtained on the first admission showed left pleural effusion. After 1 week of chemotherapy with SBTPC, the pleural effusion disappeared. Two months later, the patient was re-admitted with recurrent hemoptysis. Chest X-ray films showed a solitary nodular lesion in the right lung. Eosinophilia and increased serum IgE levels were detected. The solitary nodular lesion moved from the middle to upper field of the right lung during the patient's 3-week stay in the hospital. Serologic tests yielded a conclusive diagnosis of Paragonimiasis miyazakii infection. Praziquantel administration relieved the patient's symptoms.

Paragonimiasis westermani presenting as an asymptomatic nodular lesion in the lung: report of a case

A 57-year-old man with a history of having consumed fresh-water crab 8 months previously presented with a solitary mass lesion in the left lung without any symptoms. Since neoplastic disease could not be ruled out, an open biopsy was performed, and histological examination confirmed a definite diagnosis of paragonimiasis. A high level of the anti-Paragonimus westermani antibody was detected in the sera of the patient, but this level decreased substantially 3 months after chemotherapy with bithionol.

Tropical infection and the lung

The term "tropical lung" has been used to describe the lungs that are vulnerable to those indigenous diseases that occur with particular prevalence in tropical countries. International travel, student and cultural exchanges and changing immigration patterns are insidiously transforming the face of medicine in Europe and other developed countries. The climates of tropical countries provide an ideal environment for pathogenic organisms, and their vectors and intermediate hosts, to flourish. In an average out-patient department, 20-40% of patients have been seen with respiratory complaints, and 20-30% of hospital medical admissions are for disorders predominantly affecting the lungs. Pulmonary tuberculosis is common in tropical countries as well as the rest of the world. The other principal environmentally related tropical pulmonary diseases are melioidosis, paragonimiasis, amoebiasis, leptospirosis, gnathostomiasis and tropical eosinophilia. It is essential that the practising clinician be aware of the increasing prevalence of various new and exotic tropical lung diseases. Clinicians in developing countries can now use their clinical skills together with recent developments in immunology, molecular biology and biochemistry to improve the diagnostic accuracy and therapeutic effectiveness related to tropical lung infections. Treatment, if inappropriate, may not only be worthless but, in many cases, extremely harmful and even fatal.

Adrenal paragonimiasis simulating adrenal tumor--a case report

We describe a case of adrenal paragonimiasis with its computed tomographic and ultrasonographic findings. Computed tomogram showed a well enhancing oval mass at right adrenal gland and ultrasonogram showed a dumbbell-shaped hyperechoic mass saddling on the top of the right kidney. Surgical specimen was multicystic mass filled with creamy material.

Cerebral paragonimiasis in early active stage: CT and MR features

OBJECTIVE

Diagnosis of cerebral paragonimiasis in its early active stage is important because curative chemotherapy is possible. Accordingly, this study was undertaken to evaluate the CT and MR features of early active cerebral paragonimiasis.

MATERIALS AND METHODS

We retrospectively reviewed the CT scans (n = 29) and MR images (n = 7) of the brain in 20 patients between 7 and 59 years old who had cerebral paragonimiasis in the early active stage. The diagnosis was based on a positive antibody test by enzyme-linked immunosorbent assay (ELISA) for paragonimiasis in serum and CSF. The diagnosis was confirmed surgically in seven patients.

RESULTS

The most common and characteristic imaging finding was a conglomerate of ringlike enhancing lesions (grape-cluster appearance) with surrounding edema in one cerebral hemisphere in 11 patients (55%). Other nonspecific findings included a solitary ringlike lesion (n = 4) or irregular enhancing lesions (n = 2), localized hemorrhage with (n = 3) or without (n = 2) enhancing lesions, and a poorly defined non-hemorrhagic, nonenhancing lesion (n = 1).

CONCLUSION

CT and MR findings of clustered ring-enhancing lesions, seen in approximately half of the cases of early cerebral paragonimiasis, are suggestive of cerebral paragonimiasis.

[CT findings of pulmonary paragonimiasis westermani]

The CT findings of six patients (three symptomatic and three asymptomatic) with pulmonary paragonimiasis westermani were reviewed in correlation with the findings of radiography. Pleural changes were recognized in all cases on CT. In addition to pleural fluid collection and hydropneumothorax, which were demonstrated on plain radiograph, CT showed minimal pleural thickening and adhesion adjacent to the parenchymal lesions. CT showed round nodules of lower attenuation within a subpleural consolidation of triangular shape in two patients. Small air-filled cavities in a parenchymal lesion with central dense spots were demonstrated in two patients, and multiple cavities with irregular wall were seen in one patient. CT also demonstrated the parenchymal lesion with a tunnel-like cavity in one patient. These may represent the worm nodules, the worm within worm cysts, and the worm migration tract, respectively. These pulmonary lesions were located adjacent to the localized pleural thickening or adhesion in all six cases. CT was more useful than radiography in the diagnosis of pulmonary paragonimiasis westermani.

Pulmonary paragonimiasis: clinical and experimental studies

Pulmonary paragonimiasis is a disease caused by a lung fluke. It is endemic to East Asia, but there have been several case reports in North America. Human infestation occurs by ingestion of raw or incompletely cooked freshwater crab or crayfish infected with metacercaria. A retrospective study was performed with 78 patients who lived in South Korea and had chest radiographic findings of pleuropulmonary disease; it was subsequently shown that they had paragonimiasis. The diagnosis was based on positive results of serologic tests for Paragonimus-specific antibody or on the detection of eggs in sputum samples. Radiologic findings from these 78 patients were correlated with the pathologic and radiologic findings from a study of experimentally induced pulmonary paragonimiasis in 21 cats. Findings from the correlative study document that the typical radiologic manifestations of pulmonary paragonimiasis vary with the stage of the disease. Early findings include pneumothorax or hydropneumothorax, focal airspace consolidation, and linear opacities and are caused by the migration of juvenile worms. Later findings include thin-walled cysts, dense masslike consolidation, nodules, or bronchiectasis and are due to worm cysts.

Paragonimus calcified ova mimicking left renal staghorn stone

We report on a 49-year-old woman with clusters of Paragonimus calcified ova unusually located in the left retroperitoneal space and renal capsule mimicking a left renal staghorn stone. The diagnosis and treatment are discussed. We also reviewed the endemic condition of paragonimiasis in Taiwan.

Pulmonary paragonimiasis simulating lung abscess in a 9-year-old: CT findings

We present the CT findings of pulmonary paragonimiasis in a 9-year-old girl. It appeared as a large cystic mass with an air-fluid level and simulated a lung abscess. Communication with a segmental bronchus was demonstrated well on a CT scan obtained after aspiration.

Pleuropulmonary paragonimiasis: radiologic findings in 71 patients

Pleuropulmonary paragonimiasis is a disease caused by lung flukes characterized by migration of a juvenile worm in the early stage and by formation of cysts around the worm later on. The purpose of this study was to describe the radiologic manifestations of pleuropulmonary paragonimiasis, with special emphasis on the worm cyst and worm migration track. We retrospectively studied 71 patients who had evidence of pleuropulmonary paragonimiasis on chest radiographs (n = 71) and CT scans (n = 17). The diagnosis was based on the detection of eggs or on positive antibody tests. On chest radiographs, 59 patients (83%) had pulmonary lesions and 43 patients (61%) had pleural lesions. Pulmonary findings included patchy air-space consolidation (n = 37) with or without cystic changes; ring shadows (n = 16); and peripheral linear opacities (n = 29), which were more prominent in patients with pleural effusion. Twelve patients (17%) had bilateral pleural effusions or pneumothoraces. On CT scans, round low-attenuation cystic lesions (5-15 mm), filled either with fluid (n = 5) or gas (n = 5), were characteristically seen within the consolidation. Peripheral linear opacities seen on radiographs were suggestive of worm migration tracks on CT scans. CT may reveal an intracystic worm. Although the findings vary depending on the stage of the disease, findings on chest radiographs are usually typical of paragonimiasis. CT provides more specific information about the worm cyst and the worm migration track.

Pleuropulmonary paragonimiasis in a Laotian immigrant to Australia

A case of pleuropulmonary paragonimiasis that mimicked reactivation of pulmonary tuberculosis, pneumonia, and neoplasm occurred in a Laotian immigrant to Australia. The key to the diagnosis of this condition is awareness of the disease in persons from this region. The diagnosis was supported by enzyme-linked immunosorbent assay testing. The patient was successfully treated with praziquantel.

Cerebral paragonimiasis--report of five cases

Five cases of cerebral paragonimiasis presenting with hemianopsia, convulsion, and gait disturbance are discussed. The cases were all in the chronic stage. The intradermal paragonimiasis reaction, complement fixation, and Ouchterlony tests were not useful for diagnosis. Computed tomography demonstrated calcifications in all cases in sites consistent with the foci of symptoms. Surgical treatment in two cases failed to improve symptoms.

[CT findings in "fresh" cerebral paragonimiasis]

There are few reports on CT findings in "fresh" cerebral paragonimiasis. We have experienced four cases of "fresh" cerebral paragonimiasis examined by CT scan. Three patients were children aged 7, 9, and 14 years, and one was an adult aged 25 years. Three patients were examined by CT scan 2 to 6 months after the onset of high grade fever, convulsion and focal deficit signs, and a patient was examined one month after his progressive visual disturbance. The unique CT findings are multilocular cystic lesions in temporo-occipital or in temporo-parietal lobes with extensive brain edema. Two cases were also associated with "soap-bubble" calcifications. The cysts were more dense than CSF and enhanced by contrast media. The histopathological specimen showed that the eggs of paragonimus were in the abscess cavity, of which the wall was composed with highly vascular gliomesenchymal capsule and numerous cell infiltration. Three patients underwent craniotomy for removal of abscess and decompression. Bitionol were administered and all patients recovered well. We also discussed the differential diagnosis of cerebral parasitic granulomas.

[Clinico-roentgenologic manifestations of larval paragonimiasis in children]

Investigation of 60 children with acute types and 45 children with latent types of larval paragonimiasis (LP) has revealed various clinical and x-ray manifestations of this disease, spread in the southern Primorski Territory. Three syndromes of this disease were singled out: toxico-allergic, abdominal and pulmonary. X-ray investigation showed characteristic LP symptoms: exudate in the pleural cavity, thickening of the wall, diaphragmatic and interlobular pleura, sometimes--pneumothorax. Pathology of the bronchopulmonary system manifested itself in focal and infiltrative shadows, enhanced and deformed lung markings, and bullous inflation. Diagnosis and differential diagnosis must be based on analysis of clinical and x-ray data and the results of serological reactions.

[Clinical and radiologic manifestations of larval paragonimiasis in children]

Investigation of 60 children with acute types and 45 children with latent types of larval paragonimiasis (LP) has revealed various clinical and x-ray manifestations of this disease, spread in the southern Primorski Territory. Three syndromes of this disease were singled out: toxico-allergic, abdominal and pulmonary. X-ray investigation showed characteristic LP symptoms: exudate in the pleural cavity, thickening of the wall, diaphragmatic and interlobular pleura, sometimes--pneumothorax. Pathology of the bronchopulmonary system manifested itself in focal and infiltrative shadows, enhanced and deformed lung markings, and bullous inflation. Diagnosis and differential diagnosis must be based on analysis of clinical and x-ray data and the results of serological reactions.

CT findings of cerebral paragonimiasis in the chronic state

The CT findings in 5 patients with cerebral paragonimiasis in the chronic state are presented. The findings were: 1) multiple, densely calcified areas with a variety of round or nodular shapes in the brain, 2) a large low density area surrounding or connecting with the calcified areas, and 3) cortical atrophy and ventricular dilatation. The relation between the CT findings and the previously reported plain skull X-ray findings or neuropathological findings are discussed.