HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:
Guest Access | Sign In via User Name/Password

This Article Abstract Full Text (PDF) Free Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Add to My Personal Article Archive Download to citation manager Citing Articles Citing Articles via ISI Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Jeon, K. Articles by Han, J. Search for Related Content PubMed PubMed Citation Articles by Jeon, K. Articles by Han, J.

Clinical Features of Recently Diagnosed Pulmonary Paragonimiasis in Korea^*

^* From the Division of Pulmonary and Critical Care Medicine, Department of Medicine (Drs. Jeon, Koh, H. Kim, and Kwon), Department of Radiology (Drs. T.S. Kim and Lee), and Department of Pathology (Dr. Han), Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.

Correspondence to: Won-Jung Koh, MD, Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-ku, Seoul 135–710, South Korea; e-mail: wjkoh{at}smc.samsung.co.kr

	Abstract

TOP Abstract Introduction Materials and Methods Results Discussion References

 
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.

Key Words: diagnosis • differential diagnosis • Korea • paragonimiasis

	Introduction

TOP Abstract Introduction Materials and Methods Results Discussion References

 
Pulmonary paragonimiasis is a parasitic disease of the lung, and is caused by infestation with Paragonimus westermani lung flukes, or other species of Paragonimus.¹²³ Human infection occurs by ingestion of infectious Paragonimus metacercariae within freshwater crab or crayfishes. These metacercariae exist in the small intestine, and pass through the intestinal wall, peritoneal cavity, diaphragm, and pleural cavity to finally enter the lung parenchyma, where they mature to adult flukes.¹²³ Therefore, the disease is common in limited areas of Asia such as China, Korea, Japan, the Philippines, and Taiwan, some part of Latin America, and Africa, where the people habitually eat raw or undercooked freshwater crab or crayfishes.^{12345678910111213} Also, P westermani infection occurs in humans via the ingestion of raw meat of the wild boar, a paratenic host, as "sashimi"; this pathway of infection appears to be occurring with increasing frequency in Japan.⁷¹⁴ Recently, however, patients with paragonimiasis have been seen in almost every location in the world, due to increases in the numbers of immigrants and overseas travelers, the popularization of ethnic dishes in developed countries, and the expansion of worldwide food trading.^151617181920 These reports have served to remind physicians that paragonimiasis must now be considered in the differential diagnosis of pulmonary diseases, even in Western countries.

The classic symptoms of pulmonary paragonimiasis include a chronic cough with rusty-brown sputum, hemoptysis, pleurisy, and fever with radiographic findings of patchy density, linear infiltration, nodules, pleural effusion, and pulmonary cavities.^145212223 As these clinical manifestations are so similar to those of tuberculosis, many paragonimiasis patients are initially treated for tuberculosis.^4151624 Reports from Japan,^625262728 as distinct from those in the past, asserted that paragonimiasis has become more prevalent among middle-aged patients, and frequently refer to observed nodular lesions on chest radiography. These patients are often suspected by clinicians to have lung cancer.^625262728 In such cases, when paragonimiasis is misdiagnosed as tuberculosis or lung cancer, patients suffer from the considerable burden associated with long-term hospitalization, as well as unnecessary diagnostic procedures and treatments.

In South Korea, known to be an area where P westermani is endemic, the incidence of the disease has recently decreased, due to improvements in public health and changes in dietary habits. Survey data taken in the 1990s indicated that the prevalence of paragonimiasis has decreased to approximately 1% of that seen in the early 1970s.²⁹ However, at least 10% of freshwater crabs sold in local markets are infected with the metacercariae of P westermani.²⁹ We have continuously observed clinical cases of pulmonary paragonimiasis due to the persisting tradition in a small sector of the population of eating freshwater crustaceans. Many of the patients in such cases were initially suspected to have pulmonary tuberculosis or lung cancer. We retrospectively analyzed the cases of patients with pulmonary paragonimiasis diagnosed during the most recent 10 years in order to determine whether the clinical and radiologic features of these recent cases had changed from the classic presentations reported in previous studies.

	Materials and Methods

TOP Abstract Introduction Materials and Methods Results Discussion References

 
All 36 patients who had received a diagnosis of pulmonary paragonimiasis at the Samsung Medical Center (Seoul, South Korea) from October 1994 to September 2004 were included in the present study. Patients with associated pulmonary tuberculosis or lung cancer were excluded from the study. Twenty-one of the patients were men, and 15 were women. Their ages ranged from 19 to 75 years (median, 48 years). The diagnoses were based on positive serologic test results for Paragonimus-specific antibody, or on the detection of characteristic Paragonimus eggs in sputum, bronchial washing fluid, or lung biopsy specimens.

The enzyme-linked immunosorbent assay (ELISA) test, an immunoserologic test for Paragonimus-specific IgG antibody, was performed on samples from 29 patients (81%).³⁰ Sputum cytology examinations for the detection of eggs were performed in 26 patients (72%). Bronchoscopies were performed in 13 patients (36%). Lung biopsies were performed in 10 patients (28%). Transbronchial lung biopsies were performed in five patients, fluoroscopy-guided percutaneous transthoracic lung biopsies in three patients, and surgical lung biopsies in two patients.

The medical records were reviewed for information related to the clinical data of the patients, including symptoms, history of eating raw or undercooked freshwater crab or crayfishes, laboratory tests, and other diagnostic procedures. The chest radiographs of all patients were reviewed. Abnormal findings in the chest radiographs were classified into two types⁴⁵: intrapulmonary parenchymal lesions, such as airspace consolidation, nodular, linear, and cystic opacity; and pleural lesions, including pleural effusion, pneumothorax, and hydropneumothorax.

All patients were treated with high doses of praziquantel, 75 mg/kg/d for 2 days. Praziquantel treatment resulted in the resolution of respiratory symptoms and abnormal chest radiography findings in all patients except three, all of whom were transferred to other institutions, usually their referring institutions, after paragonimiasis was diagnosed.

	Results

TOP Abstract Introduction Materials and Methods Results Discussion References

 
Clinical Features
The clinical and laboratory data of the patients are summarized in Table 1 . Thirty-four patients (94%) presented with respiratory symptoms, including hemoptysis (n = 20, 56%), cough (n = 17, 47%), dyspnea (n = 8, 22%), chest pain (n = 5, 14%), fever (n = 5, 14%), and purulent sputum (n = 2, 6%). Two patients (6%) were asymptomatic, but the disease was discovered by abnormal chest radiography findings during preoperative check-ups for orthopedic surgery or general health examinations. The apparent duration of illness, which was available in 32 of the patients’ medical records, ranged from 1 week to 26 months (median, 4 months). Seventeen patients (47%) had a history of eating freshwater crustaceans, especially freshwater crabs pickled in soybean sauce (kejang) in Korea. Eleven patients (31%) denied such an eating history. In the remaining eight patients (22%), the medical record with regard to eating history was not available. Leukocytosis of the peripheral blood (> 10,000/µL) was seen in 10 patients (28%), and the WBC counts were within normal range in 26 patients (72%). Eosinophilia (> 500/µL) was detected in the peripheral blood of 25 patients (69%), and the degree of eosinophilia was median 14% (range, 10 to 66%) in these 25 patients.

Radiologic Features
The patients presented with a variety of radiologic findings (Table 2 ). Thirty-three of 36 patients (92%) displayed abnormal chest radiographic findings. The remaining three patients (8%) were found to have no radiographic abnormalities.

View larger version (129K): [in this window] [in a new window] [Download PPT slide]   Figure 1.. Intrapulmonary parenchymal lesions and pleural lesions on chest radiographs of pulmonary paragonimiasis patients. Top left, A: Chest radiograph of 44-year-old man showing nodular lesions in the left upper lung zone. Top center, B: Chest radiographs of 61-year-old man showing linear opacity in the right lower lung zone. Top right, C: Chest radiograph of 48-year-old man showing airspace-consolidation in the right upper lung zone. Bottom left, D: Chest radiograph of 58-year-old man showing cystic opacity in the left middle lung zone. Bottom center, E: Chest radiograph of 44-year-old woman showing pleural effusion in the left lung. Bottom right, F: Chest radiograph of 52-year-old man showing pneumothorax-associated pleural effusion in the right lung.

Confirmative Diagnosis of Paragonimiasis
The confirmative diagnosis of paragonimiasis was based on the positive result of an ELISA test (n = 28, 78%), or by the identification of characteristic Paragonimus eggs in sputum samples, bronchial washing fluid, or lung biopsy specimens (n = 14, 39%). Six patients (17%) had positive results on both an ELISA test and the examination for Paragonimus eggs in cytologic or pathologic specimens.

Paragonimus eggs were detected in the sputum of 12 patients (46%) of the 26 patients in whom sputum examinations were conducted. Lung biopsies were performed in the 10 patients initially suspected of having lung cancer based on clinical and radiologic findings (nodular opacity in 9 patients, mass-like consolidation in 1 patient). Histopathologic diagnoses of paragonimiasis were confirmed by identification of Paragonimus eggs in four patients via percutaneous transthoracic lung biopsy (n = 2) or surgical lung biopsy (n = 2) [Fig 2 ]. In the remaining six patients, parasite eggs could not be identified in the lung tissues.

View larger version (42K): [in this window] [in a new window] [Download PPT slide]   Figure 2.. Seventy-nine-year-old woman with pulmonary paragonimiasis. Chest CT of the patient showed a 24-mm central nodule in the anterior segment of the right upper lobe Left, A with associated partial atelectasis of the right upper lobe. Center, B: The photomicrograph shows multiple P westermani eggs in the wall of a granuloma. Note the multiple eosinophils in the granuloma wall Right, C (hematoxylin-eosin, original x 40).

View larger version (77K): [in this window] [in a new window] [Download PPT slide]   Figure 3.. Bronchoscopic appearance and histologic finding of bronchial mucosal biopsy specimens in 61-year-old man with pulmonary paragonimiasis. Top, A: Fiberoptic bronchoscopy revealed bronchial narrowing, associated with mucosal edema of the segmental bronchi of the left upper lobe. Bottom, B: Photomicrograph of bronchial tissue obtained from the left upper lobar bronchus evidenced thickening of basement membrane and chronic inflammation with eosinophilic infiltration (hematoxylin-eosin, original x 400).

	Discussion

TOP Abstract Introduction Materials and Methods Results Discussion References

Typical pulmonary paragonimiasis patients exhibit fever, chest pain, and respiratory symptoms, including a chronic cough with hemoptysis.²¹ The main determinants of clinical manifestation are number of infecting parasites, their location, and the stage of the infection.⁴²³ The spectrum of pulmonary paragonimiasis ranges from asymptomatic, to overt and serious disease in cases of heavy infection. Fever has been noted in 10 to 20% of patients during the lung phase, and two thirds of patients may experience occasional febrile episodes over the entire course of the disease.⁴²⁴ Chest pain, considered to be due to pleurisy, was generally reported in approximately 40 to 60% of cases in the previous studies.⁴⁵²⁴ However, the disease runs a chronic course, persisting from a few weeks to several years.⁴ According to Japanese studies,⁶²⁵ fever and chest pain are less frequently observed than other respiratory symptoms, which is consistent with our observation. This is probably the result of low-density infections. Due to its nonspecific manifestations, its chronic and mild course, and the low recall rate of freshwater crustacean ingestion, a correct initial diagnosis was made in only 8% of our patients.

The most common symptom was hemoptysis (56%) in the present study. The etiology for hemoptysis varies among different series according to time of publication, the geographic location, and the diagnostic tests employed. Bronchitis, bronchogenic carcinoma, and bronchiectasis are the most common causes of hemoptysis depending on the patient population studied in recently published literatures, although tuberculosis was reported as a most important cause of hemoptysis in older articles and even more recent reports from some developing countries.^31323334 Based on our study results, pulmonary paragonimiasis should be considered as a possibility in the differential diagnosis when hemoptysis has developed in a patient who has lived or has traveled to paragonimiasis endemic areas.

Peripheral blood examinations allow the detection of leukocytosis and eosinophilia in many patients with pulmonary paragonimiasis.⁴⁷²³ In our study, 28% of patients exhibited leukocytosis, and 69% exhibited eosinophilia. Previous studies⁴⁶¹⁵²⁴ reported that peripheral blood eosinophilia was observed in > 80% of paragonimiasis patients. Eosinophilia is observed only when the worms are alive and migrating.⁴ It disappears when the disease moves into its chronic phase.⁴ The degree of eosinophilia also varies from patient to patient. Japanese investigators²⁵ reported that the degree of peripheral blood eosinophilia was significantly higher in patients with pleurisy than in patients with parenchymal lesions, indicating that eosinophilia was an acute-phase response of the host. In other words, at least some patients, especially those exhibiting parenchymal lesions, have normal eosinophilia counts in their peripheral blood. Thus, although eosinophilia is an important parameter in the suspicion of paragonimiasis at the early stages of infection, a lack of eosinophilia does not necessarily rule out the possibility of paragonimiasis.⁷

Pleural fluid eosinophilia, whose causes are malignancy or tuberculosis as well as pneumothorax or hemothorax,³⁵ is reported with a high incidence in patients with paragonimiasis.^15363738 Although a small number of patients had pleural effusion in this series, pleural fluid eosinophilia, as well as a low pH, was detected in 60% of patients with pleural effusion. In addition, all patients had pleural fluid with a low glucose level and a high lactate dehydrogenase level. Based on our experience and the previous reports, characteristic pleural fluid findings can be a very helpful clue in the diagnosis of pulmonary paragonimiasis.

Radiographically, pulmonary paragonimiasis can manifest in a host of ways, ranging from an absolutely normal chest radiograph to diffuse infiltrates with bilateral hydropneumothorax.⁴⁷²³ This is, presumably, dependent on which stage in the development of the disease has been currently reached.⁴⁷²³ In the previous reports, the most common manifestation observed was pleural lesions. These ranged from simple pleural thickening, to bilateral hydropneumothorax. For example, Johnson et al¹⁵ reported that five of nine paragonimiasis patients among immigrants in the United States exhibited pleural effusion. Subsequently, the researchers¹⁶ evaluated more cases, and reported that 48% of those cases involved pleural effusion. In addition, according to a host of reports⁶²⁵³⁹ from Japan and Korea, nearly 70% of paragonimiasis patients exhibit pleural lesions. In our series, however, pleural lesions were relatively rare (28%). Also, the frequency of intrapulmonary parenchymal lesions was high (72%) compared to the reports of previous studies. In particular, a nodular opacity of variable diameter (median, 2.7 cm; range, 1.5 to 4.0 cm) was the most common (54%) parenchymal lesion in our study, reported by previous studies⁴⁵¹⁶²⁴ to be observed in 8 to 25% of cases. The radiographic findings vary with the stage of the disease.⁵³⁹ Early findings include pneumothorax or hydropneumothorax, focal airspace consolidation, and linear opacities.⁵³⁹ Later findings include thin-walled cysts, dense mass-like consolidation, nodules, or bronchiectasis.⁵³⁹ This suggests that the patients in our study may have been in a later stage of paragonimiasis.

Until recently, distinguishing between paragonimiasis and tuberculosis has frequently proven to be quite difficult, and constitutes a diagnostic dilemma in areas in which tuberculosis and paragonimiasis coexist.⁵⁴⁰ For example, Singh and colleagues²⁴ reported that 59% of their patients initially received a diagnosis of tuberculosis. Johnson and associates¹⁵ reported that 68% were receiving antituberculosis therapy. Shim and coworkers⁴ also reported that tuberculosis was diagnosed in 46% before the final diagnosis of pulmonary paragonimiasis was made. Our results were similar to those of others. Thirty percent of our patients had received a tentative diagnosis of pulmonary tuberculosis on their initial visit. Nowadays, however, differentiation between paragonimiasis and lung cancer represents a diagnostic dilemma, even in areas where paragonimiasis is enemic.^6262728 Twenty-eight percent of our pulmonary paragonimiasis patients were presumed to have had lung cancer on their initial visit. These results emphasized the necessity of generating awareness among clinicians about the inclusion of paragonimiasis in the differential diagnosis of lung cancer, as well as tuberculosis.

Only a few reports have addressed the issue of endobronchial lesions in pulmonary paragonimiasis patients. Mukae et al⁶ reported bronchial stenosis in seven of nine patients (78%) who had undergone bronchoscopy. Our results indicated bronchial luminal narrowing, with congested or edematous mucosal changes, in 7 of 13 patients (54%), and these results were consistent with those of the previous study.⁶ In addition, bronchial mucosal biopsy specimens exhibited chronic inflammation with eosinophilic infiltrations in three of these seven patients (43%) in our study. To our best knowledge, no previous studies have demonstrated chronic eosinophilic inflammation in bronchial mucosal biopsy specimens, although no parasite eggs could be found in the specimens obtained from these lesions in our study. Im et al³⁹ reported a variety of radiographic findings in 78 patients with pulmonary paragonimiasis, and bronchiectasis was observed on the chest CT scans of 6 of 17 patients. They also reported that the juvenile worms tent and settle adjacent to the small airways, forming worm cysts. Furthermore, connection of these worm cysts with the airways occurred uniformly in 21 cats with experimentally induced pulmonary paragonimiasis.³⁹ Im et al³⁹ suggested that prolonged bronchial inflammation, and mechanical injury of the bronchi by intrabronchial worms, may contribute to the development of bronchiectasis. Our results, combined with those of previous studies,⁶³⁹ indicate that P westermani infection results in an inflammation of the bronchi, culminating in bronchial stenosis or focal bronchiectasis.

Our study was done at a tertiary care center. Therefore, our study population was not representative of the general population of pulmonary paragonimiasis sufferers. Most of our patients were referred for differentiation of other pulmonary disease, usually lung cancer or tuberculosis. Therefore, it may be that the classic presentations of pulmonary paragonimiasis had simply been more easily diagnosed at outside hospitals, and the patients were never referred to the tertiary care center. Nevertheless, our findings were not dissimilar from a Japanese report⁶ that was conducted at a referral center for parasite disease.

In conclusion, our pulmonary paragonimiasis patients presented with a variety of clinical and radiologic findings, which in some cases mimicked those of lung cancer or tuberculosis, in a manner dissimilar to the classic presentations reported earlier. Paragonimiasis requires specific chemotherapy, resulting in immediate improvement. Correct differential diagnosis is, therefore, quite important. When a pulmonary nodular or mass lesion is detected in a patient who has lived in or traveled to paragonimiasis-endemic areas, paragonimiasis should always be included in the differential diagnosis of lung diseases. Pulmonary paragonimiasis will inevitably be encountered more frequently by physicians in various parts of the world, due to increasing numbers of immigrants and overseas travelers, and changes in global dietary patterns.

	Footnotes

 
Abbreviation: ELISA = enzyme-linked immunosorbent assay

This work was supported by grant R11–2002-103 from the Korea Science and Engineering Foundation.

Received for publication December 2, 2004. Accepted for publication January 24, 2005.

	References

TOP Abstract Introduction Materials and Methods Results Discussion References

 

1. Yokogawa, M (1969) Paragonimus and paragonimiasis. Adv Parasitol 7,375-387[Medline]
2. Sadun, EH, Buck, AA Paragonimiasis in South Korea: immunodiagnostic, epidemiologic, clinical, roentgenologic and therapeutic studies. Am J Trop Med Hyg 1960;9,562-599[Abstract/Free Full Text]
3. Choi, DW Paragonimus and paragonimiasis in Korea. Kisaengchunghak Chapchi 1990;28(suppl),79-102[Medline]
4. Shim, YS, Cho, SY, Han, YC Pulmonary paragonimiasis: a Korean perspective. Semin Respir Med 1991;12,35-45
5. Im, JG, Whang, HY, Kim, WS, et al Pleuropulmonary paragonimiasis: radiologic findings in 71 patients. AJR Am J Roentgenol 1992;159,39-43[Abstract/Free Full Text]
6. Mukae, H, Taniguchi, H, Matsumoto, N, et al Clinicoradiologic features of pleuropulmonary Paragonimus westermani on Kyusyu Island, Japan. Chest 2001;120,514-520[Abstract/Free Full Text]
7. Nakamura-Uchiyama, F, Mukae, H, Nawa, Y Paragonimiasis: a Japanese perspective. Clin Chest Med 2002;23,409-420[CrossRef][ISI][Medline]
8. Miyazaki, I, Grados, O Occurrence of the lung fluke, Paragonimus caliensis, in Peru. J Parasitol 1972;58,1210-1211[CrossRef][Medline]
9. Alarcon de Noya, B, Noya, O, Torres, J, et al A field study of paragonimiasis in Venezuela. Am J Trop Med Hyg 1985;34,766-769[ISI][Medline]
10. Velez, ID, Ortega, JE, Velasquez, LE Paragonimiasis: a view from Columbia. Clin Chest Med 2002;23,421-431,ix-x[CrossRef][ISI][Medline]
11. Nwokolo, C Outbreak of paragonimiasis in Eastern Nigeria. Lancet 1972;1,32-33[CrossRef][ISI][Medline]
12. Cabaret, J, Bayssade-Dufour, C, Tami, G, et al Identification of African Paragonimidae by multivariate analysis of the eggs. Acta Trop 1999;72,79-89[CrossRef][ISI][Medline]
13. Moyou-Somo, R, Kefie-Arrey, C, Dreyfuss, G, et al An epidemiological study of pleuropulmonary paragonimiasis among pupils in the peri-urban zone of Kumba town, Meme Division, Cameroon. BMC Public Health 2003;3,40[CrossRef][Medline]
14. Uchiyama, F, Morimoto, Y, Nawa, Y Re-emergence of paragonimiasis in Kyushu, Japan. Southeast Asian J Trop Med Public Health 1999;30,686-691[Medline]
15. Johnson, JR, Falk, A, Iber, C, et al Paragonimiasis in the United States: a report of nine cases in Hmong immigrants. Chest 1982;82,168-171[Abstract/Free Full Text]
16. Johnson, RJ, Johnson, JR Paragonimiasis in Indochinese refugees: roentgenographic findings with clinical correlations. Am Rev Respir Dis 1983;128,534-538[ISI][Medline]
17. Sharma, OP The man who loved drunken crabs: a case of pulmonary paragonimiasis. Chest 1989;95,670-672[Free Full Text]
18. Mukerjee, CM, Simpson, SE, Bell, RJ, et al Pleuropulmonary paragonimiasis in a Laotian immigrant to Australia. Chest 1992;101,849-851[Abstract/Free Full Text]
19. Guiard-Schmid, JB, Lacombe, K, Osman, D, et al Paragonimiasis: a rare little known disease. Presse Med 1998;27,1835-1837[ISI][Medline]
20. Yee, B, Hsu, JI, Favour, CB, et al Pulmonary paragonimiasis in Southeast Asians living in the central San Joaquin Valley. West J Med 1992;156,423-425[ISI][Medline]
21. Chang, HT, Wang, CW, Yu, CF, et al Paragonimiasis: a clinical study of 200 adult cases. Chin Med J 1958;77,3-9[Medline]
22. Nana, A, Bovornkitti, S Pleuropulmonary paragonimiasis. Semin Respir Med 1991;12,46-54
23. Kagawa, FT Pulmonary paragonimiasis. Semin Respir Infect 1997;12,149-158[Medline]
24. Singh, TS, Mutum, SS, Razaque, MA Pulmonary paragonimiasis: clinical features, diagnosis and treatment of 39 cases in Manipur. Trans R Soc Trop Med Hyg 1986;80,967-971[CrossRef][ISI][Medline]
25. Nakamura-Uchiyama, F, Onah, DN, Nawa, Y Clinical features of paragonimiasis cases recently found in Japan: parasite-specific immunoglobulin M and G antibody classes. Clin Infect Dis 2001;32,e151-153[CrossRef][ISI][Medline]
26. Yoshino, I, Nawa, Y, Yano, T, et al Paragonimiasis westermani presenting as an asymptomatic nodular lesion in the lung: report of a case. Surg Today 1998;28,108-110[CrossRef][ISI][Medline]
27. Tomita, M, Matsuzaki, Y, Nawa, Y, et al Pulmonary paragonimiasis referred to the department of surgery. Ann Thorac Cardiovasc Surg 2000;6,295-298[Medline]
28. Watanabe, S, Nakamura, Y, Kariatsumari, K, et al Pulmonary paragonimiasis mimicking lung cancer on FDG-PET imaging. Anticancer Res 2003;23,3437-3440[ISI][Medline]
29. Cho, SY, Kong, Y, Kang, SY Epidemiology of paragonimiasis in Korea. Southeast Asian J Trop Med Public Health 1997;28(suppl),32-36[Medline]
30. Cho, SY, Hong, ST, Rho, YH, et al Application of micro-ELISA in serodiagnosis of human paragonimiasis. Korean J Parasitol 1981;19,151-156[Medline]
31. Johnston, H, Reisz, G Changing spectrum of hemoptysis: underlying causes in 148 patients undergoing diagnostic flexible fiberoptic bronchoscopy. Arch Intern Med 1989;149,1666-1668[Abstract]
32. Santiago, S, Tobias, J, Williams, AJ A reappraisal of the causes of hemoptysis. Arch Intern Med 1991;151,2449-2451[Abstract]
33. Hirshberg, B, Biran, I, Glazer, M, et al Hemoptysis: etiology, evaluation, and outcome in a tertiary referral hospital. Chest 1997;112,440-444[Abstract/Free Full Text]
34. Domoua, K, N'Dhatz, M, Coulibaly, G, et al Hemoptysis: main etiologies observed in a pneumology department in Africa. Rev Pneumol Clin 1994;50,59-62[Medline]
35. Adelman, M, Albelda, SM, Gottlieb, J, et al Diagnostic utility of pleural fluid eosinophilia. Am J Med 1984;77,915-920[CrossRef][ISI][Medline]
36. Minh, VD, Engle, P, Greenwood, JR, et al Pleural paragonimiasis in a Southeast Asia refugee. Am Rev Respir Dis 1981;124,186-188[ISI][Medline]
37. Romeo, DP, Pollock, JJ Pulmonary paragonimiasis: diagnostic value of pleural fluid analysis. South Med J 1986;79,241-243[ISI][Medline]
38. Taniguchi, H, Mukae, H, Matsumoto, N, et al Elevated IL-5 levels in pleural fluid of patients with paragonimiasis westermani. Clin Exp Immunol 2001;123,94-98[CrossRef][ISI][Medline]
39. Im, JG, Kong, Y, Shin, YM, et al Pulmonary paragonimiasis: clinical and experimental studies. Radiographics 1993;13,575-586[Abstract]
40. Narain, K, Devi, KR, Mahanta, J Pulmonary paragonimiasis and smear-negative pulmonary tuberculosis: a diagnostic dilemma. Int J Tuberc Lung Dis 2004;8,621-622[ISI][Medline]

This Article Abstract Full Text (PDF) Free Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Add to My Personal Article Archive Download to citation manager Citing Articles Citing Articles via ISI Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Jeon, K. Articles by Han, J. Search for Related Content PubMed PubMed Citation Articles by Jeon, K. Articles by Han, J.