North American paragonimiasis. A case report

BACKGROUND: Paragonimiasis is a parasitic infection with a predilection for pulmonary involvement. Paragonimus species occur throughout the world and exist in nature in a snail-crustacean-mammalian life cycle. Human disease is most frequently encountered in cultures that ingest raw or undercooked crustaceans. North American paragonimiasis, caused by an endemic Paragonimus species, Paragonimus kellicotti, predominantly causes disease in carnivorous and omnivorous animals but may cause human disease if the intermediate host, the crayfish, is ingested raw or undercooked. CASE: A previously healthy, 21-year-old male was infected with P kellicotti and developed parasitic hemoptysis. The disease was contracted through the ingestion of local, undercooked crayfish. Diagnosis was established through the morphologic examination of eggs in the cytologic preparation of bronchioalveolar lavage fluid. The patient was successfully treated with praziquantel and recovered without incident. CONCLUSION: Paragonimiasis is a cause of parasitic hemoptysis worldwide. Paragonimiasis is infrequently encountered in North America and is usually not considered in the differential diagnosis of hemoptysis unless specific risk factors are known. The cytologist or cytopathologist, therefore, may be the first to encounter the diagnostic eggs and should be familiar with this disease.     

A paragonimiasis patient with allergic reaction to praziquantel and resistance to triclabendazole: successful treatment after desensitization to praziquantel

Paragonimiasis is an infectious disease caused by trematodes of the genus Paragonimus. This trematode can be treated successfully with praziquantel in more than 90% of the cases. Although praziquantel is generally well tolerated, anaphylactic reactions to this drug have been reported in a few cases. We report here a 46-year-old Korean female with paragonimiasis, presumed to be due to Paragonimus westermani, who displayed an allergic reaction to praziquantel and resistance to triclabendazole treatment. The patient was successfully treated with praziquantel following a rapid desensitization procedure. Desensitization to praziquantel could be considered when no alternative drugs are available.     

Human paragonimiasis in Viet Nam: epidemiological survey and identification of the responsible species by DNA sequencing of eggs in patients' sputum

Parasitological and sero-epidemiological surveys for human paragonimiasis were conducted in three provinces of Viet Nam. A total of 590 participants from two known endemic areas of human paragonimiasis (Sinho district of Laichau province and Lucyen district of Yenbai province) and from Dakrong district of Quangtri province where we recently found crab hosts heavily infected with Paragonimus westermani metacercariae. By multiple dot-ELISA screening, 28 (12.7%) out of 220 participants in Sinho district of Laichau province and 4 (3.3%) out of 120 participants in Lucyen district of Yenbai province were proven to be antibody-positive against the Paragonimus antigen. None of the 250 sera of the residents in Dakrong, Quangtri province, gave sero-positivity. Among a total of 32 sero-positive patients Paragonimus eggs were found in 6 cases. ITS2 sequences were successfully determined from a single Paragonimus egg from each patient. The results of homology search by BLAST and alignment clearly confirmed that Paragonimus eggs collected from 6 patients were all of Paragonimus heterotremus. The pathogenicity of P. westermani for human paragonimiasis in Viet Nam is still questionable and needs to be explored in the future.     

Distribution and clinical features of Paragonimiasis skrjabini in Three Gorges Reservoir Region

Paragonimiasis has previously been reported in the Southwest Provinces of China, including Chongqing and Sichuan. The construction of Three Gorges Dam, which was begun in 1994, has resulted in substantial changes to the depth and the flow pattern of the Yangtze River. To investigate epidemiology of the paragonimiasis, 724 people aged 2-49years were selected and examined for Paragonimus infection by intradermal test (IDT), and enzyme-linked immunosorbent assay (ELISA). A survey of eating habits was conducted face-to-face in 5 endemic counties. Freshwater crabs were collected from seven sites in the 5 counties to determine the rate of infection with Paragonimus metacercariae. Additionally, we analyzed 213 case reports from the region dated 2006 to 2009. According to the survey results, the prevalence of Paragonimus skrjabini infection in freshwater crab was 39.65%, and the human infection rates detected by IDT and ELISA were 14.36% (104/724) and 7.46% (54/724), respectively. These results show that the Three Gorges Reservoir is still an area of high paragonimiasis endemicity. The water level of the Yangtze River has risen to 175m, and the area of water coverage in the region has increased to 1084km(2). These conditions will favor the growth and expansion of the freshwater crab population.     

Skin test for paragonimiasis among schoolchildren and villagers in Namback District, Luangprabang Province, Lao PDR

As a part of a broader effort to determine the status of Paragonimus species infection in Lao PDR, an epidemiological survey was conducted on villagers and schoolchildren in Namback District between 2003 and 2005. Among 308 villagers and 633 primary and secondary schoolchildren, 156 villagers and 92 children evidenced a positive reaction on a Paragonimus skin test. Only 4 schoolchildren out of 128 skin test-positive cases had Paragonimus sp. eggs in their sputum, all of which was collected on 1 day. Several types of crabs, which were identified as the second intermediate host of the Paragonimus species, were collected from markets and streams in a paragonimiasis endemic area for the inspection of metacercariae. Among the examined crabs, only "rock crabs" (Indochinamon ou) harbored Paragonimus sp. metacercariae, and it is speculated that the life cycle of Paragonimus sp. was maintained via rock crabs in Namback District, Lao PDR.     

Intestinal Paragonimiasis with Colonic Ulcer and Hematochezia in An Elderly Taiwanese Woman

A 94-year-old female with end-stage renal disease presents with fever, fatigue, and hematochezia. She had previously resided in Hunan Province, China, and Myanmar, and she immigrated to Taiwan 30 years ago. Colonoscopy revealed a colonic ulcer. Biopsy of the colonic ulcer showed ulceration of the colonic mucosa, and many Paragonimus westermani-like eggs were noted. Serum IgG antibody levels showed strong reactivity with P. westermani excretory-secretory antigens by ELISA. Intestinal paragonimiasis was thus diagnosed according to the morphology of the eggs and serologic finding. After treatment with praziquantel, hematochezia resolved. The present case illustrates the extreme manifestations encountered in severe intestinal paragonimiasis.     

A case of paragonimiasis in the abdominal subcutaneous tissue]

A 35-year-old housewife living in Seoul complained of a recurrent palpable abdominal mass. Excisional biopsy was done. The cystic mass showed an immature worm of Paragonimus sp. in the cyst cavity. It measured 7 x 4 mm and showed well-developed oral and ventral sucker, uterus, 5-branched ovary and intestine after acetocarmine staining. But the testes and vitelline duct were not developed fully and there was no egg in the uterus. The patient has eaten raw fish. The case of ectopic paragonimiasis in the abdominal subcutaneous tissue was presented.     

Paragonimiasis in the Abdominal Cavity and Subcutaneous Tissue: Report of 3 Cases

Paragonimiasis is a parasitic disease caused by the lung fluke, Paragonimus spp. Lung flukes may be found in various organs, such as the brain, peritoneum, subcutaneous tissues, and retroperitoneum, other than the lungs. Abdominal paragonimiasis raises a considerable diagnostic challenge to clinicians, because it is uncommon and may be confused with other abdominopelvic inflammatory diseases, particularly peritoneal tuberculosis, and peritoneal carcinomatosis. Also, subcutaneous paragonimiasis does not easily bring up clinical suspicion, due to its rarity. We herein report 2 cases of abdominal paragonimiasis and 1 case of subcutaneous paragonimiasis in Korea.     

Persisting antibody reaction in paragonimiasis after praziquantel treatment is elicited mainly by egg antigens

Antibody responses in serum and cerebrospinal fluid (CSF) samples from patients with active and chronic paragonimiasis and in sera from patients on whom follow-up studies were done after praziquantel treatment were analyzed using antigens of Paragonimus westermani prepared from eggs, metacercariae, juveniles of 4- and 7-week old, adult worms and recombinant protein of 28 kDa cruzipain-like cysteine protease (rPw28CCP). The patient sera/CSFs of active and chronic paragonimiasis revealed strong antibody reactions against the crude extracts of 4- and 7-week old juveniles as well as against those from egg and adult. rPw28CCP also showed specific reaction to the sera with active paragonimiasis. After the treatment, levels of specific antibodies in the sera gradually decreased to negative range in most patients. In some cases with persisting high antibody levels, however, the reactions at 27 kDa egg protein were sustained throughout the observation period of 34 months. The reactions at 35 and 32 kDa in adult extract and rPw28CCP disappeared rapidly after the treatment. Persistent antibody reactions even after successful treatment are provoked by continuous antigenic challenge from eggs which were not resolved by treatment.     

Current status of Paragonimus and paragonimiasis in Ecuador

A review of national and international publications on paragonimiasis in Ecuador, epidemiological records from the Ministry of Public Health and unpublished research data was conducted to summarise the current status of the parasite/disease. The purpose of the review is to educate physicians, policy-makers and health providers on the status of the disease and to stimulate scientific investigators to conduct further research. Paragonimiasis was first diagnosed in Ecuador 94 years ago and it is endemic to both tropical and subtropical regions in 19 of 24 provinces in the Pacific Coast and Amazon regions. Paragonimus mexicanus is the only known species in the country, with the mollusc Aroapyrgus colombiensis and the crabs Moreirocarcinus emarginatus, Hypolobocera chilensis and Hypolobocera aequatorialis being the primary and secondary intermediate hosts, respectively. Recent studies found P. mexicanus metacercariae in Trichodactylus faxoni crabs of the northern Amazon. Chronic pulmonary paragonimiasis is commonly misdiagnosed and treated as tuberculosis and although studies have demonstrated the efficacy of praziquantel and triclabendazole for the treatment of human infections, neither drug is available in Ecuador. Official data recorded from 1978-2007 indicate an annual incidence of 85.5 cases throughout the 19 provinces, with an estimated 17.2% of the population at risk of infection. There are no current data on the incidence/prevalence of infection, nor is there a national control programme.     

Evaluation of IgG4 Subclass Antibody Detection by Peptide-Based ELISA for the Diagnosis of Human Paragonimiasis Heterotrema

A synthetic peptide was prepared based on the antigenic region of Paragonimus westermani pre-procathepsin L, and its applicability for immunodiagnosis for human paragonimiasis (due to Paragonimus heterotremus) was tested using an ELISA to detect IgG4 antibodies in the sera of patients. Sera from other helminthiases, tuberculosis, and healthy volunteers were used as the references. This peptide-based assay system gave sensitivity, specificity, accuracy, and positive and negative predictive values of 100%, 94.6%, 96.2%, 100%, and 88.9%, respectively. Cross reactivity was frequently seen against the sera of fascioliasis (75%) and hookworm infections (50%). Since differential diagnosis between paragonimiasis and fascioliasis can be easily done by clinical presentation and fascioliasis serology, this cross reaction is not a serious problem. Sera from patients with other parasitoses (0-25%) rarely responded to this synthetic antigen. This synthetic peptide antigen seems to be useful for development of a standardized diagnostic system for paragonimiasis.     

Identification of the human paragonimiasis causative agent in Lao People's Democratic Republic

To assess the species of human paragonimiasis in Lao People's Democratic Republic, 6 ovum samples from 6 native confirmed paragonimiasis patients were examined with polymerase chain reaction (PCR) amplifying the internal transcribed spacer 2 (ITS2). The PCR products were sequenced, and a homology search was performed using the GenBank. All 6 sequences were identical with Paragonimus heterotremus ITS2. Our work suggests that P. heterotremus may be the main etiological agent of human paragonimiasis in this locality.     

Choriocarcinoma metastatic to the breast diagnosed by fine needle aspiration.

Fine needle aspiration (FNA) was used to study nodules in the left breast of a patient with a previous history of uterine choriocarcinoma. The FNA smears contained numerous malignant mononucleated cells and multinucleated giant cells. The cytologic diagnosis was metastatic choriocarcinoma, which was confirmed by histologic study of excised tissue. That diagnosis would have been difficult to make cytologically if the previous history had not been known; the differential diagnosis of multinucleated giant cells in an aspirate from a breast mass is discussed.     

Rapid Identification of Paragonimiasis Foci by Lay Informants in Lao People's Democratic Republic

Background

Paragonimiasis is a food-borne trematodiasis leading to lung disease. Worldwide, an estimated 21 million people are infected. Foci of ongoing transmission remain often unnoticed. We evaluated a simple questionnaire approach using lay-informants at the village level to identify paragonimiasis foci and suspected paragonimiasis cases.

Methodology/Principal Findings

The study was carried out in an endemic area of Lao People''s Democratic Republic. Leaders of 49 remote villages in northern Vientiane Province were asked to notify suspected paragonimiasis patients using a four-item questionnaire sent through administrative channels: persons responding positively for having chronic cough (more than 3 weeks) and/or blood in sputum with or without fever. We validated the village leaders'' reports in ten representative villages with a door-to-door survey. We examined three sputa of suspected patients for the presence of Paragonimus eggs and acid fast bacilli. 91.8% of village leaders participated and notified a total of 220 suspected patients; 76.2% were eventually confirmed; an additional 138 suspected cases were found in the survey. Sensitivity of village leaders'' notice for “chronic cough” and “blood in sputum” was 100%; “blood in sputum” alone reached a sensitivity of 85.7%.

Significance

Our approach led to the identification of three previously unknown foci of transmission. A rapid and simple lay-informant questionnaire approach is a promising low-cost community diagnostic tool of paragonimiasis control programs.     

Three Cases of Paragonimiasis in a Family

Paragonimiasis typically results from the consumption of raw or improperly cooked crustacea, especially crabs and crayfish. Although previously endemic in Korea, the prevalence of this disease decreased in the early 1970s because of educational campaigns and fewer intermediate hosts as a result of ecological changes. Recently, we were presented with a family where all members were infected with Paragonimus after ingestion of Kejang (= drunken crab). The mother was hospitalized for general myalgia and weakness first, followed by the father, who was hospitalized for dyspnea 2 month later. After the parents were diagnosed with paragonimiasis, we recommended their daughter to visit our hospital for a checkup, because they all had eaten freshwater crabs soaked in soybean sauce. She complained of generalized myalgia, fever, and pleuritic pain, and was also diagnosed with paragonimiasis. Peripheral blood of the 3 patients revealed hypereosinophilia, and computed tomography (CT) scans of their chests showed pleural effusion. The results of antibody tests by ELISA were positive for paragonimiasis. We report here the case series of familial paragonimiasis in a modern urban city, rather than in a typical endemic area.     

Pulmonary paragonimiasis. Report of a case with diagnosis by fine needle aspiration cytology.

We report a case of paragonimiasis in a Nigerian woman evaluated for symptoms of chronic respiratory disease five years after chemotherapy for primary lymphoma of the breast. Fine needle aspiration of one of two fibrocavitary pulmonary lesions yielded thick, brown material in which ova diagnostic of Paragonimus westermani were identified cytologically. This disease is unusual in natives of North America but is seen in travelers and immigrants from Asia, Africa, and South and Central America, where it is endemic. The infection can be fatal, especially if it involves the central nervous system. The clinical differential is broad, but an accurate diagnosis may be made by fine needle aspiration, thus allowing proper treatment.     

Breast metastasis from uterine leiomyosarcoma diagnosed by fine needle aspiration: a case report

BACKGROUND: Leiomyosarcomas of the breast are a rare subgroup of primary breast sarcomas. Even more rare is breast metastasis of an extramammary leiomyosarcoma. To date, only 4 cases have been reported in the literature. CASE: We report a case of breast metastatic leiomyosarcoma in a 58-year-old woman with a prior history of uterine leiomyosarcoma, resected 18 months earlier. The breast mass was palpable and a fine needle aspiration (FNA) was performed. The microscopic examination showed cellular smears composed of loosely structured clusters and tissue fragments of spindle-shaped and polygonal or rounded malignant cells in disorderly arrangement. The tumor cells were medium- or large-sized, with basophilic cytoplasm and enlarged, irregular, hyperchromatic nuclei with nucleoli. Tumor giant cells and multinucleation were also present. The morphologic features along with immunocytochemical positivity for desmin, muscle-specific actin and vimentin indicated the diagnosis of a metastatic leiomyosarcoma. CONCLUSION: FNA cytology can be a reliable method for the diagnosis of leiomyosarcoma. The morphologic criteria in combination Swith the clinical history and the immunocytochemical findings can indicate a definitive diagnosis and avoid additional painful and time-consuming diagnostic procedures for the appropriate patient's further clinical management.     

A pulmonary paragonimiasis case mimicking metastatic pulmonary tumor

Pulmonary paragonimiasis is a relatively rare cause of lung disease revealing a wide variety of radiologic findings, such as air-space consolidation, nodules, and cysts. We describe here a case of pulmonary paragonimiasis in a 27-year-old woman who presented with a 2-month history of cough and sputum. Based on chest computed tomography (CT) scans and fluorodeoxyglucose positron emission tomography (FDG-PET) findings, the patient was suspected to have a metastatic lung tumor. However, she was diagnosed as having Paragonimus westermani infection by an immunoserological examination using ELISA. Follow-up chest X-ray and CT scans after chemotherapy with praziquantel showed an obvious improvement. There have been several reported cases of pulmonary paragonimiasis mimicking lung tumors on FDG-PET. However, all of them were suspected as primary lung tumors. To our knowledge, this patient represents the first case of paragonimiasis mimicking metastatic lung disease on FDG-PET CT imaging.     

Paragonimiasis: an important food-borne zoonosis in China

The lung fluke, Paragonimus westermani, is of major socioeconomic importance in Asia. The parasite is transmitted via snails to freshwater crabs or crayfish, then to humans and other mammals, such as cats and dogs, and causes paragonimiasis. This review provides a background on the parasite and its life cycle; summarizes key aspects regarding the pathogenesis, diagnosis and treatment of paragonimiasis; describes the geographic distribution and prevalence of paragonimiasis; and makes some recommendations for future research and the control of this important disease in China.