ABSTRACT
Hymenolepis diminuta is a common parasite of rats and mice, but is very rare in humans with cases reported from various parts of the world. Here, we reported a case of Hymenolepis diminuta infection involving both the respiratory and digestive tracts in a 49-year-old male patient whose initial imaging and symptoms were strikingly similar to pneumonia. Since no disease-causing pathogens were found during routine examinations, we considered respiratory infection by specific pathogens before metagenomic next-generation sequencing of broncho-alveolar lavage fluid confirmed the diagnosis of Hymenolepis diminuta. After confirming the diagnosis, we retested the patient's stool repeatedly and found Hymenolepis diminuta eggs finally. To help doctors better understand this condition and avoid misdiagnosis, this article provided a summary of the clinical characteristics, diagnostic techniques, and therapeutic options for infection by Hymenolepis diminuta.
Subject(s)
Hymenolepiasis , Hymenolepis diminuta , Male , Middle Aged , Hymenolepiasis/diagnosis , Hymenolepiasis/drug therapy , Humans , Animals , Feces/parasitology , Lung Diseases, Parasitic/diagnosis , Lung Diseases, Parasitic/drug therapy , Lung Diseases, Parasitic/parasitologyABSTRACT
In this case report, we address the diagnostic challenges and clinical implications of severe infection with Lophomonas blattarum in a patient initially suspected of experiencing long COVID symptoms. We describe the patient's medical history, initial symptoms, diagnostic tests, and treatment. A female patient with diabetes in her early 60s presented with severe shortness of breath and was initially diagnosed with diabetic ketoacidosis (DKA). After resolution of her DKA symptoms, persistent respiratory issues led to a COVID-19 test, which was negative. A chest computed tomography scan revealed abnormalities, prompting bronchoscopy and bronchoalveolar lavage fluid analysis, which confirmed the presence of L. blattarum. Notably, the protozoan remained mobile and viable even after a 4-day transport at ambient temperature. This case emphasizes the importance of considering alternative diagnoses and improving awareness about L. blattarum infection in patients with respiratory symptoms, for timely and accurate management.
Subject(s)
COVID-19 , Diabetes Mellitus , Diabetic Ketoacidosis , Lung Diseases, Parasitic , Protozoan Infections , Humans , Female , Protozoan Infections/complications , Protozoan Infections/diagnosis , Lung Diseases, Parasitic/diagnosis , Lung Diseases, Parasitic/drug therapy , Lung Diseases, Parasitic/etiology , Iran , Post-Acute COVID-19 Syndrome , COVID-19/complications , Diabetic Ketoacidosis/complicationsABSTRACT
BACKGROUND: Paragonimiasis is a parasitic disease primarily contracted through consumption of undercooked freshwater crustaceans or wild boar meat. Large-scale nationwide epidemiological data on paragonimiasis are lacking. In this study, we aimed to investigate the nationwide epidemiology of hospitalized patients with paragonimiasis in Japan using a comprehensive nationwide Japanese administrative database. METHODS: We evaluated the Japanese Diagnosis Procedure Combination (DPC) data of patients diagnosed with pulmonary paragonimiasis between April 1, 2012 and March 30, 2020. The patients' address and information, including age, sex, treatment (medication: praziquantel; surgery: open thoracotomy or intracranial mass extirpation), Japan coma scale, comorbidities, and length of hospital stay, were extracted. RESULTS: Of the 49.6 million hospitalized patients, data were extracted on 73 patients with paragonimiasis, of whom 36 were male and 37 were female. The mean age was 49.7 years and the mean length of stay was 12.5 days. The most frequent comorbidity was pleural effusion (31.5 %), followed by pneumothorax (13.7 %). The sites of ectopic paragonimiasis in organs other than the lung included the liver (5.5 %), skin (4.1 %), and brain (2.7 %). Geographically, most patients were from the Kyushu region (54.8 %), followed by the Kanto region (22.0 %). Fukuoka Prefecture had the highest number of patients (22.0 %) by prefecture. During the study period, an average of 9.1 patients/year were hospitalized with lung paragonimiasis in Japan. CONCLUSION: Paragonimiasis has not completely disappeared in Japan; thus, physicians should be aware of paragonimiasis in the Kyushu region, especially in the Fukuoka Prefecture.
Subject(s)
Databases, Factual , Paragonimiasis , Humans , Paragonimiasis/epidemiology , Japan/epidemiology , Male , Female , Middle Aged , Adult , Aged , Length of Stay/statistics & numerical data , Lung Diseases, Parasitic/epidemiology , Lung Diseases, Parasitic/parasitology , Lung Diseases, Parasitic/drug therapy , Young Adult , Hospitalization/statistics & numerical data , Praziquantel/therapeutic use , Adolescent , Animals , Comorbidity , East Asian PeopleABSTRACT
Parasitic lung diseases are caused by a number of parasites as a result of transient passage in the lung or as a result of an immunologic reaction. The clinical presentation may be in the form of focal or cystic lesions, pleural effusion or diffuse pulmonary infiltrates. With increasing globalisation, it is important to consider parasitic infections in the differential diagnosis of lung diseases. This is particularly important since early identification and prompt therapy result in full cure of these conditions. In this review, we summarise the most common parasitic lung diseases.
Subject(s)
Lung Diseases, Parasitic , Pleural Effusion , Humans , Lung Diseases, Parasitic/diagnosis , Lung Diseases, Parasitic/drug therapy , Diagnosis, Differential , ThoraxABSTRACT
Diagnosis of pediatric paragonimiasis is difficult because of its non-specific clinical manifestations. We retrospectively reviewed the records of pediatric paragonimiasis in Children's Hospital of Fudan University from January 2011 to May 2019. The confirmed diagnosis of paragonimiasis was based on positive anti-parasite serological tests from the local Center for Disease Control (CDC). A total of 11 patients (mean age: 7.7 ± 3.1, male-female ratio: 7:4) diagnosed as paragonimiasis were included. 81.8% were from endemic areas such as Sichuan and Yunnan, and 36% had a clear history of raw crab or crayfish consumption. The characteristic clinical features of pediatric paragonimiasis were eosinophilia (100%), pleural effusion (81.8%), hepatomegaly (54.5%), ascites (54.5%), and subcutaneous nodules (45.5%). Misdiagnosed with other diseases including tuberculosis (18.2%), pneumonia (9.1%), intracranial space-occupying lesions (9.1%) and brain abcess (9.1%) led to rehospitalization and prolonged hospitalization. For treatment, a 3-day course of 150 mg/kg praziquantel (PZQ) didn't show ideal treatment effectivity and 63.6% needed more than one course of PZQ, while triclabendazole in a total dose of 10 mg/kg had a better efficacy to stubborn manifestations. This study indicated that pediatric paragonimiasis was often misdiagnosed, and the treatment with a 3-day course of 150 mg/kg PZQ had a high rate of failure.
Subject(s)
Lung Diseases, Parasitic/diagnosis , Lung Diseases, Parasitic/epidemiology , Paragonimiasis/diagnosis , Paragonimiasis/epidemiology , Animals , Anthelmintics/therapeutic use , Child , Child Health , China/epidemiology , Diagnosis, Differential , Diagnostic Errors , Female , Hospitals , Humans , Lung Diseases, Parasitic/drug therapy , Lung Diseases, Parasitic/parasitology , Male , Paragonimiasis/drug therapy , Paragonimiasis/parasitology , Paragonimus/pathogenicity , Pleural Effusion , Praziquantel/therapeutic use , Retrospective Studies , Risk FactorsABSTRACT
Parasites can cause respiratory symptoms through focal or diffuse lung involvement, depending on the location of the parasite and the host's immune response. Pulmonary involvement can be a major feature of some parasitic infections or a complication during transpulmonary larval migration. Parasites should be included in the differential diagnosis of common lung diseases, especially in the presence of peripheral eosinophilia or extrapulmonary symptoms (abdominal pain, diarrhea, jaundice, skin lesions).
Subject(s)
Anthelmintics/therapeutic use , Antiprotozoal Agents/therapeutic use , Lung Diseases, Parasitic/diagnosis , Lung Diseases, Parasitic/drug therapy , Animals , Child , HumansABSTRACT
An orphaned black bear (Ursus americanus) cub, estimated to be 9 months-of-age was presented to a wildlife rehabilitation facility in December of 2016. The cub was afebrile, under-weight (6.8 kg) and had a cough condition. Centrifugal sugar fecal flotation examination failed to detect any gastrointestinal helminth or protozoan parasites, but revealed the presence of first-stage nematode larvae (L1). Large numbers of L1 (>8000 L1/g) identified as Crenosoma sp. based on morphology were recovered using the Baermann technique. Three species (Crenosoma petrowi, Crenosoma potos, Crenosoma vulpis) have been reported from black bears. Based on larval length measurements (range = 253-277 µm; mean = 263 µm; n = 8), the L1 were tentatively identified as C. petrowi. Further molecular characterization using Polymerase Chain Reaction (PCR) and DNA sequencing of the small subunit (SSU) RNA gene and two regions of the large subunit (LSU) rRNA gene did not match any submissions in GenBank, but were most similar to Crenosoma mephiditis. There is a paucity of molecular data for members of the genus Crenosoma, with only information for Crenosoma vulpis (red fox), C. mephitidis (skunks), Crenosoma striatum (hedgehog) and Crenosoma sp. (red panda) in GenBank. Molecular analysis eliminates C. vulpis as a possibility in this case but due to the lack of submissions in GenBank, the identification of the L1 as C. petrowi based on length measurements could not be confirmed. Receiving in total, three separate courses of treatment with fenbendazole (50 mg/kg, oral, once a day for 3 days), fecal larval shedding ceased and clinical signs resolved. The black bear cub was released into the wild in June 2017. This is the first report of clinical chronic respiratory disease due to Crenosoma sp. infection in a black bear.
Subject(s)
Antinematodal Agents/therapeutic use , Fenbendazole/therapeutic use , Lung Diseases, Parasitic/veterinary , Metastrongyloidea/isolation & purification , Strongylida Infections/veterinary , Ursidae , Animals , Female , Lung Diseases, Parasitic/diagnosis , Lung Diseases, Parasitic/drug therapy , Lung Diseases, Parasitic/parasitology , Metastrongyloidea/classification , New Brunswick , Strongylida Infections/diagnosis , Strongylida Infections/drug therapy , Strongylida Infections/parasitologyABSTRACT
Paragonimiasis is a parasite infection caused by several species of Paragonimus, a trematode that is transmitted through the consumption of raw or undercooked crabs and that has been found in the subtropical areas of America, Asia and Africa. This infection mainly affects the lungs, causing clinical and radiological manifestations very similar to pulmonary tuberculosis, so it should always be included in the differential diagnosis. We present the case of a 7-year-old school patient, hospitalized with the diagnosis of pulmonary paragonimiasis, who had a favorable evolution after receiving treatment with triclabendazole.
La paragonimiasis es una parasitosis provocada por varias especies de Paragonimus, un trematodo que se transmite a través del consumo de cangrejos poco cocidos o crudos y que se ha encontrado en áreas tropicales y subtropicales de América, Asia y África. Esta infección afecta, principalmente, los pulmones y provoca manifestaciones clínicas y radiológicas muy similares a la tuberculosis pulmonar, por lo cual siempre debe incluirse dentro del diagnóstico diferencial. Se presenta el caso de una niña escolar de 7 años de edad, hospitalizada con el diagnóstico de paragonimiasis pulmonar, quien presentó evolución favorable luego de recibir tratamiento con triclabendazol.
Subject(s)
Lung Diseases, Parasitic/diagnosis , Paragonimiasis/diagnosis , Triclabendazole/administration & dosage , Animals , Antiplatyhelmintic Agents/administration & dosage , Child , Female , Humans , Lung Diseases, Parasitic/drug therapy , Lung Diseases, Parasitic/parasitology , Paragonimiasis/drug therapy , Paragonimus/isolation & purificationSubject(s)
Asthma/parasitology , Lung Diseases, Parasitic/diagnosis , Strongyloidiasis/diagnosis , Aged , Asthma/diagnosis , Asthma/drug therapy , Diagnosis, Differential , Female , Humans , Lung Diseases, Parasitic/drug therapy , Parasite Egg Count , Strongyloidiasis/drug therapy , Thiabendazole/therapeutic useABSTRACT
The genus Acanthamoeba, which may cause different infections in humans, occurs widely in the environment. Lung inflammation caused by these parasites induces pulmonary pathological changes such as pulmonary necrosis, peribronchial plasma cell infiltration, moderate desquamation of alveolar cells and partial destruction of bronchial epithelial cells, and presence of numerous trophozoites and cysts among inflammatory cells. The aim of this study was to assess the influence of plant extracts from Artemisia annua L. on expression of the toll-like receptors TLR2 and TLR4 in lungs of mice with acanthamoebiasis. A. annua, which belongs to the family Asteraceae, is an annual plant that grows wild in Asia. In this study, statistically significant changes of expression of TLR2 and TLR4 were demonstrated. In the lungs of infected mice after application of extract from A. annua the expression of TLRs was observed mainly in bronchial epithelial cells, pneumocytes (to a lesser extent during the outbreak of infection), and in the course of high general TLR expression. TLR4 in particular was also visible in stromal cells of lung parenchyma. In conclusion, we confirmed that a plant extract of A. annua has a modulatory effect on components of the immune system such as TLR2 and TLR4.
Subject(s)
Acanthamoeba/physiology , Amebiasis/drug therapy , Artemisia annua/chemistry , Lung Diseases, Parasitic/drug therapy , Plant Extracts/therapeutic use , Toll-Like Receptors/metabolism , Amebiasis/metabolism , Animals , DNA, Complementary/metabolism , Immunohistochemistry , Lung/parasitology , Lung/pathology , Lung Diseases, Parasitic/metabolism , Mice , Mice, Inbred BALB C , Plant Extracts/pharmacology , RNA, Messenger/metabolism , RNA, Protozoan/genetics , RNA, Protozoan/isolation & purification , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Reverse Transcription , Toll-Like Receptor 2/drug effects , Toll-Like Receptor 2/genetics , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/drug effects , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism , Toll-Like Receptors/drug effects , Toll-Like Receptors/geneticsABSTRACT
A 43-year-old woman was referred to our hospital with peripheral blood hypereosinophilia and abnormal chest X-ray findings. Her pleural effusion revealed hypereosinophilia and a low glucose level. She was diagnosed with pulmonary paragonimiasis based on an elevated antibody level of Paragonimiasis westermani. Although she had no medical history of allergic disorders, a pulmonary function test revealed bronchodilator reversibility. After praziquantel therapy, her symptoms, hypereosinophilia in peripheral blood, and pleural effusion were improved. A repeated pulmonary function test after praziquantel therapy showed a negative bronchodilator response. Pulmonary paragonimiasis may induce bronchodilator reversibility during the acute phase of infection.
Subject(s)
Bronchi/physiopathology , Lung Diseases, Parasitic/complications , Lung Diseases, Parasitic/physiopathology , Paragonimiasis/complications , Paragonimiasis/physiopathology , Respiratory Function Tests/methods , Acute Disease , Adult , Anthelmintics/therapeutic use , Bronchodilator Agents/administration & dosage , Eosinophilia/diagnostic imaging , Eosinophilia/etiology , Female , Humans , Lung Diseases, Parasitic/diagnosis , Lung Diseases, Parasitic/drug therapy , Paragonimiasis/diagnosis , Paragonimiasis/drug therapy , Pleural Effusion/diagnostic imaging , Pleural Effusion/etiology , Praziquantel/therapeutic use , Radiography, ThoracicABSTRACT
Protozoic infections are prevalent worldwide, particularly in immunosuppressed patients. We reported the case of a patient from the city of Viña del Mar, Chile, a carrier of acute myeloid leukemia in whom an infection by Lophomonas sp. was confirmed by bronchoalveolar lavage. She was treated with antibiotics but died of complications of the underlying disease. There is little literature available on this microorganism. We conclude that Lophomonas sp. should be considered as a diagnostic possibility if protozoa are found in bronchoalveolar lavage of immunosuppressed patients.
Las infecciones por protozoos son prevalentes a nivel mundial, en particular en pacientes inmunosuprimidos. Comunicamos el caso de una paciente procedente de la ciudad de Viña del Mar, Chile, portadora de leucemia mieloide aguda en quiense confirmó una infección por Lophomonas sp. en lavado bronquioalveolar. Se manejó con antibióticos, pero falleció decomplicaciones de su enfermedad de base. Existe poca literatura disponible respecto a este microorganismo. Concluimos que debe considerarse a Lophomonas sp. como posibilidad diagnóstica si se encuentran protozoos en lavados bronquioalveolares de pacientes inmunosuprimidos.
Subject(s)
Lung Diseases, Parasitic , Parabasalidea , Protozoan Infections , Aged , Fatal Outcome , Female , Humans , Leukemia, Myeloid, Acute/complications , Lung Diseases, Parasitic/complications , Lung Diseases, Parasitic/diagnosis , Lung Diseases, Parasitic/drug therapy , Protozoan Infections/complications , Protozoan Infections/diagnosis , Protozoan Infections/drug therapyABSTRACT
We report a case of chronic Schistosoma haematobium infection with pseudometastatic pulmonary nodules and high-grade squamous cell carcinoma in a 30-year-old man in Mali. Lung biopsies revealed chronic pulmonary involvement of S. haematobium and ruled out lung metastases.
Subject(s)
Carcinoma, Squamous Cell/complications , Lung Diseases, Parasitic/diagnosis , Lung Diseases, Parasitic/parasitology , Schistosomiasis/complications , Schistosomiasis/parasitology , Urinary Bladder Neoplasms/complications , Adult , Animals , Anthelmintics/therapeutic use , Biopsy , Carcinoma, Squamous Cell/diagnosis , Chronic Disease , Humans , Lung Diseases, Parasitic/drug therapy , Male , Praziquantel/therapeutic use , Schistosoma haematobium/chemistry , Tomography, X-Ray Computed , Urinary Bladder Neoplasms/diagnosisABSTRACT
RESUMEN Las infecciones por protozoos son prevalentes a nivel mundial, en particular en pacientes inmunosuprimidos. Comunicamos el caso de una paciente procedente de la ciudad de Viña del Mar, Chile, portadora de leucemia mieloide aguda en quiense confirmó una infección por Lophomonas sp. en lavado bronquioalveolar. Se manejó con antibióticos, pero falleció decomplicaciones de su enfermedad de base. Existe poca literatura disponible respecto a este microorganismo. Concluimos que debe considerarse a Lophomonas sp. como posibilidad diagnóstica si se encuentran protozoos en lavados bronquioalveolares de pacientes inmunosuprimidos.
ABSTRACT Protozoic infections are prevalent worldwide, particularly in immunosuppressed patients. We reported the case of a patient from the city of Viña del Mar, Chile, a carrier of acute myeloid leukemia in whom an infection by Lophomonas sp. was confirmed by bronchoalveolar lavage. She was treated with antibiotics but died of complications of the underlying disease. There is little literature available on this microorganism. We conclude that Lophomonas sp. should be considered as a diagnostic possibility if protozoa are found in bronchoalveolar lavage of immunosuppressed patients.
Subject(s)
Aged , Female , Humans , Protozoan Infections , Parabasalidea , Lung Diseases, Parasitic , Protozoan Infections/complications , Protozoan Infections/diagnosis , Protozoan Infections/drug therapy , Leukemia, Myeloid, Acute/complications , Fatal Outcome , Lung Diseases, Parasitic/complications , Lung Diseases, Parasitic/diagnosis , Lung Diseases, Parasitic/drug therapyABSTRACT
BACKGROUND: Primary pulmonary amoeba is very rare and here we report a case of a 68-year-old man presenting with primary pulmonary amoeba after undergoing chemotherapy for lung adenocarcinoma. CASE PRESENTATION: In October 2016, the man aged 68 was admitted to our hospital because of repeated cough for 8 months and hemoptysis for 1 month. He was diagnosed lung adenocarcinoma and underwent surgery in 2012 without receiving chemotherapy. In March 2016, the patients suffered recurrence of cancer and was treated with chemotherapy. After 2 months of chemotherapy, the patient had consistent cough with white sputum, and chest CT showed a local lung nodule. The physicians suspected that the patient had pulmonary infectious diseases, and he was treated with empirical antibacterial treatment. However, his symptom wasn't relieved and later the percutaneous lung biopsy found trophozites of Entamoeba histolytica. After administration of metronidazole, the symptoms of the patient were markedly relieved and the lesions were absorbed. CONCLUSIONS: In such cases where patients with pulmonary nodules were in immunodeficiency state and had adequate but ineffective anti-bacterial treatment, Entamoeba histolytica infection could be one of the rare causes. Percutaneous lung biopsy should be recommended and specific dying for parasites should be done when necessary.
Subject(s)
Amebiasis/diagnosis , Antiprotozoal Agents/therapeutic use , Entamoeba histolytica/isolation & purification , Lung Diseases, Parasitic/diagnosis , Metronidazole/therapeutic use , Adenocarcinoma/drug therapy , Adenocarcinoma/surgery , Adenocarcinoma of Lung , Aged , Amebiasis/drug therapy , Amebiasis/parasitology , Antineoplastic Agents/therapeutic use , China , Humans , Lung Diseases, Parasitic/drug therapy , Lung Diseases, Parasitic/parasitology , Lung Neoplasms/drug therapy , Lung Neoplasms/surgery , MaleABSTRACT
CASE PRESENTATION: A man in his 20s presented with 2 months of mild fatigue and intermittent hemoptysis of less than a tablespoon per episode. He was previously healthy and was on no medications. He denied fevers, night sweats, weight loss, wheezing, dyspnea, musculoskeletal symptoms, and rashes. He had emigrated from a South American country to the United States 3 years earlier. He worked as a groundskeeper but had no exposures to animals, mold, or dusts. He reported rare prior cigarette smoking with no history of alcohol or drug use. He was unsure whether he had received the Bacillus Calmette-Guérin vaccine.
Subject(s)
Lung Diseases, Parasitic/diagnosis , Paragonimiasis/diagnosis , Adult , Antinematodal Agents/therapeutic use , Diagnosis, Differential , Dyspnea/parasitology , Hemoptysis/parasitology , Humans , Lung Diseases, Parasitic/drug therapy , Male , Paragonimiasis/drug therapy , Praziquantel/therapeutic use , Tomography, X-Ray Computed , Tuberculosis, Pulmonary/diagnosisABSTRACT
The present study investigated for the first time the occurrence of pulmonary and intestinal parasites of cats in Cyprus. Cats from five districts of Cyprus (Lefkosia, Lemesos, Larnaka, Pafos and Ammochostos) were examined by classical parasitological methods and the identity of lungworm larvae, whenever present, was confirmed by PCR-coupled sequencing. A total of 185 cats, 48 living exclusively indoors and 137 with outdoor access, were included in the study. Parasites were found in 66 (35.7%) of the examined cats, i.e. Toxocara cati (12%), Cystoisospora rivolta (12%), Joyeuxiella/Diplopylidium spp. (7%), Giardia spp. (6.5%), Troglostrongylus brevior (5%), Cystoisospora felis (2.5%), Aelurostrongylus abstrusus (2%), Taenia spp. (0.5%) and Dipylidium caninum (0.5%). Mixed infections were recorded in 18 cats. Cats that lived exclusively indoors or had received an antiparasitic treatment in the last 6 months were less likely to be infected (p < 0.05). Moreover, cats younger than 1 year old were more likely to shed first-stage larvae of T. brevior (p = 0.04). The present study shows that cats in Cyprus are infected at a high percentage by a variety of parasites that potentially affect their health and also, in some cases (i.e. T. cati, D. caninum, Giardia spp.), may have an impact on human health. Moreover, it was revealed that T. brevior, a lungworm of emerging significance, is present on the island, rendering Cyprus the easternmost distribution border of this parasite in Europe to date.
Subject(s)
Cat Diseases/epidemiology , Intestinal Diseases, Parasitic/epidemiology , Intestinal Diseases, Parasitic/veterinary , Lung Diseases, Parasitic/epidemiology , Lung Diseases, Parasitic/veterinary , Strongylida Infections/epidemiology , Animals , Antiparasitic Agents/therapeutic use , Cat Diseases/drug therapy , Cat Diseases/parasitology , Cats , Coinfection/parasitology , Cyprus/epidemiology , Feces/parasitology , Intestinal Diseases, Parasitic/drug therapy , Larva , Lung Diseases, Parasitic/drug therapy , Metastrongyloidea/genetics , Polymerase Chain Reaction , Strongylida Infections/parasitology , Strongylida Infections/veterinaryABSTRACT
BACKGROUND: The anthelmintic efficacy of the 0.5% w/v topical formulation of eprinomectin (EPN), EPRINEX® Pour-on (Merial) when administered at 1 mg/kg body weight was evaluated in sheep in two dose confirmation laboratory studies and one multicenter field study. In addition, the pharmacokinetics of EPN when administered at that dosage to adult sheep was determined. RESULTS: In the two dose confirmation studies, which included 10 sheep each, sheep treated with topical EPN had significantly (p < 0.05) fewer of the following nematodes than the untreated sheep with overall reduction of nematode counts by >99%: adult Dictyocaulus filaria, Haemonchus contortus, Teladorsagia circumcincta(pinnata/trifurcata), Trichostrongylus axei, T. colubriformis, T. vitrinus, Cooperia curticei, Nematodirus battus, Strongyloides papillosus, Chabertia ovina and Oesophagostomum venulosum, and inhibited fourth-stage Teladorsagia larvae. A total of 196 sheep harboring naturally acquired gastrointestinal nematode infections were included in the field efficacy study at two sites each in Germany (48 Merino x Ile de France lambs, 52 adult Merino females) and in Italy (adult male and female Bagnolese, Lacaune, Lacaune x Bagnolese, Bagnolese x Sarda sheep; 48 animals per site). Animals were blocked on pre-treatment body weight and within each block, one animal was randomly assigned to the control (untreated) group and three animals were randomly assigned to be treated with topical EPN. Examination of feces 14 days after treatment demonstrated that, relative to the controls, topical EPN-treated sheep had significantly (p < 0.0001) lower strongylid egg counts. Reduction was ≥97% at each site and 98.6% across all sites. Pharmacokinetics of EPN following single treatment with topical EPN were determined in eight ~4.5 year old female Merino cross sheep based on the analysis of plasma samples which were collected from two hours to 21 days following treatment. The main pharmacokinetic parameters were: Cmax 6.20 ± 1.71 ng/mL, AUClast 48.8 ± 19.2 day*ng/mL, Tmax 3.13 ± 2.99 days and T1/2 6.40 ± 2.95 days. No treatment-related health problems or adverse drug events were observed in any study. CONCLUSION: These studies demonstrated 0.5% w/v EPN administered topically at 1 mg/kg body weight to be highly efficacious against a broad range of ovine gastrointestinal nematodes and D. filaria lungworms and well tolerated by sheep of different ages, breeds, gender and physiological status.