Occurrence of Hymenolepis diminuta: a potential helminth of zoonotic importance in murid rodents / Ocorrência de Hymenolepis diminuta: um helminto potencial de importância zoonótica em roedores murídeos

The study reveals the prevalence of a potential rodent-borne zoonotic helminth species, Hymenolepis diminuta in commensal rodents caught from irrigated and rain-fed areas of Swat, Pakistan. Three hundred and fifty rodents (269 rats and 81 mice) trapped during vegetative, flowering/fruiting and mature/harvesting stages of crops were studied from 2011-2013. Hymenolepisdiminuta eggs were identified on the basis of their shape, size, colour and markings on the surface of the egg shell and three pairs of embryonic hook-lets. Overall prevalence of H. diminuta was 3.14% (n=11/350). The highest prevalence 3.49% (n=5/143) of H. diminuta was noted at harvesting stages of the crops whereas the lowest 2.59% (n=2/77) during vegetative stage. Infection was higher in males 3.25% (n=7/215) than females 2.96% (n=4/135). Adult rodents were highly infected while no sub-adult was found infected. Infection was higher in mice 3.70% (3/81) than rats 2.69% (8/269) while no significance (p=1.0000:0.1250 to 32.00 CI). Rats and mice appears to show the most suitable reservoirs by hosting H. diminuta a zoonotic helminth. The presence of these rodents in all possible habitats can act as a main channel of transferring parasites through various habitats and can pose a hazard to humans in the area.

O estudo revela a prevalência de uma espécie potencial de helmintos zoonóticos transmitidos por roedores, Hymenolepis diminuta, em roedores comensais capturados em áreas irrigadas e alimentadas pela chuva de Swat, Paquistão. Trezentos e cinquenta roedores (269 ratos e 81 camundongos) presos durante os estágios vegetativo, floração/frutificação e maturidade/colheita das safras foram estudados de 2011-2013. Ovos de Hymenolepisdiminuta foram identificados com base em sua forma, tamanho, cor e marcações na superfície da casca do ovo e três pares de anzóis embrionários. A prevalência geral de H. diminuta foi de 3,14% (n = 11/350). A maior prevalência 3,49% (n = 5/143) de H. diminuta foi observada na fase de colheita das lavouras, enquanto a menor 2,59% (n = 2/77) durante a fase vegetativa. A infecção foi maior nos homens 3,25% (n = 7/215) do que nas mulheres 2,96% (n = 4/135). Roedores adultos foram altamente infectados, enquanto nenhum subadulto foi encontrado infectado. A infecção foi maior em camundongos 3,70% (3/81) do que em ratos 2,69% (8/269), embora sem significância (p = 1,0000: 0,1250 a 32,00 CI). Ratos e camundongos parecem mostrar os reservatórios mais adequados hospedando H. diminuta um helmintos zoonótico. A presença desses roedores em todos os habitats possíveis pode atuar como um canal principal de transferência de parasitas através de vários habitats e pode representar um perigo para os humanos na área.

Worldwide overview of human infections with Hymenolepis diminuta.

Hymenolepis diminuta is a zoonotic cestode parasitizing the small intestine of rodents (definitive hosts). Humans can accidentally enter into the life cycle of this tapeworm via the ingestion of infected insects (intermediate hosts) containing cestode cysticercoids in their body cavity. More than two centuries after the first record in humans, there are no accurate estimates of the number of human cases around the world. In order to have a more precise idea about the number of human cases with H. diminuta and the current status of the disease (hymenolepiasis) worldwide, we conducted a literature review of published records on human infection with H. diminuta. One thousand five hundred and sixty-one published records of infection with H. diminuta from 80 countries were identified. This review presents an estimate of the number of human cases with H. diminuta and a current overview of the prevalence, geographic distribution, symptoms, diagnosis, exposure to infective stages, and therapeutic approaches for this underestimated zoonotic tapeworm.

Coinfection with Hymenolepis nana, Hymenolepis diminuta, Giardia intestinalis, and Human Immunodeficiency Virus: A Case Report with Complex Immunologic Interactions.

AbstractWe describe the case of a 43-year-old human immunodeficiency virus-infected man receiving combined antiretroviral therapy and coinfected with Hymenolepis nana, Hymenolepis diminuta, and Giardia intestinalis, presenting as chronic diarrhea and critical weight loss. Immunological aspects of these interactions are reviewed.

Hymenolepis nana: A case report of a perfect IBD camouflage warrior.

RATIONALE: There is evidence that parasitic helminths can ameliorate colitis in animal models and humans. Although infections with Hymenolepis sp. are clinically benign, the immunomodulatory interactions between host and parasite are largely unknown. PATIENT CONCERNS: In this study we examined the intestinal mucosa of an adult asymptomatic patient harboring adult and larval dwarf tapeworms (Hymenolepis nana) who underwent surgery for an unrelated reason. INTERVENTIONS: Routine histology and immunohistochemistry were performed to characterize the host's response to the parasite. Parasitic DNA was sequenced to identify the tapeworm species. DIAGNOSES: Morphological and immunohistochemical studies showed a nearly complete absence of an anti-parasite host immune response. The outer surface of the parasite also showed prominent cross-reactivity with various tested leukocyte antigens. Our findings closely resemble experimentally obtained data from the H. diminuta-infected rat at the state of persistent colonization. OUTCOMES: Cross-reactivity of parasite-borne molecules with anti-human-leukocyte antibodies indicates a potential functional role in active modulation of the host's immune response. LESSIONS: We believe that better understanding of the host-cestode interaction will certainly extend our knowledge on auto-aggressive disorders such as inflammatory bowel disease and might provide potential treatment options.

[A rare case of Hymenolepis diminuta infection in a small child]. / Nadir bir olgu olarak küçük bir çocukta Hymenolepis diminuta enfeksiyonu.

Unlike Hymenolepis nana that transmits directly from person to person, the transmission of Hymenolepis diminuta to human is via accidentally ingesting of arthropods carrying cysticercoid larvae as intermediate host. In places with poor hygienic conditions, this cestod may cause seldom infections especially in children. Studies carried out on various populations have reported the prevalence rate of H.diminuta between 0.001% and 5.5%. Although the reported cases are mostly children, the disease can be seen in every age group. In this report, a pediatric case of H.diminuta infection is presented. A twenty one-month-old male patient with the symptoms of vomiting 3-4 times a day along with mud-like diarrhea continuing for a week was admitted to the pediatric outpatient clinic. According to the history, it was learned that the house where he lived was above a barn and there was a history of insect swallowing. Laboratory findings revealed iron-deficiency anemia. The macroscopic appearance of the stool was in a pale clay-like form, and by direct microscopic examination with lugol solution, 70-75 µm in diameter, thick-shelled and six central hookleted eggs that are characteristic for H.diminuta were identified. A six-day course of oral niclosamide was administered to the patient beginning with 500 mg on the first day and 250 mg on the following five days, together with the treatment for the iron deficiency anemia. After fifteen days, the oral niclosamide treatment was repeated. No H.diminuta eggs were detected in the parasitological examination performed one month after completion of the second round of treatment. This case has been presented to call attention to the importance of patient anamnesis and microscopic examination in the diagnosis of H.diminuta infection which is a rarely seen parasitosis.

Prevalence of ittestinal parasites among food handlers in western Iann / La prevalencia de parasitos intestinales entre los manipuladores de alimentos en el oeste de Iran

Parasitic infection is one of the problems that affect human health, especially in developing countries. In this study, all of the fast food shops, restaurants, and roast meat outlets of Khorramabad (Western Iran) and all the staff employed by them, some 210 people, were selected through a census and their stools were examined for the presence of parasites. The parasitological tests of direct wet-mount, Lugol's iodine staining, formaldehyde-ether sedimentation and Trichrome staining techniques were performed on the samples. The data was analyzed with a chi-square test and logistic regression was selected as the analytical model. The results showed 19 (9%) stool specimens were positive for different intestinal parasites. These intestinal parasites included Giardia lamblia 2.9%, Entamoeba coli 4.3%, Blastocystis sp. 1.4%, and Hymenolepis nana 0.5%. There was a significant difference between the presence of a valid health card, awareness of transmission of intestinal parasites, participation in training courses in environmental health with intestinal parasites (p < 0.05). No statistically significant difference was found between the rate of literacy and gender among patients infected with intestinal parasites (p > 0.05). To control parasitic infection in food handlers, several strategies are recommended such as stool examinations every three months, public education, application of health regulations, controlling the validity of health cards and training on parasitic infection transmission. In this regard, the findings of the present study can be used as a basis to develop preventive programs targeting food handlers because the spread of disease via them is a common problem worldwide.

Infección parasitaria es uno de los problemas de salud humana, especialmente en los países en desarrollo. En este estudio, todas las tiendas de comida rápida, restaurantes, y tiendas de carne asada en Khorramabad (oeste de Irán) y todo el personal que trabaja en ellos, incluyendo 210 personas fueron seleccionadas a través de los censos y las heces fueron examinadas para detectar la presencia de parásitos. La prueba parasitológica directa de mojado de montaje, la tinción de Lugol's yodo, sedimentación formaldehído-éter y tricrómicas técnicas de tinción se realizaron sobre las muestras. Los datos fueron analizados con la prueba de chi-cuadrado y regresión logística seleccionado como el modelo analítico. Los resultados mostraron 19 (9%) muestras de heces fueron positivos para diferentes parásitos intestinales. Los parásitos intestinales incluyen Giardia lamblia 2.9%, Entamoeba coli 4.3%, Blastocystis sp. 1.4%, Hymenolepis nana 0.5%. Hubo diferencia significativa entre la presencia de la tarjeta sanitaria válida, el conocimiento de la transmisión de los parásitos intestinales, la participación en cursos de formación en materia de salud ambiental con parásitos intestinales (p < 0.05). No hubo diferencia estadísticamente significativa entre la tasa de alfabetización y el sexo entre los pacientes infectados con parásitos intestinales (p > 0.05). Para controlar la infección parasitaria en los manipuladores de alimentos se recomiendan varias estrategias, tales como examen de heces cada tres meses, la educación pública, se aplican las normas sanitarias, el control de validez de la tarjeta sanitaria y la transmisión formación infección parasitaria. En este sentido, los resultados del presente estudio se pueden utilizar como una base para desarrollar programas de prevención dirigidos a los manipuladores de alimentos debido a la propagación de enfermedades a través de ellos es un problema común en todo el mundo.

Heavy Hymenolepis nana infection possibly through organic foods: report of a case.

We encountered a patient with heavy Hymenolepis nana infection. The patient was a 44-year-old Korean man who had suffered from chronic hepatitis (type B) for 15 years. A large number of H. nana adult worms were found during colonoscopy that was performed as a part of routine health screening. The parasites were scattered throughout the colon, as well as in the terminal ileum, although the patient was immunocompetent. Based on this study, colonoscopy may be helpful for diagnosis of asymptomatic H. nana infections.

A case report of Hymenolepis diminuta infection in a Malaysian child.

We report a case of Hymenolepis diminuta infection in a 2-year-old Malaysian child. This case was initially reported as 'normal' after the examination of proglottids shed from the anus of the child at a private laboratory on two occasions. The putative proglottids shed was then referred to the Parasite Southeast Asia Diagnostic (Para:SEAD) Laboratory, Department of Parasitology, Faculty of Medicine, University of Malaya for further examination. Microscopic examination confirmed that the child was infected with H. diminuta based on the characteristic eggs found in the proglottids. She was treated with a single dose praziquantel (20 mg/kg of body weight) and recovered well.

[Evaluation of epidemiological situation of cestode infections in Poland in the years 1997-2006 on the basis of data from san-epid stations]. / Analiza sytuacji epidemiologicznej tasiemczyc w Polsce w latach 1997-2006 na podstawie danych z wojewódzkich stacji san-epid.

Between 1997-2006, 3,523 intestinal cestode infections were registered in Poland. Among them 2,748 were caused by Taenia saginata, 41 by T. solium, 533 by Taenia species, 20 by Hymenolepis nana, 5 by Hymenolepis diminuta, 11 by Diphyllobothrium latum, 3 by Dipylidium caninum. Moreover, 350 cases of cystic echinococcosis and 8 cases of cysticercosis were also registered. The obtained results confirmed decreasing frequency of intestinal cestodoses in Poland.

[Application of in-house enzyme immunoassay and indirect hemagglutination methods for the serologic diagnosis of cystic echinococcosis]. / Kistik ekinokokkozisin serolojik tanisinda in-house enzim immün yöntemi ve indirek hemaglütinasyon yönteminin, kullanilmasi.

It is necessary to use methods that are not only fast and easily applicable, but also safe in the diagnosis of cystic echinococcosis (CE) and monitoring the treatment. In the present study, we investigated the presence of specific Echinococcus granulosus antibodies by in-house enzyme immunoassay (ELISA) and indirect hemagglutination (IHA) tests in the sera of 64 patients who were surgically confirmed to have CE, 10 patients with various lung and liver malignancies and 20 patients with Hymenolepis nana infections. Of the 64 CE patients, 52 (81.2%) were found to be positive with IHA and 49 (76.5%) were found to be positive with ELISA (in both of the tests, > or =1/64 titers were accepted as positive), while none of the other patient groups yielded positive results. As a result, the sensitivities of in-house IHA and ELISA methods were determined to be 81.2% and 76.5%, respectively, whereas the specificities were 100% for both of the tests. There was no statistically significant difference between the methods for the detection of E. granulosus antibodies (p>0.05). It can be concluded that, the agreement between the methods could make a considerable contribution in the diagnosis and postoperative follow-up of the CE patients.

Human infection with Hymenolepis diminuta: case report from Spain.

We report a case of Hymenolepis diminuta infection in a human. The patient was a 5-year-old girl referred to us through the onset of a cyanotic attack. Treatment with a single dose (10 mg/kg of body weight) of praziquantel was ineffective, but the parasite was eradicated after three treatment cycles with the same drug at dosages of 25 mg/kg/day for 5 days.