Noninvasive Diagnosis of Visceral Leishmaniasis:Development and Evaluation of Two Urine-Based Immunoassays for Detection of Leishmania donovani Infection in India

Visceral leishmaniasis (VL), one of the most prevalent parasitic diseasesin the developing world causes serious health concerns. Post kala-azar dermal leishmaniasis (PKDL) is a skin disease which occurs after treatment as a sequel to VL. Parasitological diagnosis involves invasive tissue aspiration which is tedious and painful. Commercially available immunochromatographic rapid diagnostic test such as rK39-RDT is used for field diagnosis of VL, detects antibodiesin serum samples. Urine sample is however, much easier in collection,storage and handling than serum and would be a better alternative where collection of tissue aspirate or blood is impractical. In this study, we have developed and evaluated the performance of two urine-based diagnostic assays, ELISA and dipstick test, and compared the results with serologicalrK39-RDT. Our study shows the capability of urinebased tests in detecting anti-Leishmania antibodies effectively for both VL and PKDL diagnosis. The ability of dipstick test to demonstrate negative results after six months in 90% of the VL cases after treatment could be useful as a test of clinical cure. Urine-based tests can therefore replace the need for invasive practices and ensure better diagnosi

The Distribution of Toxoplasma gondii Cysts in the Brain of a Mouse with Latent Toxoplasmosis: Implications for the Behavioral Manipulation Hypothesis

reportedly manipulates rodent behavior to enhance the likelihood of transmission to its definitive cat host. The proximate mechanisms underlying this adaptive manipulation remain largely unclear, though a growing body of evidence suggests that the parasite-entrained dysregulation of dopamine metabolism plays a central role. Paradoxically, the distribution of the parasite in the brain has received only scant attention. at six months of age and examined 18 weeks later. The cysts were distributed throughout the brain and selective tropism of the parasite toward a particular functional system was not observed. Importantly, the cysts were not preferentially associated with the dopaminergic system and absent from the hypothalamic defensive system. The striking interindividual differences in the total parasite load and cyst distribution indicate a probabilistic nature of brain infestation. Still, some brain regions were consistently more infected than others. These included the olfactory bulb, the entorhinal, somatosensory, motor and orbital, frontal association and visual cortices, and, importantly, the hippocampus and the amygdala. By contrast, a consistently low incidence of tissue cysts was recorded in the cerebellum, the pontine nuclei, the caudate putamen and virtually all compact masses of myelinated axons. Numerous perivascular and leptomeningeal infiltrations of inflammatory cells were observed, but they were not associated with intracellular cysts. distribution stems from uneven brain colonization during acute infection and explains numerous behavioral abnormalities observed in the chronically infected rodents. Thus, the parasite can effectively change behavioral phenotype of infected hosts despite the absence of well targeted tropism

Aspects of clinical features, diagnosis, notification and tracing back referring to Trichinella outbreaks in North Rhine-Westphalia, Germany, 1998

52 cases of human trichinellosis were notified from 11 towns in North Rhine-Westphalia from November 1998 to March 1999. After non-typical symptoms in the enteral phase, fever, muscular ache, headache, oedema, disorder of vision and rash occurred in the parenteral phase. Trichinellosis was serologically confirmed by ELISA, IFAT or western blot. Raw sausage and minced meat produced from raw pork could be determined as probable source of infection with 44 and eight notified cases, respectively. Whereas questionable raw sausage was not available for examination, frozen minced meat from the second outbreak could be secured in households of infected people. Larvae were isolated from minced meat and were identified by PCR as Trichinella spiralis. Tracing back to the source of infection was difficult because of the long time between clinical symptoms, laboratory diagnosis and notification as well as complex trade routes for pork and its products. Trichinella cases emphasize the necessity to meet the prescribed slaughter inspection and to guarantee a reliable prove of origin for meat products especially in view of specific consumer habits, i.e. the consumption of raw meat

Aspects of clinical features, diagnosis, notification and tracing back referring to

52 cases of human trichinellosis were notified from 11 towns in North Rhine-Westphalia from November 1998 to March 1999. After non-typical symptoms in the enteral phase, fever, muscular ache, headache, oedema, disorder of vision and rash occurred in the parenteral phase. Trichinellosis was serologically confirmed by ELISA, IFAT or western blot. Raw sausage and minced meat produced from raw pork could be determined as probable source of infection with 44 and eight notified cases, respectively. Whereas questionable raw sausage was not available for examination, frozen minced meat from the second outbreak could be secured in households of infected people. Larvae were isolated from minced meat and were identified by PCR as Trichinella spiralis. Tracing back to the source of infection was difficult because of the long time between clinical symptoms, laboratory diagnosis and notification as well as complex trade routes for pork and its products. Trichinella cases emphasize the necessity to meet the prescribed slaughter inspection and to guarantee a reliable prove of origin for meat products especially in view of specific consumer habits, i.e. the consumption of raw meat

Toxoplasma gondii: 'Stadienkonversion und Reaktivierung der Infektion: Einfluss von parasitaeren und immunologischen Faktoren'. Teilprojekt: Immunhistologische und elektronenmikroskopische Analyse der Stadienkonversion Abschlussbericht

The kinetics and stage conversion of Toxoplasma gondii was studied in vivo in three different mouse strains (BALB/c, C57Bl/6, NMRI) using three strains of T. gondii (RH-virulent, NED-intermediate, Gail-non virulent) for infection. The expression of tachyzoite (TA)-specific, bradyzoite (BA)-specific, and cyst wall (CW)-specific proteins was studied by using various immunohistological and cytochemical procedures. Additional morphological studies were performed by electron microscopy. TA protein expression was found in all examined organs up to day 12 pi. BA-specific and/or CW-specific proteins appeared from day 14 pi onwards together with cyst formation. TA-specific proteins were detectable in the brains up to 30-40 days pi, in the lungs up to 14 days pi. During the acute infection stage there was a limited time of dual expression of TA-specific and BA-/or CW-specific proteins at one infection site. However, the kinetics of Toxoplasma, the parasite load, stage specific protein expression, and cyst formation seen in mice depended on the combination of murine and parasite strains used for infection. The early cyst formation in vivo and in vitro (brain-cell cultures) provided to be very similar. The expression site of an excretory 29 kDa antigen was identified cytochemically. Intermediate stages expressing both TA- and CW-specific markers were also found in the brain tissue of AIDS patients with Toxoplasma encephalitis (TE). However, neither in murine nor human brains tissue was evidence of cyst rupture. During acute TE most of the disseminating parasites expressed the TA-specific protein P30. The results of serological studies did rule out secondary infection as a possible cause for parasite dissemination in AIDS patients. The findings of a strain and host specific regulation of stage conversion and cyst formation requires defined models for use in immunological and therapeutical Toxoplasma research. (orig.)SIGLEAvailable from TIB Hannover: F98B1791 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman