Abdominal angiostrongyliasis can be diagnosed with a immunochromatographic rapid test with recombinant galactin from Angiostrongylus cantonensis.

Angiostrongylus costaricensis is the causative agent of abdominal angiostrongyliasis, a zoonotic infection that may produce severe eosinophilic enterocolitis or hepatitis in humans. Parasites are usually not released in stools and serology has an important role in diagnosis. Since cross-reactivity is demonstrated between A. costaricensis and another metastrongylid worm, A. cantonensis, we tested heterologous recombinant galectin as a probe in an immunochromatographic rapid diagnostic test (ICT-RDT) for detection of anti-A. costaricensis antibodies. Almost all (11/12) positive control sera from A. costaricensis infected patients were positive at ICT RDT. These are preliminary indications that r-galectin ICT-RDT is useful for diagnosing A. costaricensis infection.

Abdominal angiostrongyliasis can be diagnosed with a immunochromatographic rapid test with recombinant galactin from Angiostrongylus cantonensis

Angiostrongylus costaricensis is the causative agent of abdominal angiostrongyliasis, a zoonotic infection that may produce severe eosinophilic enterocolitis or hepatitis in humans. Parasites are usually not released in stools and serology has an important role in diagnosis. Since cross-reactivity is demonstrated between A. costaricensis and another metastrongylid worm, A. cantonensis, we tested heterologous recombinant galectin as a probe in an immunochromatographic rapid diagnostic test (ICT-RDT) for detection of anti-A. costaricensis antibodies. Almost all (11/12) positive control sera from A. costaricensis infected patients were positive at ICT RDT. These are preliminary indications that r-galectin ICT-RDT is useful for diagnosing A. costaricensis infection.

Revealing genetic hybridization and DNA recombination of Fasciola hepatica and Fasciola gigantica in nuclear introns of the hybrid Fasciola flukes.

Fasciola hepatica and F. gigantica are ruminant liver flukes that are found worldwide. They can occur sympatrically and hybridize, consequently producing an intermediate form (Fasciola sp.), especially in Africa and Asia. The bridge intron (TkBridgeInt) and intron 4 of domain 2 (TkD2Int4) of the taurocyamine kinase gene were cloned and sequenced from 14 F. hepatica, 18 F. gigantica, and 12 Fasciola sp. These intron regions could be used to differentiate F. hepatica from F. gigantica and revealed genetic hybridization and DNA recombination between F. hepatica and F. gigantica in Fasciola sp. from Japan and Bangladesh. Two specimens of F. hepatica from Ecuador revealed cryptic diversity. A combination of three haplotypes observed in a Fasciola sp. specimen from Japan suggested triploidy. Thus, the intron region of the taurocyamine kinase gene is a potential marker for detecting the hybrid status of the Fasciola flukes.

Molecular detection of Schistosoma japonicum in infected snails and mouse faeces using a real-time PCR assay with FRET hybridisation probes.

A real-time polymerase chain reaction (PCR) assay with fluorescence resonance energy transfer (FRET) hybridisation probes combined with melting curve analysis was developed to detect Schistosoma japonicum in experimentally infected snails and in faecal samples of infected mice. This procedure is based on melting curve analysis of a hybrid between an amplicon from the S. japonicum internal transcribed spacer region 2 sequence, which is a 192-bp S. japonicum-specific sequence, and fluorophore-labelled specific probes. Real-time FRET PCR could detect as little as a single cercaria artificially introduced into a pool of 10 non-infected snails and a single egg inoculated in 100 mg of non-infected mouse faeces. All S. japonicum-infected snails and all faecal samples from infected mice were positive. Non-infected snails, non-infected mouse faeces and genomic DNA from other parasites were negative. This assay is rapid and has potential for epidemiological S. japonicum surveys in snails, intermediate hosts and faecal samples of final hosts.

Molecular detection of Schistosoma japonicum in infected snails and mouse faeces using a real-time PCR assay with FRET hybridisation probes

A real-time polymerase chain reaction (PCR) assay with fluorescence resonance energy transfer (FRET) hybridisation probes combined with melting curve analysis was developed to detect Schistosoma japonicum in experimentally infected snails and in faecal samples of infected mice. This procedure is based on melting curve analysis of a hybrid between an amplicon from the S. japonicum internal transcribed spacer region 2 sequence, which is a 192-bp S. japonicum-specific sequence, and fluorophore-labelled specific probes. Real-time FRET PCR could detect as little as a single cercaria artificially introduced into a pool of 10 non-infected snails and a single egg inoculated in 100 mg of non-infected mouse faeces. All S. japonicum-infected snails and all faecal samples from infected mice were positive. Non-infected snails, non-infected mouse faeces and genomic DNA from other parasites were negative. This assay is rapid and has potential for epidemiological S. japonicum surveys in snails, intermediate hosts and faecal samples of final hosts.

Specificity of immunoblotting analyses in eosinophilic meningitis.

Angiostrongylus cantonensis and Gnathostoma spinigerum are the two most common causative parasites of eosinophilic meningitis (EOM). Serological tests are helpful tools for confirming the identity of the pathogen. Recent reports determined the specificity of such tests by using normal healthy controls. There have been limited studies done to rule out the cross-reactivity between these two causative parasites of EOM. This study aims to assess the specificity of the serological test in EOM by using each condition as a control for the other. Thirty-three patients with a diagnosis of EOM were enrolled. Sera from 22 patients with a positive 29-kDa antigenic diagnostic band of A. cantonensis were tested for the 21 and 24-kDa antigenic bands of G. spinigerum. Similarly, sera of 11 gnathostomiasis patients were tested for the 29-kDa diagnostic band for A. cantonensis. Only one patient in the angiostrongyliasis group had a positive result for the 21 and 24-kDa antigenic bands of G. spinigerum, while no gnathostomiasis patients showed a positive result for the 29-kDa antigenic band of A. cantonensis. The specificity of the 21 and 24-kDa antigenic bands for gnathostomiasis and the 29-kDa antigenic band for A. cantonensis was 95.5% and 100%, respectively. The antigenic bands for the diagnosis of gnathostomiasis and angiostrongyliasis in EOM were highly specific.

Specificity of immunoblotting analyses in eosinophilic meningitis

Angiostrongylus cantonensis and Gnathostoma spinigerum are the two most common causative parasites of eosinophilic meningitis (EOM). Serological tests are helpful tools for confirming the identity of the pathogen. Recent reports determined the specificity of such tests by using normal healthy controls. There have been limited studies done to rule out the cross-reactivity between these two causative parasites of EOM. This study aims to assess the specificity of the serological test in EOM by using each condition as a control for the other. Thirty-three patients with a diagnosis of EOM were enrolled. Sera from 22 patients with a positive 29-kDa antigenic diagnostic band of A. cantonensis were tested for the 21 and 24-kDa antigenic bands of G. spinigerum. Similarly, sera of 11 gnathostomiasis patients were tested for the 29-kDa diagnostic band for A. cantonensis. Only one patient in the angiostrongyliasis group had a positive result for the 21 and 24-kDa antigenic bands of G. spinigerum, while no gnathostomiasis patients showed a positive result for the 29-kDa antigenic band of A. cantonensis. The specificity of the 21 and 24-kDa antigenic bands for gnathostomiasis and the 29-kDa antigenic band for A. cantonensis was 95.5 percent and 100 percent, respectively. The antigenic bands for the diagnosis of gnathostomiasis and angiostrongyliasis in EOM were highly specific.

Peripheral eosinophilia as an indicator of meningitic angiostrongyliasis in exposed individuals.

The diagnosis of meningitic angiostrongyliasis (MA) is based on clinical criteria. A lumbar puncture is used as a diagnostic tool, but it is an invasive procedure. The blood eosinophil levels are also assessed and used in the diagnosis of this disease. We enrolled 47 patients with serologically proven MA and 131 controls with intestinal parasite infections. An absolute eosinophil count model was found to be the best marker for MA. An eosinophil count of more than 798 cells led to sensitivity, specificity, positive predictive and negative predictive values of 76.6%, 80.2%, 58.1% and 90.5%, respectively. These data support the use of testing for high blood eosinophil levels as a diagnostic tool for MA in individuals that are at risk for this disease.

Peripheral eosinophilia as an indicator of meningitic angiostrongyliasis in exposed individuals

The diagnosis of meningitic angiostrongyliasis (MA) is based on clinical criteria. A lumbar puncture is used as a diagnostic tool, but it is an invasive procedure. The blood eosinophil levels are also assessed and used in the diagnosis of this disease. We enrolled 47 patients with serologically proven MA and 131 controls with intestinal parasite infections. An absolute eosinophil count model was found to be the best marker for MA. An eosinophil count of more than 798 cells led to sensitivity, specificity, positive predictive and negative predictive values of 76.6 percent, 80.2 percent, 58.1 percent and 90.5 percent, respectively. These data support the use of testing for high blood eosinophil levels as a diagnostic tool for MA in individuals that are at risk for this disease.