Visualization of hydatid elements: comparison of several techniques

A Comparative Evaluation of Four Different Immunoassays in the Diagnosis of Cystic Echinococcosis Using a Crude and Purified Hydatid Cyst Fluid Antigen

PURPOSE

Cystic echinococcosis (CE) is one of the most neglected tropical diseases as per WHO which has an immense public health significance. Diagnosis of CE is difficult as specific clinical signs are manifested only after the hydatid cyst attains a considerable size. Immunodiagnosis is a reliable method of diagnosing CE.

METHODS

SDS-PAGE was performed for the hydatid cyst fluid antigens. The antigen purity was tested by Western blotting and four different immunoassays were evaluated using these two antigens in sheep and buffalo in diagnosis of CE.

RESULTS

SDS-PAGE revealed four bands of 72, 64, 48 and 24 kDa for crude antigen and a single 72 kDa band for purified antigen. Among sheep sera, ELISA was most sensitive (70%) using crude antigen and also while using the purified antigen (80%). In case of buffaloes, ELISA, DID and CIEP were more sensitive (83.3%) using crude antigen, whereas DID and CIEP were more sensitive (83.3%) using purified antigen.

CONCLUSION

In sheep, while using the crude antigen ELISA was the most sensitive assay and IHA was the least sensitive assay. While using the purified antigen also, ELISA was the most sensitive and others were absolutely specific except for IHA being less sensitive. In buffaloes, using crude antigen, all the immunoassays CIEP, DID and ELISA were highly sensitive in diagnosing CE infection except IHA, whereas using the purified antigen, both CIEP and DID were more sensitive than ELISA and IHA which were comparatively less sensitive in detecting CE in buffalo sera.

Lethal cysticercosis in a pet rabbit

A one-year-old neutered female crossbreed rabbit died unexpectedly after initially responding to symptomatic treatment over a three-month period for recurrent gut stasis, inappetence and lethargy. Postmortem examination revealed numerous fibrous tracks within the liver from which flattish ovoid parasites could be extruded. Parasites were also found in large numbers throughout the peritoneal cavity. Histopathology confirmed verminous hepatitis with numerous parasitic granulomas within the parenchyma of the liver containing intact and degenerate parasites. The severity of the parasitic burden and associated liver damage was the presumed cause of death. Intact parasites showed morphological features consistent with Taenia pisiformis at 6–15 days postinfection. Species identification was confirmed by PCR sequence analysis. The rabbit was fed on hay sourced from a local farm, commercially available nuggets and washed vegetables. It did not graze outside. Hay contaminated with dog or fox faeces was the presumed source of infection.

Increase of Vascular Endothelial Growth Factor and Decrease of MCP-1 and Some Updated Epidemiology Aspects of Cystic Echinococcosis Human Cases in Calabria Region

We aim to investigate some of the pathogenetic mediators of the human echinococcosis and to obtain updated epidemiological findings on cases of echinococcosis in Calabria, Southern Italy. Echinococcosis diagnosis was based on imaging, serological investigations, and molecular assay. Indeed, real-time PCR indicated the presence of G2/G3 genotypes of Echinococcus granulosus complex. Regarding pathogenesis, a relevant novel tool of immune depression should be deemed the reduced level of serum MCP-1. Also, we found a previously unreported VEGF, possibly associated with neovascularization requested by the parasite cyst metabolism. Cytokine profiles suggest a bias of the immunity toward Th2 and Treg responses. Nitric oxide levels exhibited a significant decrease one week after therapy versus basal level measured before surgery and/or chemotherapy. An increase of serum total IgE class and IgG4 subclass was found in Echinococcus-positive patients versus controls. Our data demonstrated an endemic spreading, at least in the province of Catanzaro and neighboring Calabria territories, for such parasitosis with the novel issue of the number of female overcoming male cases. In conclusion, the novel findings of this study were the increased VEGF and the reduced serum MCP-1 in the studied cases, as well as the number of Echinococcus-infected females overcoming the infected males.

Mobile Diagnostics Based on Motion? A Close Look at Motility Patterns in the Schistosome Life Cycle

Imaging at high resolution and subsequent image analysis with modified mobile phones have the potential to solve problems related to microscopy-based diagnostics of parasitic infections in many endemic regions. Diagnostics using the computing power of "smartphones" is not restricted by limited expertise or limitations set by visual perception of a microscopist. Thus diagnostics currently almost exclusively dependent on recognition of morphological features of pathogenic organisms could be based on additional properties, such as motility characteristics recognizable by computer vision. Of special interest are infectious larval stages and "micro swimmers" of e.g., the schistosome life cycle, which infect the intermediate and definitive hosts, respectively. The ciliated miracidium, emerges from the excreted egg upon its contact with water. This means that for diagnostics, recognition of a swimming miracidium is equivalent to recognition of an egg. The motility pattern of miracidia could be defined by computer vision and used as a diagnostic criterion. To develop motility pattern-based diagnostics of schistosomiasis using simple imaging devices, we analyzed Paramecium as a model for the schistosome miracidium. As a model for invasive nematodes, such as strongyloids and filaria, we examined a different type of motility in the apathogenic nematode Turbatrix, the "vinegar eel." The results of motion time and frequency analysis suggest that target motility may be expressed as specific spectrograms serving as "diagnostic fingerprints."

Cystic Echinococcosis

Echinococcosis is one of the 17 neglected tropical diseases (NTDs) recognized by the World Health Organization. The two major species of medical importance are Echinococcus granulosus and Echinococcus multilocularis. E. granulosus affects over 1 million people and is responsible for over $3 billion in expenses every year. In this minireview, we discuss aspects of the epidemiology, clinical manifestations, and diagnosis of cystic echinococcosis or cystic hydatid disease caused by E. granulosus.

Staining of hydatid elements: a useful adjunct in the diagnosis of hydatid disease

Staining techniques have immeasurably aided diagnosis of hydatid disease on several instances. The use of staining techniques for their ability to aid in the morphological diagnosis of hydatid elements, especially at rare and uncommon sites, is discussed.

Identification criteria of the rare multi-flagellate Lophomonas blattarum: comparison of different staining techniques

Bronchopulmonary lophomoniasis (BPL) is an emerging disease of potential importance. BPL is presented by non-specific clinical picture and is usually accompanied by immunosuppression. Culture of Lophomonas blattarum is difficult and its molecular diagnosis has not yet been developed. Therefore, microscopic examination of respiratory samples, e.g., bronchoalveolar lavage (BAL) or sputum, is the mainstay of BPL diagnosis. Creola bodies and ciliocytophthoria are two forms of bronchial cells which occur in chest diseases with non-specific clinical picture like that of BPL. Both forms could be misrecognized as multi-flagellates because of their motile cilia in the wet mounts and due to shape variability of L. blattarum in stained smears. The aim of the study is to compare different staining techniques for visualizing L. blattarum to improve the recognition and diagnosis of BPL, to distinguish respiratory epithelial cells from L. blattarum and to decide which stain is recommended in suspected cases of BPL. BAL samples from patients which contain L. blattarum, creola bodies, and ciliocytophthoria were collected then wet mounts were examined. The BAL samples were also stained by Papanicolaou (PAP), Giemsa, hematoxylin and eosin (H & E), trichrome, Gram, and Diff-Quik (DQ) stains. The different staining techniques were compared regarding the stain quality. In wet mounts, the ciliary movement was coordinate and synchronous while the flagellar movement was wavy and leaded to active swimming of L. blattarum. In stained slides, bronchial cells were characterized by the presence of basal nucleus and the terminal bar from which the cilia arise. Trichrome was the best stain in demonstration of cellular details of L. blattarum. H & E, PAP, and Giemsa stains showed good quality of stains. Gram and DQ stains showed only pale hues of L. blattarum. We recommended adding Wheatley's trichrome staining to the differential diagnosis workup of cases of non-specific chest infections, especially when BPL is suspected, to avoid overdiagnosis or underdiagnosis of it.

Management of serology negative human hepatic hydatidosis (caused by Echinococcus granulosus) in a young woman from Bangladesh in a resource-rich setting: A case report

Human cystic echinococcosis (hydatidosis) is a parasitic zoonosis with almost complete worldwide distribution. Echinococcus granulosus, the dog tapeworm, causes hydatidosis which accounts for 95% of human echinococcosis. Although this tapeworm is found in dogs as a definitive host and a number of intermediate hosts, humans are often infected from close contact with infected dogs. Humans are not part of the parasitic lifecycle and serve as accidental hosts. Hydatidosis is an important consideration in the differential diagnosis of hepatic cysts in individuals from endemic areas. Clinicians should be aware of the long incubation period, the high frequency of negative serological tests, and the possibility of intraoperative evaluations of the cyst aspirate being non-diagnostic. We describe a case of serology negative hydatidosis that came to medical attention as an incidental finding in a young woman from Bangladesh. The patient underwent imaging and was then started on albendazole. After several weeks of albendazole, the cyst was punctured, aspirated, injected with hypertonic saline, re-aspirated, and then fully excised. Diagnosis was confirmed by microscopic evaluation of the cyst aspirate. Serological tests for hydatidosis may be negative in patients with early disease and thus should not be used to rule out this disease. Consideration of this diagnosis allows clinicians to avoid the catastrophic spillage of cystic contents risking an anaphylactic reaction, which might prove fatal. Despite World Health Organization hydatidosis staging being based on ultrasound, radiologists in resource-rich setting may prefer MRI in the management and staging of cystic echinococcosis.

Primary hydatid cyst of the kidney and ureter with hydatiduria in a laboratory worker: a case report

Hydatid disease is frequent in endemic regions and sheep farming areas. Most common localization of hydatid cyst occurs in liver followed by lungs. Renal hydatid cyst constitutes about 2–4% of all locations. We report a case of left renal hydatid from a laboratory technician admitted in a tertiary care hospital. There were few cases of renal hydatid disease reported in India among general population but to the best of our knowledge never reported from laboratory worker. The possibility of laboratory-acquired infection cannot be ruled out in this case due to lack of precautionary measures and containment facilities in resource-constrained setting.

Differentiating Taenia eggs found in human stools: does Ziehl-Neelsen staining help?

OBJECTIVE

To determine whether Ziehl-Neelsen staining can differentiate Taenia solium from Taenia saginata eggs.

METHODS

Tapeworm proglottids (33 specimens, 23 T. solium and 10 T. saginata) and eggs (31 specimens, 13 T. solium and 18 T. saginata) were stained. Four eggs from each sample were measured and average diameters were recorded.

RESULTS

Taenia saginata eggs stained entirely magenta in seven of 13 cases. Taenia solium eggs stained entirely blue/purple in 4/18 cases and entirely magenta in one. Eggs of T. saginata were slightly larger and always ovoid, while T. solium eggs were smaller and mostly spheric.

CONCLUSIONS

Ziehl-Neelsen staining can occasionally distinguish fully mature T. solium from T. saginata eggs, but this distinction is neither very sensitive nor completely specific. Differential staining suggests differences in embryophore components between species which become evident with egg maturation. In this small series, egg morphology (shape, maximal diameter) provided appropriate differentiation between T. solium and T. saginata eggs.