Molecular Diagnosis of Taenia Saginata and Solium

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Questions and Answers

What is a limitation of specific molecular diagnostic methods for Echinococcus Granulosus?

Lack of DNA probes

Technical complexity (correct)

Unavailability of PCR

Inadequate ultrasound staging

What is the treatment of choice for complicated Echinococcus Granulosus?

PAIR

Ultrasound staging

Albendazole therapy

Surgery (correct)

What is the purpose of using 0.5% silver nitrate or 2.7% sodium chloride during PAIR?

To prevent secondary peritoneal echinococcosis (correct)

To enhance ultrasound imaging

To kill the parasite

To inject scolicidal agent

What is the significance of a negative CFT test after surgical removal of cysts?

Has a better prognostic value Signup and view all the answers

What is the percentage of generalized eosinophilia that may be observed in blood examination?

20-25% Signup and view all the answers

What is the purpose of using acid-fast staining or lactophenol cotton blue (LPCB) staining?

To demonstrate excretion of scolices Signup and view all the answers

Why is albendazole initiated 4 days before PAIR?

To enhance the effectiveness of PAIR Signup and view all the answers

What is the scolicidal agent usually used during PAIR?

95% ethanol Signup and view all the answers

What percentage of adult-onset epilepsy is caused by neurocysticercosis?

70% Signup and view all the answers

What is the most common cause of intracranial space-occupying lesions (ICSOLs) in India?

Tuberculosis Signup and view all the answers

Which of the following is NOT a clinical feature of neurocysticercosis?

Diarrhea Signup and view all the answers

What is the purpose of the formol-ether sedimentation method in stool examination for Taenia?

To detect eggs Signup and view all the answers

How can species identification be done in Taenia Saginata and Taenia Solium?

By examining proglottids with a hand lens Signup and view all the answers

What is the advantage of antigen capture ELISA over microscopy for detecting Taenia in feces?

Higher sensitivity Signup and view all the answers

What is the purpose of demonstrating unarmed scolex in Taenia Saginata diagnosis?

To establish definitive diagnosis Signup and view all the answers

What is the definitive diagnosis of cysticercosis?

Biopsy of the lesion and microscopic examination Signup and view all the answers

What is the limitation of antigen capture ELISA for detecting Taenia in feces?

Cannot differentiate between T. saginata and T. solium Signup and view all the answers

What is the drug of choice for intestinal taeniasis?

Praziquantel Signup and view all the answers

What is the treatment for symptomatic cerebral cysticercosis?

Praziquantel in a dose of 50 mg/kg in three divided doses Signup and view all the answers

What is the life cycle of Taenia solium?

Pork tapeworm that infects humans through undercooked meat Signup and view all the answers

How can cysticercosis be prevented?

Through proper cooking of meat Signup and view all the answers

What is the characteristic appearance of cysticercal lesions on CT scan?

Small hypodensities with a bright central spot Signup and view all the answers

What is the best method for detecting dead calcified cysts in the brain?

CT scan of the brain Signup and view all the answers

What is the cause of hydatid disease?

Echinococcus spp Signup and view all the answers

Study Notes

Molecular Diagnosis of Taenia Saginata and Taenia Solium

DNA probes and PCR are used to detect and differentiate between eggs and proglottids of T. saginata and T. solium.
These techniques can also differentiate between the two subspecies of T. saginata, T. saginata saginata and T. saginata asiatica.

Diagnosis of Cysticercosis

Definitive diagnosis is by biopsy of the lesion and its microscopic examination to show the invaginated scolex with suckers and hooks.
Imaging methods:
- X-ray: detects calcified cysticerci in subcutaneous tissue and muscles, particularly in the buttocks and thigh.
- CT scan: detects dead calcified cysts in the brain.
- MRI scan: detects noncalcified cysts and ventricular cysts, and demonstrates spinal cysticerci.

Treatment of Intestinal Taeniasis and Cysticercosis

Intestinal taeniasis: single dose of praziquantel (10-20 mg/kg) or niclosamide (2 g) is the drug of choice.
Cysticercosis: excision is the best method, wherever possible. For symptomatic cerebral cysticercosis, praziquantel and albendazole may be administered.

Echinococcus spp

Causes hydatid disease, with four species known to infect humans: E. granulosus, E. multilocularis, E. oligarthrus, and E. vogeli.
E. granulosus causes cystic hydatid disease.

Diagnosis of Echinococcosis

CFT: not very sensitive and may give false-positive reactions in those receiving neural antirabic vaccine.
Antigen detection: specific echinococcal antigen in sera and in CSF can be detected by double diffusion and counter immunoelectrophoresis (CIEP) technique.
Blood examination: may reveal a generalized eosinophilia of 20-25%.
Excretion of scolices: may be observed in pulmonary or renal cysts.

Molecular Diagnostic Methods for Echinococcosis

Specific molecular diagnostic methods have been developed involving DNA probes and PCR, but their application is limited by their technical complexity.

Treatment of Echinococcosis

Traditionally surgical removal was considered as the best mode of treatment of cysts.
Currently, ultrasound staging is recommended and management depends on the stage.
In early stages, treatment of choice is puncture, aspiration, injection, and respiration (PAIR).
Albendazole is initiated 4 days before the procedure and continued for 4 weeks afterwards.

Neurocysticercosis

About 70% of adult-onset epilepsy is due to neurocysticercosis.
It is considered as the second most common cause of intracranial space occupying lesion (ICSOL) after tuberculosis in India.
Other clinical features of neurocysticercosis include increased intracranial tension, hydrocephalus, psychiatric disturbances, meningoencephalitis, transient paresis, behavioral disorders, aphasia, and visual disturbances.

Laboratory Diagnosis of Taenia Saginata and Taenia Solium

Stool examination: eggs can be detected by microscopic examination of feces, and species identification cannot be made from the eggs.
Proglottids: species identification can be done by examining with hand lens.
Scolex: definitive diagnosis can also be established by demonstration of unarmed scolex in case of T. saginata after anthelmintic treatment.
Detection of Taenia antigen in feces: antigen capture enzyme-linked immunosorbent assay (ELISA) is employed to detect coproantigen in feces.

Serodiagnosis of Taenia Saginata and Taenia Solium

Specific antibodies to adult stage antigen in serum can be demonstrated by ELISA, indirect immunofluorescence test, and indirect hemagglutination (IHA) test.

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Description

Learn about the molecular diagnosis of Taenia saginata and solium, including the use of DNA probes and PCR to detect and differentiate between eggs and proglottids. Also, discover the diagnosis of cysticercosis through biopsy and imaging methods.