Molecular Diagnosis of Taenia Saginata and Solium

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.

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.