Imaging Case Answer: Neurocysticercosis

The diagnosis of Neurocysticercosis was made by the radiologist by the initial CT head without contrast given the pathognomonic findings of the collodial vesicular stage of the disease. An MRI of the brain was obtained the next day. T1, T2, and FLAIR images shown below, respectively:

 


 

Cause:

  • Neurocysticercosis, is caused by the porcine tapeworm Taenia Solium.  It is endemic in Central/South America, Asia, and. Africa.  It is transmitted via the fecal-oral route, or by ingestion of eggs after consuming undercooked pork or contaminated water

 Presentation on imaging depends on the stage of infection:

  • Vesicular: Cyst with dot sign. In CT below, presents as cystic lesions with “scolex” in the center as well as edema and calcifications.

 

  • Colloidal vesicular: Most symptomatic stage. The cyst and the wall become thickened and enhance, there is often marked surrounding edema.

  • Granular Nodular: Cyst begins to diminish in size, edema remains present enhancement persists but is less prominent than the colloidal vesicular stage. Similar to above image.
  • Nodular calcified: Appears as small non-reactive calcification without edema


Imaging of choice:

  • MRI for diagnosis and for more detailed information to aid in staging. Of note diagnosis can also be made via CT alone if neurocysticercosis is found in the most prominent stages

Differential Diagnosis of Imaging:

  • Cerebral Metastasis
  • Cerebral Abscess
  • Tuberculoma
  • Amoebic Encephalitis
  • Other parasitic images

Treatment:

  • Praziquantel: 50mg/kg/day for two weeks, OR
  • Albendazole: 15/mg/kg/day (max 800mg/day) for 8-30 days
  • Co-administer with IV steroid for prophylaxis against intracranial edema/hypertension, which can increase during death of the larvae with treatment
  • Often co-administered with seizure prophylaxis such as Keppra
  • Occasionally, surgical removal of cysts

Disposition:

  • Generally ICU for neuro-monitoring during initial stage of treatment or if patient has severe neurologic findings including seizures

References:

  • A comprehensive review of imaging findings in human cysticercosis. Venkat B, Aggarwal N, Makhaik S, Sood R. J Radiol. 2016 Apr;34(4):241-57.
  • Current consensus guidelines for treatment of neurocysticercosis. García HH, Evans CA, Nash TE, Takayanagui OM, White AC Jr, Botero D, Rajshekhar V, Tsang VC, Schantz PM, Allan JC, Flisser A, Correa D, Sarti E, Friedland JS, Martinez SM, Gonzalez AE, Gilman RH, Del Brutto OH. Clin Microbiol Rev. 2002 Oct;15(4):747-56.