An interesting pathologic finding in cerebral sparganosis Wang P et al. CLINICS 2012;67(7):849-851 Figure 2 - A live tapeworm with the scolex, measuring approximately 12 cm in length, extracted from the patient (arrow). DISCUSSION The clinical manifestations of cerebral sparganosis include seizure, hemiparesis, and headache with a chronic course, in which seizure is the most common symptom (1,4). In our case, the patient first presented with sensation disorders on her right side and later with seizure. Serum ELISA is sensitive against sparganum and was essential evidence in our patient’s diagnosis. The characteristics of cerebral sparganosis on MRI include the following: A) degeneration of the cerebral white matter with edema and ventricle dilation; B) a contrast-enhanced lesion with an irregular shape, a string-of-beads shape or tunneling signs; and C) local or contralateral migration of the lesion or a change of the shape in follow-up MRI studies (1-2,5-6). Migration may suggest a live tapeworm (1,7-8), which was observed and confirmed in this case. Other infectious granulomas, primary or secondary neoplasms, chronic infarctions, and degenerative diseases should be excluded from the diagnosis (4). Rengarajan et al. (9) indicated that cerebral sparganosis mimicked a tuberculoma on imaging, which should be included in the differential diagnosis. The patient in this case was previously diagnosed with encephalitis, which should also be included in the differential diagnosis. The main pathologic findings in cerebral sparganosis include larval cestodes with a brush border and eosinophilic smooth muscle fibers and granulomas with calcareous bodies surrounded by plasma cells and eosinophils (1,6-8,10). In our case, a new tunnel-like structure with infiltrating plasma cells and eosinophils was found in addition to the previously mentioned structures. Calcareous bodies were also observed within the tunnel under higher power. This tunnel-like structure was most likely the migration path of the spar- ganum, suggesting that migration phenomena may be significant histological evidence. Neurocysticercosis is the most common parasitic disease of the human central nervous system, and it should be considered as a very important differential diagnosis in cases such as the present one. Similar to cerebral sparga- nosis, neurocysticercosis typically develops following oral ingestion of the parasite, and seizures and headache are the most commonly encountered symptoms (11). However, several factors can differentiate between the two infections: A) there are some highly suggestive radiological findings for neurocysticercosis, such as cyst structures (containing a scolex), enhancing lesions, and parenchymal calcifications (12); B) the detection of Taenia solium antigens or anti-T. solium antibodies in serum or cerebrospinal fluid can suggest the presence of neurocysticercosis (13); and C) cysticerci in different stages that are associated with inflammatory responses can be found upon microscopic examination. 850 Figure 3 - Histological findings of the larval cestode and lesion. (A) Photomicrograph of the live larval showing a brush border and eosinophilic smooth muscle fibers (H&E 4X). (B) Photomicrograph showing calcareous bodies (H&E 40X). (C) A tunnel-like structure surrounded by plasma cells and eosinophils. (H&E 10X). (D) Calcareous bodies were observed within the tunnel. (H&E 20X). Surgical resection of the lesion, including the tapeworm and the granuloma, is considered to be an effective treatment for cerebral sparganosis. Patients with total lesion excision can achieve good long-term outcomes (1). Many researchers (1-2,7-8) recommend surgery for patients with a live worm and signs of migration on MR images because this can prevent further damage caused by disease progression. Drug therapy, such as praziquantel, has a limited effect because live tapeworms are not affected (1). In this case, the operation was performed because local migration that was suggestive of a live worm was observed on serial MR images. The patient’s symptoms disappeared, and recurrence was not observed over a follow-up period of more than two years. In conclusion, the observed migration was an important radiological sign for preoperative diagnosis, identification of tapeworm survival, and judgment of surgical indication. The tunnel-like structure demonstrated by pathology might be an important diagnostic clue for cerebral sparganosis. AUTHOR CONTRIBUTIONS Wang P drafted the manuscript, reviewed the literature, and participated in the operation. Su XY made the histopathologic diagnosis. Mao Q and Liu YH performed the operation and revised the manuscript. REFERENCES 1. Kim DG, Paek SH, Chang KH, Wang KC, Jung HW, Kim HJ, et al. Cerebral sparganosis: clinical manifestations, treatment, and outcome. J Neurosurg. 1996;85(6):1066-71. 2. Moon WK, Chang KH, Cho SY, Han MH, Cha SH, Chi JG, et al. Cerebral sparganosis: MR imaging versus CT features. Radiology. 1993;188(3):751- 7. 3. Cho SY, Bae JH, Seo BS. Some Aspects Of Human Sparganosis In Korea. Kisaengchunghak Chapchi. 1975;13(1):60-77. 4. Chang KH, Chi JG, Cho SY, Han MH, Han DH, Han MC. Cerebral sparganosis: analysis of 34 cases with emphasis on CT features. Neuroradiology. 1992;34(1):1-8, http://dx.doi.org/10.1007/BF00588423. 5. 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