Abstract

Background: Tuberculoma mimicking en-plaque meningioma is a rare variant of tuberculoma. A few cases were reported in the literature. The radiological appearance can be mistakenly diagnosed as en-plaque meningioma.

Case Description: We report a rare case of a 45-year-old male with tuberculoma mimicking en-plaque meningioma who underwent surgical excision followed by anti-tuberculosis (TB) medications. Follow-up brain imaging after three months showed a favorable outcome.

Conclusion: Tuberculoma mimicking en-plaque meningioma should be considered in the differential diagnosis where TB is endemic.

Keywords: En-plaque tuberculoma, Leptomeningeal tuberculoma, Tuberculoma, Tuberculosis

INTRODUCTION

Tuberculosis (TB) infection of the central nervous system (CNS) carries a high risk of mortality rate and can lead to serious neurological complications and long-term consequences.[ 27 ] TB infection of the CNS manifests as tuberculoma and accounts for about 1% of those cases.[ 20 ] Tuberculomas that affect the brain tissue occur more often than those that involve the dura or skull bone.[ 4 , 5 , 16 , 17 ] Most of these patients are immunocompromised.[ 20 ] Intracranial tuberculomas frequently occur as a result of tuberculous infection originating elsewhere in the body through hematogenous spread; the lung is the most common site of origin.[ 25 ] Nevertheless, the absence of an extracranial source of the illness is not unusual.[ 5 ] The symptoms and signs vary between cases based on tuberculoma locations intracranially.[ 26 ] Tuberculoma with extensive dural attachment mimicking en-plaque meningioma is a rare variant of tuberculoma that was described in the literature.[ 18 ] Obtaining a proper history, physical examination, and supportive laboratory and imaging findings are necessary to reach an appropriate diagnosis, where the definitive diagnosis is made by histology examination.[ 2 ] Anti-TB medications are universally accepted as an essential treatment for tuberculoma.[ 14 , 15 ] In this rare case, we report a 45-year-old man with tuberculoma mimicking en-plaque meningioma and reviewing the literature.

CASE REPORT

This patient is a 45-year-old male patient who was previously well and immunocompetent. He had a new onset of generalized tonic-clonic convulsion. He denied having head trauma, fever, previous similar attacks, contact with sick patients, and malignancy. Neurological examination was normal without papilledema. Initial blood investigations showed a slightly abnormal raise in white blood cells: 11.53 × 10^9/L (normal range: 4–10 × 10^9/L) and also slightly abnormal elevation erythrocyte sedimentation rate: 21 mm/hour (normal range: 0–15 mm/hour); otherwise, the rest of laboratory results were within the normal range including electrolytes and C-reactive protein [ Table 1 ]. The human immunodeficiency virus test was negative, and the routine chest X-ray was normal [ Figure 1 ].

Table 1:

Blood investigation.

Figure 1:

Chest X-ray posteroanterior view.

Computerized tomography (CT) scan of the brain without contrast showed a hypodense signal in the right frontal lobe involving the gray and white matter without mass effect or sulcal effacement that was not enhancing post-contrast administration [ Figure 2 ]. Magnetic resonance (MR) imaging of the brain post-gadolinium demonstrated an ill-defined enhancing meningeal-based lesion [ Figures 3 and 4 ]. The preoperative diagnosis was en-plaque meningioma. The lesion was explored through a right frontal craniotomy, and the overlying bone was normal. Intraoperatively, the lesion was avascular and firm yellowish-white mass that was in adherence to a thick dura. Total excision of the mass with the attached dura was performed, along with coagulating overlying bone. The bone flap was replaced after duraplasty. The wound was closed in layers after achieving a good hemostasis. Histological examination of the lesion revealed diffuse granulomatous inflammation with focal caseous necrosis consistent with TB [ Figure 5 ]. The postoperative recovery period was uneventful. The purified protein derivative (PPD) test was negative. The patient was discharged from the hospital in stable condition on anti-TB medications and phenytoin.

Figure 2:

(a) Axial CT scan without contrast and (b) post contrast axial CT scan showed right frontal lobe hypodensity.

Figure 3:

(a) Axial T1-weighted MR image , (b) axial T2-weighted MR image and (c) axial T2-weighted- fluid attenuated MR image.

Figure 4:

(a) Sagittal T1-weighted MR images , (b)axial T1-weighted MR images post gadolinium showed dural based hyperintense enhanced lesion.

Figure 5:

Microscopic image showed the histological features of tuberculoma.

At three months of follow-up visits, MR imaging of the brain showed total resection of the tuberculoma without recurrence, and the patient was well [ Figure 6 ].

Figure 6:

Axial T1-weighted magnetic resonance image post-gadolinium showed total resection of the tuberculoma with postoperative changes.

DISCUSSION

CNS TB is more frequently diagnosed in developing countries in comparison with other developed countries. [ 18 ] It may manifest as tuberculous meningitis, tuberculoma, tuberculous abscesses, and focal cerebritis.[ 6 ] CNS TB is an outcome of tubercle bacilli spread through blood vessels into meninges and brain tissue from an infected part of the body, usually the lungs, with tuberculous infection, which may explained that corticomedullary junction is the most common location of tuberculoma.[ 6 ] The reported cases of intracranial tuberculoma with an extracranial source of infection are 30–50% of all intracranial tuberculoma cases. [ 8 ] However, intracranial tuberculoma with no extracranial causes is not rare.[ 8 ] The diagnosis of intracranial tuberculoma is made based on brain imaging and clinical correlation.[ 5 ] Arseni published a case series of 201 patients with intracranial tuberculoma; 85% of patients complained of seizure, 72% of the patients had symptoms of intracranial hypertension, and 68% had focal neurological deficits.[ 3 ] The literature showed that the clinical presentation of en-plaque tuberculoma varies based on the location of the lesion.[ 1 , 5 , 9 , 10 , 18 , 21 , 24 , 30 ] The most common reported presentations are headache, vomiting, and seizure. In our reported case, he had a seizure with a normal nervous system examination; otherwise, there were no suggestive symptoms of TB infection, such as fever, respiratory symptoms, weight loss, night sweats, or recent contact with TB patients. The PPD skin test could be negative in intracranial tuberculoma as in our reported case. [ 19 ] According to our literature search, there are eight reported cases of tuberculoma mimicking en-plaque meningioma [ Table 2 ].[ 1 , 5 , 9 , 10 , 18 , 21 , 24 , 30 ] Tuberculoma has several features on CT scans and MR imaging.[ 5 ] This could be a result of the tuberculoma evolving granulomatous process. Therefore, the lesion has various imaging features according to the evolution stage.[ 28 ] In the early stage, the intracranial tuberculoma may not enhance on CT scan.[ 28 ] On MR imaging, this early lesion and edema appear hypointense on T1-weighted MR images and hyperintense on T2-weighted images.[ 13 , 23 ] In the next phase of evolution, the granulomatous stage with central necrosis, the tuberculoma showed as an isodense or slightly hyperdense with surrounding edema with variable enhancement post-contrast on CT scan.[ 29 ] On MR imaging, this later-stage tuberculoma showed similar features as in early stage on T1-weighted MR imaging. However, on T2-weighted MR imaging appear as an isointense capsule with hypointense necrotic center.[ 23 ] The lesion enhancement on CT scan and MR imaging may appear as a homogenous solid enhancement, ring enhancement, or mixed enhancement of the previously mentioned.[ 5 , 28 ] Almost 50% of intracranial tuberculomas have some attachment to the dura, but broad dural attachment mimicking en-plaque lesion is rare. [ 1 , 5 , 9 , 10 , 18 , 21 , 24 , 30 ] The tuberculoma with a dural base mimics en-plaque meningioma and is difficult to distinguish from a true meningeal neoplasm based on the imaging.[ 11 ] CT scan and MR imaging of en-plaque tuberculoma had been described as a dural-based enhancing mass, with other findings having been reported as white matter edema and sulcal enhancement. [ 7 , 10 , 22 , 30 , 31 ] In our patient, his CT imaging showed a hypodense signal in the right frontal lobe involving the gray and white matter with no mass effect or sulcal effacement that was not enhanced post the contrast administration [ Figure 2 ]. On T1-weighted MR imaging, post-gadolinium appears ill-defined dural-based hyperintense-enhanced lesion [ Figure 3 ]. The diagnosing of en-plaque tuberculoma preoperatively is challenging, especially in the absence of an extracranial source, as in our patient. The majority of reported cases were diagnosed postoperatively based on histology examination of the lesion.[ 5 , 9 , 10 , 18 , 21 , 30 ] Pathognomonic of tuberculoma diagnosis histologically is a caseous center surrounded by a granulomatous reaction.[ 12 ] Medical therapy is effective for intracranial tuberculoma.[ 18 ] The management of reported cases either by anti-TB medications and steroids or surgical excision followed by anti-TB medications. Most of the reported cases had full recovery.

Table 2:

Reported cases summery of tuberculoma mimicking en-plaque meningioma

CONCLUSION

Tuberculoma mimicking en-plaque meningioma should be considered in the differential diagnosis where TB is endemic. The anti-TB treatment is the effective management of en-plaque tuberculoma when the diagnosis is made.

Ethical approval

The Institutional Review Board approval is not required.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Use of artificial intelligence (AI)-assisted technology for manuscript preparation

The authors confirm that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript and no images were manipulated using AI.

Disclaimer

The views and opinions expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the Journal or its management. The information contained in this article should not be considered to be medical advice; patients should consult their own physicians for advice as to their specific medical needs.

References

1. Alkan A, Parlak M, Baysal T, Sıgırcı A, Kutlu R, Altınok T. En-plaque-tuberculomas-of-tentorium-in-a-pregnant-woman-followup--2003. Eur Radiol. 2003. 13: 1190-3

2. Aggarwal A, Patra DP, Gupta K, Sodhi HB. Dural tuberculoma mimicking meningioma: A clinicoradiologic review of dural en-plaque lesions. World Neurosurg. 2016. 88: 686.e1-7

3. Arseni C. Two hundred and one cases of intracranial tuberculoma treated surgically. J Neurol Neurosurg Psychiatry. 1958. 21: 308-11

4. Artico M, De Caro GM, Carloia S, Salvati M, D’Ambrosio M, Delfini R. Advances in diagnosis, treatment and prognosis of intracerebral tuberculomas in the last 50 years. Report of 21 cases. Neurochirurgie. 1999. 45: 129-33

5. Bauer J, Johnson RF, Levy JM, Pojman DV, Ruge JR. Tuberculoma presenting as an en plaque meningioma. Case report. J Neurosurg. 1996. 85: 685-8

6. Bernaerts A, Vanhoenacker FM, Parizel PM, Van Goethem JW, van Altena R, Laridon A. Tuberculosis of the central nervous system: Overview of neuroradiological findings. Eur Radiol. 2003. 13: 1876-90

7. Chang CM, Chan FL, Yu YL, Huang CY, Woo E. Tuberculous meningitis associated with meningeal tuberculoma. J R Soc Med. 1986. 79: 486-7

8. Dastur HM, Desai AD. A compartive study of brain tuberculomas and gliomas based upon 107 case records of each. Brain. 1965. 88: 375-96

9. Dubey S, Devi BI, Jawalkar VK, Bhat DI. Tuberculoma en plaque: A case report. Neurol India. 2002. 50: 497-9

10. Elisevich K, Arpin EJ. Tuberculoma masquerading as a meningioma. Case report. J Neurosurg. 1982. 56: 435-8

11. Fishbein NJ, Dillon WP, Bakovich AJ, editors. Teaching atlas of brain imaging. United States: Thieme; 2000. p.

12. Gray F. Bacterial infections. Brain Pathol. 1997. 7: 629-47

13. Gupta RK, Jena A, Singh AK, Sharma A, Puri V, Gupta M. Role of magnetic resonance (MR) in the diagnosis and management of intracranial tuberculomas. Clin Radiol. 1990. 41: 120-7

14. Harder E, Al-Kawi MZ, Carney P. Intracranial tuberculoma: Conservative management. Am J Med. 1983. 74: 570-6

15. Hejazi N, Hassler W. Multiple intracranial tuberculomas with atypical response to tuberculostatic chemotherapy: Case report and review of the literature. Neurosurg Q. 1999. 9: 154-61

16. Jacques C, Boukobza M, Polivka M, Ferrario A, George B, Merland JJ. Cranial epidural tuberculoma. A case report. Acta Radiol. 2000. 41: 367-70

17. Jamjoom ZA, Assaf HM, Hamid F, Haddad Q, Jamjoom AH, Naim-Ur-Rahman . Intracranial epidural tuberculoma presenting as a scalp swelling. Surg Neurol. 1994. 42: 322-5

18. Kumar J, Mallik J, Strickland B, Harsh V, Kumar A. Intracranial en-plaque tuberculoma impersonating en-plaque meningioma: Case report and brief review of literature. Asian J Neurosurg. 2017. 12: 576

19. Mayers MM, Kaufman DM, Miller MH. Recent cases of intracranial tuberculomas. Neurology. 1978. 28: 256-60

20. Monteiro R, Carneiro JC, Costa C, Duarte R. Cerebral tuberculomas-A clinical challenge. Respir Med Case Rep. 2013. 9: 34-7

21. Ng SH, Tang LM, Lui TN, Ko SF, Wong HF, Wai YY. Tuberculoma en plaque: CT. Neuroradiology. 1996. 38: 453-5

22. Okada T, Yoshida T, Asai T, Shintani A. Unusual meningeal tuberculoma-Case report. Neurol Med Chir (Tokyo). 1993. 33: 710-2

23. Salgado P, Del Brutto OH, Talamas O, Zenteno MA, Rodríguez-Carbajal J. Intracranial tuberculoma: MR imaging. Neuroradiology. 1989. 31: 299-302

24. Singh KK, Nair MD, Radhakrishnan K, Tyagi JS. Utility of PCR assay in diagnosis of en-plaque tuberculoma of the brain. J Clin Microbiol. 1999. 37: 467-70

25. Sinh G, Pandya SK, Dastur DK. Pathogenesis of unusual intracranial tuberculomas and tuberculous space-occupying lesions. J Neurosurg. 1968. 29: 149-59

26. Teoh R, Humphries MJ, O’Mahony G. Symptomatic intracranial tuberculoma developing during treatment of tuberculosis: A report of 10 patients and review of the literature. Q J Med. 1987. 63: 449-60

27. Uysal G, Köse G, Güven A, Diren B. Magnetic resonance imaging in diagnosis of childhood central nervous system tuberculosis. Infection. 2001. 29: 148-53

28. Vengsarkar US, Pisipaty RP, Parekh B, Panchal VG, Shetty MN. Intracranial tuberculoma and the CT scan. J Neurosurg. 1986. 64: 568-74

29. Weisberg L, Nice C, editors. Cerebral computed tomography. Philadelphia, PA: Saunders; 1988. p.

30. Welchman JM. Computerized tomography of intracranial tuberculomata. Clin Radiol. 1979. 30: 567-73

31. Witrak BJ, Ellis G. Intracranial tuberculosis: Manifestations on computerized tomography. South Med J. 1985. 78: 386-92