Thalamic Tuberculoma Presenting as Isolated Gait Disturbance Without Systemic or Meningeal Symptoms in a 2-Year-Old Child: A Case Report

Abstract

Introduction

Intracranial tuberculoma is an important manifestation of pediatric central nervous system tuberculosis, especially in endemic regions. While seizures and signs of raised intracranial pressure are common presenting features, isolated focal neurological deficits without systemic or meningeal symptoms are rare, resulting in diagnostic delay. We report an unusual case of thalamic tuberculoma presenting primarily with gait disturbance in a young child.

Case Presentation

A 2-year-old boy from Karachi, Pakistan, presented with inability to walk independently at 20 months age. On neurological examination, he had decreased power involving left side of body. MRI of the brain showed a ring-enhancing lesion in the right thalamus extending into the midbrain with surrounding vasogenic edema. Magnetic resonance spectroscopy (MRS) showed a lipid/lactate peak, which supported an infectious granulomatous etiology; a presumptive diagnosis of tuberculoma was made based on imaging findings and household TB exposure.

Discussion

Although intracranial tuberculoma does not always present with systemic manifestations of tuberculosis in children, as observed in the present study, it is also a challenging disease to diagnose in young children due to the atypical presentation. Neuroimaging: Early diagnosis is possible. For deep-seated lesions where operative therapy and surgical treatment are highly risky, conservative management is often effective with anti-tuberculous therapy and adjunctive corticosteroids. Early physiotherapy to achieve functional recovery is very important.

Conclusion

The case illustrates the need for consideration of intracranial tuberculoma in an individual neurological impairment case, considering children with isolated neurological deficits, when systemic forms of tuberculosis do not develop, even in the absence of evidence of systemic tuberculosis symptoms and history of direct exposure. Prompt imaging, early diagnosis, and treatment with anti-tuberculous therapy may lead to good outcomes.

Introduction

Central nervous system (CNS) tuberculosis is still a significant cause of neurologic morbidity in children, especially in tuberculosis-endemic areas. Pakistan has the fifth-highest tuberculosis burden globally, accounting for approximately 6.3% of global TB cases in 2024.¹ Intracranial tuberculomas, granulomatous lesions due to hematogenous dissemination of Mycobacterium tuberculosis, constitute a significant proportion of space-occupying brain lesions in developing countries. Their clinical characteristics vary widely, depending on the lesion’s location, size, and associated edema.² Among pediatric populations, intracranial tuberculomas commonly present with seizures, increased intracranial pressure, or focal neurological deficits. Yet isolated movement or gait disturbances without systemic or meningeal signs remain remarkably rare, making rapid detection difficult.³ The thalamus and brainstem are considered deeply situated regions where lesions can cause subtle or atypical neurological findings, particularly in very young children.⁴ Neuroimaging is crucial for the diagnosis of CNS tuberculosis, particularly in identifying intracranial tuberculomas. Although diagnosis remains dependent on the overall clinical picture, definitive bacteriological confirmation is not possible in all cases.⁵ However, in the absence of systemic evidence of tuberculosis, distinguishing intracranial tuberculoma from neoplastic lesions remains difficult, as radiological features may be non-specific and histopathologic confirmation may sometimes be required.⁶ Management is generally conservative with anti-tuberculous therapy (ATT) and adjunctive corticosteroids, especially for deep-seated lesions where surgical resolution is of high risk.⁷ Most pediatric cases yield favorable neurological outcomes with early treatment.⁸ Here, we report a rare case of thalamic tuberculoma seen in a 2-year-old child who presents only with delayed milestone of independent walking and mild hemiparesis, without systemic or meningeal symptoms of tuberculosis, emphasizing the importance of maintaining high clinical suspicion in endemic settings.

Case Presentation

A 2-year-old boy from Karachi, Pakistan presented with difficulty walking alone and was dependent upon assistance in ambulation. He also complained of weak grip on his left hand. The weakness appeared to be non-progressive over the preceding 2 months, and there was no history of seizures, fever, vomiting, altered consciousness, or meningeal symptoms. The child was born by normal vaginal delivery, cried immediately at birth, and had no perinatal problems. Age-appropriate developmental milestones were reported, including timely immunizations (BCG at birth). There was no history of congenital tuberculosis, and no family history of active tuberculosis at presentation or in past 2 years.

On clinical evaluation, the child had stable vital signs. The child was afebrile with heart rate 96 beats per minute, respiratory rate 35 breaths per minute, capillary refill time less than 3 seconds, and oxygen saturation in room air 98%. On examination, the fronto-occipital circumference (FOC) was 47 cm (at 75^th centile) with weight 7 kg (<3^rd centile). Motor examination findings showed normal tone and reflexes in all limbs. Right-sided muscle power was normal, with strength graded as 5/5 in both the right upper and lower limbs. On the left side, there was a mild reduction in muscle power, graded as 4/5 in both the upper and lower limbs. Cranial and cerebellar examination was unremarkable. Gait examination revealed clumsy walking with support. Motor and sensory functions were otherwise intact. After history and examination, a provisional diagnosis of space occupying lesion was made.

Magnetic resonance imaging (MRI) of the brain (Figure 1) demonstrated an area of contrast enhancement with surrounding vasogenic edema. A ring-enhancing lesion in the right thalamus extending into the midbrain, measuring ∼ 2.1 × 1.8 × 2.8 cm, with surrounding vasogenic edema causing mild mass effect on the third ventricle and lateral ventricular dilatation, without diffusion restriction (Figure 2). Sagittal imaging confirmed superior and inferior extension of the lesion into the midbrain (Figure 3). MRS demonstrated an elevated lipid/lactate peak and reduced N-acetylaspartate (Figure 4). This pattern supports an infectious or necrotic process but is not specific for tuberculosis. In tuberculoma, the lipid/lactate peak is typically prominent, whereas in high-grade gliomas, the choline peak is elevated with an increased choline/creatinine ratio. Chest X-ray and routine laboratory tests, such as the ESR and CBC, were normal. Tuberculin skin test was positive with induration >10mm.⁹ Gastric aspirate for AFB was not done as child had no signs of pulmonary tuberculosis. Hhousehold screening revealed latent TB in all family members except the father.

Figure 1.

Coronal T1-weighted post-contrast MRI showing a ring-enhancing lesion (arrow) centered in the right thalamus with extension toward the midbrain. Mild surrounding vasogenic edema and associated local mass effect are present.

Figure 2.

Axial T2-weighted MRI demonstrating a right thalamic lesion (arrow) with surrounding T2 hyperintense vasogenic edema, causing mild mass effect on the third ventricle and mild ventricular dilatation.

Figure 3.

Sagittal T1-weighted post-contrast MRI demonstrating superior–inferior extension of the right thalamic lesion into the midbrain (arrow) with associated mild local mass effect.

Figure 4.

Proton MR spectroscopy (MRS) demonstrating reduced N-acetylaspartate and a lipid/lactate peak, findings supportive of an infectious granulomatous process.

In our patient, the dominant lipid/lactate peak with absence of diffusion restriction, together with the ring-enhancing appearance of lesion, positive tuberculin skin test along with endemic spread of TB in Pakistan,¹ increased the clinical suspicion for tuberculoma over a neoplastic etiology. Lumbar puncture was not performed as the child had no meningeal symptoms (no neck stiffness, vomiting, bulging fontanelle, or altered consciousness).

After multidisciplinary discussion with neurosurgery and paediatrics team, the case was managed conservatively because the deep thalamic lesion, extending into the midbrain, made surgical biopsy high-risk with expected significant neurological morbidity; accordingly, the patient was treated with anti-tuberculous therapy and adjunctive corticosteroids, along with physiotherapy and rehabilitation. Anti-tuberculous drugs were isoniazid (100mg), Rifampicin (150mg), ethambutol (200mg) and pyrazinamide (300mg) along with steroid prednisolone. Prednisolone was tapered off after 6 weeks. 4 drug tuberculous regime was changed to 2 drugs ie Isoniazid and rifampicin after 2 months with regular follow ups. The doses were adjusted according to the weight of child.

On follow up at 02 months, child weighed 11 kg and was walking independently without support. MRI examination of the brain (Figure 5) showed the clustered ring-enhancing lesions in the right thalamus measuring ∼ 1.5 × 1.35 × 1.3 cm, extending toward the internal capsule, with surrounding mild vasogenic edema, a mild mass effect on the third ventricle, and minimal dilation of the lateral ventricles. Sagittal imaging confirmed interval reduction in the superior–inferior extension of the lesion (Figure 6). Compared to the last MRI, lesion size, edema, and mass effect were reduced, reflecting interval regression of the disease process. There were no sign of diffusion restriction, intracranial hemorrhage, or extra-axial fluid collection, and everything else was as expected: the posterior fossa structures and optic pathways were within normal range. These findings indicated a favourable radiologic response to ongoing anti-tuberculous therapy and adjunctive corticosteroid treatment, supporting conservative medical management with continued clinical and radiologic follow-up.

Figure 5.

Follow-up axial MRI of the brain at 2 months after initiation of antituberculous therapy, showing interval reduction in the size of the clustered ring-enhancing right thalamic lesion, with decreased surrounding vasogenic edema and diminished mass effect on the third ventricle compared with the baseline study (Figure 2).

Figure 6.

Follow-up sagittal MRI at 2 months demonstrating interval regression of the right thalamic lesion, with reduced superior–inferior extension toward the midbrain compared with the initial sagittal imaging (Figure 3).

Discussion

This case presents an unusual form of intracranial tuberculoma, manifesting primarily as an isolated gait disturbance without systemic or meningeal features. Thus, although CNS tuberculosis is well established in the pediatric age, atypical focal manifestations are challenging for diagnosis and can mimic neoplastic or other infectious etiologies.¹⁰ Intracranial tuberculomas arise through hematogenous spread of Mycobacterium tuberculosis, leading to granuloma formation within the brain parenchyma. Deep gray matter involvement, particularly in the thalamus, is less common but clinically important, as even small lesions in this region can disrupt corticospinal and cerebellothalamic pathways, resulting in motor impairment and gait abnormalities.^11,12 Tuberculomas can be caseating or non-caseating. Caseating granulomas typically show a hypointense core on T2-weighted imaging with rim enhancement on post-contrast T1-weighted sequences, whereas non-caseating lesions are often hypointense on both T1- and T2-weighted images with homogeneous enhancement.¹³ Our patient’s MRI revealed several ring-enhancing lesions in the right thalamus and surrounding internal capsule, along with mild surrounding vasogenic oedema and minimal hydrocephalus from the mass effect on the third ventricle. These findings were consistent with intracranial tuberculoma, and subsequent imaging revealed interval regression. Our findings were comparable to a case report of an 11-year-old Pakistani girl with symptoms of hemiparesis and dystonia.¹⁴ Her MRI revealed a single irregular lesion in thalamic region with mild vasogenic edema. Unlike our case, biopsy was performed which confirmed tuberculoma instead of neoplastic etiology.¹⁴ Similar findings were observed in a case series that included a 3-year-old Chinese girl with hemiparesis and headache complaints. On MRI, multiple ring-enhancing lesions surrounded by vasogenic edema in cerebellar and thalamic region were observed. This was followed by surgical excision of cerebellar lesion whereas thalamic lesion was spared due to deep location.¹⁵ As in our case the lesion decreased in size following ATT drug regimen.¹⁵ In very young children, small deficit might be the sole presenting feature, making early detection that much more cinllenging. Radiologically, ring-enhancing lesions in endemic populations should be considered in the differential diagnosis of tuberculoma. MRI findings have high diagnostic specificity when combined with MR spectroscopy, particularly when lipid/lactate peaks are present.^16,17 Microbiological confirmation is frequently absent in parenchymal disease; however, in many cases, only clinicoradiological correlation can demonstrate disease progression, and much of this assessment depends on the therapeutic response.^18,19 The lack of pulmonary or systemic tuberculosis in our patient is consistent with previous reports in pediatric series that neurotuberculosis may develop in the absence of active extracranial disease.²⁰ This highlights the need for a careful exposure history and continued clinical suspicion when initial laboratory findings and chest imaging are unremarkable. In cases such as deep-seated lesions, medical management remains the gold standard. Radiological resolution was demonstrated in most patients treated with standard ATT combined with adjunctive corticosteroids; surgical treatment is appropriate in cases of diagnostic uncertainty, obstructive hydrocephalus, or life-threatening mass effect.²¹ Transient enlargement during treatment, sometimes referred to as a paradoxical reaction, is not uncommon and, provided the clinical picture remains stable, should not be mistaken for treatment failure.²² Early physiotherapy and neurorehabilitation are especially important in toddlers, whose neuroplasticity may lead to remarkable recovery of motor function. Close clinical and radiological follow-up is important for assessing treatment response and preventing long-term neurological sequelae. Overall, even in the absence of systemic or meningeal symptoms, this case emphasises the significance of taking cerebral tuberculoma into account when making a differential diagnosis of isolated paediatric neurological impairments, especially in areas where tuberculosis is endemic.

Conclusion

This case presents with an atypical presentation of intracranial tuberculoma presenting as isolated gait disturbance and mild hemiparesis in a young child without systemic or meningeal features of tuberculosis. In areas endemic for tuberculosis, intracranial tuberculoma should remain as a differential diagnosis even without pulmonary disease or constitutional symptoms. Careful clinical assessment supported by neuroimaging, can aid and guide diagnostic evaluation. Initiating antituberculous therapy with adjunctive corticosteroids soon after presentation will contribute to a full neurological recovery and preventing long-term sequelae. This case illustrates the need to maintain a high clinical suspicion with imaging and appropriate microbiological evaluation rather than depending on advanced imaging.

Funding Statement

The authors received no specific funding for this work.

Abbreviations

CNS, Central nervous system; TB, Tuberculosis; BCG, Bacillus Calmette–Guérin; ATT, Anti-tuberculous therapy; MRI, Magnetic resonance imaging; MR, Magnetic resonance; CBC, Complete blood count; ESR, Erythrocyte sedimentation rate; FOC, Fronto-occipital circumference; CT, Computed tomography; bpm, Beats per minute; cm, Centimeter; ppm, Parts per million.

Data Sharing Statement

All data generated or analyzed during this case report are included in this published article.

Ethics Approval and Consent to Participate

The study was approved by the Ethics Committee of PNS Shifa Hospital Karachi, Pakistan. Institutional approval for publication of the case report was obtained from the Ethics Committee of PNS Shifa Hospital, Karachi, Pakistan. Informed consent to participate was obtained from all participants included in the study and patient’s parent.

Consent for Publication

Written informed consent was obtained from the patient’s parent for publication of the case details and accompanying images.

Author Contributions

KY (Khadija Yasmin): Conception and design of the work, supervision, critical revision for important intellectual content, and final approval of the version to be published. MA (Muhammad Abdullah): Substantial contribution to literature review and drafting of the manuscript, critical revision, and final approval. SS (Sana Shaikh): Contribution to literature search, drafting assistance, manuscript revision, and final approval. MZ (Minahil Zaheer): Interpretation of clinical aspects, critical manuscript review, and final approval. AI (Aleena Ihtasham): Language editing, proofreading, manuscript refinement, and final approval. HHS (Hamna Hassan Siddiqui): Contribution to referencing, manuscript review, and final approval. SS (Saira Shamim): Intellectual input, critical revision of the manuscript, and final approval. HHS (Hudaifa Hassan Salad): Supervision, Contribution to manuscript revision, academic input, and final approval. All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

This paper has been uploaded to Researchsquare as a preprint: https://www.researchsquare.com/article/rs-9124856/v1. The authors declare no competing interests.