Diagnostic Difficulties in Childhood Bilateral Thalamic Astrocytomas

Abstract

We report on two children with bilateral thalamic astrocytomas. The first patient developed psychomotor regression at the age of 20 months followed by rapidly progressive ataxia, intention tremor, slurred speech, and bouts of drowsiness. Magnetic resonance imaging (MRI) of the brain showed swelling and high signal intensity in both thalami accompanied by supratentorial hydrocephalus. The second patient presented with progressive cerebellar ataxia, headache, and vomiting at the age of 11 years. MRI of the brain revealed symmetrical, hyperintense and sharply delineated swelling of both thalami. Additional lesions were seen in the cerebellum and the right temporal lobe. In both cases proton magnetic resonance spectroscopy (MRS) of the lesions showed a striking decrease of the neuronal marker N-acetylaspartate, an increase of choline-containing compounds, and a minimal lactate peak. Stereotactic biopsies from the thalamus of the first patient and from a cerebellar lesion of the second patient finally revealed glial tumors, namely a diffuse astrocytoma of World Health Organization (WHO) grade II in the first patient and an anaplastic astrocytoma of WHO grade III in the second patient. We conclude that the clinical manifestations and MRI patterns of bilateral thalamic astrocytomas are very similar to those of encephalitis and neurometabolic disorders and should therefore be included in the differential diagnosis of these encephalopathies.

Bithalamic Astrocytoma - Encephalitis - Leigh Syndrome - Organic Acidopathies - Magnetic Resonance Imaging - Proton Magnetic Resonance Spectroscopy

References

• 1 Allen J C. Initial management of children with hypothalamic and thalamic tumors and the modifying role of neurofibromatosis-1.  Pediatr Neurosurg. 2000;  32 154-162
• 2 Arii J, Tanabe Y. Leigh sndrome: Serial MR imaging and clinical follow-up.  Am J Neuroradiol. 2000;  21 1502-1509
• 3 Bernstein M, Hoffman H, Halliday W, Hendrick E, Humphreys R. Thalamic tumors in children.  J Neurosurg. 1984;  61 649-656
• 4 Burger P C, Cohen J C, Rosenblum M K, Tihan T. Pathology of diencephalic astrocytomas.  Pediatr Neurosurg. 2000;  32 214-219
• 5 Estève F, Grand S, Rubin C, Hoffmann D, Pasquier B, Graveron-Demilly D. et al . MR spectroscopy of bilateral thalamic gliomas.  Am J Neuroradiol. 1999;  20 876-881
• 6 Kleihues P, Cavenee W K. Pathology and Genetics of Tumors of the nervous system. World Health Organization Classification of Tumors. Lyon; IARC Press 2000: 9-54
• 7 Kölker S, Mayatepek E, Hoffmann G F. White matter disease in cerebral organic acid disorders: clinical implications and suggested pathomechanisms.  Neuropediatrics. 2002;  33 225-231
• 8 Mizuguchi M, Abe J, Mikkaichi K, Noma S, Yoshida K, Yamanaka T. et al . Acute necrotizing encephalopathy of childhood: a new syndrome presenting with multifocal, symmetric brain lesions.  J Neurol Neurosurg Psychiatry. 1995;  58 555-561
• 9 Munoz A, Mateos F, Simón R, García-Silva M T, Cabello S, Arenas J. Mitochondrial diseases in children: neuroradiological and clinical features in 17 patients.  Neuroradiol. 1999;  41 920-928
• 10 Murphy S N, Faden H S, Cohen M E, Bakshi R. Acute disseminated encephalomyelitis in children.  Pediatrics. 2002;  110 in press
• 11 Partlow G, Carpio-O'Donovan R, Melanson D, Peters T. Bilateral thalamic gliomas: Review of eight cases with personality change and mental deterioration.  Am J Neuroradiol. 1992;  13 1225-1230
• 12 Reardon D A, Gajjar A, Sanford R A, Heideman R L, Walter A W, Thompson S J. et al . Bithalamic involvement predicts poor outcome among children with thalamic glial tumours.  Pediatr Neurosurg. 1998;  29 29-35
• 13 Russell D S, Rubinstein L J. Pathology of Tumors of the Nervous System. 5th ed. London; Arnold 1989: 123-138
• 14 Savasta S, Comi G P, Perini M P, Lupi A, Strazzer S, Rognoni F, Rossoni R. Leigh disease: clinical, neuroradiologic, and biochemical study of three new cases with cytochrome c oxidase deficiency.  J Child Neurol. 2001;  16 608-613
• 15 Savoiardo M, Zeviani M, Uziel G, Farina L. MRI in Leigh syndrome with SURF1 gene mutation.  Ann Neurol. 2002;  5 138-149
• 16 Stiller C A, Nectoux J. International incidence of childhood brain and spinal tumours.  Int J Epidemiol. 1994;  23 458-464
• 17 Takahashi S, Oki J, Miyamoto A, Okuno A. Proton magnetic resonance spectroscopy to study the metabolic changes in the brain of a patient with Leigh syndrome.  Brain Develop. 1999;  21 200-204
• 18 Valanne L, Ketonen L, Majander A, Suomalainen A, Pihko H. Neuroradiologic findings in children with mitochondrial disorders.  Am J Neuroradiol. 1998;  19 369-377
• 19 van der Knaap M S, Valk (Eds) J. Magnetic Resonance of Myelin, Myelination, and Myelin Disorders. Berlin, Heidelberg, New York; Springer-Verlag 1995 53-64 106-164
• 20 Yoshida M, Fushiki S, Takeuchi Y, Takanashi M, Imamura T, Shikata T. et al . Diffuse bilateral thalamic astrocytomas as examined serially by MRI.  Childs Nerv Syst. 1998;  14 384-388