Pediatric spinal nerve root enhancement: Clinical and differential considerations

1. eEdE-200-6875 Pediatric spinal nerve root enhancement: Clinical and differential considerations Marinos Kontzialis1, Hans Michell2, Andrea Poretti2, Thierry A.G.M. Huisman2 1Division of Neuroradiology and 2Pediatric Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA ASNR 53rd Annual Meeting, Chicago, April 25-30, 2015 mkontzi1@jhmi.edu

2. Disclosure • We have nothing to disclose • No relevant financial relations interfering with our presentation

3. Purpose • Case-based review of pediatric nerve root enhancement • Clinical and differential considerations

4. Introduction • Pediatric spinal nerve root enhancement: • Indicates blood-nerve-barrier disruption • Is a nonspecific finding

5. Case 1 2-year-old with ascending weakness A B C Diffuse nerve root enhancement in the cervical (A), thoracic (B) and lumbar spine (C)

6. Guillain-Barré syndrome (GBS) • Autoantibody-mediated acute motor weakness: • Pathogenesis = molecular mimicry and cross reactive immune reaction • Prevalence: 1.2-2.3/100,000 • Usually preceding upper respiratory or GI infection (Campylobacter jejuni) • Maximum weakness within 4 weeks • Progressive weakness > 8 weeks  chronic inflammatory demyelinating polyneuropathy (CIDP) • CSF = albumin-cytological dissociation

7. Guillain-Barré syndrome: MRI • Nerve root enhancement: > 90% • Different patterns of enhancement • Diffuse = 68% • Ventral roots = 27% • Dorsal roots = 5%

8. Guillain-Barré syndrome: MRI • Cranial nerve (CN) involvement = 50% Bilateral CN V enhancement (arrows)

9. Differential diagnosis 1 • Transverse myelitis: • Quicker presentation compared to GBS (hours-few days vs. several days) • Sensory-motor level (not present in GBS) • MRI: spinal cord signal abnormalities + enhancement 10-year-old with transverse myelitis presenting with quadriplegia over 24-48 h

10. Differential diagnosis 2 Guillain-Barré syndrome West-Nile virus radiculitis • Poliomyelitis-like syndrome with acute flaccid paralysis + sensory sparing • MRI: most often normal, but ventral nerve roots enhancement is possible • Can look identical to GBS

11. Case 2 • 8-year-old with congenital HIV infection B A C Bilateral CN III enhancement (A) and diffuse nerve root enhancement and mild thickening (B, C)

12. Chronic inflammatory demyelinating polyneuropathy (CIDP) • Inflammation mediated demyelination • Prevalence: 1-7.7/100,000 • Clinically heterogeneous, grossly symmetric sensory and/or motor neuropathy • Develops over > 8 weeks (GBS < 4 weeks) • No preceding infection • CSF = increased protein, normal cell count  supportive of nerve root inflammation

13. Chronic inflammatory demyelinating polyneuropathy • CIDP may occur in the context of: • Hepatitis C • Inflammatory bowel disease • Monoclonal gammopathy of undetermined significance (MGUS) • HIV/AIDS • Organ transplant • Connective tissue disorders

14. Chronic inflammatory demyelinating polyneuropathy • MRI: enhancement + hypertrophy of root + plexus possible  widespread inflammation • Can mimic neurofibromatosis type 1 16-year-old with thickening and mild enhancement of lumbar plexus (arrowheads) and sacral nerve roots (arrows)

15. Case 3 • 9-month-old from El Salvador with a 2-week Hx of fever, lethargy, and emesis A B C D Diffuse meningeal enhancement in the posterior fossa (B), around the cord (B), and cauda equina nerve roots (D). Minimal clumping of the nerve roots (D).

16. Case 3 A B C Basilar meningitis CN V enhancement CN VI, VII, VIII enhancement + rim enhancing lesion in the right middle cerebellar peduncle

17. Tuberculosis • Most common infectious cause of spinal arachnoiditis (= inflammation of the meninges) • CSF: increased protein, decreased glucose, increased cells (mainly lymphocytes) • Nerve root enhancement = 30%, predominantly smooth

18. Case 4 • 3-year-old with subacute onset of bilateral facial weakness and dysarthria A B C Diffuse nerve root enhancement in the cervical (A), thoracic (B) and lumbar spine (C)

19. Case 4 CN VII + VIII enhancement CN V enhancement CN III enhancement

20. Bannwarth syndrome • Lyme meningo-radiculo-neuritis caused by spirochete Borrelia burgdorferi • Most common tick-borne disease in the US • Geography, recreational habits, season (peak in the summer) are clues! • Confirmed by serum + CSF antibodies • CSF = lymphocytic meningitis • Erythema migrans in 89% of children = facilitates the diagnosis

21. Bannwarth syndrome • MRI: • MS-like periventricular white matter lesions • Cranial nerve enhancement • Nerve root enhancement • In the appropriate geographic + seasonal setting  facial diplegia/palsy = highly suggestive of Lyme disease, especially when coupled with erythema migrans

22. Case 5 • 13-year-old with progressive polyneuropathy Thickening of the cauda equina nerve roots without evidence of enhancement (not shown)

23. Case 5 CN III thickening + enhancement CN V thickening + enhancement CN VII, VIII thickening + enhancement

24. Charcot-Marie-Tooth disease • Hereditary motor + sensory neuropathies • Symmetric + predominately distal motor + sensory disturbances, slowly progressive course • MRI: typically associated with marked thickening of the nerves (hypertrophic neuropathies)

25. Differential diagnoses • Metachromatic leukodystrophy (MLD) + Krabbe disease • Can present with diffuse cranial nerve and cauda equina enhancement • May be simultaneous or precede typical white matter abnormalities  Consider measuring arylsulfatase A + galactocerebrosidase in all children with unexplained cranial nerve and caudal nerve root enhancement MLD Krabbe disease

26. Case 6 • 3-year-old with developmental delay + failure to thrive Diffuse leptomeningeal + subarachnoid enhancement Diffuse thickening of the nerve roots

27. Case 6 Avidly enhancing pineal mass with diffuse leptomeningeal enhancement in the posterior fossa + around the cord Leptomeningeal enhancement coating bilateral CN V

28. Pineoblastoma with leptomeningeal carcinomatosis • Neoplastic causes of nerve root enhancement in the pediatric population: • Medulloblastoma • Germinoma • Pineoblastoma • PNET • Ependymoma • Astrocytoma • Lymphoma • Leukemia

29. Smooth nerve root enhancement • Most common, but least specific CIDP Lyme disease Tuberculosis GBS West Nile virus radiculitis

30. Nerve root enhancement + thickening CMT disease CIDP Leptomeningeal carcinomatosis (enhancement can be nodular)

31. Summarizing table

32. Take-home messages • Pediatric nerve root enhancement = nonspecific • Clinical presentation, imaging findings and CSF testing will point towards the right direction + guide further management mkontzi1@jhmi.edu

33. Suggested literature • Zuccoli G et al. Redefining the Guillain-Barre spectrum in children: neuroimaging findings of cranial nerve involvement. AJNR 2011;32(4):639-42. • Van Doorn PA et al. Clinical features, pathogenesis, and treatment of Guillain-Barre syndrome. Lancet Neurol 2008;7:939-50. • Mulkey SB et al. Nerve root enhancement on spinal MRI in pediatric Guillain-Barre syndrome. Pediatr Neurol 2010;43(4):263-9. • Vallat JM et al. Chronic inflammatory demyelinating polyradiculoneuropathy: diagnostic and therapeutic challenges for a treatable condition. Lancet Neurol 2010;9:402-12. • Sharma A et al. MR imaging of tubercular spinal arachnoiditis. AJR 1997;168(3):807-12. • Hildenbrand P et al. Lyme neuroborreliosis: manifestations of a rapidly emerging zoonosis. AJNR 2009;30:1079-87. • Cellerini M et al. Imaging of the cauda equina in hereditary motor sensory neuropathies: correlation with sural nerve biopsy. AJNR 2000;21:1793-8. • Morana G et al. Enhancing cranial nerves and cauda equina: an emerging magnetic resonance pattern in metachromatic leukodystrophy and Krabbe disease. Neuropediatrics 2009;40:291-4. • Zapadka M. Diffuse cauda equina nerve root enhancement. J Am Osteopath Coll Radiol 2012; Vol. 1, Issue 1.