<%server.execute "isdev.asp"%> Neuroradiological findings in maple syrup urine disease Indiran V, Gunaseelan R E - J Pediatr Neurosci
home : about us : ahead of print : current issue : archives search instructions : subscriptionLogin 
Users online: 1181      Small font sizeDefault font sizeIncrease font size Print this page Email this page


 
  Table of Contents    
NEUROIMAGING
Year : 2013  |  Volume : 8  |  Issue : 1  |  Page : 31-33
 

Neuroradiological findings in maple syrup urine disease


1 Department of Radiodiagnosis, Sree Balaji Medical College and Hospital, Chennai, India
2 Department of Radiodiagnosis, Bharat Scans, Chennai, India

Date of Web Publication6-May-2013

Correspondence Address:
Venkatraman Indiran
32, Kumarapuram, Chromepet, Chennai - 600 044, Tamil Nadu
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1817-1745.111419

Rights and Permissions

 

   Abstract 

Maple syrup urine disease is a rare inborn error of amino acid metabolism involving catabolic pathway of the branched-chain amino acids. This disease, if left untreated, may cause damage to the brain and may even cause death. These patients typically present with distinctive maple syrup odour of sweat and urine. Patients typically present with skin and urine smelling like maple syrup. Here we describe a case with relevant magnetic resonance imaging findings and confirmatory biochemical findings.


Keywords: Magnetic resonance imaging, maple syrup urine disease, restricted diffusion


How to cite this article:
Indiran V, Gunaseelan R E. Neuroradiological findings in maple syrup urine disease. J Pediatr Neurosci 2013;8:31-3

How to cite this URL:
Indiran V, Gunaseelan R E. Neuroradiological findings in maple syrup urine disease. J Pediatr Neurosci [serial online] 2013 [cited 2019 Jun 26];8:31-3. Available from: http://www.pediatricneurosciences.com/text.asp?2013/8/1/31/111419



   Introduction Top


Maple syrup urine disease (MSUD) is a metabolic error involving catabolic pathway of the branched-chain amino acids leading to build up of ketoacids, which give rise to the classic 'maple syrup' or burnt sugar smell. MSUD affects an estimated 1 in 185,000 infants worldwide. The most common and severe form of the disease is the classic type, which becomes apparent soon after birth. Beginning in early infancy, this condition is characterized by poor feeding, vomiting, lethargy and developmental delay. If untreated, MSUD can lead to seizures, coma, and death. [1] Here we describe the Magnetic resonance imaging (MRI) findings in classic type of MSUD, which presented without the classic maple syrup smell.


   Case Report Top


A 11-day-old male baby, born of primigravida mother of Indian origin through second degree consanguineous marriage was well for 2 days after birth and then developed marked lethargy, progressing to seizures and coma. Antenatal period was uneventful with a normal vaginal delivery. There was no history of birth asphyxia.

At presentation to the hospital baby was unresponsive to pain except for tonic movements of upper limbs. Markedly boggy anterior fontanelle, usually seen in MSUD, prompted a referral for MRI, though urine and skin showed no typical smell of maple syrup. Cerebrospinal fluid (CSF) analysis was normal.

MRI showed diffuse restricted diffusion involving bilateral cerebellar white matter, entire brain stem, bilateral thalami, internal capsules and corticospinal tracts [Figure 1], [Figure 2] and [Figure 3]. Subtle T2 FLAIR (Fluid Attenuation And Inversion Recovery) hyperintensity is seen in the above regions [Figure 4]. Aminoaciduria was suggested as the possible diagnosis with a suggestion to rule out MSUD.
Figure 1: (a) Axial diffusion weighted images (DWI) image showing restricted diffusion in bilateral middle cerebellar peduncles, (b) Axial DWI image showing restricted diffusion in brainstem, (c) Axial DWI image showing restricted diffusion in corticospinal tracts

Click here to view
Figure 2: (a) Axial apparent diffusion coefficient (ADC) image showing restricted diffusion in bilateral middle cerebellar peduncles, (b) Axial ADC image showing restricted diffusion in brainstem, (c) Axial ADC image showing restricted diffusion in corticospinal tracts

Click here to view
Figure 3: Coronal DWI image showing restricted diffusion in bilateral cerebellar white matter, entire brain stem, bilateral thalami, internal capsules and corticospinal tracts

Click here to view
Figure 4: Axial T2 weighted image showing hyperintense signal change in the pons and bilateral middle cerebellar peduncles

Click here to view


Tandem mass spectroscopy showed increased levels of leucine and isoleucine (=1787 nmol/ml; ref < 350) but normal valine. Urine gas chromatography-mass spectrometry (GC-MS) confirmed MSUD.

The patient was treated with dietary modification and measures to reduce cerebral edema. Unfortunately, the baby expired on day 15 of life, without responding to treatment.


   Discussion Top


Diffusion-weighted magnetic resonance (MR) has an important role in the assessment of brain maturation and of white matter diseases in the fetus, neonate and the child. Diffusion MR imaging enables a better characterization of the lesions demonstrated by conventional MR imaging, for instance, in the hypoxic-ischemic encephalopathy, in infections and in the inherited metabolic diseases, and is particularly important for the longitudinal evaluation of these conditions. [2] The areas of restricted diffusion represent cytotoxic edema and damaged oligodendro-axonal units within the affected white matter. [3] Generalized diffuse edema, though not characteristic is known to occur in MSUD with localized, more severe edema involving the deep cerebellar white matter, the dorsal part of the brainstem, the cerebral peduncles, and the dorsal limb of the internal capsule. [4],[5] Our patient showed diffuse restricted diffusion involving bilateral cerebellar white matter, entire brain stem, bilateral thalami, internal capsules and corticospinal tracts. Presence of such finding points towards aminoacidurias, including MSUD, in spite of the absence of maple syrup odor. Differential diagnoses for similar pattern of restricted diffusion include nonketotic hyperglycinemia and Canavan disease. [6] Lab investigations (tandem mass spectroscopy for blood levels of amino acids and Urine GC-MS for urine levels of amino acids) are confirmatory for the underlying disease. Though MSUD is life threatening as in our case, earlier and prompt treatment of MSUD would help reverse the decompensated state and prevent associated mortality and brain damage in surviving patients. Follow-up MRI can reflect the reversal of findings in appropriately treated cases. [7] Prompt recognition of the pattern of diffuse restricted diffusion involving bilateral cerebellar white matter, entire brain stem, bilateral thalami, internal capsules and corticospinal tracts and raising the suspicion of aminoacidurias, is essential in curtailing the morbidity and mortality of the affected patients.

 
   References Top

1.Naughten ER, Jenkins J, Francis DE, Leonard JV. Outcome of maple syrup urine disease. Arch Dis Child 1982;57:918-21.  Back to cited text no. 1
    
2.Mascalchi M, Filippi M, Floris R, Fonda C, Gasparotti R, Villari N. Diffusion-weighted MR of the brain: Methodology and clinical application. Radiol Med 2005;109:155-97.  Back to cited text no. 2
    
3.Parmar H, Sitoh YY, Ho L. Maple syrup urine disease: Diffusion-weighted and diffusion-tensor magnetic resonance imaging findings. J Comput Assist Tomogr 2004;28:93-7.  Back to cited text no. 3
    
4.Brismar J, Aqeel A, Brismar G, Coates R, Gascon G, Ozand P. Maple syrup urine disease: Findings on CT and MR scans of the brain in 10 infants. AJNR Am J Neuroradiol 1990;11:1219-28.  Back to cited text no. 4
    
5.Jan W, Zimmerman RA, Wang ZJ, Berry GT, Kaplan PB, Kaye EM. MR diffusion imaging and MR spectroscopy of maple syrup urine disease during acute metabolic decompensation. Neuroradiology 2003;45:393-9.  Back to cited text no. 5
    
6.Bindu PS, Kovoor JM, Christopher R. Teaching neuro images: MRI in maple syrup urine disease. Neurology 2010;74:e12.  Back to cited text no. 6
    
7.Sener RN. Maple syrup urine disease: Diffusion MRI, and proton MR spectroscopy findings. Comput Med Imaging Graph 2007;31:106-10.  Back to cited text no. 7
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4]



 

Top
Print this article  Email this article
 
 
  Search
 
  
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Article in PDF (919 KB)
    Citation Manager
    Access Statistics
    Reader Comments
    Email Alert *
    Add to My List *
* Registration required (free)  


    Abstract
   Introduction
   Case Report
   Discussion
    References
    Article Figures

 Article Access Statistics
    Viewed2880    
    Printed54    
    Emailed1    
    PDF Downloaded182    
    Comments [Add]    

Recommend this journal