Affiliations: Department of Neurology, Sir Ganga Ram Hospital, New
Delhi, India | Department of Neurology, NYP-Weill Cornell Medical
Center, New York, NY, USA | Department of Neurology, Saint Vincent's Hospital and
Medical Centers, New York, NY, USA | Department of Medicine, Saint Vincent's Hospital and
Medical Centers, Staten Island, NY USA
Note: [] Correspondence: Nitin K. Sethi, MD, Department of Neurology,
NYP-Weill Cornell Medical Center, 525 East, 68th Street, New York, NY 10021
USA. Tel.: +1 646 515 5168; Fax: +1 212 746 8845; E-mail:
[email protected]
Abstract: Spinal muscular atrophy (SMA) is a group of allelic autosomal
recessive genetic disorders characterized by progressive motor neuron loss,
symmetrical weakness, and skeletal muscle atrophy. It is traditionally
classified as a pure lower motor neuron disorder, for which currently
definitive diagnosis is possible by molecular genetic testing. The problem
arises when an infant presents clinically like SMA but is negative for survival
motor neuron gene. A 3-month-old infant presented with paucity of limb movement
and weak cry. Clinical presentation was suggestive of spinal muscular atrophy
type I but genetic test for exon 7 deletion on survival motor neuron gene on
chromosome 5 was negative. Detailed investigation revealed this a case of
infantile motor axonal neuropathy. Two years follow-up has revealed partial
recovery in limb movements and of bulbar function. There is paucity in
neurology literature of such cases and the importance of genetic studies is
hence emphasized.
