Give the most probable diagnosis of a 1 yr. old child normal intelligence with features of hypotonia. On exanimation there are tongue fasciculations and he keeps his body in a frog like position – (AIIMS Nov 2014)
|A||Guillian Barre Syndrome|
|B||Limb girdle atrophy|
|D||Spinal muscular atrophy|
Spinal muscular atrophy
o Features of hypotonia and frog like position suggest the diagnosis of Floppy infant syndrome.
Floppy infant syndrome
o In FIS the baby is floppy i.e:
• He cannot hold his head up, there will be marked head lag as the baby is pulled up from supine to sitting posture.
• A normal infant, on ventral suspension ( supporting the infant with a hand under the chest) keeps his back straight and head slightly up, arms abducted and knees partly flexed. A floppy infant droops, over the hand like an inverted (J.
• Hypotonia and decreased muscular activity
• Frog like posture or other unusual position at rest
• Delay in motor milestone
Causes of Floppy syndrome
1. Central nervous system
Perinatal asphyxia, neonatal encephalopathy, kernicterus, cerebral plasy (atonic type) intracranial hemorrhage, chromosomal anomalies including
Down syndrome and inborn errors of metabolism e.g. aminoacidurias, Mucopolysaccharidosis, and cerebral lipidosis.
2. Spinal cord lesions
Anterior horn cell disease: Werdnig Hoffman spinal muscular atrophy, poliomyelitis
3. Peripheral nerves
Acute polyneuropathy, familial dysautonomia, congenital sensory neuropathy
4. Myoneural junction
Neonatal myasthenia gravis, infantile botulism, following antibiotic therapy
Muscular dystrophies, congenital myotonic dystrophies, congenital, myopathies (including central core disease and Nemaline myopathy), polymyositis, glycogen
Storage disease (Pomp’s), and arthrogryposis multiplex congenital
Protein energy malnutrition, rickets, Prader-Willi syndrome, malabsorption Syndromes, Ehler-Danlos syndrome, cutis laxa, cretinism
Coming back to question
o There are many causes of floppy infant syndrome.
o Out of the four option given in the question three of these can cause FIS -
• Downs syndrome
• GB. syndrome
• Spinal muscular atrophy
o Spinal muscular atrophy
• Features of normal intelligence and tongue fasciculations strongly suggest spinal muscular atrophy.
o Down's syndrome
• Can be easily ruled out as intelligence is impaired in Down's syndrome.
o GB. syndrome
• Can be ruled out as it presents as an acute case with a past history off ever or viral infections.
Majority of patients recover within few days to 2 weeks-