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Floppy infant / decreased Moro (SMA vs hypothyroid)

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Teaching point — how the wording changes the answer

SMA = hypotonia + areflexia + tongue fasciculations, but ALERT with preserved social smile / eye-following -> confirm with SMN1 molecular genetic testing. Congenital hypothyroidism = hypotonia + drowsy + CONSTIPATION + macroglossia + prolonged jaundice -> TFT. The discriminating words: 'tongue fasciculations / smiles & follows' -> SMA/genetics; 'constipation / macroglossia / drowsy' -> hypothyroid/TFT.

Q25 Infant, decreased Moro, smiles and follows with eyes. Test?
Key clue Smiles/follows = cognition intact -> SMA
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Molecular genetics (SMN1)
Q80 Newborn hypotonia + reduced reflexes + head lag (hypothyroid / SMA / CP)
Key clue Areflexia + head lag
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Spinal muscular atrophy
Q136 10-month, alert, smiling, head lag, decreased LL reflexes. Investigation?
Key clue Alert + areflexia
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Muscle/genetic test
Q140 Hypotonic, reduced Moro. Investigation for diagnosis?
Key clue Repeat stem
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Molecular genetics
Q155 8-week baby, SMA features
Key clue SMA features
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Molecular genetic test
Q156 Older child, SMA features with TONGUE FASCICULATION
Key clue Tongue fasciculation = classic SMA
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Molecular genetic test
Q161 8 weeks, hypotonia + absent reflexes (genetic / TFT / CK)
Key clue Areflexia
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Genetic testing
Q203 10-month, drowsy, CONSTIPATED, reduced activity. Investigation?
Key clue Constipation + drowsy -> hypothyroid (the discriminator)
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TFT
Q247 8-month head lag + decreased limb reflex. Investigation?
Key clue Head lag + areflexia
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Genetic test
Q305/Q306/Q326 SMA diagnostic / confirmatory test (several variants, +/- family hx, gait)
Key clue NCS vs genetic
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Genetic testing (confirmatory)
Q400 Floppy infant + TONGUE FASCICULATIONS
Key clue Tongue fasciculations
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Spinal muscular atrophy
Q439 Infant decreased Moro, NO tongue fasciculations (TFT / genetic test)
Key clue No fasciculations -> consider hypothyroid too, but still genetic for SMA
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Genetic test
Q481 SMA diagnosis
Key clue Standard
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Genetic testing
NA-1 Child smiles, diminished reflex, NO macroglossia or constipation. Investigation?
Key clue No macroglossia/constipation rules out hypothyroid -> SMA
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Genetic study