neuro

Question 1

27 M 2mnth hx tingling hands and feet progressed to waist no pain bladder bowel sexual function normal unsteady walking since one week normal obs and examination normal (abdo respiratory cardio, CNS) tone and bulk normal power reduced at wrists, hip and ankles absent left biceps and supinator jerks brisk knee jerks, ankle jerks need reinforcement plantars downing pinprick - impaired to knees and MCPs cold sensation normal vibration sensation reduced to sternum reduced proprioception writhing movements of hands steppage gait - foot drop where is the lesion

Answer 1

tone normal power decreased majority of reflexes reduced therefore: LMN, neuromuscular or muscular sensory problems (due to pinprick impaired, vibration sensation reduced) therefore not muscular problem or neuromuscular problem –> LMN lesion (peripheral neuropathy)

Question 2

motor & sensory neuropathy patchy length dependent (affects longer neurones first painless CNS rapid onset cranial nerves not affected plasma viscosity low ANA, ANCA negative TFT normal lumpar puncture negative folate and ferritin normal vitamin B12 low methylmalonic acid and homocysteine increased diagnosis

Answer 2

B12 deficiency peripheral neuropathy management: replace B12

Question 3

causes of B12 deficiency

Answer 3

IBD (absorbed in antiintrinsic factor low meat intake nitrous oxide (laughing gas) can inactivate B12

Question 4

determining lesions based on tone, power and reflexes

Answer 4

UMN: spasicity (increased tone, decreased power)

LMN, neuromuscular, muscular: decreased tone, decreased power

if sensory impairment then LMN