MND-POST POLIO SYNDROME (PPS) PATHOLOGY

SUMMARY

1. Polio is transmitted orally, replicating in lymphoid tissue of the pharynx & intestine and subsequently spreading haematologically to anterior horn cells.

2. This results in destruction of the motor neurons, Wallerian degeneration and denervation of muscle fibres.

3. 28-64% develop PPS.

4. Death of remaining motor nerve cells due to ageing & increasing metabolic demands leads to worsening weakness.

5. Each cell is then responsible for activation more motor units than normal.

6. More likely to have weakness and severe problems (breathing) with older onset (> 35 yrs).

Reference(s)

Wilkinson, I., Furmedge, D. and Sinharay, R. (2017). Oxford handbook of clinical medicine. Oxford: Oxford University Press. Get it on Amazon.
Feather, A., Randall, D. and Waterhouse, M. (2020). Kumar And Clark’s Clinical Medicine. 10th ed. S.L.: Elsevier Health Sciences. Get it on Amazon.
Hannaman, R. A., Bullock, L., Hatchell, C. A., & Yoffe, M. (2016). Internal medicine review core curriculum, 2017-2018. CO Springs, CO: MedStudy.
Therapeutic Guidelines. Melbourne: Therapeutic Guidelines Limited. https://www.tg.org.au [Accessed 2021].