Acute Motor Axonal Neuropathy
Introduction[edit | edit source]
Acute motor axonal neuropathy (AMAN) is classified as a subtype of Guillain–Barré syndrome (GBS)[1]. The disease was first discovered in China and was nicknamed 'chinese paralytic disease'[1]. AMAN is the most common cause of flaccid paralysis in China[2]. Pathology in AMAN patients are usually limited to the motor nerve, with macrophages destroying axons while myelin remains intact, a contrast to AIDP GBS (most common form of GBS) which is known as a demyelinating disease[1]. While AMAN mainly involves axonal damage to motor nerve fibres; acute inflammatory demyelinating polyradiculoneuropathy (AIDP) involves both motor and sensory nerve fibre damage due to demyelination[1].
AMAN has an estimated prevalence of 30–65% in Asia, Central and South America[3].
Aetiology[edit | edit source]
- AMAN is strongly linked to Campylobacter jejuni and Zika virus infection[4][5]
- AMAN has some documented association with hepatitis E infection[6]
Clinical features[edit | edit source]
AMAN presents similarly in terms of clinical features as well as CSF findings to GBS:[1]
- Weakness of limbs (earliest symptom is weakness of lower limbs)
- Weakness of respiratory muscles
- Gradual weakening and finally, absence of tendon reflexes
- Bulbar palsy in 61% of patients[1]
However, it generally presents without any sensory symptoms, unlike AIDP-GBS[6], although it can present with sensory symptoms[7]. A neurophysiological screen in patients with AMAN should also show no evidence of demyelination, unlike GBS[6].
The prevalence of pain can also differ between the subtypes of GBS[8] - many patients with AMAN also experience back and neck pain[9].
Prognosis[edit | edit source]
The prognosis of AMAN is worse compared to the other subtypes of GBS[10][11].
References[edit | edit source]
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Lv J, Zhaori G. Collaborative studies of U.S.–China neurologists on acute motor axonal neuropathy - PMC (nih.gov) Pediatr Investig. 2022 Mar 22;6(1):1-4. doi: 10.1002/ped4.12316. PMID: 35382424; PMCID: PMC8960912.
- ↑ McKhann GM, Cornblath DR, Griffin JW, Ho TW, Li CY, Jiang Z, Wu HS, Zhaori G, Liu Y, Jou LP, Liu TC. Acute motor axonal neuropathy: a frequent cause of acute flaccid paralysis in China. Annals of neurology. 1993 Apr;33(4):333-42.
- ↑ Van den Berg B, Walgaard C, Drenthen J, Fokke C, Jacobs BC, Van Doorn PA. Guillain–Barré syndrome: pathogenesis, diagnosis, treatment and prognosis. Nature Reviews Neurology. 2014 Aug;10(8):469-82.
- ↑ Ho TW, Mishu B, Li CY, Gao CY, Cornblath DR, Griffin JW, Asbury AK, Blaser MJ, McKhann GM. Guillain-Barre syndrome in northern China Relationship to Campylobacter jejuni infection and anti-glycolipid antibodies. Brain. 1995 Jun 1;118(3):597-605.
- ↑ Watrin L, Ghawché F, Larre P, Neau JP, Mathis S, Fournier E. Guillain–Barré syndrome (42 cases) occurring during a Zika virus outbreak in French Polynesia. Medicine. 2016 Apr 1;95(14):e3257.
- ↑ 6.0 6.1 6.2 Al-Saffar A, Al-Fatly B. Acute Motor Axonal Neuropathy in Association with Hepatitis E. Front Neurol. 2018 Feb 9;9:62. doi: 10.3389/fneur.2018.00062. PMID: 29479336; PMCID: PMC5811470.
- ↑ Sekiguchi Y, Uncini A, Yuki N, Misawa S, Notturno F, Nasu S, Kanai K, Noto YI, Fujimaki Y, Shibuya K, Ohmori S. Antiganglioside antibodies are associated with axonal Guillain–Barré syndrome: a Japanese–Italian collaborative study. Journal of Neurology, Neurosurgery & Psychiatry. 2012 Jan 1;83(1):23-8.
- ↑ Ruts L, Drenthen J, Jongen JL, Hop WC, Visser GH, Jacobs BC, Van Doorn PA, Dutch GBS Study Group. Pain in Guillain-Barre syndrome: a long-term follow-up study. Neurology. 2010 Oct 19;75(16):1439-47.
- ↑ McKhann GM, Cornblath DR, Ho T, Griffin JW, Li CY, Bai AY, Wu HS, Yei QF, Zhang WC, Zhaori Z, Jiang Z. Clinical and electrophysiological aspects of acute paralytic disease of children and young adults in northern China. The Lancet. 1991 Sep 7;338(8767):593-7.
- ↑ Zhang Y, Zhao Y, Wang Y. Prognostic factors of Guillain-Barré syndrome: a 111-case retrospective review. Chin Neurosurg J. 2018 Jun 18;4:14. doi: 10.1186/s41016-018-0122-y. PMID: 32922875; PMCID: PMC7398209.
- ↑ Seta T, Nagayama H, Katsura K, Hamamoto M, Araki T, Yokochi M, Utsumi K, Katayama Y. Factors influencing outcome in Guillain-Barré Syndrome: comparison of plasma adsorption against other treatments. Clin Neurol Neurosurg. 2005 Oct;107(6):491-6. doi: 10.1016/j.clineuro.2004.12.019. PMID: 16202823.
