A comparative study of the conduction velocity of motor and sensory fibres of ulnar and median nerves among leprosy patients and normal subjects
Keywords:Leprosy, Latency 1, Latency 2, Nerve Conduction Velocity, Neuropathy, Sensory nerve conduction velocity
Background: Leprosy and the associated scourge have affected humanity for thousands of years. One of the most debilitating consequences of leprosy is peripheral neuropathy. Nerve Conduction Velocity study provides us with a non-invasive modality to assess peripheral nerve involvement in leprosy.
Methods: With this in mind, a cross-sectional observational study was conducted including 30 leprosy patients as "Cases" and 30 age-matched healthy subjects, not suffering from any kind of neurological disorders, as "Controls". Using a digital electromyography machine, the Latency, Amplitude and Conduction Velocities of Motor and Sensory fibres of Ulnar and Median nerves were recorded. The results were compared among controls and cases using suitable statistical tests (descriptive statistics and significance testing using unpaired t-test).
Results: In this study, with regard to Sensory Nerve conduction Velocity (SNCV), statistically very significant difference was noted in case of right (p 0.0011) and left (p 0.0037) ulnar nerves among controls and cases. The difference in the amplitude of Motor Action potential (MAP) with regard to right median nerve, among cases and controls, was also statistically significant (p 0.0127). Further the amplitude of Sensory Nerve Action Potential (SNAP) values were higher among cases compared to controls.
Conclusions: As such, the findings of this study (and which is also corroborated by many previous studies) lead us to the conclusion that NCV studies can detect lepromatous neuropathy much before the emergence of frank clinical signs and this type of neuropathy is predominantly demyelinating in nature with occasional axonal loss.
Job CK, Jayakumar J, Kearney M, Gillis TP. Transmission of leprosy: A study of skin and nasal secretions of household contacts of leprosy patients using PCR. Am J Trop Med Hyg. 2008 Mar 1;78(3):518-21.
Lastória JC, de Abreu MAMM. Leprosy: Review of the epidemiological, clinical, and etiopathogenic aspects - Part 1. An Bras Dermatol. 2014;89(2):205-18.
Rodrigues LC, Kerr-Pontes LRS, Frietas MVC, Barreto ML. Long lasting BCG protection against leprosy. Vaccine. 2007 Sep 28;25(39-40):6842-4.
Scollard DM. Classification of leprosy: a full color spectrum, or black and white? Int J Lepr Other Mycobact Dis. 2004 Jun;72(2):166-8.
Lepers to get grant for undergoing reconstructive surgery | India News - Times of India. Available at: https://timesofindia.indiatimes.com/india/Lepers-to-get-grant-for-undergoing-reconstructive-surgery/articleshow/4048862.cms. Accessed 18 March 2020.
ILA T. Report of the International Leprosy Association Technical Forum. Paris, France, 22–28 February 2002. Int J Leprosy Other Mycobact Dis. 2002;70(1).
Suzuki K, Akama T, Kawashima A, Yoshihara A, Yotsu RR, Ishii N. Current status of leprosy: epidemiology, basic science and clinical perspectives. J Dermatol. 2012 Feb;39(2):121-9.
Brett-Crowther M. Leprosy and Stigma in the South Pacific: A Region-by-Region History with First Person Accounts. Int J Environ Stud. 2012 Jun;69(3):553-5.
Misra UK, Kalita J. Clinical neurophysiology: nerve conduction, electromyography, evoked potentials. Elsevier Health Sciences; 2019 Dec 26.
Ooi WW, Srinivasan J. Leprosy and the peripheral nervous system: basic and clinical aspects. Muscle Nerve. 2004;30(4):393-409.
Nicholls PG, Croft RP, SMITH W. Delay in presentation, an indicator for nerve function status at registration and for treatment outcomeÐthe experience of the Bangladesh Acute Nerve Damage Study cohort. Lepr Rev. 2003;74:349ą356.
Hawkes CH, Doty RL. Neurodegenerative Chemosensory Disorders. In: Smell and Taste Disorders. Cambridge University Press; 2018: 293-386.
Peripheral neuropathy | Psychology Wiki | Fandom. Available at: https://psychology.wikia.org/wiki/Peripheral_neuropathy. Accessed 29 March 2020.
Werneck LC, Teive HAG, Scola RH. Muscle involvement in leprosy: Study of the anterior tibial muscle in 40 patients. Arq Neuropsiquiatr. 1999;57(3 B):723-34.
Brasil-Neto JP. Electrophysiologic studies in leprosy. Arqu Neuro-psiquiat. 1992 Sep;50(3):313-8.
Van Brakel WH, Nicholls PG, Wilder-Smith EP, Das L, Barkataki P, Lockwood DN, INFIR Study Group. Early diagnosis of neuropathy in leprosy-comparing diagnostic tests in a large prospective study (the INFIR cohort study). PLoS Neglect Tropi Dis. 2008 Apr;2(4):e212.
Vashisht D, Das A, Vaishampayan S, Vashisht S, Joshi R. Nerve conduction studies in early tuberculoid leprosy. Indian Dermatol Online J. 2014;5(6):71.
Scollard D, Joyce MP, Gillis TP. Development of leprosy and type 1 leprosy reactions after treatment with infliximab: a report of 2 cases. Clini Infect Dis. 2006 Jul 15;43(2):e19-22.
Human Polymorphisms as Clinical Predictors in Leprosy. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3246779/. Accessed 18 March 2020.
Husain S, Malaviya GN. Early nerve damage in leprosy: an electrophysiological study of ulnar and median nerves in patients with and without clinical neural deficits. Neurol Ind. 2007 Jan 1;55(1):22.
Cabalar M, Yayla V, Ulutas S, Senadim S, Oktar AC. The clinical & neurophysiological study of leprosy. Pak J Medi Scie. 2014 May;30(3):501.
Scollard DM, Truman RW, Ebenezer GJ. Mechanisms of nerve injury in leprosy. Clin Dermatol. 2020 Mar 31;33(1):46-54.
Serrano-Coll H, Salazar-Peláez L, Acevedo-Saenz L, Cardona-Castro N. Mycobacterium leprae-induced nerve damage: direct and indirect mechanisms. Pathog Dis. 2018 Aug;76(6):fty062.
Xavier MB, do Nascimento MG, Batista KD, Somensi DN, Neto FO, Carneiro TX, et al. Peripheral nerve abnormality in HIV leprosy patients. PLoS Neglect Trop Dis. 2018 Jul 18;12(7):e0006633.
Weinstein DE. Mycobacterium leprae and neuropathies. Trends Microbiol. 2000 Apr;8(4):156-7.
Granger CV. Nerve conduction and correlative clinical studies in a patient with tuberculoid leprosy. Am J Physi Medi Rehabilit. 1966 Oct 1;45(5):244-50.
Kumar A, Girdhar A, Girdhar BK. Nerve thickening in leprosy patients and risk of paralytic deformities: a field based study in Agra, India. Europe PMC. 2004 June 01;75(2): 135-142.
Handbook of Peripheral Neuropathy - PDF Free Download. Available at: https://epdf.pub/handbook-of-peripheral-neuropathy.html. Accessed 31 March 2020.
Hackett ER, Shipley DE, Livengood R. Motor nerve conduction velocity studies of the ulnar nerve in patients with leprosy. Int J Lepr. 1968;36(3):282-7.
Rosenberg RN, Lovelace RE. Mononeuritis multiplex in lepromatous leprosy. Arch Neurol. 1968 Sep 1;19(3):310-4.
Rosenberg NR, Faber WR, Vermeulen M. Unexplained delayed nerve impairment in leprosy after treatment. Lepr Rev. 2003 Dec;74(4):357-65.
Kar S, Krishnan A, Singh N, Singh R, Pawar S. Nerve damage in leprosy: An electrophysiological evaluation of ulnar and median nerves in patients with clinical neural deficits: A pilot study. Ind Dermatol Online J. 2013;4(2):97.
Mallipeddi S, Jasti DB, Apparao A, Vengamma B, Sivakumar V, Kolli S. A clinical and electrophysiological study of peripheral neuropathies in peritoneal dialysis patients: Our experience from rural South India. Saudi J Kidney Dis Transpl. 2018 Sep 1;29(5):1139-49.
Van Brakel WH. Peripheral neuropathy in leprosy and its consequences. Lepr Rev. 2000 Dec 1;71(Suppl):S146-53.