Motor neuron disease (MND) is neurodegenerative disorder involving primarily motor neurons of cerebral cortex, brainstem, and spinal cord. MND is characterized by the gradual death of upper and lower motor neurons leads to loss of motor function and clinical syndrome of muscle weakness, wasting, and paralysis resulting in death typically within 2–3 years [1-3].

Briefly, the presentations include amyotrophic lateral sclerosis (ALS), in which both the lower motor neurons and upper motor neurons are affected. It is frequently referred to as “Lou Gehrig's disease” in memory of the famous baseball player who died of ALS in 1941 [4]. Other forms primary lateral sclerosis, which is less common than other presentation with only upper motor neuron involvement; and progressive muscular atrophy, with only lower motor neuron signs. Population-based studies have established that the incidence of ALS in Europe is fairly uniform at 2.16/100,000 person-years [5]. Monomelic forms of MND are prevalent in some geographical areas [6].

Himachal Pradesh is located between 30“22’ and 30”12’ north latitude and between 75“47’ and 79”4’ east longitude. It is a mountainous state in northern India, situated in Western part of outer Himalaya in with altitudes ranging from 350 to 7000 meters above mean sea level. It is one of the least urbanized states in India, with predominantly agricultural economy. The lifestyle of population in the area differs from those living in plains. The contemporary data of clinical profile in patients of ALS are limited despite being disabling nature of disease, and also data profile of ALS patients from this region is not available. Here we are presenting a case of female who presented to us with motor neuron disease with monomelic amyotrophy with bulbar onset. This is an extremely rare presentation and only few case reports are there [7].

A 47-year-old female presented in outpatient clinic with a history of weakness of right arm with slurring of speech for one year. There was no history of loose stool, fever, abdominal pain, seizures. There was no history of diabetes mellitus, hypertension and anti-tubercular treatment (ATT) intake in the past. On examination, her blood pressure was 110/70mmHg. Her pulse rate was 87 per minute. Neurological examination was suggestive-higher mental functions and cranial nerves were within normal limit. Her power in right upper limb was 2/5 and lower limbs was 5/5. Her DTR in right upper limb were 3plus.There was atrophy of the muscles of the right arm and hand muscles involved and fasciculations were present. There was no atrophy of muscles in the other limbs.

Her baseline blood investigations were normal. Hemoglobin 12.3 g/dl p/s NCNC TLC 12.6thous/µl, Alkaline phosphatase 129µ/l, Platelets 303thous/µl. Sodium 145mmol/l, Potassium 3mmol/l, Urea 35mg/dl Chloride 114.50mmol/l Creatinine 0.6 mg/dl Protein total 6g/dl Bilirubin 0.21 mg/dl Albumin 2.4g/dl SGOT 33.9µ/l SGPT 24.5 µ/l. Diagnosis of amyotrophic lateral sclerosis according to El Escorial revised criteria [8].

Table 1: Diagnostic certainty based on revised EL Escorial Criteria^a,b,c

Here we reported a woman with amyotrophic lateral sclerosis followed. The diagnosis of ALS was made based on history of weakness of one limb, exaggerated DTR, normal higher mental functions, normal cranial nerves examination and normal sensory examination. We diagnosed our patient according to EL Escorial revised criteria-definite ALS-UMN and LMN signs in three regions Table 1.

                
Bulbar onset is more common in elderly (age >60 years) females and females have worse prognosis than males [7]. 25% of patients with ALS have the bulbar onset [9].

Motor neuron diseases is a neurodegenerative disease. Monomelic amyotrophy with bulbar onset is a rare presentation with amyotrophic lateral sclerosis as reported in the case.

Declaration of Patient Consent: The authors certify that they have obtained all appropriate consent forms. The patient understands that name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. 

Conflict of Interest

Nil

Source of Support and Sponsorships

Nil

1. Davenport, R.J. et al. “Avoiding false positive diagnoses of motor neuron disease: Lessons from the scottish motor neuron disease register.” Journal of Neurology, Neurosurgery & Psychiatry, vol. 60, no. 2, 1996, pp. 147–51.

2. Chad, D.A. and E.P. Pioro. Amyotrophic Lateral Sclerosis. Contemporary Neurology Series, Oxford University Press, 1998.

3. Norris, F. et al. “Onset, natural history and outcome in idiopathic adult motor neuron disease.” Journal of the Neurological Sciences, vol. 118, no. 1, 1993, pp. 48–55.

4. Rowland, L.P. “Ten central themes in a decade of als research.” Advances in Neurology, vol. 56, 1991, pp. 3–23.

5. Kiernan, M.C. et al. “Amyotrophic lateral sclerosis.” The Lancet, vol. 377, no. 9769, 2011, pp. 942–55.

6. Shaw, P.J. and C. Wood-Allum. “Motor Neurone disease: A practical update on diagnosis and management.” Clinical Medicine, vol. 10, no. 3, 2010, pp. 252.

7. Sondhi, S. et al. “The profile of amyotrophic lateral sclerosis in natives of western himalayas: Hospital-based cohort study.” Journal of Neurosciences in Rural Practice, vol. 9, no. 3, 2018, pp. 305–11.

8. Brooks, B.R. et al. “El escorial revisited: Revised criteria for the diagnosis of amyotrophic lateral sclerosis.” Amyotrophic Lateral Sclerosis and Other Motor Neuron Disorders, vol. 1, no. 5, 2000, pp. 293–99.

9. Preston, David C. “Amyotrophic lateral sclerosis and its variants.” Electromyography and Neuromuscular Disorders, 2021.