Neuromuscular Programme

Myasthenia gravis is an autoimmune condition in which the body's immune system produces antibodies that attack the acetylcholine receptors at the neuromuscular junction — the point where nerve signals are transmitted to muscle. This impairs signal transmission, causing the fluctuating, fatigable weakness that is the hallmark of the condition: weakness that is worse with activity and better with rest, most commonly affecting the eyes, face, throat, and limbs. Myasthenia gravis cannot be "cured" in most cases, but it can be effectively controlled in the majority of patients. With appropriate immunosuppressive therapy, most patients achieve minimal manifestation status — essentially normal function with minimal or no symptoms. Thymectomy (removal of the thymus) improves long-term outcomes in patients with generalised MG under age 60 who have been diagnosed within five years.

Guillain-Barré syndrome (GBS) is an acute inflammatory disorder in which the immune system attacks the peripheral nerves, causing rapidly progressive ascending weakness, loss of deep tendon reflexes, and sensory symptoms. It typically develops 2–4 weeks after a respiratory or gastrointestinal infection — most commonly Campylobacter jejuni enteritis or viral infections including influenza and COVID-19. Weakness progresses over days to 4 weeks, reaching its nadir — the point of worst function — within 28 days by definition. Approximately 25–30% of patients require mechanical ventilation at the nadir. Most patients improve with treatment (IVIG or plasma exchange), though recovery is often slow: weeks to months. Long-term follow-up is important as some patients develop CIDP — a chronic relapsing form of the same condition.

MUNIX (Motor Unit Number Index) is a quantitative electrophysiological technique that estimates the number of functional motor units in a muscle, providing an indirect measure of motor neuron survival. Unlike conventional EMG, which provides qualitative information, MUNIX gives a number — and that number can be tracked over time. In motor neuron disease (ALS, Hirayama disease), motor units are progressively lost as motor neurons die. MUNIX allows the neurologist to track this loss quantitatively, assess disease progression rate, and evaluate the effect of treatment. Dr. Sri Sai Srujana's first-prize research at IANCNPCON 2025 specifically demonstrated the utility of MUNIX in longitudinal monitoring of Hirayama disease patients.

Chronic inflammatory demyelinating polyneuropathy (CIDP) involves the same immune mechanism as GBS — immune attack on the myelin sheath of peripheral nerves — but follows a chronic course lasting more than 8 weeks, either progressively worsening or relapsing and remitting. Unlike GBS, CIDP does not typically follow infection and does not have a natural recovery phase. It requires ongoing treatment, usually with regular IVIG (intravenous immunoglobulin every 3–4 weeks), plasma exchange, or oral immunosuppression (prednisolone, azathioprine, mycophenolate mofetil). CIDP is often underdiagnosed because its gradual onset and predominantly sensory features can mimic other conditions. A detailed nerve conduction study showing specific demyelinating features is required to confirm the diagnosis.

Inflammatory myopathies are acquired autoimmune conditions causing muscle inflammation, weakness, and elevated CK (creatine kinase). Unlike muscular dystrophies — which are inherited genetic conditions causing progressive muscle degeneration — inflammatory myopathies are treatable with immunosuppression. The key inflammatory myopathies are polymyositis, dermatomyositis, anti-synthetase syndrome, immune-mediated necrotising myopathy (IMNM), and inclusion body myositis. Most respond to corticosteroids and immunosuppressive drugs such as azathioprine, mycophenolate mofetil, or rituximab. The diagnosis typically requires CK measurement, myositis antibody panel, muscle MRI, and muscle biopsy.

Hirayama disease (juvenile muscular atrophy of the distal upper extremity) is a benign, self-limiting condition primarily affecting young men, typically in their teens to late twenties, in South and Southeast Asia. It causes progressive wasting and weakness of the forearm and hand muscles — usually one-sided or predominantly on one side — which progresses for 3–5 years before stabilising. The underlying mechanism is forward displacement of the cervical dural sac during neck flexion, causing compression of the lower cervical anterior horn cells. Cervical MRI during neck flexion shows the characteristic forward shift of the posterior dura and flattening of the lower cervical cord. Early diagnosis is important because cervical collar immobilisation during the progressive phase can arrest or slow progression.

Muscle biopsy is indicated when the clinical picture and blood tests (CK, myositis antibodies) are consistent with a myopathy or muscular dystrophy but the specific diagnosis cannot be established without histological confirmation. It is particularly useful for: inflammatory myopathies where the diagnosis is uncertain · muscular dystrophies where genetic testing is not confirmatory · metabolic myopathies (e.g. Pompe disease) where specific enzyme deficiency needs to be demonstrated in muscle tissue · inclusion body myositis, which has characteristic pathological features on biopsy. The biopsy is usually performed under local anaesthesia as a day procedure, typically from the vastus lateralis or biceps brachii.

A standard course of IVIG for acute neuromuscular emergencies (myasthenia crisis, GBS) is administered over 5 days as an intravenous infusion: 0.4 g/kg/day for 5 days, giving a total dose of 2 g/kg. Each infusion lasts approximately 4–6 hours. For chronic conditions requiring maintenance IVIG (CIDP), the dose is typically 1–1.5 g/kg every 3–4 weeks, which can be administered over 1–2 days. IVIG is generally well-tolerated; the most common side effects are headache, fever, and chills during or after the infusion, which can be managed with paracetamol, slowing the infusion rate, or premedication.

Peripheral neuropathy is a broad term covering many different conditions affecting the peripheral nerves. For many patients with mild, stable sensorimotor neuropathy in a known context (diabetes, alcohol, vitamin B12 deficiency), a general neurologist's management is appropriate. A referral to a neuromuscular specialist is indicated when: the neuropathy is rapidly progressive · there is significant motor involvement (weakness, not just sensory symptoms) · the pattern is atypical (focal, asymmetric, or predominantly motor) · a treatable cause (CIDP, vasculitis, hereditary neuropathy) is suspected · the neuropathy has not responded to treatment of the underlying condition. The neuromuscular programme at KIMS can provide the detailed nerve conduction studies and clinical evaluation needed to characterise the neuropathy accurately.

Motor neuron disease (ALS) does not currently have a disease-modifying treatment that reverses progression. Riluzole modestly slows progression and extends survival by 2–3 months on average. Edaravone slows functional decline in a subset of patients in the early rapidly progressive stage. However, effective symptomatic management significantly improves quality of life and can extend the good-quality phase of the illness: spasticity management (baclofen, botulinum toxin), sialorrhoea treatment (anticholinergic medications, botulinum toxin to salivary glands), nutritional support (PEG tube when swallowing becomes compromised), non-invasive ventilation (BiPAP/NIV) for respiratory failure, and communication aids for dysarthria. Multidisciplinary management at KIMS coordinates all of these. Research into new disease-modifying treatments is active, and the programme keeps patients informed about relevant clinical trials.