Amyotrophic Lateral Sclerosis (ALS): symptoms to recognise the disease

By Cristiano Antonino On Oct 19, 2022

Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease characterised by motor neuron degeneration that initially leads to impaired motor functions (up to total muscular paralysis) and subsequently impairs vital functions (swallowing, phonation, breathing) but spares cognitive, sensory, sexual and sphincter functions

ALS is also known as Charcot’s disease (from Jean-Martin Charcot, the name of the French neurologist who first described it in 1860) or as Lou Gehrig’s disease, (from the name of the famous American baseball player who was affected).

How widespread is Amyotrophic Lateral Sclerosis ALS

Amyotrophic Lateral Sclerosis is a rare disease.

In Europe, there are approximately 1.5 – 2.5 cases of the disease per 100,000 inhabitants.

According to the Osservatorio Malattie Rare (Rare Disease Observatory) in Italy, there are an estimated 3500 patients and 1000 new cases per year.

RARE DISEASES? TO LEARN MORE VISIT THE UNIAMO – ITALIAN FEDERATION OF RARE DISEASES BOOTH AT EMERGENCY EXPO

What are the causes of ALS

Little is still known about the causes of Amyotrophic Lateral Sclerosis.

What is certain is that it is a disease with a multifactorial origin between genes and environment.

In almost all cases ALS is sporadic, i.e. without familial inheritance.

Familial forms account for only 5-10% of the total number of patients.

Of these, 20% are associated with a structural mutation in a gene coding for superoxide dismutase (SOD), an enzyme that contributes to the removal of free radicals from the body.

Only a small percentage of hereditary cases have no gene mutations.

Among the main hypotheses that could lead to neurodegeneration are:

glutamate
free radicals and oxidative stress
cytoplasmic protein aggregates
mitochondrial dysfunction
altered axonal transport processes
inflammation of the nervous system
the lack of substances responsible for motor neuron growth and function.

The role of environmental factors, and in particular pesticides, heavy metals and magnetic fields, remains to be clarified.

Signs and symptoms of Amyotrophic Lateral Sclerosis

ALS is an adult-onset disease that usually begins around the age of 50.

It often presents with non-specific initial symptoms and progresses silently to manifest itself with:

muscle weakness in the upper and lower limbs
reduced strength
slowness
difficulty in movements
involuntary muscle contractions (fasciculations)
paralysis

Even in the most advanced stages, the disease does not affect the internal organs or the five senses.

In most cases, sexual functions are preserved.

Even cognitive abilities are not affected by the neurodegenerative process of ALS, which leaves the person in full mental capacity despite the progression of the clinical picture.

Just like the onset symptoms and their severity, the course of the disease also varies depending on certain conditions and from one patient to another: the prognosis is usually worse the older the disease begins, in the case of ALS of the bulbar type (i.e. when the lesion is linked to the motor neurons of the brainstem/bulbar) and when there is early respiratory failure.

Diagnosis of Amyotrophic Lateral Sclerosis

Diagnosis of ALS is particularly difficult because it must include exclusion, through appropriate tests, of other diseases that mimic ALS since the symptoms of Amyotrophic Lateral Sclerosis may be similar to those of a wide variety of other diseases and conditions.

Based on the application of international diagnostic criteria, the following are used as diagnostic support for the clinical picture

Electromyography (EMG) for the assessment of peripheral nerve and muscle function;
Nuclear Magnetic Resonance Imaging (NMR) for studying the pyramidal system;
PET (Positron Emission Tomography) to study the functional metabolism of different brain areas.