What is myasthenia gravis? The disease that Monica Seles suffers

For those who don't know Monica Seles in 2025, let me just say that before she turned 20, she had already made history in women's tennis.

Born in Serbia and a naturalized American, her aggressive, uncompromising left-handed game led her to eight Grand Slam titles as a teenager, adding a ninth in 1996, at just 23 years old. She reigned in the world rankings for 178 weeks (almost three and a half years) with a total of 53 trophies.

But on April 30, 1993, in Hamburg, an act as absurd as it was atrocious halted her meteoric rise: a man burst from the stands and stabbed her in the back. The attacker, Günter Parche, confessed that his goal was to favor his idol, Steffi Graf, with whom Seles competed at the top of tennis. That physical wound took weeks to heal; the emotional one, perhaps never completely. Even so, Seles returned, won another major, and retired in 2003, leaving the impression that, had that attack not occurred, her legend would be even greater.

But yesterday, August 13, 2025, Monica was back in the news.

Monica broke her silence about a battle she had kept private for almost three years: myasthenia gravis. Seles recounted that her first signs came during a friendly tennis match with family members, when she suddenly saw two balls instead of one. After months of diagnosis and adaptation, she decided to go public and join the "Go for Greater" campaign with the pharmaceutical company Argenx, with the aim of raising awareness of the real impact of this condition. As in her career, she now faces a difficult opponent, with the same determination that led her to return to the court after her attack in Hamburg.

Today we explain what disease he is suffering from.

What is myasthenia gravis?

Myasthenia gravis is a neuromuscular, autoimmune, and chronic disease, three adjectives that, together, accurately describe the nature of this medical challenge.

• It is neuromuscular because its epicenter is at the junction between nerve and muscle, where the electrical impulse originating in the nervous system must be translated into movement, a bridge that is obstructed in this condition.
• It's autoimmune because the body's own defense system, in a mistaken identity, produces antibodies that attack acetylcholine receptors, sabotaging communication between nerve cells and muscle fibers. This prevents the muscle from contracting and generates that feeling of weakness.
• And it is chronic because, although its symptoms may fluctuate or improve with treatment, the condition accompanies the patient for life, requiring constant adaptation and ongoing medical monitoring.

Screening for myasthenia gravis

The onset may be unusual tiredness in the eyelids, which slowly droop at the end of the day; vision that suddenly doubles; or a strange fatigue when chewing or speaking, as if such automatic tasks have become burdensome. At first, these symptoms tend to fluctuate: they improve with rest and worsen with exertion, which often delays suspicion. The patient feels like they "have no strength," not because of a lack of energy, but because the nerve signal isn't reaching the muscle with sufficient intensity. Thus, the disease progresses quietly, gradually affecting muscles in the face, neck, arms, or even breathing.

The diagnosis of myasthenia gravis is an exercise in clinical and laboratory precision.

• It begins with a detailed history of symptoms and a neurological examination looking for signs of fatigable muscle weakness.
• From there, the neurologist may use tests such as detecting anti-acetylcholine receptor or anti-MuSK antibodies in the blood, which confirm the autoimmune origin.
• Repetitive stimulation electromyography measures the muscle's electrical response to successive impulses, revealing the failure in transmission.
• In some cases, the edrophonium test, which is less common today, or the ice test on a drooping eyelid is used to observe whether there is a temporary improvement.
• Finally, a CT scan or MRI of the mediastinum aims to rule out thymoma, a tumor associated with it in a significant percentage of cases.

Diagnosing myasthenia gravis is complicated because its initial symptoms can mimic other neurological or muscular disorders.

• Drooping eyelids and double vision, for example, may suggest oculomotor nerve paralysis or multiple sclerosis.
• Weakness in arms and legs can be confused with inflammatory myopathies, muscular dystrophies, or even chronic fatigue.
• Difficulty speaking or swallowing may lead to suspicion of amyotrophic lateral sclerosis or mild stroke.

Added to this is the fact that myasthenia gravis doesn't always affect the same muscles or with the same intensity throughout the day, which can confuse both patients and physicians. This changing nature and the lack of clear findings on standard imaging tests require a high degree of clinical suspicion and a combination of neurological examination, specific tests, and electrophysiological studies to arrive at the correct diagnosis.

Treatment of myasthenia gravis

The therapeutic approach to myasthenia gravis is, in essence, a balance between controlling the symptoms and modulating the immune response that causes them.

• In the first line, acetylcholinesterase inhibitors, such as pyridostigmine, are used, which prolong the action of acetylcholine at the neuromuscular junction and temporarily improve muscle strength.
• To contain the autoimmune attack, corticosteroids and immunosuppressive drugs such as azathioprine, mycophenolate, or cyclosporine are used to reduce the production of pathological antibodies.
• In cases of severe exacerbations or myasthenic crises, where breathing is at risk, plasmapheresis and intravenous immunoglobulin act as emergency maneuvers, eliminating or blocking circulating antibodies.
• When a thymoma is detected, thymectomy (surgical removal of the thymus) may not only resolve the tumor problem, but also improve the course of the disease.

Beyond medications and surgical interventions, treatment includes careful lifestyle adjustment and effort planning, since in myasthenia gravis, avoiding overexertion and managing rest are just as important as medications.

The neurologist must fine-tune the dose and combination of drugs according to the patient's progress, avoiding the adverse effects of excessive immunosuppression and maintaining functional capacity.

Therapy is almost always long-term, and success depends on a close partnership between patient and medical team, where each adjustment is a step in the choreography that seeks to restore strength and autonomy without compromising the body's protection.

Evolution of myasthenia gravis

Myasthenia gravis is as variable as its sufferers. In some cases, symptoms are limited to the eye muscles and remain stable for years; in others, the disease progresses to a generalized form affecting the arms, legs, neck, and even the respiratory muscles.

The course is often marked by fluctuations: periods of relative stability interspersed with relapses, sometimes precipitated by infections, stress, or hormonal changes. Thanks to current treatments, most patients achieve an acceptable quality of life, and severe attacks, which were life-threatening in the modern era, are much less common today.

Long-term outcomes depend on multiple factors: age at onset, the presence of thymoma, response to medication, and management of comorbidities. Some patients achieve prolonged remissions and, in select cases, even significant improvements after thymectomy. Others require ongoing treatment to keep weakness at bay. In any scenario, living with myasthenia gravis involves learning to recognize the warning signs, anticipating attacks, and living with the uncertainty of a chronic disease, but with the certainty that modern medicine offers increasingly refined tools to keep it under control.

I hope Monica reads this article one day, and if she does, we send her all our encouragement as she faces her illness. Monica is being very brave (as she always has been) by sharing this and bringing awareness to this condition, and we're sure it will help other sufferers cope with this illness in the best possible way.