Mary Lou Retton excelled against her competitors to win an Olympic gold medal in 1984 — but now the 55-year-old American gymnastics icon faces a more challenging opponent.

On a fundraising page earlier this month, Retton’s daughter, McKenna Kelley, wrote that her mother "has a very rare form of pneumonia and is fighting for her life," adding that she had been in the ICU and was not able to breathe on her own.

Earlier this week, in the first update in four days, Shayla Kelley Schrepfer, another daughter of Retton's, related that things seemed like they were headed "on the up and up" — but then they took a turn for the worse on Tuesday.

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"We were so excited seeing so much progress," Schrepfer said in an Instagram post. 

"And then yesterday, we had a pretty scary setback."

Mary Lou Retton looks on during a competition

Mary Lou Retton, Olympic gold medalist in women's gymnastics, is currently in the ICU with life-threatening pneumonia. (Jonathan Daniel/Getty Images)

The details of the setback were not disclosed.

But Schrepfer said that Retton had a "better day" on Wednesday and that she was "just really, really exhausted," as she remains in the ICU.

Prevalence and symptoms of pneumonia

Though the exact cause of Retton’s pneumonia is not known, the condition can be life-threatening — and many Americans battle it each year.

The Centers for Disease Control and Prevention (CDC)’s website indicates that 1.4 million emergency department visits were due to pneumonia in 2021.

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"It leads to more than one million hospitalizations and more than 50,000 deaths per year," said Dr. Fred Davis, associate chair of emergency medicine at Northwell Health Long Island Jewish Medical Center on Long Island, New York.

"Pneumonia is an infection of the lungs that can be caused by viruses, bacteria and fungi, which leads to inflammation and a buildup of fluid, causing issues with oxygenation," Davis told Fox News Digital.

Woman coughing

Some common warning signs of the illness include cough, fever and shortness of breath. (iStock)

Common causes of viral pneumonia in the U.S. include influenza (flu), respiratory syncytial virus (RSV) and SARS-CoV-2 (the virus that causes COVID-19), according to the CDC.   

Bacterial pneumonia is commonly caused by streptococcus pneumoniae (pneumococcus) and, typically in kids, mycoplasma pneumoniae.

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Some common warning signs of the illness include cough, fever and shortness of breath.

"When shortness of breath occurs or you notice discoloration around [the] fingers, toes or lips, it is important to seek emergent care," Davis warned.

Typical treatments for pneumonia

Treatment for pneumonia depends on the cause, the doctor noted.

In cases of viral infections, he recommends supportive care like rest and fluids.

For bacterial cases, antibiotics are the most common course of treatment.

Fungal infections can be treated with antifungal medications. 

Tripledemic viruses

Common causes of viral pneumonia in the U.S. include influenza (flu), respiratory syncytial virus (RSV) and SARS-CoV-2 (the virus that causes COVID-19), according to the CDC.  (iStock)

In severe cases, the patient may be admitted for monitoring and given supplemental oxygen, Davis told Fox News Digital.

Dr. Aaron Glatt, chair and professor of medicine at Mount Sinai South Nassau in Oceanside, New York, said that for most bacterial pneumonia, antibacterial therapy with antibiotics can be effective — "but it's not always perfect and it doesn't always work." 

Glatt added, "It often depends on how severe the underlying condition is with that person."

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When it comes to viral pneumonia, the infectious disease expert said treatment can be more challenging.

"You don't have as many good agents," he said. "It will depend on which virus you're dealing with."

Regarding fungal pneumonia, Glatt said treatment will depend on what type of fungus is causing the pneumonia. 

Person on ventilator

In severe cases, the patient may be admitted for monitoring and given supplemental oxygen, a doctor told Fox News Digital. (iStock)

"Often these patients are extremely sick and have a worse prognosis," he said.

In different parts of the country, there are different types of fungi that can contribute to pneumonia.

For example, histoplasmosis is common in the middle of the U.S., Glatt said.

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Although anyone can get the infection, "those who are young, are older than 65 or have weakened immune systems are at greater risk of a bad outcome should they get pneumonia," Davis told Fox News Digital.

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The best way to avoid pneumonia is to reduce the risk of infection by following proper hand hygiene, covering your mouth when sneezing and washing your hands immediately afterward, he said.

Mary Lou Retton with her gold medal

American Olympic gymnast Mary Lou Retton holds up her gold medal at a press conference during the 1984 Summer Games in Los Angeles. While Retton excelled against her competitors to win Olympic gold in 1984 — today the 55-year-old gymnastics icon faces a more challenging opponent. (Getty Images)

He also recommended getting the flu shot, as influenza is a common cause of infection and the vaccine can reduce the risk — "especially in those younger than 2 years old and greater than 65 years old, who are more at risk should they get infected," Davis noted.

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The CDC also recommended monitoring and treating any underlying medical conditions such as asthma, diabetes and heart disease, as well as speaking with a health care provider about vaccinations to help prevent pneumonia.

Sarah Rumpf-Whitten contributed reporting.

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