15 symptoms of pneumonia explained as Diane Keaton's cause of death confirmed

Diane Keaton died of pneumonia, her family confirmed in a statement.

The legendary actress passed away at the age of 79 on Saturday October 11.

The Los Angeles Fire Department confirmed they rushed to Keaton's home just after 8am, with paramedics also on the scene.

A spokesperson for her family confirmed Keaton died in California, but no further details were immediately available.

Since, the Godfather actress' family have expressed their gratitude for the outpouring of love and support.

“The Keaton family are very grateful for the extraordinary messages of love and support they have received these past few days on behalf of their beloved Diane, who passed away from pneumonia on October 11,” the statement, issued to People, read.

It continued: "She loved her animals and she was steadfast in her support of the unhoused community, so any donations in her memory to a local food bank or an animal shelter would be a wonderful and much appreciated tribute to her."

Diane Keaton starred as Kay Corleone in The Godfather (Paramount Pictures/CBS via Getty Images)

More than one million people in the US are hospitalized with pneumonia every year as per UCLA Health, with 50,000 people dying from it each year.

What causes pneumonia?

Pneumonia is a lung infection brought on by either bacteria, a virus, or fungi, Cleveland Clinic explains.

It causes the lung tissue to swell and can produce fluid or pus in the lungs.

Common illnesses, including a cold, the coronavirus, the flu and pneumococcal disease, can lead to pneumonia.

In some cases, streptococcus pneumoniae bacteria can cause pneumonia (Kateryna Kon/Science Photo Library/Getty Images)

In some cases, pneumonia develops when your immune system attacks an infection in the small sacs of your lung, called the alveoli.

People aged 65 or older, who have a heart or lung condition, who smoke or are pregnant are at higher risk of developing the disease.

What are the symptoms of pneumonia?

Shortness of breath is one symptom of pneumonia (Staras/Getty Images)

Bacterial and viral pneumonia might present in slightly different ways.

Symptoms of the former can develop either gradually or suddenly, while the latter usually comes on over several days.

Warning signs of bacterial pneumonia include:

• a high fever, of up to 105 F (40.55 C)
• a loss of appetite
• sweating or chills
• rapid breathing
• shortness of breath
• a cough with yellow, green or bloody mucus
• a rapid heart rate
• blue-tinted lips, nails or skin
• fatigue
• confusion
• pain in the chest or the abdomen, particularly when taking deep breaths or coughing

Symptoms of viral pneumonia might be similar to the ones listed above, but could also include:

• a dry cough
• muscle pain
• headache
• 'extreme' tiredness or weakness.

If you have any concerns, contact your GP right away.