What is sepsis? Here's everything to know about the infection former president Bill Clinton is battling - USA TODAY

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Former President Bill Clinton continues to recover from a non-COVID-related infection after being hospitalized at the University of California Irvine Medical Center Tuesday.

Clinton, 75, was admitted into the hospital's intensive care unit for a urinary tract infection that spread to his blood, clinically known as sepsis, according to multiple new outlets.

A statement from Clinton's spokesman Angel Ureña said the former president is "on the mend" and "in good spirits" after receiving two days of treatment that included antibiotics and fluids administered through an IV.

"His white blood cell count is trending down and he is responding to the antibiotics well," Clinton's doctors Dr. Alpesh Amin and Dr. Lisa Bardack said in a statement. "We hope to have him go home soon."

Doctors say sepsis is most commonly seen in elderly patients, and Clinton is not the first former president has had it. Former president George H.W. Bush was also admitted to the hospital with sepsis in 2018, a day after his wife's funeral.

According to the World Health Organization, sepsis kills more than 11 million people in the world each year. Here's everything to know about the potentially fatal infection. 

What is a urinary tract infection, or UTI?

A urinary tract infection, or UTI, is an infection in any part of the urinary system including the kidneys, ureters, bladder and urethra, according to the Mayo Clinic. UTIs typically occur when bacteria enters the urinary tract through the urethra and multiplies in the bladder.

Most infections occur in the lower urinary tract involving the bladder or the urethra.

"UTIs are one of the most common causes of sepsis, but these are more common in women than men," said Dr. Faisal Masud, director of critical care at Houston Methodist Hospital. 

Symptoms include a strong and persistent urge to urinate but only passing small amounts, accompanied by a burning sensation and pelvic pain, the Mayo Clinic says. 

But symptoms may differ depending on where the infection is located. If the infection is in the kidneys, patients may experience back pain or side pain, high fever, shaking, chills, nausea and vomiting.

An infection in the bladder could result in pelvic pressure, lower abdomen discomfort, frequent and painful urination, and blood in urine. Patients may experience a burning with urination or see discharge if the infection is in the urethra.

"We encourage all patients, not only the elderly, when they have these kinds of symptoms, to specifically ask their medical provider, 'Do I have sepsis?'" Masud said. 

Doctors typically treat UTIs with antibiotics.

What is sepsis?

Doctors say sepsis stems from any bacterial infection – like pneumonia, an aggressive skin infection, a gastrointestinal infection or a UTI.

The infection spreads through the bloodstream causing symptoms such as fever, chills, low blood pressure, rapid breathing, elevated heart rate, along with confusion and disorientation, health experts say.

"When elderly people become lethargic, confused, are more fatigued, they may or may not have a fever, then these are possible sepsis symptoms and a good reason to seek medical care immediately," Masud said. 

Sepsis can also cause the body to overreact to an infection where inflammatory compounds that help fight the infection also end up damaging organs such as the kidney, lungs, heart, or the brain, said Dr. Robert Glatter, an emergency physician at Lenox Hill Hospital in New York City. 

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"Sepsis can be deadly if not promptly recognized and aggressively treated,' he said. "Studies have shown that early recognition and intervention with intravenous fluids and broad spectrum intravenous antibiotics can be lifesaving."

Patients who are septic need close and continuous monitoring of their vital signs to maintain normal levels of oxygen in their bloodstream to reduce the risk of septic shock. This occurs when blood pressure becomes dangerously low making it harder for organs to receive blood and function normally.

With sepsis, patients tend to breathe faster to maintain normal oxygen levels and, in some cases, may require a ventilator. Glatter said it's important to monitor white blood count, as mentioned by Clinton's doctors.

"Dropping platelet counts can signal worsening of sepsis and monitoring different populations of white blood cells can help predict the severity of illness," Glatter said. "The fact that President Clinton's vital signs have improved and that his white blood count is now lower demonstrates that he is clinically improving."

Follow Adrianna Rodriguez on Twitter: @AdriannaUSAT. 

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