By Dr. Jamin Brahmbhatt, CNN
(CNN) — The death of NASCAR Cup Series champion Kyle Busch, whose family said he had severe pneumonia that progressed to sepsis, has renewed questions about a condition many people have heard of but few fully understand.
Sepsis is more common and more unpredictable than most people realize.
As a urologist, I frequently care for patients who arrive in the emergency room with infected kidney stones. The symptoms often started days earlier: flank pain, fevers, chills, nausea or a general feeling that something was not right. By the time they get to the emergency room, some look visibly ill: heart rate up, blood pressure low, tired and sometimes confused.
This is no longer just an infection. This is sepsis, the body’s extreme response to infection.
Pneumonia isn’t the only infection that can lead to sepsis. A skin infection that keeps spreading and raises your heart rate. A urinary tract infection that suddenly lowers your blood pressure. An infected kidney stone that raises your temperature – these are not just infections anymore. They could be sepsis.
How common sepsis really is
About 1.7 million adults in the United States develop sepsis each year, and at least 350,000 die during hospitalization or are discharged to hospice, according to the US Centers for Disease Control and Prevention. Sepsis contributes to more than one-third of hospital deaths in this country.
Yet public awareness remains surprisingly low. Many people still do not recognize the symptoms or realize that common infections can trigger it.
When your medical team suspects sepsis, the clock starts. We start IV fluids and broad-spectrum antibiotics within the first hour, and then we look for the source of the original infection.
I have seen patients walk in barely able to talk who are then sitting up and asking for water a few hours later. But not every case follows the same course. Some arrive early , get aggressive treatment and still end up in the ICU.
Sepsis can be unpredictable, and that’s why early recognition matters so much.
What sepsis does to the body
Many people think of infections as staying in one part of the body. Pneumonia affects the lungs. A urinary infection affects the bladder. A skin infection stays in the skin.
Sometimes that is true. But when sepsis develops, the body’s response can become much larger than the original infection.
Sepsis is like a kitchen fire that triggers sprinklers throughout an entire building. The original problem may start in one area, but suddenly the emergency response spreads much farther than intended or needed. The body is trying to contain the threat. But in some situations, the inflammatory response becomes wide enough that blood pressure falls, oxygen levels suffer and organs begin to fail.
That is what makes sepsis dangerous. The infection matters, but the body’s response matters just as much, if not more.
Where sepsis begins
Busch’s death has put the spotlight on pneumonia, but it is only one possible cause of sepsis.
Pneumonia happens when infection and inflammation affect the lungs, making it harder for oxygen to move through the body. Many cases improve with treatment, and recovery is common. But severe pneumonia can progress and, in certain situations, contribute to sepsis.
Sepsis can also develop from urinary infections, kidney stones, issues inside the abdomen, skin wounds and surgical sites.
In urology, infected obstructed kidney stones are one of the more dangerous examples. Bacteria become trapped behind a blockage, and the body cannot cl