(CNN) -- Atundra Horne walks along the battered cement pathway to her patient's home with a set jaw and a solemn face. A computer with patient records is slung over her shoulder; a backpack stuffed with gauze, bandages and other medical equipment rolls behind her.
Horne is a home health nurse, and her patients live in some of the roughest areas in Chicago. On this day she is working in Auburn Gresham, a neighborhood on the South Side. Horne's workplace is far from water coolers and cubicles; instead, she says, it involves drugs, prostitution and the occasional clap of gunfire.
"There is a lot of crime," said Horne, who has been a nurse for 14 years. "It is a danger you face every day that you're out here."
The threat of danger is so acute that trailing a few steps behind Horne is a security officer toting a loaded gun.
A year and a half ago it became standard protocol for Horne and her colleagues at Advocate Health Care to travel with armed security officers, who offer protection while the nurses treat patients.
They need the help. In 2012 there were more than 500 homicides in Chicago, many caused by guns, according to local crime statistics. The deaths tend to be concentrated in the South Side neighborhoods that Horne and her colleagues visit every day.
"There are people hanging out on street corners, there are drug dealers congregating," nurse Beth Kairis said, describing the rough areas where she works. "You see different crime scenes and makeshift memorials for people who were shot the night before."
Kairis recalled a recent visit to care for a baby who was quite ill. As she and the security officer pulled up to the house, they found out there had just been a shooting less than a block away. Mobs of people filled the street; the situation was dangerous.
Leaving the baby without care was not an option, but neither was entering the home under unsafe circumstances. Kairis said she ended up being ushered in and out of the home by a group of police officers.
"Sometimes it's unnerving just to get out of the car," said Kairis. "Sometimes (after a visit) I get back in the car and think, 'I know nine out of 10 people would not have gone into that house. Am I crazy?"
For her own peace of mind, Kairis recently devised a plan for avoiding problems. The night before she does home visits, Kairis studies her patient roster and the neighborhoods where patients live. She tries to cluster her calls for efficiency and safety.
"We hit the worst areas earlier in the day, then not-so-bad areas later in the day," said Kairis, who has been a nurse for six years. "Occasionally when something is going on in an area, we might have to change course a little bit and revisit that area later."
Changing course means patients in relatively better health may have their care delayed for a few hours, said Kairis. Some of the sickest patients may have to receive care at a friend or relative's house until the danger at their own home subsides.
At each home, the security officer, usually a retired or off-duty Chicago cop, often will enter a residence to ensure it is safe and then keep watch outside.
"We keep an eye on all this stuff so that the clinician can do what she needs to do without fearing for her safety," said Tom Flanagan, a retired police officer and president of Accord Detective Agency, a company that provides security for Advocate's nurses.
In the car between calls, the nurses prepare for the next patient while a police scanner drones on in the background. Officers will change their route if the scanner suggests a safety issue.
To say this is an unusual workplace arrangement is an understatement, said Kairis. But she has little fear most of the time because she has protection. Her patients, who often have no choice but to live in these neighborhoods, cannot say the same.
"My patients truly live as prisoners in their own homes," said Kairis. "No sooner do I get my foot in the door, they get the door bolted shut, the alarm activated. It's sad because they live afraid in their own homes, and they're dealing with sickness on top of that."
Many of her patients have cancer, and Kairis treats them with infusions of chemotherapy drugs. Other patients are gunshot victims. One is a 15 year-old boy who was hit by random gunfire in his neighborhood.
The boy, said Kairis, is now paralyzed.
Still, despite the inherent danger involved with her job, Kairis said she derives strength and the courage to continue providing care from the patients themselves.
"I am forever changed by these amazing people," said Kairis. "They have to motivate twice. Motivate because they are dealing with horrific sicknesses or the end of their life, and then you walk into their neighborhoods and there are drug dealers everywhere.
"This is what they're dealing with, yet they're still able to overcome, to go on with their day."
Horne said the care she is providing is personal, intertwined with her own history. She grew up in Englewood, another neighborhood on the South Side weighed down by gun violence, and witnessed violence firsthand.
She also said she feels drawn to Englewood by her mother and grandmother, who still live in the neighborhood. The patients there are, in essence, her people.
"I do it because I care about the patients," said Horne. "That's the No. 1 reason I'm out there. I care about my job and the services we provide to these patients. They can't help the communities they're in."