If you go What: Walk to Cure Psoriasis When: 8 a.m. Sunday, May 20 Where: Sloan’s Lake Park, Sheridan Boulevard and West 17th Avenue, Denver Cost: Free Information: Visit walk.psoriasis.org or call 877-825-WALK (8255)

LONGMONT — Every month, a delivery person rings the doorbell at the Knight residence and drops off a 20-pound bag of salt from the Dead Sea.

Nosy neighbors might find this curious.

But Melanie Knight, 12, needs two cups of the salt, along with two tablespoons of sulfur powder, to mix in the hot baths she takes to slough off the scaly dead skin that covers more than 80 percent of her body.

Though she was born with clear skin, doctors diagnosed her with an extremely severe case of psoriasis at age 2, and for years she felt too self-conscious to wear black — which shows skin flakes — a bikini or standard summer attire such as shorts and T-shirts.

Kids and adults often asked her if she had chicken pox.

Others treated her like a modern-day leper, even though psoriasis is not contagious and can be treated with ointments and internal medications.

“When I was in third grade, this girl in fourth grade used to give me these dirty looks, like I was disgusting or revolting and like she smelled something bad every time she passed me,” Knight said.

The painful experience could have forced Knight into hiding.

Instead, with the support of her parents — both of whom have milder cases of psoriasis, a genetically linked condition — Knight in 2010 decided to help raise awareness as a youth ambassador for the Portland-based National Psoriasis Foundation.

This year, she already has raised more than $2,000 for the Walk to Cure Psoriasis in Denver on May 20.

She also has honed her talking points to remind that an estimated 7.5 million people in the United States, about 2.2 percent of the population, have psoriasis, the most common autoimmune condition in this family of about 80 disorders including rheumetoid arthritis, lupus and Celiac disease.

Autoimmune conditions happen when, for mysterious reasons, the body’s immune system misdirects an attack on its own tissues. In this case, the immune system sends out faulty signals that speed up the growth cycle of skin cells.

Mapping the condition

The surface area of the hand equals about 1 percent of the skin, according to the National Psoriasis Foundation.

In mild cases, where the condition flares up on a 3 percent or less area of the skin, many people figure that they just have a bad case of dandruff or stubbornly dry elbows, Longmont Clinic dermatologist Dr. Scott Clark said.

However, about a third of those diagnosed with psoriasis — typically between ages 15 and 25 — fall into the moderate to severe categories where various types of rashes cover between 3 and 10 percent of the skin or 10 percent or more of the skin, respectively.

Those cases can weaken the immune system, which makes patients more sickly. For instance, Knight missed 22 days of school this year due to persistent colds and illnesses that triggered skin flare-ups and made her feel rundown and in need of extra rest.

Now, she has a “504,” an academic accommodation that gives the straight-A student more time to turn in homework after absences.

Still, living with such a widespread rash can cause intense itchiness and self-consciousness.

“If you’re uncomfortable in your skin, imagine how irritating that can be,” Clark said. “… Some studies show that only people with severe depression tend to do worse in terms of quality of life, and those studies include people getting treated for cancer.”

He added that other conditions, such as diabetes and heart disease, present at greater rates in people diagnosed with psoriasis than in people in the general population.

“Although we’re still trying to find out more about this chicken-or-egg question,” Clark said.

Taking charge

To cope well, Melanie Knight follows her doctor’s orders to manage stress, which can trigger flare-ups.

At school, she keeps herself from scratching or picking at her skin by playing with a sensory therapy toy called a Tangle — a plastic, snake-like toy with multiple joints — under her desk. During band rehearsals, she fingers her oboe keys when not playing to keep her hands busy and her mind off her skin.

At home, she cuddles one of her three guinea pigs — Lilly, Skipper or Skyla — while reading, one of her favorite pastimes.

She also cooperates with her mother to painstakingly apply topical ointments, some of which include steroids to reduce inflammation, to her rough skin every night after her bath or shower.

This fall delivered a setback when she was diagnosed with juvenile psoriatic arthritis.

“After that, she didn’t want to go to the doctor anymore,” Shayla Knight, her mother, said. “She said, ‘I’m just scared that the doctor will find something else wrong with me.'”

Yet, Melanie Knight managed to rally again through her youth ambassador role — something her mother credited for giving her daughter a greater sense of control and inspiring her to do something about her situation.

This year, Melanie Knight sold about $700 of her Cards for a Cure and donated all profits to the National Psoriasis Foundation. The cards feature her photographs of flowers, fireworks and more on the front and the slogan — “Life’s most beautiful things are not seen with the eyes, but felt with the heart” — on the back. Magic Fairy Candles in Longmont and The Bookworm in Boulder now display them.

Ice skates and blue jeans that bunch around the back of her knees when she sits still irritate her skin beyond what she can handle.

“But I don’t think psoriasis is horrible. You’re not going to die because of it,” Melanie Knight said. “… Some people at my school are black or Mexican or white. I’m just spotted. I am a short giraffe.”

Pam Mellskog can be reached at 303-684-5224 or pmellskog@times-call.com.