Lupus Often Hard to Diagnose
"In mild forms of the disease, symptoms usually present in a confusing manner," Wofsy says. "Somebody comes in who is young with a variety of nonspecific symptoms, and a doctor may not be thinking about lupus. The person might complain about feeling tired in the afternoons or about feeling achy. A doctor could think that these symptoms might be due to stress or depression, or a virus."
One of the most frustrating things for someone with lupus is being sick, but feeling like nobody believes you, Ramirez says. "People think you're lazy or crazy, or both," she says. "You can also look nice and healthy, even though you feel very bad."
Before she was diagnosed with lupus, Ramirez battled mysterious symptoms for 10 years. She had five miscarriages, and later found out that women with lupus have higher rates of pregnancy loss. She also had:
- unexplained skin rashes
- pain in her legs and arms
- urinary tract infections
- kidney infections
- mouth sores
- overwhelming fatigue
In an unpublished study done in 1999, Isenberg and his colleagues asked 100 lupus patients what they were most worried about regarding their illness. "Their biggest concern was fatigue," Isenberg says. "They were worried about sleeping all night and still being exhausted in the morning or about feeling too tired to pick their children up from school or to do other things that they want to do."
As a former police officer and member of the military, Tony Chisholm, 46, of Fall City, Wash., was used to being active. Feeling wiped out from lupus sent him into a deep depression. "I just couldn't get out of bed," he says. "But nothing would show up on a physical exam."
He also has had bouts of flu symptoms, swelling around the eyes, joint pain, and chest pain. "Sometimes, the symptoms last for four months, and then I might go four more months without any problems," he says.
It was a photograph that finally helped Chisholm get some answers. In 1997, he and his family went to Great Britain for vacation and met another couple. The couple mailed Chisholm a photo from the trip. "The red butterfly rash across my face was plain as day," he says. "My wife insisted that I go to the doctor." After looking at the photo, the doctor ran tests for lupus. "Before that, I hadn't been diagnosed with anything else, except maybe hypochondria."
Diagnosis of Lupus
Early detection of lupus is important to lower the chance of organ damage and other complications. Doctors rely on:
- a patient's report of symptoms
- a medical history and exam
- blood and urine tests
"Lupus can lower blood counts and affect kidneys, causing protein and blood in the urine," Petri says. Doctors also may do skin or kidney biopsies, in which tissue is removed and examined for signs of autoimmune disease.
A commonly used test for lupus is the anti-nuclear antibody (ANA) test, which looks for autoantibodies that are reacting against the nucleus, also known as the command center, of the body's cells. "Most people with lupus have an elevated ANA, though a few rare patients have a negative ANA," Petri says. But a positive ANA isn't enough to confirm lupus. "Twenty percent of healthy women can have a positive ANA," she says. The ANA also detects other autoimmune diseases, including:
So if the ANA test is positive, more specific testing is used to confirm a lupus diagnosis. Doctors test for complement components, a group of proteins in the blood that help destroy bacteria. Low complement levels can be associated with lupus. Doctors also do blood tests for antibodies to DNA and for other cell nuclear components. Two specific tests for lupus are:
- the anti-double-stranded DNA (anti-dsDNA) antibody test
- the Smith antibody (anti-Sm) test
"Lupus is an unpredictable disease, but certain antibodies help to make some predictions," Petri says. For example, people with anti-dsDNA or low complement are more likely to develop kidney disease, she says. And some women with lupus have a syndrome in which antiphospholipid antibodies cause blood clots. This syndrome is associated with miscarriages, strokes, and deep vein thrombosis.
The American College of Rheumatology says that to be diagnosed as having lupus, a person should meet at least four of the following clinical and laboratory criteria:
- rash over the cheek
- red, raised patches (discoid rash)
- ulcers in the nose or mouth
- arthritis (non-erosive arthritis in which the bones around the joints don't become destroyed)
- inflammation of the lining of the heart or lung (pleuritis or pericarditis)
- kidney disorder (excessive protein in the urine or cellular casts, or both)
- neurological disorders (such as seizures, convulsions, or psychosis)
- blood (hematologic) disorders (such as repeated low blood cell counts)
- positive ANA test
- immunologic disorders