The mosquito-bornechikungunya virus causes joint pain and swelling similar to rheumatoid arthritis, which can make diagnosis difficult, a new study says.Chikungunya has spread in parts of the Caribbean and Central and South America. Though still rare, the virus is increasingly being seen in the United States, according to the researchers.
78. "Wheresoever you
may be, death will overtake you even if you are in fortresses built up strong
and high!" And if some good reaches them, they say, "This is from
Allah," but if some evil befalls them, they say, "This is from you (O
Muhammad )." Say: "All
things are from Allah," so what is wrong with these people that they fail
to understand any word?
79. Whatever of good reaches
you, is from Allah, but whatever of evil befalls you, is from
yourself. And We have sent you (O Muhammad ) as a Messenger to mankind, and Allah
is Sufficient as a Witness.
80. He who obeys the
Messenger (Muhammad ), has indeed
obeyed Allah, but he who turns away, then we have not sent you (O Muhammad ) as a watcher over them.
81. They say: "We are
obedient," but when they leave you (Muhammad ), a section of them spend all night
in planning other than what you say. But Allah records their nightly
(plots). So turn aside from them (do not punish them), and put your trust
in Allah. And Allah is Ever All-Sufficient as a Disposer of affairs.
82. Do they not then
consider the Qur'an carefully? Had it been from other than Allah, they would
surely have found therein much contradictions.
Adding to the potential confusion in making a diagnosis, the researchers also found that blood tests of patients with chikungunya can have similar results to people with rheumatoid arthritis.
In many people, chikungunya infection causes fever, rash, and joint pain in the hands, feet, knees, neck and elbows. The fever and rash typically ease in seven to 10 days. But joint pain lasts for 12 to 15 months in up to 60 percent of patients. In some patients, joint pain lasts for up to three years, according to the researchers.
The study included 10 St. Louis-area residents who were infected with the chikungunya virus during a 2014 trip to Haiti. They were evaluated seven to 10 weeks after symptoms began and compared with people who had rheumatoid arthritis.
Eight of these patients developed persistent arthritis, according to the researchers at Washington University School of Medicine in St. Louis.
"All eight patients with chikungunya-related arthritis met the American College of Rheumatology's criteria for a diagnosis of rheumatoid arthritis," said the study's lead author, Dr. Jonathan Miner, in a university news release.
The study was published recently in Arthritis and Rheumatology.
The chikungunya virus was first identified 60 years ago in Africa and has since spread to other parts of the world. According to the U.S. Centers for Disease Control and Prevention, more than 2,000 people in the United States were diagnosed with chikungunya infection in 2014 after traveling to other countries, mostly the Caribbean.
That same year, the CDC reported 11 cases of chikungunya among people living in Florida who had not traveled outside of the country, suggesting that mosquitoes in the state were spreading the virus.
The findings about the similarities between patients with chikungunya infection and rheumatoid arthritis show the need for doctors to get detailed travel and medical histories from patients, the researchers noted.
"For now, good travel histories of patients are among the best diagnostic tools for physicians," study senior author Dr. Wayne Yokoyama, a professor of medicine at the university, said in the news release.
"Recent travel to the Caribbean, Central and South America, Africa, India or other areas where the virus is prevalent should raise suspicions of chikungunya infection. In addition, the disease typically starts with high fever and abrupt onset of severe pain in the joints, which are not usually seen with rheumatoid arthritis," he explained.
Researchers at Washington University School of Medicine in St. Louis also found that blood tests of patients with the Chikungunya virus and those with rheumatoid arthritis can produce similar results. This may lead some patients with the virus to be misdiagnosed.
The findings, reported in the January issue of Arthritis and Rheumatology, underscore the need for doctors to obtain detailed travel and medical histories from patients being evaluated for rheumatoid arthritis. Such details could help distinguish between the two conditions.
"For now, good travel histories of patients are among the best diagnostic tools for physicians," said senior author Wayne Yokoyama, MD, the Sam and Audrey Loew Levin Professor of Medicine. "Recent travel to the Caribbean, Central and South America, Africa, India or other areas where the virus is prevalent should raise suspicions of Chikungunya infection. In addition, the disease typically starts with high fever and abrupt onset of severe pain in the joints, which are not usually seen with rheumatoid arthritis."
The global spread of the Chickungunya virus suggests that the disease is likely to be a diagnostic challenge in the years ahead. Physicians treat rheumatoid arthritis with drugs that suppress the immune system, but it's not yet known whether that approach will help or harm patients with Chikungunya virus.
The virus is spread by infected mosquitoes and first was identified 60 years ago in eastern Africa. Since then, it has spread to many parts of the world.
In 2014, more than 2,000 people in the United States developed the infection after traveling abroad, mostly to the Caribbean. That same year, the Centers for Disease Control and Prevention reported 11 cases of Chikungunya infection among people living in Florida who had not traveled outside the United States, suggesting that mosquitoes in that state were spreading the virus.
In most patients, the infection causes a fever, rash and severe joint pain in the hands, feet, knees, neck and elbows. The fever and rash typically subside in seven to 10 days, but symptoms of arthritis may persist for 12-15 months in up to 60 percent of patients. Some patients' symptoms persist for up to three years.
For the study, lead author Jonathan Miner, MD, PhD, a rheumatology fellow, studied 10 St. Louis-area residents who traveled in June 2014 to Haiti, where they were infected with Chikungunya virus. The patients were evaluated seven to 10 weeks after the onset of symptoms. During that time, eight patients developed persistent arthritis, several with joint pain so severe they had difficulty walking.
"All eight patients with Chikungunya-related arthritis met the American College of Rheumatology's criteria for a diagnosis of rheumatoid arthritis," Miner said. "Their recent travel to Haiti led us to suspect they had Chikungunya virus infections."
As a comparison, the study also included healthy subjects and patients newly diagnosed with rheumatoid arthritis who had not yet received treatment.
Laboratory tests that measured levels of specialized immune cells in the blood showed additional similarities between Chikungunya virus infection and rheumatoid arthritis, including elevated levels of specialized T cells, which suggest, despite the persistence of symptoms, that the immune system has recognized and is fighting the virus. These studies were performed on state-of-the-art instruments in the university's newly established Center for Human Immunology and Immunotherapy Programs.
To positively identify Chikungunya virus, the researchers performed highly specialized tests of the immune system, with results that showed antibodies against the Chikungunya virus in patients' blood. Such testing is only available at the CDC and in research laboratories.
According to Yokoyama, a Howard Hughes Medical Institute investigator, the similarities between Chikungunya virus infection and rheumatoid arthritis suggest that learning more about the virus may help scientists better understand rheumatoid arthritis, which affects about one in every 100 people worldwide.
Said co-author Deborah Lenschow, MD, PhD, associate professor of medicine and of pathology and immunology: "We're anticipating that Chikungunya virus will spread broadly in the United States, so it's important to develop better tools for diagnosis, prevention and treatment."
The researchers also have established a Chikungunya registry at chikv.dom.wustl.eduto build a database of cases for studying the virus in more detail.
What Causes Rheumatoid Arthritis?
Unlike osteoarthritis, a condition caused by wear and tear on joints,rheumatoid arthritis occurs when the immune system targets a person's joint linings. Rheumatoid arthritis is a chronic inflammatory condition that also affects other tissue, but the joints are usually the most severely affected.
Although doctors aren't sure of the exact cause of rheumatoid arthritis, it's thought that it may result from a combination of genetics and environmental triggers. Some researchers believe an infection with a bacteria or virus can trigger the development of rheumatoid arthritis in someone who's genetically susceptible. However, to date, no infection or organism has been identified as the cause.
As rheumatoid arthritis develops, some of the body's immune cells recognize one type of the person's own protein as a foreign intruder. The exact protein is unknown and may be one of any number of potential candidates. Some of them are produced in response to infection, such as a viral, bacterial, or fungal infection. Other possible proteins may have a genetic connection or stem from other causes.
Whatever the source, cells called lymphocytes react to this protein. The reaction then causes the release of cytokines, which are chemical messengers that trigger more inflammation and destruction. With rheumatoid arthritis, the main target of inflammation is the synovium, the thin membrane that lines the joints. The inflammation also spreads to other areas in the body, ultimately causing not onlyjoint damage but inflammation, chronic pain, fatigue, and loss of function.
The most significant cytokines in rheumatoid arthritis are tumor necrosis factor (TNF) and interleukin-1, both triggers of joint damage. Some treatments for rheumatoid arthritis block these cytokines, reducing inflammation and joint damage.
What Risk Factors Increase the Chance of Rheumatoid Arthritis?
Rheumatoid arthritis is more common in women than in men. In fact, 70% of the patients with rheumatoid arthritis are women. In addition, there's an increased risk of rheumatoid arthritis in women who have never been pregnant and in those who have recently given birth.
Rheumatoid arthritis has a genetic link, and the disease can run in families. People with specific human leukocyte antigen (HLA) genes have a greater chance of developing rheumatoid arthritis than people who do not have the HLA genes. Still, not everyone with the HLA genes develops rheumatoid arthritis. In other words, genes can increase the risk of rheumatoid arthritis, but other factors are also involved. For example, older age and cigarette smoking may increase the risk of getting rheumatoid arthritis.
Symptoms of rheumatoid arthritis include joint pain, swelling, stiffness, and fatigue -- which can be mild or severe. Doctors recommend treating rheumatoid arthritisearly, before there are visible signs of joint destruction.
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