1. What are the causes of ankylosing crestitis?
There is no clear answer as to how ankylosing crestitis occurs, although a large number of studies have found that its onset is mainly related to genetic, infectious, immune, environmental and traumatic, endocrine, and metabolic disorders.
The first is that ankylosing crestitis often occurs in more than 2 members of a family. The first-degree relatives of patients with ankylosing crestitis have a 20–40 times higher risk of developing the disease than the general population. If one of the monozygotic twin brothers and sisters has the disease, there is a 50% or greater chance that the other will develop it. In the past 20 years, a large number of studies have proven that the development of ankylosing crestitis and the human leukocyte antigen HLA-B27 are closely related, and the rate of HLA-B27 positivity in our normal population is 2% – 7%, while the rate of HLA-B27 positivity in patients with ankylosing crestitis is 91%. Other data show that the prevalence of ankylosing crestitis is about 0.1% in the general population, up to 4% in the family line of ankylosing crestitis patients, and up to 11% – 25% in the first-degree relatives of HLA-B27-positive ankylosing crestitis patients. These data suggest that HLA-B27 positive individuals, or those with a family history of ankylosing crestitis, have a significantly increased likelihood and risk of developing ankylosing crestitis.
Second, recent studies suggest that the development of the disease may be related to infection. Patients with ankylosing crestitis have a significantly higher frequency of K. pneumoniae infection in stool cultures than normal subjects (79% in the former and 30% in the latter). Serum levels of anti-Klebsiella pneumoniae antibodies were significantly higher in patients with ankylosing crepitus, with a positive rate of 43.3% compared to 4.4% in normal subjects. Using colonoscopy, inactive enterocolitis was found in 29% – 49% of patients with ankylosing crepitus, and the incidence of abnormal lesions was even higher when observed histologically. Salazosulfapyridine, which has anti-infective activity, has shown good efficacy in the treatment of ankylosing crestitis. All of these indicate that there is a relationship between intestinal infections and ankylosing crestitis.
2. Is ankylosing spondylitis hereditary?
If a parent has ankylosing crestitis and is HLA-B27 positive, the chance of passing on the HLA-B27 gene to the child is 50%. However, not everyone with the HLA-B27 gene will develop ankylosing crestitis. However, a report from the PLA General Hospital showed that a survey of five family lines with a family history of ankylosing crestitis found that of the 53 relatives surveyed However, a report from the PLA General Hospital showed that among the 53 relatives surveyed, there were 21 cases of ankylosing crestitis. Therefore, patients with ankylosing crestitis should be alert to the possibility of similar disease in their next generation. If their children have early symptoms of ankylosing crestitis, such as unnoticeable transient, asymmetric joint pain in the lower extremities, pain at the attachment points of tendons such as patellar tendon and Achilles tendon, stiffness and discomfort in the lower back, and recurrent iridocyclitis, they should be seen by a hospital with a rheumatology specialty in a timely manner. If the diagnosis is still doubtful, CT film of sacroiliac joint should be taken as early as possible to clarify the diagnosis and provide timely treatment.
3.What is the clinical significance of HLA-B27 testing in patients with ankylosing crestitis?
Although HLA-B27-positive patients may not necessarily develop ankylosing crestitis, and HLA-B27-negative patients may not necessarily not develop ankylosing crestitis, HLA-B27-positive tests have an important reference value for the diagnosis and prognosis of ankylosing crestitis.
It contributes to the diagnosis in the following ways.
(1) If the symptoms and signs suggest that the patient has crestal arthropathy, HLA-B27 positivity significantly increases the chances of a correct diagnosis.
(2) In children with inflammatory arthropathies, a positive HLA-B27 may indicate the possibility of ankylosing crestitis.
(3) HLA-B27 positivity in children of patients with ankylosing crestitis, especially in males, suggests a greater likelihood of developing ankylosing crestitis.
In addition, it was found that compared with HLA-B27-negative ankylosing crestitis, HLA-B27-positive individuals have relatively earlier onset, more severe clinical symptoms, higher incidence of systemic symptoms and peripheral arthritis (e.g., hip), more altered immunological indicators (increased ESR, CRP, and γ-globulin), and higher incidence of familial aggregation, bamboo-like crests, and ophthalmoplegia, i.e., HLA -B27-positive patients have a more severe disease and a poor prognosis. In conclusion, HLA-B27 is a reference indicator for the diagnosis of ankylosing crepitus and is not a basis for diagnosis. If the diagnosis of ankylosing spondylitis is confirmed by X-ray, HLA-B27 may not be performed again.
4.What are the typical symptoms of ankylosing spondylitis?
The typical symptoms of ankylosing crestitis include
(1) Low back pain. The pain is often vague and difficult to locate, and is often ignored by the patient. The symptoms are aggravated at night and at rest, and can be reduced after activity. If the thoracic spine is involved, chest pain and limited expansion of the chest may occur, and if the cervical spine is involved, the inability to lower the head, tilt back and difficulty in turning the neck from side to side may occur.
(2) Morning stiffness. Patients may experience stiffness of the low back in the early morning or when they are sedentary, and the symptoms may be relieved after light activity. Morning stiffness is often an early symptom of the patient and an indicator of the patient’s disease activity.
(3) In the late stage, as the whole crest becomes ankylosed from the bottom up, the patient’s crest movement is obviously limited, and he cannot bend his back, or even hunchback deformity and the whole crest is ankylosed, but most patients are only partially involved in the crest, or even limited to the sacroiliac joint lesion.
(4) Other symptoms. There is often weight loss in the early stage of the disease. Fatigue, fever and night sweats are often present during the active phase.
5.How to confirm the diagnosis of ankylosing crestitis?
If you have the typical symptoms of ankylosing spondylitis mentioned above, you should go to a hospital with a rheumatology department in time. The international diagnostic criteria used to diagnose ankylosing crestitis are the New York criteria established in 1966, which include: low back pain lasting at least 3 months, relieved by exercise; thoracic whistling and inspiratory mobility measured at the level of the 4th rib space less than 2,5 cm; limited movement in three directions of lumbar flexion, retroversion and lateral bending; plus a sacroiliac joint x-ray finding of one or both joint spaces blurring, narrowing or widening, jagged bone destruction, increased bone density, or loss of joint space, etc., then ankylosing crestitis can be diagnosed. This criterion is strict and cannot diagnose early ankylosing crestitis. In order to make an early diagnosis of ankylosing crestitis, a comprehensive clinical analysis should be made in conjunction with the patient’s family history, whether the patient is positive for HLA-B27, the presence of pain at the tendon end attachment site and CT examination of the sacroiliac joint. Patients with symptoms other than those typical of ankylosing crestitis, but not enough to confirm the diagnosis of ankylosing crestitis, can be diagnosed as “undifferentiated crestal arthropathy” according to the European Study Group on Crestal Arthropathy (ESSG) classification or Amor criteria (details of which will not be discussed further), and these patients should be followed up regularly. These patients should be followed up regularly and should be treated accordingly.
6. Why is it important to emphasize that patients with ankylosing crestitis should adhere to exercise therapy?
It is often found that patients with ankylosing crestitis stay in a state of inactivity or inactivity for a long time in order to reduce or avoid the pain of the affected joints, which leads to muscle atrophy or joint contracture, resulting in disability of the joints or limbs that were not serious and could have recovered. The correct approach is to receive anti-inflammatory medication to keep joint pain under control and to move the joint in a timely, careful and gradual manner. During the acute phase, gentle passive movement of the joint, to the extent that the joint pain has just appeared, once or twice a day, can help reduce joint contracture. When not exercising, the acutely inflamed joint should be placed in an appropriate position (functional position) or braked with a deck so that some more joint function can be maintained in the future in the event of unavoidable contracture or deformity that cannot be corrected. During the subacute and acute phases, crestal and extremity stretching exercises should be adhered to, which will both increase or maintain the range of motion of the joint and relieve pain caused by muscle spasm or tension. The number, duration, and frequency of daily activities should be gradually increased according to the pain tolerance level. Again, it is important to emphasize that adherence to exercise in all areas of ankylosing crestitis is as important as medication.
7. What kinds of physical activities are available for patients with ankylosing crestitis?
Many patients, including some doctors, overemphasize the importance of taking medication and neglect physical exercise. In fact, in order to achieve satisfactory results and maximize the mobility of the joints, the patient must be treated with medication along with the corresponding rehabilitation therapy.
Patients’ physical exercise should aim at the following three items.
(1) Maintain the mobility of the thorax.
(2) Maintain the flexibility of the crest.
(3) Maintain the motor function of the limbs, prevent or reduce muscle atrophy due to disuse, maintain bone density and strength, and prevent osteoporosis, etc.
The pathological basis of ankylosing crestitis is tendon attachment point inflammation. Fibrosis and ossification in these areas will affect the function of the body, and proactive and correct physical exercise will help maintain the normal function of the body. Do not be bedridden because of pain and unwilling to move, which will only accelerate the progress of the disease. The intensity of exercise depends on the specific condition, and it is generally believed that the pain should not last more than 2 hours after exercise. Do at least one set of deep whistling activities every day to help maintain the mobility of the thorax and improve lung capacity. Other more appropriate exercises are: jogging, swimming, playing tai chi, etc. When swimming, the body in the water in a flat position, buoyancy offset the effect of gravity, all the joints and muscles can be effective exercise, pay attention to should swim in as many ways as possible. It is best to avoid high-intensity strenuous sports, such as wrestling, playing tennis, basketball and table tennis. When playing sports, trainers with cushioning insoles should be worn to reduce trauma to the joints. Special emphasis should be placed on patients with hip joint lesions to insist on functional exercises for the hip joint, such as abduction and squatting, in order to maintain a good functional state of the joint and reduce the possibility of joint disability.
8.Does ankylosing crestitis affect the fertility of patients?
The disease itself does not adversely affect the reproductive organs and functions of the patient, regardless of whether the disease occurs in men or women. Women can have normal conception, pregnancy and delivery, and men can have normal insemination. However, the following two points should be noted.
(1) Inappropriate treatment with drugs that can affect reproductive function during the course of the disease, such as tretinoin or kombucha, which are commonly used in China, can lead to amenorrhea or infertility, so patients who want to have children in the early stages of the disease should avoid using such drugs. In addition, salazosulfapyridine can reduce sperm in men, leading to infertility, but this is reversible and can be restored after stopping the drug, and the drug does not affect hormone secretion in the body, nor does it cause chromosomal aberrations, so patients should not be too afraid and anxious, and those who want to have children can temporarily stop the drug to restore the number of sperm.
(2) Female patients in the advanced stage of the disease, if they have joint or crest deformities and cannot take care of themselves, the burden of pregnancy and childbirth on the patient will be immeasurable and should therefore be considered carefully.
9.Is ankylosing crestitis life threatening? Is it curable?
No, it is not life-threatening, but it cannot be cured. Ankylosing crestitis is a chronic disease that is benign and usually does not involve important organs, so it generally does not affect life expectancy. As long as treatment is carried out under the guidance of a rheumatologist, symptoms can be reduced or controlled, complications can be prevented, and physical fitness can be maximized for a healthy life.
There is no cure for this disease. However, by taking non-steroidal anti-inflammatory drugs can reduce pain, improve sleep and fatigue and other uncomfortable symptoms, and by taking slow-acting anti-rheumatic drugs that change the course of the disease can bring relief or slow down the progress of the disease. With appropriate functional exercise, patients in the early stages can recover well and continue their schooling or return to work; patients in the late stages can also minimize the occurrence of crestal deformities. Therefore, patients with ankylosing crestitis should actively receive treatment and adhere to appropriate functional exercises on the basis of medication. In this way, the patient’s joints will remain in good functional condition and the majority of patients will be able to live as normal.
Ankylosing crestitis affects each person differently. It is characterized by alternating spontaneous remissions and exacerbations, especially in the early stages of the disease. The prognosis is generally good because the lesions are often relatively mild or self-limiting, and most patients are able to work and study full time and survive as long as the general population, while a minority of patients may exhibit persistent disease activity and develop severe disability early in life. A poor prognosis is often suggested by the following factors: male age of onset ≤16 years; hip involvement; markedly elevated serum immunoglobulin IgA; failure to control pain symptoms after 2 weeks of heavy NSAID therapy; combination of extra-articular symptoms such as cardiovascular involvement, renal amyloidosis, crestal fracture, and other serious complications. Hip involvement and complete ankylosis of the cervical spine are important causes of functional impairment. In recent years, hip arthroplasty has improved the partial or total loss of function in these patients. In addition, early diagnosis and treatment of the disease can improve the prognosis, and early treatment can delay and postpone the development of the disease and greatly reduce the occurrence of crestal ankylosis. Therefore, patients suffering from ankylosing crestitis should pay sufficient attention to the disease, be confident, and actively cooperate with the doctor’s treatment.
10.Does ankylosing crestitis affect other joints besides the crest?
Although the crest is the main site of ankylosing crestitis, the incidence of joint lesions in the extremities is not uncommon. It has been shown that 43% of people have joint involvement of the extremities as their first symptom, and 24% to 75% of people have joint involvement of the extremities throughout the course of the disease, with some reports reaching 91%.
Ankylosing crestitis can affect any joint, but asymmetric involvement of the large joints of the lower extremities, such as the knee and ankle, is predominant, while small joints, such as the elbow, hand and foot, are rarely involved. Only one joint may be involved, or several joints may be involved. Early in the disease, both hip joints may be involved. The clinical manifestations are pain, swelling and limited movement of the joint. In most patients, the pain and swelling of the joint can be controlled with appropriate treatment, but repeated attacks may result in flexion contracture and eventual loss of function. In addition, inflammatory changes in the periarticular tissues may occur, including plantar pain due to plantar fasciitis, which may last for several weeks or longer, and Achilles tendinitis, which may present with redness, swelling, and pain in the heel area where the Achilles tendon attaches to the heel bone.