Pine caterpillar disease osteoarthritis

Introduction to pine caterpillar disease Pine caterpillar disease is a disease discovered in the 1970s. It is a direct or indirect contact with pine caterpillars. The short is several hours. In the elderly for several days, local dermatitis and joint swelling and pain occur. The light is usually within a few days. Healing, severe cases can last for several years, and permanent bone and joint damage can occur, with varying degrees of joint dysfunction. Exposures such as wrists and feet are most common. basic knowledge The proportion of illness: 0.005% Susceptible people: no special people Mode of infection: non-infectious Complications: elbow joint rigidity

The cause of osteoporosis osteoarthrosis

(1) Causes of the disease

The cause is unknown, but the incidence is closely related to the contact with pine caterpillars. The season of good hair is from June to July and from October to November every year. It is consistent with the life history of adult caterpillars of two generations of pine caterpillars, and the affected parts are mostly exposed parts of the body. All cases are mainly local symptoms, so it is generally believed that the cause of the disease is caused by the human body contacting the venom of the pine caterpillar thoracic section and the toxin contamination in the infected gland cells.

(two) pathogenesis

The pathogenesis is still not very clear. There are currently three inferences: 1 poisoning, pine caterpillar hair puncturing into human skin, toxins entering the blood circulation, causing toxemia and tissue reaction around the joint; 2 allergic reaction; 3 infection, pathology of the disease There are few materials, and there is no definitive conclusion. According to the pathological materials made after a small amount of local lesion resection, the synovial membrane of the joint has different degrees of thickening, vascular proliferation, swelling of endothelial cells, abundant lymphocytes, plasma cells and a small amount of fascination. Acidic granulocyte infiltration, active fibroblast proliferation and focal bone formation, localized bone destruction and hyperplasia at the end of the bone, joints with varying degrees of fiber rigidity and bony rigidity, and joint fluid smear and necrotic tissue No bacteria were found in the culture, and the pathological changes were similar to rheumatoid arthritis, suggesting that the pathogenesis of this disease is related to allergic reactions.

Pine caterpillar disease prevention of osteoarthrosis

Prevention should avoid direct contact with pine caterpillars and their contaminants; treatment should be washed immediately with soapy water, grass gray water, or with light ammonia water, with anti-allergic drugs, and keep the affected limbs rested after contact with pine caterpillars.

To publicize the knowledge to the masses so that they understand that the disease is directly or indirectly in contact with pine caterpillars, bones and joints caused by worms or insects. It is a local manifestation of systemic diseases, venom and venom cells in pine caterpillars. The toxins in contact with the skin or enter the human body can cause allergic immune inflammatory reactions to invade the skin and bones, causing pain or even lifelong disability for the patients. Therefore, people in high-risk areas should wear long-sleeved clothes or when they are working or going out. Trousers, to avoid skin exposure, contact with pine caterpillars, should be washed with soapy water immediately after contact, or coated with ammonia, not only can prevent the disease, but also neutralize toxins and relieve pain.

Pine caterpillar disease osteoarthrosis complications Complications elbow joint rigidity

Late stage may be complicated by joint dysfunction, joint deformity and rigidity, and local uplift caused by bone hypertrophy.

Pine caterpillar osteoarthrosis symptoms Common symptoms Joint swelling and pain ESR increased soft tissue swelling blister leukocytosis Skin itching

It is characterized by local swelling and pain, occasionally leukocytosis, increased erythrocyte sedimentation rate, and generally no systemic symptoms.

1. Acute phase: Within 1 month after onset, after exposure to pine caterpillar for several hours or several days, local symptoms of dermatitis appear, swelling of soft tissue around the joint, itching, swelling, pain, brightening or small blisters, usually recovered within a few days. In severe cases, the soft tissue around the joints is swollen, and the skin is purple-red, accompanied by severe acupuncture-like jumping pain, especially at night, sometimes with a small amount of exudate in the joints.

2. Subacute phase: 1 to 6 months after onset, the soft tissue swelling around the joint is relieved, but gradually hardens. The bone and joint lesions may occur after the local symptoms have been alleviated, and there may be joint dysfunction.

3. Chronic phase: After half a year of onset, it usually lasts for 2 to 3 years. The soft tissue around the joint is still swollen, but it is mainly hard, and the pain is relieved, but it can be intermittent.

Examination of osteoporosis osteoarthrosis

There are no special abnormalities in the laboratory tests.

An X-ray film can be selected for the examination of the disease, and the X-ray film is expressed as follows.

1. Acute phase: The soft tissue swelling around the joint is early change, the soft tissue level is blurred, and when it is severe, there may be a reticular dense shadow, the joint cyst is enlarged, and the density is increased.

2. Subacute phase: The soft tissue around the joint is swollen, the joint cyst is enlarged, the local density is increased, and the osteoporosis is only seen at the bone end at the beginning. Later, it can develop into general osteoporosis and bone destruction, which has certain characteristics.

(1) Bone destruction at the end of the bone: occurs on one or both sides of the bone end, which is characterized by a single or multiple small round worm-like lesions with clear edges, or shallow bone defects, with multiple Common, there is no reactive bone hyperplasia around, the articular surface is intact, at the top of the tibial metaphysis, below the epiphysis, there may be a wedge-shaped bone defect with the tip pointing to the central axis of the long bone.

(2) Joint destruction: the destruction of the edge of the subchondral joint surface is blurred. If the epiphysis does not heal, the destruction zone may occur inside the ankle, the articular cartilage is destroyed, and the joint space is narrowed.

(3) Bone end and joint destruction: bone ends and joints are simultaneously damaged, and joint dislocation or subluxation may be combined.

(4) Destruction of the bone protuberance attached to the tendon: manifested as local soft tissue swelling, accompanied by marginal single or multiple small sharp circular perforated bone destruction areas, commonly found in the upper and lower parts of the calcaneal nodules, humerus Upper and lower and tibial trochanter.

Periosteal hyperplasia is layered or lace-like, common in the phalanx, and there are small pieces, agglomerates or small strips of calcification in the soft tissue adjacent to the bone destruction zone.

3. Chronic phase

(1) Local soft tissue swelling of the joint persists.

(2) The bone destruction zone stopped developing and slowly repaired. The surrounding bone cancellously hardened and showed a small translucent shadow with dense edges. It is a characteristic manifestation of the chronic phase, the cortical bone is irregularly thickened, and the trabecular bone is sparse and disordered.

4. Late stage: hypertrophy of the bone end, nodular protrusion, the most prominent in the humerus and calcaneal nodules, the joint space is narrowed, and the joint deflection, subluxation and joint rigidity, generally mostly fiber rigidity.

Diagnosis and identification of osteoarthrosis osteoarthrosis

diagnosis

The disease is easier to diagnose based on medical history, signs and X-ray findings.

Differential diagnosis

1. Joint tuberculosis: Insidious onset, good invasion of large joints, no local redness.

2. Rheumatoid arthritis: The onset is insidious, the joints are symmetric and swollen, with morning stiffness.

3. Suppurative osteomyelitis: acute bone destruction in the acute phase, irregular edge, and the formation of dead bone, accompanied by periosteal hyperplasia, the formation of the capsule, and severe systemic symptoms, chronic bone hyperplasia and obvious hardening, death Bone or bone pupil, no small circular shadow with hardened edges.

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