Pine caterpillar osteoarthropathy

Introduction to pine caterpillar osteoarthrosis Pine caterpillar osteoarthrosis refers to osteoarthrosis caused by direct or indirect contact with pine caterpillars, corpses or insects, and is part of systemic diseases. The disease is prevalent in southern provinces such as Fujian, Guangdong, Hubei, Hunan, and Zhejiang. Mostly in the summer and autumn, when the pine caterpillars are released from April to August, there is a regional outbreak. According to the survey, about 40 species of pine caterpillars have been found in China, and there are six species that are more harmful and widely distributed: red pine caterpillar, oil pine caterpillar, larch caterpillar, horsetail pine caterpillar, Yunnan pine caterpillar, and caterpillar pine caterpillar. Among them, Dendrolimus punctatus has the widest distribution and the greatest harm. basic knowledge The proportion of illness: 0.005% Susceptible people: no special people Mode of infection: non-infectious Complications: osteoarthritis edema erythema swelling

The cause of pine caterpillar osteoarthrosis

Pine caterpillar osteoarthrosis refers to osteoarthrosis caused by direct or indirect contact with pine caterpillars, corpses or insects, and is part of systemic diseases.

Pine caterpillars generally have 6 ages, and the first to second stage pine caterpillars are not long-stained, the third to fourth stages of venom are not developed, and the 5-6 stage pine caterpillar venom and venom cells are well developed. It is a period of disease. In this period, the chest of the pine caterpillar has developed hollow venomous hair. Each fang of the venom has venom gland cells, which secrete venom into the venous lumen. When the pine caterpillar is adult, the venom is established on the worm. Outside the shell, the insects are also highly pathogenic, and even if the dead insects fall on the ground or in the water, they are very susceptible to disease.

During the season of pine caterpillars, such as cutting wood in the worm area, cutting grass or cutting rice in polluted paddy fields, it is exposed to pine caterpillars, corpses, poisonous hair or contaminated clothing, firewood, water, etc. It has been confirmed by epidemiological investigation and animal experiment research institute, so it is named as pine caterpillar disease. The toxins secreted by pine caterpillar venom and venom gland cells enter the human body after contact with the skin, which can cause allergic immune inflammatory reaction, mainly infringement. Skin and bone joints, sometimes the eyes and auricles can also be affected.

The mechanism of the disease has not yet been clarified. Some scholars believe that after the poisonous burrs enter the skin of the human body, the toxins enter the blood circulation, causing toxemia, but the animal experiments have not been confirmed, and because of the early detection of the disease, the anti-allergic drugs can be quickly controlled. The condition, so some scholars infer that the mechanism of the disease is allergic, but it has not been strongly confirmed. Some scholars believe that it is caused by infection. Because of the purulent liquid extracted from the diseased joint or skin induration, it has been cultured. Staphylococcus aureus, Staphylococcus aureus, Pseudomonas aeruginosa, etc., the pathological findings are consistent with low toxicity infections, but most of the locally extracted liquid cultures are negative, and all of the above views fail to suggest a clear pathogenesis of the disease. Further research is needed in the future.

Prevention of pine caterpillar osteoarthrosis

Pine caterpillar joint disease is a common disease caused by pine caterpillars and their pollutants. It is more common in the southern provinces of China. It is more common in summer and autumn, and the common parts of the body such as hands, feet, wrists, and ankles are common. At the site, the human body is exposed to pine caterpillars and their pollutants for several hours to several days after the symptoms appear. The dermatitis is mainly rash, wind swell, swelling when the joint is involved, the pain is severe, and the dysfunction is obvious. The patient should seek medical treatment promptly. Allergies, anti-inflammatory and analgesic drugs, generally good effect, severe joint swelling, severe pain, chronic period of joint stiffness and deformity can be treated by synovectomy, joint debridement or arthrodesis to restore joint function, the disease, to prevent The Lord, if entering the forest, should strengthen personal protection to avoid direct contact with pine caterpillars and their pollutants. After contact with pine caterpillars, they should be washed immediately with soapy water or 3% ammonia to relieve symptoms.

Complications of pine caterpillar osteoarthrosis Complications osteoarthritis edema erythema swelling

The early stage of the disease mainly manifests as dermatitis and osteoarthritis, local itch accompanied by burning sensation, followed by edema erythema, maculopapular rash or wheal, occasionally blisters, pustules, red bumps, after 1-2 weeks of dermatitis, Secondary affected joints are swollen, reddened, severely painful, limited in activity, and patients with long course of disease have bone changes. The bones are firstly loose, the trabecular bones are blurred, and then the edges of the bones are blurred. Or worm-like, severe cases can be seen in the joint space stenosis, articular surface destruction, if the treatment is not appropriate, the condition often delays for months or years, seriously affecting joint function, and even disabled.

Symptoms of pine caterpillar osteoarthritis common symptoms acne rash skin itching subcutaneous hematoma weakness

1. The patient with this disease has a sudden onset of nighttime within two days after the contact history, and can also be delayed to 15 to 30 days. The disease is characterized by mild systemic symptoms and partial local manifestations. There may be no or lighter systemic symptoms. Have chills, poor appetite, dizziness, headache, general malaise or accompanied by body temperature below 38 °, occasionally up to 39 °, usually 2 to 3 days later improved or regressed, regional lymph nodes can be swollen, gradually subsided in about half a month More than not broken.

2, local symptoms in the body exposed parts, often in the hands, wrists, feet, sputum, etc., after the bone and joint involvement, acute joint swelling, local red, pain, high skin temperature and dysfunction, severe pain, Sustained stabbing and paroxysmal intensification, more severe at night, difficult to fall asleep, redness and swelling can be repeated, with a single joint incidence is more common, but about one-third of the violation of multiple joints, can also show a joint symptom subsided After that, another joint has developed disease. Most patients have a blush with a diameter of 1 to 2 cm. The center can have a painful nodular mass. In some cases, the swollen nodules may have a sense of fluctuation, and the puncture may have a viscous bloody secretion. No bacterial growth, if the lesion is chronic, it can be gradually stiffened, a small number of patients can have difficult sinus and fistula, and even septic arthritis.

3, when the bones and joints involved in the onset, may also be associated with various skin manifestations of skin invasion, such as maculopapular rash, wind rash, blisters and pus, subcutaneous nodules, subcutaneous hematoma, red lumps, etc. After treatment, Often within a week, the rash is cured, a few can form chronic dermatitis for several months, but also scleritis, acute iridocyclitis, auricular inflammation, etc., sometimes accompanied by a painful soft tissue mass, gradually increasing, the peak period is 15 to 30 days, then soften, the course of disease is about 1 to 3 months.

4, pine caterpillar osteoarthrosis, high incidence, high risk, often left dysfunction, and even varying degrees of disability, and some diseases can be as long as 1 to 2 years.

The above various types of clinical manifestations may occur individually or in two or more of the same patient's body, but more commonly it is osteoarthritis, accounting for 30% to 90%.

Examination of pine caterpillar osteoarthrosis

The auxiliary examination methods for this disease are mainly laboratory tests and X-ray examinations:

1. Laboratory inspection :

More than 60% of patients have eosinophilia in the blood, 50% to 60% of patients have a total white blood cell count of more than 10,000/mm3, and erythrocyte sedimentation rate is about 40% to 70%. Soft tissue mass or joint puncture fluid is often pale yellow or Green and yellow viscous gelatinous fluid, occasionally bloody, bacterial culture is mostly negative, a small number of Staphylococcus aureus or Staphylococcus aureus or Pseudomonas aeruginosa growth.

2, X-ray inspection :

(1) In the acute phase, it is mostly negative. Most of the bone changes can be seen about one month after the onset. About 12 days after onset, the X-ray film can show the soft tissue swelling around the joint, the subcutaneous fat transparency is reduced, and the joint cyst is enlarged. In a few cases, calcification and ossification occur in adjacent soft tissues, early osteoporosis, and then the edges of the bone are blurred, causing worm-like destruction. It is common in tendons, ligaments attached to the bulge, such as the trochanter of the femur, the olecranon The styloid process of the humerus, in most cases, has a single thin strip of periosteal reaction in the bone destruction area, and some are bone-like or lace-like.

(2) Chronicity is mainly caused by hyperplasia of the small bone destruction area, forming a small ring lesion with clear edge and hardening. The involvement of small tubular bone is thickening of the whole backbone. If the epiphysis or metaphysis is damaged, the sacral line may be involved. ; caused early fusion of the epiphysis, there is no manifestation of dead bone formation in bone changes.

(3) joint changes in addition to early manifestations of swelling shadows and osteoporosis, visible joint gap asymmetry narrow, cartilage surface uneven, deformation, sometimes visible subluxation, bone destruction often under the cartilage, chronic lesions are mainly bone Hyperplasia and sclerosis, the possibility of self-integration of the joints, the formation of joint rigidity.

Diagnosis and identification of pine caterpillar osteoarthrosis

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