Leprosy

Introduction to leprosy Leprosy is a chronic contagious disease caused by M. leprae. It mainly invades human skin and nerves and can cause progressive and permanent damage to skin, nerves, limbs and eyes if left untreated. The prevalence of leprosy has a long history and is widely distributed, bringing serious disasters to the people in the epidemic areas. To control and eliminate leprosy, we must adhere to the principle of prevention first, implement the principle of active prevention and control, control infection, and implement the practice of investigating, separating, and treating, actively discovering and controlling infectious diseases, cutting off Infectious routes, while improving the immunity of the surrounding natural population, inoculation of BCG vaccine to children in the epidemic areas, family members of the patients, and close contacts with negative poliomycin and tuberculin, or effective chemotherapy for prophylactic treatment . basic knowledge The proportion of illness: 0.002%, contagious Susceptible people: no special people Mode of infection: contact spread Complications: peripheral nerve injury

Cause of leprosy

Pathogenic bacteria infection (35%):

The pathogen is M. leprae. Under the optical microscope, the intact bacilli are straight rods or slightly curved, about 2 to 6 microns long, about 0.2 to 0.6 microns long, without flagella, spores or capsules. The distribution of leprosy in patients (as an example of a tumor-type end) is more common, mainly found in certain cells of the reticuloendothelial system such as skin, mucous membranes, peripheral nerves, lymph nodes, liver and spleen. The skin is mainly distributed in nerve endings, macrophages, smooth muscles, hair bands and blood vessel walls.

Infection with pathogen carriers (30%):

1. Direct contact with infection This method is a direct contact between a healthy person and a contagious leprosy patient. The infection is caused by contact between the skin or mucous membrane containing M. leprae and the damaged skin or mucous membrane of a healthy person. This infection is most common in family members who are in close contact with the patient. Although the closeness of exposure is related to the onset of infection, this does not rule out the possibility of occasional contact and infection. 2. Indirect contact with infection is a form in which healthy people and infectious leprosy patients are infected through certain media. For example, contact with clothes, bedding, hand towels, food utensils, etc. used by infected patients. The possibility of indirect contact with infection is less than the probability of direct contact with infection, but it cannot be ignored.

Leprosy prevention

To control and eliminate leprosy, we must adhere to the principle of prevention first, implement the principle of active prevention and control, control infection, and implement the practice of investigating, segregating, and treating, discovering and controlling infectious diseases, and cutting off infection. Ways, giving regular drug treatment, while improving the immunity of the surrounding natural population, can effectively control infection and eliminate leprosy. In view of the current prevention of leprosy, lack of effective preventive vaccines and ideal preventive drugs, In the method, various methods should be used to detect patients early, and the patients should be given timely combined regular chemical treatments, and close contacts of children in the endemic areas, family members, and polio and tuberculin reactions. , can be given BCG vaccination, or given effective chemotherapy for preventive treatment.

Leprosy complications Complications peripheral nerve injury

Leprosy is a chronic contagious disease caused by M. leprae. It mainly invades human skin and nerves. If it is not treated, it can cause progressive and permanent damage to skin, nerves, limbs and eyes. Therefore, its clinical complications are mainly caused by nerve skin and nerve damage. Clinically, the most serious and serious complication of leprosy is deformity and disability, followed by numbness, deformation, muscle atrophy and loss of temperature and pain.

Symptoms of leprosy Common symptoms Facial skin has nodular hyperplasia Muscle atrophy Tactile dysfunction Congestive dysfunction Spotted nodule Joint pain Aching body Discomfort Nasal septum perforation

After the leprosy invades the body, it is generally considered that the incubation period is 2 to 5 years on average, and the short period is several months. The elderly are more than ten years. If the disease occurs, most of them are unconscious. Before the typical symptoms begin, some people often have general malaise. Muscle and joint pain, limb sensation abnormalities and other systemic forequarters symptoms, these performances are not specific, immune system is stronger, develop to the end of tuberculosis-like leprosy, low immunity or defects, develop to the tumor type end, now according to level 5 Classification, the characteristics of various types of leprosy symptoms are as follows:

First, tuberculosis-like leprosy

This type of patient has strong immunity, M. leprae is confined to the skin and nerves, skin damage has rash and plaque, the number is often one, two, the edges are neat, clear, often have obvious feelings (wet, pain, touch The distribution of obstacles is asymmetrical, and the bristles of the lesions fall off. This is a very important feature. It occurs in the vulnerable parts of the limbs, face, shoulders and arms. The color of the rash is light and reddish. No scales, the color of the plaque is often dark red, the outline is clear, the edges are inclined upwards, and the edges are moved to the flattened atrophy center, and some tend to have a semi-annular, circular or arched shape with different edge thicknesses. Dry and scaly, sometimes visible damage caused by the accumulation of most small papules, the large cutaneous nerve can be touched near the damage, sometimes the nearby lymph nodes become larger, and the eyebrows generally do not fall off.

After the peripheral nerve of this type is involved (such as auricular nerve, ulnar nerve, sacral nerve, etc.), the nerve rod becomes coarse and fusiform, nodular or beaded, hard and tender, mostly unilateral, severe Due to delayed type hypersensitivity reaction, abscess or fistula can be formed. Some patients have neurological symptoms without skin damage, which is called pure neuritis. The clinical manifestations of nerve enlargement, skin sensory disturbance and muscle weakness in the corresponding parts, severe neurological involvement At the time of neurological nutrition, exercise and other functional disorders, large and small intermuscular muscles and interosseous muscle atrophy occur, forming a "claw hand" (ulnar nerve involvement), "hand rubbing" (median nerve involvement), "drift wrist" (Nerve involvement, "ulcer", "rabbit eye" (face nerve involvement), "finger (toe) bone resorption" and other manifestations, deformity occurred earlier.

This type of bacteria is generally negative, the leprosy test is strongly positive, the bacterial immune function is normal or near normal, and the histopathological changes are tuberculous granuloma, which is characterized by no "infiltration zone" under the epidermis, acid-fast staining. Can not find acid-fast bacilli, a small number of patients can be self-healing without treatment, if the treatment subsides faster, the general prognosis is good, but the deformity is often difficult to recover.

Second, the boundary line of tuberculosis-like leprosy

This type of tuberculosis is similar to tuberculosis, with spotted plaques and plaques, reddish color, purple or brownish yellow, well-defined borders, and some blank areas or drilling areas in the center of plaques (also known as Infiltrating area, immunization area), forming a ring-shaped damage with clear inner and outer edges. The skin inside the hole area seems normal, the damage surface is mostly smooth, and some have a small scale, and the damage is frequent, the size is different, and some are scattered. The trunk, limbs, and face are many, widely distributed, but asymmetrical, although there are sensory disturbances, but lighter and later than TT, the eyelashes generally do not fall off, the nerves are thick and asymmetrical, not as rigid and irregular as TT, mucosa Lymph nodes, testes, eyes and internal organs are less affected and lighter.

This type of bacteria is generally positive, cell density index (logarithmic classification, the same) 1 ~ 3 +, leprosy test is weakly positive, suspicious or negative, cellular immune function test is lower than normal, histopathological changes and TT is similar, but the lymphocytes around the epithelioid cells are less, looser, and there is a narrow "no infiltration zone" under the epidermis. The section is resistant to acid staining or has a little leprosy. The prevention is generally better, "upgrade response" Variable TT, "degraded reaction" can be changed to BB, leprosy reaction is easy to cause deformity and disability.

Third, the middle line of leprosy

This type of skin lesions are characterized by pleomorphism and pleochroism. The rash has rash, plaque, infiltration, etc. The colors are wine color, dry yellow, brown yellow, red, tan, etc., sometimes on a piece of skin lesion. It has two colors, the edge part is clear, the part is unclear, and the damage form is banded, serpentine or irregular. If it is strip-shaped, one side is clear, one side is infiltrated, if it is plaque, the center There is a drilling zone, the inner ring is clearly raised, gradually slanting outward, the outer edge is infiltrated and unclear, and has an inverted dish appearance, and some of the damage is red or white, ring-shaped or multi-ring, shaped like a target or The badge is called target spot and badge spot. Some patients have facial bat-like bat-like wings, color grayish brown, called bat-like face, and there is a tumor on the skin of different parts of a patient. Type and tuberculosis-like damage, sometimes seen as "satellite" damage, and some patients in the elbow, the extension of the knee and the hip can be composed of thick padded pieces of nodules, damage the surface slip, touch the Soft, the number of damage is large, the size is different, the distribution is wide, the asymmetry is more, God After damage, mild numbness, lighter than tuberculoid, lepromatous weight ratio, often does not fall off imminent, mucous membranes, lymph nodes, eyes, testes, and may be visceral involvement.

This type of bacteria is positive, the bacterial density index is 2~4+, the leprosy test is negative, the cell immune function test is between the two poles, the histopathological changes are tissue cell granuloma, and the subcutaneous "no infiltration zone" is large. Partially existed, it can be seen that the tissue cells differentiate into epithelial-like cells to varying degrees, generally small, and some of the sections can be seen in typical, atypical foam cells, with few lymphocytes dispersed, and the slices are more resistant to Mycobacterium staining, prognosis. Between the two poles, this type is the most unstable, the "upgrade response" to BT, and the "downgrade response" to BL.

Fourth, the boundary type of tumor-like leprosy

This type of skin damage has rash, papules, nodules, plaques and diffuse infiltration. The damage is mostly tumor-like damage, the number is large, the shape is small, the boundary is unclear, the surface is bright, and the color is red or orange. It is widely distributed and has a tendency to be symmetrical. The sensory obstacles in the damage are lighter, appear later, and some damage is greater. The center is a drilling area, the inner edge is clear, the outside is infiltrated, the eyebrows, the eyelashes, and the hair can fall off. , often asymmetrical, in the late stage, the deep diffuse infiltration of the face can also form a "lion face", the mucosa congestion, infiltration, swelling, lymph node and testicular swelling in the middle and late stage patients have tenderness, nerve involvement tends to be multiple bilateral It is more uniform, softer to touch, and deformed later.

This type of bacteria is strongly positive, the bacterial density index is 4-5+, the leprosy reaction is negative, the cellular immune function test shows defects, histopathological changes, the granuloma nature tends to foam cell granuloma, and some tissue cells develop into Atypical epithelioid cells, some develop into foam cells, lymphocytes often appear in the form of foci, exist in the infiltration of foam cells, the pathological features of this type, the section of acid-fast staining has a large amount of leprosy, the prognosis is better than LL, It is worse than TT, but it is still unstable. The "upgrade reaction" can be changed to BB, and the "degraded reaction" can be changed to LL.

Fifth, tumor type leprosy

This type of patient lacks immunity to M. leprae. The leprosy passes through the lymph and the blood spreads throughout the body. Therefore, the range of tissue and organ invasion is relatively wide. The characteristics of skin damage are many, widely distributed and symmetrical, and the edges are blurred and tend to merge. The surface is greasy and smooth, except for the light spots, the color of the skin mostly develops from red to yellowish yellow and brownish yellow. The sensory obstacle is very light. In the early stage, the eyelashes are sparse, and the skin begins to fall off from the outside of the eyebrow. Eyelashes are also sparse, this is a clinical feature of lepromatous leprosy, strong positive for leprosy inspection, skin lesions with rash, infiltration, nodules and diffuse damage, early plaque lesions distributed throughout the body, to the face, chest The back is more common, the color is reddish or light, the border is unclear, and it must be carefully examined under good light to be able to recognize. Later, in addition to the continued increase of the plaque loss, the formation of shallowness and diffuseness Nodules, the face is diffuse and thickened due to infiltration, the appearance is mildly swollen, and the eyebrows often fall off. Later, the lesions merge into a large infiltration, or in the lesion and diffuse infiltration. Nodules appear, diffuse infiltration develops deeper, more obvious and serious, often throughout the body, diffuse thickening in the face, deeper skin lines, hypertrophy of the nose and lips, enlargement of the earlobe, eyebrow discoloration, hair thinning or large pieces falling off, knot The knot is deeply mixed with the sexual infiltration, and the conjunctiva is congested to form a "lion face"-like appearance. The extremities of the extremities, the shoulders, the back, the buttocks, the scrotum, etc. have many nodules of different sizes, and later, due to the pervasive Sexual damage is partially absorbed, and there is obvious sensory disturbance and sweating. In the calf, the skin is slightly hardened, smooth and shiny, and there is fish scale or snake skin-like damage. It will not retreat for a long time, and some hair will be almost stripped, showing more residual hair. Distribution along the blood vessels.

Although the nerve trunk is involved, the sensory disturbance is mild, the performance is later, the nerve trunk is slightly thick, symmetrical and soft, and muscle atrophy, deformity and disability can also occur in the late stage.

Nasal mucosal damage occurs earlier, first congestion and swelling, and later, as the condition worsens, nodules, infiltration and ulcers occur. In severe cases, there may be nasal septum perforation. When the nasal bridge collapses, the saddle nose is seen. The lymph nodes are affected at an early stage, and the swelling is mild. Large, often not noticed by people, in the middle and late stages, it is swollen and obvious, and there is tenderness.

Testicular involvement, first atrophy and atrophy, and tenderness, breast enlargement.

Eye involvement, conjunctivitis, keratitis, iridocyclitis, etc., visceral tissue and organ involvement, such as hepatosplenomegaly.

This type of strong positive bacteria, 4 ~ 6 +, negative leprosy test, cell immune function test showed obvious defects, histopathological changes characterized by foam cell granuloma structure, mainly composed of cytoplasm-rich typical foam cells, epidermis There is no "infiltration zone", and there are a large number of leprosy strains in acid-fast staining. It can be bundled or into a ball. Early treatment has a good prognosis, less deformity, and can be disabled in the late stage. This type is relatively stable, and only a few are in certain conditions. The next can be changed to BL.

Sixth, undetermined leprosy

This class is the early manifestation of leprosy. It is primary, not included in the five-level classification. It is unstable in nature and can be self-resolved or transformed into other types. It evolves into what type depends on the strength of the patient's body immunity. Type change, most of the evolution to tuberculosis, a few to the boundary line and tumor type evolution, the clinical symptoms are light, do not involve the internal organs, skin lesions are simple, there are pale erythema or light spots, the surface is flat without infiltration, no shrinkage, The hair can be detached, the skin lesions are round, elliptical or irregular, the edges are clear or partially unclear, the distribution is asymmetrical, the skin lesions may have mild sensory disturbances, the nerve trunks are lightly affected, although the increase is but the hardness Lower, less dyskinesias and deformities, more negative for the bacteria, more positive for the leprosy test, normal or near normal for the cellular immune function test, some obvious defects, histopathological changes for non-specific inflammatory cell infiltration The prognosis depends on the degree of cellular immune development of the body. The leprosy test is positive, and the normal cell immune function test has a good prognosis. Some of the developments can be self-healing, some to other types. Evolution.

Leprosy check

First, the physical examination should be comprehensive, check the whole body skin, nerves and lymph nodes under natural light.

Second, when examining the nerve, it is necessary to pay attention to the changes of the peripheral nerve trunk, but also to pay attention to changes in sensory and motor function. Peripheral nerve trunk examination: general attention to the ear nerve, ulnar nerve and phrenic nerve, others such as supraorbital nerve, anterior cervical nerve , supraclavicular nerve, middle nerve, phrenic nerve, superficial peroneal nerve, posterior tibial nerve and cutaneous nerve around and under the skin lesion, should pay attention to its hardness, thickness, nodules, abscess and tenderness, etc. Functional examination is to determine the condition that the nerve is not slightly affected, and it is divided into subjective examination and objective examination.

Subjective sensory test

The order of skin dysfunction is generally first lost temperature (cold heat sensation), second loss of pain sensation, and finally loss of touch. When inspecting, the patient should first be informed of the examination method, conduct a teaching test, and then check: cold and thermal sensation, Two tubes of the same size can be used, divided into cold water and hot water (50 ° C), first tested on healthy skin, then alternated in the two lesions at the skin lesions, without a certain order of contact with the skin, so that the patient can answer whether the hot and cold is correct, pain Check that you can use a pin or a sewing needle to puncture the healthy skin first, then prick the skin lesions, and test the pain disappearance or dullness; the tactile examination can be used to gently touch the skin with the cotton wool of the wool or cotton swab, so that the patient can immediately point out the touch by hand. The site is tested for loss of touch or dullness.

2. Objective test method

1 histamine test: 0.1 ml of 1/1000 aqueous solution of histamine phosphate was injected into the skin of healthy skin and skin lesions. After about 20 seconds, it was normal to have a erythema of 10 mm in diameter and then 40 seconds. The bell, another red spot with a diameter of 30-40 mm around the original erythema, the edge of the erythema is diffuse, called secondary erythema, and finally a wheal is formed in the center of the erythema. If there is no secondary erythema, it is abnormal. This method is used for the examination of light spots and white spots.

2 pilocarpine test (sweating test): select normal skin and skin lesions, respectively, apply iodine, after drying, inject 0.1 ml of 1/1000 pilocarpine solution in two places, immediately sprinkle a thin layer of starch on it, about After 3 to 5 minutes, the normal skin sweats and the starch immediately turns blue-violet. If it does not sweat, the starch does not change color.

3 vertical muscle function test: with 1:100,000 picric acid nicotine solution 0.1 ml, respectively, injected into the skin of skin lesions and healthy skin, such as nerve endings normal, the vertical muscle contraction of chicken skin phenomenon, otherwise, no chicken skin phenomenon.

3. Motor dysfunction check

During the examination, let the patient lift the amount, frown, drumsticks, whistle, toothy and other movements, observe whether the facial nerve is paralyzed, let the patient flex and extend the wrist, internal and external exhibition fingers, finger pointing, palm grip, etc., observe the nerve function of the upper limb, Let the patient do the back extension, plantar flexion, varus, valgus and other movements to observe whether the phrenic nerve is paralyzed.

Third, leprosy inspection

Mainly from the skin and mucous membranes, if necessary, can be used for lymph node puncture, skin investigation: select active, skin damage, disinfection of the skin, wear disinfectant gloves when checking, use the left thumb, eat two fingers to pinch the patient's skin Lift tightly, make the local skin white, then cut a 5 mm long, 3 mm deep incision with a right hand, and scrape the tissue fluid with a knife blade, apply it on the slide, fix the acid-resistant stain, microscopic examination, incision cotton ball Pressing, the number of parts to be taken depends on the needs.

Fourth, histopathological examination

The diagnosis, classification and efficacy judgment of leprosy are of great significance. The active damage should be selected, and the fat layer should be deep. If the damage is different, two samples should be taken at the same time. This is the diagnosis of the leprosy. Value.

The leprosy test is a simple method for determining the resistance of the body to M. leprae. It can partially reflect the strength and presence of the body's immune response to M. leprae. The type of leprosy is crude leprosy. , pure bacillus and leprosy, the current general is crude leprosy (also known as intact leprosy).

Test method and result judgment: 0.1 ml of crude leproscin was injected intradermally into the flexor of the forearm to form a white bulge with a diameter of about 6 to 8 mm. The reaction results were observed later. Early reaction: 48 hours after injection, the judgment result was observed. Those with invasive erythema larger than 20 mm were strongly positive (), those with 15 to 20 mm were moderately positive (), those with 10 to 15 mm were weakly positive (+), and those with 5 to 10 mm were suspicious (±) ), 5 mm or less or non-responder negative (-); late reaction: 21 days of injection observation observation results, red invasive nodules occurred at the injection site and were strongly positive (), the nodule infiltration diameter was greater than 5 mm were moderately positive, nodular infiltration of 3 to 5 mm in diameter was weakly positive (+), mild nodular infiltration was considered to be suspicious (±) in patients below 3 mm, and local non-responder was negative (-).

Diagnosis and diagnosis of leprosy

diagnosis

The diagnosis of leprosy must be meticulous, strive for early diagnosis, no missed diagnosis, no misdiagnosis, early treatment and early recovery, no time to make the condition worse, cause deformity, disability, or enlarge the infection, diagnosis based mainly on medical history, clinical symptoms, bacterial examination and The results of histopathology and other examinations, comprehensive analysis, concluded that for individual cases that are difficult to be diagnosed at one time, they can be reviewed and followed up regularly, or consulted with relevant departments for exclusion or diagnosis.

First, the medical history inquiry must focus on the items related to leprosy, such as whether it is from the epidemic area, family, relatives and neighbors have the same patient, and have no contact history.

Second, the physical examination should be comprehensive, check the whole body skin, nerves and lymph nodes under natural light.

When examining the nerve, pay attention to changes in the peripheral nerve trunk, and pay attention to changes in sensory and motor function.

Differential diagnosis

In the differential diagnosis, it is necessary to grasp the characteristics of leprosy lesions. The skin lesions are often accompanied by sensory disturbances. The peripheral nerve trunks are often coarse. The leprosy bacteria are often detected in the lesions of tumor-type leprosy. When these characteristics are distinguished from other diseases, in general In the case, it can be identified.

Need to identify the skin disease: tumor type leprosy should be associated with skin kala-azar, neurofibroma, alopecia areata, nodular xanthoma, ichthyosis, rosacea, seborrheic dermatitis, nodular erythema, dermatomyositis, etc.: tuberculosis The type of leprosy should be differentiated from sarcoidosis, ring erythema, persistent erythema erythema, skin black fever, light plaque, ring granuloma, vulgaris vulgaris, body palsy, telecentric erythema, etc.; undetermined leprosy should be associated with vitiligo. Anemia, skin black fever, light-spot type, light-spotted type and tinea versicolor, etc. Identification: The boundary type leprosy should be differentiated from lupus erythematosus, skin kala-azar, mycosis fungoides (infiltration period).

Neuropathy to be identified: syringomyelia, polyneuritis caused by other causes, traumatic peripheral nerve injury, progressive spinal muscular atrophy, progressive proliferative interstitial neuritis, progressive muscular dystrophy, lateral femoral Derma neuritis, facial nerve paralysis and so on.

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