Kidney damage in leptospirosis
Introduction
Introduction to renal damage in leptospirosis Leptospirosis is an acute systemic infectious disease caused by pathogenic Leptospira. In the middle of the disease, damage and dysfunction of various organs often occur. In severe cases, severe liver and kidney failure can occur, thereby jeopardizing The life of the patient. basic knowledge The proportion of illness: 0.002% Susceptible people: no specific population Mode of transmission: insect-borne transmission of digestive tract Complications: typhoid jaundice, renal failure
Cause
Causes of renal damage in leptospirosis
(1) Causes of the disease
The pathogen Leptospira (abbreviated as leptospira) is the main cause of this disease. The hook has 12 to 18 spirals in shape, hooks at both ends, and is active in rotational motion. It has strong penetrating ability and hook. The body can grow slowly under the condition of aerobic conditions in rabbit serum medium, but if it is inoculated into sensitive animals (such as guinea pig and golden hamster), the positive rate can be significantly increased, and it can survive for 1 to 3 months under suitable conditions in vitro. It is very sensitive to cold, dry and general disinfectants. At present, leptospira are mainly classified according to serological reactions. There are 18 groups of 70 types in China. In recent years, monoclonal antibody technology using leptospira has been carried out in China for classification. The initial identification of the hook and body identification has also achieved initial success.
After invading the human body through the skin, the hook body can reproduce through the lymphatic system or directly into the blood circulation, and produce toxins, which cause systemic toxic symptoms. The invading hooks are widely distributed in the internal organs of the human body, but the hooks are present in the organs. The amount of damage is not completely consistent with the degree of organ damage. The hook body itself has no direct pathogenic effect, and the interaction between the leptin toxin and the organ tissue is the main cause of tissue damage and capillary damage. The development of the important organs has a serious disorder.
For example, hemorrhagic leptospirosis is caused by a decrease in prothrombin or platelets, but is associated with capillary damage caused by vascular endothelial injury. Pathological examinations such as vascular endothelial swelling and sarcoplasmic reticulum expansion , mitochondria enlargement, the initial reaction of these endothelial cell necrosis can occur in all organs, suggesting that endothelial function and permeability changes have occurred before endothelial necrosis, parenchymal hepatocyte necrosis and inflammatory response are mild, suggesting that the liver The dysfunction is caused by the disorder of enzyme function at the subcellular level of hepatocytes. In the study of experimental acute renal failure, it is found that there are obvious ischemia or toxin damage to the kidney, which is hooked with patients with this disease. Somatic sepsis is associated with an infection-associated regulatory mechanism that enhances the response of the body to local infections, and suggests that the leptospira are one of the pro-nephrotic pathogens.
The transmembrane potential difference between the luminal side of the renal tubule and the medial surface of the epithelial cells, the permeability of water and sodium and potassium were determined by renal microinfusion technique. It was found that these indicators were abnormal in the leptospirosis model animals, but when vasopressin was added After returning to normal, suggesting that the renal tubular urinary concentrating function of leptospirosis-related nephropathy is abnormal, except for the proximal renal tubular sodium reabsorption disorder, the medullary part of the collecting tube is less reactive to vasopressin and leads to a decrease in water permeability. May be also an important reason.
(two) pathogenesis
In recent years, a new viewpoint has been put forward on the pathogenesis of leptospirosis. It is believed that when the leptospira enters the human body, it is phagocytized by macrophages and dissolves, releasing a glycoprotein component, namely leptospira toxin, which inhibits Na-K-ATPase. The role of this cell level is closely related to the clinical electrolyte imbalance, arrhythmia and diarrhea in leptospirosis. It is suggested that Na-K-ATPase is a specific target of the toxin, because it is a leptoid. The glycoprotein component has the same affinity and inhibition for each Na-K-ATPase isomer.
Recently, it has been found that lipid peroxidation of cell membrane plays an important role in the occurrence of vascular disease of leptospirosis. It is also suggested that some components of the outer membrane of renal tubular epithelial cells may directly participate in the induction and maintenance of leptospirosis. The immune mechanism of glomerulonephritis.
Prevention
Prevention of renal damage in leptospirosis
Carry out mass comprehensive preventive measures, rodent control and vaccination are the key to controlling the outbreak of leptospirosis and reducing the incidence.
1. Epidemic monitoring Due to the continuous expansion of new epidemic areas, the monitoring of rodent density, rodent virus rate and susceptible population should be done in the south, and pig manure management should be done in the north to prevent rainy season or flood season from pig manure. Urine spillover caused widespread spread. The incidence and prevalence in most parts of China occur mostly in the rainy and warm summer and autumn. Humans are generally susceptible to hooks.
2. Eliminate and manage the source of infection, and carry out the campaign to eliminate rodents and protect the disease. In combination with the "two pipes (water, manure), five reforms (water wells, toilets, livestock pens, stoves, environment)" work, especially the management of pig manure and urine manure should be advocated to prevent pollution of water sources, rice fields, ponds and rivers. purpose.
3, cut off the route of transmission, combined with industrial and agricultural production to transform the source of the epidemic, flood control and drainage. Protect water and food and prevent urine pollution from rats and sick animals. Avoid swimming, splashing, and wading in epidemic areas in popular areas and popular seasons. Put rice in the field before harvesting rice, or put pesticide treatment to strengthen personal protection and skin coating protective drugs.
4. Make food hygiene and personal hygiene to prevent rodent excreta from contaminating food, without touching the rodents and their excrement. Animals should be prevented from being bitten by large and small mice. Most rural areas in China have the habit of raising pigs. They should avoid close contact between humans and animals, and pay attention to personal hygiene to prevent infection.
5. Enhance personal immunity. Residents, troops in the affected areas, and those who participate in harvesting, flood control, and drainage may be in contact with the infected water. Inoculate the multivalent vaccine of the same type of hooks as the epidemic strains in the region as soon as possible. Patients with heart, kidney disease, tuberculosis and fever are not given an injection.
6, drug prevention for high-risk susceptible people such as pregnant women, children and adolescents, the elderly or laboratory workers accidentally contact with the hook, suspected of infection of the disease but no obvious symptoms, can be injected penicillin daily 80 ~ 1.2 million U, continuous 2 ~3 days. In addition, it is also possible to use soil glutinous rice 30g, Houttuynia cordata 15~30g, andrographis, honeysuckle and other boiled water suits according to local conditions, or take Chinese medicine "Puji disinfection drink" addition and subtraction.
Complication
Renal damage complications of leptospirosis Complications, typhoid, jaundice, renal failure
The clinical manifestations of this disease can be divided into influenza typhoid type, pulmonary hemorrhage type, jaundice type, renal failure type and meningoencephalitis type, among which pulmonary hemorrhage type can be divided into common pulmonary hemorrhage type and diffuse type of hemorrhage. The condition is dangerous and the mortality rate is high. According to the clinical classification, the main complications are high fever, meningoencephalitis, jaundice, hemorrhage, acidosis and renal failure.
Symptom
Symptoms of renal damage in leptospirosis Common symptoms Conjunctival hyperemia, urinary anuria, proteinuria, hyperthermia, lymphadenopathy, urinary and renal damage, diffuse hemorrhagic muscle pain
The incubation period of leptospirosis is 1 to 2 weeks, up to 4 weeks, and fever can occur early, muscle pain (especially gastrocnemius pain and tenderness), general malaise, conjunctival hyperemia and lymphadenopathy, which are characteristic. Three symptoms", "three signs" infection poisoning performance, patients often have symptoms of organ damage in the course of 3 to 10 days, according to different clinical manifestations can be divided into influenza typhoid type, pulmonary hemorrhage type, jaundice bleeding type, renal failure type And meningoencephalitis type, etc., which can be divided into common pulmonary hemorrhage type and diffuse diffuse type of lung, the latter is dangerous and has a high mortality rate.
Leptospirosis-related nephropathy can be associated with influenza typhoid type, jaundice hemorrhagic leptospirosis, if it occurs alone, it is a type of renal failure, clinical manifestations mainly oliguria, proteinuria, a small amount of white blood cells in the urine, red blood cells, cast Etc., a small number of serious patients with progressive aggravation, the emergence of anuria, acidosis, renal failure, uremia, leptospirosis-related nephropathy generally good prognosis, most patients recover through oliguria, polyuria.
Examine
Examination of renal damage in leptospirosis
1. routine inspection
(1) blood routine: white blood cells are mild to moderately elevated, mostly (10 ~ 20) × 109 / L, jaundice bleeding type can be as high as 60 × 109 / L, neutrophils can account for 80% ~ 95%, ESR Increased, BUN in the blood increased when the kidney was damaged, and Scr increased.
(2) Urine routine: There may be a small amount of protein, red blood cells, white blood cells and casts in the early urine.
(3) Blood biochemistry: When renal failure occurs, the patient's serum potassium and blood sodium are lower than normal. Some patients have lower serum potassium and sodium levels than patients with acute tubular necrosis. The reason may be related to the excretion of adrenal cortex hormones. related.
2. Specific diagnostic test
(1) Condensation test (microscopic agglutination test): The live bacteria of the standard strain of Leptospirosis are used as antigens, mixed with the patient's serum and observed under a microscope. If specific antibodies are present, agglutination can be seen. This test has specificity. Sexuality is the most commonly used test for the diagnosis of this disease. It is usually positive and gradually increased 7-8 days after the disease. Its titer is more than 1:400 or the serum serum titer is more than 4 times. .
(2) Enzyme-linked immunosorbent assay (ELISA): The method is highly specific and positive and more sensitive than the positive test, and the conditional areas are worth promoting.
(3) Monoclonal antibody (McAb): The production of a leptoid group-specific or type-specific McAb by hybridoma technology is superior to the conventional routine immunodiagnostic serum products in terms of specificity and sensitivity, and the production volume is large. Easy to standardize, it is a valuable and promising specific diagnostic method.
Diagnosis
Diagnosis and diagnosis of renal damage in leptospirosis
Diagnostic criteria
In recent years, the performance of leptospirosis has been divided into two-phase course.
1. "Heptospirosis" phase high fever, conjunctival congestion, myalgia and headache, then hepatitis, nephritis and bleeding.
2. Symptoms such as fever in the initial stage of "immune" gradually disappear, and symptoms of the central and peripheral nervous system appear.
After the third day of the "three symptoms" and "three signs", the patient may have severe jaundice and renal failure. At this time, the disease should be suspected, and the diagnosis depends mainly on specific diagnostic tests.
For example, in epidemic areas, there are epidemiological data such as exposure to epidemic water during the epidemic season. The clinical manifestations of the patients are early three symptoms and three signs (fever, myalgia, general malaise and conjunctival hyperemia, gastrocnemius tenderness, lymphadenopathy). More prominent symptoms of the big tenderness, multiple organ damage in the middle, mainly jaundice, hemorrhage and ARF, laboratory tests for increased white blood cells, urinary abnormalities and renal dysfunction, a specific diagnostic test can confirm the diagnosis of the disease.
Differential diagnosis
1. Severe viral hepatitis Severe hepatitis may have deep jaundice, bleeding tendency, renal dysfunction (hepatic and renal syndrome), easy to be confused with leptospirosis, in addition to the characteristics of epidemiology, the main identification points are:
(1) Different forms of onset, severe liver infection and mild symptoms of digestive system, rare conjunctival hyperemia, swollen lymph nodes, no tenderness of the gastrocnemius.
(2) The progression of severe liver disease is relatively slow.
(3) Compared with patients with leptospirosis, ARF in patients with severe liver disease appears later, rarely occurs within 1 week, and renal failure is often the dying stage of patients with severe liver disease.
(4) The degree of liver function damage of severe liver is directly proportional to the degree of jaundice and also to the weight of the hook.
(5) Hepatitis virus marker examination and specific diagnostic test of leptospirosis, which is of decisive significance for the identification of the two.
2. Epidemic hemorrhagic fever has chills, fever, hemorrhage and kidney damage. About 20% of patients have gastrocnemius pain and tenderness, which is similar to leptospirosis, but epidemic hemorrhagic fever often has prominent head, eyelid and back pain. , face, neck, chest congestion, conjunctival and oral mucosa congestion, edema, skin mucous membrane sputum, chest, underarm sputum point sputum, the symptoms worsened after fever, jaundice is rare, urine often has membrane, serum A specific test can be performed to determine the corresponding specific antibody.
3. Acute glomerulonephritis clinically has edema, hematuria, proteinuria, red urine, white blood cells and casts, often can cause renal damage, severe cases of azotemia, but no obvious fever, no hook Symptoms of early infection with body disease and other clinical features such as bleeding, jaundice, etc.
4. Acute pyelonephritis, sepsis, acute hemolytic anemia, etc., can be expressed as fever and kidney damage, should be differentiated from leptospirosis.
