Allergies and fever Rash arthralgia
Introduction
Introduction Systemic allergy and fever rash joint pain, also known as acute allergic reaction triad, is the clinical manifestation of acute drug-induced interstitial nephritis. That is, the patient has systemic allergic reactions and fever, rash, joint pain and the like. It is characterized by erythematous rash and systemic allergic reaction. An allergic reaction is a reaction that occurs when an immune body is stimulated again by the same substance. The reaction is characterized by rapid onset, strong reaction, and rapid regression; generally does not destroy tissue cells, and does not cause tissue damage, and has obvious genetic predisposition and individual differences. Systemic allergic reactions refer to the presence of allergic symptoms in more than 2 organs. It is a serious allergic reaction.
Cause
Cause
1. The occurrence of toxic nephropathy may be related to the following factors:
(1) Antibiotics for nephrotoxicity: such as amphotericin B, neomycin, cephalosporin II, etc. have direct nephrotoxic effects, while penicillin G, cephalosporin (IV, VI), etc. may cause kidney due to allergies. damage.
(2) Age and renal function status: In elderly patients and original kidney patients, the incidence of nephrotoxicity is significantly higher and more serious.
(3) Changes in effective blood volume and renal blood flow: When the blood volume decreases and the renal blood flow decreases, the renal toxicity of the antibiotic is more likely to occur.
(4) The degree of infectious diseases and electrolyte imbalance: When the patient's infection is severe or even toxic shock or electrolyte imbalance, the antibiotic nephrotoxicity increases.
(5) Liver function status of the patient: Some antibiotics can be detoxified by the liver and then excreted by the kidney. When the liver function declines, the burden on the kidney is aggravated, and nephrotoxicity occurs.
2. Antibiotics that often cause ATN include the following categories:
(1) Aminoglycoside antibiotics: These antibiotics have high nephrotoxicity and are most likely to cause ATN, including kanamycin, gentamicin, amikacin, tobramycin, neomycin and streptomycin.
(2) -lactam antibiotics: penicillins have no obvious nephrotoxicity and do not cause ATN. The first generation of cephalosporin has different degrees of nephrotoxicity, especially cefotaxime, followed by cefotaxime and cefazolin.
(3) Sulfonamides: such as sulfathiazole and sulfadiazine can cause: 1 crystal nephropathy, especially in oliguria or urine pH <5.5, its crystal blockage of renal tubules can cause ATN; 2 hemoglobinuria: can make G6PD Intravascular hemolysis occurs in children with defects, resulting in hemoglobinuria.
(4) Other antibiotics: such as amphotericin B, polymyxin, vancomycin, etc. also have obvious nephrotoxicity, can cause ATN.
Examine
an examination
Related inspection
Allergen detector Cerebrospinal fluid Calcium urine routine blood analyzer for the detection of hepatitis A virus antigen (HAVAg)
1. There is no uniform standard for the clinical diagnosis of acute allergic interstitial nephritis. In the case of gross hematuria and acute allergic reactions such as fever, rash and joint pain, and acute renal failure of unknown cause, the possibility of acute allergic interstitial nephritis should be considered.
In 1980, Laberke et al proposed that acute allergic interstitial nephritis syndrome should have systemic manifestations of fever, rash, eosinophilia, hematuria, decreased renal function, anemia, etc.; based on comprehensive analysis of relevant literature, drug allergic interstitial The clinical diagnosis of nephritis is usually:
1 has a history of use of allergic drugs;
2 systemic allergic reaction, often drug eruption, drug fever and peripheral blood eosinophilia;
3 abnormal urine test: aseptic leukocyte urine (including eosinophilic urine) may be associated with leukocyte cast, microscopic hematuria or gross hematuria, mild to severe proteinuria (often mild proteinuria);
4 in the short term, progressive renal dysfunction; proximal and/or distal renal tubular functional damage and glomerular dysfunction, renal glucosuria and low osmotic pressure;
5 related antibodies, such as anti-diphenylmethoxypenicillin hapten antibodies, are detected in the blood circulation of the patient;
6 re-exposure to this class of drugs again;
7 along the TBM visible complement C3 sedimentation;
8B shows that the kidneys are normal or enlarged.
Anyone with the above 12 and 3 and/or 4 or 5 may not be diagnosed with a clinical diagnosis of renal biopsy.
However, clinical practice has found that many cases of allergic interstitial nephritis (AIN) lack the most critical systemic allergic reactions, which makes it difficult to diagnose clinically. For suspected cases with recent medication history, unexplained ARF occurs, especially when renal glucosuria and urinary protein are not much, the disease should be suspected, and renal biopsy should be performed in time to understand the type and extent of interstitial damage. Develop a treatment plan and determine the prognosis. The diagnosis of atypical cases must rely on renal biopsy pathological examination, and the diagnosis can only be established if the pathological findings are consistent with the drug allergic AIN.
Drug-specific lymphocyte transformation tests help to identify pathogenic drugs. The test is a blood sampling in vitro, safe and reliable, and no harm to patients. The principle is to apply a specific antigen of the drug in in vitro culture to stimulate the sensitized lymphocytes of the patient to cause transformation. According to the level of lymphocyte response to drug antigens, to determine whether it is allergic to this drug. It has high specificity and is rarely false positive, but negative results cannot rule out the possibility of drug allergy.
2. Diagnosis of nephrotoxicity damage of aminoglycoside antibiotics: It should be closely observed after administration, so as to detect nephrotoxic damage early, the sooner it is discovered, the sooner the drug is stopped, the faster and better the renal damage will be recovered. The following items are helpful for early diagnosis:
1 observe changes in urine volume, early detection of oliguria, oliguria, no urine;
2 closely monitor urine routine (red blood cells, white blood cells, protein, etc.), urine sediment to check cell casts;
3 monitoring lysozyme, alkaline phosphatase, -glutamyl transpeptidase, N-acetyl--glucosaminidase and isoenzyme, blood, urine 2 microglobulin, etc., if there is a significant increase, To stop the drug observation;
4 Determination of the urine GGT / Cr ratio, if the ratio is three times more than the base value, it is valuable;
5 follow-up observation of changes in renal function, such as unexplained blood urea nitrogen, elevated creatinine, it is necessary to consider drug-induced renal damage;
6 Digital imaging analysis method can detect the nephrotoxicity of aminoglycoside antibiotics earlier than azotemia.
7 In animal experiments, renal tissue immunohistochemistry found that excessive expression of "Heat shock protein 47" (HSP47) is an important marker of gentamicin nephrotoxicity. Kidney biopsy can be performed clinically when necessary to detect HSP47 protein, which is helpful for early diagnosis of renal damage.
Diagnosis
Differential diagnosis
The erythematous rash: is a very common symptom of skin diseases, many skin diseases have this symptom.
Systemic allergic reaction: An allergic reaction is the reaction of an immune body that is stimulated by the same substance. The reaction is characterized by rapid onset, strong reaction, and rapid regression; generally does not destroy tissue cells, and does not cause tissue damage, and has obvious genetic predisposition and individual differences. Systemic allergic reactions refer to the presence of allergic symptoms in more than 2 organs. It is a serious allergic reaction.
