Serum anti-streptococcal IgA,IgG and IgM antibodies in IgA-associated diseases

Serum anti-streptolysin-O antibody (ASO) and anti-streptococcal polysaccharide antibody (ASP) of IgA, IgG and IgM classes were measured using an enzyme-linked immunosorbent assay in 41 children with IgA nephropathy (Group A), 15 children with uncomplicated anaphylactoid purpura (Group B) and 13 children with purpura nephritis (Group C). The serum concentrations of the IgA, IgG and IgM classes were measured by single radial immunodiffusion. When compared with sex- and age-matched controls, the concentrations of serum IgA (but not of IgG or IgM) were significantly increased in the three groups studied. The titers of ASO of the IgA and IgM classes, and those of ASP of the IgA and IgG classes, were significantly increased in Group A. In Group B, only the ASP titers of the IgA class were significantly increased. No significant difference was noted in the titers of either ASO or ASP of any class in Group C. Thus, increased antibody response in IgA nephropathy is not restricted to IgA. Anaphylactoid purpura with or without renal disease appears to be different in its humoral anti-streptococcal response from IgA nephropathy.     

Immune complexes and Pseudomonas aeruginosa antibodies in cystic fibrosis.

Serum samples from 57 patients with cystic fibrosis were tested for the presence of IgG, IgA, IgM, IgE, and circulating immune complexes containing IgG, IgA, and IgM. Titres of class specific antibodies to Pseudomonas aeruginosa, and class specific antibodies to Ps aeruginosa in circulating immune complexes, were also measured. According to the Shwachman score the patients were divided into three clinical groups: group 1-moderate and severe disease, group 2-mild disease, and group 3-well. The results of the immunological investigations were correlated with the clinical state of the patients as assessed by the Shwachman score. Serum concentrations of IgG, IgA, and IgM were inversely correlated with the Shwachman score, but the differences between the groups were only significant for IgG and IgA. The same correlations were found for circulating immune complexes containing IgG and IgA. Antibodies to Ps aeruginosa could be detected in most of the patients'' serum samples. IgA antibody specific to Ps aeruginosa was the most often raised, even in patients in group 3. It is therefore suggested that IgA antibody specific to Ps aeruginosa could be an early marker of colonisation by Ps aeruginosa and a sensitive measurement of infection with Ps aeruginosa in young children with cystic fibrosis. Moreover, in the circulating immune complexes, class specific antibodies to Ps aeruginosa were found in nearly half the patients. The highest titres of IgG and IgA antibodies specific to Ps aeruginosa in the circulating immune complexes were detected in the patients with the worst clinical state (group 1).     

小儿包虫病免疫球蛋白及IgG亚类抗体检测的诊断价值探讨

目的　研究小儿包虫病的免疫诊断方法 ,探索其抗体应答阴性反应原因。方法　采用间接ELISA和单克隆双抗体夹心ELISA方法 ,对 1998年 5月至 2 0 0 2年 5月新疆自治区人民医院普外科 5 5例小儿包虫病患儿血清的IgG及亚类IgG1、IgG2 、IgG3 、IgG4和IgA、IgM、IgE类抗体及抗原和循环免疫复合物 (CIC)进行检测。 结果　 8种抗体检查方法中IgG1亚型抗体检测的敏感性和特异性最好 ;15例IgG抗体阴性患儿中 ,有 12例分别检测出IgG亚类和 (或 )IgM、IgA、IgE ,有 3例患儿血清各种抗体均呈阴性反应 ;患儿IgM抗体阳性率高于成人 ;IgG1分别与其它种抗体联合检测 ,以IgG1 IgA IgM检出率最高 ;IgG阴性小儿患者血清的循环抗原和CIC阳性率分别为 4 0 %及 2 6 6 7%。结论　IgG1 IgA IgM抗体联合检测方法可提高小儿包虫病免疫诊断的敏感性。抗包虫总IgG抗体表达水平低下、抗体表达种类不同及CIC的形成 ,是造成包虫病患儿IgG抗体反应阴性的主要原因     

Partially restricted antitoxins of tetanus and diphtheria in man.

Antibodies of restricted specificity have been identified in the human in response to certain antigens. The present study analyzed tetanus and diphtheria antitoxins isolated from selected human sera and suggested a restricted response in antibody production to each of these antigens. Purified antibodies from eight serum specimens with elevated hemagglutination titers to tetanus and four to diphtheria yielded only IgG proteins in concentrations of 160-500 microgram/ml. Although some of the tetanus specimens were derived from cord sera and tetanus immunoglobulin, none of the total group had antibodies of the IgA and IgM classes. Utilizing immunoelectrophoresis against heavy chain subclasses, genetic markers, and kappa and lambda quantitations, a predeliction for the kappa IgG1 subclass was established for both tetanus and diphtheria antibodies. The lambda light chains were present in diminished quantities, IgG2 heavy chains were absent, and the IgG3 and IgG4 chains were variably identified.     

Anti-rotavirus antibody in cerebrospinal fluid.

Ten infants with benign convulsions associated with rotavirus gastroenteritis had no specific antibodies in cerebrospinal fluid by enzyme linked immunosorbent assay (ELISA). On the other hand, eight of 173 patients with other neurological diseases had specific IgG, IgA, or IgM antibodies. The reason for positive ELISA results is discussed.     

Lack of correlation between infection with reovirus 3 and extrahepatic biliary atresia or neonatal hepatitis

Infection with reovirus 3 (Reo-3) has been suggested as the cause of extrahepatic biliary atresia and idiopathic neonatal hepatitis, but confirmation has been lacking. Therefore we have searched for a specific anti-Reo-3 antibody response in the sera of patients with biliary atresia or neonatal hepatitis and for Reo-3 antigens in their hepatobiliary tissues. Sera from 23 infants with extrahepatic biliary atresia, 12 with neonatal hepatitis, 30 age-matched control patients with other liver diseases, and 55 control patients without liver disease were tested by an enzyme-linked immunosorbent assay for total (IgA, IgG, and IgM) anti-Reo-3 antibodies; sera of infants younger than 6 months of age were tested also for IgM anti-Reo-3 antibodies alone. There was no difference between either total or IgM anti-Reo-3 antibody levels in infants with extrahepatic biliary atresia or neonatal hepatitis and levels in control infants. Reo-3 antigens were not detected in the hepatobiliary tissues of 19 infants (18 with biliary atresia, one with neonatal hepatitis) by an immunoperoxidase method that readily demonstrated Reo-3 in control infected HEp-G2 cells. Our data do not support a relationship between neonatal liver diseases and infection with Reo-3.     

Altered antibody isotype in cystic fibrosis: impaired natural antibody response to polysaccharide antigens

Patients with cystic fibrosis (CF) have impaired natural (preinfection) IgG2 antibody responses to Pseudomonas aeruginosa lipopolysaccharide. To investigate the basis for this defect, we measured natural IgG and IgG1-4 antibody levels to Haemophilus influenzae type b polyribophosphate (PRP) and tetanus toxoid by enzyme-linked immunosorbent assay in 24 adult CF patients and 20 normal controls. Immunoglobulin heavy- and light-chain allotypes were determined on 146 Caucasian CF patients and 96 controls. The tetanus toxoid-specific IgG response was predominantly IgG1. CF and control subjects had similar IgG and IgG1 antibody levels. The PRP-specific IgG response was predominantly IgG2. In contrast to tetanus toxoid results, CF patients had lower geometric mean level of PRP-specific IgG compared to normal controls (p = 0.0036). ELISA results were confirmed by liquid-phase 3H-PRP-binding assay: CF patients had a geometric mean serum antibody level of 395 versus 922 ng/ml in controls (p = 0.0044). PRP-specific IgG2 levels were also depressed in CF patients (p = 0.03). CF patients had a lower prevalence of the A2m(2) allotype than the local racially matched control sample (p less than 0.025). Other allotype prevalences including G2m(n) and Km(1) were similar. Impaired IgG2 antibody responses to microbial polysaccharide surface antigens in CF patients might predispose them to persistent endobronchial infection and lead to production of nonopsonizing isotype responses. The potential role of A2m(2), coded for in the H chain locus on chromosome 14, is unknown, but could be related to mucosal IgA2 antibody responses.     

Probable false positive coccidioidal serologic results in patients with cystic fibrosis

Coccidioidomycosis is an acquired fungal infection that afflicts primarily the respiratory tract. Cystic fibrosis patients who are being treated with glucocorticoids and immunosuppressed organ recipients may be at risk for infection with Coccidiodes immitis or reactivation of latent infection. The diagnosis is best made by demonstration of the organism in pathologic specimens or by culture. Serologic screening is another method that is reliable in most patients. We studied 98 patients who had serologic screening for Coccidiodes immitis performed as part of their evaluation for lung transplantation. This study revealed that approximately 15% of the cystic fibrosis patients screened had putative coccidioidal IgM, in the absence of an IgG response. None of the patients studied had a positive fungal culture for the organism. None of the non-cystic fibrosis patients screened had detectable coccidioidal IgG or IgM. We hypothesize that cystic fibrosis patients may have hyperimmune sera which interferes with serologic screening tests. We would recommend repeat serologic testing and attempts to identify the organism in tissue or by culture to confirm the diagnosis in these patients.     

Antibodies to staphylococcal teichoic acid and alpha toxin in patients with cystic fibrosis

Enzyme-linked immunosorbent assay (ELISA) was used for IgG antibody determination to teichoic acid and alpha-toxin from Staphylococcus aureus in 65 patients with cystic fibrosis (CF). In patients chronically colonized with S. aureus, elevated titres to teichoic acid were found in 13/35 (37%) patients, to alpha-toxin in 12/35 (34%) and to either antigen in 18/35 (51%). Patients with elevated titres to teichoic acid had a significantly lower X-ray score than patients with normal titres. The highest titres against both teichoic acid and alpha-toxin were seen in patients not receiving optimal treatment. These findings suggest that staphylococci contribute to the tissue damage in CF and that the determination of antibodies especially to staphylococcal teichoic acid might be of value in the diagnosis and management of staphylococcal infections in patients with CF.     

Immunological studies in cystic fibrosis

Evidence is presented to support the concept that much of the allergy in cystic fibrosis (CF) is IgE mediated. Total IgE levels were higher in allergic than in nonallergic CF patients. Levels were also higher in those patients who had had the greatest number of chest infections in the preceding 12 months. IgE antibody levels to Dermatophagoides pteronyssinus, Timothy grass pollen, and Aspergillus fumigatus were higher in those with positive results from skin tests to these allergens. The serum IgG, IgM, and IgA levels of allergic and nonallergic CF patients did not differ but the overall mean values for IgG and IgM were higher than those reported for healthy British children. The highest levels tended to be present in patients with the greatest number of recent major chest infections and the difference was significant for IgG. 16 patients had IgA levels 72SD below the reported means for age-matched controls and 11 of these were nonallergic. IgA levels were also higher in patients who had recently experienced major chest infections. 45 of the patients were tissue types for HLA A and B antigens but no significant clinical associations with single antigens were observed. The antigen phenotype A1 + B8 was more common in datients with multiple allergic symptoms than in those with a single allergy or merely a positive result from a skin test Nonsignificant increases of W19 in patients with frequent infections and of A2 in patients presenting with meconium ileus were also noted. The data presented do not permit a choice to be made between the alternative concepts of allergy as a primary abnormality in CF, and allergy arising secondary to infection.     

Detection of IgA and IgG but not IgE antibody to respiratory syncytial virus in nasal washes and sera from infants with wheezing

BACKGROUND AND OBJECTIVE: The capacity of respiratory syncytial virus (RSV) to stimulate an IgE antibody response and enhance the development of atopy and asthma remains controversial. Nasal washes and sera from 40 infants (20 with wheezing, 9 with rhinitis, and 11 without respiratory tract symptoms) were obtained to measure IgE, IgA, and IgG antibody to the immunodominant, F and G, virion proteins from RSV. STUDY DESIGN: Children (aged 6 weeks to 2 years) were enrolled in the emergency department during the mid-winter months and seen at follow-up when they were asymptomatic. All nasal washes were tested for RSV antigen. Determinations of antibody isotypes (IgE, IgA, and IgG) to RSV antigens were done in nasal washes and sera by using an enzyme-linked immunosorbent assay. In a subset of nasal washes, IgE to RSV was also evaluated by using a monoclonal anti-F(c)E antibody-based assay. RESULTS: Fifteen patients with wheezing, two with rhinitis, and one control subject tested positive for RSV antigen at enrollment. Thirteen patients with wheezing were <6 months old, and most (77%) were experiencing their first attack. Among the children with positive test results for RSV antigen, an increase in both nasal wash and serum IgA antibody to RSV-F(a) and G(a) was observed at the follow-up visit. However, there was no evidence for an IgE antibody response to either antigen. CONCLUSION: Both IgA and IgG antibodies to the immunodominant RSV-F(a) and G(a) antigens were readily detected in the nasal washes and sera from patients in this study. We were unable to demonstrate specific IgE antibody to these antigens and conclude that the production of IgE as a manifestation of a T(H)2 lymphocyte response to RSV is unlikely.     

AUTOANTIBODIES TO TAMM-HORSFALL PROTEIN IN PATIENTS WITH CYSTIC FIBROSIS

Abstract. Fasth, A. and Kollberg, H. (Department of Paediatrics and Department of Immunology, Institute of Medical Microbiology, University of Göteborg, and Department of Paediatrics, University Hospital, Umea Sweden). Autoantibodies to Tamm-Horsfall protein in patients with cystic fibrosis. Acta Paediatr Scand, 69: 189, 1980.—Sera from 35 patients, 17 boys and 18 girls, with cystic fibrosis were analysed for autoantibodies to the Tamm-Horsfall protein. Significantly ( p > 0.001) elevated levels of specific IgG and IgA, but not IgM antibodies to Tamm-Horsfall protein were found. There was a considerable overlap between the values in the disease group and the control group. The highest values were found among the patients with liver involvement. The patients with marked lung abnormalities as well as those with positive bacterial culture of sputum had normal antibody levels.     

19S IgM rheumatoid factor-7S IgG rheumatoid factor immune complexes isolated in sera of patients with juvenile rheumatoid arthritis

19S IgM rheumatoid factors (RF) and hidden 19S IgM RF have been associated with increased disease activity in juvenile rheumatoid arthritis (JRA). Recently, immune complexes (IC) were isolated from JRA sera by several methods which demonstrated the presence of 19S IgM RF. The present study evaluates 25 JRA patients' sera by separation on a Sepharose 4B column to which were bound F(ab')2 fragments of goat IgG antihuman IgM antibody to separate IgM-containing IC. The columns were sequentially eluted with 1 M ammonia and 0.1 M glycine-HCl buffer, pH 3.0. The isolated fractions were assayed for 19S IgM RF and 7S IgM RF by ELISA, IgG levels by immunodiffusion, and by preparative isoelectric focusing. The ammonia eluate from the alpha HIgM column revealed IgG, 19S IgM RF in six patients, and IgM RF in four patients. All were polyarticular-onset JRA patients. In the glycine-HCl eluate of sera, 19S IgM RF and IgG were also detected in 15 patients, all six seropositive, polyarticular-onset, six seronegative, polyarticular-onset, and three pauciarticular-onset patients. Significant 7S IgG RF titers were demonstrated in the glycine-HCl eluates of six patients, five seropositive, polyarticular-onset patients, and one seronegative, polyarticular-onset patient. Analysis by preparative isoelectric focusing of the IgM RF and IgG RF positive ammonia and glycine-HCl eluates showed IgM RF throughout the pH range (4-10), but the highest amount of IgM RF was in the pH range 4.0-5.5. Significant IgG RF titers were detected only in this restricted spectrotypic area of pH 4.0-5.5.(ABSTRACT TRUNCATED AT 250 WORDS)     

Serotype-specific serum IgG antibodies to lipopolysaccharides of Pseudomonas aeruginosa in cystic fibrosis: correlation to disease, subclass distribution, and experimental protective capacity

Various studies have demonstrated pronounced systemic IgG response to Pseudomonas aeruginosa (PA) infection in cystic fibrosis (CF). However, antibody response to serotype-specific lipopolysaccharides (LPS) has never been studied. ELISA for detection of IgG antibodies to LPS of nine PA-serotypes and to toxin A were performed with serum of 78 CF patients. Anti-LPS profiles of antibodies were confirmed by SDS-PAGE and immunoblotting techniques. The most frequent PA-serotypes found were immunotypes (IT) IT-1 and IT-2, and Habs-3 and Habs-4. Ten patients without PA colonization showed no detectable antibody titers. In patients with chronic PA colonization (n = 46), these antibody titers were significantly (p less than 0.005) higher than in patients with intermittent PA colonization (n = 22). Mean serum antibody titers to LPS of PA IT-1, IT-2, Habs-3, and Habs-4 correlated with duration of PA colonization and with disease severity. Subclass analysis of anti-LPS antibodies revealed elevated levels for all four IgG subclasses and for IgA1. The IgG antibodies to LPS of PA proved to be protective in a murine burn wound sepsis model. We conclude that anti-LPS antibodies to specific PA serotypes in serum may be a sensitive measure of severity and prognosis of CF. Patients with CF show adequate functional immune response to LPS of PA, and it is possible that vaccination against PA before colonization could induce protective immunity.     

Antinuclear antibodies in juvenile chronic arthritis.

One hundred patients with juvenile chronic arthritis (JCA) were studied with respect to granulocyte-specific and organ-nonspecific antinuclear antibodies (GS- and ON-ANA) in relation to clinical features of disease. Seventy-two were girls and 28 boys. Sixty-seven patients had IgG ANA, 31 IgM, 10 IgA, 6 IgD, 19 IgE and 35 had ANA, which fixed complement C3. Sixteen of 17 sera containing IgG GS-ANA were from girls. The prevalence of IgG GS-ANA increased with the number of joints affected. No patient with the acute febrile type of the disease had IgG GS-ANA or CS fixing ANA. The prevalence of IgG ON-ANA did not differ significantly in the mono-, pauci-, polyarticular and acute febrile types of JCA. Patients showing clinical activity more frequently had IgG and IgM ANA and C3 fixing ANA. The high titers of ANA were most often seen in girls. Chronic uveitis occurred in 10 of the patients and IgG ANA were present in sera from all of these.     

Altered antibody isotype in cystic fibrosis: possible role in opsonic deficiency

Patients with cystic fibrosis (CF) whose respiratory tracts are colonized with Pseudomonas aeruginosa (PA) may develop a specific opsonic deficiency for alveolar macrophage phagocytosis of PA. We examined the possible role of altered antibody (Ab) isotype in this phenomenon by measuring serum levels and distribution of IgG and IgG subclass Ab (IgG1, IgG2, IgG3, and IgG4) to the major opsonic immunodeterminant, serotype-specific lipopolysaccharide (LPS), by means of enzyme-linked immunosorbent assays employing monoclonal secondary antibodies, and comparing these results to the serum opsonic capacity in an in vitro murine alveolar macrophage phagocytic assay. Twenty-one patients with CF who were colonized with PA had approximately a 30-fold elevation of PA LPS IgG Ab levels and higher IgG subclass 1-4 Ab compared to 10 uncolonized patients with CF and 11 healthy controls (p less than 0.05-0.0005 depending on the isotype). Colonized patients with CF had a shift in PA LPS Ab distribution toward IgG3 compared to uncolonized patients with CF (p less than 0.02). A surprising finding was that uncolonized patients with CF had lower levels (p less than 0.05) and proportion (p less than 0.002) of PA LPS IgG2 Ab than controls, with an apparent shift to higher levels and proportion of PA LPS IgG4 (p less than 0.01). Serum from colonized patients with CF showed diminished opsonic capacity for phagocytosis of PA compared to uncolonized patients and controls (p less than 0.005), with 42% showing inhibitory activity. Functional Ab was also found to be inhibitory at high (greater than 500 ng/ml) concentrations. Serum opsonic capacity appeared to include a noncomplement cofactor for optimal activity.(ABSTRACT TRUNCATED AT 250 WORDS)     

Pediatric acquired immunodeficiency syndrome with negative human immunodeficiency virus antibody response by enzyme-linked immunosorbent assay and Western blot

A 5-month-old white girl having persistent oral candidiasis was brought to medical attention because of acute respiratory distress, pneumonia, and hypoxia that worsened despite supportive care and antibiotics. Bronchial lavage fluid yielded Pneumocystis carinii. The diagnosis of acquired immunodeficiency syndrome (AIDS) was suspected, although enzyme-linked immunosorbent assay (ELISA) and Western blot tests were both negative for human immunodeficiency virus (HIV) antibody. Immunologic evaluation included the following results: a low normal CD4/CD8 ratio 0.88, CD4 lymphocytes 493/microL, and elevated IgA 539 mg/dL and IgM 175 mg/dL with normal IgG 492 mg/dL. Lymphocyte stimulation study results were depressed. Lymphocytes sent for culture were subsequently positive for HIV. The mother was HIV antibody positive by enzyme-linked immunosorbent assay and Western blot but belonged to no high-risk group and was asymptomatic except for chronic diarrhea. The father was HIV antibody negative. The patient was treated with pentamidine and IV gamma-globulin with good clinical response and a rapid decrease of IgM and IgA toward normal values. Subsequent candidal pneumonia and candidal esophagitis were treated successfully with amphotericin B. The patient has received prophylactic IV gamma-globulin infusions for 6 months and remains HIV negative by enzyme-linked immunosorbent assay and Western blot. This case of pediatric AIDS highlights the need to consider HIV infection in the differential diagnosis of any child with physical findings or illnesses suggestive of AIDS-related complex or AIDS, even when HIV serologic findings are negative and parents belong to no high-risk group. Parental testing for HIV antibody is suggested in such cases.     

Autoantibodies directed against bactericidal/permeability-increasing protein in patients with cystic fibrosis: association with microbial respiratory tract colonization

BACKGROUND: Cystic fibrosis (CF) is associated with the appearance of serum autoantibodies directed against bactericidal/permeability-increasing protein (BPI). OBJECTIVES: To determine the age-specific seroprevalence rates of anti-BPI-IgG and IgA in a population of patients with CF and to correlate anti-BPI antibody concentrations with microbial respiratory tract colonization and pulmonary function variables at the time of serum sampling and 6 years thereafter. METHODS: Determination of BPI antibodies of the IgG and IgA isotypes using a commercial enzyme-linked immunosorbent assay in sera of a CF serum bank of 1992; correlation of anti-BPI antibody concentrations with age, clinical score, pulmonary function variables in 1992 and 1998, total serum immunoglobulin isotype concentrations and respiratory tract colonization with Pseudomonas aeruginosa and Aspergillus spp. RESULTS: Seventy-one patients (age in 1992, 14.1 +/- 7.5 years) were studied. Reactivities for anti-BPI-IgG and IgA were found in 28 (39%) and 26 (37%) patients, respectively. The seroprevalence of anti-BPI-IgA, but not IgG, increased significantly with age. P. aeruginosa colonization was associated with elevated concentrations of anti-BPI-IgG (P = 0.003) and IgA (P = 0.037). There were significant negative correlations between pulmonary function variables (vital capacity, forced expiratory volume in 1 s) in 1992 and 1998, respectively, and concentrations of anti-BPI-IgG or IgA in a multiple regression analysis. Anti-BPI-IgG, but not IgA, remained significantly associated with P. aeruginosa colonization (P = 0.006) and with reduced vital capacity (P = 0.01) in 1998 after correction for total serum isotype concentration. CONCLUSIONS: Anti-BPI-IgG are strongly associated with concurrent P. aeruginosa colonization and with long term restrictive pulmonary function abnormalities.     

ANTINUCLEAR ANTIBODIES IN JUVENILE CHRONIC ARTHRITIS

ABSTRACT. One hundred patients with juvenile chronic arthritis (JCA) were studied with respect to granulocyte-specific and organ-nonspecific antinuclear antibodies (GS- and ON-ANA) in relation to clinical features of disease. Seventy-two were girls and 28 boys. Sixty-seven patients had IgG ANA, 31 IgM, 10 IgA, 6 IgD, 19 IgE and 35 had ANA, which fixed complement C3. Sixteen of 17 sera containing IgG GS-ANA were from girls. The prevalence of IgG GS-ANA increased with the number of joints affected. No patient with the acute febrile type of the disease had IgG GS-ANA or C3 fixing ANA. The prevalence of IgG ON-ANA did not differ significantly in the mono-, pauci-, polyarticular and acute febrile types of JCA. Patients showing clinical activity more frequently had IgG and IgM ANA and C3 fixing ANA. The high titers of ANA were most often seen in girls. Chronic uveitis occurred in 10 of the patients and IgG ANA were present in sera from all of these.     

狼疮抗凝集物检测在系统性红斑狼疮、原发性血小板减少症中的临床应用

目的通过对系统性红斑性狼疮(SLE)310例和原发性血小板减少症(ITP)249例狼疮抗凝集物(LAC)和抗心磷脂抗体亚型(aCL-IgG、IgM、IgA)的测定,研究其与SLE临床表现的关系及LAC在ITP转归中的意义。方法采用脑磷脂-白陶土法(KCCT)及校正试验检测患儿血浆LAC;采用酶联免疫吸附试验(ELISA)测定息儿血清aCL-IgG,IgM、IgA。结果SLE 组中,66.1%显示体内存在高含量LAC,其中45.9%并狼疮肾炎;46.8?L抗体升高,其中90.2%为IgG和(或)IgM,分别有46.9%和11.7%是狼疮并中枢神经系统及血液系统病变。ITP组105例LAC阳性患儿中36.2%经抗核抗体(ANA)检测确诊为SLE,7.6%在2个月-2.4年后发展为SLE。结论LAC和aCL抗体亚型的水平与SLE临床表现密切相关,LAC在狼疮并肾脏病变中为优势病理性自身抗体;aCL抗体亚型的水平则与狼疮性血栓性血管炎性病变有相关关系。对单纯患有ITP的患儿应进行LAC动态观察,可及早确定疾病的转归。