肺炎支原体抗体IgM阳性患儿831例临床分析

目的分析肺炎支原体感染患儿的临床及实验室资料,为诊断和治疗肺炎支原体感染提供依据。方法采用ELISA法检测以发热、呼吸道疾病住院患儿肺炎支原体IgM,被动凝集法检测血清肺炎支原体混合抗体。透射比浊法检测C反应蛋白（CRP）,半定量检测降钙素原（PCT）,对其中831例肺炎支原体IgM阳性患儿分年龄段进行对比分析。结果肺炎支原体感染患儿男女构成间差异无统计学意义（P〉0．05）,而患儿的季节分布间差异有统计学意义（P〈0．01）。肺炎支原体感染惠儿中肺炎支原体肺炎占74．2％。肺炎支原体感染患儿血清CRP异常率48．2％与PCT的异常率18．3％比较,差异有统计学意义（P〈0．01）。结论肺炎支原体感染的患儿以学龄儿童为主;在诊治时,不能仅局限于呼吸系统;肺炎支原体感染辅助诊断中PCT的临床意义优于CRP。     

Serological diagnostics of hepatitis E virus infection

Development of accurate diagnostic assays for the detection of serological markers of hepatitis E virus (HEV) infection remains challenging. In the course of nearly 20 years after the discovery of HEV, significant progress has been made in characterizing the antigenic structure of HEV proteins, engineering highly immunoreactive diagnostic antigens, and devising efficient serological assays. However, many outstanding issues related to sensitivity and specificity of these assays in clinical and epidemiological settings remain to be resolved. Complexity of antigenic composition, viral genetic heterogeneity and varying epidemiological patterns of hepatitis E in different parts of the world present challenges to the refinement of HEV serological diagnostic assays. Development of antigens specially designed for the identification of serological markers specific to acute infection and of IgG anti-HEV specific to the convalescent phase of infection would greatly facilitate accurate identification of active, recent and past HEV infections.     

Clinicopathologic characteristics and steroid response of IgM nephropathy in children presenting with idiopathic nephrotic syndrome

There is no detailed information on clinical and immunopathologic features of immunoglobulin M nephropathy (IgMN) in children with idiopathic nephrotic syndrome (INS) in Pakistan. We reviewed our native renal biopsies over 15 years (July 1995-July 2010) and identified 135 cases of IgMN in nephrotic children (≤17 years). Their demographic, clinical and immunopathologic data were retrieved from biopsy reports and case notes. Mean age of this cohort was 7.6 ± 4.2 years. Males were 92 (68.1%) and females were 43 (31.9%). Steroid-dependent NS was seen in 88 (65.2%) cases and steroid-resistant NS in 47 (34.2%). Hematuria was found in 42 cases (31.2%) and hypertension in 27 (19.5%). The most common morphologic change was glomerular mesangial proliferation, found in 89 (65.9%) biopsies. Minor changes were seen in 46 (34.1%) cases and focal segmental glomerulosclerosis (FSGS) in 37 (27.4%). Immunofluorescence microscopy showed diffuse mesangial positivity of IgM in all cases. C3 and C1q were found in 72 (53.3%) and 40 (29.7%) cases, respectively. Our results show that IgMN is a fairly common cause of INS in children in Pakistan. It shows a spectrum of morphologic changes ranging from minor changes to FSGS.     

Minimal change disease with IgM+ immunofluorescence: a subtype of nephrotic syndrome

Immunoglobulin (Ig) M nephropathy is defined by electron-dense mesangial deposits and mesangial IgM visible by immunofluorescence (IF) without other histopathologic and immunofluorescent microscopic abnormalities. Certain patients have only immuno-positive (IgM+) IF. Children presenting with steroid-dependent or steroid-resistant nephrotic syndrome have a high prevalence of IgM+ IF with or without electron-dense deposits. We reviewed the clinical course of children with steroid-dependent or steroid-resistant nephrotic syndrome who underwent renal biopsy at Texas Children‘s Hospital from 1989 to 2006 to further characterize IgM+ IF in children with nephrotic syndrome. Of the 55 children with steroid-resistant or -dependent minimal change disease (MCD), 23 had IgM+ IF. Of these 23 children, 61% had microscopic hematuria at presentation, 48% (11/23) were steroid-dependent, and 48% (11/23) steroid-resistant (one underwent biopsy prior to steroid therapy). We compared the efficacy of adjuvant treatment with cyclophosphamide and cyclosporine: 18% initially treated with cyclophosphamide obtained remission, while 55% had no response; 83% obtained subsequent remission with cyclosporine. Of those initially treated with cyclosporine, 88% obtained complete or partial remission. IgM+ IF may be surrogate marker for the severity of MCD. Based on our results, children with MCD and IgM+ IF have a better response to cyclosporine than cyclophosphamide.     

HCMVpp65抗原、HCMV mRNA和IgM抗体检测在诊断HCMV活动性感染中的比较

目的比较人巨细胞病毒（HCMV）pp65抗原、HCMV mRNA和血清HCMV—IgM抗体检测3种方法在诊断HCMV活动性感染中的实用意义。方法采集医院TORCH检查HCMV—IgM阳性的病人外周血（60份）。将标本分2份2ml和3ml,别用于HCMV mRNA和pp65检测。将三者结果进行比较。结果pp65抗原检测的结果与IgM抗体检测的阳性符合率为81．67％。与HCMV mRNA检测相比pp65抗原检测法的符合率、特异度和敏感度分别为81．67％,81．81％和81．63％。而且高pp65抗原血症与患者的临床症状密切相关。结论pp65抗原血症反映该病毒活动状况,可监测HCMV活动性感染,联合HCMV—IgM的检测可以提高临床的诊断率并可用于指导临床用药及监测药物疗效。     

Multiple sclerosis patients with anti-lipid oligoclonal IgM show early favourable response to immunomodulatory treatment

Background and purpose:  Interferon beta and Glatiramer acetate are safe immunomodulatory treatments (IT) for multiple sclerosis (MS), but not always effective. New drugs are available, although they show more side-effects and unknown long-term safety profile. Anti-lipid oligoclonal IgM bands (OCMB) distinguish MS patients with early aggressive course. We prospectively studied if IT are effective in these patients or if they are candidates for more aggressive drugs as first therapeutic option.
Methods:  Seventy-five clinically isolated syndrome patients were studied. OCMB and conversion to MS were assessed. Patients suffering at least two demyelinating events within 3 years were considered eligible to start IT.
Results:  Eighteen patients showed OCMB (M+) and 57 lacked them (M−). All M+ patients and only 25 M− patients were treated. The other 32 M− patients suffered less MS attacks than those required to initiate treatment. IT similarly reduced relapse rate in both treated groups ( P  < 0.0001) and reduced Expanded Disability Status Scale (EDSS) progression in M+ patients, whose EDSS score had significantly increased before treatment. EDSS did not change in M− patients during follow-up, regardless if they were treated or not.
Conclusions:  Oligoclonal IgM bands identify MS patients who are candidates for early immunomodulatory treatment as IT improves their initial aggressive disease course.     

Anti-amyloid beta protein antibody passage across the blood-brain barrier in the SAMP8 mouse model of Alzheimer's disease: an age-related selective uptake with reversal of learning impairment

Amyloid beta protein (Abeta) levels are elevated in the brain of Alzheimer's disease patients. Anti-Abeta antibodies can reverse the histologic and cognitive impairments in mice which overexpress Abeta. Passive immunization appears safer than vaccination and treatment of patients will likely require human rather than xenogenic antibodies. Effective treatment will likely require antibody to cross the blood-brain barrier (BBB). Unfortunately, antibodies typically cross the BBB very poorly and accumulate less well in brain than even albumin, a substance nearly totally excluded from the brain. We compared the ability of two anti-Abeta human monoclonal IgM antibodies, L11.3 and HyL5, to cross the BBB of young CD-1 mice to that of young and aged SAMP8 mice. The SAMP8 mouse has a spontaneous mutation that induces an age-related, Abeta-dependent cognitive deficit. There was preferential uptake of intravenously administered L11.3 in comparison to HyL5, albumin, and a control human monoclonal IgM (RF), especially by hippocampus and olfactory bulb in aged SAMP8 mice. Injection of L11.3 into the brains of aged SAMP8 mice reversed both learning and memory impairments in aged SAMP8 mice, whereas IgG and IgM controls were ineffective. Pharmacokinetic analysis predicted that an intravenous dose 1000 times higher than the brain injection dose would reverse cognitive impairments. This predicted intravenous dose reversed the impairment in learning, but not memory, in aged SAMP8 mice. In conclusion, an IgM antibody was produced that crosses the BBB to reverse cognitive impairment in a murine model of Alzheimer's disease.     

冠心病与巨细胞病毒初期感染的相关性研究

目的探讨人类巨细胞病毒初期感染与冠心病发生发展的关系。方法用捕获ELISA法检测血清HCMV—IgM,酶法检测血脂4项,免疫比浊法检测C-反应蛋白（CRP）,并进行比较。结果冠心病组（61例）、健康对照组（44例）和其他疾病组（48例）的HCMV—IgM阳性率分别为8．20％、2．27％和4．17％,冠心病组与对照组之间无统计学差异（P〉0．05）;冠心病组血脂4项和CRP均高于健康对照组,有统计学差异（P〈0．05）。结论尚不能认为冠心病与巨细胞病毒初期感染有关。