Human granulocytic anaplasmosis in eastern France: clinical presentation and laboratory diagnosis

Human granulocytic anaplasmosis (HGA) is a tick-borne infection characterised by an acute, nonspecific febrile illness. To date, few clinical cases have been supported by both a positive polymerase chain reaction (PCR) assay and subsequent seroconversion against Anaplasma phagocytophilum antigen all over Europe. We report here 3 consecutive cases of HGA that occurred during the summer of 2009 which fulfilled the epidemiologic, clinical, and biological criteria for HGA. These data highlight PCR assay on ethylenediaminetetraacetic acid blood rather than serology as the diagnostic test of choice during the acute phase of the disease. In endemic areas, HGA should be investigated in patients presenting an undifferentiated febrile illness with cytopenia, elevated rates of liver enzymes, and increased C-reactive protein values.     

云南省德钦县犬感染嗜吞噬细胞无形体的调查

目的 了解云南省德钦县犬感染嗜吞噬细胞无形体的状况。方法 对2013-2014年期间在德钦县采集的315份犬血标本,应用巢式聚合酶链反应进行嗜吞噬细胞无形体16S rRNA基因扩增和测序分析,并将所测序列与GenBank中注册的基因序列进行同源性和进化树分析。结果 315份犬血样本中共有18份扩增到目的片段,总阳性率为5.71%(18/315),其中中华田园犬的阳性率为7.14%(12/168),藏犬的阳性率为5.13%(4/78),哈巴犬的阳性率为2.99%(2/67),狼犬中未检出HGA。所检出的嗜吞噬细胞无形体16S rRNA基因与GenBank中收录的部分嗜吞噬细胞无形体16S rRNA基因序列的同源性高达99%～100%。进化树分析结果显示,当地无形体分为2类流行株,将其命名为Yunnan HGA1和Yunnan HGA2,分别占检出菌株的16.67%和83.33%。Yunnan HGA1与在乌拉圭、西伯利亚和远东地区发现的全沟硬蜱中检测到的无形体片段(HM366583)同源性为100%,Yunnan HGA2与加拿大发现的肩突硬蜱中检测到的无形体片段(HG916766)同源性为99%。结论 云南省德钦地区犬存在嗜吞噬细胞无形体的感染,进一步开展相应媒介、宿主及人群感染调查十分必要。     

Epidemiological survey of tick-borne encephalitis virus and Anaplasma phagocytophilum co-infections in patients from regions of the Czech Republic endemic for tick-borne diseases

During the period 2000-2003, patients hospitalized for suspected tick-borne encephalitis in the Czech Republic were screened for possible A. phagocytophilum co-infection. Blood samples taken at admission were tested for the presence of A. phagocytophilum DNA by nested PCR using a modified target sequence as an internal control, and sera were tested for the presence of antibodies by indirect immunofluorescence and western blotting methods using cell-culture-derived antigens. To verify the assay specificity, a set of 45 sera of Patagonian residents served as a non-tick-exposed control group, and a set of 14 B. henselae-positive sera was used to check cross-reactivity. Of 809 patients hospitalized, 80 (9.9%) showed IgG antibodies reactive to A. phagocytophilum at > or =80 (reciprocal dilution factor) and 50 (6.2%) at > or =160; two (0.2%) patients showed elevated IgM titers of 40. No full blood obtained from 162 patients tested positive in PCR when false negativity was excluded. During hospitalization, the diagnosis of tick-borne encephalitis was confirmed in 536 patients, 57 (10.6%) of whom had anti-A. phagocytophilum IgG antibodies reactive at > or =80 and 41 (7.6%) at > or =160, which did not differ significantly from the whole set (P = 0.66/0.30), the maximum IgG titer registered was 5120, and no IgM titer reached the 40 cut-off. Available paired sera from 189 tick-borne encephalitis patients showed no significant shifts, but one case of slight seroconversion (IgG shift from < 80 to 320) was detected in one of the non-tick-borne encephalitis patients. The sex of the patient showed no significance for the prevalence of A. phagocytophilum antibodies; however, the seropositive patients were older on average than those who were seronegative (43.5 +/- 15.9 vs. 37.9 +/- 18.3 years, P = 0.05). Clinical manifestation of the disease did not differ noticeably between patients with and without A. phagocytophilumreactive antibodies, except for fever duration, which was significantly longer in patients with titers > or =1280. Overall, A. phagocytophilum co-infection did not seem to be a frequent and/or significant complication of tick-borne encephalitis acquired in the Czech Republic.     

Serologic evidence of Anaplasma phagocytophilum infections in patients with a history of tick bite in central Slovakia

The aim of this study was to determine the risks of human anaplasmosis in an area of central Slovakia endemic for Lyme borreliosis. The circulation of Anaplasma phagocytophilum in ticks and wild animals has been observed in natural foci in this area for several years. Samples of human sera from patients with Lyme borreliosis and persons with a history of recent tick bite and clinical symptoms indicating Lyme borreliosis were collected in central Slovakia. A total of 76 human sera were analyzed using an indirect HGE IgG immunofluorescent assay kit. IgG antibodies against A. phagocytophilum were found in 19 (25%) sera (15 female, 4 male patients). A. phagocytophilum infection was serologically confirmed in one (3.8%) child, 12 (38.7%) persons aged 22-56 and six (31.6%) persons older than 56. A statistically significant difference in seroprevalence (P < 0.01) was observed between children (3.8%, 1/26) and adults (36%, 18/50). Antibodies against A. phagocytophilum were detected in seven patients with clinically diagnosed Lyme borreliosis and in another seven individuals with assessed antiborrelia antibodies. IgG antibodies against A. phagocytophilum were detected in five persons seronegative for borrelia. The most frequent clinical symptoms in patients with positive A. phagocytophilum serology were cephalalgia, arthralgia, myalgia, fever, exanthema, neurological symptoms and lymphadenopathy. Positive sera were obtained from patients living in villages and towns in the orographic entities Vtácnik (5/19), Stiavnické vrchy (1/19), Kremnické vrchy (10/19) and Ziarska kotlina (3/19). Our results demonstrate the risk of acquiring A. phagocytophilum infection in natural foci in central Slovakia. Human anaplasmosis should be considered in the differential diagnosis, especially in cases of acute febrile illness with tick-bite history.     

A comparative study of the etiology of adult upper and lower respiratory tract infections in the community

Lower respiratory tract infection and upper respiratory tract infection (URTI) are very common, but the etiology is not diagnosed in routine practice. The objective of this study was to determine and compare the frequency distribution of the various infectious etiologies for these diseases. One hundred seventy five adults in the community with febrile LRTI and 75 with febrile URTI were included in a purely serologically based prospective study. Paired sera were obtained for each of the patients and were tested by EIA or immunofluorescence methods to identify 14 different pathogens. Only a significant change in antibody titers between the paired sera was considered diagnostic. At least one infectious etiology was identified in 167 patients (67%). In the LRTI group, infection with at least one of 7 respiratory viruses was found in 88 patients (50%). One of the atypical pathogens was found in 40 patients (23%), of these Legionella spp. in 19 (11%) and Mycoplasma pneumoniae in 18 (10%). A bacterial etiology was found in 19 patients (11%), of these Streptococcus pneumoniae in 8 (5%) and beta-hemolytic streptococci group A in 5 (3%). The frequency distribution of etiologies in the URTI group was not significantly different from the LRTI group, except for M. pneumoniae that was identified in only one patient with URTI (p = 0.015). More than one etiologic agent was found in 42 (17%) of the patients. LRTI is caused by a broad spectrum of etiologies, with respiratory viruses predominating and a moderate, but significant, prevalence of atypical pathogens. The frequency distribution of etiologies for URTI is similar to LRTI. In a significant proportion of patients with URTI and LRTI there is serologic evidence of infection with more than one pathogen. The justification and benefit of distinguishing between URTI and LRTI in routine clinical work is doubtful. When a decision is reached to treat RTI patients with an antibiotic, it is logical to use a macrolide or tetracycline.     

Evaluation of six serological tests in diagnosis and postoperative control of pulmonary hydatid disease patients

Latex agglutination (LA), passive hemagglutination (PHA), immunoelectrophoresis (IEP) and specific IgE, IgM, IgG enzyme-linked immunosorbent assay (ELISA) tests for diagnosis and postoperative follow-up of 79 patients with surgically confirmed pulmonary hydatidosis were evaluated. Specific IgG ELISA was the most sensitive test (83.5%) and the least sensitive tests were specific IgE ELISA (44.3%) and IEP (50.6%). The specificity obtained for all the serologic test was above 97% in all cases. The greatest number of false positives in all tests (except IEP) occurred in patients with Taenia saginata and Taenia solium cysticerci infestations and in patients with lymphoma and leukemia. Specific IgG ELISA demonstrated the highest negative predictive value (93.8%). No statistically significant differences (p > 0.050) were found in the sensitivity of the tests when patients with only one cyst and patients with various cysts were compared. Considering only the patients without relapse, the percentage of seropositive patients increased in all tests at 1 and 3 months after surgery. After that time the percentage of seropositive patients decreased. At 48 months after surgery all patients without relapse became negative in IEP, specific IgE ELISA, and specific IgM ELISA. The antibody titers in all seropositive patients increased during the 3 months after surgery. From these 3 months onward, antibody levels decreased in all serologic tests studied in the group of patients without relapse. The patients who had relapses during the first year after surgery presented persistently elevated antibody titers in all postoperative sera. The antibody titers of the patients who relapsed between the third and fourth years after surgery decreased progressively the third month after surgery, and increased in the serum obtained at the moment of relapse diagnosis. Our results show that persistence of elevated antibody titers in patients with pulmonary hydatidosis in the year after surgery or titer increase after a progressive decrease are indicative of relapse or reinfection.     

Transient autoantibodies with elevated complement levels in common viral diseases

Autoantibodies including rheumatoid factor (RF), anti-DNA antibody (ADA), and anti-nuclear factor (ANF) in addition to cold agglutinin and heterophil antibody titers were tested for in a total of 219 patients with common viral diseases. The diseases included varicella, influenza, measles, mumps, herpes zoster, hand-foot-mouth syndrome, and exanthem subitum . A high incidence of RF (23%) was demonstrated in varicella patients, and ADA and ANF (16% and 12%, respectively) were most frequently detected in the influenza cases. Those autoantibodies were most frequently found in patients with influenza. Each serum complement component and total hemolytic complement (CH50) were also assayed. Elevated levels of the fourth (C4) and ninth (C9) components of complement, along with elevated CH50, were observed in most patients. Follow-up studies indicated that those autoantibodies as well as other antibodies disappeared 3 to 8 weeks after the onset of infection. The present study indicates that substantial but transient alterations in the immune system accompanied by autoimmune phenomena and elevated levels in the complement components can occur in viral infections.     

Examining the association between vaccine reactogenicity and antibody titer dynamics after the third dose of BNT162b2 vaccine using a mixed-effects model

BackgroundTo mitigate the COVID-19 pandemic, many countries have recommended the use of booster vaccinations. The relationship between the degree of adverse vaccine reactions and elevated antibody titers is of interest; however, no studies have investigated the temporal changes in antibody titers based on repeated measurements after a third dose of the BNT162b2 vaccine.MethodsThis prospective longitudinal cohort study was conducted with 62 healthcare workers who received a third dose of the BNT162b2 at Okayama University Hospital, Japan. Venous blood draw and fingertip whole blood test sample collection were conducted at the early (3–13 days) and 1-month time points; only FWT sample collection was conducted at the 2-month time point. Information on adverse reactions within 1 week after vaccination was also obtained. The association between fever of 37.5 °C or higher and antibody titers after the third dose of BNT162b2 was examined using a mixed-effects model and Poisson regression with robust variance.ResultsA trend toward higher antibody titers in the early period after vaccination was observed in the febrile individuals, but the differences were not significant at 1 and 2 months post-vaccination (the partial regression coefficient for fever was 8094.3 [-1910.2, 18,098.8] at 1 month after vaccination, and 1764.1 [-4133.9, 7662.1] at 2 months after vaccination in the adjusted models).ConclusionThe findings suggest that the presence of fever after the third vaccine does not predict a sustained elevation in serum antibody titers.     

放射性~(125)I粒子治疗老年胰腺癌的临床研究

目的探讨放射性125I粒子治疗75岁以上胰腺癌患者的有效性及可行性。方法通过超声内镜或经皮超声引导对12例75岁以上胰腺癌患者行125I粒子种植治疗,其中11例黄疸患者同时进行胰胆管支架植入。患者均未行放化疗,术后进行随访。结果所有患者均成功植入125I粒子,未发生严重并发症。治疗1周后,9例有腹痛的患者中6例(66.7%)疼痛部分缓解,3例(33.3%)轻度缓解,全部有效。术后1月,肿瘤部分缓解2例(16.7%),稳定9例(75.0%),进展1例(8.4%)。预期中位生存期为9.5个月,预期1年生存率为29.2%。结论 125I粒子种植治疗75岁以上胰腺癌患者安全有效,与其他姑息治疗相结合是很好的选择。     

Factors associated with anti-SARS-CoV-2 IgG antibody production in patients convalescing from COVID-19

IntroductionAmong patients with coronavirus disease 2019 (COVID-19), the factors that affect anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody production remain unclear. This study aimed to identify such factors among patients convalescing from COVID-19.MethodsThis study comprised patients who had been diagnosed with COVID-19 between January 1 and June 30, 2020 and gave consent for anti-SARS-CoV-2 spike protein antibody measurement using enzyme-linked immunosorbent assay during their acute and/or convalescent phases. Factors related to elevated antibody titers and the relationship between the days from disease onset and the development of antibody titers were assessed.ResultsA total of 84 participants enrolled in the study. Nineteen participants had antibody titers measured during the convalescent phase only, and 65 participants had antibody titers measured during the acute and convalescent phases. The antibody titers peaked in weeks 5 and 6. The stepwise multivariate log-normal analysis revealed that male sex (P = 0.04), diabetes mellitus (P = 0.03), and high C-reactive protein levels during the disease course (P < 0.001) were associated with elevated IgG antibodies. Glucocorticoid use was not associated with antibody titers.ConclusionThe study found that high values of maximum CRP levels during the acute phase, male sex, and diabetes mellitus were associated with elevated antibody titers. Antibody titers tended to be highest in the first 5 or 6 weeks after the onset of symptoms.     

Serial carcinoembryonic antigen (CEA) blood levels in patients with ulcerative colitis

Fifty-seven patients with ulcerative colitis were folloued 1-49 months (mean, 18 months) with serial CEA determinations during periods of remission, mild relapses, and severe relapses. Elevated CEA titers correlated with activity and possibly extent of disease: 12% of patients with proctitis, 47% of patients with left-sided colitis, and 60% of patients with transverse or universal colitis had elevated CEA titers during a flare. Moreover, 24% of patients with mild flares and 86% of patients with severe flares had elevated CEA titers. Ninety-two percent of patients with extensive disease and severe flares had elevated CEA titers. Elevated CEA titers were correlated with histologic findings in three patients. Inflammation of mucosa was demonstrated by colonoscopy and confirmed by biopsy in one patient with persistently elevated CEA titers during clinical remission. In two other patients with active disease whose CEA titers fell prior to colectomy, marked denudation of colonic mucosa was noted. In this study, a transiently elevated CEA titer indicated either clinically active ulcerative colitis or active inflammation of colonic mucosa.     

Anti-skeletal muscle and anti-acetylcholine receptor antibodies in patients with thymoma without myasthenia gravis: relation to the onset of myasthenia gravis.

We measured the anti-skeletal muscle (SM) antibody titers in sera from 46 patients with thymoma but without Myasthenia gravis (MG) in order to determine whether the presence of anti-SM antibody is linked to the combination of thymoma-MG, or to thymoma alone. We detected anti-SM antibodies in 18 of these sera, of which 15 had concomitantly elevated titers of anti-AChR antibodies. Moreover, 9 of whom had experienced the onset of MG after surgery. In contrast, no patient without elevations in both antibodies developed MG during the followup. We conclude that the presence of anti-SM antibodies is linked strongly with thymoma associated with MG, but not with thymoma alone.     

Elevated Levels of Antibodies to Epstein-Barr Virus Antigens in Sera and Synovial Fluids of Patients with Rheumatoid Arthritis

The frequencies and levels of antibodies to Epstein-Barr virus (EBV)-specific antigens were determined in paired sera and synovial fluids from patients with rheumatoid arthritis (RA) and in sera from patients with other connective tissue diseases; i.e., systemic lupus erythematosus, progressive systemic sclerosis, and osteoarthritis (OA). The specimens were also tested for the presence of antibodies to RA-associated nuclear antigen. Compared to healthy controls, the patients' sera showed increased frequencies of elevated antibody titers (≥320) to Epstein-Barr viral capsid antigen, a correspondingly enhanced (twofold to threefold) geometric mean titer, and an increased frequency of antibodies at elevated titers (≥10), usually to the restricted component and rarely the diffuse component of the early antigen complex. Levels of antibody to the EBV-associated nuclear antigen were within the normal range. Enhancement of antibody titers was more pronounced in seropositive RA patients (i.e., positive for rheumatoid factor) than in those who were not. Enhancement was also found in systemic lupus erythematosus and progressive systemic sclerosis. Antibody to RA-associated nuclear antigen was detected at an increased frequency only in the group of seropositive RA patients (90%), as compared to 8-15% in the other connective tissue diseases and 6-8% in healthy controls. The antibody titers in the synovial fluids equaled or were at most twofold higher or lower than those in the sera. In addition, levels of EBV-specific antibodies were studied serially over a period of 6-10 mo in patients with RA and OA. Parameters of disease activity were determined and compared to antibody levels. EBV-specific antibodies in sera of OA patients remained constant and within normal limits throughout the study. Although EBV-specific antibodies were often elevated in RA patients, they also remained constant, with the exception of three patients, who showed gradual increases in one of the four antibodies, which did not correlate with disease activity.     

First documented case of human granulocytic ehrlichiosis in Austria

We report the first documented case of human granulocytic ehrlichiosis (HGE) in Austria. The infection was acquired near Arzl in the surroundings of Innsbruck in northern Tyrol. Except for a biphasic course of illness, presentation in this 33-year-old female patient was comparable to clinical findings observed in other European adults with high fever, transient thrombocytopenia, elevated levels of CRP and LDH, arthralgias, myalgias, fatigue and subfebrile temperature. Flu-like symptoms started about seven days after a tick bite and lasted for ten days, followed by an asymptomatic interval of three days and an acute onset of fever up to 39.5 degrees C on day 20. On admission, the patient showed high antibody titres against Anaplasma phagocytophilum (IgG 1:1024, IgM 1:640); six weeks later the IgG-titre had risen to 1:2048, and IgM-levels had fallen below 1:40. The demonstration of anti-platelet antibodies in acute-phase serum was noteworthy. We conclude that also in Austria HGE should be considered in patients with febrile thrombocytopenia, especially when the medical history reveals recent tick exposure.     

超声造影在不同类型子宫肌瘤诊断中的应用

目的 比较超声造影(CEUS)与常规超声在不同类型子宫肌瘤定性及定位诊断中的价值.方法 采用实时CEUS技术对56例不同类型子宫肌瘤进行观察,以病理为金标准,回顾性分析CEUS定性及定位诊断不同类型子宫肌瘤的准确性,并与常规超声比较.结果 CEUS与常规超声诊断肌瘤的总体符合率、肌壁间肌瘤符合率、黏膜下肌瘤和浆膜下肌瘤符合率分别为94.6%(53/56),73.2%(41/56);99.3%(31/32),78.1%(25/32);91.6%(22/24),66.7%(16/24).CEUS和常规超声显示总的肌瘤的数目及肌瘤边界清晰情况分别为92.8%(104/112),80.3%(90/112),91.9%(103/112),78.6%(88/112).CEUS和常规超声对典型子宫肌瘤的诊断符合率分别为95.8%(23/24),87.5%(21/24);对不典型子宫肌瘤的诊断符合率分别为93.8%(30/32),62.5%(20/32).两组结果相比较,差异均有统计学意义(P<0.05).结论 CEUS可以更好地显示子宫肌瘤的数目及边界,对不同类型及不典型子宫肌瘤的诊断符合率明显高于常规超声,可为子宫肌瘤的定性及定位诊断提供一种新方法.     

Spontaneous hypothyroidism in the follow up of Graves hyperthyroid patients treated with antithyroid drugs

AIM: Spontaneous hypothyroidism may follow the natural course of Graves disease (GD) after treatment with antithyroid drugs (ATD). Methods: We studied retrospectively 139 remitted Graves hyperthyroid patients treated with ATD, with a follow-up period of 17.5 years (range 6 to 25 years). Elevated serum concentration of thyroid-stimulating hormone and low serum thyroxine concentrations confirmed the diagnosis. RESULTS: Thirteen patients (median age, 41 years; 26 to 48 years) developed spontaneous hypothyroidism, 4 to 144 months (median, 48 months ) following withdrawal of ATD. The prevalence of hypothyroidism was 9.3% and the incidence was 2.3% per year (13/ 563.6 patients/year of observation). There was no association with types of drugs used or the regimens. Spontaneous hypothyroid patients showed elevated titers (P = 0.02) of serum antithyroid peroxidase antibody (TPOAb) at the end of treatment with ATD, compared with the titers found at the beginning. These patients also had higher titers of TPOAb (P = 0.01) in relation to euthyroid patients. In contrast, the changes in serum antithyroglobulin antibody titers were not significant. CONCLUSIONS: Because of the shift from euthyroidism to spontaneous hypothyroidism, GD patients demanded a strict follow up after ATD therapy. It seems that there is an effect of TPOAb on thyroid destruction.     

Rare case of severe rhabdomyolysis secondary to human granulocytic anaplasmosis

Anaplasma phagocytophilum (AP) is the causative agent of human granulocytic anaplasmosis (HGA), a tick-borne illness with highest incidence in north-eastern regions of the United States. This condition presents with vague constitutional symptoms and has been associated with laboratory derangements such as leukopenia, thrombocytopenia and transaminitis1. Rhabdomyolysis, however, is not one of these associations. We report a case of confirmed HGA associated with severe rhabdomyolysis, where no other cause was identified. The etiology of rhabdomyolysis secondary to AP infection is still unknown. A presumptive diagnosis of HGA can be made in the presence of fever, non-specific symptoms such as myalgias, laboratory derangements such as leukopenia and thrombocytopenia in an individual residing in an endemic area3. Serological confirmation should not delay treatment, given the rapid progression of this dangerous infection. Rhabdomyolysis should also be considered as part of supporting data in the diagnostic consideration for HGA.     

维持性血液透析患者乙肝表面抗体水平变化的观察分析

目的动态观察维持性血液透析(HD)患者血清乙型肝炎病毒表面抗体(抗-HBs)滴度水平变化。方法选择34例维持性血液透析患者,进行血清抗-HBs滴度检测,间隔6月后复查,分析前后抗体滴度水平的差异。结果34例患者中有28例观察前后的抗-HBs滴度降低,占82.4%;有6例抗-HBs滴度升高,占17.6%。抗-HBs滴度总体水平呈下降趋势,前后有显著差异(P<0.01)。结论维持性血液透析患者血清抗-HBs滴度水平随时间而不断变化,而且降低者所占比例明显高于升高者。     

Diagnostic value of tests for Toxoplasma gondii-specific antibodies in patients undergoing bone marrow transplantation

The value of Toxoplasma gondii-specific antibodies for the diagnosis of reactivated toxoplasmosis in immunocompromised patients is controversely discussed. The present study was performed to investigate the value of testing for antibodies against Toxoplasma gondii in patients undergoing bone marrow transplantation (BMT). Of 75 patients enrolled in the study, 53 (70.7%) were seropositive before BMT. Of these, 7 (13.2%) developed parasitemia after BMT as detected by polymerase chain reaction (PCR); three of these developed clinical symptoms compatible with reactivated toxoplasmosis that resulted in fatal toxoplasmosis in two cases. We did not detect specific antibody patterns or changes in specific antibody titers that could have predicted the development of parasitemia. Notably, 18 (81.8%) of 22 patients without specific IgG before BMT showed anti-T. gondii IgG after BMT, but none of them developed parasitemia. The results of the present study indicate that blood from both the donor and the recipient should be tested before BMT. Seronegative patients should be tested regularly after BMT to detect primary infections. Routine serological monitoring of patients seropositive before BMT does not contribute to the diagnosis of reactivated disease following BMT. In contrast, blood of seropositive patients should be screened by polymerase chain reaction (PCR) for Toxoplasma-specific DNA for the diagnosis of reactivation of infection with T. gondii.     

Anti-GM1, anti-central myelin proteins,and anti-cardiolipin autoantibodies during plasma-exchange in Guillain-Barré syndrome (GBS)

We measured the autoantibodies to GM1, central myelin proteins, and cardiolipin in 30 GBS patients using sensitive ELISA and Western blot techniques. The sequential modifications of titers during plasma-exchange (PE) and at follow-up were investigated in 15 patients. In pretreatment sera, we found significantly increased antibody titers to GM1 (37% of the patients), central myelin proteins (28%), and cardiolipin (21%). Seventeen patients out of 29 (58%) presented increased IgG or IgM antibody to at least one of the antigens considered as compared to 10 out of 70 controls (14%, P = 0.00001). By Western blot, IgG or IgM antibodies reactive with the triton insoluble fraction of central myelin were observed in 19 out of 28 GBS patients (67%). The follow-up measurements during and after PE showed a declining autoantibody titer in 10 out of 15 patients. However, in the remaining 5 GBS patients, we observed a persistently elevated titer or an increase from baseline values occurring during or after PE and reaching a peak. In 2 of the 5 patients, the titer peak preceded a clinical re-exacerbation. The presence of a persistently elevated or an increasing autoantibody titer during treatment with PE merits further investigation and may help to clarify the pathogenesis of GBS and improve its treatment. J. Clin. Apheresis 13:155–162, 1998. © 1998 Wiley-Liss, Inc.