Identification and analysis of two Mycobacterium abscess with different morphology / 中华检验医学杂志

Two types of Mycobacterium abscesses (Mab) were found in sputum from a patient with severe pneumonia in May 2020. One was Mycobacteriumabscessus with smooth morphology (Mab S), the other was Mycobacteriumabscessus with rough morphology (Mab R). Both of them were compared and drug susceptibility testing were performed to provide clinical scientific diagnosis and treatment. Morphology, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA were used to analyze Mab S and Mab R, phylogenetic evolution tree was constructed by gene sequence alignment for homology, proportion and broth drug test were used for in vitro drug sensitivity test. There were morphological differences between Mab S and Mab R. MALDI-TOF MS analysis showed that there were 223 protein peaks in Mab R and 147 protein peaks in Mab S. Mab S contained 1 397 bp and Mab R contained 1 402 bp as 16s rRNA gene sequencing revealed. Drug susceptibility testing showed that both of them were almost resistant to all antituberculosis drugs, but sensitive to most of antibiotics. Mab S and Mab R were not only different in manifestations, but also in protein and gene comparison. Both of them were generally resistant to antituberculosis drugs. Antibiotic combined therapy has been confirmed to be an effective treatment in clinic.

Amyloidosis secondary to ankylosing spondylitis:case report and literature review / 中华全科医师杂志

Three patients diagnosed as amyloidosis secondary to ankylosing spondylitis (AS) in Peking Union Medical College Hospital are reported.All 3 cases had renal abnormalities,2 cases were complicated with cardiac abnormalities,1 case was complicated with gastrointestinal abnormalities and 1 case was complicated with skin moss-like changes.Eleven cases of AS with amyloidosis were retrieved from Wanfang database and Pubmed database from 1997 to 2017.In total 14 cases,the male and female ratio was 5:2,the mean age of AS onset was (29.6± 10.5)years,and the mean age of amyloidosis diagnosed was(44.0± 10.5)years.Eight patients presented with edema and severe proteinuria,2 cases showed diarrhea,2 cases showed dyspnea,while 2 cases had no obvious symptoms.Thirteen cases had renal abnormalities and 1 case had only heart involvement.Of the 13 patients with renal involvement,2 cases were complicated with cardiac abnormalities,2 cases complicated with gastrointestinal abnormalities,2 cases complicated with skin abnormalities.The mean ESR was(83.7±22.6)mm/1 h,C reactive protein was(89±59)mg/L at onset.After the diagnosis of amyloidosis,9 patients were treated with TNF-α inhibitors,3 cases received symptomatic therapy,1 case underwent renal transplantation and 1 case were treated with peritoneal dialysis.In 9 patients treated with TNF-α inhibitors,8 cases were relieved and 1 case lost follow-up.Three patients who received symptomatic treatment all died,while patients receiving kidney transplantation and peritoneal dialysis were in stable condition.The study indicates that secondary amyloidosis often occurs in young male AS patients who have long course and poorly controlled disease,the kidney is the most common affected organ.TNF-α inhibitors may be effective for treatment of amyloidosis secondary to AS.

Prozone effect on indirect immunofluorescence assay for anti-nuclear antibody testing / 国际检验医学杂志

Objective To explore the influence of prozone effect on anti-nuclear antibodies (ANA) testing by indirect immunofluorescence assay (IIFA).Methods The samples with high titer of ANA (≥1∶1 000) were selected from 880fresh serum samples, and were subsequently diluted in 1∶100, 1∶1 000and 1∶10 000ratio.Prozone effect was defined as fluorescence intensity from 1∶1 000dilution was stronger than that from1∶100dilution.The samples with prozone effect were determined manually or by Sprinter XL and EUROPattern.The samples with prozone effect were further characterized by combinations of fluorescence patterns, fluorescence intensities and autoantibody specificities.Results A total of 880samples were tested.Importantly, 34samples displayed prozone effect (3.86％in total and 29.57％in samples with ANA≥1∶1 000).Interestingly, prozone effect was identified by manual detection as well as by Sprinter XL with similar fluorescence patterns and fluorescence intensities.Notably, EUROPattern can only select the central area for identification.Among all samples with prozone effect, 74.42％samples exhibited fluorescence intensities of≥1∶10 000.Speckled pattern was the most prevalent fluorescence patterns in samples with prozone effect (46.51％).In addition, anti-RNP antibodies (62.79％) were the most popular autoantibodies in samples with prozone effect, followed by anti-dsDNA antibodies (51.16％) and anti-SSA antibodies (51.16％).Conclusion Prozone effect was present in ANA testing, especially in samples with high titers, resulting in underestimating the titers.The study highlighted that special attention should be paid to the prozone effect in clinical practice.

Anti-mutant citrullinated vimentin antibody in the diagnosis of rheumatoid arthritis / 中华检验医学杂志

Objective This study aimed to assess the diagnostic value of anti-mutated citrullinated vimentin (MCV) antibodies in rheumatoid arthritis (RA) and its correlation with disease progression, extra-articular manifestations and overlap syndrome. Methods Retrospective Studies. Clinical data of 837 patients in PekingUnionMedicalCollegeHospitalfrom June to August 2017 were collected, including the result of anti-MCV, anti-cyclic citrullinated peptide (anti-CCP) antibodies, rheumatoid factor (RF), erythrocyte sedimentation rate (ESR) and High-sensitivity-C-reactive protein (CRP). According to the 1987 American College of Rheumatology classification criteria for rheumatoid arthritis, there were 323 patients diagnosed with RA, including 59 males and 264 females with the average age of 51 years. According to whether the RA patients have overlap syndrome with other autoimmune disease (AID) or have extra-articular manifestations, 258 cases were categorized into RA group, including 47 males and 211 females with the average age of 50 years; 14 cases were categorized into the group of overlap syndrome, including 1 male and 13 females with the average age of 36 years;51 cases were categorized into the group of extra-articular manifestations, including 11 males and 40 females with the average age of 59 years.According to 2010 rheumatoid arthritis classification criteria for destruction in joints, the radiographic changes were divided into 4 stages. There were 203 casesenrolled in our study, 88 caseswere fitted into early stage group (stage I)including 21 males and 67 females with the average age of 48 years; 115 caseswere fitted into progressive stage group, which compromisedstageⅡ (interim stage), stage Ⅲ (severe stage) and stage Ⅳ(final stage) cases, including 19 males and 96 females with the average age of 53 years. Mann-Whitney U test, x2 test, Receiver operating characteristic (ROC) curves and Spearmancorrelation coefficientwere used in Statistical analysis. Results Ⅰ Amongdiagnosed RA patients, 199 (61.6％) cases were positive for anti-MCV, anti-CCP and RFsimultaneously, 42 (13％) cases were positive for anti-MCV, which was higher than anti-CCP positive (1 cases, 0.3％) or RF positive (7cases, 2.2％). The difference was statistically significant(P<0.001, P<0.001). ⅡROC was calculated and MCV=35.95 U/ml was used as best-fit cut-off value. The AUC for anti-MCV was 0.867, while the sensitivity was 80.5％and specificity was 80.9％.ⅢThe detection levels of anti-MCV (682.8 (106.4-1000.0)), anti-CCP (407 (4.0-1536.0)) and RF (82.8 (21.1-244.9)) in the group of progressive stage were higher than those in the group of early stage (114.5 (28.5-1000.0), 62.5 (5.0-1020.7), 50.1 (6.7-127.1)), which showed a significant difference(P<0.05, P<0.05, P<0.05). The anti-MCV, anti-CCP and RF were positively related to the degree of joint destruction (r=0.229, P<0.05;r=0.187, P<0.05;r=0.167, P<0.05);anti-MCV and anti-CCP were positively related to extra-articular manifestation (r=0.152, P<0.05;r=0.136, P<0.05). Conclusion Anti-MCV antibodies are more sensitive in patients with RA, and have complementary diagnostic value for anti-CCP and RF-negative patients; high levels of anti-MCV and anti-CCP in RA patients are associated with RA progression and extra-articular involvement.

A multi-center clinical study for ANA specific autoantibodies detection by chemiluminescent immunoassay / 中华检验医学杂志

Objective To evaluate the clinical performance of chemiluminescent immunoassay (CLIA) on anti-nuclear antibody(ANA) specific autoantibodies testing.Methods A multi-center clinical study A total of 811 Sera samples were collected from 6 collaborating hospitals during the period of April to July 2016, and tested with CLIA and line immunoassay (LIA) in parallel for autoantibodies to ribonucleoprotein(RNP), smith antigen(Sm), SSA/Ro60,SSB/La, centromere protein B(CENPB), double-stranded DNA(dsDNA), nucleosome(Nuc), and ribosome P protein(Rib-P).The positive rate,specificity and qualitative coincidence rate for each antibody between CLIA and LIA methods were analyzed.All discrepant samples for systemic lupus erythematosus (SLE) highly specific autoantibodies (including anti-Sm, dsDNA, Nuc and Rib-P) were retested by enzyme linked immunosorbent assay (ELISA) and further analyzed with SLE disease cohort using McNemar test.Results The positive rate and specificity of CLIA and LIA for antibodies to ANA specific antigens were comparable.Excellent qualitative coincidence were found between CLIA and LIA for the detection of anti-RNP, SSA/Ro60, SSB/La and CENPB (Kappa>0.75), while the coincidence rate foranti-Sm, dsDNA, Nuc and Rib-P detection were moderate (0.4

Clinical significance of screening autoantibodies in individuals of physical examination / 中华检验医学杂志

Objectives To explore the clinical significance of autoantibodiesin individuals who accept a routine physical examination.Methods From April to June 2012, the serum of 932 individualsincluding 649 males and 283 females, from department of routine physical examination center of Peking Union Medical College Hospitalwerecollected , it uesd IIF for ANA, line immunoassay ( LIA) for specific ANAs antibodies and ELISA for the other antibodies , includinganti-CCP antibodies , AMA-M2, ACL antibodies and anti-anti-β2GPⅠantibodies.Chi-square test was used for data measurement of positive rate of autoantibodies in men and women;Fisher′s exact test was used when the data not meet the conditions of Chi-square test.Individualswith high-risk of autoimmune disease according to the results ofautoantibodies ( Titersof autoantibodies≥2-fold cut-off and accompanied with other autoimmune diseases related laboratory abnormalities) were recalled to visit doctor.Results Of the 932 cases, the overall positive rate of ANA was 11.27%.The positive rate of ANA was19.79%inwomen, which was significantly higher than thatin men (7.09%)(χ2 =32.6, P<0.01); the overall positive rate of ANAswas 8.69%, and the positive rate of ANA was13.43%inwomen, whichwas significantly higher than that in men ( 6.63%) (χ2 =11.49, P <0.01);the overall positive rates of AMA-M2, anti-CCP antibodies , anti ACL antibodies and anti β2GPⅠantibodies were 3.22%, 0.54%, 2.90%and 0.21% respectively , which were 2.83%, 0.71%, 3.18%and 0.71 % in women , and 3.39%, 0.46%, 2.77% and 0.00% in men respectively , there was no statistically significant of positive rate between female and male 58 patients accounting for 6.22% in high-risk of autoimmune disease were recalled , of which 15 cases, accounting for 1.61% were diagnosed or highly suspected of autoimmune diseases (AID) of the 15 patients, 11 patients accounting for 1.18% were diagnosed AID, including 6 CTD, 3 pSS, 1 RA and 1 pSS/PBC;4 patients were highly suspected as AID , including 3 suspected CTD and 1 suspected pSS.The titers concentration of the positive antibodies in patients with confirmed or suspected AID ≥ 3 times cut-off.Conclusions The positive rate of autoantibodies in individuals of physical examination is high , but there is clinical significance when the titers concentration of positive autoantibodies ≥ 3 times of the cut-off.Positive-autoantibodies patients with high-risk of autoimmune disease need professional clinician to provide follow-up, consulting and health education for early discovery, timely diagnosis, and proper treatment of AID.