Epidermolysis bullosa acquisita (EBA) is an autoimmune-mediated subepidermal bullous disease in which the target of the autoantibodies is type VII collagen, a major component of anchoring fibrils. The purpose of this study was to evaluate the complement-fixing abilities and IgG subclass distribution of autoantibodies in EBA, and to also attempt to investigate the relation between inflammation, complement fixation and IgG subclass distribution in EBA patients. Only 2 sera of 18 patients (11%) showed weak complement-fixing abilities. IgG1 and IgG4 were the most frequently and intensely stained IgG subclasses in EBA sera. We could not find any relationship between the clinico-pathologic types, complement-fixing abilities and IgG subclasses in EBA. These results suggested that complement activation may not be a key factor of bulla formation in EBA.
Adult ; Autoantibodies/classification* ; Complement/immunology* ; Epidermolysis Bullosa Acquisita/immunology* ; Female ; Fluorescent Antibody Technique ; Human ; IgG/classification* ; Male ; Middle Age

Systemic lupus erythematosus (SLE) is a prototype for multi-system, autoimmune diseases of unknown etiology, characterized by the production of autoantibodies. SLE can involve any organ system of the body with constitutional symptoms, including musculoskeletal, skin, renal, neuropsychiatric, cardiovascular, respiratory and gastrointestinal systems. These wide spectra of disease manifestations have made disease classification difficult. American College of Rheumatology (ACR) proposed classification criteria for SLE for research purpose in 1982, which had been widely used for research purpose and not for diagnosis. In 1997, these criteria were updated with further recognition of antiphospholipid antibodies, but not validated. But ACR criteria didn't still meet the necessity for earlier diagnosis of SLE. In order to improve clinical relevance and incorporate new knowledge to the field of lupus immunology, the Systemic Lupus Erythematosus International Collaborating Clinics (SLICC), an international lupus expert group dedicated to clinical research on lupus, revised the ACR systemic lupus classification criteria in 2012. The new 2012 SLICC criteria were validated using a large set of patient scenarios rated by experts. The history and diagnostic utility of SLE criteria are covered in this review.
Allergy and Immunology ; Antibodies, Antiphospholipid ; Autoantibodies ; Autoimmune Diseases ; Classification* ; Diagnosis ; Humans ; Lupus Erythematosus, Systemic* ; Rheumatology ; Skin

OBJECTIVEA study on the value of antimitochondrial antibody (AMA) and its subtypes anti-M2, anti-M4, and anti-M9 in diagnosing primary biliary cirrhosis (PBC).

METHODSAntimitochondrial antibody was detected by indirect immunofluorescence and anti-M2, anti-M4 and anti-M9 by Western blotting. AMA and anti-M2 of 78 PBC patients, of 35 non-PBC hepato-biliary disease patients and 20 healthy controls were studied and anti-M2, anti-M4 and anti-M9 were studied in 30 of the 78 PBC patients.

RESULTS96.2% (75/78) of PBC patients were AMA positive and 94.9% (74/78) of PBC patients were anti-M2 positive. Only three among the 35 non-PBC patients were positive for AMA (one with very low titre). None of the 35 non-PBC patients was anti-M2 positive. AMA and anti-M2 were negative in all the healthy controls. Among the 30 anti-M2 positive patients, 16 patients were anti-M4 positive (16/30, 53.3%) and 4 patients were anti-M9 positive (4/30, 13.3%).

CONCLUSIONAMA and its subtypes (special anti-M2) are important sero-immunological markers for the diagnosis of PBC.

Autoantibodies ; blood ; classification ; Female ; Humans ; Liver Cirrhosis, Biliary ; diagnosis ; immunology ; Male ; Mitochondria, Liver ; immunology

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of autoimmune muscle diseases with systemic involvement. Patients with IIM present with varying degrees of muscle disease, cutaneous manifestations, and internal organ involvement. The diagnosis and classification of IIM is based primarily on the classification system composed of clinical features, laboratory value and muscle biopsy. In addition, the identification and characterization of myositis-related autoantibodies can help diagnosis and classification. Recently, many studies have also demonstrated that the physician can define the clinical syndromes, establish treatment strategy and predict outcomes based on the patients' myositis-specific autoantibodies (MSA) and myositis-associated antibodies (MAA) profiles. MSAs are found exclusively in IIMs and facilitate the identification of subsets of patients with relatively homogeneous clinical features. MAAs are frequently found in association with other MSA; however, they may also be detected in various connective diseases.
Antibodies ; Antibodies, Antinuclear ; Autoantibodies ; Biopsy ; Classification ; Dermatomyositis ; Diagnosis ; Humans ; Myositis ; Polymyositis

PURPOSE: With rising obesity rates in children, it is increasingly difficult to differentiate between type 1 and type 2 diabetes mellitus (T1DM, T2DM) on clinical grounds alone. Using C-peptide as a method of classifying diabetes mellitus (DM) has been suggested. This study aimed to find a correlation between fasting C-peptide level and DM types in children and adolescents. METHODS: A total of 223 diabetic children, newly diagnosed at 5 hospitals between January 2001 and December 2012, were enrolled in this study. Initial DM classification was based on clinical and laboratory data including fasting C-peptide at diagnosis; final classification was based on additional data (pancreatic autoantibodies, human leukocyte antigen type, and clinical course). RESULTS: Of 223 diabetic children, 140 were diagnosed with T1DM (62.8%) and the remaining 83 with T2DM (37.2%). The mean serum C-peptide level was significantly lower in children with T1DM (0.80 ng/mL) than in children with T2DM (3.91 ng/mL). Among 223 children, 54 had a serum C-peptide level <0.6 ng/mL; they were all diagnosed with T1DM. The proportion of children with T2DM increased in accordance with C-peptide level. Forty-nine of 223 children had a C-peptide level >3.0 ng/mL; 48 of them (97.9%) were diagnosed with T2DM. CONCLUSION: In this study, we found that if the C-peptide level was <0.6 ng/mL at diagnosis, T2DM could be excluded; if C-peptide level was >3.0 ng/mL, a T1DM diagnosis is unlikely. This finding suggests that serum fasting C-peptide level is useful for classifying DM type at the time of diagnosis in youth.
Adolescent* ; Autoantibodies ; C-Peptide* ; Child* ; Classification* ; Diabetes Mellitus* ; Diabetes Mellitus, Type 2 ; Diagnosis ; Fasting* ; Humans ; Leukocytes ; Obesity

Systemic lupus erythematosus(SLE) is a disease of unknown etiology in which multiple organs are damaged by pathogenic autoantibodies and immune complexes. Neuropsychiatric manifestations in SLE were first described by Kaposi in 1872. These are so diverse that they include psychosis, depression, stroke, seizure and cognitive dysfunction etc. These patients are frequently consulted for psychiatric evaluation. Neuropsychiatric manifestations in SLE are also among the leading causes of morbidity and mortality and associated with poor long-term outcome. So it is essential to recognize and intervene these symptoms early. But the clear diagnostic criteria for CNS involvement in SLE have not been formulated, and diversity and fluctuation of illness make it difficult to confirm it. The authors reported three cases of SLE with severe neuropsychiatric manifestations. These patients showed symptoms such as disorientation, auditory and visual hallucibation, delusion and mood instability. They became frequently impulsive and violent and had risks to injure themselves or others. Although CNS involvement in SLE is not well known, we reviewed the pathogenesis, classification, diagnosis, clinical manifestation and treatment of them.
Antigen-Antibody Complex ; Autoantibodies ; Classification ; Delusions ; Depression ; Diagnosis ; Humans ; Lupus Erythematosus, Systemic* ; Mortality ; Psychotic Disorders ; Seizures ; Stroke

Latent autoimmune diabetes in adults (LADA), presenting with a similar phenotype of type 2 diabetes at early stage, belongs to the slowly progressive subtype of autoimmune type 1 diabetes. LADA differs from classic juvenile-onset type 1 diabetes in which its autoimmune destructive process of islet beta-cells is much slower, so LADA may serve as a human model of autoimmune type 1 diabetes. Although no international standardized criteria for the diagnosis of LADA has been established, it should be noted that LADA has some specific features in clinical characteristics, susceptible genotypes, cellular and humoral immune markers, as well as islet pathology. Presence of islet autoantibodies is necessary for the diagnosis of LADA. Early insulin intervention may preserve residual islet beta-cell function in LADA. The different pathological manifestations of LADA with different autoantibody titers can help throw light on the autoimmune process, laying foundation of prevention or even cure of type 1 diabetes.
Adult ; Autoantibodies ; blood ; Diabetes Mellitus, Type 1 ; classification ; diagnosis ; drug therapy ; Humans ; Insulin ; therapeutic use ; Islets of Langerhans ; immunology

OBJECTIVETo compare the clinical characteristics between type 2 diabetes mellitus (T2DM) and latent autoimmune diabetes in adults (LADA) with different titers of glutamic acid decarboxylase autoantibody (GADA) and to define the two distinct subtypes of LADA.

METHODSSera of 750 patients with an initial diagnosis of T2DM from central south of China were screened for GADA using a radioligand assay. The distribution and frequency of GADA levels were described. Two hundred and ninety-five patients were divided into the T2DM group (n = 233) and the LADA group (n = 62) to compare the age of onset, body mass index, HbA(1c), C-peptide, hypertension, dyslipidemia and chronic diabetic complications. Furthermore, LADA patients with different GADA titers were subdivided to analyze the same indexes as the above.

RESULTSThe prevalence of LADA (defined as GADA > or = 0.05, namely GADA positive) was 9.7% in the 750 initially diagnosed type 2 diabetic patients. Compared with T2DM, LADA patients were younger at their ages of onset, had lower C-peptide and body mass index, and also had less cases with hypertension and with dyslipidemia. However, only patients with high titer of GADA had poorer beta cell functions and less diabetic complications compared to T2DM and low GADA titer of LADA patients. Patients with low GADA titer were similar to T2DM patients, except that they were prone to develop ketosis more frequently.

CONCLUSIONSTwo clinically distinct subtypes of LADA can be identified by GADA levels in patients initially-diagnosed as type 2 diabetes. Patients with high titer of GADA (GADA > or = 0.5) subsequently develop more insulin dependency, which are classified as LADA-type 1; while those with lower GADA titer (0.05 < or = GADA < 0.5) and having clinical and metabolic phenotypes of type 2 diabetes are classified as LADA-type 2.

Adult ; Aged ; Aged, 80 and over ; Autoantibodies ; analysis ; Autoimmune Diseases ; classification ; immunology ; Diabetes Mellitus, Type 1 ; classification ; immunology ; Diabetes Mellitus, Type 2 ; classification ; immunology ; Female ; Glutamate Decarboxylase ; immunology ; Humans ; Male ; Middle Aged

Systemic sclerosis (SSc) is a connective tissue disease of unknown origin, which is characterized by fibrosis of the skin and internal organs, and endothelial and immunologic dysfunction. The presence of a wide range of symptoms renders disease classification difficult. Although recent studies have contributed to our understanding of this debilitating illness, well-validated classification criteria are required for accurate comparison between registries and clinical trials, to assess response to treatment, morbidity and prognosis. Given the emphasis placed upon early and aggressive treatment, the 1980 American College of Rheumatology (ACR) classification criteria are of limited utility with respect to early diagnosis of SSc and limited cutaneous SSc. Recently, the 2013 ACR/European League Against Rheumatism classification criteria for SSc were published for research and clinical practice purposes. These criteria include skin thickening, fingertip lesions, telangiectasia, abnormal nailfold capillaries, Raynaud's phenomenon, SSc-specific autoantibodies and pulmonary complications pertaining to vasculopathy, autoimmunity and fibrosis. These updated criteria should allow a greater number of patients to receive an early diagnosis of SSc.
Autoantibodies ; Autoimmunity ; Capillaries ; Classification* ; Connective Tissue Diseases ; Diagnosis ; Early Diagnosis* ; Fibrosis ; Humans ; Prognosis ; Registries ; Rheumatic Diseases ; Rheumatology ; Scleroderma, Systemic* ; Skin ; Telangiectasis

OBJECTIVE: Anti-neutrophil cytoplasmic antibody (ANCA) is an important marker for the diagnosis and the classification of rheumatic diseases and systemic vasculitis. If the autoantibodies that can be stained in the nucleus of neutrophil used for substrate of ANCA test, there's a need for its differential diagnosis from real p-ANCA. This paper focuses on digital image processing technique for the differentiation of p-ANCA without performing additional tests. METHODS: Positive ANCA results which showed mixed fluorescent pattern were transformed into digital image. Using Matlab (MathWorks, U.S.A.), we developed 2D to 3D transformation method and virtual tomography for the interpretation of mixed fluorescent pattern, and compared these results with ANA and anti-DNA test by indirect immunofluorescence (IIF) method using IT-AIT, IT-ANCA, and IT-DNA kit (ImmunoThink, Korea). RESULTS: By applying the 3D transformation method and virtual tomography to the results of ANCA test where combined antibodies exist, we were able to separate each different fluorescent pattern that were difficult to separate by manual reading. CONCLUSION: The new digital image analysis methods developed in this study displace some of the disadvantages of IIF method. Therefore, these methods can easily be applied to complex samples, and can allow rapid and accurate tests for rheumatic diseases and other autoimmune diseases.
Antibodies ; Antibodies, Antineutrophil Cytoplasmic* ; Antibodies, Antinuclear ; Autoantibodies ; Autoimmune Diseases ; Classification ; Diagnosis ; Diagnosis, Differential ; Fluorescent Antibody Technique, Indirect ; Image Processing, Computer-Assisted ; Neutrophils ; Rheumatic Diseases ; Systemic Vasculitis