Expression and diagnostic utility of anti-cyclic citrullinated peptide antibodies in juvenile idiopathic arthritis

Juvenile idiopathic arthritis [JIA] is a clinically heterogeneous group of arthritis occurring in children. Anti-cyclic citrullinated peptide [anti-CCP] antibodies have been recently included in the revised diagnostic criteria for adult onset rheumatoid arthritis. Its diagnostic value in JIA is still debatable. The study is aimed to investigate the expression and diagnostic utility of anti-CCP antibodies in pediatric JIA in relationship to its various clinical phenotypes. Forty children and adolescents [13 males, 27females] with JIA as well as 35 healthy children were enrolled in this cross-sectional study. Serum anti-CCP antibodies were determined by enzymatic immunoassay and its expression was statistically correlated to clinical, laboratory, and radiological data of the patients. Anti-CCP antibodies were positive in 8 [20%] patients while not expressed in the control group. Seven out of the 8 positive cases [87.5%] had polyarticular JIA and only one patient [12.5%] had the oligoarticular onset variety. A significant positive correlation was elicited between the anti-CCP antibody levels and the number of tender joints [r= 0.39], swollen joints [0.68] and disease duration [r = 0.59]. Radiographic erosive arthritis was found in 8 patients with positive anti-CCP antibodies; 7 of whom [87.5%] suffered the polyarticular subtype and only one patient [12.5%] had the oligoarticular subtype. All the rheumatoid factor [RF] seropositive patients had positive anti-CCP antibody as well as radiographic erosive arthritis. The overall anti-CCP antibody diagnostic value in our series showed a sensitivity and specificity of 20% and 100% respectively and the positive and negative predictive values were 100%, and 52.2%, respectively. Anti-CCP antibodies have a low sensitivity but high specificity in patients with JIA with a significant relationship to clinical and radiologic severity especially in RF seropositive cases. It may thus have a diagnostic and/or prognostic utility in severe polyarticular onset disease

Comparative diagnostic methods of tuberculosis in blood samples

Despite the availability of effective preventive measures and chemotherapy, the prevalence of tuberculosis [TB] is increasing in the developing world and in much of the industrialized world as well. Children are among the most vulnerable and the most difficult to diagnose with tuberculosis. Early and precise diagnosis of childhood tuberculosis is necessary in order to prevent mortality and morbidity and unjustified chemotherapy. One of the main objectives of the research in the field of mycobacteriology is the development of new methods that will improve and expedite the diagnosis and treatment of tuberculosis and other mycobacterial infections. HealthTech, in collaboration with DynaGen, Inc., in the United States, developed the MycoDotTM serological assay. Several techniques have been developed to improve the diagnosis of tuberculosis including newer radiometric methods; DNA probes mycolic acid chromatography polymerase chain reaction. We aimed in our work to diagnose active tuberculosis either pulmonary or extra pulmonary by different new diagnostic methods. In this study included 58 children ranged from 5 to 7 years old and suspected to have tuberculosis, based on the findings of history taking, clinical examination, PPD skin test, chest X-ray, and sputum examination by Zeil-Nielsen staining for acid fast bacilli. These patients were classified into four classes class 0: no known recent exposure, no infection [PPDnegative], no disease; class I: latent infection as defined by a positive PPD [>/= 10 mm in duration] and no clinical or radiographic evidence of active TB; class II: active TB confirmed by positive clinical pictures and radiographic evidence of active TB with positive sputum staining; Class III: PPD-positive [>/= 5 mm in duration] with evidence of past disease by history or compatible chest radiograph [e.g., upper lobe fibronodular disease] but negative sputum smear [treated patients]. All patients sera were subjected to TB identification by rapid test and MycoDot tests and PBMC separated from blood for PCR reaction. The positive results of the three tests for diagnosis of TB in the four groups of classes were detected as followings: By PCR the four classes were diagnosed as: Class 0 [5.3%], Class I [50%], Class II [70%] and Class III [14.3%]. By MycoDot diagnosis of the four groups was as: Class 0 [0%], Class I [4.5%], Class II [50%] and Class III [0%]. Diagnosis of the four groups by +ve rapid test was as: Class 0 [0%], Class I [0%], Class II [30%] and Class III [0%]. As a conclusion, PCR is a sensitive and rapid method for detection of latent and active TB within few hours, while in anti-LAM IgG was quite specific detection of active disease. The assay can be performed without sophisticated instrumentation with minimal training, which make the assay for random detection of active TB