Nódulo reumatóide pulmonar há 2 anos, sem desenvolvimento de artrite reumatóide em paciente masculino - Relato de caso / Pulmonary rheumatoid nodule for 2 years, without development of rheumatoid arthritis in male patient - Case report

A artrite reumatóide (AR) se caracteriza como doença auto-imune, sistêmica e de causa desconhecida. Apesar das manifestações osteoarticulares merecerem maior atenção, a AR, como doença sistêmica, pode ter acometimento visceral. O envolvimento pulmonar inclui nódulos parenquimatosos, envolvimento intersticial e doença em via aérea. O caso relatado apresenta relevância, uma vez que se refere ao aparecimento do nódulo pulmonar reumatóide sem manifestação articular como extra-articular da doença. Nódulos pulmonares reumatóides como manifestação inicial de AR são eventos raros e de interesse científico

Increased Cytokeratin 19 Fragment Levels Are Positively Correlated with Adenosine Deaminase Activity in Malignant Pleural Effusions from Adenocarcinomas

Adenosine deaminase (ADA) and cytokeratin 19 (CK19) are known pleural biomarkers. Although ADA in humans functions mainly in the immune system, it also appears to be associated with the differentiation of epithelial cells. Keratin filaments are important structural stabilizers of epithelial cells and potent biomarkers in epithelial differentiation. This study aimed to investigate the simultaneous presence of the ADA enzyme and CK19 fragments to assess epithelial differentiation in malignant and benign pleural fluids. Diagnosis of the cause of pleural effusion syndrome was confirmed by means of standard examinations and appropriate surgical procedures. An ADA assay, in which ADA irreversibly catalyzes the conversion of adenosine into inosine, was performed using a commercial kit. The CK19 assay was performed using a CYFRA 21-1 kit, developed to detect quantitative soluble fragments of CK19 using an electrochemiluminescence immunoassay. One hundred nineteen pleural fluid samples were collected from untreated individuals with pleural effusion syndrome due to several causes. ADA levels only correlated with CK19 fragments in adenocarcinomas, with high significance and good correlation (rho = 0.5145, P=0.0036). However, further studies are required to understand this strong association on epithelial differentiation in metastatic pleural fluids from adenocarcinomas

Diagnostic Accuracy with Total Adenosine Deaminase as a Biomarker for Discriminating Pleural Transudates and Exudates in a Population-Based Cohort Study

Background. An initial step in the evaluation of patients with pleural effusion syndrome (PES) is to determine whether the pleural fluid is a transudate or an exudate. Objectives. To investigate total adenosine deaminase (ADA) as a biomarker to classify pleural transudates and exudates. Methods. An assay of total ADA in pleural fluids (P-ADA) was observed using a commercial kit in a population-based cohort study. Results. 157 pleural fluid samples were collected from untreated individuals with PES due to several causes. The cause most prevalent in transudate samples (21%, n=33/157) was congestive heart failure (79%, 26/33) and that among exudate samples (71%, n=124/157) was tuberculosis (28.0%, 44/124). There was no significant difference in the proportion of either sex between the transudate and exudate groups. The median values of P-ADA were significantly different (P<0.0001) between both total exudates (18.4 U/L; IQR, 9.85-41.4) and exudates without pleural tuberculosis (11.0 U/L; IQR, 7.25-19.75) and transudates (6.85; IQR, 2.67-11.26). For exudates, the AUC was 0.820 (95% CI, 0.751-0.877; P<0.001), with excellent discrimination. The optimum cut-off point in the ROC curve was determined as the level that provided the maximum positive likelihood ratio (PLR; 14.64; 95% CI, 2.11-101.9) and was22.0 U/L. For transudates, the AUC was 0.8245 (95% CI, 0.7470-0.9020; P<0.0001). Internal validation of the AUC after 1000 resamples was evaluated with a tolerance minor than 2%. The clinical utility was equal to 92% (95% CI, 0.84 to 0.96, P<0.05).Conclusions. P-ADA is a useful biomarker for distinguishing pleural exudates from transudates