ABSTRACT
Currently no validated diagnostic system for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is available. Therefore, diagnosing AAV is often challenging. We aimed to identify factors that lead to a clinical diagnosis AAV in ANCA positive patients in a teaching hospital in The Netherlands.In this study, all patients that tested positive for ANCA proteinase 3 (PR3) and/or myeloperoxidase (MPO) between 2005 and 2015 were analysed. Patients with a clinical diagnosis of AAV were compared with patients without a clinical diagnosis of AAV. Clinical symptoms and laboratory variables at presentation, including the ANCA titre, were collected for both patients with and without AAV. Clinical and laboratory variables related with AAV were investigated, using multivariable logistic regression.Two hundred thirty seven consecutive patients with a positive ANCA were included, of whom 119 were clinically diagnosed with AAV. Of the 118 ANCA positive patients without AAV, 87 patients had an alternative diagnosis, including inflammatory bowel disease (nâ=â24), other rheumatic diseases (nâ=â23), infection (nâ=â11), malignancy (nâ=â4), and other diagnoses (nâ=â25). In a multivariable regression model, a high ANCA titre (odds ratio [OR] 14.16, 95% confidence interval [CI] 6.93-28.94) and a high number of affected organ systems (OR 7.67, 95% CI 3.69-15.94) were associated with AAV.MPO and PR3 ANCA can be positive in a variety of diseases that mimic AAV. A higher ANCA titre and multiple affected organ systems may help to discriminate between AAV and other systemic illnesses in anti-PR3 and anti-MPO positive patients. A diagnostic scoring system incorporating these factors should be considered.
Subject(s)
Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/diagnosis , Antibodies, Antineutrophil Cytoplasmic/analysis , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/epidemiology , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/metabolism , Diagnosis, Differential , Female , Follow-Up Studies , Humans , Incidence , Male , Middle Aged , Netherlands/epidemiology , Reproducibility of Results , Retrospective StudiesABSTRACT
Leukopenia has a high incidence and is usually a reason for additional testing. Benign ethnic neutropenia is a relatively common cause of neutropenia in the negroid population. It can be the cause of aberrant laboratory results in negroid patients. A 55-year-old woman from Ghana was referred to the outpatient clinic because of malaise, leukopenia and neutropenia. Viral infection, haematological malignancy, auto-immune disease and vitamin deficiency were considered, but could not be confirmed by additional testing. Upon further investigation, the neutropenia in this patient was found to have existed for years. Moreover, our patient's son also had asymptomatic leukopenia. Therefore, benign ethnic neutropenia was considered the most likely diagnosis. Serological analysis of the patient's erythrocytes revealed the absence of Duffy (Fy) blood group antigens Fy(a) and Fy(b), which is associated with benign ethnic neutropenia.
Subject(s)
Black People , Neutropenia/diagnosis , Neutropenia/ethnology , Female , Ghana/ethnology , Humans , Leukopenia/diagnosis , Middle AgedABSTRACT
A high CD4(+)/CD8(+) ratio in bronchoalveolar lavage fluid is indicative for the diagnosis pulmonary sarcoidosis but this ratio only does not fully discriminate pulmonary sarcoidosis from other interstitial lung diseases. Recently, the integrin CD103 has been implicated in the diagnostic evaluation of sarcoidosis. CD103 is expressed on intraepithelial lymphocytes in mucosal areas, including bronchi, and is possibly involved in the retention of lymphocytes to the mucosa. The Dutch BAL working party initiated an investigation to evaluate the diagnostic value of relative number of CD103 expressing CD4(+) T-lymphocytes in the BAL fluid of patients with a variety of interstitial lung diseases. The expression of CD103 was examined on bronchoalveolar lavage cells from 119 patients including 56 patients with pulmonary sarcoidosis. We redefined criteria for alveolar CD4(+) T-cell lymphocytosis and for the relative enumeration of CD103 expressing CD4(+) T-lymphocytes in the BAL fluid. Our data demonstrate that the combined use of the CD103(+)CD4(+)/CD4(+) ratio (<0.2) and the BAL CD4(+)/CD8(+) ratio (>3) or the relative alveolitis CD4(+)/CD8(+) BAL/PB ratio (>2) provides a specific tool for discriminating sarcoidosis, also without a clear CD4(+) alveolitis, from other interstitial lung diseases.
