PubMed Health⌕ Search

Biomedical subjects

G Mariën

Publications and source records attributed to G Mariën.

10 recordsLinked to original sources
PubMed2000

Screening for autoantibodies to SS-A/RO by indirect immunofluorescence using HEp-2000 cells.

We evaluated indirect immunofluorescence (IF) using HEp-2000 slides, which are transfected with SS-A cDNA, for screening for anti-SS-A antibodies, by comparing it with counterimmunoelectrophoresis (CIE). A total of 2427 specimens were screened for IF reactivity and for SS-A precipitins, of which 1033 (43%) were negative on both IF and CIE. There were 1271 SS-A precipitin-negative specimens (52%) which were IF-positive but lacked the distinctive SS-A staining pattern. One precipitin-negative serum was IF-positive with the distinctive SS-A pattern in the HEp-2000 system. One hundred and twenty-two specimens (5%) were positive for anti-SS-A precipitins on CIE, 107 showed the distinctive SS-A fluorescence staining pattern, whereas 15 of these precipitin-positive samples (12%) were IF-positive but did not display the distinctive SS-A pattern on the transfected cells. Fourteen of the 15 samples in which the distinctive SS-A pattern was not observed displayed other significant antinuclear antibody (titre equal or >1:320) patterns. In conclusion, the presence of the typical 'distinctive' SS-A pattern on IF using the HEp-2000 slides is highly specific for the presence of autoantibodies to SS-A and has a sensitivity of 88% for detecting these antibodies.

Antibodies, Antinuclear↗
PubMed1998

Clinical spectrum associated with positive ANCA titres in 94 consecutive patients: is there a relation with PR-3 negative c-ANCA and hypergammaglobulinaemia?

OBJECTIVE: To calculate the positive predictive value (ppv) of cytoplasmic antineutrophil cytoplasmic antibodies (c-ANCAs) and anti-proteinase 3 (PR 3) antibodies for Wegener's granulomatosis (WG) and to evaluate their association with other diseases. METHODS: The clinical files of all 94 patients who had a positive c- or perinuclear (p)-ANCA test, or both, in the laboratory of the University Hospital, Leuven between April 1995 and March 1996 and who attended the Internal Medicine Department of the hospital were retrospectively studied. RESULTS: Of the 94 patients with ANCAs (fluorescence titre > or = 1/40), 57 were c-ANCA positive and 45 p-ANCA positive (eight were simultaneously c- and p-ANCA positive). Of the 57 c-ANCA positive patients, 23 had WG. The ppv for WG thus was 40%. This value did not increase by defining a higher threshold for a positive ANCA. There was not a good relation between ANCA titres and disease activity in the WG patients, nor was there a relation between anti-PR 3 antibody levels and WG disease activity. The ppv of anti-PR 3 antibodies for WG however was very high (85%). There was a positive correlation between the level of (hyper) gammaglobulinaemia and c-ANCA titres in those patients with final diagnoses not known to be associated with c-ANCA. Forty five patients had positive p-ANCAs. The largest group were those with inflammatory bowel disease (n = 20, of whom the majority had colitis ulcerosa or primary sclerosing cholangitis, or both); the great majority of these patients had no anti-myeloperoxidase antibodies. Vasculitis was present in eight patients, of whom two had WG (both were also c-ANCA positive). CONCLUSION: There is a low ppv of c-ANCAs for WG, caused by a high percentage of PR 3 negative, positive c-ANCA determinations, possibly related to hypergammaglobulinaemia. Anti-PR 3 antibodies have a high ppv for WG. However, neither c-ANCA titre, nor the level of anti-PR 3 antibodies correlated with the activity of the disease.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1995

Elimination of paraprotein interference in determination of plasma inorganic phosphate by ammonium molybdate method.

Phosphate concentrations were determined in 52 cases of paraproteinemia. The unmodified acidic ammonium molybdate method produced 19% spuriously high results. The false increase of phosphate concentration was attributable to formation of precipitate in the reaction mixture. The precipitate was formed by interaction between immunoglobulins and the unmodified acidic ammonium molybdate reagent. The magnitude of interference bore no relation to the type, concentrations, or isoelectric point of the paraproteins or to the presence or absence of free light chains. Diluting the sample to approximately 40 g/L total protein reduced but did not always eliminate the interference. In some cases paraprotein concentration as low as 8 g/L falsely increased plasma phosphate results. Apparently, only IgG and IgM but not IgA paraproteins produced the interference. Deproteination by ultrafiltration or by treatment with trichloroacetic acid removed the interference. The Kodak slide method and the new modified Boehringer Mannheim phosphate test were found to be interference-free. However, in some cases the latter new formulation is sensitive to substantial changes in ionic concentration of the reaction mixture.

Ammonium Sulfate↗
PubMed1994

Simultaneous macroamylasemia and macrolipasemia.

The first case of the simultaneous presence of macroamylasemia and macrolipasemia in a patient with gluten enteropathy (celiac disease) is described. Both macroenzymes were formed by association of polyclonal IgA with amylase and lipase. Both macroenzymes had molecular masses > 300 kDa.

Amylases↗
PubMed1990

Predictive value of bronchoalveolar lavage in pulmonary sarcoidosis.

We investigated whether analysis of cellular composition (including lymphocyte subsets) in bronchoalveolar lavage (BAL) fluid at the start of follow-up in patients with untreated sarcoidosis has any predictive value for further evolution of the disease. The outcome was evaluated by the chest roentgenograms, the lung volumes, and the single breath diffusing capacity for CO (DCO) after 22 to 36 months. In contrast to the general belief, patients who improved radiologically had a significantly higher T4 cell count (as percentage of BAL lymphocytes) (p less than 0.02) and a higher T4-T8 ratio in the initial BAL sample (9.3 vs 3.2; p less than 0.05) than those whose chest roentgenogram showed deterioration or remained unchanged. Total cell count and the percentage of lymphocytes in BAL fluid were not different between both groups. The change in DCO at the end of the follow-up period correlated positively with the baseline BAL T4 cells (Rs = 0.44; p less than 0.05) and with the BAL T4-T8 ratio (Rs = 0.51; p less than 0.03) and negatively with the baseline BAL T8 cells (Rs = -0.48; p less than 0.04). In only three patients progression of the disease necessitated steroid therapy, and they all had a low to normal T4-T8 ratio in the initial BAL sample. Bronchoalveolar lavage was repeated at least once in ten patients. Improvement of the chest roentgenograms in these patients was accompanied by a decrease of the BAL T4 cell count (as percentage of lymphocytes) and of the T4-T8 ratio. We conclude that a high lymphocyte count, a high T4 cell count (as percentage of lymphocytes), and a high T4-T8 ratio in BAL fluid reflect an intense alveolitis at the time of the procedure, but they are not indicators of poor prognosis on which therapeutic decisions can be based.

Bronchoalveolar Lavage Fluid↗
PubMed1986

Influence of common cold and of parenteral administration of influenza virus antigens on bronchoalveolar lavage cells.

We investigated in a pilot study on healthy young subjects whether a common cold or a vaccination with influenza virus antigens within 10 days influenced the number and subsets of inflammatory cells in the bronchoalveolar lavage (BAL) fluid. The total number of BAL-cells was about doubled in the common cold group, yet no consistent changes in overall cell distribution was found. Among BAL-lymphocytes the ratio of helper-inducer over suppressor-cytotoxic lymphocytes (THI/TCS) tended to be increased in both groups, due to a lower percentage of TCS-cells, which was significant in the vaccination group only. In the blood, on the contrary, the THI/TCS ratio was significantly decreased in both groups due to a drop in THI-cells; in addition, the proportions of E-Rosette (+) T-cells and of activated (Ia+) T-cells were slightly increased. In conclusion, only minor changes in inflammatory BAL-cells were observed, which, however, may interfere with the effects of other diseases.

Adult↗
PubMed1984

Alveolar T-cell subsets in pulmonary sarcoidosis. Correlation with disease activity and effect of steroid treatment.

Alveolar lymphocytes, obtained by bronchoalveolar lavage in 35 patients with sarcoidosis, were analyzed with monoclonal antibodies to lymphocyte subsets. Untreated patients had significantly higher percentages of Leu 3a (+) T helper-inducer cells (THI) and significantly lower Leu 2a (+) T cytotoxic-suppressor cells (TCS) within the alveolar lymphocyte population than did normal control subjects (p less than 0.002). The mean ratio of alveolar THI to TCS cells was 6.20 +/- 3.76 versus 1.44 +/- 0.54 in control subjects (p less than 0.002). Untreated patients had a percentual enrichment of THI cells among alveolar lymphocytes relative to blood (p less than 0.0002), whereas TCS cells in percent of lymphocytes were lower in alveolar lavage fluid than in blood (p less than 0.002). These shifts were not observed in the control subjects. Patients with high-intensity alveolitis (i.e., T cells constituted 28% or more of alveolar inflammatory cells) had significantly greater proportions of THI cells among alveolar lymphocytes than did those with low-intensity alveolitis (p less than 0.01). This percent of alveolar THI cells correlated positively with the number of lymphocytes and T cells in percent of alveolar cells (p less than 0.03), which both are indexes of disease activity. In untreated patients who were lavaged at least twice, a decrease in the THI/TCS ratio was found to accompany or precede radiologic and clinical improvement, but the initial THI/TCS ratio was not predictive of further evolution. Steroid treatment decreased the THI/TCS ratio with a marked increase in the proportion of TCS cells. These changes were independent of an effect on the number of alveolar lymphocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗