Vitamin K deficiency bleeding in cholestatic infants with alpha-1-antitrypsin deficiency.

OBJECTIVE: Exclusively breastfed infants with unrecognised cholestatic jaundice are at high risk of a vitamin K deficiency (VKD) bleeding. It is presently unknown whether (the size of) this risk depends on the degree of cholestasis. Since alpha-1-antitrypsin deficiency (A1AD) induces a variable degree of cholestasis, we assessed the risk of VKD bleeding in infants with cholestatic jaundice due to A1AD. PATIENTS AND METHODS: Infants with a ZZ or SZ phenotype born in The Netherlands between January 1991 and December 2006 were identified from the databases of the five Dutch diagnostic centres for alpha-1-antitrypsin phenotyping and/or genotyping. We determined the risk of VKD bleeding upon diagnosis of A1AD in breastfed and formula fed infants and searched for correlations between serum levels of conjugated bilirubin and the risk of bleeding. RESULTS: A total of 40 infants with A1AD were studied. VKD bleeding was noted in 15/20 (75%) of breastfed infants, compared with 0/20 of formula fed infants with A1AD. The relative risk for VKD bleeding in breastfed versus formula fed infants was at least 15.8 (95% CI 2.3 to 108). Conjugated bilirubin levels at diagnosis did not correlate with the risk of VKD bleeding. CONCLUSIONS: The risk of VKD bleeding in breastfed infants with A1AD was high and did not correlate with serum level of conjugated bilirubin at diagnosis. A similar absolute risk was previously reported in breastfed infants with biliary atresia under the same prophylactic regimen. This confirms that-without adequate prophylaxis-the risk of VKD bleeding is uniformly high in exclusively breastfed infants with cholestatic jaundice, irrespective of underlying aetiology.

The prognosis and outcome of patients referred to an outpatient clinic for rheumatic diseases characterized by the presence of antinuclear antibodies (ANA).

To evaluate if patients with symptoms related to the musculoskeletal system, characterized by the presence of ANA, are prone to develop SLE or other specific rheumatic diseases, a follow-up study was started to investigate all patients who for the first time visited the outpatient clinic of the Department of Rheumatology in the period from 1983 to 1986 and who had detectable ANA. Patients with anti-dsDNA antibodies were excluded from evaluation. In total 65 patients could be included in the study, with a mean duration of follow-up of 9.3 years (range 2-16 years). During follow-up a specific rheumatic diagnosis could be established in 38 patients, on 75% of the patients within 2 years of follow-up, and in 90% within 5 years. Five patients developed a non-rheumatic disease. For the remaining 22 patients, diagnosis was not conclusive. These patients without a conclusive diagnosis had a mild clinical picture, which remained stable during follow-up. In conclusion 58% of patients presented with rheumatic symptoms and detectable ANA developed an overt rheumatic disease, usually within the first 5 years of follow-up.

Nephelometric measurements of human IgG subclasses and their reference ranges.

IgG subclass measurements are generally performed with the radial immunodiffusion (RID) technique. With this method, results are obtained after an incubation period of 48-72 hours. We developed nephelometric assays on the Behring Nephelometer Analyzer (BNA) that allow a quantification of IgG subclass concentrations in a large number of samples quickly (less than 15 minutes for a complete IgG subclass profile) and reproducibly (intra-assay variation 2.5-5.5%, interassay variation 3.4-6.0% and inter-lab variation 5.4-10.3%). The nephelometric method was compared with the RID technique by analyzing the IgG subclass levels in sixty selected samples. For all IgG subclasses identical results and high correlation coefficients (r > 0.93) were found. In addition, the detection limits of the nephelometric method for all four IgG subclasses were identical or lower than those of the RID technique. Furthermore, the interlab variations of the nephelometric IgG subclass assays are lower than those of the RID method. However, the major advantages of the nephelometric assay are the speed, the minimal workload (automated IgG subclass determinations) and the possibility for automated bidirectional data transmission. Recently we have established new reference ranges for the human IgG subclasses in sera of adults and children. In order to validate these reference values we have measured the IgG subclasses in sera from 112 healthy children with the nephelometric method. In 1992, more than 2000 patient sera were tested by the nephelometric assay. A predominance of IgG2 abnormality was observed. In 9.8% of these sera the IgG2 concentration was decreased. Elevated IgG2 concentrations were found in 1.9% of the sera. Furthermore, the sum of the quantitated four IgG subclasses was similar to that of total IgG (less than 20% difference).

'Horoscope effect' not only for seasonal but also for non-seasonal allergens.

We report on the relation between the month of birth and the chance of developing an IgE antibody response as found in a study sample of 150,000 subjects. Our results confirm that for the three seasonal allergens birch pollen, grass pollen and house dust mite, an increased relative risk was found for subjects born up to 3 months before the main season for that allergen in The Netherlands. For cat and dog allergy an increased relative risk was found from November to January, perhaps reflecting increased exposure to these pets during the winter. Surprisingly, however, also for egg white and cow's milk a clearly increased relative risk was found from November to January and a decreased relative risk in May. These data support the hypothesis of a 'sensitive' period in the first months of life during which allergen exposure is more likely to prime for an allergy later in life. The results with the non-seasonal allergens suggest that another seasonal factor exists which early in life assists (or prevents) priming by allergen.

Analysis of intraarticular fibrinolytic pathways in patients with inflammatory and noninflammatory joint diseases.

OBJECTIVE: Intraarticular activation of the fibrinolytic system has been suspected to occur in patients with arthritis. We undertook the present study to investigate the relation of this activation to clinical symptoms, and the molecular pathways involved. METHODS: We quantitatively assessed levels of plasmin-alpha 2-antiplasmin (PAP) complexes in synovial fluid (SF) from 25 patients with rheumatoid arthritis (RA), 7 with seronegative spondylarthropathy (SSA), and 10 with osteoarthritis (OA), and conducted an analysis to determine the plasminogen-activating pathway via which these complexes were generated. In addition, we studied the relationship of intraarticular fibrinolysis to clinical and biochemical parameters. RESULTS: All patients studied had increased SF levels of PAP complexes. Levels in patients with RA and SSA were slightly higher than those in patients with OA. These complexes were probably formed by activation of urokinase-type plasminogen activator (u-PA), and not tissue-type plasminogen activator (t-PA), since SF levels of both u-PA antigen and u-PA-plasminogen activator inhibitor (PAI) complexes were increased in 27 of the 42 patients. Conversely, SF levels of t-PA were below normal in all but 1 patient. In some patients, activation of factor XII presumably also contributed to plasminogen activation in SF, since levels of factor XIIa-C1 inhibitor in SF were increased in 8 of the 42 patients and correlated, as did u-PA-PAI levels, with levels of PAP complexes. Several of the parameters of fibrinolysis in SF, particularly u-PA antigen and u-PA-PAI-1 complexes, were found to correlate with clinical and biochemical parameters. CONCLUSION: Our results suggest that plasminogen is frequently activated in the joints of patients with inflammatory or noninflammatory arthropathy and that this activation mainly occurs via a u-PA-, and in some cases also via a factor XII-, dependent pathway. The possible relation of this activation process to stimulation of synovial cells by cytokines is discussed.

Beta 2 microglobulin in tear fluid from patients with primary Sjögren's syndrome.

beta 2 Microglobulin concentration in tear fluid was measured in 35 patients with primary Sjögren's syndrome (SS), in 28 normal control subjects matched for age and sex, and in 18 patients with arthralgias or myalgias and sicca complaints, in whom the diagnosis primary SS had been excluded. Increased beta 2 microglobulin concentrations were found in the patients with SS, but no correlation was found with the duration of the disease, age, or tear fluid production. Tear fluid beta 2 microglobulin determinations may be useful as an adjunctive diagnostic test for primary SS.

Predominant role of neutrophils in the inactivation of alpha 2-macroglobulin in arthritic joints.

We studied the state of alpha 2-macroglobulin (alpha 2M), an important inhibitor of cartilage-degrading proteinases, in relation to activation of neutrophils in 82 patients with several types of arthritis, including 52 with rheumatoid arthritis and 11 with osteoarthritis. Levels of total inactive alpha 2M (i alpha 2M), which comprises alpha 2M complexed to proteinases and alpha 2M inactivated by oxidation or hydrolysis, were measured with a monoclonal antibody specific for i alpha 2M. In addition, levels of alpha 2M complexed to proteinases were quantitated with specific assays. Neutrophil activation was assessed by measuring elastase-alpha 1-antitrypsin complexes and lactoferrin. In 83% of the 82 patients tested, the synovial fluid (SF) to plasma ratio of i alpha 2M exceeded 1, indicating an intraarticular generation. Levels of i alpha 2M significantly correlated with neutrophil numbers (P less than 0.0005) and with levels of elastase-alpha 1-antitrypsin complexes and of lactoferrin (P less than 0.00001 for both). Moreover, part of i alpha 2M consisted of alpha 2M complexed to elastase-like and chymotrypsin-like proteinases, presumably, neutrophil elastase and cathepsin G, respectively. However, the amount of i alpha 2M was approximately 10-fold larger than the amount complexed to these proteinases. In vitro inactivation of alpha 2M by activated neutrophils was only partly inhibitable by eglin C, a specific inhibitor of both elastase and cathepsin G. Release of reactive oxygen species was presumably responsible for the additional inactivation of alpha 2M, because eglin C completely abolished the inactivation of alpha 2M by cell-free supernatant of activated neutrophils. Thus, our results suggest a predominant role of neutrophils in the inactivation of alpha 2M in the SF of patients with inflammatory joint diseases. However, this inactivation could be explained only in part by the release of neutrophilic proteinases. We propose that the inactivation of alpha 2M in SF was due to the concerted action of both reactive oxygen species and lysosomal proteinases.

Systemic lupus erythematosus--changing disease patterns in the disease course. Dutch experience with 110 patients studied prospectively.

The aim of this study was to investigate which patients with systemic lupus erythematosus (SLE) are prone to develop more than one exacerbation, and to establish the variability in the clinical symptoms during exacerbations as compared with the initial symptoms of the disease. At disease origin, photosensitivity, pleuritis and Raynaud's phenomenon were slightly increased in the patients with a stable disease, while pericarditis was rarely seen in patients with a remitting disease course. In this prospective study it was clearly shown that during the disease course, depending on the exacerbation frequency, an increasing number of organs were involved. Striking features were the increase in haematological abnormalities in the third exacerbation, and the fact that psychosis and seizures did not recur in the second exacerbation when they were diagnosed in the preceding period. We also showed that symptoms seen in an exacerbation may be quite different from those seen in a previous exacerbation.

Significance of low molecular weight C1q in systemic lupus erythematosus.

The significance of high serum concentrations of low molecular weight C1q (LMW-C1q) in patients with systemic lupus erythematosus (SLE) was studied. Concentrations of LMW-C1q were increased in SLE, but not in rheumatoid arthritis or acute poststreptococcal glomerulonephritis. Concentrations of LMW-C1q in SLE serum samples correlated with titres of anti-dsDNA and were inversely related to concentrations of normal C1q and C3. Serial studies in six patients, who had rising anti-dsDNA titres and who developed a major exacerbation requiring admission to hospital, showed that LMW-C1q increased in parallel with anti-dsDNA, reaching peak values of more than 2000% of normal just before or at the time of clinical relapse and decreasing during convalescence. Most marked increases in LMW-C1q were noted in the three patients in whom C1q concentrations remained normal, whereas increases were less in the three patients who had strongly depressed concentrations of normal C1q. A study of C1q biosynthesis by macrophages cultured from patients with SLE and high serum concentrations of LMW-C1q did not show impaired secretion of normal C1q in favour of LMW-C1q, but indicated that serum concentrations of LMW-C1q may reflect the synthetic rate of C1q in vivo. The results show that increased serum concentrations of LMW-C1q may be helpful in diagnosing SLE and suggest that serial determination of LMW-C1q in serum may have predictive value in monitoring patients with SLE.

Systemic lupus erythematosus. I. Outcome and survival: Dutch experience with 110 patients studied prospectively.

This report presents an analysis of the cumulative survival in 110 well defined patients with systemic lupus erythematosus (SLE) who were followed up over a prolonged period of time. Special attention was paid to possible differences between patients who died and those who were still alive at the end of the study. Of the 110 patients with SLE, 96 (87%) were still alive after 10 years; the cumulative survival for men was 69% (11/16) and for women 90% (85/94). Patients who never developed a new exacerbation after the diagnosis for SLE had been established had a 10 year survival of 100%; for patients with one, two, or three exacerbations the 10 year survival was 91%, 69%, and 33% respectively. From these prospective studies it was found that the exacerbation frequency is most closely related to survival. Disease symptoms of renal involvement or neurological involvement, or both, present at the onset or at the moment the SLE diagnosis was established, were predominantly seen in patients who died during the follow up.

Systemic lupus erythematosus. II. Observations on the occurrence of exacerbations in the disease course: Dutch experience with 110 patients studied prospectively.

The incidence of exacerbations in the disease course was investigated in 110 patients with systemic lupus erythematosus (SLE) who were studied prospectively at our institute for lupus research. At the time of disease onset and diagnosis the male patients were much older than the female patients (about 10 years); exacerbation frequency during follow up was increased in the male patients. The follow up data showed that if a patient with SLE was prone to develop an exacerbation this mostly took place within the first five years of follow up. It could be calculated that after fulfilling the American Rheumatism Association criteria only 56% (62/110) of the patients developed a subsequent exacerbation. Features at the time of diagnosis, distinguishing those patients who developed a subsequent exacerbation from those who did not, were haemolytic anaemia, the presence of anti-Sm antibodies, and a falsely positive serological test for syphilis. At the time of diagnosis, however, the prevalences of these features were low; for haemolytic anaemia, anti-Sm antibodies, and a falsely positive serological test for syphilis they amounted to 40%, 5%, and 12% respectively.

The effect of reduction of IgM on the quantitative determination of IgM by radial immunodiffusion and turbidimetry.

The behaviour of different IgM proteins in radial immunodiffusion was investigated. In agreement with earlier findings differences were observed between various IgM preparations, which disappeared after reduction of IgM. The amount of IgM in several standard sera, that are used for the quantitative determination of IgM, was measured by radial immunodiffusion after reduction of IgM, and was found to be lower than hitherto accepted. It was observed that it was not necessary to perform reduction of IgM before its quantitation when a turbidimetric immunoassay was used. We conclude that (1) the standard sera that are used for the determination of IgM have to be calibrated in radial immunodiffusion after reduction of IgM and (2) the absolute amount of IgM in sera is about 0.6 times the amount that is commonly accepted.