Therapeutic experience with infliximab in a patient with polyarticular juvenile idiopathic arthritis and uveitis

A pediatric patient with prolonged seronegative polyarticular juvenile idiopathic arthritis (JIA) and concomitant aggressive, anterior uveitis refractory to any conventional antirheumatic therapy was treated with infliximab. Arthritis and C-reactive protein (CRP) values showed prompt positive effects but, after 6 weeks, returned gradually to initial values despite ongoing therapy. In contrast, a more sustained therapeutic effect was observed on the uveitis, with increased visual acuity and reduced inflammatory signs of the affected eye. However, this benefit was also lost at week 30, after which infliximab had to be discontinued due to side effects. To conclude, in polyarticular seronegative JIA, infliximab showed a transient beneficial effect which was more pronounced on uveitis than arthritis.

Do chemokines spark autoimmunity in juvenile and adult rheumatic disease?

The recent increase in knowledge on chemokines contributes substantially to the understanding of autoimmune inflammatory diseases, as cell migration is an essential prerequisite for the local immune reaction. The purpose of this review is to summarize the essential functions of chemokines in immune activation and to examine their role(s) in the initiation and perpetuation of autoimmunity in juvenile idiopathic arthritis and adult rheumatic disease. The possible relevance of chemokines as therapeutical targets will be discussed.

Cystatin C, an early indicator for incipient renal disease in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic disease requiring potential nephrotoxic therapy with nonsteroidal antiinflammatory drugs (NSAIDs) and disease modifying antirheumatic drugs (DMARDs). The rationale of our study was to examine the renal status of patients suffering from prolonged RA by means of plasma cystatin C, a new parameter of renal function. Fifty-six patients affected with RA for more than 5 years, and treated with NSAIDs for more than 50 months, were included in the study. Besides conventional markers of renal function (i.e. plasma creatinine, estimated glomerular filtration rate, creatinine clearance), we analysed plasma cystatin C by an automated, nephelometric immunoassay on a Behring nephelometer. Sixty percent of the RA patients exhibited elevated levels of plasma cystatin C, whereas only three out of 56 patients showed an elevated plasma creatinine, even though the creatinine clearance was decreased in 57% of these patients. Cystatin C exhibited a by far better correlation with creatinine clearance than plasma creatinine. In conclusion, patients with prolonged RA for more than 50 months, show a disturbed renal function despite normal plasma creatinine. Elevated cystatin C indicates such incipient renal disease, and is, not least because of a simple, well reproducible technique, more recommendable for screening purposes than tedious clearance determinations.

Insulin is an independent correlate of plasma homocysteine levels in obese children and adolescents

OBJECTIVE

The aim of the study was to investigate whether anthropometric and metabolic risk factors for coronary heart disease (CHD) contribute to the variation in homocysteine levels in obese children and adolescents.

RESEARCH DESIGN AND METHODS

A total of 84 children and adolescents were assessed for fasting total homocysteine, methylenetetrahydrofolate reductase polymorphism (C677T mutation), folate and vitamin B12 status, and anthropometric and metabolic risk factors for CHD.

RESULTS

No significant sex differences were found for all available anthropometric and metabolic characteristics except for homocysteine, which was significantly higher in boys than in girls (7.1 vs. 6.3 micromol/l; P<0.05). After adjustment for age and sex, homocysteine correlated significantly with BMI, fat mass, percentage of fat mass, and insulin and showed an inverse correlation with folate levels. Homocysteine did not correlate with vitamin B12; total cholesterol; LDL, HDL, and VLDL; triglycerides; and glucose. BMI and fat mass correlated significantly with insulin and showed a significant inverse correlation with folate. We found no association between homocysteine and the C677T mutation. In multiple regression analyses, insulin was found to be the main correlate of homocysteine.

CONCLUSIONS

Our study demonstrates for the first time that insulin is a main correlate of homocysteine in obese children and adolescents and suggests that fat mass-associated hyper-insulinism may contribute to impairment of homocysteine metabolism in childhood obesity

[Peripheral lymphadenopathy in childhood--recommendations for diagnostic evaluation]

BACKGROUND

Enlargement of peripheral lymph nodes most commonly caused by a local inflammatory process is frequently seen in childhood. The aim of the present study was to analyze the most common causes of peripheral lymphadenopathy and to develop a simple algorithm for the primary diagnostic evaluation of peripheral lymph node enlargement in this age group.

PATIENTS

Between April and September 1999 87 unselected children (median age: 5 1/2 years) with peripheral lymphadenopathy were referred to the Department of Pediatrics, University of Graz, for further investigation.

RESULTS

EBV infection was diagnosed in 20 (23.0%) children. 19 (21.8%) patients had acute bacterial lymphadenitis. In 21 (24.1%) patients lymph node enlargement was classified as "post/parainfectious (viral)". Four patients each had toxoplasmosis and cat scratch disease. In 11 (12.6%) patients neither physical nor laboratory examinations revealed pathologic results. Among the remaining 8 children sarcoidosis and Hodgkin disease was diagnosed in one patient each. Small, soft, mobile, nontender, cervical, axillary or inguinal lymph nodes do not require further investigations. In case of enlarged, tender lymph nodes with overlying skin erythema and fever diagnostic evaluation should include complete blood count, erythrocyte sedimentation rate and/or c-reactive protein level, supplemented by appropriate antibody testing (EBV, CMV, Toxoplasma gondii, Bartonella henselae). Firm, enlarged, painless lymph nodes which are matted together and fixed to the skin or underlying tissues necessitate a more detailed diagnostic evaluation in order to exclude malignant or granulomatous diseases.

CONCLUSIONS

Our study demonstrated that primary diagnostic evaluation of childhood peripheral lymphadenopathy is mainly based on clinical grounds. In most cases a small number of additionally performed laboratory tests allow to correctly identify the cause of the peripheral lymph node enlargement.

Synthesis pattern of matrix metalloproteinases (MMPs) and inhibitors (TIMPs) in human explant organ cultures after treatment with latanoprost and dexamethasone

PURPOSE

To determine changes in production of matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) in the ciliary body, the trabecular meshwork and the retinal pigment epithelium induced by both prostaglandins and corticosteroids.

METHODS

Explant organ cultures were removed by a scleral incision 3 mm posterior to the limbus. Retinal pigment epithelium was grown to confluence. Organ and cell cultures were treated with latanoprost and/or dexamethasone for 72 h. The activity of MMP-2, -3 and -9 was assessed using zymography. The synthesis pattern of MMPs and TIMP-1 and -2 was identified using immunostaining.

RESULTS

Treatment of explant organ cultures with 10 micrograms/ml of latanoprost induced a mean upregulation of MMP-2 by 36%, MMP-3 by 112% and MMP-9 by 156% as seen by zymography. Dexamethasone 500 nm reduced the amounts of secreted MMP-2 by 13%, MMP-3 by 69%. MMP-9 was not detectable in the media of corticosteroid-treated explant organ cultures. The addition of 10 micrograms/ml of latanoprost to dexamethasone-treated cultures increased MMP-2 by 14%, MMP-3 by 43% and MMP-9 by 49%. Using immunohistochemistry we found staining with antibodies against MMP-2, -3, -9 and TIMP-1 and -2 within the ciliary body, and only to a lesser degree in the trabecular meshwork. Latanoprost treatment caused an increase of 29% in MMP-2 (p < 0.0001), 98% in MMP-3 (p < 0.0001) and 108% in MMP-9 (p < 0.0001). Dexamethasone reduced the staining for MMP-2 by 32% (p < 0.0001), for MMP-3 by 33% (p < 0.0001) and for MMP-9 by 83% (p < 0.0001). Almost no change in staining for MMPs was detectable in the trabecular meshwork. Neither latanoprost treatment nor dexamethasone induced significant changes (p < 0.93) in the secretion of TIMPs. In the media of non-treated retinal pigment epithelium (RPE) cells the only MMP detected was MMP-2. RPE cells in culture did not respond to either treatment with a change in their MMP secretion.

CONCLUSION

We detected a profound upregulation of both MMP-3 and MMP-9 and a mild induction of MMP-2 through latanoprost in the ciliary body, but not the trabecular meshwork or RPE cells. Corticosteroids, on the other hand, downregulated MMP expression in both tissues. This inhibiting effect of corticosteroids on MMP production was reversed by latanoprost.

Long-term follow-up of cytokines and soluble cytokine receptors in peripheral blood of patients with juvenile rheumatoid arthritis

Plasma levels of interleukin-1beta (IL-1beta), IL-2, soluble IL-2 receptor (sIL-2R), IL-6, IL-8, tumor necrosis factor-alpha (TNF-alpha), and the p60 soluble TNF receptor (sTNFR) were repeatedly determined by enzyme-linked immunosorbent assays (ELISA) in 35 patients with different subtypes of juvenile rheumatoid arthritis (JRA) during an observation period of up to 36 months. The data were related to conventional inflammatory parameters and disease activity. Patients with systemic disease showed the most pronounced elevations of plasma cytokines, followed by polyarticular and pauciarticular JRA. Soluble receptors sIL-2R and sTNFR were consistently elevated in patients of all JRA subtypes and indicated disease activity even in patients with normal C-reactive protein (CRP). In contrast, the determination of IL-1beta, IL-2, IL-8, and TNF-alpha revealed strikingly different individual profiles in patients of the same clinical subtype of JRA and irrespective of disease activity. It is concluded that the determination of sIL-2R and sTNFR may be relevant for monitoring JRA, as they indicate disease activity also in cases with unaltered conventional inflammatory parameters. The different individual cytokine profiles of patients within identical subtypes of disease suggest JRA to be even more heterogeneous than hitherto assumed. The data should be considered in attempts to develop anticytokine strategies in the therapy of JRA.

Early rheumatoid arthritis is associated with diminished numbers of TH1 cells in stimulated peripheral blood

Rheumatoid arthritis (RA) has been associated with an altered TH1/TH2 balance. Here we present first results with a technique to quantitate stimulated TH1 and TH2 subsets in whole blood by means of cytofluorimetric detection of intracytoplasmic TH1 and TH2 cytokines. A group of 10 patients suffering from initial stages of RA exhibited a significantly reduced percentage of TH1 cells (11.0 +/- 2.0%) in the peripheral blood as compared to 13 healthy, age matched controls (28.8 +/- 2.0%). The TH2 response, as determined by intracellular expression of IL-4, remained unchanged. The data may indicate a defect in the TH0-TH1 differentiation or/and a selective trapping of TH1 cells into the affected joints.

Activation of the haemostatic system in children with juvenile rheumatoid arthritis correlates with disease activity

Twenty-four children with juvenile rheumatoid arthritis (JRA) and 10 children with postinfectious arthropathies were investigated for markers of blood coagulation and fibrinolytic activity: Prothrombin fragment 1+2 (F1+2), thrombin-antithrombin complex (TAT), and D-Dimer were measured using solid phase enzyme linked immunosorbent assays (ELISA). Results were compared with clinical and conventional laboratory signs of disease activity. F1+2, TAT, D-Dimer, and fibrinogen were significantly elevated in children with JRA as compared with healthy children and children with postinfectious arthropathies. F1+2, TAT, and D-Dimer correlated significantly with disease activity, assessed by determination of the joint index score and C-reactive protein (CRP). The study demonstrates a subclinical activation of the haemostatic system in children with JRA correlating with disease activity, which might be caused by the action of several immunomediators on cells (monocytes, endothelial cells) playing a role in the regulation of blood coagulation activity.

Circadian rhythm of the soluble p75 tumor necrosis factor (sTNF-R75) receptor in humans--a possible explanation for the circadian kinetics of TNR-alpha effects

Circadian alterations of several immune functions in vivo are well established, and may have important physiological and clinical implications. In line with this, tumor necrosis factor (TNF)-alpha has been implicated in the circadian regulation of body temperature. As soluble TNF receptors (TNF-R) act as naturally occurring competitive inhibitors of this cytokine, we investigated plasma levels of the soluble sTNF-R55 and sTNF-R75 in comparison with plasma cortisol and body temperature in nine healthy male volunteers during a defined 16 h light/8 h dark cycle. It was found that sTNF-R75, but not sTNF-R55, exhibited a clear-cut circadian rhythm with a significant (P < 0.01) peak at 7:51 a.m. +/- 58 min. The phase of the sTNF-R75 rhythm preceded that of cortisol by approximately 1 h and inversely corresponded to the circadian rhythm of body temperature. Moreover, the individual amplitudes of sTNF-R75 and body temperature exhibited a significant (P < 0.01) positive correlation. These results suggest that (i) the two sTNF-R are regulated independently, (ii) the sTNF-R75 rhythm is not primarily due to the cortisol rhythm and (iii) the fluctuation of the sTNF-R may contribute to the regulation of body temperature by modulating the availability of free TNF.

Cytokines in juvenile rheumatoid arthritis (JRA)

Juvenile rheumatoid arthritis (JRA), unlike rheumatoid arthritis of adulthood (RA), is a heterogenous disease comprising at least five subtypes that differ in clinical course and prognosis, and require different therapeutical approaches. As compared to RA, the production of local and systemic cytokines in JRA have not yet been as extensively investigated. In this article we review the available literature on cytokine expression in serum and synovial fluid in all five different subtypes of JRA. Even though the data are still fragmentary, the evidence so far suggests that the determination of serum cytokines yields relevant information as to clinical subtype and inflammatory activity of the disease. Furthermore, the cytokine data suggest that the pathogenesis of JRA may even by more heterogenous than defined by the clinical subtypes. Finally, future directions of research in this area are proposed, and-based on the latest results-arguments for (anti)cytokine therapies in JRA are critically discussed.

Serum cytokines in juvenile rheumatoid arthritis. Correlation with conventional inflammation parameters and clinical subtypes

OBJECTIVE

To examine the usefulness of determining extended serum cytokine profiles in patients with juvenile rheumatoid arthritis (JRA), for the purpose of improving differential diagnosis and monitoring disease activity.

METHODS

In a 2-year prospective study, serum levels of interleukin-1 beta (IL-1 beta), soluble IL-2 receptor (sIL-2R), IL-6, IL-8, tumor necrosis factor alpha (TNF alpha), and the p55 soluble TNF receptor (sTNFR) were repeatedly determined by enzyme-linked immunosorbent assay in 40 patients with JRA, 13 patients with postinfectious arthropathies, and 30 healthy controls. The data were compared with conventional parameters of inflammation, such as C-reactive protein (CRP), iron and hemoglobin levels, erythrocyte sedimentation rate (ESR), white blood cell (WBC) counts, and platelet counts. WBC subsets were analyzed by flow cytofluorometry.

RESULTS

At the first visit and at the peak of inflammatory activity according to CRP levels and/or ESR, serum levels of sIL-2R, IL-6, and sTNFR in JRA patients correlated significantly with conventional inflammation indicators, whereas IL-1 beta, IL-8, and TNF alpha did not. No changes in leukocyte subset distribution were noted. Among the different clinical subtypes of JRA, sIL-2R, IL-6, and sTNFR values at the time of the initial visit showed a pattern similar to CRP, whereby patients with systemic disease exhibited by far the highest values. TNF alpha and IL-1 beta were variably elevated in certain JRA subtypes. Patients with postinfectious arthropathies showed elevated levels of CRP, sIL-2R, TNF alpha, and sTNFR, which did not differ significantly from levels in the various JRA subtypes with the exception of systemic disease. Detailed analysis of types I and II pauciarticular JRA revealed that levels of CRP, IL-1 beta, and TNF alpha were elevated in patients with type I disease. While these parameters were invariably normal in patients with type II disease, sTNFR and sIL-2R were still found to be significantly elevated. Followup studies suggested that persistently high sTNFR values are a better indicator of JRA activity than are measurements of other cytokines or CRP.

CONCLUSION

JRA is associated with significant and consistent changes in serum levels of inflammatory cytokines and soluble receptors. For the clinical monitoring of JRA, determination of levels of sTNFR, and to some extent sIL-2R, may be particularly useful, since these determinations yield information about subtype and/or activity of disease that is not available from conventional parameters of inflammation.

Enhancing in vivo effect of propranolol on human lymphocyte function is not due to stereospecific beta-adrenergic blockade

Immunoenhancing in vivo effects of beta-adrenergic blockers have been previously ascribed to a reduced beta-receptor-mediated immunosuppression. In the present study using a whole blood stimulation assay, the effects of a five-day treatment with the purified (R)- or (S)-isomer of propranolol (3 x 40 mg/day) on the polyclonal in vitro responsiveness of peripheral blood lymphocytes (PBL) of normothyroid and hyperthyroid persons were assessed. It is shown that both isomers likewise exhibit a significant enhancing effect on the proliferative response of PBL to T and B cell mitogens, which strongly argues for nonspecific effects of propranolol to be responsible rather than a specific beta-adrenergic receptor blockade.

Late-onset miliary pneumonitis after near drowning

We report a 7-year-old pediatric patient with an apparently self-limiting, subacute miliary pneumonitis that occurred 6 weeks after a near-drowning accident in shallow, muddy water. After biopsy, histological examination revealed aspirated foreign bodies (algae and pollen grains) in the affected lung areas and a foreign body reaction in the form of a granulomatous inflammation. The lack of any detectable infectious agents suggested a causative role of these aspirated algae and pollen grains in the development of lung disease.

Opposite effects of mild and severe stress on in vitro activation of rat peripheral blood lymphocytes

The effects of short-term handling and different durations of immobilization on serum levels of catecholamines, ACTH, prolactin, and corticosterone and in vitro functions of lymphocytes were examined in rats. The results show that changes in the immune response of peripheral blood lymphocytes (PBL) depend on the intensity of the stressor: Short (1 min) handling of cannulated rats induced an enhanced stimulation of PBL to respond to T and B cell mitogens, whereas immobilization of the same animals led to suppression, dependent on the time this stressor was applied. The decrease in the mitogen reactivity of PBL after 120 min of immobilization was reversible within 24 h, and could be largely prevented by adrenalectomy, confirming that factors released by this gland are mainly responsible for immunosuppression. In contrast to PBL, spleen cells showed an enhanced mitogen response to immobilization and adrenalectomy, indicating that the immune response is differently regulated in the various compartments of the immune system. Possible correlations of the various effects with changes in stress hormone levels are discussed.

Continuous in vivo treatment with catecholamines suppresses in vitro reactivity of rat peripheral blood T-lymphocytes via α-mediated mechanisms

A 20 h continuous treatment of rats with catecholamines, using subcutaneously implantable retard tablets, had either no (adrenaline, isoproterenol, midodrine) or a slight (noradrenaline) suppressive effect on the in vitro responsiveness of peripheral blood T-lymphocytes. A marked suppression of the mitogen response ensued when adrenaline, noradrenaline or midodrine, but not isoproterenol, was applied together with the beta-receptor blocker propranolol, whereas the combination with the alpha-receptor blocker phentolamine had no effect. The mitogen response of splenic lymphocytes was not affected by any of these treatments. This alpha-mediated adrenergic suppression of peripheral blood T-cells was not correlated with general metabolic alterations, shifts in white blood cell counts or CD4+/CD8+ subsets, or with elevated glucocorticoid levels. The data suggest that to consistently influence the reactivity of rat peripheral blood lymphocytes by chronic adrenergic stimuli in vivo requires both high catecholamine levels and a bias towards alpha-adrenergic receptivity.

Cytofluorimetric analysis of mitogen-activated peripheral blood lymphocytes of non-leukemic lymphoma patients reveals an abnormal disease-related expression pattern of activation antigens

The purpose of this study was to examine patterns of peripheral T-cell-activation antigen expression after polyclonal in vitro stimulation in early stages of lymphoproliferative diseases. With 18 patients afflicted with recently diagnosed, non-leukemic stages of B and T cell lymphoma cytofluorimetric analysis was performed with peripheral blood lymphocytes (PBL) after 72 h in culture with and without phytohemagglutinin, using antibodies against the differentiation antigens CD3, CD8, CD4, CD16, CD19, CDw14, and the activation antigens interleukin-2 receptor (IL-2R, CD25), HLA-DR (DR), CD56 and transferrin receptor (TR). Compared to healthy controls and patients with other diseases, a very significant reduction of large T cells bearing activation markers was found in all lymphoma cases. Furthermore, a pronounced inhibition in the expression of the activation markers IL-2R and TR, but not of DR, was detected on CD3+ cells in phytohemagglutinin-stimulated PBL of all lymphoma cells independently of DNA synthesis, as measured by [3H]thymidine uptake. Determination of the natural-killer-cell-(NK)-associated antigens CD16 and CD56, available for our studies in a CD16 + CD56 combination kit, revealed, after phytohemagglutinin stimulation, significantly increased expression values in 8 lymphoma patients so far investigated, as compared to 12 healthy controls. Thus, polyclonal activation combined with cytofluorimetric screening of activation antigens seems to give useful information on the functional defect(s) of PBL in an early state of lymphoma, and may therefore be of considerable diagnostic value. The observed pattern of T cell activation antigen expression after phytohemagglutinin stimulation may give further clues to the understanding of immune dysfunction(s) associated with lymphoma.

Peripheral blood lymphocytes of nonleukemic lymphoma patients exhibit aberrant expression of T-cell activation markers after polyclonal stimulation in vitro

The authors evaluated suppressed in vitro functions of peripheral blood lymphocytes (PBL) as a possible tool in the early diagnosis of human lymphoma. In 13 of 22 patients with recent onset of various types of nonleukemic lymphomas (Mb. Hodgkin and non-Hodgkin's lymphomas of B-cell and T-cell origin) the mitogen response of PBL against phytohemagglutinin (PHA) and concanavalin A (Con A), as measured by 3H-thymidine (3HTdR) uptake, was found to be significantly suppressed, whereas the response to pokeweed mitogen (PWM) was normal in 18 cases. In parallel, cytofluorimetric analysis was done with PBL after 72 hours in culture with and without PHA, using antibodies against the differentiation antigens: CD3, CD8, CD4, CD19, and CDw14 and the activation antigens: interleukin-2 (IL-2) receptor (IL-2R, CD25), human leukocyte antigen DR (HLA-DR), and transferrin receptor (TR). Compared with healthy controls and patients with other diseases, a significant reduction of the total T-cell blast response, i.e., the percentage of large T-cells bearing activation markers, was found in all lymphoma cases including those with a normal 3HTdR uptake. Furthermore, a pronounced inhibition in the expression of the activation markers Il-2R and TR, but not of HLA-DR, was detected on CD3+ cells in PHA-stimulated PBL of all lymphoma cases. Thus, polyclonal activation combined with activation antigens seems to give more accurate information about the functional defect(s) of PBL in an early state of lymphoma; these parameters may therefore be valuable diagnostically. The abnormal pattern in the expression of T-cell activation antigens after polyclonal stimulation may help in the understanding the cellular immune defects associated with lymphoma.

[Suppression of lymphocyte function 2 years following surgical treatment of paranasal sinus mycosis]

Prior investigations showed that acutely diseased patients with an aspergillus sinusitis manifested immune dysfunctions in respect of both T and B lymphocytes. In contrast to patients with nonmycotic sinusitis reduced in vitro and in vivo responsiveness was observed. The aim of this study, carried out after removal of the fungus ball and endoscopic surgery in clinically healthy patients, was to ascertain whether this reduced responsiveness was to be regarded as the effect or cause of an Aspergillus fumigatus infection. Two years later, the in vivo response to recall antigens was normal in both groups of patients, whereas the response to mitogens (ConA, PHA and PWM) was still decreased in the aspergillus sinusitis groups. The data suggest that the reduced immune response is a consequence of the Aspergillus fumigatus infection. Depressed skin reactivity is only present during acute infection, while proliferative capacity, as measured in the "whole blood stimulation" assay is depressed for a long time after healing the acute infection.