Importancia del sinovianálisis en reumatología / Importance of synovial fluid examination in rheumatology

El examen del líquido articular debe ser parte obligada de la investigación del derrame articular. Se describe la metodología de estudio del líquido sinovial que realizan los autores. Analizan los elementos normales, las alteraciones físicas y químicas, los cambios en la celularidad y la aparición de cristales correlacionando los cambios con las probables patologías que las determinan. Se desglosa en tres secciones de acuerdo a la forma de conservar la muestra, facilitando la comprensión de los procedimentos de estudio a los que se somete el líquido sinovial

[Spectrophotometric study of synovial exudate in differential diagnosis of pigmented villonodular synovitis]. / Spektrofotometricheskoe issledovanie sinovial'nogo vypota v diagnostike pigmentnogo vorsinchato-uzelkovogo sinovita.

The authors have studied the spectrophotometric characteristics of the synovial exudates in the patients with diseases of the knee joint of various etiology. The presence of two main maximums of the absorption spectra has been revealed in the wave frequencies of 280 and 460-465 nm. It has been determined that with regard to the optical densitys in the protein component (280 nm) and the pigments (460 nm) absorption area it is possible to differentiate very precisely pigmented villondular synovitis and other pathologies.

A rapid and highly sensitive method for the quantitative determination of dexamethasone in plasma, synovial fluid and tissues by combined gas chromatography/negative ion chemical ionization mass spectrometry.

A new, simple and highly sensitive assay is developed for the quantitative measurement of very low levels of dexamethasone in human plasma, synovial fluid and tissues following a topical administration of the drug. Dexamethasone and the internal standard, flumethasone, are measured by gas chromatography/negative ion chemical ionization mass spectrometry with methane as the reagent gas. After a three-step extraction procedure, the two compounds of interest are converted to their trimethylsilyl ether derivatives using trimethylsilylimidazole and formamide as the base catalyst. Under soft derivatization conditions only one chromatographic peak corresponding to the trisubstituted derivative is observed. The mass spectrometer is focused to monitor abundant and stable characteristic high-mass ions (m/z 446 and 464) which are generated in the ion source by an electron capture process. This assay requires only 1 ml of plasma or 0.5 ml of synovial fluid and the detection limit of the method is equal to 0.1 ng ml-1 with a relative standard deviation lower than 6%.

Determination of cathepsins B and H in sera and synovial fluids of patients with different joint diseases.

Synovial fluids and sera of patients with inflammatory and metabolic joint diseases contain different cysteine proteinases. The quantities of cathepsins B and H were determined by newly developed specific enzyme-linked immunoassay tests (ELISA), with detection limits of 0.5 microgram/l for cathepsin B and 3 micrograms/l for cathepsin H. The values of cathepsin B in normal sera ranged from 0.6 microgram/l to 2 micrograms/l, whereas in sera of patients with joint diseases they ranged from 1.7 micrograms/l to 18 micrograms/l. Cathepsin H was not found in sera (values below 3 micrograms/l), but was measurable in patients' synovial fluids. Patients with rheumatoid arthritis have on average the highest values of cathepsin B in synovial fluids, whereas patients with undifferentiated arthritis have the highest values of cathepsin H. The results show that cathepsins B and H are present in arthritic synovial fluids, where they may be implicated in destructive processes. There is yet no clear correlation between the quantity of each cathepsin released in synovia and the clinical diagnosis or the stage of the disease.

Tumor necrosis factor alpha and interleukin 1 beta in synovial fluid of infants and children with suppurative arthritis.

Tumor necrosis factor alpha and interleukin 1 beta concentrations were measured in synovial fluid of 24 infants and children with diagnoses of suppurative arthritis (n = 16) and other kinds of arthritis (n = 8). Large concentrations of tumor necrosis factor alpha (range, 100 to 85,000 pg/mL) were found in 12 (75%) of 16 patients with bacterial infection and in none of the patients with noninfectious origins. Large concentrations of interleukin 1 beta (greater than 200 pg/mL) were found in 15 (94%) of 16 patients with bacterial infection and in none of the other patients. In the latter group, small concentrations of interleukin 1 (range, 40 to 120 pg/mL) were present in 5 (63%) of 8 patients. Serum samples obtained simultaneously were negative for both cytokines. Tumor necrosis factor alpha and interleukin 1 beta concentrations correlated significantly and with leukocyte counts in synovial fluid. We conclude that large concentrations of tumor necrosis factor alpha and interleukin 1 beta are produced locally in patients with suppurative arthritis and they may be potentially useful in differentiating this condition from other kinds of arthritis.

Peripheral arthrocentesis in the work-up of acute low back pain.

Involvement of the axial skeleton in acute gouty arthritis has rarely been reported. Without the presence of peripheral tophi or history of gout, this diagnosis is often not considered. A patient is described with acute low back pain and for whom a diagnosis of acute axial gout was suggested after arthrocentesis of an asymptomatic peripheral joint yielded monosodium urate crystals. Treatment with colchicine led to prompt resolution of the gouty flare. Demonstration of urate crystals in this manner may encourage the clinician to attempt a trial therapy for acute gout, or at least to add gout to the differential diagnosis of acute back pain.

Partial purification and characterisation of a synovial fluid inhibitor of osteoblasts.

A polypeptide inhibitor of osteoblast proliferation is described which occurs in synovial effusions of patients with rheumatoid arthritis. Partial purification of the inhibitor showed a molecular weight of approximately 81,000 by gel electrophoresis. This polypeptide seems to be unique as no inhibitor of osteoblasts of similar molecular weight has been previously described in rheumatoid synovial effusions.

[A fluorescence spectrometric study of synovial exudate in the diagnosis of chronic joint diseases]. / Spektral'no-fliuorestsentnoe issledovanie sinoval'nogo vypota v diagnostike khronicheskikh zabolevanii sustavov.

The spectro-fluorescent characteristics of synovial exudate in different diseases of the knee joint were studied. It was established that in pigmented villonodular synovitis the position of the maximum of fluorescence spectrum of synovial exudate was in the range of 510-530 nm and in synovitis of other etiology 430-440 nm. The authors propose a method of differential diagnosis of pigmented villonodular synovitis by fluorescent parameters of synovial exudate.

The catalytic activity of iron in synovial fluid as monitored by the ascorbate free radical.

Human synovial fluid, from a patient with synovitis disease, was examined by electron spin resonance spectroscopy for evidence of free radicals. The ascorbate free radical was observed and its intensity was affected by iron chelating agents, demonstrating that the iron in the synovial fluid is indeed available for oxidative catalysis.

[Joint tolerance of pefloxacin and ofloxacin in children and adolescents with cystic fibrosis]. / Tolérance articulaire de la péfloxacine et de l'ofloxacine chez les enfants et adolescents atteints de mucoviscidose.

Retrospective analysis of 63 patients with mucoviscidosis (age: 11 to 21 years), treated with pefloxacine, shows the occurrence of arthropathies ascribed to pefloxacine in 9 patients (age: 9 to 20 years), or 14% of the patients under treatment. The dose of pefloxacine was normal (9 to 16 mg/kg/day) in all cases, except one case of overdose (29 mg/kg/day). Mechanical arthralgias, affect the knees, elbows and wrists, resulting in functional discomfort, and frequently accompanied by mechanical synovial extravasation. They always subside after pefloxacine is discontinued. The role of age is essential as the incidence of arthropathies reaches 45% when pefloxacine is first administered between the ages of 15 and 20 years. Retrospective analysis of 37 patients with mucoviscidosis (age: 2 to 20 years), treated with ofloxacine, failed to show any joint complication. In this study, the best joint tolerance of ofloxacine, compared with pefloxacine is statistically significant. Arthropathies induced by pefloxacine represent an original entity which seems related to the cartilage toxicity of quinolones, observed in animal experiments, during growth.

IL-6/IFN-beta 2 in synovial effusions of patients with rheumatoid arthritis and other arthritides. Identification of several isoforms and studies of cellular sources.

We have looked for IL-6, a cytokine that has immunomodulating and inflammation-associated activities, in joint exudates (fluid and mononuclear cells) from patients with rheumatoid arthritis and other arthritides using both biologic and biochemical assays. IL-6 was assessed by its ability to stimulate alpha 1-antichymotrypsin secretion from the human hepatoma cell line Hep3B clone 2, an activity which is blocked by an antiserum to Escherichia coli derived IL-6, and by the growth of the IL-6-dependent murine hybridoma 7TD1 cell line. IL-6 isoforms in synovial fluid were characterized by immunoaffinity chromatography followed by Western blotting. The presence of IL-1 in synovial fluids and its production by synovial fluid mononuclear cells was monitored by Western blotting and indirect immunofluorescence with polyclonal anti-IL-1 beta antisera. In an analysis of 30 effusions from 27 rheumatoid patients with acutely inflamed joints, abundant quantities of IL-6 (greater than 2 ng/ml) were detected in 23 by the alpha 1-antichymotrypsin bioassay. Several rheumatoid synovial fluids also had elevated IL-6 levels in the 7TD1 bioassay. Seven of nine nonrheumatoid effusions also contained high levels of IL-6 (greater than 2 ng/ml). No IL-1 (less than 0.25 ng/ml) could be detected by Western blotting in 10 rheumatoid effusions even though eight of these contained high levels of IL-6. The IL-6 activity could be neutralized with a rabbit antiserum to rIL-6. Multiple IL-6 isoforms (25, 30, 45 kDa) were present in two rheumatoid and one traumatic effusion studied. Fresh mononuclear cells isolated from various synovial effusions did not appear to make IL-6 constitutively, as no IL-6 could be detected in the media of cells cultured for 12 to 18 h after isolation. Similarly, there was no constitutive production of IL-1 by these cells. However, synovial fluid mononuclear cells could be induced to secrete both IL-6 and IL-1 after stimulation with LPS. The LPS-responsive cells were monocytes and not lymphocytes or dendritic cells. These findings suggest that IL-6 is involved in inflammatory joint disease. However, the primary cells synthesizing it may be located in the synovial lining instead of the joint exudate.

Synovial fluid glycosaminoglycan (acid mucopolysaccharide) analysis in assessment of temporomandibular joint dysfunction. A pilot study.

Temporomandibular joint (TMJ) synovial fluid was aspirated from normal control subjects and patients undergoing surgery for TMJ dysfunction. The glycosaminoglycan (GAG) composition of this fluid was analysed and compared with the clinical diagnosis and histological appearance of the condylar tissues. Changes in GAG composition were observed where a histologically hyperplastic response was seen in joint tissues, but these findings did not necessarily correlate with the initial clinical diagnosis. It is suggested that the fluid composition reflects the current metabolic activities of the tissues and may provide a useful marker of such processes.

Arthropathy associated with Brucella abortus strain 19 vaccination in cattle. I. Examination of field cases.

Thirty cows presenting with lameness and persistent serological reactions to Brucella abortus had chronic granulomatous arthropathy of the femorotibial and occasionally other joints. Attempts to culture Brucella or other pathogens gave negative results but organisms of Brucella morphology were seen in fluorescent antibody-stained cryostat sections of synovial tissue. The synovial fluids contained high titres of antibodies to B. abortus and Yersinia enterocolitica O:9 and had elevated total protein and immunoglobulin concentrations showing an oligoclonal electrophoretic profile. Immune complexes and rheumatoid factor were detected in some of the fluids.

Magnetic resonance imaging of the ischemic hip. Alterations within the osteonecrotic, viable, and reactive zones.

To explore the ability of magnetic resonance imaging (MRI) to depict the morphologic features of avascular necrosis (AVN) of the femoral head and to determine whether a classification based on stage of necrosis is possible, images of hips with 56 proved lesions were examined and correlated with roentgenographic stage, severity of pain and functional impairment, and available computed tomography (CT) scans. Six femoral heads with AVN were also studied ex vivo with MRI, CT, roentgenographic, and histologic examinations. These examinations were compared with 100 normal hips in 50 individuals and one normal proximal femoral specimen. The reactive interface between live and dead bone at the periphery of AVN lesions had a characteristic MRI appearance that facilitated diagnosis. Based on central signal intensity on two different pulse sequences, lesions could be separated into four classes that correlated with roentgenographic and clinical staging. Lesions that were isointense with fat on both sequences had an earlier roentgenographic stage and less severe symptoms than did lesions that were less intense than fat. Among hips with AVN in patients younger than 50 years of age, 67% had premature conversion to fatty intertrochanteric marrow outside the borders of the lesion. Detecting premature conversion to fatty marrow has important implications regarding the pathogenesis of AVN and may aid early diagnosis. MRI provides pathophysiologic information that is different from information obtained from conventional methods or various combinations of methods and may provide a basis for an improved system for grading AVN lesions.

Diagnóstico de gota no período intercrítico pela funçäo articular e achado de cristais / Gout diagnosis in the intercritic period by joint puncturing and finding of crystals

O encontro de cristais de monourato de sódio em líquido sinovial é um critério diagnóstico maior e absoluto na gota, mas só recentemente tem-se usado esta propedêutica no período intercrítico. Os autores estudaram 14 pacientes, todos do sexo masculino, com idade variando entre 28-69 anos, assintomáticos, com diagnóstico prévio de gota näo tofácea, em período intercrítico; evidenciaram cristal de monourato de sódio em líquido sinovial do joelho de nove (64,2%) pacientes e em 13(59%) líquidos sinoviais dos 22 joelhos puncionados. Em nove pacientes, nos quais a punçäo foi bilateral, a positividade foi de 77,7%. Esses resultados säo concordantes com estudos anteriormente publicados na literatura internacional e valorizam a punçäo articular, para pesquisa de cristais de monourato de sódio, como método sensível no diagnóstico de gota näo tofácea, no período intercrítico

Cytokines in chronic inflammatory arthritis. II. Granulocyte-macrophage colony-stimulating factor in rheumatoid synovial effusions.

A liquid culture technique was used to study 23 synovial fluids (SF) (21 from inflammatory joint diseases and 2 noninflammatory SF) and supernatants of two cultured rheumatoid arthritis (RA) synovial tissues for colony-stimulating factor (CSF). The proliferative responses of human peripheral blood macrophage-depleted non-T cells treated with synovial fluids, supernatants of synovial tissue explants, and recombinant granulocyte-macrophage (rGM)-CSF were compared. Aggregates of cells that formed in long-term cultures (15 d) were similar for each applied agent and consisted of macrophages, eosinophils, and large blasts. Tritiated thymidine incorporation was proportional to the concentration of rGM-CSF and was accompanied by an increase in number and size of cellular aggregates formed in the cultures. CSF activity was observed in inflammatory SF, with tritiated thymidine uptake of 3,501 +/- 1,140 cpm in the presence of RA samples (n = 15) compared to 1,985 +/- 628 for non-RA inflammatory SF (n = 7) (P less than 0.05) and 583 +/- 525 for medium (n = 6) (P less than 0.01). The proliferative response to RA SF was often more apparent when the samples were diluted, because at higher concentrations the RA SF was inhibitory. Two RA SF were fractionated by Sephadex G100 column chromatography; low levels of CSF activity were detected in fractions corresponding to Mr of 70-100 kD, but the major CSF activity was found in the 20-24-kD fractions. A polyclonal rabbit anti-GM-CSF antibody eliminated the stimulating activity from both rGM-CSF and RA SF. Finally, a specific RIA identified significant levels of GM-CSF (40-140 U/ml) in the culture supernatants of 3 additional RA synovial tissues. These data document the local production of GM-CSF in rheumatoid synovitis and are the first description of this cytokine at a site of disease activity.

Interleukin-6 in synovial fluid from patients with arthritis.

Synovial fluid and serum from patients with rheumatoid arthritis, other inflammatory arthritides, and traumatic arthritis were assayed for the presence of interleukin-6 (IL-6) by means of an IL-6-dependent mouse hybridoma cell line. The cytokine was detected in all the samples of synovial fluid (range 50-22000 U/ml). IL-6 in synovial fluid was positively correlated (r = 0.58, P = 0.03) with the erythrocyte sedimentation rate in patients with inflammatory arthritis. In serum, the concentration of IL-6 was slightly elevated in some patients with rheumatoid arthritis. The results demonstrate that IL-6 is released into synovial fluid in joints affected by arthritis, and there appears to be an association between the levels of IL-6 and disease activity.