Disease course in systemic lupus erythematosus: changes in health status, disease activity, and organ damage after 2 years

OBJECTIVE

To examine changes in health status, disease activity, and organ damage after 2 years and to study possible disease variables predicting change in health status, disease activity, and organ damage at followup in systemic lupus erythematosus (SLE). Second, to compare changes in health status in patients with SLE to that of matched patients with rheumatoid arthritis (RA) and matched healthy controls.

METHODS

A 2 year longitudinal observational study, measuring health status (Short-Form 36. visual analog scale for pain and fatigue, modified Health Assessment Questionnaire, patient global assessment of disease activity), disease activity, and organ damage in 87 patients with SLE. Health status measures in SLE were compared to 65 matched RA patients selected from the Oslo RA register and to 77 matched healthy controls from the population register.

RESULTS

On a group level the SLE patients showed stable health status measures and disease activity scores 2 years after baseline, but organ damage scores increased significantly. Increase in organ damage was significantly and independently predicted by baseline scores of disease activity and organ damage, health status, and disease activity by the respective baseline scores. Changes in health status measures over 2 years were similar in SLE, RA, and healthy controls.

CONCLUSION

Our 2 year longitudinal observational SLE study showed a stable course of health status and disease activity, whereas organ damage increased. Disease activity and organ damage at baseline predicted the latter. Our results indicate the value of careful monitoring of disease activity over time in SLE and individually tailored treatment guided by the predictors of course and outcome.

Characterization of proteoglycans and glycosaminoglycans in splenic AA amyloid induced in mink

Amyloidosis of the protein AA type is readily induced in mink using repeated injections of bacterial lipopolysaccharide (LPS). We have characterized splenic proteoglycans/glycosaminoglycans (PGs/GAGs) in mink during amyloidogenesis. Moderate to rich amounts of amyloid exhibiting green birefringence was demonstrated by polarization microscopy of the splenic section stained with Congo red in seven out of eight minks after 10 weeks of LPS-treatment, and a significant increase in the total amount of PGs and GAGs in AA amyloid spleens was observed (two to eight times that in unstimulated animals). Intact PGs as well as free GAGs were extracted, and heparan sulfate (HS) was the most abundant GAG in the amyloid as well as in the control spleens. The GAGs showing the most pronounced increase in the amyloid spleens was of the chondroitin sulfate/dermatan sulfate (CS/DS) type and these were extracted in the form of free GAG chains. We conclude that there is a selective enrichment of PGs/GAGs in extracted splenic amyloid in the mink, which confirms to previous observations in human amyloid as well as in other animal species, supporting their pathogenic significance in the formation of AA amyloid.

Glycosylation of immunoglobulin light chains associated with amyloidosis

AL amyloidosis is a fatal disease caused by deposition of immunoglobulin light chains in a fibrillarforin (AL) in various organs. By searching the Kabat database of immunoglobulin sequences using the KabatMan software, we have shown that there is a preponderance of the consensus glycosylation sequon (AsnXxxSer/Thr) in the framework regions of amyloid light chains. We have characterised by computer graphics simulations, NMR spectroscopy and carbohydrate biochemistry the structure and conformation of the oligosaccharide from amyloid protein AL MS (lamba1) and from the amyloid associated Bence Jones protein of patient MH (kappa1). These proteins have glycosylation in the hypervariable complementarity-determining region versus framework region, respectively. Both contained a 2-6 sialylated core fucosylated biantennary chain mostly with bisecting GIcNAc. Together our results suggest that light chain glycosylation may be one of several modifications which may render the protein more prone to amyloid formation.

The amino acid sequence of a monoclonal gamma 3-heavy chain from a patient with articular gamma-heavy chain deposition disease

Abnormal deposition of proteins, including monoclonal immunoglobulin gamma-heavy chains, may cause tissue damage and organ dysfunction. We here report the amino acid sequence of the free gamma-heavy chains present in serum and urine of the first reported case (patient G. L.) of synovial heavy chain deposition disease. The protein was heavily deleted and consisted of the hinge, in addition to the CH2 and CH3 domains, in a dimeric form, thus lacking its variable domain as well as the CH1 domain. The sequence was consistent with the gamma 3 subclass (gamma 3GL). Gm typing revealed the gamma 3 allotypes G3m(b0) and G3m(b1) in accordance with the residues Pro123, Phe128, Thr171 and Phe268 in gamma 3GL. Furthermore, the gamma 3GL molecule was glycosylated at Asn in position 129. Finally, the gamma 3GL protein was shown to contain a typical binding site for the first complement component, C1q, namely the residues Glu150, Lys152 and Lys154, with the potential of binding and activating complement, causing tissue damage following deposition.

Bone mineral density in systemic lupus erythematosus: comparison with rheumatoid arthritis and healthy controls

OBJECTIVES

To examine bone mineral density (BMD) frequency of osteoporosis and reduced bone mass in systemic lupus erythematosus (SLE), and compare the data of the SLE patients with matched rheumatoid arthritis (RA) patients and healthy controls. Secondly, to study possible correlations between BMD, demographic and disease variables in the SLE patients.

METHODS

Measures of BMD assessed by dual energy x ray absorptiometry were obtained from 75 SLE patients aged </= 70 years, 75 RA patients matched for age, sex and disease duration, and from 75 healthy controls matched for age, sex and geographical area. Disease activity and accumulated organ damage were assessed in the SLE patients.

RESULTS

The SLE patients had significantly lower BMD values at lumbar spine L2-L4 and hip, and higher frequency of osteoporosis at all sites of measurement compared with matched healthy controls. The matched SLE and RA patients had similar BMD, prevalence of osteoporosis and reduced bone mass. In the SLE patients BMD was more strongly correlated with accumulated organ damage than with markers of disease activity or duration. In multivariate analyses BMD was at all sites predicted by age and body mass, at lumbar spine also by the current corticosteroid dose.

CONCLUSION

The study showed reduced BMD in patients with SLE compared with matched healthy controls. Premenopausal women taking corticosteroids were especially affected. Furthermore, the BMD of matched SLE and RA patients was reduced to a similar extent.

Is there a pathogenic link between gamma heavy chain disease and chronic arthritis?

In 1991, gamma heavy chain disease was diagnosed in a 43-year-old female, who 3 years earlier had contracted an erosive seronegative chronic arthropathy. In 1996, her lymphoproliferative disorder required treatment with melphalan and prednisolone. Laboratory studies revealed a gamma3 heavy chain monoclonal component in serum and urine. Massive localization of plasma cells and blasts with cytoplasmic or cell membrane staining for gamma3 chains, but no staining for light chains, was observed by immunohistochemical studies of bone marrow as well as affected synovial tissue. Large amounts of extracellular gamma3-chains were also deposited in the synovial membrane. This is the first documentation of gamma heavy chain deposition disease directly affecting articular structures. Whether it represents the primary pathogenic event followed by reactive inflammatory changes in the joints, or another example of gamma heavy chain disease preceded by chronic arthritis, remains elusive. Regardless, several common cellular and molecular mechanisms discussed here suggest a pathogenic link between the two disease processes.

Prognostic factors for the development of fibromyalgia in women with self-reported musculoskeletal pain. A prospective study

OBJECTIVE

To estimate the risk of developing fibromyalgia (FM) in women with self-reported pain and to estimate the relative risk of a series of variables.

METHODS

As part of a population study, 214 women with self-reported pain were interviewed and examined in 1990 and 1995. In 1990, 39 of these women fulfilled the American College of Rheumatology criteria for FM. The other 175 women represented a continuum of pain extent from nonchronic pain to chronic widespread pain, and were assessed as individuals at risk for developing FM. Potential risk factors for FM were registered in 1990 and analyzed by bivariate and multiple statistical methods in the total sample and also in a subgroup of 115 women with limited pain.

RESULTS

Forty-three (25%) women developed FM. Having > or = 4 associated symptoms, pain of > or = 6 years' duration, back pain, alternately hard/loose stools, and self-assessed depression were found to be predictors. Pain in the lower arm and a feeling of swelling were more weakly associated. In women with limited pain, pain > or = 6 years' duration, > or = 4 associated symptoms, not feeling refreshed in the morning, and paresthesia were found to be predictors. A weaker association was found with self-assessed depression and a lack of formal education.

CONCLUSION

A high cumulative incidence of FM was found and a diversity of predictors for FM were identified in the total sample and also in women with limited pain. Of the variables that were part of the FM syndrome, back pain predicted FM, while tender points and pain in the neck did not. Moreover, > or = 4 associated symptoms, self-assessed depression, and longlasting pain were shown to be important predictors.

Myopathy and neuropathy in rheumatoid arthritis. A quantitative controlled electromyographic study

OBJECTIVE

To test the hypothesis that patients with rheumatoid arthritis (RA) have clinical or subclinical evidence of peripheral neuropathy or myopathy.

METHODS

We studied 40 seropositive women with RA, mean age 46.6 years (SD 6.4), and 56 healthy controls, mean age 43.0 years (SD 9.1). Patients had a mean disease duration of 13.0 years (SD 7.8). We performed electromyographic examination of 4 muscles [extensor digitorum communis (EDC), biceps brachii (BB), vastus lateralis (VL), and tibialis anterior (TA)] on the right side in both groups. Quantitative data included percentage of polyphasic potentials, motor unit potential amplitude, area, duration, turns, and number of polyphasic potentials.

RESULTS

There were statistically significantly higher proportions of polyphasic potentials in 3 muscles in patients compared with controls. Mean number of phases in EDC was 4.6 (SD 0.4) in the patients and 4.1 (0.5) in controls (p = 0.0001). The values for the VL were 4.1 (SD 0.4) in patients compared with 3.6 (0.4) in controls (p = 0.0001), and in the TA 4.5 (SD 0.5) versus 4.0 (0.4) (p = 0.0001). We also found significantly increased duration of motor unit potentials in the VL and TA of patients. The amplitudes of motor unit action potentials were not significantly different in the 2 groups.

CONCLUSION

The study reveals an increased prevalence of neurogenic but not myogenic changes in patients with RA compared with controls.

Oral and ocular sicca symptoms and findings are prevalent in systemic lupus erythematosus

The aims of this study were 1) to examine the frequency of oral and ocular sicca symptoms in patients with systemic lupus erythematosus (SLE); 2) to compare saliva and tear volume, salivary proteins, and features of the oral microflora and mucosa to a matched healthy control group; and 3) to relate the findings to disease parameters. Median disease duration was 5.5 (0.5-28) years, disease activity 5 (2-20), damage score 1 (0-7), and Schirmer I test 7.5 (0-30 mm). Seventeen and twelve patients complained of oral and ocular dryness, respectively. Unstimulated whole saliva and proline-rich proteins in submandibular saliva were significantly reduced in SLE. Oral microbial counts were generally higher in the patients than controls, and the number of oral mucosal changes was increased. The results show that sicca symptoms, although frequent, were not correlated to secretory rates of saliva or tears, but to oral microbial counts. There was no obvious correlation to patient's age, disease activity or duration.

Health status in systemic lupus erythematosus compared to rheumatoid arthritis and healthy controls

OBJECTIVE

To examine health status in systemic lupus erythematosus (SLE), using both generic and arthritis-specific instruments, and compare the health status in patients with SLE to matched patients with rheumatoid arthritis (RA) and matched healthy controls. As well, to study possible correlations between health status measures and demographic and disease variables in the patients with SLE.

METHODS

Patients were recruited from the Oslo county registers of patients with SLE and RA, and the healthy controls from the county population register. Measures of health status (Medical Outcome Survey SF-36, joint pain and fatigue on visual analog scale, Modified Health Assessment Questionnaire) were obtained from 82 SLE and 82 RA patients matched for age, sex, and disease duration, and from 74 age and sex matched healthy controls. Disease activity and organ damage were assessed in the patients with SLE.

RESULTS

Patients with SLE were significantly more affected in all dimensions of health status compared to controls, except in the SF-36 category role-emotional. Further, patients with SLE were significantly less affected than patients with RA with regard to physical function and joint pain, but scores were similar in all other dimensions of health status. Scores of health status correlated more strongly to the damage index than to disease activity, indicating that health status measures capture some of the same concept as the damage index, namely the consequence of the disease over time.

CONCLUSION

Our study showed that patients with SLE and RA have a multidimensional involvement of health status compared to healthy controls. The findings call for a biopsychosocial approach in the management of SLE.

Cerebral computed tomography and electroencephalography compared with neuropsychological findings in systemic lupus erythematosus

Central nervous system involvement was evaluated in 36 patients with systemic lupus erythematosus (SLE) using cerebral computed tomography (CT), electroencephalography (EEG), and a neuropsychological test battery. The purpose was to investigate whether brain dysfunction as assessed by comprehensive neuropsychological investigation is associated with findings of routine investigation methods such as CT and EEG which are available in most hospitals. Abnormal EEG was found in 19%, and CT revealed cerebral atrophy in 47% of SLE patients. Few neuropsychological functions were affected by the presence of abnormal EEG, cerebral atrophy, or infarcts. Significant associations were found only between cortical atrophy and impairment of tactile spatial problem-solving and motor dexterity, and between cortical infarcts and motor dexterity in the dominant hand. The value of conventional EEG in assessing cerebral SLE is negligible, except for identifying epileptic activity and focal pathology. Cerebral CT has little relevance in predicting brain dysfunction as established by neuropsychological assessment in SLE, except for detecting cortical atrophy and infarcts.

Application of the 1982 revised criteria for the classification of systemic lupus erythematosus on a cohort of 346 Norwegian patients with connective tissue disease

By reviewing patient's records, we evaluated the sensitivity and specificity of the 1982 revised classification criteria for systemic lupus erythematosus on a cohort of 346 Norwegian patients with connective tissue disease, seen at a rheumatology referral center in the period 1986-95. The patients with CTD other than SLE were used as controls. The number of the 1982 revised classification criteria for SLE fulfilled by each individual patient was calculated. Fifty-five of the 76 SLE patients (72%) met four or more criteria for SLE, giving a low sensitivity of 72%. Twenty-three of the 270 patients with CTD other than SLE (9%) met four or more criteria for SLE, giving an acceptable specificity of 91%. Applying the "revised/revised 1997 ACR criteria for SLE" the sensitivity would have increased to 78% and the specificity reduced to 89%. The sample of SLE patients was characterized by mild disease with a low proportion of severe internal manifestations.

[Methotrexate and folates in rheumatoid arthritis]

The efficacy of weekly low-dose methotrexate treatment of rheumatoid arthritis is well documented. Efficacy and adverse events are both dose dependent, and side effects rather than lack of response are the main reason for discontinuing therapy. Several adverse effects appear to be related to folate deficiencies, and are largely due to the antifolate properties of methotrexate. In order to diminish side effects without compromising drug efficacy, clinical trials have been performed using folic acid or folinic acid concomitantly with methotrexate. Important to this achievement are both the timing of folate supplementation and the weekly folate-to-methotrexate ratio. Considering these and other factors, an individually adjusted supply of folic acid is proposed. For several patients a properly balanced diet is sufficient; they do not need additional folate supplements when using methotrexate.

Emotional status in systemic lupus erythematosus

Psychological and emotional status was assessed in 36 patients with systemic lupus erythematosus (SLE) with the General Health Questionnaire-30 (GHQ-30) and Minnesota Multiphasic Personality Inventory (MMPI) questionnaires. The two tests were found to measure different aspects of psychological functioning. More than 50% of the patients could be classified as cases with mild psychiatric disturbances, according to the GHQ, and 28% had an abnormal score > 70 on the MMPI depression subscale, indicating significant depression. Emotional disturbances such as problems with social functioning, personal discomfort in social situations, and depressive mood, were frequent and associated with skin and joint abnormalities. This suggests additional etiologies for psychological dysfunction among SLE patients other than the direct central nervous system (CNS) effect of SLE.

Chronic arthritis and gamma heavy chain disease: coincidence or pathogenic link?

In 1991, gamma heavy chain disease was diagnosed in a 43-year-old female, who 3 years earlier had contracted an erosive seronegative chronic arthropathy. Her gamma heavy chain disease had a benign course, requiring no specific therapy for 5 years. In 1996, however, her lymphoproliferative disorder underwent a more malignant course, with renal and cardiac failure and increasing articular problems, requiring treatment with melphalan and prednisolone, following the protocol for myelomatosis. Laboratory studies revealed a monoclonal component in serum and urine. consistent with dimers of gamma-chains of the gamma3 subclass, but with a smaller molecular mass than normal gamma3-chains, suggesting molecular aberrations as consistently observed in this disorder. Massive localization of plasma cells and blasts with cytoplasmic or cell membrane staining for gamma3-chains, but no staining for kappa or lambda light chains, was observed by immunohistochemical studies of tissue specimens from bone marrow as well as affected synovial tissue. Large amounts of extracellular gamma3-chains were deposited in the synovial membrane. In addition, marked inflammatory changes with synovial cell hyperplasia were seen. Whether the present case represents primarily a gamma heavy chain deposition disease with reactive inflammatory changes in the joints, or another example of gamma heavy chain disease preceded by seronegative rheumatoid arthritis, remains elusive. Regardless, a possible pathogenic link between the two disease processes is an intriguing possibility.

Clinical, epidemiologic, and therapeutic aspects of ankylosing spondylitis

Ankylosing spondylitis (AS) almost invariably starts before the age of 50, and clinical features suggestive of AS in older age should lead to consideration of other rheumatic disorders. Clinical manifestations of extraskeletal tissue such as renal amyloidosis and lung disease may occur. However, the detection of amyloidosis may not invariably infer poor prognosis, and associated lung disease may include apical fibrosis and also interstitial lung disease. Although the clinical significance and pathogenesis of osteoporosis in AS remain unclear, reduced bone mass may be found in a significant number of patients. Population surveys on AS have shown a correlation between the population frequency of HLA B27 and prevalence of AS. However, neither B27 subgroup distribution nor low frequency of B27 can explain the rarity of AS among certain African regions. Also representing an area of future research is the detection of both disease-related variables and sociomedical factors influencing the final outcome of this disease.

Treatment of amyloidosis and the rheumatologist. State of the art and perspectives for the future

The rheumatologist must be prepared to face diagnostic and therapeutic problems related to different categories of amyloidosis. This applies to the systemic AA amyloidosis that complicates chronic inflammatory arthropathies like adult and juvenile rheumatoid arthritis, causing nephropathy and various internal manifestations. Other types of amyloidosis are essential because they may localize to structures of the locomotor system and cause rheumatic complaints. At present, there is no cure for amyloidosis. But adequate and especially early therapeutic intervention is helpful in many cases. This review focuses on treatment of the categories of amyloidosis which are most relevant to the rheumatologist. In addition to treatments that are available today, more effective therapeutic modalities which hopefully will be available in the near future are also reviewed.

Wegener's granulomatosis: long-term follow-up of patients treated with pulse cyclophosphamide

Treatment with daily oral cyclophosphamide (CY) has improved survival in Wegener's granulomatosis (WG), but is associated with severe and potentially lethal adverse effects. Less toxic treatment regimens, such as pulse CY, have been used, but the effect has been questioned. We have treated 11 patients with WG with pulse CY (15 mg/kg initially every second week, gradually increasing the pulse interval). After 4.5 yr follow-up and a total of 501 pulses of CY, one patient died and eight patients (73%) were in complete remission. Remission was induced in 91% of the patients after a median period of 3.5 months and relapses were seen in 60%. With the same treatment protocol, a new complete remission was induced in 75% of those relapsing. Except for one patient who died, no patient developed end-stage renal failure. Haemorrhagic cystitis was not observed and no malignancies recorded. Severe infections were seen in 36%, but none caused by Pneumocystis carinii. Nausea was the most frequent side-effect, seen in 64% of the patients. We conclude that treatment with pulse CY every second week is safe and effective in inducing remission and treating relapses in WG. The relapse rate seems to be higher than with low-dose oral CY, but the cumulative dose of CY is less.

A two-dimensional electrophoretic study of serum amyloid A and C-reactive protein in infants and children

Two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) was used to analyze C-reactive - (CRP) and serum amyloid A protein (SAA) in infants and children. Five SAA isotypes were identified. CRP showed vertical streaking, and its optical density values correlated with immunoturbidimetric measurements. As evaluated by densitometry, both proteins showed an age-dependent variation. In more than 50% of the neonates, SAA was present in equal or higher amounts than CRP, and only SAA1alpha could be detected. In children, CRP was expressed in higher amounts than SAA, and both SAA1alpha and SAA2alpha were present. N-terminally modified forms of both isotypes were present regardless of age, including in premature infants. These results suggest that the overall synthesis of the gene products SAA1alpha and SAA2alpha is developmentally regulated, but at the same time that their N-terminal processing occurs independently of developmental factors. The presented data suggest that SAA has an important function in neonates, and that the role of SAA as an infection marker in this population should be investigated further.

A glycosylated Bence Jones protein and its autologous amyloid light chain containing potentially amyloidogenic residues

Amyloidosis is characterized by deposition of protein fibrils in various tissues. The wide variety of sequences of both amyloidogenic and non-amyloidogenic immunoglobulin light chains makes them a unique tool for addressing the importance of primary structure in the formation of insoluble fibrils. In this study, we have determined the primary structure of the kappa I immunoglobulin light chain from both the urinary Bence Jones protein and the deposited amyloid fibrils of a patient (MH) with primary amyloidosis. The sequence identity of urinary-excreted and tissue-deposited light chains excluded biclonality and somatic mutations and confirmed that the light chain existed in both a soluble and an insoluble form. Several residues have been previously reported to be significantly associated with amyloidogenic kappa chains. Many of these were found in the MH sequence, including Asp31, Asn45, Phe49, Gln55, His70, Asn/Gly93 and ProN/Val96, thereby supporting their potential role in fibrillogenesis. In addition, Asn20 and Pro60 of protein MH replaced the normally conserved Thr20 and Ser60. Asn20 was glycosylated in both the Bence Jones and the amyloid fibril protein MH. Cumulative effects of amyloid-associated residues and glycosylation might have rendered the immunoglobulin light chain MH prone to fibril formation.

A population study of the incidence of fibromyalgia among women aged 26-55 yr

In a population survey, we assessed the incidence of fibromyalgia (FM) among females. A screening questionnaire about pain was distributed twice (in 1990 and 1995) to 2498 females aged 20-49 yr, living in South Norway. A positive answer classified the responder as positive, merely negative answers as negative. One hundred females converting from negative to positive responders and 100 females remaining negative responders (controls) underwent a structural interview and examination for tender points (TP). Of the 870 negative responders in 1990, 717 answered the questionnaire in 1995. Of these, 523 were still negative responders, while 194 were positive converters. Twelve of the converters developed FM and none of the controls. The calculated annual incidence of FM in females was 583/100,000. This rather high incidence is most likely explained by the design of the study, also detecting cases usually not seen in hospital settings.

The amino acid sequence of the glycosylated amyloid immunoglobulin light chain protein AL MS

The authors report on the amino acid sequence of the glycosylated amyloid protein AL MS. The amyloid fibrils were extracted from the spleen of a patient (MS.) with amyloidosis. The protein AL MS was purified from the amyloid fibrils by gel filtration. SDS-PAGE performed on the purified protein material showed glycosylated protein bands in the range of 22 to 32 kDa, corresponding to polymerization of N-terminal fragments. The protein was characterized by amino acid analysis and Edman degradation. Tryptic digest combined with Staphylococcal V8 protease, chymotrypsin and pyroglutamate aminopeptidase digestion, as well as cleavage with BNPS-skatole, established the complete amino acid sequence of 168 residues. The protein was compared to other proteins in the SWISSPROT databank, showing homology with the immunoglobulin light chain variable subgroup lamda I. AL MS showed some unique amino acid substitutions. Highly conserved residues Gly(57) and Arg(61), were exchanged to arginine and glutamine, respectively, possibly altering the three- dimensional structure of the protein.

The rheumatoid wrist: bilateral MR analysis of the distribution of rheumatoid lesions in axial plan in a female population

In this case-control study, we analyzed 146 wrists: a) to search for the distribution pattern of the rheumatoid lesions and, b) to correlate the distribution pattern of these lesions with the clinical parameters. Thirty-one patients with rheumatoid arthritis (RA) and 42 controls-all women-were examined by means of a bilateral MR fast field echo (FFE) sequence, in axial plan. The wrist was divided into three regions: metacarpal (level I), carpal (level II) and radioulnar (level III). Erosions were present in thirty (97%) patients and in six (14%) controls. They were asymmetrically distributed at all levels, mainly at level II. Marrow infiltration and bone destruction were seen in 35% of the patients in an asymmetrical pattern at level I and II, respectively. These lesions were absent in the control group. Subchondral cysts were asymmetrically present in both groups-in 48% of the patients at levels II and III, and in 11% of the controls at level II. In the patient group, this asymmetrical pattern of the lesions correlated with the disease duration at levels I and II (p = 0.011 and p = 0.013, respectively). Most lesions were found at the radial force-bearing column of the wrist, more in the right side. Synovial hypertrophy and hyperintense median nerve were evident in 96% and 70% of the patients, respectively. We concluded that contrary to common belief rheumatoid damages to the carpal bones become rather asymmetrical as the disease progresses. The line of force along the radial side of the wrist possibly influences the distribution pattern of the rheumatoid lesions.

C-fibre function in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) frequently involves the central nervous system (CNS), but to a considerably lesser degree leads to peripheral neuropathy as measured by conventional nerve conduction velocity studies. Neuropathic symptoms are, however, frequently reported. Abnormalities of other nerve fibers than the large myelinated nerves might thus be responsible for such phenomena. Three age matched groups of 44 patients with SLE, 50 patients with rheumatoid arthritis (RA) and 45 healthy controls were investigated with quantitative sensory thermotesting. Warm detection thresholds (WDT) and heat pain detection thresholds (HPDT) were found significantly higher in SLE compared to RA and controls. There were no differences between the RA and the control group. In the SLE group no association to disease duration, medication or CNS abnormalities were found. Neuropathic symptoms and vibration thresholds showed weak associations to WDT. These findings imply that there is an impairment of C-fibre function in SLE. This small fibre neuropathy is probably not part of a generalized diffuse polyneuropathy also affecting large fibres, although this can not be ruled out completely by this study.