Raynaud's phenomenon and its impact on activities in daily life during one year of follow-up in early systemic sclerosis.

OBJECTIVE: To investigate Raynaud's phenomenon (RP) and its impact on daily life activities during 1 year of follow-up in early systemic sclerosis (SSc). METHOD: Fourteen SSc patients with a median disease duration of 2 years were enrolled in the study. Every 7 weeks the patients completed a 7 day diary documenting the frequency and duration of RP attacks, the activity causing the attack, and how they handled the attack. The patients also recorded in the diary daily self-assessments of the difficulties with RP, using a 0-10 ordinal scale according to the Raynaud's Condition Score. RESULTS: Ninety-eight RP weekly diaries were analysed. The median number of RP attacks varied between six and nine per week, and the median score reflecting the difficulty associated with the attacks varied between 2.0 and 2.9. No difference was found in the number of attacks or the difficulties associated with them between winter, spring, and autumn. Fewer attacks and less difficulty were reported in August than in any of the other documented weeks (p < 0.05). In all diaries, all patients reported RP attacks associated with domestic activities. The use of heating devices varied during the follow-up. In February, all patients except one used such devices, while about half of the group used devices during the rest of the year. CONCLUSIONS: Difficulties resulting from RP are present and disabling all year round, which underscore the importance of intense vasoactive therapy and non-pharmacological strategies throughout the year.

CD81 and CD48 show different expression on blood eosinophils in systemic sclerosis: new markers for disease and pulmonary inflammation?

OBJECTIVES: In systemic sclerosis (SSc)-related interstitial lung disease (ILD), elevated eosinophil counts in bronchoalveolar lavage are associated with a worse outcome. We hypothesized that eosinophils may be activated in the peripheral circulation, thereby increasing their recruitment to affected tissues and contributing to inflammation and fibrosis. The aim of this study was to characterize the blood eosinophils in SSc patients. METHOD: Expression levels of surface markers CD11b, CD44, CD48, CD54, CD69, CD81, and HLA-DR on CD16(low)CD9(high)-expressing eosinophils were measured by flow cytometry in whole blood from SSc patients (n = 32) and controls (n = 11). RESULTS: Expression levels of CD54, CD69, and HLA-DR were undetectable in all groups. CD44 and CD11b expression levels were similar between groups. CD81 expression was lower in patients compared to controls independent of disease duration (p = 0.001). CD48 expression was increased in patients with a short disease duration (< 2 years) compared to both controls (p = 0.042) and patients with longer disease duration (≥ 2 years; p = 0.027). In patients with short disease duration, increased CD48 expression was associated with alveolar inflammation as measured by an increased concentration of alveolar nitric oxide (r = 0.76, p = 0.003). CONCLUSIONS: Blood eosinophils change phenotype during disease evolution in SSc, and CD48 expression may be used as a biomarker for pulmonary inflammation.

Vascular events are risk factors for anal incontinence in systemic sclerosis: a study of morphology and functional properties measured by anal endosonography and manometry.

OBJECTIVES: To study anal sphincter morphology, anal sphincter pressure, and rectoanal inhibitory reflex (RAIR) in patients with systemic sclerosis (SSc) complicated by anal incontinence (AI) and to investigate possible risk factors for AI in SSc. METHOD: Nineteen SSc patients with severe AI were investigated using anal endosonography, anal manometry, and rectal manovolumetry. To determine risk factors for AI, disease characteristics of SSc patients with AI were compared with those of 95 SSc patients without AI; there were five matched SSc patients without AI for each SSc patient with AI. RESULTS: The mean (SD) internal sphincter thickness was 1.3 (0.46) mm in patients with AI, which was thinner (p < 0.001) than reference data from healthy individuals whose internal sphincter measured 2.2 (0.45) mm, whereas the external sphincter thickness did not differ. The mean (SD) resting pressure in AI patients was lower than the reference data from healthy individuals [60 (22) vs. 94 (29) mmHg, p < 0.002] whereas the squeeze pressure did not differ. Centromeric antibodies and features of vascular disease [i.e. the presence of pulmonary arterial hypertension (PAH), digital ulcers, pitting scars, or the need for iloprost infusions] were associated with AI whereas fibrotic manifestations [i.e. modified Rodnan skin score (mRss), the diffuse cutaneous SSc (dcSSc) subset, or low vital capacity (VC)] were not. CONCLUSIONS: SSc patients with AI have a thin internal anal sphincter and a low resting pressure. Risk factors for AI among SSc patients are centromeric antibodies and vascular disease, which supports the hypothesis that gastrointestinal involvement in SSc is in part a vascular manifestation of the disease.

Increased serum type I interferon activity in early systemic sclerosis patients is associated with antibodies against Sjögren's syndrome antigens and nuclear ribonucleoprotein antigens.

OBJECTIVE: To study serum type I interferon (IFN) activity in patients with early systemic sclerosis (SSc). METHOD: Serum type I IFN activity was measured in 33 consecutive patients with SSc and a disease duration of < 2 years and in 13 healthy individuals by calculating a type I IFN score according to the induction of six IFN-α regulated genes in a reporter cell line. RESULTS: Twenty-seven per cent of the SSc patients had an increased type I IFN score compared to none of the healthy individuals (p < 0.05). The clinical SSc phenotype associated with high serum type I IFN activity did not differ from patients with low serum type I IFN activity regarding the presence of skin or lung fibrosis, pulmonary hypertension, or digital complications. Patients with high serum type I IFN activity were younger (p < 0.01) and had a lower frequency of cardiac involvement (p = 0.053), lower leucocyte count (p < 0.001), higher immunoglobulin (Ig)G levels (p < 0.05), and a higher amount of antibodies against extractable nuclear antigens (p < 0.01) than patients with low serum type I IFN activity. The presence of antibodies against topoisomerase I, Sjögren's syndrome antigen, and nuclear ribonucleoprotein antigens was associated with higher type I IFN activity (p < 0.05 for all comparisons). CONCLUSIONS: Our study indicates that increased serum type I IFN activity in early SSc patients is associated with an antibody and laboratory profile that may reflect a subclinical overlap of SSc with other type I IFN-driven connective tissue diseases (CTDs).

Scleroderma renal crisis in a Swedish systemic sclerosis cohort: survival, renal outcome, and RNA polymerase III antibodies as a risk factor.

OBJECTIVES: To study survival, renal outcome, and RNA polymerase III antibodies (RNAP Abs) as a risk factor for scleroderma renal crisis (SRC) in a Swedish cohort of systemic sclerosis (SSc) patients. METHODS: SRC was diagnosed in 16 SSc patients during the period from 1982 to 2010. For comparison, 112 (seven for each SRC patient) SSc patients without SRC were included. RNAP Abs were detected by a fully automated fluoroenzyme immunoassay (EliA). Values greater than 15 µg/L were considered positive. Frozen serum samples from the time of diagnosis of SSc were used. RESULTS: The 5- and 10-year survival rates were, respectively, 58% and 40% for SRC patients and 90% and 76% for patients without SRC (p < 0.001). The odds ratio (OR) for mortality was 4.39 [95% confidence interval (CI) 2.10-9.16, p < 0.001] in patients with SRC compared to those without SRC. Renal outcome was good in three patients. Haemodialysis was started in 10 patients and peritoneal dialysis in three. Renal function improved in three patients and dialysis was terminated. Four patients underwent renal transplantation. Seven SRC patients and nine without SRC were positive for RNAP Abs. Anti-RNAP Abs was a strong predictor of SRC. The sensitivity and specificity for development of SRC were 0.44 and 0.92, respectively. The OR for development of SRC was 8.90 (95% CI 2.68-29.6, p = 0.001) in RNAP-positive patients. CONCLUSIONS: RNAP positivity is a strong risk factor for SRC. Renal outcome was variable and survival is still notably decreased.

Faecal calprotectin: a biomarker of gastrointestinal disease in systemic sclerosis.

BACKGROUND: Assessment of gastrointestinal (GI) involvement in systemic sclerosis (SSc) is difficult. Measurement of calprotectin in faeces is a valuable tool for the assessment of inflammatory bowel diseases. Calprotectin is an intracellular protein found in leucocytes and is a potent activator of the innate immune system. OBJECTIVE: To determine whether faecal calprotectin (F-calprotectin) could serve as a biomarker of GI disease in SSc. DESIGN: In a cross-sectional study, F-calprotectin and plasma calprotectin were measured in patients with SSc using an enzyme-linked immunosorbent assay. F-calprotectin concentrations were evaluated in relation to cineradiography, medical records, laboratory measurements and patients' subjective GI symptoms. SETTING: The study was conducted at a tertiary referral centre for SSc. SUBJECTS: The study comprised 81 consecutive patients with SSc. RESULTS: A majority of the patients had pathological levels of F-calprotectin when compared to accepted clinical reference values for healthy adults. F-calprotectin did not correlate with calprotectin levels in plasma. F-calprotectin was associated with the following patient characteristics: pathological cineradiography, history of referral to another clinic because of GI disease, treatment of vitamin or mineral deficiency and use of proton pump inhibitors. We did not find any significant correlation between F-calprotectin and patient-reported GI symptoms. CONCLUSION: Faecal calprotectin is increased in a majority of patients with SSc. It correlates with objective and clinically important features of GI disease, and faecal concentrations do not vary with plasma concentrations. We suggest that F-calprotectin is a promising objective non-invasive biomarker of GI involvement in SSc.

Enlarged right-sided dimensions and fibrosis of the right ventricular insertion point on cardiovascular magnetic resonance imaging is seen early in patients with pulmonary arterial hypertension associated with connective tissue disease.

OBJECTIVES: To describe the findings of cardiovascular magnetic resonance (CMR) imaging in patients with pulmonary arterial hypertension (PAH) associated with connective tissue disease (CTD) and in consecutive patients with systemic sclerosis (SSc) without PAH. METHODS: The study comprised nine consecutive patients who were admitted for right heart catheterization (RHC) under a suspicion of CTD-PAH and 25 consecutive patients who were admitted for evaluation because of a clinical suspicion of SSc. In addition to the regular assessment, they also underwent examination by CMR. RESULTS: CMR measurements of right ventricular (RV) volumes and function showed severe pathology in patients with CTD-PAH. Patients with SSc without PAH had similar but much less severe findings. Right ventricular end-diastolic volume (RVEDV) and right ventricular ejection fraction (RVEF) were abnormal in all patients with CTD-PAH. In eight out of nine patients with CTD-PAH, fibrosis was seen in the RV insertion point, probably caused by increased tension, but only in one of the consecutive SSc patients. This patient was diagnosed with CTD-PAH 20 months later. CONCLUSIONS: In CTD-PAH, CMR shows severe changes in RV volumes and function, but also fibrosis in the RV insertion point. Similar abnormalities, although much less severe, may be seen at diagnosis of SSc. Further evaluation is warranted to determine whether these findings are of value in screening for early signs of PAH in SSc.

Survival in patients with pulmonary arterial hypertension associated with systemic sclerosis from a Swedish single centre: prognosis still poor and prediction difficult.

OBJECTIVES: To describe the survival rate in a cohort of systemic sclerosis (SSc) patients with pulmonary arterial hypertension (PAH) and to evaluate possible predictors for SSc-PAH in a cohort of SSc patients. METHODS: Thirty patients with SSc-PAH and 150 SSc patients without PAH were included. Survival and survival on therapy were calculated. Clinical features at baseline were correlated to the risk for development of PAH during follow-up. RESULTS: The 1-, 2-, 3-, and 4-year survival rates were 86, 59, 39, and 22%, respectively, from diagnosis of PAH. The hazard ratio for total mortality in the SSc-PAH group was 3.2 [95% confidence interval (CI) 1.8-5.7] compared to SSc without PAH (p < 0.001). Risk factors at baseline for the development of PAH were: limited skin involvement, low diffusing capacity of the lung for carbon monoxide (DL(CO)), high N-terminal pro-brain natriuretic peptide (NTProBNP), increased estimated systolic pulmonary arterial pressure (ESPAP), and the presence of teleangiectases. Severe peripheral vascular disease requiring iloprost treatment during follow-up was associated with an eightfold increased risk of PAH. CONCLUSION: Despite modern treatment and yearly screening by echocardiography, the survival in SSc-PAH is still low in our cohort. The identified risk factors should be assessed to select patients eligible for right heart catheterization (RHC) to make an earlier diagnosis.

Progressive capillary loss over a decade in patients with systemic sclerosis, in particular in patients with early digital ischaemic manifestations.

OBJECTIVE: Characteristic capillary abnormalities occur early in systemic sclerosis (SSc). Our aim was to study the longitudinal development of capillary density in SSc patients. METHODS: Forty-eight consecutive patients with SSc fulfilling a follow-up of at least 8 years were retrospectively analysed for capillary loss over the observation period. Eleven had diffuse cutaneous SSc (dcSSc) and 37 limited cutaneous SSc (lcSSc). The median disease duration at first assessment was 2.5 years. Capillary density was determined by direct counting of capillaries in the distal row on eight fingers in a stereo-zoom microscope at 20× magnification. RESULTS: Capillary density decreased over the observation period in dcSSc (from median 5.1 to 4.4 loops/mm, p < 0.05) and in lcSSc (from 5.1 to 4.2 loops/mm, p < 0.001). No significant difference was found between the two forms at start or at follow-up. Digital ischaemic manifestations had already been found at the first assessment in 19 patients. They did not differ in capillary density from those without ischaemic manifestations at the first assessment (5.0 and 5.3 loops/mm), but did differ at follow-up (3.6 and 4.7 loops/mm, p < 0.001). Capillary loss was more pronounced in patients who already had digital ischaemic manifestations at the first assessment compared to those without (p < 0.02). CONCLUSION: In SSc, early digital ischaemic manifestations may precede a subsequent progressive capillary loss. The association between capillary loss and serious internal vascular complications remains to be studied.

Increased alveolar nitric oxide in early systemic sclerosis.

OBJECTIVES: Assessment of inflammatory activity in interstitial lung disease of systemic sclerosis (SSc) is difficult. Nitric oxide (NO) has gained attention in the pathogenesis of SSc. The aim of the study was to investigate alveolar NO concentration (CA(NO)) in SSc patients with short disease duration and to relate CA(NO) to radiologic findings. METHODS: In a prospective study, 34 consecutive patients with disease duration of less than 2 years from onset of first non-Raynaud symptom and 26 healthy controls were enrolled. Exhaled NO was measured and CA(NO) was calculated. CA(NO) levels were related to the radiologic extent of pulmonary fibrosis measured as the extent of traction bronchiectasis within areas of ground glass opacities and reticulations. RESULTS: CA(NO) levels were increased in patients with early SSc compared to healthy controls (3.52 (2.94-4.09) versus 2.08 (1.6-2.6); p<0.001). Both SSc patients with SSc-ILD (3.56 (3.04-4.73), p<0.001) and SSc patients without SSc-ILD (2.98 (2.68-3.98), p<0.01) had higher CA(NO) levels compared with healthy controls (2.08 (1.6-2.6)). CA(NO) levels did not differ between SSc patients without SSc-ILD and SSc patients with SSC-ILD. CA(NO) levels did not correlate to the extent of pulmonary fibrosis but were associated with the extent of ground glass opacities (rs=0.37, p<0.05) and reticulations (rs=0.37, p<0.05) on HRCT. CA(NO) levels were not correlated to lung function tests. CONCLUSIONS: In patients with early SSc, alveolar NO is increased and may precede radiological changes of SSc-ILD. CA(NO) may therefore be a marker of early lung involvement.

Renal function is mostly preserved in patients with systemic sclerosis.

OBJECTIVE: Chronic renal disease other than scleroderma renal crisis (SRC) is not well documented in systemic sclerosis (SSc). We examined the occurrence of decreased glomerular filtration rate (GFR) in a large consecutive SSc cohort and analysed whether it was related to SSc or could be related to other causes. METHODS: During 1983-2004 GFR was measured by chromium-51-ethylenediaminetetraacetic acid (51Cr-EDTA) or iohexol clearance in 461 patients with SSc according to the American College of Rheumatology (ACR) criteria [356 with limited cutaneous SSc (lcSSc) and 105 with diffuse cutaneous SSc (dcSSc)] and the measurements were repeated once a year. Decreased GFR was defined as GFR<70% of the age-adjusted values. SRC was diagnosed in 4/360 lcSSc (1.1%) and in 10/115 dcSSc (8.7%). These patients were excluded from further analyses. RESULTS: At the latest follow-up at a median duration of 7.7 (range 0.5-54) years, decreased GFR was found in 39 lcSSc (11%) and nine (8.6%) dcSSc patients. Among the 48 SSc patients with GFR< 70p% (percentage of predicted value = p%), hypertension was diagnosed in 29 (60%) and cardiac involvement in 25 (52%). Different nephropathies were found in eight (19%) patients by renal biopsy. Fifteen patients with decreased GFR were followed up for > or = 4 years and no progress was seen in 11/15. CONCLUSIONS: A minority of patients with SSc develop renal dysfunction other than SRC. Decreased GFR was associated with other manifestations such as hypertension and cardiac involvement indicating possible pre-renal causes.

Working ability in relation to disease severity, everyday occupations and well-being in women with limited systemic sclerosis.

OBJECTIVE: To investigate how women with SSc and varying degrees of working ability differed regarding disease severity, everyday occupations and well-being. Working ability was operationalized according to the degree of sick leave. METHODS: Forty-four women of working age with lcSSc were assessed regarding sociodemographic characteristics, disease severity including organ manifestation, perceived physical symptoms, hand function, and satisfaction with everyday occupations, self-rated health and well-being. RESULTS: The subjects formed three groups with regard to reduction in working capacity. Twenty-one women (48%) had no sick leave, 15 women (34%) were on partial sick leave and eight women (18%) were temporarily on full-time sick leave or had a full disability pension. There were no statistically significant differences concerning sociodemographics between the groups. Women without sick leave had less physically demanding jobs (P = 0.026), and the hypothesis that working ability reflects lower disease severity was confirmed regarding dexterity grip force and perceived fatigue and breathlessness (P < 0.05). Greater working ability was associated with better capacity to perform activities of daily life (P < 0.01), greater satisfaction with occupations (P < 0.01), better well-being (P < 0.001) and better health (P < 0.001). CONCLUSIONS: Fifty per cent of the women were restricted in their working ability; the lower the working ability, the lower their perceived well-being. This emphasizes the need for further research into the factors that promote working ability and the development of suitable methods to improve working ability.

High-frequency ultrasound of skin involvement in systemic sclerosis reflects oedema, extension and severity in early disease.

OBJECTIVE: The aim was to compare skin assessment by palpation and by high-frequency ultrasound in patients with SSc with disease duration <2 yrs. METHODS: Skin thickness and skin echogenicity were measured by 20 MHz ultrasound at five different anatomical sites in 106 individuals within 2 yrs from the first non-Raynaud's symptom and compared with the modified Rodnan skin score (mRss). RESULTS: The patients with short disease duration were characterized by high skin thickness and low skin echogenicity, which correlated inversely, reflecting oedema. Patients with diffuse skin involvement displayed higher skin thickness and lower skin echogenicity than did patients with limited skin involvement. The ultrasound measurements correlated to the local mRss from the corresponding anatomical region and also to the total mRss. However, there was a considerable overlap in both skin thickness and skin echogenicity between different local mRss at all five anatomical sites. Skin involvement of the chest could be detected earlier by ultrasound than by palpation. CONCLUSION: In SSc patients with short disease duration, high-frequency ultrasound can identify the oedematous phase that may precede palpable skin involvement and may thus be useful to identify patients with diffuse skin involvement very early in the disease process. Ultrasound measurements also reflect the severity of the overall skin involvement.

Esophageal scintigraphy of systemic sclerosis.

UNLABELLED: Esophageal involvement is common in systemic sclerosis, and esophageal scintigraphy can be used to detect and follow esophageal dysfunction. This study assesses the value of visual and quantitative analysis of esophageal scintigraphy performed as a multiple swallow test in normals and patients with systemic sclerosis. METHODS: Forty patients with systemic sclerosis and 40 sex- and age-matched healthy subjects (controls) were studied. A multiple swallow technique was used and both quantitative and qualitative analyses were performed. Visual analysis of condensed images was performed independently by two physicians. Each swallow was assigned a score on a scale from 1 to 4. In the quantitative analysis, time-activity curves based on the mean condensed images were used to calculate the following 3 parameters: residual activity 12 or 25 sec after the beginning of the swallow, measured with or without baseline correction, respectively, and time from onset of swallow to 50% of peak activity. RESULTS: Both visual and quantitative analysis showed a highly significant (p < 0.001) difference between the patient group and the control group. Visual analysis was best reflected by the residual activity 25 sec after the beginning of the swallow without correction for background. Receiver operating characteristic curves were used to study the ability to separate the two groups using visual or quantitative analysis. A high rate of positive tests in the patient group was achieved only at the cost of a relatively high rate of positive tests in the control group. CONCLUSION: Our results indicate high variability in esophageal motility in controls. This variability impairs the possibilities of developing a screening test to identify asymptomatic patients early in the disease course.

Experience with a skin chamber technique for leucocyte migration studies.

An in vivo skin chamber method using lesions obtained by suction was evaluated. Neither dyspigmentation nor scarring were seen after 2 mth. The number of leucocytes accumulated in the collection chamber was correlated to the area of the lesion. Reproducibility remained essentially unchanged over an extended period and was 19% for one chamber and 13.6% for determinations with two chambers. No correlation was found between results obtained with the skin chamber technique and with chemotaxis or random migration as determined by an underagarose technique. When factors influencing in vivo and in vitro migration were studied, it was found that nonsteroidal anti-inflammatory drugs when given to arthritis patients or healthy volunteers inhibit leucocyte migration in vivo while in vitro migration was unchanged. Activated serum and LTB4 attracted leucocytes both in vivo and in vitro. The attraction by serum appeared at least partly to be caused by C5a. Polymorphonuclear leucocytes harvested from skin chambers were chemotactically deactivated and their bactericidal capacity reduced. The chemiluminescent response to formyl-methionyl-leucyl-phenylalanine and opsonized zymosan was increased. Exposed to zymosan activated serum, blood leucocytes showed a similar functional modification as leucocytes harvested from a skin chamber, and our findings suggest that the altered function of leucocytes in an inflammatory focus is largely the result of their exposure to chemotactic factors.

Effect of LTB4 and its isomers on human leucocyte migration into skin chambers.

The in vivo chemotactic effect of LTB4 and of its isomers, 6-trans-LTB4, 12 epi-6-trans-LTB4 and 5S, 12S-DHETE, was tested with a skin chamber technique in healthy volunteers and in parallel in vitro with an under-agarose technique. LTB4 had an in vivo chemotactic effect at 10(-7) mol/l in 24-hour experiments, while its isomers had no in vivo chemotactic effect at this concentration. LTB4 was also in vitro a more effective attractant than its isomers. In addition, C5ades Arg was tested using zymosan-activated serum, and was found to have an in vivo chemotactic effect at 1.5 X 10(-10) mol/l. However, when LTB4 and C5ades Arg were studied in 6-hour experiments in skin chambers there was an alteration in relative potency, LTB4 being relatively more potent at shorter test durations. This is most likely due to metabolisation of LTB4 in the presence of PMN:s and precludes a strict comparison of the in vivo chemotactic effects of LTB4 and C5ades Arg. When zymosan-activated serum or LTB4 was replaced by PBS after six hours in skin chamber experiments more leukocytes accumulated in the chambers at 24 hours than in chambers containing PBS for the whole 24 hour period. The reason for the increased migration even after the removal of the chemo-attractants as well as the relevance of LTB4 and C5a as chemo-attractants in the inflammatory process is discussed.

Comparison of high frequency (20 MHz) ultrasound and palpation for the assessment of skin involvement in systemic sclerosis (scleroderma).

BACKGROUND AND OBJECTIVES: Systemic sclerosis (SSc) is a connective tissue disease characterized by microvascular changes and fibrosis of the skin and internal organs. Increased skin thickness proximal to the metacarpophalangeal joints is the single major diagnostic criterion. The aim of this study was to evaluate high frequency (20 MHz) ultrasound for the assessment of skin thickness in patients with SSc of different disease durations. METHODS: Skin thickness was measured with high frequency (20 MHz) ultrasound equipment (Dermascan) in 41 patients with SSc (23 women and 18 men) and in 41 controls. Twenty-five patients had limited cutaneous systemic sclerosis (ISSc), 12 had diffuse cutaneous systemic sclerosis (dSSc) and 4 had suspected SSc. RESULTS: Skin thickness of the forearm was inversely correlated to disease duration. Compared to controls, skin thickness was increased over the proximal phalanx of the right second finger and over the forearm in patients with a disease duration of 2 years or less. Assessments of skin thickness in 10 controls by 2 independent investigators showed an inter-observer variability of 1.0% for the proximal phalanx and 0.0016% for the forearm. Patients whose ultrasound showed increased skin thickness on the hand and forearm also had thickened skin by palpation. CONCLUSION: High frequency (20MHz) ultrasound is a feasible method for measuring skin thickness in SSc, and may be useful for diagnosis, long-term follow-up, and assessment in therapeutic studies.

Kinetics of enzymes released from polymorphonuclear leucocytes in a skin chamber.

Ten healthy volunteers were investigated with a skin chamber technique developed for leucocyte migration studies. Chambers, filled with autologous serum, were harvested at 4, 8, 12, 22, and 30 hours. A marked increase was found both in the concentration of elastase in chamber serum as measured by RIA, and of lysozyme as measured both with lysoplate and electroimmuno assays. The immuno-reactive elastase was shown to consist exclusively of elastase-alpha 1-proteinase-inhibitor complexes. During the first 22 hours the concentrations of elastase and lysozyme were roughly proportional to the number of cells in the skin chamber (r = 0.92 and 0.85). At longer incubation times there was a decrease of relative concentration of elastase but not of lysozyme. Lactate dehydrogenase (LDH) was measured as a marker of the lysis of chamber leucocytes. Lysis was less than 1.5% at all incubation times. The present study shows a release of elastase from primary granules and of lysozyme when polymorphonuclear leucocytes migrate into a skin chamber.