The role of lung biopsy for diagnosis and prognosis of interstitial lung disease in systemic sclerosis: a systematic literature review.

BACKGROUND: The prognostic and theragnostic role of histopathological subsets in systemic sclerosis interstitial lung disease (SSc-ILD) have been largely neglected due to the paucity of treatment options and the risks associated with surgical lung biopsy. The novel drugs for the treatment of ILDs and the availability of transbronchial cryobiopsy provide a new clinical scenario making lung biopsy more feasible and a pivotal guide for treatment. The aim of our study was to investigate the usefulness of lung biopsy in SSc ILD with a systematic literature review (SLR). METHODS: PubMed, Embase and Cochrane databases were searched up to June 30, 2023. Search terms included both database-specific controlled vocabulary terms and free-text terms relating to lung biopsy and SSc-ILD diagnostic and prognosis. The SLR was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). Studies were selected according to the PEO (population, exposure, and outcomes) framework and Quality assessment of diagnostic accuracy studies (QUADAS) were reported. RESULTS: We selected 14 articles (comprising 364 SSc-ILD patients). The paucity and heterogeneity of the studies prevented a systematic analysis. Diffuse cutaneous SSc was present in 30-100% of cases. Female predominance was observed in all studies (ranging from 64 to 100%). Mean age ranged from 42 to 64 years. Mean FVC was 73.98 (+/-17.3), mean DLCO was 59.49 (+/-16.1). Anti-Scl70 antibodies positivity was detected in 33% of cases (range: 0-69.6). All patients underwent surgical lung biopsies, and multiple lobes were biopsied in a minority of studies (4/14). Poor HRCT-pathologic correlation was reported with HRCT-NSIP showing histopathologic UIP in up to 1/3 of cases. Limited data suggest that SSc-UIP patients may have a worse prognosis and response to immunosuppressive treatment compared to other histopathologic patterns. CONCLUSIONS: The data from this SLR clearly show the paucity and heterogeneity of the studies reporting lung biopsy in SSc ILD. Moreover, they highlight the need for further research to address whether the lung biopsy can be helpful to refine prognostic prediction and guide therapeutic choices.

Tenosynovial complications identify TTR cardiac amyloidosis among patients with hypertrophic cardiomyopathy phenotype.

Recent evidence suggests that carpal tunnel syndrome (CTS) and brachial biceps tendon rupture (BBTR) represent red flags for ATTR cardiac amyloidosis (ATTR-CA). The prevalence of upper limb tenosynovial complications in conditions entering differential diagnosis with CA, such as HCM or Anderson-Fabry disease (AFD), and hence their predictive accuracy in this setting, still remains unresolved. OBJECTIVE: To investigate the prevalence of CTS and BBTR in a consecutive cohort of ATTR-CA patients, compared with patients with HCM or AFD and with individuals without cardiac disease history. PARTICIPANTS: Consecutive patients with a diagnosis of ATTR-CA, HCM and AFD were evaluated. A control group of consecutive patients was recruited among subjects hospitalized for noncardiac reasons and no cardiac disease history. The presence of BBTR, CTS or prior surgery related to these conditions was ascertained. RESULTS: 342 patients were prospectively enrolled, including 168 ATTR-CA (141 ATTRwt, 27 ATTRm), 81 with HCM/AFD (N = 72 and 9, respectively) and 93 controls. CTS was present in 75% ATTR-CA patients, compared with 13% and 10% of HCM/AFD and controls (P = 0.0001 for both comparisons). Bilateral CTS was present in 60% of ATTR-CA patients, while it was rare (2%) in the other groups. BBTR was present in 44% of ATTR-CA patients, 8% of controls and 1% in HCM/AFD. CONCLUSIONS: CTS and BBTR are fivefold more prevalent in ATTR-CA patients compared with cardiac patients with other hypertrophic phenotypes. Positive predictive accuracy for ATTR-CA is highest when involvement is bilateral. Upper limb assessment of patients with HCM phenotypes is a simple and effective way to raise suspicion of ATTR-CA.

Use of vasoactive/vasodilating drugs for systemic sclerosis (SSc)-related digital ulcers (DUs) in expert tertiary centres: results from the analysis of the observational real-life DeSScipher study.

INTRODUCTION: DeSScipher is the first European multicentre study on management of systemic sclerosis (SSc), and its observational trial 1 (OT1) evaluated the efficacy of different drugs for digital ulcer (DU) prevention and healing. The aim of this study was to assess current use of vasoactive/vasodilating agents for SSc-related DU in the expert centres by analysing the baseline data of the DeSScipher OT1. METHOD: Baseline characteristics of patients enrolled in the OT1 and data regarding DU were analysed. RESULTS: The most commonly used drugs, in both patients with and without DU, were calcium channel blockers (CCBs) (71.6%), followed by intravenous iloprost (20.8%), endothelin receptor antagonists (ERAs) (20.4%) and phosphodiesterase 5 (PDE-5) inhibitors (16.5%). Of patients, 32.6% with DU and 12.8% without DU received two drugs (p < 0.001), while 11.5% with DU and 1.9% without DU were treated with a combination of three or more agents (p < 0.001). Sixty-five percent of the patients with recurrent DU were treated with bosentan and/or sildenafil. However, 64 out of 277 patients with current DU (23.1%) and 101 (23.6%) patients with recurrent DU were on CCBs alone. CONCLUSIONS: Our study shows that CCBs are still the most commonly used agents for DU management in SSc. The proportion of patients on combination therapy was low, even in patients with recurrent DU: almost one out of four patients with current and recurrent DU was on CCBs alone. Prospective analysis is planned to investigate the efficacy of different drugs/drug combinations on DU healing and prevention. Key Points • The analysis of DeSScipher, the first European multicentre study on management of SSc, has shown that the most commonly used vasoactive/vasodilating drugs for DU were CCBs, followed by intravenous Iloprost, ERAs and PDE-5 inhibitors. • More than half of the patients with recurrent DU received bosentan and/or sildenafil. • However, the proportion of patients on combination therapy of more than one vasoactive/vasodilating drug was low and almost one out of four patients with current and recurrent DU was on CCBs alone.

The safety of iloprost in systemic sclerosis in a real-life experience.

Iloprost (ILO) is employed intravenously for the treatment of severe Raynaud phenomenon (RP) and digital ulcers (DU) in systemic sclerosis (SSc). The aim of this study was to evaluate the safety and tolerability of the intravenous treatment with ILO in different phases of SSc. Eighty-one consecutive non-selected SSc patients, all on nifedipine, with moderate RP, treated with ILO infusion, were retrospectively evaluated. Patients were sub classified according to the edematous or fibrotic/atrophic cutaneous phase of the disease. ILO was infused with a progressive increase of the dosage up to the achievement of patient's tolerance, 1 day/week. In cases of slower infusion regimen due to adverse events (AE) at the beginning of the administration, patients received a lower dose of the drug (not possible to quantify precisely the final cumulative dosage). 16/81 SSc patients presented digital edema, 5 developed diarrhea, and 9 developed transient hypotension during the infusion at 20 ml/h that ameliorated when the drug was withdrawn. Moreover, 10/16 edematous patients experienced significant and painful digital swelling, unlike patients in the fibrotic group (p < 0.0001); 11/16 patients reported flushing and 7/16 headache, always controlled with dose tapering below 10 ml/h. In the atrophic/fibrotic phase patients (65/81), 10 developed diarrhea and 24 hypotension at infusion rate of 20 ml/h that led to temporary withdrawal of the drug. When ILO was restarted and kept below 10 ml/h, no side effects were experienced. 23/65 patients experienced flushing and 8/65 headache, all controlled with infusion reduction below 10 ml/h. In these patients, adverse events were significantly less frequent than in the edematous group (p = 0.023 and p = 0.008, respectively). Our data suggest that calcium channel blockers should be transitorily stopped while using ILO and that a pre-treatment approach might reduce or control adverse events. In patients with digital edema, ILO infusion should be carefully employed after the evaluation of patient's drug tolerance.

Pulmonary arterial hypertension and rheumatic diseases--from diagnosis to treatment.

Survival rates in pulmonary arterial hypertension (PAH) associated with rheumatic diseases, in particular connective tissue diseases such as systemic sclerosis, are even lower than in idiopathic PAH. These low survival rates highlight the need for early diagnosis and treatment in these patients. Transthoracic Doppler-echocardiography is most often used for diagnostic screening of patients at risk. Other screening tests are serum pro-brain-natriuretic peptide (pro-BNP) and diffusion capacity for carbon monoxide (DLCO), which appear to be changed early in the course of the PAH associated with connective tissue diseases. The diagnosis needs to be confirmed by right heart catheterization, which is recommended in all patients with suspected PAH. Besides the conventional background therapy, a number of specific therapies have been evaluated in randomized controlled trials in the recent years. These therapies include prostacyclins and prostacyclin analogues, endothelin-receptor antagonists and phosphodiesterase-5 inhibitors. Response to treatment can be measured by exercise capacity (e.g. 6 min walk distance) and pro-BNP, although certain aspects of validation for these outcome measures are lacking in PAH associated with connective tissue diseases.

Etrurians vs Greeks: May ACE I/D polymorphism still be considered as a marker of susceptibility to SSc?

OBJECTIVE: SSc is characterized by immune dysfunction and microvascular involvement. A different genetic background may determine a different polymorphic allele frequency between different populations, and data from literature reported conflicting results about the role of genetic components in predisposing to the disease. We carried out this study in order to compare the ACE I/D polymorphism genotype distribution and alleles frequency in two different populations from the Mediterranean area. METHODS: Forty-eight Italian and 41 Greek SSc patients compared with 112 Italian and 93 Greek controls, have been studied. The ACE I/D polymorphism has been analysed. RESULTS: The genotype distribution and allele frequency were in Hardy-Weinberg equilibrium for Italian and Greek SSc patients and controls. Among the Italian patients a significantly higher ACE D allele frequency than in the controls was found, whereas among the Greeks a higher prevalence was observed in the healthy subjects. A significant difference in ACE D allele frequency between Italian and Greek controls was observed (p = 0.04). ACE D allele was associated to the predisposition to SSc in Italians, but not in Greeks. CONCLUSION: We confirm that Italian SSc patients have a higher ACE D allele frequency that is not present in the Greek patients. Thus, the two populations living in different Mediterranean areas and resulting from the Mediterranean civilization, do not show the same ACE-gene related allele frequencies. Other populations of the Mediterranean area must be investigated by using unlinked genetic markers to verify the homogeneity of the genetic background, and to test for a "true" difference in their ethnic origin.

The fibrinolytic system components are increased in systemic sclerosis and modulated by Alprostadil (alpha1 ciclodestryn).

OBJECTIVES: To evaluate urokinase plasminogen activator (u-PA), urokinase plasminogen activator soluble receptor (su-PAR), plasminogen activator inhibitor 1 (PAI-1) and tissue plasminogen activator (t-PA) plasma levels in SSc patients (pts) versus healthy controls and their modulation by intravenous alphacyclodestrine (Alprostadil). METHODS: Plasma levels of u-PA, su-PAR, PAI-1 and t-PA were measured in 40 SSc (34 lSSc and 6 dSSc) pts and in 30 healthy controls. In SSc, blood was drawn before and after 3 consecutive daily of Alprostadil infusion (60 mg in 250 cc NaCl 0.9%). RESULTS: In SSc su-PAR basal levels were higher than controls (7.48 +/- 2.5 vs 4.69 +/- 0.4 ng/ml; p = 0.001) and were significantly reduced by Alprostadil (5.93 +/- 1.7; p = 0.002), but remain higher than controls (p = 0.03). u-PA basal levels were higher than controls (3.78 +/- 1.5 vs 1.29 +/- 0.3 ng/ml; p < 0.001) and were reduced by Alprostadil (2.39 +/- 1.7; p < 0.001) to control levels. SSc PAI-1 basal levels were lower than controls (31.60 +/- 7.7 vs 48.30 +/- 6.8 ng/ml; p < 0.001) and increased by Alprostadil (34.66 +/- 5.4; p = 0.04), but lower than controls (p < 0.001). SSc t-PA basal levels were higher in respect to controls (1645.81 +/- 792.7 vs 571.95 +/- 75.5 pg/ml; p < 0.0001) and reduced by Alprostadil (1318.06 +/- 603.5; p = 0.04), but still higher than controls (p = 0.001). CONCLUSION: Fibrinolysis were increased in SSc. Infusions of Alprostadil modulate u-PA, su-PAR, PAI-1 and t-PA, restoring near normal levels. In SSc, fibrinolysis system may become a potential target for new therapies.

Blood coagulation, fibrinolysis, and markers of endothelial dysfunction in systemic sclerosis.

OBJECTIVE: To evaluate the coagulative/fibrinolytic cascade and the circulating markers of the endothelial injury in systemic sclerosis (SSc). METHOD: Plasma was obtained from 29 patients with SSc and tested for thrombin-antithrombin (TAT), fragments 1+2 (F1+2), dermatansulphate (DS), thrombomodulin (TM), lipoprotein (a) [Lp(a)], von Willebrand factor (vWF), tissue type plasminogen activator (tPA), plasminogen activator inhibitor (PAI), D-dimers, intercellular adhesion molecole-1 (ICAM-1), vascular cell adhesion molecule (VCAM), and E-selectin. The data were correlated with lung (forced vital capacity, diffusing lung capacity for carbon monoxide, vital capacity) and skin (skin score) involvement. RESULTS: Coagulation was significantly activated (increase in F1+2, P <.001; TAT, P <.01; and Lp(a), P <.05). TM was not significantly different from controls. vWF was significantly increased (P <.01), and its supranormal multimers increased in more than 50% of patients. DS was significantly increased in diffuse cutaneous SSc (P <.01). Fibrinolysis was impaired as shown by reduced D-dimers (P <.01) and decreased levels of PAI (P < 0.01). The markers of endothelial injury were also significantly elevated. DS correlated significantly with forced vital capacity (P <.01) and forced vital capacity ratio (P <.01). CONCLUSION: Injury to the endothelium reduces endothelial function, as suggested by impairment of fibrinolysis and activation of the coagulative pathway. The loss of the balance between fibrinolysis and coagulation contributes to vessel engulfment with fibrin and breakdown of vessel patency. The increase of circulating DS suggests that this factor may be a new marker of endothelial injury.

Are Angiotensin Converting Enzyme and von Willebrand factor circulating levels useful surrogate parameters to monitor disease activity in Kawasaki disease?

To verify if Angiotensin Converting Enzyme (ACE) and von Willebrand factor (vWF) may be used as a laboratory marker for the follow-up of endothelial derangement and therapeutic efficacy in Kawasaki disease (KD), circulating ACE, vWF routine hematological tests and cardiac involvement were assessed in 32 children with established diagnosis of KD before and up to six months after intravenous gamma-globulins (i.v.IG) treatment. I.v.IG treatment normalized progressively all the hematological parameters to levels comparable with healthy controls within 30 days. At baseline, ACE levels resulted significantly lower (1.8 +/- 1.3 pmol/ml/min), and vWF levels significantly increased (210.3 +/- 35.2%) when compared with controls (respectively 7.0 +/- 0.9 pm/ml/min and 99 +/- 17.9%). Seven days after the treatment vWF levels were decreased (188 +/- 18.4%) but still significantly higher than controls, and fully normalized after 15 days (104.8 +/- 14.3%). ACE levels were found progressively increased at 7, 15, and 30 days after the treatment (respectively 2.7 +/- 1.0, 3.7 +/- 0.4, 5.04 +/- 0.9 pm/ml/min) and reached the range of normality only after two months (7.74 +/- 2.46 pm/ml/min). The present study shows that ACE and vWF circulating levels are significantly modified during the acute phase of the disease.

Consensus statement concerning cardiotoxicity occurring during haematopoietic stem cell transplantation in the treatment of autoimmune diseases, with special reference to systemic sclerosis and multiple sclerosis.

Autologous haematopoietic stem cell transplantation is now a feasible and effective treatment for selected patients with severe autoimmune diseases. Worldwide, over 650 patients have been transplanted in the context of phase I and II clinical trials. The results are encouraging enough to begin randomised phase III trials. However, as predicted, significant transplant-related morbidity and mortality have been observed. This is primarily due to complications related to either the stage of the disease at transplant or due to infections. The number of deaths related to cardiac toxicity is low. However, caution is required when cyclophosphamide or anthracyclines such as mitoxantrone are used in patients with a possible underlying heart damage, for example, systemic sclerosis patients. In November 2002, a meeting was held in Florence, bringing together a number of experts in various fields, including rheumatology, cardiology, neurology, pharmacology and transplantation medicine. The object of the meeting was to analyse existing data, both published or available, in the European Group for Blood and Marrow Transplantation autoimmune disease database, and to propose a safe approach to such patients. A full cardiological assessment before and during the transplant emerged as the major recommendation.

The nervous system in systemic sclerosis (scleroderma). Clinical features and pathogenetic mechanisms.

The involvement of the nervous system in SSc is well recognized today. Different pathogenetic mechanisms are suggested that may alternatively explain the multiform appearance of the clinical spectrum (mononeuritis, mononeuritis multiplex, carpal tunnel syndrome, and so forth). It is now clear that the ANS is the earliest structure targeted by the disease in the gastrointestinal tract. The importance of this observation has not yet been adequately interpreted but may, together with the increasing evidence of the nervous system involvement in SSc, become a leading factor in understanding of the importance of the nervous system in the onset, development, and maintenance of the disease.

Emerging potentials for an antioxidant therapy as a new approach to the treatment of systemic sclerosis.

Oxidative stress, favoring disease progression by a rapid degeneration of endothelial cell function is deeply involved in Systemic Sclerosis (SSc) pathogenesis. Raynaud's phenomenon (RP), present in 90% of patients with SSc, provoking frequent daily episodes of hypoxia-reperfusion injury, produces several episodes of free radicals-mediated endothelial derangement. These events results in a positive feedback effect of luminal narrowing and ischemia and therefore to the birth of a vicious cycle of oxygen free radicals (OFR) generation, leading to endothelial damage, intimal thickening and fibrosis. Thus ischemia and reperfusion are two criticals events that may induce oxidative stress and inactivation of antioxidant enzymes. In RP and SSc, a reduced concentration of ascorbic acid, alpha-tocopherol and beta-carotene as well as low values of Selenium have been reported. This antioxidative potential deficiency increases the propensity to oxidative stress. favoring the development of injury mediated by OFR. We reviewed several antioxidant compounds, aiming at their capacity of reverting endothelial dysfunction and damage, scavenging lipid peroxidation and reducing multiple episodes of hypoxia-reperfusion injury. In order to interrupt SSc vicious cycle, we propose a main strategy for SSc treatment by a supplementation of antioxidants and different kind of drugs with antioxidant property, such as Lazaroids, Resveratrol, Melatonin and Probucol.

Synoviocytes from osteoarthritis and rheumatoid arthritis produce plasminogen activators and plasminogen activator inhibitor-1 and display u-PA receptors on their surface.

The production of plasminogen activators and their inhibitors was studied in vitro in osteoarthritic (OA) and rheumatoid arthritic (RA) synovial fibroblasts (SF), obtained from RA and OA patients undergoing joint surgery. Subcultured SF were cultivated for 2, 4, 6, 8, 10 and 13 days and the medium assayed for the presence of both plasminogen activators (PAs) and plasminogen activator inhibitor-1 (PAI-1). The presence of urokinase-Plasminogen Activator (u-PA) receptors (u-PAR) on the surface of synovial cells was investigated by radio-ligand binding assay and cross-linking and by transmission electron microscopy (TEM) of a gold-u-PA complex. Our results showed a low production of tissue-type-Plasminogen Activator (t-PA) in both OA and RA SF, but relatively high levels of u-PA, until confluence, both in OA and in RA. SF were also able to produce plasminogen activator inhibitor in large amounts, in particular in RA since the very beginning of the culture. Receptors for u-PA were evident on both RA and OA SF. Our data show that SF in vitro produce mainly u-PA, the most important plasminogen activator involved in tissue modifications. The demonstration of u-PA receptors on the surface of OA and RA SF represents a step forward in the understanding of the possible role of fibrinolytic and tissue destructive proteinase cascade in joint inflammation.

The medical and surgical treatment of finger clubbing and hypertrophic osteoarthropathy. A blind study with colchicine and a surgical approach to finger clubbing reduction.

In fourteen patients affected with pachydermoperiostosis (PDP), or primary hypertrophic osteoarthropathy, the efficacy of colchicine (0.5 mg day for one month) versus placebo on the main clinical features of the disease (finger clubbing, arthritis and pachydermia) was evaluated. In addition, in one patient the usefulness of surgical reduction of clubbed fingertips was investigated. Colchicine did not demonstrate any appreciable effect on finger clubbing (expressed in degrees) or pachydermia, while an effect on arthralgia (as evaluated by the Ritchie Index and Pain Scale) was observed. The surgical treatment of clubbed fingertips failed to show a satisfactory and stable reduction of the fingertips; two months after surgery the nail matrix apparently produced new tissue, once again enlarging and deforming the finger. These results suggest that low dose colchicine cannot be considered the drug of first choice for the treatment of PDP, while higher dosages, although effective, are not tolerated because of the severe side effects. An effective medical and surgical treatment for PDP will be found only when the pathogenetic mechanisms of the disease are clarified.

Bcl-2, p53 and c-myc expression in juvenile dermatomyositis.

OBJECTIVE: To investigate p53, bcl-2 and c-myc expression in muscle biopsies from children affected with juvenile dermatomyositis (JDM) and to verify a possible dysregulation of programmed cell death in this autoimmune disease. METHODS: Ten muscle biopsies of children affected with JDM were formalin fixed and paraffin embedded. After haematoxylin and eosin staining, immunohistochemistry was performed employing monoclonal antibodies, anti-p53, anti-bcl-2 and anti-myc. Two normal muscle biopsies were studied as controls. RESULTS: In the biopsies of JDM, two different patterns of myofibers damage were observed: the first, with zones characterised by necrosis; and the second, with zones where an apoptotic process was dominant. Immunoreactivity for bcl-2 was positive in 8 out of 10 biopsies. P53 and c-myc expression were not present in any case. No relationship between the degree of bcl-2 immunostaining and the disease course or outcome was observed. CONCLUSIONS: The over-expression of bcl-2 protein in JDM may suggest a dysregulation of apoptosis in myofibers. Further studies are required in order to better understand the role of our data in the pathogenetic pathways of the disease.

Effect of melatonin on normal and sclerodermic skin fibroblast proliferation.

OBJECTIVE: We studied the effect of melatonin (MLT) (N-acetyl 5-methoxytryptamine) on the growth rate of normal skin fibroblasts and of fibroblasts from involved and apparently uninvolved skin of patients affected by systemic sclerosis (SSc). METHODS: The growth rate was evaluated on the basis of growth curves and a 3H-thymidine incorporation assay. RESULTS: Our results demonstrate that a dose of 200 micrograms/ml of MLT inhibits (> 80%) both control and SSc fibroblasts. Inhibition was dose-dependent and was greater than 70% for MLT concentrations of 100 micrograms/ml, 200 micrograms/ml and 400 micrograms/ml. 3H-thymidine incorporation was correlated with the effect on the growth curves (81% at 200 micrograms/ml of MLT). In contrast, at a low dosage of 6 micrograms/ml, MLT exerted a stimulatory effect on cell proliferation in all the cell lines analyzed. Cell viability was not affected by MLT at any of the concentrations tested. A recovery study indicated that replacement of MLT-containing medium with MLT-free medium resulted in a re-establishment of cell growth. CONCLUSIONS: These results suggest that MLT, at higher dosages, is a potent inhibitor of the proliferation of fibroblasts derived from the skin of healthy and SSc patients.

Evidence for hyaluronan production in the air pouch model in rats.

OBJECTIVE: The aim of our work was to investigate the presence of hyaluronan (HA) in the rat air pouch and its behaviour in response to inflammatory stimuli. METHODS: HA levels (by a microplate assay) and the leucocyte count were determined in the fluid obtained from air pouches in which acute or subacute inflammation had been induced by the injection of monosodium urate crystals (MSU) or high density polyethylene (HDPE) debris respectively and in relative controls. RESULTS: In control pouches of both groups, remarkable levels of HA were found; these levels were higher in the very first hours (2475 and 1850 micrograms/l at 6 hrs) and then gradually decreased. In pouches injected with MSU, HA moderately increased (p < 0.001) after 6 hrs, reached a peak after 12 hrs (p < 0.001) and began to taper at 24 hrs (p < 0.001). The leucocyte count was also increased at 6 hrs (p < 0.001), became higher at 12 hrs (p < 0.001) and tapered at 24 hrs (p < 0.001). In the HDPE pouches, HA levels were significantly reduced with respect to controls after 6 hours (p < 0.001), increasing later (p < 0.001) to reach a peak at 24 hrs (p < 0.001), and returning to the original levels, or even below, in the following 72 hours. CONCLUSIONS: These data confirm that the pouch lining produces fair amounts of HA and provide evidence that, in this system, HA levels seem to be influenced by the degree of inflammation even if with variable behaviour in relation to the different characteristics and phases of phlogosis. The present data suggest that the air pouch is a useful experimental model for studies on HA metabolism in either acute or chronic inflammation.

Peripheral nervous system involvement in systemic sclerosis: the median nerve as target structure.

OBJECTIVES: To investigate the frequency and the main electrophysiological characteristics of the canalicolar passage nerve involvement in patients with systemic sclerosis (SSc). METHODS: Thirty-two SSc patients were enrolled in the study, classified according to the type (diffuse or limited) and the duration (> / < 5 years) of the disease. Sensory-motor nerve conduction studies (NCS) of the upper and lower limbs, in particular at the critical canalicolar points, were conducted by recording the Compound Muscular Action Potential (CMAP) and the Sensory Action Potential (sNAP). The following parameters were evaluated: Motor Nerve Conduction Velocity (MNCV) and Sensory Nerve Conduction Velocity; distal and proximal latency of the CMAP and the onset and peak latency of the sNAP; peak-peak amplitude and negative-peak area of the CMAP and sNAP; and the Terminal Latency Index (TLI) (Terminal Distance/MCNV x Distal latency). RESULTS: Four (12.5%) patients had a distal neuropathy of the upper limbs (one with monolateral and two with bilateral involvement of the median nerve and one bilateral involvement of the ulnar nerve). Fourteen (43.7%) patients showed a decrement of the median nerve TLI and seven (21.8%) of either the median or the ulnar nerve (Table I). Motor and sensitive conduction velocity and latency studies did not show a statistical difference between SSc patients and controls. The amplitude and area of the CMAP (distal and proximal), sNAP and of the median nerve TLI were significantly decreased in patients with respect to controls. CONCLUSION: Distal mononeuropathy of the median nerve was the most frequent result in our patients. The involvement of the peripheral nervous system seems to be strictly topographical, following the modifications of the tissues and vascular tone (Raynaud's phenomenon) at the upper acral level. The neurophysiological alterations detected in our study at the wrist level may not be linked merely to a compressive event but also to microvascular involvement. Nerve involvement closely connected with the pathogenesis and distribution of SSc should be considered when peripheral nervous system involvement is the initial symptom of the disease.

Anti-endothelial cell antibodies in systemic sclerosis: significant association with vascular involvement and alveolo-capillary impairment.

OBJECTIVE: To assess the frequency of antiendothelial cell autoantibodies (AECAs) in a group of patients with systemic sclerosis (SSc) and possible associations with clinical and serologic features of the disease. METHODS: Sera from 50 patients with SSc (38 with the limited and 12 with the diffuse form) were screened for AECA (ELISA). The reference limits were were 56.6% for the IgM isotype and 3.3.5% for the IgG isotype. AECA results were analyzed in relation to lung involvement (chest x-ray, high resolution computed tomography (HRCT), ventilation scintiscan with radioaereosol (DTPA), pulmonary pressure (echodoppler technique): heart involvement (EKG, 24 hr ambulatory EKG, echocardiography), cutaneous involvement (skin score), capillaroscopic characteristics and digital ulcers. AECA were also correlated with the erythrocyte sedimentation rate (ESR), anticentromere (ACA) and antitopoisomerase I (ATA) autoantibodies, and angiotensin converting enzyme plasma levels (ACE). RESULTS: The AECA IgG prevalence was 40% (22/50) for the SSc group as a whole, without significant differences between subsets. A significant negative correlation was shown between the AECA and ACE plasma levels in both subsets. In the diffuse form, a significant positive correlation was found between AECA and ESR and significant associations were found between AECA and the parameters reflecting alveolo-capillary involvement (DLco, DTPA), the pulmonary artery pressures, digital ulcers and capillaroscopic abnormalities. No statistically significant correlations were found between AECA and heart involvement, the skin score or pulmonary interstitial fibrosis. CONCLUSIONS: These data suggest that in SSc the anti-endothelial cell antibodies are directly linked to vascular injury and could reflect endothelial damage. Further studies are needed to verify whether AECA might identify a subgroup of patients at higher risk for the development of vascular crises and whether they might therefore be considered a predictor of outcome in SSc patients.

Clinical correlations of plasma angiotensin converting enzyme (ACE) activity in systemic sclerosis: a longitudinal study of plasma ACE level, endothelial injury and lung involvement.

Lung involvement was studied by perfusion scan, ventilation scan, pulmonary clearance rate of 99mTc DTPA and pulmonary function tests in 20 patients with systemic sclerosis (SSc). Decreased plasma angiotensin converting enzyme (ACE) activity and increased levels of von Willebrand Factor Antigen (vWF:Ag) were found in all patients with SSc. The relationship between ACE levels and lung involvement was not statistically significant, however levels of vWF:Ag correlated with parameters of lung vascular alterations. An inverse relationship between the reduced ACE levels and ESR was found. It is likely that ACE levels reflect the inflammatory aspect of the disease. Further studies of ACE synthesis, release and inhibition are needed to determine the mechanism of the observed decreased activity in SSc.