Limited Exercise Capacity in Patients with Systemic Sclerosis: Identifying Contributing Factors with Cardiopulmonary Exercise Testing

Objective.

Exercise limitation in patients with systemic sclerosis (SSc) is often multifactorial and related to complications such as interstitial lung disease (ILD), pulmonary vasculopathy (PV), left ventricular dysfunction (LVD), and/or peripheral/muscular limitation (PML). We hypothesized that cardiopulmonary exercise testing (CPET) could not only suggest and rank competing etiologies, but also highlight peripheral impairment.

Methods.

Clinical, resting pulmonary function testing, and CPET data from patients with SSc referred for exercise limitation between October 2009 and November 2015 were retrospectively analyzed in this bi-center study. Patients were categorized as having ILD, PV, LVD, and/or PML based on CPET response patterns and the diagnoses were matched with results from the reference investigations. The latter consisted of transthoracic echocardiography, chest computed tomography scan, and right heart catheterization (RHC).

Results.

Twenty-seven patients presented with CPET profiles consistent with ILD (n = 16), PV (n = 15), LVD (n = 5), and PML (n = 19). None of the subjects had a normal CPET profile. There was a statistically significant negative correlation between resting DLCO, on the one hand, and dead space to tidal volume ratio and alveolar–arterial gradient [P(Ai-a)O2] on the other (p < 0.005). CPET identified 90% of patients with a mean pulmonary arterial pressure at rest ≥ 21 mmHg measured by RHC (n = 10). Peak P(Ai-a)O2, taken independently from other variables, was crucial in distinguishing subjects with ILD from those without ILD (p < 0.05).

Conclusion.

CPET is useful for the characterization of multifactorial exercise limitation in patients with SSc and in identifying SSc-related complications such as ILD and PV. This study also identifies PML as an underestimated cause of exercise limitation.

Combined measurement of carbon monoxide and nitric oxide lung transfer does not improve the identification of pulmonary hypertension in systemic sclerosis

Screening is important to determine whether patients with systemic sclerosis (SSc) have pulmonary hypertension because earlier pulmonary hypertension treatment can improve survival in these patients. Although decreased transfer factor of the lung for carbon monoxide (TLCO) is currently considered the best pulmonary function test for screening for pulmonary hypertension in SSc, small series have suggested that partitioning TLCO into membrane conductance (diffusing capacity) for carbon monoxide (DMCO) and alveolar capillary blood volume (VC) through combined measurement of TLCO and transfer factor of the lung for nitric oxide (TLNO) is more effective to identify pulmonary hypertension in SSc patients compared with TLCO alone. Here, the objective was to determine whether combined TLCO–TLNO partitioned with recently refined equations could more accurately detect pulmonary hypertension than TLCO alone in SSc.

For that purpose, 572 unselected consecutive SSc patients were retrospectively recruited in seven French centres.

Pulmonary hypertension was diagnosed with right heart catheterisation in 58 patients. TLCO, TLNO and VC were all lower in SSc patients with pulmonary hypertension than in SSc patients without pulmonary hypertension. The area under the receiver operating characteristic curve for the presence of pulmonary hypertension was equivalent for TLCO (0.82, 95% CI 0.79–0.85) and TLNO (0.80, 95% CI 0.76–0.83), but lower for VC (0.75, 95% CI 0.71–0.78) and DMCO (0.66, 95% CI 0.62–0.70).

Compared with TLCO alone, combined TLCO–TLNO does not add capability to detect pulmonary hypertension in unselected SSc patients.

Pulmonary hypertension in systemic sclerosis: different phenotypes

Pulmonary hypertension (PH) is a frequent and severe complication of systemic sclerosis (SSc). PH in SSc is highly heterogeneous because of the various clinical phenotypes of SSc itself and because the mechanisms of PH can vary from one patient to another. PH in SSc may be due to vasculopathy of the small pulmonary arteries (group 1; pulmonary arterial hypertension), interstitial lung disease (group 3; PH due to lung disease or chronic hypoxia) or myocardial fibrosis leading to left ventricular systolic or diastolic dysfunction (group 2; PH due to chronic left-heart disease). Pulmonary veno-occlusive disease is not uncommon in SSc and may also cause PH in some patients (group 1′). There is a high prevalence of each of these conditions in SSc and, as such, it may be difficult to determine the dominant cause of PH in a particular patient. However, careful phenotyping of PH in SSc is important as the therapy required for each of these underlying conditions is very different. In this review, we will decipher the different phenotypes of SSc-PH.

Pulmonary hypertension in systemic sclerosis is heterogeneous with various possible mechanismshttp://ow.ly/s98X30f0lcu

TAFRO Syndrome in Caucasians: A Case Report and Review of the Literature

Background

TAFRO syndrome has been reported in Japan among human herpesvirus 8 (HHV-8)-negative/idiopathic multicentric Castleman’s disease (iMCD) patients. To date, the majority of iMCD patients with TAFRO syndrome originate from Japan.

Case presentation

Herein, we report a 67-year-old HIV/HHV-8-negative Caucasian iMCD patient diagnosed with TAFRO. He presented with marked systemic inflammation, bicytopenia, terminal renal insufficiency, diffuse lymphadenopathies, and anasarca. Lymph node and bone marrow biopsies revealed atrophic germinal centers variably hyalinized and megakaryocytic hyperplasia with mild myelofibrosis. Several other biopsies performed in kidneys, liver, gastrointestinal tract, prostate, and lungs revealed unspecific chronic inflammation. The patient had a complete response to corticosteroids, tocilizumab, and rituximab. He relapsed twice following discontinuation of rituximab. When reviewing the literature, we found seven other Caucasian cases with TAFRO syndrome. There were no significant differences with those described by the Japanese cohort except for the higher frequency of kidney failure and auto-antibodies in Western patients.

Conclusion

This case illustrates that patients with TAFRO syndrome can develop non-specific inflammation in several tissue sites. Furthermore, this case and our review of the literature demonstrate that TAFRO syndrome can affect Caucasian and Japanese patients highlighting the importance of evaluating for this syndrome independently of ethnic background.

Pulmonary Arterial Hypertension Associated With Systemic Lupus Erythematosus: Results From the French Pulmonary Hypertension Registry

BACKGROUND

Pulmonary arterial hypertension (PAH) is a rare complication of systemic lupus erythematosus (SLE).

METHODS

We identified all patients with SLE and PAH (SLE-PAH) who were enrolled in the French Pulmonary Hypertension Registry with a diagnosis confirmed by right heart catheterization (RHC). A control group of 101 patients with SLE without known PAH was selected from SLE expert centers participating in the Pulmonary Hypertension Registry. Survival was estimated by the Kaplan-Meier method. Hazard ratios associated with potential predictors of death were estimated using Cox proportional hazard models.

RESULTS

Of the 69 patients with SLE-PAH identified in the French Pulmonary Hypertension Registry, 51 were included in the study. They did not differ from the control group regarding age, sex, or duration of SLE at the time of the analysis but had a higher frequency of anti-SSA and anti-SSB antibodies. The delay between SLE diagnosis and PAH diagnosis was 4.9 years (range, 2.8-12.9) years. The 3- and 5-year overall survival rates were 89.4% (95% CI, 76.2%-96.5%) and 83.9% (95% CI, 68.8%-92.1%), respectively. The survival rate was significantly better in patients with anti-U1-RNP antibodies (P = .04).

CONCLUSIONS

Patients with SLE-PAH have an overall 5-year survival rate of 83.9% after the PAH diagnosis. Anti-SSA/SSB antibodies may be a risk factor for PAH, and the presence of anti-U1-RNP antibodies appears to be a protective factor regarding survival.

Misdiagnosis trends in patients with hereditary angioedema from the real-world clinical setting

BACKGROUND

Hereditary angioedema due to C1 inhibitor deficiency (C1-INH-HAE) causes swelling in the skin and upper airways and pain in the abdomen because of mucosal swelling. C1-INH-HAE is frequently misdiagnosed, leading to delays in diagnosis, inadequate treatment, and unnecessary procedures.

OBJECTIVE

To evaluate the history of misdiagnosis in patients participating in the Icatibant Outcome Survey (IOS).

METHODS

The IOS is an observational study in which safety and effectiveness of icatibant have been evaluated since 2009. As part of the IOS, patients record any misdiagnoses received before being diagnosed as having C1-INH-HAE.

RESULTS

In January 2016, a total of 418 of 633 IOS patients with C1-INH-HAE type I or II had provided misdiagnosis data. Of these, 185 of 418 (44.3%) received 1 or more prior misdiagnoses. The most common misdiagnoses were allergic angioedema (103 of 185) and appendicitis (50 of 185). A variety of other misdiagnoses were reported, including a substantial number of gastrointestinal disorders (excluding appendicitis). Misdiagnosis rates were similar between males (41.1%) and females (46.5%) and between C1-INH-HAE type I (43.7%) and type II (51.6%). Patients with family members diagnosed as having C1-INH-HAE were significantly less likely to be misdiagnosed than patients without a family history (140 of 366 [41.7%] vs 38 of 58 [65.5%], respectively; P = .001). Patients with a prior misdiagnosis had longer median delay to C1-INH-HAE diagnosis (13.3 years) than patients without (1.7 years; P < .001).

CONCLUSION

From this large database, approximately 50% of patients with C1-INH-HAE type I or II have previously had their conditions misdiagnosed, most commonly as allergic angioedema or appendicitis. Misdiagnosis results in marked delays in receiving the correct diagnosis, during which time patients cannot access effective, lifesaving treatment.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01034969.

Predictors of lung function test severity and outcome in systemic sclerosis-associated interstitial lung disease

Systemic sclerosis-related interstitial lung disease (SSc-ILD) is the leading cause of death in SSc. In this study, we aimed to describe the baseline severity and evolution of forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO) in patients with SSc-ILD and to assess the baseline clinical, biological and high-resolution CT scan (HRCT) predictors of this evolution. Baseline and serial FVC and DLCO were collected in 75 SSc-ILD patients followed during 6.4±4.2 years (n = 557 individual data). FVC and DLCO evolution was modelled using a linear mixed model with random effect. During follow-up, FVC was stable while DLCO significantly decreased (-1.5±0.3%/year (p<0.0001). Baseline NYHA functional class III/IV, extensive SSc-ILD on HRCT and DLCO<80% were associated with a lower baseline FVC. Absence of digital ulcers extensive SSc-ILD, and FVC<80% and were associated with a lower baseline DLCO. Presence or history of digital ulcers and presence of pulmonary hypertension at baseline or during follow-up were associated with a faster decline of DLCO overtime. Neither age, gender, subtype of SSc nor specificity of autoantibodies were associated with baseline severity or outcome of lung function tests. In this SSc-ILD population, FVC was therefore stable while DLCO significantly declined over time. ILD extension was associated with baseline FVC and DLCO but not with their evolution. Presence or history of digital ulcers and pulmonary hypertension were predictors of a faster decline of DLCO over time.

Hereditary angioedema with normal C1 inhibitor and factor XII mutation: a series of 57 patients from the French National Center of Reference for Angioedema

Hereditary angioedema (HAE) is a rare disease associated with either a quantitative or qualitative deficiency in C1-inhibitor (C1-INH) or normal C1-INH. HAE with normal C1-INH is associated in 20% of cases with mutations in the gene for factor XII (FXII) or FXII-HAE. A recent review described 41 families, including 14 German and 15 Spanish families. We have constructed a register of French patients and their characteristics. A national survey was launched through the French National Center of Reference for Angioedema (CREAK) to study the clinical, biological and therapeutic characteristics of patients with HAE linked to a mutation of FXII gene. Fifty-seven patients were identified from 24 different families. In most cases they were young women (mean age at diagnosis: 31 years, mean age at first symptom: 21 years, female/male ratio: 76%). Twenty-one per cent of the patients experienced angioedema attacks only during pregnancy or when on oestrogen contraception. Sixty-three per cent had attacks at all times, but they were more severe during these same periods. Male carriers of the mutation were more frequently asymptomatic than females (P = 0·003). C1-INH concentrate and icatibant were both effective for treating attacks. The prophylactic use of tranexamic acid led to a 64% decrease in the number of attacks. This is one of the largest series reported of HAE patients with FXII mutation. The therapeutic management appeared to be identical to that of HAE with C1-INH deficiency.

[Usefulness of nuclear medicine in Erdheim-Chester disease: A Lille experience]

INTRODUCTION

Erdheim-Chester disease is a rare form of non-langerhans histiocytosis and its etiology is still not well established. The aims of the study were to assess the value of the bone scintigraphy and the ¹⁸F-FDG PET/CT for the diagnostic and for the latter in the therapeutic evaluation.

METHODS

We retrospectively reviewed 49 patients suspected of Erdheim-Chester disease between 2004 and 2016. Bone scintigraphy was compared with histopathology and PET-CT to conventional morphological examinations and bone scintigraphy. For therapeutic evaluation, thresholds similar to PERCIST 1.0 were used.

RESULTS

Forty-nine bone scintigraphy were evaluated with a sensitivity of 100%, a specificity 97%, a positive predictive value 90% and a negative predictive value of 100%. Eight patients had at least an initial PET-CT. The sensitivity compared to conventional morphological examinations differed from the location but was excellent for orbital, bone and vascular involvements. Specificity was comparable between the different examinations. Six patients treated with interferon^® and three with vemurafenib^® were followed by PET-CT. PET-CT, in agreement to clinicobiological data, identified 4 partial responses and one complete response with interferon^® et two partial responses and one complete response with vemurafenib^®.

CONCLUSION

Our retrospective study suggests that bone scintigraphy and 18F-FDG PET/CT could be useful in the initial assessment of Erdheim-Chester disease but also for the latter in the therapeutic evaluation.

Intravenous immunoglobulins in systemic sclerosis: Data from a French nationwide cohort of 46 patients and review of the literature

BACKGROUND

As intravenous immunoglobulins (IVIG) exhibit immunomodulatory and antifibrotic properties, they may be a relevant treatment for systemic sclerosis (SSc). The objectives of this work were thus to report on the efficacy and safety of IVIG in a population of SSc patients and to review the available literature.

METHODS

46 patients from 19 French centers were retrospectively recruited. They were included if they had a diagnosis of SSc and received at least 1 IVIG infusion at a dosage >1g/kg/cycle. Relevant data collected at IVIG discontinuation were compared to those collected at IVIG initiation. A comprehensive literature review was performed.

RESULTS

We observed a significant improvement of muscle pain (74% vs. 20%, p<0.0001), muscle weakness (45% vs. 21%, p=0.01), joint pain (44% vs. 19%, p=0.02), CK levels (1069±1552UI vs. 288±449UI, p<0.0001) and CRP levels (13.1±17.6mg/L vs. 9.2±16.6mg/L, p=0.001). We also noted a trend for an improvement of gastro-esophageal reflux disease (68% vs. 53%, p=0.06) and bowel symptoms (42% vs. 27%, p=0.06). Skin and cardiorespiratory involvements remained stable. Finally, corticosteroid daily dose was significantly lower by the end of treatment (13.0±11.6mg/day vs. 8.9±10.4mg/day, p=0.01). Only two severe adverse events were reported (one case of deep vein thrombosis and one case of diffuse edematous syndrome).

CONCLUSION

Our work suggests that IVIG are a safe therapeutic option that may be effective in improving musculoskeletal involvement, systemic inflammation, digestive tract symptoms and could be corticosteroid sparing.

B Cell Homeostasis and Functional Properties Are Altered in an Hypochlorous Acid-Induced Murine Model of Systemic Sclerosis

Introduction

During systemic sclerosis (SSc), peripheral B cells display alterations in subset homeostasis and functional properties and are a promising therapeutic target. However, there is only few data regarding whether these anomalies are accurately reproduced in animal models of SSc.

Objective

In this work, we assessed the B cell homeostasis modifications in an experimental model of SSc [hypochlorous acid (HOCl)-induced mouse], both at a phenotypic and functional level, during the course of the disease.

Methods

Balb/c mice underwent daily intradermal injections of HOCl (or phosphate-buffered saline) and were then sacrificed at day 21 (early inflammatory stage) or day 42 (late fibrotic stage). For phenotypic studies, the distribution of the main spleen cell subsets (B cells, T CD4 and CD8 cells, NK cells, macrophages) and splenic B cell subsets (immature, mature naïve, germinal center, antibody-secreting, memory, B1) was assessed by flow cytometry. For functional studies, splenic B cells were immediately MACS-sorted. Production of interleukin (IL)-6, CCL3, IL-10, and transforming growth factor (TGF)-β was assessed ex vivo by RT-PCR and after 48 h of culture by ELISA. Regulatory B cell (Breg) counts were quantified by flow cytometry.

Results

Phenotypic analyses showed an early expansion of transitional B cells, followed by a late expansion of the mature naive subset and decrease in plasmablasts and memory B cells. These anomalies are similar to those encountered in SSc patients. Functional analyses revealed a B-cell overproduction of pro-inflammatory cytokines (IL-6 and CCL3) and an impairment of their anti-inflammatory capacities (decreased production of IL-10 and TGF-β, reduced levels of Bregs) at the early inflammatory stage; and an overproduction of pro-fibrotic cytokines (TGF-β and IL-6) at the late fibrotic stage. These results approximate the anomalies observed in human SSc.

Conclusion

This work reports the existence of anomalies in B cell homeostasis and functional properties in an animal model of SSc that approximate those displayed by SSc patients. These anomalies vary over the course of the disease, which pleads for their participation in inflammatory and fibrotic events. This makes the HOCl mouse a relevant experimental model for the study of B cells, and therefore, B-cell-targeted therapies in SSc.

Hereditary angioedema with normal C1 inhibitor in a French cohort: Clinical characteristics and response to treatment with icatibant

Introduction

The clinical characteristics and icatibant‐treatment outcomes of patients with hereditary angioedema with normal C1 inhibitor (HAE‐nC1 INH) are limited.

Methods

We retrospectively analyzed data from French HAE patients enrolled in the Icatibant Outcome Survey registry (from July 2009 to September 2013) to compare disease characteristics and the effectiveness and safety of acute icatibant‐treated angioedema attacks in patients with HAE‐nC1 INH, HAE with C1 INH deficiency (type I), or dysfunction (type II).

Results

One center in Grenoble contributed 22 patients with HAE‐nC1 INH and a family history of HAE while 15 centers across France contributed 153 patients with HAE type I and seven patients with HAE type II. Patients with HAE‐nC1 INH compared to HAE type I, respectively, were more likely to be female (88.1% vs. 63.4%), older at median age of disease onset (21 years vs. 15 years), and have a greater rate of abdominal (80% vs. 61%) and laryngeal (23% vs. 14%) attacks. Icatibant was effective in both groups though the median time to resolution of attack was significantly longer in the HAE‐nC1 INH group (20.0 h, 37 attacks) versus the HAE type I group (14.0 h, 67 attacks). Icatibant was self‐administered for 96.1% of attacks in patients with HAE‐nC1 INH and 75.8% in patients with HAE type I. No serious adverse side effects related to icatibant were reported.

Conclusions

These data help further define the disease characteristics of HAE‐nC1 INH in the French population and extend the limited data reporting the safe and effective use of icatibant in acute treatment of angioedema in French patients diagnosed with HAE‐nC1 INH.