[Systemic sclerosis. Current classification and diagnosis of organ involvement]

Systemic sclerosis (SSc) is a rare, chronic inflammatory autoimmune disease with unknown etiology, which leads to deposition of collagen and extracellular matrix proteins in the skin and affected internal organs. The diagnosis of SSc is based on clinical, serological, and paraclinical examinations. In 2013 new criteria for the classification of systemic sclerosis, which also take early forms of SSc into consideration, were developed. A complete clinical and paraclinical examination is important for the oligosymptomatic early stages and the subsequent disease course of SSc in order to diagnose and timely treat a developing organ involvement.

[Digital ulcers in systemic scleroderma]

Digital ulcers (DU's) are one of the main symptoms of systemic scleroderma and occur in approximately 60% of all scleroderma patients. Due to possible complications such as infections, gangrene or amputation, they require regular medical attention and a good wound treatment by doctors and nursing staff. A definition of DU's has not yet been established. In 2009 the European League Against Rheumatism (EULAR) published guidelines for the treatment of DU's. An improvement of the healing of active ulcers has been described with Iloprost. Bosentan significantly reduced the frequency of occurrence of new DU's. In some small studies PDE-5 inhibitors appear helpful. Further studies with other therapeutic approaches will follow in the next few years.

[Differential diagnoses of Raynaud's phenomenon]

Raynaud's phenomenon (RP) is characterized by repeated vasospastic attacks of the distal extremities induced by cold, humidity, vibrations or emotional stress. It typically presents a triphasic colour change from white (palor; vasoconstriction) to blue (cyanosis) and red (reactive hyperaemia). The symptoms are based on a primary RP in 90 %. Secondary RP is a symptom of an underlying disease. RP has to be distinguished from other colour changes of the distal extremities like acrocyanosis, erythromelalgia, perniosis and Chilblain-Lupus. Patients history, clinical examination, ANA, ESR/CRP and nailfold capillaroscopy are essential for the early diagnosis of an underlying disease. The initiation of angiologic tests is important in patients with digital ulcers, necrosis or gangrene. Important differential diagnoses in secondary RP are autoimmune rheumatic diseases like systemic sclerosis and systemic lupus erythematodes as well as vascular diseases like arterial occlusions and compression syndromes or concomitant medication (i. e. beta-blocker).

[The German network for systemic sclerosis (DNSS): current data on diagnostics and therapy]

An essential prerequisite for progress in understanding the pathophysiology and the clinical treatment of rare diseases is the national cooperation of specialized centers. The German network for systemic sclerosis (DNSS) is such an interdisciplinary union of hospitals and research centers with a special interest in systemic sclerosis (SSc). A core activity is the patient register of the DNSS which includes over 3,100 patients. It is one of largest national registers of SSc patients worldwide and comprises prospective data on diagnostics as well as primarily therapy of the patients. The register has now proven to be an extremely successful basis for clinical research and basic studies within the framework of international cooperation. The most important results of the cooperation and the register will be presented in this article.

Randomized, double-blind, placebo-controlled study of safety and efficacy of miltefosine in antihistamine-resistant chronic spontaneous urticaria

BACKGROUND

Chronic spontaneous urticaria (CSU), a mast cell-driven condition, is debilitating, common, and hard to treat. Miltefosine, a lipid raft modulator, can inhibit mast cell responses in vivo.

OBJECTIVE

To study the safety and efficacy of systemic miltefosine treatment in CSU patients resistant to standard-dosed antihistamines.

METHODS

In this investigator-initiated multicentre, randomized, double-blind, placebo-controlled study, CSU patients were treated for 4 weeks with daily doses of up to 150-mg miltefosine (n = 47) or placebo (n = 26). Disease activity was assessed using the urticaria activity score. Safety and tolerability of miltefosine were also assessed.

RESULTS

After 4 weeks of treatment, Urticaria Activity Score (UAS7) levels were substantially more reduced in miltefosine-treated patients (-6.3 vs. -3.5 in placebo-treated patients; P = 0.05). Also, the number of weals, but not the intensity of pruritus, was significantly reduced in miltefosine-treated patients vs. placebo-treated patients (P = 0.02). In general, adverse events were frequent in both groups (miltefosine: 88%, placebo: 65% of patients) but mostly mild to moderate in severity. We did not observe any serious adverse events.

CONCLUSIONS

The results of this study indicate that miltefosine is an effective and safe treatment option for CSU patients who do not respond to standard-dosed antihistamines.

Evidence that deletion at FCGR3B is a risk factor for systemic sclerosis

There is increasing evidence that gene copy number (CN) variation influences clinical phenotype. The low-affinity Fc receptor 3B (FCGR3B) located in the FCGR gene cluster is a CN polymorphic gene involved in the recruitment of polymorphonuclear neutrophils to sites of inflammation and their activation. Given the genetic overlap between systemic lupus erythematosus and systemic sclerosis (SSc) and the strong evidence for FCGR3B CN in the pathology of SLE, we hypothesised that FCGR3B gene dosage influences susceptibility to SSc. We obtained FCGR3B deletion status in 777 European Caucasian cases and 1000 controls. There was an inverse relationship between FCGR3B CN and disease susceptibility. CN of ≤ 1 was a significant risk factor for SSc (OR=1.55 (1.13-2.14), P=0.007) relative to CN ≥ 2. Although requiring replication, these results suggest that impaired immune complex clearance arising from FCGR3B deficiency contributes to the pathology of SSc, and FCGR3B CN variation is a common risk factor for systemic autoimmunity.

Evidence of the contribution of the X chromosome to systemic sclerosis susceptibility: association with the functional IRAK1 196Phe/532Ser haplotype

OBJECTIVE

Several autoimmune disorders, including systemic sclerosis (SSc), are characterized by a strong sex bias. To date, it is not known whether genes on the sex chromosomes influence SSc susceptibility. Recently, an IRAK1 haplotype that contains the 196Phe functional variant (rs1059702), located on Xq28, was found to confer susceptibility to systemic lupus erythematosus (SLE). This study was undertaken to test for an association between SSc and the IRAK1 SLE risk haplotype.

METHODS

We tested for an association with the IRAK1 SLE risk haplotype in a discovery set of 849 SSc patients and 625 controls. IRAK1 rs1059702 was further genotyped in a replication set, which included Caucasian women from Italy (493 SSc patients and 509 controls) and Germany (466 SSc patients and 1,083 controls).

RESULTS

An association between the IRAK1 haplotype and SSc was detected in the discovery set. In both the discovery and replication sets, the rs1059702 TT genotype was found to be associated with specific SSc subsets, highlighting a potential contribution to disease severity. A meta-analysis provided evidence of an association of both the T allele and TT genotype with the overall disease, with an odds ratio (OR) of 1.20 and 95% confidence interval (95% CI) of 1.06-1.35 for the T allele (P = 0.003) and an OR of 1.49 and 95% CI of 1.06-2.10 for the TT genotype (P = 0.023). However, the most notable associations were observed with the diffuse cutaneous, anti-topoisomerase I antibody positive, and SSc-related fibrosing alveolitis subsets (OR 2.35 [95% CI 1.51-3.66], P = 1.56 × 10(-4), OR 2.84 [95% CI 1.87-4.32], P = 1.07 × 10(-6), and OR 2.09 [95% CI 1.35-3.24], P = 9.05 × 10(-4), respectively).

CONCLUSION

Our study provides the first evidence of an association between IRAK1 and SSc, demonstrating that a sex chromosome gene directly influences SSc susceptibility and its phenotypic heterogeneity.