A Proposal of a New Tool for the Assessment of Damage in Behçet Syndrome Uveitis: Cerrahpasa Ocular Damage Grading System.

INTRODUCTION/OBJECTIVE: There is currently no tool available to assess the severity of damage in uveitis due to Behçet's syndrome (BS). In this preliminary study, we developed a new grading system to evaluate ocular damage and assessed it in a prospective cohort. METHODS: A specialist in BS uveitis (YO) developed a grading system for ocular damage with five grades based on the extent of damage in the posterior segment. YO trained a senior and general ophthalmologist with sample fundus images. BS patients who had undergone color fundus photography during their routine visits in attack-free periods were included in the study. The color fundus photos of this prospective cohort were evaluated blindly by YO and his trainees using the new grading tool. Inter and intra-observer agreement between the graders were assessed by Cohen's kappa analysis. The evaluation of YO was considered as the gold standard. RESULTS: One hundred eighty-five eyes of 108 (29 F/79 M) patients with BS uveitis were graded for damage by two investigators. Their mean age was 38,58 years and their median ocular disease duration was 13 years. The gold standard and the two investigators exhibited substantial concordance with the ocular damage grading system. The inter- and intra-observer agreement were also almost perfect. CONCLUSION: The newly developed ocular damage grading system enables the standardization of damage severity in BS uveitis. It is imperative to conduct internal and external validations across diverse cohorts. Furthermore, future studies should investigate its correlation with other multimodal imaging methods such as fluorescein angiography and optical coherence tomography.

Pulmonary artery involvement due to Behçet's syndrome and Hughes Stovin syndrome: a comparative study.

OBJECTIVES: Hughes-Stovin syndrome (HSS) is a rare inflammatory condition defined as pulmonary artery aneurysms (PAA) associated with deep vein thrombosis. It is similar to vascular involvement of Behçet's syndrome (BS), but differs in the absence of typical skin-mucosal findings. Whether HSS is a distinct entity or a form fruste of BS is debated. We formally compared HSS cases retrieved from the literature to BS patients with PAI followed by a tertiary centre. METHODS: A systemic literature search using 'Hughes Stovin syndrome' as the key word covering the period between 2000 and 2023 revealed 58 (43 M/15 F) case reports (PROSPERO: CRD42023413537). We identified 74 (62M/12 F) BS patients with PAI followed up in a tertiary centre in Turkey from 2000 until 2020. We evaluated two cohorts head-to-head in terms of demographic and clinical features. RESULTS: BS and HSS patients were found to be comparable with regard to several demographic, clinical and histopathological features. However, PAA were significantly more frequent and isolated pulmonary artery thrombosis (PAT) less common in HSS than that found in BS. Moreover, patients with HSS were more likely to be treated with anti-coagulants and vascular or surgical interventions, whereas less likely to receive immunosuppressive treatment. CONCLUSIONS: Our study indicates that HSS is indeed an 'incomplete form of BS'. It can be considered as evidence supporting the notion that the vascular phenotype develops independently from skin-mucosa lesions and uveitis in BS. However, HSS has been described mainly focusing on aneurysms, overlooking the aspect of in-situ thrombosis.

Anakinra in idiopathic recurrent pericarditis: a comprehensive case series and literature review.

OBJECTIVE: Idiopathic recurrent pericarditis (IRP) is defined by recurring episodes of pericardial inflammation without a known cause. This study investigates the safety and efficacy of anakinra, an interleukin­1 inhibitor, as a successful therapy for IRP in cases resistant to conventional treatment. METHODS: A retrospective evaluation of patients treated at our autoinflammatory center between 2011 and 2023 was conducted. Patient files were examined for demographic, clinical, and treatment response data, including nonsteroid anti-inflammatory drugs (NSAIDs), corticosteroids, and colchicine. Monogenic autoinflammatory disease screening was performed for Mediterranean Fever (MEFV), tumor necrosis factor receptor-associated periodic syndrome (TRAPS), mevalonate kinase (MVK), nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3), and nucleotide-binding oligomerization domain-containing protein 2 (NOD2). Patients who experienced multiple episodes of pericarditis were diagnosed with recurrent pericarditis. The study evaluated anakinra treatment in IRP patients unresponsive to conventional therapy. RESULTS: The study included 21 participants, 9 (42.9%) female and 12 (57.1%) male. The average age of the participants was 43.1 ± 16.5 years. The MEFV mutation analysis revealed that 2 (9.5%) had a mutation in exon 10 and 4 (19.0%) had one in exon 2. Out of the 16 cases, 15 successfully discontinued steroid treatment. Four patients (19.0%) experienced injection site reactions. C­reactive protein (CRP) levels were measured at an average of 196 ± 67.8 mg/l before and 2.6 ± 3.15 mg/l after anakinra treatment. CONCLUSION: In conclusion, the study adds to the growing evidence for the efficacy of interleukin-1 inhibitors, such as anakinra, as a promising treatment modality for IRP in cases resistant to conventional treatment.

Mycophenolate mofetil may be an alternative for maintenance therapy of Behçet syndrome uveitis: a single-center retrospective analysis.

Experience with mycophenolate in uveitis due to Behçet syndrome (BS) is limited. Twelve patients with panuveitis or posterior uveitis who were started mycophenolate were included. Data on demographic characteristics, therapies, ocular attacks, and adverse events were extracted from patient charts. Seven patients with BS uveitis were prescribed mycophenolate for remission induction, of which 6 were refractory/intolerant to conventional immunosuppressives. Mycophenolate was combined with anti-TNFs in 3 patients, resulting in no further ocular attacks. Mycophenolate had to be stopped in the fourth patient due to adverse events. The remaining 3 patients continued to have ocular attacks and were switched to other agents without any drop in visual acuity. Among the 5 patients who were prescribed mycophenolate for maintenance, 2 were relapse free, but 3 experienced ocular attacks. One patient had an exacerbation of mucocutaneous lesions, and 2 experienced adverse events. Mycophenolate monotherapy may not be adequate for remission induction of refractory BS uveitis, but it can be a safe and effective alternative when combined with a biologic agent. It may also be an option for maintenance therapy.

Infliximab for vascular involvement in Behçet's syndrome.

OBJECTIVE: Vascular involvement is an important cause of morbidity and mortality in patients with Behçet's syndrome (BS). We aimed to survey the efficacy and safety of infliximab (IFX) in BS patients with vascular involvement followed in a dedicated tertiary center. METHODS: Charts of all BS patients who used IFX for vascular involvement between 2004 and 2022 were reviewed. Primary endpoint was remission at Month 6, defined as lack of new clinical symptoms and findings associated with vascular lesion, lack of worsening of the primary vascular lesion and a new vascular lesion on imaging, and CRP < 10 mg/L. Relapse was defined as development of a new vascular lesion or recurrence of the preexisting vascular lesion. RESULTS: Among the 127 patients (102 men, mean age at IFX initiation: 35.8 ± 9.0 years) treated with IFX, 110 (87%) had received IFX for remission induction and 87 of these (79%) were already on immunosuppressives when the vascular lesion requiring IFX developed. The remission rate was 73% (93/127) at Month 6 and 63% (80/127) at Month 12. Seventeen patients experienced relapses. Remission rates were better among patients with pulmonary artery involvement and venous thrombosis compared to patients with non-pulmonary artery involvement and venous ulcers. Fourteen patients had adverse events leading to IFX discontinuation and 4 had died due to lung adenocarcinoma, sepsis, and pulmonary hypertension-related right heart failure due to pulmonary artery thrombosis (n = 2). CONCLUSION: Infliximab seems to be effective in majority of BS patients with vascular involvement, even in those who are refractory to immunosuppressives and glucocorticoids.

Increased arterial stiffness and accelerated atherosclerosis in Takayasu arteritis.

INTRODUCTION: Cardiovascular diseases are the leading causes of morbidity and mortality in patients with Takayasu arteritis (TAK). Arterial stiffness and accelerated atherosclerosis have been reported in TAK, however, morphological changes in the arterial wall have not been adequately addressed. Shear wave elastography (SWE) is a new, non-invasive, direct and quantitative method of ultrasonography (US) that evaluates elasticity of biological tissues. METHODS: A total of 50 patients with TAK (44F/6 M; mean age: 39.8 ± 8.2 years), 43 with systemic lupus erythematosus (SLE) (38F/5 M; 38.0 ± 7.9 years) and 57 healthy controls (HCs) (50F/7M: 39.5 ± 7.1 years) were studied using carotid B mode US and SWE. Carotid artery intima-media thickness (CCA IMT) and SWE were measured and the atherosclerotic plaques were recorded. Clinical characteristics and cardiovascular risk factors were determined. Intra and inter observer reproducibility was assessed and found good agreement. RESULTS: The mean IMT in the right and left carotid arteries was significantly higher only among patients with TAK when compared to SLE and HCs. Carotid artery plaques were significantly increased only in patients with TAK. On the other hand, the mean SWE value was significantly increased among both TAK and SLE patients when compared to HCs, whereas patients with TAK had the highest value. These were also true after adjustments were made for atherosclerotic risk factors and after all those with atherosclerotic plaques were excluded from the analysis. TAK itself, diastolic blood pressure levels and IMT were independently associated with SWE. CONCLUSIONS: Markedly increased CCA IMT and SWE values appear to be uniquely associated with TAK, suggesting that they could be used as diagnostic tools. Arterial stiffness occurs independently from atherosclerosis and is associated with arterial thickening. Further studies should investigate whether CCA SWE values could predict cardiovascular morbidity and mortality. Strong association with premature atherosclerosis could be also considered as a unique feature of TAK.

Secukinumab-induced IgA vasculitis in a patient with psoriatic arthritis.

OBJECTIVES: Secukinumab (SEC) is an effective and widely used drug in psoriatic disease and axial spondyloarthritis. However, SEC has been found to be associated with inflammatory conditions and vasculitis. These inflammatory adverse effects may complicate the treatment of underlying disease, and clinicians may experience difficulties in recognizing and managing this unusual condition. CASE REPORT: A man aged 56 years with psoriatic disease refractory to conventional disease-modifying antirheumatic drugs was given adalimumab for 6 weeks, then switched to SEC when his psoriatic lesions were exacerbated. After 3 weeks of SEC treatment, he developed systemic features of IgA vasculitis while his skin lesions and arthritis persisted. CONCLUSIONS: Although SEC-related inflammatory adverse events, including vasculitis, are rarely encountered in clinical practice, it is essential to recognize them because they can be mistaken as a component of the underlying inflammatory disease. In addition, the dramatic improvement in many cases after the cessation of SEC underlines the importance of making an accurate diagnosis. Pathogenetically, these adverse events are likely to be paradoxical reactions, except for SEC-induced inflammatory bowel diseases. However, in many aspects, their pathogenesis is controversial and needs clarification.

Post-COVID-19 vaccination inflammatory syndrome: A case report.

A previously healthy 24-year-old male patient was referred to our clinic with bilateral lower extremity pain and dark urine, which were developed 2 weeks after receiving the second dose of the BNT162b2 vaccine against severe acute respiratory coronavirus 2. Laboratory tests indicated rhabdomyolysis. Lower extremity magnetic resonance imaging was compatible with myositis. Myositis-related antibodies were negative. Biopsy taken from gastrocnemius muscle revealed muscle necrosis and striking expression of major histocompatibility complex class I antigen. He was successfully treated, and his complaints were resolved. One week later at follow-up, he reported new-onset exertional dyspnoea with palpitations. ST-segment depressions were spotted on electrocardiography. Troponin T was found elevated as 0.595 ng/ml (normal <0.014 ng/ml). Echocardiography showed a hypokinetic left ventricle with an ejection fraction of 40% and pericardial effusion of 2 mm. An appropriate treatment plan was formulated for the diagnosis of myocarditis, eventually, the patient recovered within 10 days. The BNT162b2 messenger ribonucleic acid (mRNA) vaccine was felt to cause the aforementioned condition since no other aetiology could be identified. Although it is known that BNT162b2 may induce myocarditis, myositis concomitant myocarditis appears to be a very rare adverse effect of this vaccine.

Impact of apremilast on quality of life in Behçet's syndrome: analysis of the phase 3 RELIEF study.

OBJECTIVE: To assess apremilast's impact on patient quality of life (QoL) in active Behçet's syndrome and correlations between improvement in patients' QoL and efficacy measures in the phase 3 RELIEF study. METHODS: QoL measures included Behçet's Disease QoL (BDQoL), 36-Item Short-Form Health Survey V.2 (SF-36v2) Physical/Mental Component Summary (PCS/MCS) and eight subscale scores, focusing on Physical Functioning (PF). Pearson's correlation coefficients assessed relationships between efficacy endpoints (oral ulcer count, oral ulcer pain, Behçet's Syndrome Activity Scale (BSAS), Behçet's Disease Current Activity Form (BDCAF)) and QoL endpoints for apremilast at Week 12. RESULTS: Apremilast (n=104) demonstrated significantly greater improvements versus placebo (n=103) in SF-36v2 PCS (3.1 vs 0.9), MCS (4.6 vs ─0.7) and PF (2.9 vs 0.14), respectively (all p<0.05). Mild correlations were observed in improvements of SF-36v2 measures (PCS, MCS, PF) with oral ulcer count (r=-0.11, PCS), and change in oral ulcer pain from baseline (r=-0.28, PCS; r=-0.10, PF) and BSAS (r=-0.38, PCS; r=-0.20, PF; r=-0.16, MCS). Correlations among BDCAF and SF-36v2 components and BDQoL were variable. BDQoL showed mild/moderate correlations with SF-36v2 components (r=-0.18, PCS; r=-0.13, PF; r=-0.45, MCS). CONCLUSIONS: Apremilast was associated with significant improvements in QoL measures of SF-36v2 PCS, MCS and PF and BDQoL in patients with Behçet's syndrome. Correlations of improvement among QoL endpoints support the beneficial clinical effects of apremilast in Behçet's syndrome. TRIAL REGISTRATION NUMBER: NCT02307513.

Frequency of AA amyloidosis has decreased in Behçet's syndrome: a retrospective study with long-term follow-up and a systematic review.

OBJECTIVE: A decline in the frequency of AA amyloidosis secondary to RA and infectious diseases has been reported. We aimed to determine the change in the frequency of AA amyloidosis in our Behçet's syndrome (BS) patients and to summarize the clinical characteristics of and outcomes for our patients, and also those identified by a systematic review. METHODS: We identified patients with amyloidosis in our BS cohort (as well as their clinical and laboratory features, treatment, and outcome) through a chart review. The primary end points were end-stage renal disease and death. The prevalence of AA amyloidosis was estimated separately for patients registered during 1976-2000 and those registered during 2001-2017, in order to determine whether there was any change in the frequency. We searched PubMed and EMBASE for reports on BS patients with AA amyloidosis. Risk of bias was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool. RESULTS: The prevalence of AA amyloidosis was 0.62% (24/3820) in the earlier cohort and declined to 0.054% (3/5590) in the recent cohort. The systematic review revealed 82 cases in 42 publications. The main features of patients were male predominance and a high frequency of vascular involvement. One-third of patients died within 6 months after diagnosis of amyloidosis. CONCLUSION: The frequency of AA amyloidosis has decreased in patients with BS, which is similar to the decrease observed for AA amyloidosis due to other inflammatory and infectious causes. However, AA amyloidosis is a rare, but potentially fatal complication of BS.

Emergence of new manifestations during infliximab treatment in Behçet's syndrome.

OBJECTIVES: Infliximab (IFX) is increasingly being used for the treatment of severe manifestations of Behçet's syndrome (BS). However, emergence of new manifestations has also been occasionally reported during IFX treatment. We aimed to assess the frequency of new manifestations in our BS patients treated with IFX. METHODS: A chart review was conducted to identify all BS patients treated with IFX in our clinic between 2004 and 2020. Demographic data, indications for IFX initiation, concomitant treatments and outcomes were recorded. A new manifestation was defined as the emergence of a new organ involvement or mucocutaneous manifestation developing for the first time during IFX treatment or within 12 weeks after the last infusion of IFX. RESULTS: Among our 282 patients who used IFX, 19 (7%) patients had developed a total of 23 new manifestations during a mean follow-up of 20.0 (15.3) months. Patients with vascular involvement were more likely to develop a new manifestation (12/19, 63%). Initial manifestations that required IFX were in remission at the time of new manifestation in 14/19 patients. IFX treatment was intensified (n = 6) and/or glucocorticoids, immunosuppressives or colchicine was added to IFX (n = 21). IFX was switched to another agent for the remaining manifestations (n = 8). These treatment modifications led to remission in 17/19 patients. CONCLUSION: New manifestations developed during IFX treatment in 7% of our patients with BS. They could be managed by intensifying IFX treatment or adding other agents in the majority of these manifestations.

Screening for latent tuberculosis before starting TNF-alpha inhibitors in a population with high BCG vaccination rates.

It is assumed that in candidates for TNF-alpha inhibitor (TNFi) treatment, tuberculin skin test (TST) may be unreliable, since BCG vaccination causes false positive and drugs cause false negative results, favoring the use of Quantiferon or T-spot assays. However, these tests may not be readily available in all parts of the world. We aimed to determine the reliability of TST with respect to BCG vaccination and drugs in candidates for TNFi treatment, and how isoniazid is tolerated, assuming that the use of TST would result in increased isoniazid use. We included 1031 adult patients who were prescribed a TNFi for the first time. We analysed the association of BCG and drugs with TST and Quantiferon results, the determinants of a positive TST, and evaluated the tolerability of isoniazid. BCG vaccination and male sex were associated with positive TST (OR 3.56, 95% CI 1.98-6.41 and OR 2.54, 95% CI 1.75-3.68, respectively), while prednisolone and azathioprine were associated with negative TST (OR 0.63, 95% CI 0.43-0.91 and OR 0.40, 95% CI 0.11-0.76). Isoniazid was prescribed to 684 (66.3%) patients and had to be discontinued in 12.2% of these before 9 months, most commonly due to hepatotoxicity (44%). One patient developed tuberculosis despite isoniazid use. BCG vaccination may be associated with false positive TST, despite a long time since vaccination in candidates for TNFi treatment. Prednisolone and azathioprine use were associated with negative TST. Despite the high frequency of isoniazid use associated with using TST instead of QTF, isoniazid was generally well tolerated.

The incidence, clinical characteristics, and outcome of COVID-19 in a prospectively followed cohort of patients with Behçet's syndrome.

Initial case series of small number of patients at the beginning of the pandemic reported a rather guarded prognosis for Behçet's syndrome (BS) patients infected with SARS-CoV-2. In this prospective study, we describe the incidence, clinical characteristics, disease course, management, and outcome in a large cohort of BS patients with laboratory-confirmed infection of SARS-CoV-2. We defined a cohort of 1047 registered BS patients who were aged between 16 and 60 years and seen routinely before the pandemic at the multidisciplinary outpatient clinic. We followed prospectively this cohort from beginning of April 2020 until the end of April 2021. During 13 months of follow-up, of the 1047 (599 M/448 F) patients, 592 (56.5%) were tested for SARS-CoV-2 PCR at least once and 215 (20.5%; 95% CI 0.18-0.23) were tested positive. We observed 2 peaks which took place in December 2020 and April 2021. Of the 215 PCR positive patients, complete information was available in 214. Of these 214, 14 (6.5%) were asymptomatic for COVID-19. In the remaining, the most common symptoms were anosmia, fatigue, fever, arthralgia, and headache. A total of 40 (18.7%) had lung involvement, 25 (11.7%) were hospitalized, 1 was admitted to the intensive care unit while none died. Favipiravir was the most prescribed drug (74.3%), followed by colchicine (40.2%), and hydroxychloroquine (20.1%) in the treatment of COVID-19. After COVID-19, 5 patients (2.3%) were given supplemental O2 and 31 (14.5%) antiaggregant or anticoagulants. During COVID-19, of the 214 PCR positive patients, 116 (54.2%) decreased the dose of their immunosuppressives or stopped taking completely; 36 (16.8%) experienced a BS flare which was mostly oral ulcers (10.3%). None of the patients reported a thrombotic event. A total of 93 (43.5%) patients reported BS flares after a median 45 days of COVID-19 infection and this was found to be significantly associated with immunosuppressive drug discontinuation. Multiple regression analysis adjusted for age and gender indicated that smoking and using interferon-alpha decreased the likelihood of getting COVID-19. The incidence and severity of COVID-19 did not differ between those who were using colchicine or not. The cumulative incidence of COVID-19 in this prospectively followed cohort of BS patients was almost two folds of that estimated for the general population living in Istanbul, Turkey, however, the clinical outcome of COVID-19 was not severe and there was no mortality. The protective effect of smoking and interferon deserves further investigation. On the other hand, colchicine did not have any positive or negative effect against COVID-19. Significant number of patients flared after COVID-19, however, this was significantly associated with immunosuppressive discontinuation during the infection. Contrary to our previous observations, COVID-19 did not seem to exacerbate thrombotic events during or after the infection.

Apremilast for oral ulcers associated with active Behçet's syndrome over 68 weeks: long-term results from a phase 3 randomised clinical trial.

OBJECTIVES: This study assessed the efficacy and safety of apremilast for the oral ulcers associated with Behçet's syndrome (BS) up to 64 weeks. METHODS: The phase 3, double-blind, placebo-controlled RELIEF study randomised adult patients with active BS to placebo or apremilast 30 mg twice daily for 12 weeks, followed by an extension phase with all patients receiving apremilast through Week 64 and 4-week post-treatment follow-up (upon treatment discontinuation). The primary endpoint was area under the curve for the number of oral ulcers over 12 weeks (AUCWk0-12), reflecting the number of oral ulcers over time and accounting for their recurring-remitting course. Oral ulcer number, complete and partial responses, pain and disease activity and quality of life (QoL) were also assessed throughout the study. RESULTS: A total of 207 participants were randomised and received at least one dose of study medication; 178 entered the extension phase and 143 completed Week 64. AUCWk0-12 was significantly lower with apremilast versus placebo (p<0.0001), and oral ulcers number, pain, complete/partial responses, disease activity and QoL with apremilast versus placebo showed improvements at Week 12, which were maintained through Week 64. The most common adverse events were diarrhoea, nausea, headache and upper respiratory tract infection; no new safety concerns were observed with longer-term apremilast exposure. CONCLUSIONS: In patients with oral ulcers associated with BS, apremilast was efficacious and benefits were sustained up to 64 weeks with continued treatment. Apremilast was well tolerated, and safety was consistent with its known safety profile.

Clinical course of acute deep vein thrombosis of the legs in Behçet's syndrome.

OBJECTIVES: Lower extremity deep vein thrombosis (LEDVT) is a serious complication of Behçet's syndrome. Management constitutes mainly of administration of immunosuppressives, but the predictors of relapse and the optimal choice of immunosuppressives remain unclear. In this prospective study, we aimed to detect the risk and predictors of relapse and treatment response to different modalities. METHODS: All Behçet's syndrome patients who presented with a first episode of acute LEDVT between 2010 and 2014 were prospectively followed with a standard protocol. Acute LEDVT was confirmed by Doppler ultrasonography. Serial planned Doppler ultrasonography assessments were performed during follow-up and additionally repeated in case of clinical suspicion. Recanalization rate was assessed at each visit. Our first-line treatment strategy consisted of AZA and CSs. IFN-alpha was used in patients who were refractory to or could not tolerate AZA or had concomitant eye involvement requiring further treatment. RESULTS: Thirty-three patients with LEDVT (26 M/7 F) were prospectively followed for 40.7 ± 13.4 months. Among the 33 patients, 23 relapses were observed in 15 patients. Relapse rates were 29%, 37% and 45% at 6, 12 and 24 months, respectively. Among the possible predictors of relapse, poor recanalization was the only significant factor [hazard ratio 4.34 (95% CI 1.96, 10.0)]. Overall 29 patients were treated with AZA and 17 with IFN-alpha. The relapse rate was lower and recanalization rate was higher with IFN-alpha compared with AZA (12% vs 45% and 86% vs 45%). CONCLUSION: The relapse rate for LEDVT in Behçet's syndrome is high despite AZA treatment. IFN-alpha seems to be a promising agent for preventing LEDVT relapses and achieving good recanalization.

Long term follow-up of Behçet's syndrome patients treated with cyclophosphamide.

OBJECTIVES: CYC remains an important treatment option for Behçet's syndrome (BS) patients with life-threatening manifestations. However, adverse events may occur with CYC and this has led to increased use of biologic agents in other vasculitides. We investigated short and long term adverse events associated with CYC use in BS patients. METHODS: We conducted a retrospective chart review of all BS patients treated with CYC between 1972 and 2006. Patients were called in and a standard form was used for collecting demographic characteristics, indication for CYC, its cumulative dose and short term adverse events, defined as those causing discontinuation of CYC, hospitalization and/or death, long term adverse events, including infertility and malignancy, and outcome. RESULTS: Of 5790 BS patients, 198 (3.4%) had used at least one dose of CYC. Main indications were vascular or neurological involvement. After a median follow-up of 17 years, 52 (26%) patients had died, 113 (57%) could be contacted, and 33 (17%) were lost to follow-up. Vascular involvement was the leading cause of death (n = 27). Seventeen (9%) patients experienced short term adverse events with haemorrhagic cystitis being the most common. After a median follow-up of 25 years (interquartile range: 15-26 years), 17 malignancies occurred in 15 (8%) patients. Infertility was experienced by 26 (30%) patients. CONCLUSION: Long term adverse events such as malignancy and infertility were major problems in our BS patients treated with CYC. These results underline the need for safer treatment modalities that are at least as effective as CYC.