Two distinct patterns of ankylosing spondylitis in Moroccan patients

A cluster analysis of patients with axial spondyloarthritis using tumour necrosis factor alpha inhibitors based on clinical characteristics

Background

This study aimed to classify the distinct group of patients with axial spondyloarthritis (SpA) on tumour necrosis factor alpha inhibitors (TNFi) according to the baseline characteristics using a clustering algorithm.

Methods

The clinical characteristics and demographic data of patients with axial SpA included in the Korean College of Rheumatology Biologics and Targeted Therapy registry were investigated. The patterns of disease manifestations were examined using divisive hierarchical cluster analysis. After clustering, we compared the clinical characteristics of patients and the drug survival of TNFi between the classified groups.

Results

A total of 1042 patients were analysed. The cluster analysis classified patients into two groups: axial group predominantly showing isolated axial manifestations (n = 828) and extra-axial group more frequently showing extra-axial symptoms (n = 214). Almost all extra-axial symptoms (peripheral arthritis, enthesitis, uveitis, and psoriasis) were more frequently observed in the extra-axial group than in the axial group. Moreover, patients in the extra-axial group had shorter disease duration, later disease onset, and higher disease activity than those in the axial group. The disease activity was comparable between the two groups after 1 year of treatment with TNFi. Interestingly, the extra-axial group had a lower drug survival with TNFi than the axial group (p = 0.001).

Conclusions

Cluster analysis of patients with axial SpA using TNFi classified two distinct clinical phenotypes. These clusters had different TNFi drug survival, clinical characteristics, and disease activity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02647-z.

Worldwide Differences in Clinical Phenotype of Axial Spondyloarthritis

PURPOSE OF REVIEW

This review aims to describe the variations in the clinical presentation of axial spondyloarthritis (axSpA) across the globe.

RECENT FINDINGS

We searched the PubMed database and screened more than 1360 articles; 60 of them were selected based on relevance to the topic being discussed and the goals of the review. Most of the clinical manifestations, including IBP, peripheral arthritis, and extra-articular involvement are seen in different regions of the world, but with appreciable clinical heterogeneity, possibly related to a smaller number of patients from some countries, and global variation in the prevalence of HLA-B27. For example, HLA-B27-positive patients have an earlier age of onset, higher prevalence of acute anterior uveitis, and greater familial occurrence. Peripheral arthritis and enthesitis are most commonly seen among axSpA patients from Latin America and Asia, whereas IBD appears to be slightly more common among Middle Eastern and North African patients. The main weakness encountered while reviewing these data is that some studies were small, and others were cross-sectional and retrospective; hence the inferences may have a selection bias. AxSpA is a very heterogenous disease with varied presentation across the globe, in part related to HLA-B27 positivity. It is imperative to further investigate the key regional differences as they impact timely disease recognition and initiation of early treatment. Therefore, there is a need for a large worldwide systematic study to capture the clinical picture of AxSpA in a more uniform manner.

The Use of Infliximab (Remicade®) for the Treatment of Rheumatic Diseases at a Tertiary Center in Lebanon: A 17-Year Retrospective Chart Review

Objectives:

Infliximab (Remicade®) was the first tumour necrosis factor-α (TNF) inhibitor to receive its initial marketing approval from the US Food and Drug Administration (FDA) for the treatment of Crohn’s disease. Following that, infliximab became approved for several immune-mediated inflammatory diseases. No evidence exists in the Middle East and North Africa region on the experience with infliximab use over an extended period in terms of efficacy and safety.

Methods:

The Rheumatology division at the American University of Beirut Medical Centre (AUBMC), one of the largest tertiary centres in the Middle East and North Africa region, has been using infliximab infusions for the treatment of certain rheumatic diseases for around two decades. By reviewing retrospectively medical charts at AUBMC, we investigate indications, safety and efficacy, rate of withdrawals, rate of switching to another biologic, and financial coverage of the drug to present data for practitioners and patients in the region considering infliximab for treatment of immune-mediated inflammatory diseases.

Results:

A total of 198 patients were identified in the past 17 years to have taken infliximab. The largest proportion of treated patients had RA. Fourteen percent of the total cohort experienced serious adverse events, with 96.4% of those events being mild hypersensitivity reactions. Five patients withdrew the medication because of infectious complications, 4 of which were cases of tuberculosis reactivation. Despite that, around half of the patients were switched to another biologic agent such anti-TNF-α, anti-CD20, and anti-IL-6 due to partial response, and less than half were receiving add-on disease-modifying anti-rheumatic drugs (DMARDs) such as methotrexate, 70% of patients who used infliximab only or were switched achieved complete remission at their last hospital information. Around 98% of infliximab users were financially covered.

Conclusion:

According to our experience, infliximab has made remission and prevention of long-term disability realistic goals of therapy in the Middle East region.

Non-radiographic axial spondyloarthritis in Tunisia: main characteristics and detailed comparison with ankylosing spondylitis

OBJECTIVES

The aim of the present study is to compare the clinical features, disease activity, and physical impairment between non-radiographic axial spondyloarthritis and ankylosing spondylitis in Tunisian patients.

METHODS

This is a retrospective study conducted in a single rheumatology center in Tunisia. Patients with axial spondyloarthritis fulfilling the 2009 ASAS criteria were included. The various spondyloarthritis-related variables were compared between non-radiographic axial spondyloarthritis and ankylosing spondylitis. p Values below 0.05 were considered statistically significant.

RESULTS

Among 200 patients with axial spondyloarthritis, 40 had non-radiographic axial spondyloarthritis and 160 had ankylosing spondylitis. The non-radiographic axial spondyloarthritis patients were more frequently female, were younger, and had shorter disease duration. Patients with non-radiographic axial spondyloarthritis experienced enthesitis more frequently compared with ankylosing spondylitis patients. Psoriasis was more frequent in non-radiographic axial spondyloarthritis group, while inflammatory bowel disease was more frequent in ankylosing spondylitis group. The C-reactive protein level and functional score were significantly higher in patients with ankylosing spondylitis compared with non-radiographic axial spondyloarthritis. Tumor necrosis factor inhibitors were offered significantly more often to the ankylosing spondylitis group. There was no statistically significant difference between the 2 groups in other spondyloarthritis parameters.

CONCLUSION

The non-radiographic axial spondyloarthritis is characterized mainly by a marked female prevalence, a higher enthesitis prevalence, and a better physical function.

KEY POINTS

• Patients with nr-axSpA in Tunisia are more frequently female and have shorter disease duration compared with those with AS. • Peripheral manifestations were similar between nr-axSpA and AS patients except for enthesitis which were more frequent within nr-axSpA patients. • The disease activity is similar between the 2 groups of axSpA but the physical function is better within nr-axSpA patients.

The Prevalence of Non-radiographic Axial Spondyloarthritis Among Patients with Inflammatory Back Pain from Northwest and South Africa: Data from a Noninterventional, Cross-Sectional Study

INTRODUCTION

Information is limited on the prevalence and clinical characteristics of nonradiographic axial spondyloarthritis (nr-axSpA) among patients with inflammatory back pain (IBP) in African countries. A global study estimated the prevalence of nr-axSpA among patients with IBP from 19 countries in Latin America, Europe, Asia, and Africa. This post hoc subset analysis focused on estimating prevalence of nr-axSpA and clinical characteristics among patients with IBP from Northwest Africa (Morocco and Algeria) and South Africa.

METHODS

Patients from Northwest Africa and South Africa diagnosed with nr-axSpA according to protocol completed patient-reported outcome measures to assess disease activity and functional limitations, including Ankylosing Spondylitis Disease Activity Score (ASDAS).

RESULTS

Of the 206 patients with IBP from Africa (n = 168, Northwest Africa and n = 38, South Africa), 33 (16.0%) were diagnosed with nr-axSpA (n = 26, Northwest Africa and n = 7, South Africa), corresponding to prevalence rates of 15.5% and 18.4%, respectively. Disease activity per region, measured as mean ASDAS, was 2.4 ± 1.4 and 2.4 ± 0.9, respectively, based on erythrocyte sedimentation rate and 2.4 ± 1.3 and 2.7 ± 0.7 based on C-reactive protein.

CONCLUSIONS

Although the number of patients available for the analysis was low, it appears that the prevalence of nr-axSpA among patients with IBP is similar between Northwest and South Africa, and the disease burden is substantial. Limited access to magnetic resonance imaging may hinder early detection in these areas, thereby affecting the assessment of prevalence.

FUNDING

Pfizer.

Polymorphisms of HLA-A, -B, -Cw and DRB1 antigens in Moroccan patients with ankylosing spondylitis and a comparison of clinical features with frequencies of HLA-B*27

Ankylosing spondylitis (AS) is very often associated with human leukocyte antigen (HLA), particularly HLA-B*27. However, the strength of this association and clinical features may vary in different ethnic groups. Our study aims to assess the distribution of HLA-A, -B, -Cw and DRB1 alleles in Moroccan patients with AS and to compare the clinical features of AS and the frequencies of HLA-B27 in patients from Morocco with other series. Seventy-five patients diagnosed with AS and assessed for clinical manifestations were selected and compared to 100 healthy controls. HLA class I and II antigens were typed by polymerase chain reaction sequence-specific oligonucleotide. HLA-B27 subtypes were studied by polymerase chain reaction amplification with sequence-specific primers. HLA-B27 was found in 64% of patients. It was positively associated with younger age at disease onset, family history, and uveitis while it had a negative association with late onset. Six B*27 subtypes were identified in the AS group. HLA-B*2705 and B*2702 were the most common observed subtypes. Among other HLA genes, a significant increase in the prevalence of HLA-Cw*02 and HLA-DRB*15 was found in AS patients. HLA-B27 is involved in the predisposition of AS in the Moroccan population. HLA-B*2705 and B*2702 were the predominant subtypes supporting previous reports in Caucasian spondyloarthropathies. Other HLA genes, HLA-Cw*02 and HLA-DRB1*15, seem to confer predisposing effect to the disease. However, the lower frequency of HLA-B27 compared to the literature in our study suggests the existence of different genetic and/or environmental factors in Morocco.

Ultrasound features of shoulder involvement in patients with ankylosing spondylitis: a case-control study

Background

During Ankylosing spondylitis (AS) courses, shoulder involvement is common. However, etiologies of shoulder pain in patients with AS remain to be defined. The aim of this study was to investigate the prevalence of ultrasound (US) abnormalities in shoulders of patients with ankylosing spondylitis (AS), and to determine predictive factors of ultrasound shoulder enthesitis.

Methods

38 patients with AS were included with 38 age and sex-matched healthy controls. All patients fulfilled the modified New York criteria for ankylosing spondylitis. Clinical and demographical data were recorded. US examination of bilateral shoulders was performed by a musculoskeletal sonographer according to a defined protocol that included imaging of the insertions of supraspinatus, subscapularis and infraspinatus tendons, rotator cuff tendons, subacromial-subdeltoid bursa, acromioclavicular joint, and glenohumeral joint.

Results

The mean age of patients and controls was 36 years, each group of patients and controls comprised 22 men (57.9%) and 16 women (42.1%). Disease duration was 9.6 ± 7.2 years. Among 38 patients with AS, 21 had coxitis (55%) and 19 had previous or current shoulder pain (50%). AS shoulders presented significantly more ultrasound enthesitis than controls shoulders (43 shoulders (56.6%) versus 8 shoulders (10.5%) respectively). Involvement of rotator cuff tendons was significantly higher in patients with AS compared with control subjects (16/38 (42.1%) versus 6 (15.2%) respectively). However, involvement of gleno-humeral and acromio-clavicular joints was infrequent in both groups. In patients with AS, we found that the presence of coxitis was the only significant predictive factors of shoulder enthesitis (Odds Ratio (OR) = 9.4; Confidence interval (CI) 95% (1.10; 81.9), p = 0.04).

Conclusions

Ultrasound abnormalities of shoulders are common in patients with AS, and the most frequent abnormalitie was enthesitis, which was associated with the presence of coxitis.

Safety of tumor necrosis factor inhibitors use for rheumatoid arthritis and ankylosing spondylitis in Africa, the Middle East, and Asia: focus on severe infections and tuberculosis

Multiple studies of patients in Western countries with rheumatoid arthritis (RA) and ankylosing spondylitis (AS) have indicated increased risk for active tuberculosis (TB) and other infections among these individuals. It has also been consistently reported that patients receiving tumor necrosis factor (TNF) inhibitors for these conditions have higher rates of active TB and other infections than RA or AS patients not receiving these medications. These issues have been studied less extensively in the Asia and Africa-Middle East regions, and information from these regions is important because of higher rates of TB in the general population. This paper reviews studies of RA and AS patients from Asia, Africa, and the Middle East who received TNF inhibitors. A literature search was conducted using http://www.ncbi.nlm.nih.gov/pubmed to collect and report these data. The years included in the PubMed literature search ranged from January 2000 to October 2011. Additionally, information from the China Hospital Knowledge Database was used to report data from Chinese patients with RA and AS treated with TNF inhibitors. Results from these studies indicate that the risk for active TB and other infections in AS and RA patients from Asia, Africa, and the Middle East are increased in patients receiving TNF inhibitors and that the risk is higher among those treated with monoclonal antibodies versus soluble TNF receptor.

Early diagnosis and treatment of ankylosing spondylitis in Africa and the Middle East

Ankylosing spondylitis (AS) is the prototype for spondyloarthritis primarily affecting young men. Geographic and ethnic variations exist in the prevalence and severity of AS and relate to the wide disparity in the frequency of human leukocyte antigen (HLA)-B27, a major genetic risk factor. The strength of the disease association with HLA-B27 is lower in most Arab populations (25-75 %) than in Western European populations (>90 %), and there is no association in sub-Saharan Africa, where the prevalence of HLA-B27 is <1 %. Other epidemiologic differences between European and African populations are the apparent later age at presentation in sub-Saharan Africa, and the high rate of spondyloarthropathies associated with human immunodeficiency virus infection. Diagnosis of AS is often delayed 8-10 years; potential reasons for the delay in Africa and the Middle East include low awareness among physicians and patients, the requirement for radiographic evidence of sacroiliitis for diagnosis, and limited access to magnetic resonance imaging in some countries. Treatment should be initiated early to prevent or reduce skeletal deformity and physical disability. Nonsteroidal anti-inflammatory drugs are effective first-line treatment and anti-tumor necrosis factor-α drugs are indicated for patients who have an inadequate response to first-line therapy. In Africa and the Middle East, such treatments may be precluded either by cost or contraindicated because of the high prevalence of latent tuberculosis infection. Research is sorely needed to develop cost-effective tools to diagnose AS early as well as effective, inexpensive, and safe treatments for these developing regions.

Clinical, functional, and radiographic differences among juvenile-onset, adult-onset, and late-onset ankylosing spondylitis

OBJECTIVE

The aim of our study was to compare the clinical, functional, and radiographic outcomes at different ages of onset in patients with ankylosing spondylitis (AS).

METHODS

A total of 546 patients were enrolled consecutively and classified into 3 groups based on their age at symptom onset: (1) juvenile-onset AS (age ≤ 16 years; JoAS); (2) adult-onset AS (> 16 but < 40 years; AoAS); and (3) late-onset AS (≥ 40 years; LoAS). We compared the differences among the 3 groups. OR for disease outcomes were calculated and adjusted for sex, HLA-B27, and disease duration.

RESULTS

There were 67 patients (12.3%) with JoAS, 460 (84.2%) with AoAS, and 19 (3.5%) with LoAS. Male sex and HLA-B27 were associated with a younger age at onset (p < 0.001). Compared to patients with AoAS, patients with JoAS were more likely to present with peripheral arthritis, while patients with JoAS and LoAS were less likely to have back pain at the onset of AS (p < 0.05). After controlling for multiple covariates, JoAS was found to be associated with a worse functional outcome and global assessment, and a high serum immunoglobulin A level (p < 0.05). Patients with JoAS had less lumbar spinal radiographic severity (p < 0.05). There were no statistical differences in clinical or functional outcome between the LoAS and AoAS groups. None of the LoAS patients had radiographic hip involvement.

CONCLUSION

Sex and HLA-B27 are significantly associated with age at onset of AS. Both JoAS and LoAS have their distinctive symptoms/signs at onset and different disease outcomes.

Heparin elevates circulating soluble fms-like tyrosine kinase-1 immunoreactivity in pregnant women receiving anticoagulation therapy

BACKGROUND

Alterations in circulating levels of pro- and antiangiogenic factors have been associated with adverse pregnancy outcomes. Heparin is routinely administered to pregnant women, but without clear knowledge of its impact on these factors.

METHODS AND RESULTS

We conducted a longitudinal study of 42 pregnant women. Twenty-one women received prophylactic heparin anticoagulation, and 21 healthy pregnant women served as controls. Compared with gestational age-matched controls, heparin treatment was associated with increased circulating levels of soluble fms-like tyrosine kinase-1 (sFlt-1) in the third trimester (P<0.05), in the absence of preeclampsia, placental abruption, or fetal growth restriction. Heparin had no effect on circulating levels of vascular endothelial growth factor, placenta growth factor, or soluble endoglin as assessed by ELISA. In vitro, low-molecular weight and unfractionated heparins stimulated sFlt-1 release from placental villous explants, in a dose- and time-dependent manner. This effect was not due to placental apoptosis, necrosis, alteration in protein secretion, or increased transcription. Western blot analysis demonstrated that heparin induced shedding of the N-terminus of Flt-1 both in vivo and in vitro as indicated by a predominant band of 100-112 kDa. By using an in vitro angiogenesis assay, we demonstrated that serum of heparin-treated cases inhibited both basal and vascular endothelial growth factor-induced capillary-like tube formation.

CONCLUSIONS

Heparin likely increases the maternal sFlt-1 through shedding of the extracellular domain of Flt-1 receptor. Our results imply that upregulation of circulating sFlt-1 immunoreactivity in pregnancy is not always associated with adverse outcomes, and that heparin's protective effects, if any, cannot be explained by promotion of angiogenesis.

Modulation of amniotic fluid activin-a and inhibin-a in women with preterm premature rupture of the membranes and infection-induced preterm birth

PROBLEM

Activins and inhibins are important modulators of inflammatory processes. We explored activation of amniotic fluid (AF) activin-A and inhibin-A system in women with intra-amniotic infection and preterm premature rupture of the membranes (PPROM).

METHOD OF STUDY

We analyzed 78 AF samples: '2nd trimester-control' (n=12), '3rd trimester-control' (n=14), preterm labor with intact membranes [positive-AF-cultures (n=13), negative-AF-cultures (n=13)], and PPROM [positive-AF-cultures (n=13), negative-AF-cultures (n=13)]. Activin-A levels were evaluated ex-vivo following incubation of amniochorion and placental villous explants with Gram-negative lipopolysaccharide (LPS) or Gram-positive (Pam3Cys) bacterial mimics. Ability of recombinant activin-A and inhibin-A to modulate inflammatory reactions in fetal membranes was explored through explants' IL-8 release.

RESULTS

Activin-A and inhibin-A were present in human AF and were gestational age-regulated. Activin-A was significantly upregulated by infection. Lower inhibin-A levels were seen in PPROM. LPS elicited release of activin-A from amniochorion, but not from villous explants. Recombinant activin-A stimulated IL-8 release from amniochorion, an effect that was not reversed by inhibin-A.

CONCLUSION

Human AF activin-A and inhibin-A are involved in biological processes linked to intra-amniotic infection/inflammation-induced preterm birth.

Gender and disease features in Moroccan patients with ankylosing spondylitis

This study was conducted to determine differences in ankylosing spondylitis (AS) between men and women in terms of clinical characteristics, biological features, structural severity and quality of life (QoL). A total of 130 consecutive AS patients fulfilling the modified New York criteria were included. Sociodemographic data were collected. The activity of disease was assessed by the Bath ankylosing spondylitis disease activity index (BASDAI) and the functional disability by the Bath Ankylosing spondylitis functional index (BASFI). Spinal mobility was measured using the occiput-to-wall distance, chest expansion, Schober index and the Bath Ankylosing Spondylitis Metrology Index (BASMI). The Bath Ankylosing Spondylitis Radiologic Index (BASRI) was used to evaluate structural damage. Fatigue was evaluated using a visual analogue scale and the QoL was measured by using the generic instrument SF-36. Laboratory tests included the erythrocyte sedimentation rate (ESR) and the C-reactive protein (CRP). In our sample, there were 87 (66.9%) men and 43 (33.1%) women. Women had significantly lower educational levels but there were no differences in socioeconomic status, age at onset, diagnosis delay, disease duration or treatments. Also, women had higher clinical disease activity (morning stiffness and BASDAI score), higher number of tender joints, more severe enthesitis and higher scores of fatigue (for all p ≤ 0.05). Moreover, hip involvement was more prevalent in men and the impairment of spinal mobility was significantly worse compared to women (for all p ≤ 0.001). Men had worse radiographic damage and lower scores in physical and social domains of QoL, but there were no differences in functional impairment scores. In this study, we noticed that AS presents differently according to gender in our patients. More longitudinal studies seem to be necessary to identify gender-related parameters of disease, thing that may help in diagnosis and therapeutic management of our AS patients.

IL-6 trans-signaling system in intra-amniotic inflammation, preterm birth, and preterm premature rupture of the membranes

Classic IL-6 signaling is conditioned by the transmembrane receptor (IL-6R) and homodimerization of gp130. During trans-signaling, IL-6 binds to soluble IL-6R (sIL-6R), enabling activation of cells expressing solely gp130. Soluble gp130 (sgp130) selectively inhibits IL-6 trans-signaling. To characterize amniotic fluid (AF) IL-6 trans-signaling molecules (IL-6, sIL-6R, sgp130) in normal gestations and pregnancies complicated by intra-amniotic inflammation (IAI), we studied 301 women during second trimester (n = 39), third trimester (n = 40), and preterm labor with intact (n = 131, 85 negative IAI and 46 positive IAI) or preterm premature rupture of membranes (PPROM; n = 91, 61 negative IAI and 30 positive IAI). ELISA, Western blotting, and real-time RT-PCR were used to investigate AF, placenta, and amniochorion for protein and mRNA expression of sIL-6R, sgp130, IL-6R, and gp130. Tissues were immunostained for IL-6R, gp130, CD15(+) (polymorphonuclear), and CD3(+) (T cell) inflammatory cells. The ability of sIL-6R and sgp130 to modulate basal and LPS-stimulated release of amniochorion matrix metalloprotease-9 was tested ex vivo. We showed that in physiologic gestations, AF sgp130 decreases toward term. AF IL-6 and sIL-6R were increased in IAI, whereas sgp130 was decreased in PPROM. Our results suggested that fetal membranes are the probable source of AF sIL-6R and sgp130. Immunohistochemistry and RT-PCR revealed increased IL-6R and decreased gp130 expression in amniochorion of women with IAI. Ex vivo, sIL-6R and LPS augmented amniochorion matrix metalloprotease-9 release, whereas sgp130 opposed this effect. We conclude that IL-6 trans-signaling molecules are physiologic constituents of the AF regulated by gestational age and inflammation. PPROM likely involves functional loss of sgp130.

Health-related quality of life in Moroccan patients with ankylosing spondylitis

The main objective of this study was to assess the aspects of health-related quality of life (QOL) in patients with ankylosing spondylitis (AS) and to explore the disease-related parameters influencing it. One hundred patients with AS according to New York Classification criteria were recruited in this cross-sectional study. The Medical Outcomes Study Short Form 36 Health Survey (SF-36) was used to assess health-related QOL. Assessment criteria included the evaluation of disease activity (Bath Ankylosing Spondylitis Disease Activity index [BASDAI]), global well-being (Bath Ankylosing Spondylitis Global Index [BASGI]), enthesitis (Mander enthesis index [MEI]), functional status (Bath Ankylosing Spondylitis Functional Index [BASFI]); metrology (Bath Ankylosing Spondylitis Metrology Index [BASMI]) and radiographic damage (Bath Ankylosing Spondylitis Radiologic Index [BASRI]). In this study, males comprised 67% of the subjects; mean age was 38 ± 13 years and mean disease duration was 9.5 ± 6.8 years. Among these patients, 52% had hip involvement. Our patients had a moderately active disease and severe functional disability. All domains of SF-36 were deteriorated with low scores. The SF-36 subgroups most affected were role limitation (18.8 ± 28.1), role emotional (19.4 ± 35), general health (44.9 ± 20.3) and vitality (38.0 ± 18.2). Lower scores of SF-36 had good statistically significant correlations with altered functional status (BASFI), worse general well-being (BASGI), altered metrology (BASMI); and moderate correlations with high disease activity (BASDAI), important radiological damage (BASRI); restricted chest expansion and prolonged morning stiffness (p < 0.001). This study states that health-related QOL in Moroccan patients with AS is damaged in a significant way. Mental as well as physical aspects were affected. Functional disability, patient's well-being, metrology and disease activity are the main factors associated with deteriorating domains of QOL in AS. Recognizing complicated relationships between clinical measures and QOL in patients with AS can help us to develop further management strategies to improve their QOL.

Amniotic fluid angiopoietin-1, angiopoietin-2, and soluble receptor tunica interna endothelial cell kinase-2 levels and regulation in normal pregnancy and intraamniotic inflammation-induced preterm birth

BACKGROUND

Angiopoietin-1 (Ang-1) and Ang-2 act selectively on endothelial cells by engaging the Tunica interna endothelial cell kinase-2 (Tie2) receptor. A soluble form of Tie2 (sTie2) blocks angiopoietin bioactivity.

OBJECTIVE

The aim of the study was to characterize changes and expression patterns of Ang-1, Ang-2, and sTie2 in amniotic fluid (AF) and placenta during human pregnancy and intraamniotic inflammation (IAI)-induced preterm birth.

DESIGN AND SETTING

We conducted a cross-sectional study at a tertiary university hospital.

PATIENTS

AF levels of Ang-1, Ang-2, and sTie2 were evaluated in 176 women during second trimester (n = 40), third trimester (n = 37), and preterm labor (positive IAI, n = 50; negative IAI, n = 49). Placenta and cord blood of select women were analyzed.

MAIN OUTCOME MEASURES

Ang-1, Ang-2, sTie2, and IL-6 were evaluated by ELISA. Real-time PCR measured Ang-1, Ang-2, and Tie2 placental mRNA levels. Placenta was immunostained for Ang-1 and Ang-2. Placental explant cultures were stimulated with lipopolysaccharide, Pam3Cys, and modulators of protein synthesis/secretion (cycloheximide, monensin, and brefeldin A).

RESULTS

In normal pregnancy, the levels and ratios of AF Ang-1, Ang-2, and sTie2 varied with gestational age (GA) (P < 0.001). PCR revealed corresponding changes in placental Ang-1 and Ang-2, but not Tie2, mRNA. IAI raised AF Ang-1, Ang-2, and sTie2 above the expected level for GA without affecting their placental mRNA. Ang-2 immunoreactivity appeared enhanced in areas of villous edema. AF Ang-2/Ang-1 ratio was an important determinant of cord blood IL-6 (P < 0.001). Ex-vivo, sTie2 release was increased by Golgi disrupting but not bacterial mimic agents.

CONCLUSIONS

Ang-1, Ang-2, and sTie2 are physiological constituents of AF that are GA and IAI regulated. Ang-2/Ang-1 ratio may play a role in modulating the fetal inflammatory response to IAI. Placental sTie2 shedding likely involves a Golgi-mediated mechanism.