How to treat patients with thrombotic antiphospholipid syndrome in 2024?

Antiphospholipid syndrome encompasses a range of clinical conditions, particularly thrombotic or obstetrical manifestations, associated with the presence of antiphospholipid antibodies. Managing thrombotic antiphospholipid syndrome in daily clinical practice can be challenging and requires thorough risk stratification and tailored treatment strategies. Primary prophylaxis focuses on improving traditional thrombosis risk factors and, in certain situations, may include low-dose aspirin and / or prophylactic anticoagulants (e.g., low-molecular-weight heparin). The treatment of thrombotic antiphospholipid syndrome primarily involves long-term anticoagulation with vitamin K antagonists. In some cases, a combination of vitamin K antagonists and low-dose aspirin, vitamin K antagonists with international normalized ratio target >3 or a switch to therapeutic doses of low-molecular-weight heparin might be employed. The use of hydroxychloroquine is essential for patients with secondary systemic lupus erythematosus and may be considered for patients with recurrent thrombosis. In other selected situations, the use of immunomodulatory agents can be considered.

ANA-positive versus ANA-negative Antiphospholipid Antibody-positive Patients: Results from the APS ACTION Clinical Database and Repository.

OBJECTIVES: This study focused on the prevalence and impact of antinuclear antibodies (ANA) in antiphospholipid antibody (aPL)-positive patients without concomitant systemic autoimmune rheumatic diseases (SARDs). METHODS: Data from aPL-positive patients with or without Revised Sapporo APS classification criteria were retrieved from the APS ACTION Registry. Patients with concomitant SARDs were excluded. RESULTS: 430 aPL-positive patients were included in the analysis, 56% ANA-positive and 44% negative. ANA positivity was significantly associated with history of hematologic manifestations (persistent autoimmune hemolytic anaemia, thrombocytopenia, leukopenia and/or lymphopenia) (16% of ANA-positive vs 7% of ANA-negative, p= 0.006). Triple aPL-positivity was more frequent in the ANA-positive subgroup (p= 0.02), along with low baseline C3 and C4 levels (p= 0.05 and p= 0.009, respectively), and higher frequency for extractable nuclear antigens (ENA). Among aPL-positive patients with no APS classification, ANA-positive patients showed a higher rate of arthritis (p= 0.006). Among female patients who have experienced at least one pregnancy, 113 were ANA-positive and 96 were ANA-negative; ANA-negative patients had a higher number of pregnancies (p= 0.018), and number of live births (p= 0.014). A wider proportion of ANA-positive patients were treated with hydroxychloroquine (HCQ) (p< 0.001). CONCLUSION: When we analysed aPL-positive patients with no other SARDs, ANA status was not associated with thrombosis or pregnancy morbidity. Interestingly, ANA-positive patients showed higher rates of systemic autoimmune features, including hematologic manifestations, multiple aPL positivity, lower complement levels, ENA positivity, and joint involvement, and were more often treated with HCQ. Finally, aPL-positive subjects who were ANA-negative had a higher rate of pregnancies and live births.

Assessing the steroid-sparing effect of biological agents in randomized controlled trials for lupus: a scoping review.

Prompt disease control of flares in patients with systemic lupus erythematosus (SLE) is a priority in treatment strategy planning. However, the long-term dosage-related collateral effects of glucocorticoids (GCs) have pushed researchers towards the identification and utilization of novel biological agents that could both induce and maintain low disease activity and remission, especially in the context of lupus nephritis (LN). This scoping review aims at assessing the current evidence of the potential steroid-sparing effect of biologic therapies by reviewing phase II and phase III randomized, placebo-controlled trials involving SLE/LN patients. A scoping review of the literature was carried out in accordance with PRISMA-ScR recommendations. Risk of bias was assessed through the utilization of the Cochrane Collaboration's tool for randomized controlled trials (RCTs). Eight RCTs met the inclusion criteria and were included in this analysis (treatment drug, 7 belimumab; 1 anifrolumab). Four studies showed a definite steroid-sparing effect (treatment drug, 3 belimumab; 1 anifrolumab), while in the remaining four RCTs, the steroid-sparing effect was not observed. When focusing on phase III trials, the overall quality of the studies resulted fair or good considering the risk of bias. However, a degree of heterogeneity of steroid regimen protocol (considering initial dosage, tapering and rescue treatment allowance) was observed. While a growing body of evidence is supporting the safety and efficacy of biological treatment in SLE, the evidence on their steroid-sparing effect remains scattered. Future research needs to pursue the identification of precise SLE clusters of patients who would benefit most from a specific treatment protocol with a definite steroid-sparing effect.

Type I interferon pathway activation across the antiphospholipid syndrome spectrum: associations with disease subsets and systemic antiphospholipid syndrome presentation.

Introduction: While the type I interferon (IFN-I) pathway is crucial in autoimmunity, its role in antiphospholipid antibody (aPL)-positive subjects, including aPL carriers and antiphospholipid syndrome (APS) patients, is poorly understood. This study aims at characterizing IFN-I pathway activation within the spectrum of aPL-positive subsets. Methods: A total of 112 patients [29 aPL carriers, 31 primary APS (PAPS), 25 secondary APS (SAPS), 27 systemic lupus erythematosus (SLE) patients without aPL, and 44 healthy controls (HCs)] were recruited. IFI6, IFI44, IFI44L, MX1, IFI27, OAS1, and RSAD2 gene expression was evaluated in whole blood, and a composite index (IFN score) was calculated. Results: An overall activation of the IFN-I pathway was observed across the entire APS spectrum, with differences among genes based on the specific disease subset. The composite score revealed quantitative differences across subsets, being elevated in aPL carriers and PAPS patients compared to HCs (both p < 0.050) and increasing in SAPS (p < 0.010) and SLE patients (p < 0.001). An unsupervised cluster analysis identified three clusters, and correspondence analyses revealed differences in clusters usage across APS subsets (p < 0.001). A network analysis revealed different patterns characterizing different subsets. The associations between IFN-I pathway activation and clinical outcomes differed across APS subsets. Although no differences in gene expression were observed in systemic APS, the network analyses revealed specific gene-gene patterns, and a distinct distribution of the clusters previously identified was noted (p = 0.002). Conclusion: IFN-I pathway activation is a common hallmark among aPL-positive individuals. Qualitative and quantitative differences across the APS spectrum can be identified, leading to the identification of distinct IFN-I signatures with different clinical values beyond traditional categorization.

2023 ACR/EULAR classification criteria in existing research cohorts: an international study.

OBJECTIVE: To assess the impact of the updated ACR/EULAR APS classification criteria on two large research cohorts. METHODS: Consecutive patients who tested persistently positive for at least one aPL in the last three years were enrolled. The first APS Sydney index event was considered and computed for the comparison between Sydney and 2023 APS criteria. When computing the 2023 APS criteria, additional manifestations were also considered. RESULTS: The cohort comprised 249 patients (185 with APS and 64 aPL carriers according to Sydney criteria). The 185 patients had as first index event venous thrombosis in 55 cases (29.8%), arterial thrombosis in 63 (34%) and pregnancy morbidity in 67 (36.2%). When applying the updated criteria, 90 subjects (48.7%) failed to reach the composite score of the new criteria. The percentage of thrombotic APS per Sydney criteria decreased from 47.3% to 34.9% because of high cardiovascular risk in 23 cases, IgM aPL profile in six cases and in two patients for both reasons. Patients with pregnancy morbidity decreased from 26.9% to 3.2% (39 cases of recurrent early pregnancy loss and 20 of fetal losses). Consequently, the percentage of aPL carriers increased from 26% to 61%. When looking at the disease evolution at follow-up, 32 additional patients out of 90 (35.6%) fulfilled the new APS criteria, after developing additional clinical manifestation following index event. CONCLUSION: When applying the new APS criteria to our research cohorts, not-negligible differences exist in patients' classification. A multidisciplinary approach will be mandatory to assess the impact of the new criteria on research and, ultimately, patients' care.

Deciphering the clinical significance of longitudinal antiphospholipid antibody titers.

In antiphospholipid syndrome (APS), the risk of clinical manifestations increases with higher titers of antiphospholipid antibodies (aPL). Despite the adoption of aPL titers in the classification approach to aPL-positive subjects, the value of longitudinal monitoring of those titers in the follow-up is still debated, being well studied only in systemic lupus erythematosus (SLE). The literature suggests that the rate of aPL positivity decreases during follow-up in primary APS, estimating that seroconversion occurs in between 8.9 and 59% of patients over time. Negativisation of aPL occurs more frequently in asymptomatic aPL carriers than in patients with full-blown APS as well as in subjects with single aPL positivity or low aPL antibody titers. In patients with SLE, aPL typically behave fluctuating from positive to negative and back again in the course of follow-up. The few studies assessing the longitudinal course of aPL positivity with no associated systemic connective tissue disease reported a progressive decrement of aPL titers over time, in particular of antibodies against ß2 glycoprotein I (antiß2GPI) and cardiolipin (aCL) of IgG isotype. After a thrombotic event, aPL titers tend to decrease, as emerged from cohorts of both primary and secondary APS. Hydroxychloroquine has been identified as the most effective pharmacological agent to reduce aPL titers, with multiple studies demonstrating a parallel reduction in thrombosis rate. This review addresses available evidence on the significance of aPL titer fluctuation from clinical, therapeutic and pathogenic perspectives.

Pediatric Presentation of Antiphospholipid Syndrome: A Review of Recent Literature With Estimation of Local Prevalence.

We aimed to investigate the epidemiology, the clinical and laboratory characteristics of the pediatric involvement of antiphospholipid syndrome (APS), by performing a review of the current evidence and reviewing local experience in the Northwest Italy. To achieve this, we performed a detailed literature search to identify articles describing clinical and laboratory characteristics of pediatric APS. In concomitance, we conducted a registry-based study collecting data from the Piedmont and Aosta Valley Rare Disease Registry including pediatric patients diagnosed with APS in the last 11 years. The literature review led to inclusion of six articles with a total of 386 pediatric patients (65% females, 50% with systemic lupus erythematosus (SLE) as concomitant diagnosis). Rates of venous and arterial thrombosis were 57 and 35%, respectively. "Extra-criteria manifestations" included mostly hematologic and neurologic involvement. Almost one-quarter of patients (19%) reported recurrent events and 13% manifested as catastrophic APS. A total of 17 pediatric patients (mean age 15.1 ± 2.8, 76% female) developed APS in the Northwest of Italy. In 29% of cases, SLE was a concomitant diagnosis. Deep vein thrombosis was the most frequent manifestation (28%) followed by catastrophic APS (6%). The estimated prevalence of pediatric APS in Piedmont and Aosta Valley Region is 2.5/100,000 people, whereas the estimated annual incidence is 0.2/100,000 inhabitants. In conclusion, clinical manifestations of pediatric APS seem to be more severe and with a high prevalence of noncriteria manifestations. International efforts are needed to better characterize this condition and to develop new specific diagnostic criteria to avoid missed/delayed diagnosis in children with APS.

The estimated prevalence of antiphospholipid antibodies and criteria-antiphospholipid syndrome in subjects with renal thrombotic microangiopathy.

BACKGROUND: While the prevalence of antiphospholipid antibodies (aPL) in venous and arterial thrombotic events had already been estimated by previous studies, the prevalence of aPL in subjects with Thrombotic Microangiopathy (TMA) is still not fully elucidated. Thus, we conducted a systematic review to estimate the frequency of aPL in subjects with biopsy-proven renal TMA. METHODS: We conducted in the PubMed database a search for English-language studies investigating the presence of aPL in subjects with biopsy-proven renal TMA from January 1985 to December 2022. Keywords used in the search included: 'antiphospholipid syndrome', 'antiphospholipid antibodies' and 'thrombotic microangiopathy'. Cohorts of HUS patients were excluded due to the risk of over-estimating the prevalence of aPL in these populations. The median frequency for positive aPL including anticardiolipin antibodies (aCL), antibodies against ß2-glycoprotein-I (anti-ß2GPI) and lupus anticoagulant (LA) was then calculated. RESULTS: 522 articles were identified through the literature search. Six studies, assessing the prevalence of aPL in 211 subjects with renal TMA, were retrieved. The overall aPL prevalence was estimated as 24.4% (range 22-56). The estimated prevalence of aCL (IgG/IgM), anti-ß2GPI, (IgG/IgM) and LA was 4.0% (range 3-27), 4.0% (range 3-16) and 18.9% (range 13-25), respectively. APS was diagnosed in 16.3% (range 11-29) of the patients. Of note, a high level of heterogeneity was observed when comparing the reported aPL profiles for each study. CONCLUSIONS: This comprehensive systematic analysis of studies investigating the prevalence of aPL in renal TMA showed that, despite the high heterogeneity of the included studies, aPL are present in about one case out of four renal-TMA cases.

16th International congress on antiphospholipid antibodies task force report on antiphospholipid syndrome laboratory diagnostics and trends.

Classification criteria for antiphospholipid syndrome (APS) require IgG or IgM isotypes of the anticardiolipin (aCL) antibodies, anti-ß2 glycoprotein I (anti-ß2GPI) antibodies, and/or the lupus anticoagulant (LA) to satisfy the laboratory disease definition. Over the past 20 years, non-criteria antiphospholipid antibodies (aPL) directed to other proteins of the coagulation cascade (i.e. prothrombin and/or phosphatidylserine-prothrombin complex) or to some domains of ß2GPI have been proposed. This task force concentrated and reviewed the literature on data including aPS/PT, antibodies to domain 4/5 of ß2GPI and the newly described antibodies to protein/HLA-DR complex. In addition, we discussed testing of LA in the 'new' oral anticoagulants' era and the value of triple positivity in the risk assessment of aPL. The conclusions were presented at a special session during the 16th International Congress on aPL, Manchester, UK, September 2019.

Thrombosis and APS: Lessons Learned from Another Black Swan Tale.

Antiphospholipid syndrome (APS) is a chronic systemic autoimmune disease characterized by venous, arterial, and microvascular thromboses and/or recurrent pregnancy morbidity, that occur in the persistent presence of antiphospholipid antibodies (aPL). APS can present with a wide range of clinical manifestations often reffered as "extra-criteria". These features, although apparently less common, can severely impact patients' outcome. Here, we report the case of a patient with a newly diagnosed APS. He previously experienced a recurrence of venous thrombosis after discontinuation of anticoagulant therapy in association with cutaneous ulcerations as presenting symptoms. Interestingly, skin lesions did not improve with full anticoagulant treatment. Due to concomitant presence of thrombotic and microvascular involvement, immunomodulatory therapy with steroid pulses followed by intravenous injections of belimumab was started, with progressive and significant amelioration, leading to complete recovery. Following the presentation of the current case report, we highlight the importance of suspecting APS in young patients experiencing unprovoked thrombosis. We also emphasized the critical issue of testing aPL during anticoagulant treatment and focused on the need of aPL retesting in patients with positivity at high titers. We also highlight the double nature of aPL-mediated clinical manifestations. While most patients presented with pure thrombotic complications, one should always remember that APS is an autoimmune-mediated disease, which can benefit from alternative therapeutic approaches beyond anticoagulation.

Complement levels during the first trimester predict disease flare and adverse pregnancy outcomes in systemic lupus erythematosus: A network meta-analysis on 532 pregnancies.

BACKGROUND: Complement levels have been proposed as candidate biomarkers of disease activity and obstetric risk in systemic lupus erythematosus (SLE) pregnancies, but their reliability has been questioned due to the physiologic fluctuations of complement during gestation. Thus, this network meta-analysis aimed at assessing the clinical significance of complement fluctuations in lupus pregnant women. METHODS: Corresponding authors of 19 studies meeting inclusion criteria were invited to contribute with additional data including C3 and C4 levels [before pregnancy, at conception, in every trimester (T) and 3 months after delivery]; data were pooled together in a network meta-analysis. RESULTS: A total of 532 lupus women from four studies were included in the analysis. In SLE women, C3 and C4 increased progressively during gestation: levels remained stable during T1 and peaked in T2 to decrease in T3. Patients with previous lupus nephritis (LN) and those who experienced flares during pregnancy had significantly lower mean levels of C3 and C4 at all timepoints. The lowest levels of complement were observed, particularly during T1, in patients with LN and gestational flare. Both reduction and the lack of increase of C3 and C4 levels at T1 versus conception were associated with gestational flares, particularly in LN patients. Pregnancies with flare had a statistically significant higher rate of maternal and fetal complications(60% versus 50.3%; p = 0.03). CONCLUSIONS: Low complement levels, particularly in T1, were associated with a higher frequency of gestational flare. Either reduction or smaller increase of C3 and/or C4 levels, even within normal range, might predict flares especially in early gestation.

Safety and efficacy of pre-exposure prophylaxis with tixagevimab/cilgavimab (Evusheld) in patients with glomerular diseases who received rituximab.

Background: Patients on B-cell-depleting agents may have a suboptimal response to vaccination, placing them at a higher risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or suffering from a more severe prognosis. Indeed, available data on pre-exposure prophylaxis with tixagevimab/cilgavimab (Evusheld) in subjects with glomerular diseases (GDs) who received rituximab are limited. Methods: We conducted a prospective study analysing the safety and efficacy of tixagevimab/cilgavimab for pre-exposure prophylaxis in patients with GDs who received rituximab in the previous 12 months. The rates of symptomatic infections and hospitalizations were compared with those for patients with GD treated with rituximab who refused to receive tixagevimab/cilgavimab. Results: Tixagevimab/cilgavimab was administered to 22 patients (12 females, mean age 58.4 ± 19.6 years) with GD diagnoses including membranous nephropathy, lupus nephritis, anti-neutrophil cytoplasmic antibody-associated vasculitis and focal segmental glomerulosclerosis. No patient treated with tixagevimab/cilgavimab experienced symptomatic infection with SARS-CoV-2 during the follow-up (mean observation time of follow-up was 112 ± 23 days), while 11 of 28 controls (39.3%) reported a symptomatic infection (P = .0001), requiring hospitalization in 2 cases. Reported adverse events were mild, namely self-limiting headache [4], discomfort at the injection site [3], flu-like symptoms/myalgia [3] and fever [1]. No serious adverse events (e.g. cardiac events, anaphylaxis) were reported. Conclusion: Pre-exposure prophylaxis with tixagevimab/cilgavimab seems safe and lowered the risk of symptomatic SARS-CoV-2 infection by ≈40% in vaccinated subjects with GD who received anti-CD20 therapy. Possible applications in the subset of patients who need immunosuppressive therapy, especially with rituximab, in a pandemic setting might be envisaged.

New Frontiers in Autoimmune Diagnostics: A Systematic Review on Saliva Testing.

(1) Background: Immunological laboratory testing is known to be complex, and it is usually performed in tertiary referral centers. Many criticalities affect diagnostic immunological testing, such as limited availability, the need for specifically trained laboratory staff, and potential difficulties in collecting blood samples, especially in the most vulnerable patients, i.e., the elderly and children. For this reason, the identification of a new feasible and reliable methodology for autoantibody detection is urgently needed. (2) Methods: We designed a systematic review to investigate the available literature on the utilization of saliva samples for immunological testing. (3) Results: A total of 170 articles were identified. Eighteen studies met the inclusion criteria, accounting for 1059 patients and 671 controls. The saliva collection method was mostly represented by passive drooling (11/18, 61%), and the most frequently described methodology for antibody detection was ELISA (12/18, 67%). The analysis included 392 patients with rheumatoid arthritis, 161 with systemic lupus erythematosus, 131 with type 1 diabetes mellitus, 116 with primary biliary cholangitis, 100 with pemphigus vulgaris, 50 with bullous pemphigoids, 49 with Sjogren syndrome, 39 with celiac disease, 10 with primary antiphospholipid syndromes, 8 with undifferentiated connective tissue disease, 2 with systemic sclerosis, and 1 with autoimmune thyroiditis. The majority of the reviewed studies involved adequate controls, and saliva testing allowed for a clear distinction of patients (10/12 studies, 83%). More than half of the papers showed a correlation between saliva and serum results (10/18, 55%) for autoantibody detection, with varying rates of correlation, sensitivity, and specificity. Interestingly, many papers showed a correlation between saliva antibody results and clinical manifestations. (4) Conclusions: Saliva testing might represent an appealing alternative to serum-based testing for autoantibody detection, considering the correspondence with serum testing results and the correlation with clinical manifestations. Nonetheless, standardization of sample collection processing, maintenance, and detection methodology has yet to be fully addressed.

Clinical-Pathological Characteristics of Renal Injuries Identify Different Clusters in Patients With Antiphospholipid Antibodies.

Introduction: Significant heterogeneity still exists in the nomenclature of renal involvement in antiphospholipid syndrome (APS). Methods: We applied a hierarchical cluster analysis to determine subgroups of patients according to clinical, laboratory, and renal histology characteristics in a cohort of subjects with confirmed antiphospholipid antibodies (aPL) positivity and biopsy proven aPL-related renal injuries. Kidney outcomes were then assessed at 12 months. Results: A total of 123 aPL-positive patients were included in the study (101 [82%] female, 109 [88.6%] with systemic lupus erythematosus [SLE], 14 (11.4%) with primary APS [PAPS]). Three clusters were identified. Twenty-three patients (18.7%) were included in the first cluster (cluster 1), characterized by a higher prevalence of glomerular capillary and arteriolar thrombi and fragmented red blood cells in the subendothelial space. Cluster 2 included 33 patients (26.8%) and showed a higher prevalence of fibromyointimal proliferative lesions as seen in hyperplastic vasculopathy. Cluster 3 was the largest (67 patients, mainly with SLE) and was characterized by higher prevalence of subendothelial edema, of both glomerular capillaries and arterioles. Conclusion: Three different clusters of patients with aPL and renal injuries emerged from our study as follows: the first, with the worst renal prognosis, was associated with features of thrombotic microangiopathy (TMA), thrombosis, triple aPL positivity and higher adjusted Global APS Score (aGAPSS) values; the second, characterized by hyperplastic vasculopathy with an intermediate prognosis, was seen more frequently in patients with cerebrovascular manifestations; and the third, more benign in terms of outcomes and with no overt association with thrombotic features, was characterized by endothelial swelling in concomitant lupus nephritis (LN).

Chasing the Zebra: a case of membranous-like Glomerulopathy with SSA/RO52 deposits and no overt connective tissue disease.

BACKGROUND: The nature of the deposits in immune-mediated glomerulonephritis with a membranous pattern and masked IgG-Kappa deposits (MGMID) remains still to be elucidated. CASE PRESENTATION: We present a case of 33-year-old woman developing a continuous asymptomatic proteinuria (0.8-1 g/24 h) with no overt connective tissue diseases. She tested positive at high titers for SSA antibodies (Ro52 838 UI/mL, Ro60 2716 UI/mL) and at the kidney biopsy histological findings were compatible with an immune-mediated glomerulonephritis with a membranous pattern and masked IgG-Kappa deposits. Also, we demonstrated a positive immunohistochemistry staining for anti-Ro52-SSA antibodies, with a granular positivity in mesangium and along rare glomerular capillaries. To date, only one case of a patient with overt diagnosis of Sjögren's syndrome with MGMID has been described but a pathogenic role for SSA and SSB antibodies has never been proven. CONCLUSIONS: In this case, we described for the first time by immunohistochemistry a Ro52+ granular positivity in the mesangium and glomerular capillaries, potentially paving the way for a better understanding of MGMID.

Health inequalities and social determinants of health: The role of syndemics in rheumatic diseases.

A syndemic is the co-existence of two or more health problems (including both social and biological features) that adversely influence each other with negative consequences on disease outcomes and perpetuation of inequalities. The syndemic approach can be applied to better understand the course of rheumatic musculoskeletal diseases (RMD) involving the study of adverse biological pathways and social determinants of health (SDH) all under the same framework. Identifying if a syndemic exists within RMDs may include investigating the synergic interactions between comorbidity (e.g., diabetes, obesity, chronic kidney diseases) and the concomitant of other adverse conditions (e.g., drug non-adherence, substance abuse), along with SDHs such as low household income, unemployment, low education, limited access to health care, as well as racial/ethnic discrimination. For decades, the understanding of RMDs progression has been based on causality, rather than investigating the kaleidoscopic web of connections that can potentially influence a disease course. The co-existence of health burdens in vulnerable populations, including those with RMD, specifically in certain socioeconomic groups, calls for new ways and strategies of thinking to improve our understanding of risk factors and co-morbidities to offer tailored interventions for clinical medicine and public health policy.

Finding the Needle in the Haystack: Serological and Urinary Biomarkers in Behçet's Disease: A Systematic Review.

Urinary and serological markers play an essential role in the diagnostic process of autoimmune diseases. However, to date, specific and reliable biomarkers for diagnosing Behçet's disease (BD) are still lacking, negatively affecting the management of these patients. To analyze the currently available literature on serological and urinary BD biomarkers investigated in the last 25 years, we performed a systematic literature review using the Population, Intervention, Comparison, and Outcomes (PICO) strategy. One hundred eleven studies met the eligibility criteria (6301 BD patients, 5163 controls). Most of them were retrospective, while five (5%) were prospective. One hundred ten studies (99%) investigated serological biomarkers and only two (2%) focused on urinary biomarkers. One hundred three studies (93%) explored the diagnostic potential of the biomolecules, whereas sixty-two (56%) tested their effect on disease activity monitoring. Most articles reported an increase in inflammatory markers and pro-oxidant molecules, with a decrease in antioxidants. Promising results have been shown by the omics sciences, offering a more holistic approach. Despite the vast number of investigated markers, existing evidence indicates a persistent gap in BD diagnostic/prognostic indices. While new steps have been taken in the direction of pathogenesis and disease monitoring, international efforts for the search of a diagnostic marker for BD are still needed.