P063 Consensus-based recommendations for treat to target management of immunoglobulin A vasculitis

Background

IgAvasculitis (IgAV) is the commonest cause of vasculitis in childhood.

It is characterized by small vessel vasculitis of the skin, gastrointestinal tract, kidneys, joints, and, rarely, the lungs and the central nervous system. There is paucity of international guidelines for management of IgA V. the Objective is to develop guidelines specific for Egyptian children with IgA vasculitis.

Method

This study was carried out to achieve an Egyptian expert consensus on a treat-to-target management strategy for IgA vasculitis using Delphi technique. The preliminary scientific committee identified a total of 16 key clinical questions according to the Patient/Population, Intervention, Comparison, and Outcomes (PICO) approach. Delphi process was implemented (2-rounds) to reach a consensus.

Results

An online questionnaire were sent to expert panel (n = 26) who participated in the two rounds. At the end of round 2, a total of 20 recommendation items, categorized into 2 sections were obtained. Agreement with the recommendations (rank 7–9) ranged from 91.7–100%. Consensus was reached (i.e. ≥75% of respondents strongly agreed or agreed) on the wording of all the 20 clinical standards identified by the scientific committee. Algorithms for the management have been suggested.

Conclusion

This was an expert, consensus recommendations for the diagnosis and treatment of IgA V and IgA V nephritis, based on best available evidence and expert opinion.

P016 Updated Clinical Practice Guidelines for JIA management adopting Treat to Target approach: the Egyptian College of Paediatric Rheumatology initiative

Background

There is an unmet need from paediatric rheumatologists and rheumatologists, managing children with JIA, for a well formulated guidelines aiming at achieving better outcomes of their patients. To establish adequate and easily adopted guidelines in management of different variants of JIA in a relatively low resources country.

Method

This study was carried out to achieve an Egyptian expert consensus on a treat-to-target management strategy for Juvenile Idiopathic Arthritis using Delphi technique. The preliminary scientific committee identified a total of 17 key clinical questions according to the Patient/Population, Intervention, Comparison, and Outcomes (PICO) approach. An evidence-based, systematic, literature review was conducted to compile evidence for the benefits and harms associated with JIA treatments. The core leadership team identified researchers and clinicians with expertise in JIA management in Egypt upon which Experts were gathered from different governorates and health centres across Egypt. Delphi process was implemented (2-rounds) to reacha consensus on the management recommendations of Egyptian JIA patients. Results: An online questionnaire were sent to expert panel (n = 27), of whom 26 participated in the two rounds. At the end of round 2, a total of eighteen (18) recommendation items, categorized into 4 sections to address the main 4 JIA categories, were obtained. Agreement with the recommendations (rank 7–9) ranged from 83.2–100% (average 86.8%). Consensus was reached (i.e. ≥75% of respondents strongly agreed or agreed) on the wording of all the 18 clinical standards identified by the scientific committee. Algorithms for the management of JIA polyarthritis, oligoarthritis and systemic JIA have been suggested.

Conclusion

A wide and representative panel of experts established a consensus regarding the management of JIA in Egypt. The developed guidelines provide a comprehensive approach to the management of JIA for ll Egyptian healthcare professionals who are involved in its management for follow up and frequent evaluation of these guidelines.

P050 Consensus based practice guidelines for the management and treatment of Juvenile familial Mediterranean fever: the Egyptian College of Paediatric Rheumatology initiative

Background

Familial Mediterranean fever (FMF) is the most common monogenic auto-inflammatory disease, with the highest prevalence amongst Mediterranean countries including Egypt (where there is high carrier rate of MEFV gene), characterized by recurrent attacks of fever and polyserositis. Mutations in the MEFV gene encoding pyrin has been associated with the disease, which causes exaggeration of the inflammatory response through uncontrolled interleukin production. Issuing updated treatment recommendations are vital for the treating healthcare professionals to get well acquainted with its diagnosis & treatment. To produce consensus-based recommendations to guide the early diagnosis, management and follow-up of patients with FMF.

Methods

The Patient/Population, Intervention, Comparison, and Outcomes (PICO) questions were developed and refined by the core team.

A qualitative synthesis of scientific evidence based on systematic review and clinical experience was conducted to compile evidence for the diagnosis and management of FMF.

A consensus process was conducted among the expert panel to generate the final recommendations and grade their strength.

3 rounds of Delphi process were carried out.

Results

Following 3 Delphi rounds, recommendations were developed for: early diagnosis, who to treat, treatment targets, genetic testing and its interpretation in association with clinical presentation, treatment of FMF and dealing with acute attacks, monitoring of management, identify treatment response, systemic affection, persistent attacks or inflammation, resistant cases, protracted symptoms, as well as remission status.

Algorithm for patients’ diagnosis and management is provided.

The final document comprises 12 recommendations, each presented with its degree of agreement (0–10), Level of agreement, grade of recommendation and rationale. The degree of agreement was >7/10 in all instances.

Conclusion

This guideline provides comprehensive approach to the accurate diagnosis and effective management/monitoring of FMF. It also represents a model for the incorporation of medical genetics practice into the more traditional domains of general medicine.

Impact of miR-155 (rs767649 A>T) and miR-146a (rs57095329 A>G) polymorphisms in System Lupus Erythematosus susceptibility in an Egyptian cohort

OBJECTIVE

Systemic Lupus Erythematosus (SLE) is an autoimmune inflammatory disease. miR-155 and miR-146a were expressed in many autoimmune diseases such as rheumatoid arthritis. The aim of this study was to examine miR-155 rs767649 and miR-146a rs57095329 polymorphisms in SLE susceptibility in an Egyptian cohort and to investigate the correlation between them and clinical data and disease activity.

PATIENTS AND METHODS

The two SNPs were analyzed in 120 patients with SLE and 100 healthy controls using RT-PCR.

RESULTS

The TT genotype and T allele of miR-155 rs767649 were associated with a significant increase in the risk of SLE, particularly in females. On the other hand, miR-146a (rs57095329) polymorphism was not associated with SLE risk. The AT/TT genotypes of miR-155 rs767649 showed higher distributions among patients with higher SLEDAI and nephritis.

CONCLUSIONS

This study had demonstrated for the first time the association between miR-155 rs767649 and the risk of development of SLE in an Egyptian cohort, mostly in females.

Association of miR-146a rs57095329 with Behçet's disease and its complications

BACKGROUND

Behçet's disease is a chronic relapsing and remitting autoimmune multisystem inflammatory disease characterised by oral aphthae, genital ulcers, skin lesions, gastrointestinal involvement, arthritis, vascular lesions and neurological manifestations. We hypothesised a link between rs57095329 of miR-146a and Behçet's disease, with further links with common clinical features.

METHODS

We tested our hypothesis in 130 Behçet's disease patients and 131 age and sex-matched healthy controls. Behcet's disease current activity index (BDCAI) was used to assess patients' disease activity status. MiR-146a (rs57095329) was genotyped in all participants using RT-PCR and results in patients analysed according to clinical features.

RESULTS

The frequency of the GG and AG genotypes in rs57095329 were strongly associated with Behçet's disease (adjusted OR 8.05, 95% CI 3.63-17.82; P < 0.001 and OR 2.26, 95% CI 1.27-4.04; P = 0.006, respectively), and in dominant (GG+AG > AA) and recessive (GG > AA+AG) models (both P < 0.001). Additionally, G allele distribution was significantly greater in Behçet's disease compared with controls (OR 2.85, 95% CI 1.98-4.11, P < 0.001). The AA genotype and A allele were linked to oral ulcers, the GG genotype and G allele to neurological disease, and the GG genotype and G allele to ocular disease (all P < 0.01). There were no links with genital ulceration, skin lesions, vascular disease or the result of the pathergy test.

CONCLUSION

The miR-146a (rs57095329) is associated with Behçet's disease and certain genotypes and alleles with oral ulcers, and with ocular and neurological manifestations.

Serum long noncoding RNAs FAS-AS1 & PVT1 are novel biomarkers for systemic lupus erythematous

Background: Systemic Lupus Erythematous (SLE) is a chronic systemic autoimmune disorder whose diagnosis depends on combination of multiple factors. Circulating lncRNAs could serve as diagnostic non-invasive biomarkers for SLE. We hypothesised that serum FAS-AS1 and PVT1 are new biomarkers for SLE that relate to clinical features and laboratory markers. Materials and Method: Measurement of serum FAS-AS1 & PVT1 by qRT-PCR, analysis of the association between two RNAs and the clinical data, activity index and laboratory markers by standard routine methods. Results: There was a significant relative increased serum FAS-AS1 (median (IQR) 2.19 (0.13-8.62) and a significant reduced PVT1 (median (IQR) 0.52 (0.01-7.55) in SLE patients compared to controls (P < 0.0001 for FAS-AS1 and = 0.007 for PVT1). Serum FAS-AS1 and PVT1 were positively correlated (r= 0.37, P = 0.001). Higher FAS-AS1 was significantly linked with nephritis (P = 0.011), positive anti-dsDNA (P= 0.01) and lower serum PVT1 was significantly associated with oral ulcers (P= 0.023), photosensitivity (P= 0.017), and neurological manifestations (P= 0.041). Serum PVT1 negatively correlated with age (r= -0.52, P< 0.0001) and ESR level (r= -0.29, P= 0.011) in SLE patients. No correlation between disease activity and serum FAS-AS1 or PVT1 was detected. Conclusions: Our study provides evidence that serum FAS-AS1 and PVT1 are new biomarkers for SLE.

Anti-PLA2R and anti-THSD7A as Diagnostic Serological Markers of Idiopathic Membranous Nephropathy: A Single Centre Study

Idiopathic Membranous Nephropathy (IMN) is a renal-limited autoimmune disease and accounts for approximately 80% of MNs. This study aimed to evaluate the role of circulating Anti-PLA2R and anti-THSD7A autoantibodies in the diagnosis and differentiation between primary and secondary MN. This study was conducted on 58 adult patients with biopsy-proven membranous glomerulopathy (MGN). All were subjected to measurement of Anti-PLA2R1 by an Enzyme-Linked Immunosorbent Assay and anti-THSD7A was detected by an indirect immunofluorescence assay. Among the 58 patients, 79.3% were diagnosed as IMN, and 20.7% as secondary membranous glomerulopathy (SMN). Among IMN patients, 32 patients (69.6%) showed positive anti-PLA2R1 antibodies, 2 patients (4.3%) were positive for anti-THSD7A antibodies and the remaining 12 patients (26.1%) were negative for both types of antibodies. Patients with SMN were negative for the two antibodies. The IMN patients had lower serum creatinine compared to the SMN patients (P=0.017). In conclusion, the study demonstrates that approximately 70% of patients with idiopathic membranous nephropathy have antibodies against PLA2R indicating that Anti-PLA2R may be fast, easy, relatively sensitive, and non-invasive test for diagnosis of IMN..

Association of Genetic Variants of the Interleukin-17F rs763780 and its Circulating Level in Psoriasis Patients in Egypt

Psoriasis is a chronic autoimmune disease affecting the skin and joints, IL- 17 family has been shown to be the major effector cytokine in its pathogenesis. This study aimed to investigate genetic polymorphism of IL-17F (rs763780) and evaluate the impact of this polymorphism on circulating levels of IL-17F as a potential risk locus for psoriasis. 60 patients suffering from chronic plaque psoriasis and 60 healthy controls were genotyped for the IL-17F (rs763780) using an Amplification Refractory Mutation System -PCR (ARMS-PCR) method. Measurement of serum IL-17F was also done by ELISA. There was a significant difference in frequency between TT and TC genotypes (OR= 2.74, 95%CI=1.04 -7.4, P=0.04) and TT and CC genotypes (OR=10.9, 95%CI=1.3-91.3, P=0.007). Moreover, the TC and CC genotypes were associated with increased risk of psoriasis in comparison with the TT genotype. (OR= 3.8, 95% CI: 1.5- 9.4, P= 0.003). The mutant allele, C, was significantly associated with an increased risk of psoriasis compared to that with the wild T allele, T (OR= 4.1, 95% CI: 1.9- 9.1, P= 0.0002). Serum level of IL-17F was higher among psoriasis patients (‎25.7±3.8pg/ml) than healthy controls ((15.1±2.1‎‎pg/ mL). In conclusion, IL17F polymorphism (rs763780) is associated with increased risk of psoriasis and may influence the level of production of IL-17F with subsequent effects on the pathogenesis of psoriasis.

Combination of Procalcitonin, CRP and CD11b Biomarkers in Early Detection of Neonatal Sepsis

The study aimed at comparing the diagnostic performances of CRP, PCT and CD11b in neonatal sepsis and evaluating the effectiveness of the sepsis score system when using a combination of various biomarkers. The study was conducted on 90 neonates divided into 3 equal groups; a group with proven sepsis, suspected sepsis and healthy newborns. All were subjected to measurement of CPR by Latex agglutination, serum Procalcitonin by ELISA and CD11b by flow cytometry. On comparing the three biomarkers; PCT (Serum procalcitonin) was associated with the highest (AUC) area under the curve followed by CD11b and CRP recording the smallest value. However, the AUC of the combined sepsis score was much higher than individual biomarkers. Although the sensitivity of individual biomarkers from procalcitonin to CD11b and lastly CRP but the sensitivity and specificity of the sepsis score showed higher values compared to those of individual biomarkers. In conclusion, the study demonstrate that combination of CRP, CD11b and, procalcitonin can enhance diagnostic discriminative power over traditional tests and overcome the drawbacks of each test alone with greater diagnostic accuracy.

Toll Like Receptor-4 Gene Polymorphism and Susceptibility to Pulmonary Tuberculosis

Tuberculosis (TB) affects human life globally for a long time. The difference in clinical outcome of infection suggests that host genetic makeup is responsible for such variability. Toll like receptors (TLRs) are pattern recognition receptors and have a significant role in mycobacterial recognition by the innate immune system. TLR-4 is the key receptor in initiation of innate immunity against M. tuberculosis. This study investigated whether variants in TLR-4 896A/G (Asp299Gly) and TLR-4 1196C/T (Thr399Ile) genes are related with susceptibility or resistance to pulmonary tuberculosis (PTB) in Saudi population. Genotyping of TLR-4 896A/G, TLR-4 1196C/T gene was performed by polymerase chain reaction followed by restriction fragment length polymorphism (PCR -RFLP) in 60 PTB patients and 60 control subjects. The A allele at (896A/G) was more frequent in the control group while G allele was more common in PTB patients. The frequency of T allele of (1196C/T) polymorphism was significantly increased in PTB patients as compared to the control group (P < 0.001; Odds ratio (OR) 2.79, 95% Confidence interval (CI) 1.65-4.72). A trend toward increased frequency of TT and CT genotypes of TLR4 at (1196C/T) were also observed in PTB patients as compared to control group (48.3% vs. 26, 7%, and 21.7% vs. 15%), respectively. This study suggests that that TLR4 polymorphism especially TLR4 rs4986791 may be associated with increase susceptibility to pulmonary tuberculosis, and C allele of rs4986791 is a promising protective factor for tuberculosis susceptibility in Saudi population.

Expression of CD64 on Surface of Circulating Monocytes in Systemic Lupus Erythematosus Patients: Relation to Disease Activity and Lupus Nephritis

CD64 is a type of integral membrane glycoprotein known as FC receptor that binds monomeric IgG-type antibodies with high affinity. It is more commonly known as FC gamma receptor 1 (FC?R1) and it is expressed on monocytes surface. The goal of this study was to investigate the association of CD64 expression on the surface of peripheral blood monocytes of systemic lupus erythematosus patients with disease activity, and lupus nephritis. 30 SLE patients were enrolled into this study. They were subdivided into: 15 SLE patients with lupus nephritis and 15 SLE patients without lupus nephritis. In addition,Together with 25 age and sex matched healthy volunteers were enrolled as controls group. Disease activity was defined by SLE Disease Activity Index (SLEDAI) score and the renal Systemic Lupus Erythematosus Disease Activity Index (rSLEDAI) score. Surface expression of CD64 on peripheral blood monocytes was evaluated by Flowcytometry. Renal biopsies of Lupus nephritis patients was obtained and evaluated using the International Society of Nephrology/Renal Pathology Society (ISN/RPS) classification scheme. There was a statistically significant difference in surface expression of CD64 on circulating monocytes (P > 0.001) in SLE patients with nephritis especially those with class II/III as compared to SLE without nephritis and healthy controls. The mean fluorescent intensity of CD64 staining correlated positively with markers of systemic inflammation, lupus nephritis, SLEDAI and rSLEDAI scores. In conclusions, surface expression of CD64 on circulating monocytes reflects systemic inflammation, renal injury and could be used as a rapid approach and good biomarker for disease activity and lupus nephritis in SLE patients.

Transfusion-transmitted virus infection in hemodialysis patients in Arar, Saudi Arabia: Prevalence, predictors and genotyping

Transfusion-transmitted virus (TTV) is a single-stranded DNA virus that was identified in patients with post-transfusion hepatitis of non-A-to-G type. Patients with chronic renal failure on maintenance hemodialysis (HD) have a higher risk of viral infections, and the prevalence of TTV infection is common. The aim of our study was to detect TTV-DNA and its genotype in HD patients. A case-control study compromising of 63 patients on maintenance HD therapy at the Nephrology Center of Central Arar Hospital and 100 healthy individuals who were tested for TTVDNA and its genotype by semi nested-polymerase chain reaction with primers derived from the conserved open reading frame 1 (ORF1) region followed by digestion with NdeI and PstI restriction enzyme. The results show that the prevalence of TTV in HD patients was high and statistically significant; 42.9% compared with 19% in the control group. History of blood transfusion was the only significant predictor, and we found that age of patients, duration of HD, hepatitis B and C infection, aspartate aminotransferase and alanine aminotransferase levels were not significant predictors of TT virus positivity in HD patients. TTV genotype 1 (G1) was found to be the most common genotype among both HD and healthy controls. The prevalence of TTV among HD patients was significantly higher than that in healthy individuals. History of blood transfusion was the only significant predictor of TTV positivity among them. Genotype 1 was the most predominant type among HD and healthy individuals. Further studies on TTV in peritoneal dialysis patients and transplant patients are needed.

Serum Level of Interleukin-37 and Expression of Its mRNA in Ankylosing Spondylitis Patients: Possible Role in Osteoporosis

Ankylosing spondylitis (AS) is a chronic inflammatory disease of the axial skeleton.Interleukin-37 (IL-37) is a member of IL-1 family cytokines, that downregulate expression of pro-inflammatory cytokines in chronic inflammatory diseases. The aim of the work is to investigate role of IL-37 in AS disease activity and osteoporosis. Twenty-five patients with AS and 25 controls were enrolled into this study. They were subjected to full clinical examination including assessment of disease activity according to the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Serum IL-37 levels and IL-37 mRNA relative concentration were measured by enzyme-linked immunosorbent assay (ELISA)‎ and quantitative reverse transcriptase- polymerase chain reaction (RT-PCR) respectively. Bone mineral density (BMD) was determined using dual energy X-ray absorptiometry (DEXA). Spine radiographs were scored using the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). Mean serum IL-37 level was significantly higher in AS patients compared with the ‎controls (P < 0.001) and significantly elevated in AS ‎patients with osteoporosis (P < 0.05). IL-37 mRNA gene expression showed a significant increase expression in active AS patient (25 folds) as well as in inactive patient (12 folds) as compared to ‎controls‎.‎ In conclusion, serum IL-37 and its mRNA expression is increased in ‎AS patients with special ‎consideration in patient with Osteoporosis and ‎correlates with disease activity and ‎BMD which indicate that IL-37 may provide a novel research ‎target for pathogenesis and therapy of AS.‎.

Serum Interleukin-33 in Behcet's Disease: Its Relation to Disease Activity and Clinical Manifestations

Behcet's disease (BD) is a chronic systemic inflammatory disorder characterized by a ‎‎course of remissions and exacerbations of unpredictable frequency and duration‎. Pro-‎inflammatory cytokines seem to be responsible for the enhanced inflammatory ‎‎response in BD.

AIM OF THE WORK

This study aimed to investigate serum levels of IL-33 in patients with Behcet's disease (BD) and their relationship to disease activity and clinical manifestations. Thirty patients with BD were enrolled and subjected to assessment of disease activity according to Behcet's Disease Current Activity Form (BDCAF) score. Serum IL-33 levels were determined using Enzyme-Linked-Immunosorbent Assay (ELISA). Thirty age and sex matched rheumatoid arthritis patients and thirty healthy volunteers were included in this study as control groups. Serum IL-33 level was 132.5±19 pg\ml, 101.2±20.1 pg\ml and 31.5±10.5 pg\ml in RA, BD and healthy control groups respectively. IL-33 was significantly higher in BD patients (101.2±20.1pg/ml) as compared to healthy controls (31.5±10.5 pg/ml) but lower than rheumatoid arthritis patients (132.5±19.1 pg/ml). Levels of IL-33 were significantly increased in BD patients with skin lesions (Erythema nodosum & Acneiform lesions) and ocular lesions (retinal vasculitis) (P<0.05), and a positive correlation was found between BDCAF score and IL-33serum levels (r=0.9, P<0.001). In conclusions, serum IL-33 level is elevated in active BD patients with skin and ocular affection and correlates with disease activity.

Serum Level of Growth Arrest-Specific 6 (Gas6) Protein and Genetic Variations in the Gas6 Gene in Patients with Type 2 Diabetes Mellitus

Growth arrest-specific protein 6 (Gas6) belongs to a family of vitamin K-dependent coagulation proteins. Plasma levels of Gas6 are associated to altered glucose tolerance. This study aimed at determining whether c.843+7G>A Gas6 polymorphism is associated with the development of type 2 diabetes mellitus. The study included 50 patients with type 2 diabetes and 40 matched controls. The Gas6 protein was measured in serum using ELISA and Gas6 gene polymorphism by polymerase chain reaction-Restriction Fragment Length Polymorphism. The GG genotype was the most prevalent in the diabetic patient. The frequency of A allele in the diabetic group was lower than the control group (P < 0.05). Serum concentrations of Gas6 were lower among type 2 diabetes patients than controls (P < 0.001). Since the AA genotype was expressed at a lower frequency in type2 diabetes patients compared to controls, a protective role for this Gas6 variant in type 2 diabetic patients may be concluded.

Interleukin-18 gene polymorphisms in systemic lupus erythematosus: relation to disease status

Systemic lupus erythematosus (SLE) is a multisystem autoimmune connective tissue disorder characterized by loss of self-tolerance causing immune-mediated tissue destruction and various clinical presentations Interleukin-18 (IL-18) is a proinflammatory cytokine that plays an important role in chronic inflammation and autoimmune disorders. This study investigates polymorphisms of the IL-18 gene in SLE patients at positions -607 and -137 of the promoter to elucidate their possible roles in the activity and severity of this disease. Fifty SLE patients and fifty unrelated healthy control group were included. AII SLE patients underwent thorough clinical examination and SLE disease activity assessment using SLEDAI. Genomic DNA was extracted from peripheral venous blood. Sequence-specific primer PCR analysis were used to genotype the DNA samples for SNP-607and SNP-137, while plasma IL-18 concentrations of patients and control subjects were measured by enzyme-linked immunosorbent assay. The frequency of SNP-607/CC genotype showed significant increase (P < 0.05), while genotype SNP-607/CA showed significant decrease (P < 0.05) in SLE patients as compared to the control group. Significantly elevated levels of plasma IL-18 were found in patients compared to controls (P < 0.001) and those with genotype CC at -607 demonstrated the highest IL-18 level (331.74 +/- 36.48 pg/mL). Serum IL-18 levels showed significant positive correlations with the ESR 1st hr. (r = 0.89), protein/creatinine ratios (r = 0.88), anti-dsDNA titers (r = 0.44) and SLEDAI scores (r = 0.91). In contrast, significant negative correlations were found with HB% r = -0.68, creatinine clearance (r = -0.87) and C3 (r = -0.81). In addition, a statistically significant association was found between IL-18 of CC -607 genotype and lupus nephritis, arthritis and immunological disorders. In conclusion, IL-18 promoter gene polymorphisms at position -607 may contribute to SLE activity and accelerate SLE development by enhancing production of IL-18 protein in SLE patients.

Finite element modeling of compression behavior of extruded polystyrene foam using X-ray tomography

Extruded polystyrene rigid foams have attracted a great attention as a superior load-bearing thermal insulation material since their implementation in building construction. One of the most common application areas of this type of thermal insulation material is under raft foundations, where the foam normally undergoes high levels of compression loads. The purpose of this research is to determine how to simulate and optimize the structural response of extruded polystyrene under compression stresses. The optimization has been achieved through investigating the relation between the foam microstructure and the global mechanical properties. The foam was first examined using X-ray tomography imaging technique to acquire some morphological information about the microstructure. The obtained morphological data of extruded polystyrene boards were then utilized to develop microstructure-based finite element models based on the so-called idealized realistic Kelvin cell. The finite element simulation was accomplished with the help of the nanoindentation technology to explore the mechanical properties of the cell wall material. The finite element models were validated by comparisons between the simulated and the experimental results. It has been found that the mechanical properties of the foam in different loading directions can be adequately simulated using the approach of the idealized realistic Kelvin cell. With the help of these models, a parameter study was carried out. This study included the effect of cell size and cell anisotropy on the mechanical response of extruded polystyrene boards under compression stresses. Charts relating between the foam microstructure characteristics and the compression behavior were generated based on the parametric study.