Avascular osteonecrosis in patients with SLE: relation to corticosteroid therapy and anticardiolipin antibodies

Predictors of Osteonecrosis in Systemic Lupus Erythematosus: A Prospective Cohort Study

OBJECTIVE

We aimed at determining the predictors of osteonecrosis (ON) in a longitudinal lupus cohort.

METHODS

Data were reviewed from the initiation of the cohort in 1987 until October 2019. In total, 2,428 patients were included in the analysis based on 224,295 person-months of follow-up. We used pooled logistic regression to assess the relationship between risk factors and rates of ON events. After identifying a set of variables related to ON incidence, we fit a final multivariable model to identify the most important risk factors for incident ON.

RESULTS

In 18,691 person-years of follow-up after cohort entry, 122 incident ON events were observed (rate = 6.5/1,000 person-years). In the multivariable analysis, African American patients were at twice the risk for ON compared to White patients. Male patients and smokers had an increased risk for ON of ~80% and 50% compared to female patients and nonsmokers, respectively. For every 10-year increase in the age at diagnosis, there was a 20% reduced risk for ON. Patients diagnosed after the 1990s had a 50% reduced risk of ON compared to those diagnosed before the 1990s. A highest daily dosage of prednisone of 40 mg or higher, even when administered for a month or less, significantly increased the risk of ON. Use of pulse methylprednisolone or intramuscular triamcinolone was not associated with an increased risk of ON.

CONCLUSION

African American patients with systemic lupus erythematosus are at double the risk of experiencing ON compared to White patients. Oral prednisone at 20-39 mg for more than 1 month, or 40 mg daily for even 1 month, at any point in the disease course, remained the most important glucocorticoid predictor of ON.

Glucocorticoid-induced osteonecrosis in systemic lupus erythematosus patients

Osteonecrosis (ON) is a complex and multifactorial complication of systemic lupus erythematosus (SLE). ON is a devastating condition that causes severe pain and compromises the quality of life. The prevalence of ON in SLE patients is variable, ranging from 1.7% to 52%. However, the pathophysiology and risk factors for ON in patients with SLE have not yet been fully determined. Several mechanisms for SLE patients' propensity to develop ON have been proposed. Glucocorticoid is a widely used therapeutic option for SLE patients and high-dose glucocorticoid therapy in SLE patients is strongly associated with the development of ON. Although the hips and knees are the most commonly affected areas, it may be present at multiple anatomical locations. Clinically, ON often remains undetected until patients feel discomfort and pain at specific sites at which point the process of bone death is already advanced. However, strategies for prevention and options for treatment are limited. Here, we review the epidemiology, risk factors, diagnosis, and treatment options for glucocorticoid-induced ON, with a specific focus on patients with SLE.

Risk of osteonecrosis in systemic lupus erythematosus: An 11-year Chinese single-center cohort study

OBJECTIVE

Osteonecrosis (ON), which can lead to physical disability, is a common complication of systemic lupus erythematosus (SLE). The purpose of this study was to determine the prevalence of ON and identify possible risk factors in Chinese SLE patients.

METHODS

SLE patients who fulfilled the 1997 American College of Rheumatology SLE classification criteria were recruited from the Peking Union Medical College Hospital. The chi-square test (χ² test) and multivariate regression analyses were used to evaluate risk factors. The Cox proportional-hazards model was used to construct the survival curves and estimate the simultaneous effects of prognostic factors on survival.

RESULTS

We consecutively enrolled 1,158 patients, of which 88 patients (7.6%) developed ON. Among ON patients, 57.1% of patients had isolated femoral head necrosis and 42.9% had multiple joint involvement. The mean age of ON patients (24.62 ± 8.89 years) was significantly younger than SLE patients without ON (27.23 ± 10.16 years, p = 0.09). The ON group presented with a much longer disease course (10.68 ± 5.97 years, p < 0.001) and increased incidence of arthritis, kidney, and central nervous system (CNS) involvement (65.9% [p < 0.05], 57.6% [p < 0.05], and 16.5% [p < 0.05], respectively, in the ON group). ON patients were more likely to be treated with glucocorticoid (GC) and to receive a high dose of prednisolone at the initial stage of SLE (p < 0.05). The percentage of patients who received hydroxychloroquine was much higher in the control group (p < 0.001). Cox regression analysis suggested that CNS involvement and GC therapy were two independent risk factors for ON in SLE patients. The presence of anti-phospholipid antibodies (aPLs) was a risk factor for multiple joint necrosis (odds ratio: 6.28, p = 0.009).

CONCLUSIONS

ON remains a serious and irreversible complication in SLE. In addition to glucocorticoid therapy, we found that CNS system involvement was a risk factor for ON, while the administration of hydroxychloroquine was a protective factor. The clinical characteristics of multiple site ON patients were distinct from isolated femoral head necrosis patients. The presence of aPLs was a risk factor for multiple site osteonecrosis.

Antiphospholipid antibodies and osteonecrosis in systemic lupus erythematosus: a meta-analysis

Objectives: The present meta-analysis aimed to assess the relationship between antiphospholipid antibodies (aPLs) or antiphospholipid antibody syndrome (APS) and the incidence of osteonecrosis (ON) in systemic lupus erythematosus (SLE) patients.Methods: MEDLINE/Pubmed, EMBASE, Web of science, the Chinese Biomedical Literature Database (CBM), the Wan-Fang Database, and the China National Knowledge Infrastructure (CNKI) were searched from their inception up until 26 December 2020. Studies in English were included. Case-control studies and cohort studies were included. Studies pertaining to the link between aPLs or APS and ON patients were slated for inclusion in the current analysis.Results: Twenty-two studies involving a total of 3054 SLE patients were included. The positivities of anticardiolipin antibody (ACL), IgG ACL, IgM ACL, LA and APS in SLE is not associated with ON. One study showed that IgG or IgM β2GP1 had no association with ON. No publication bias was detected. The quality of this evidence was low because of the high risk of bias across studies, and therefore robust inferences cannot be made.Conclusion: SLE patients demonstrated a weak association between aPLs and ON. The nature of the association between aPLs and ON in SLE needs to be investigated in-depth in future research.

Clinical profile of osteonecrosis in systemic lupus erythematosus - Experience from a tertiary care centre in South India

Introduction:

Osteonecrosis or Avascular necrosis of bone (AVN) is a well recognized complication of systemic lupus erythematosus (SLE) leading to significant morbidity.

Methods:

We did a cross sectional descriptive study in cohort of SLE patients, on regular follow-up at our Rheumatology OPD over a period of 5 years from 2012 to 2017.

Results:

Of the total 415 SLE, 5.1% (n = 21) patients were diagnosed to have osteonecrosis. The mean age was 32.8 ± 7.6 years. Male: female were 1:4.2. Mean time interval between the onset of SLE and diagnosis of osteonecrosis was 4.1 ± 2.7 years. Pain (100%) was the most common presenting symptom followed by limping gait (42.8%). Most common site affected by osteonecrosis was femoral head (80.9%) (n = 17). 14.3% (n = 3) had multifocal involvement. The most common systemic involvement was musculoskeletal system (80.9%). In total 28.5% had secondary antiphospholipid syndrome. Mean SLEDAI-2K at the time of diagnosis of osteonecrosis was 5.3 ± 2.9. Hypertension 19%, hypothyroidism 9.5%, osteoporosis 24%, and chronic HCV infection 4.7% were the associated comorbidities. The most common stage by imaging at diagnosis was stage IV (38%), followed by 24% stage V, 19% stage III and 9.5% stage II and 9.5% stage VI. Medical management include bisphosphonates (100%), statins (90.4%) and anticoagulant therapy (28.5%), while 9.5% received core decompression surgery and 14.3% underwent total hip replacement. The mean daily dose of prednisolone at diagnosis of osteonecrosis was 8.5mg (range 5–20mg).

Conclusion:

This study described the prevalence and epidemiology of osteonecrosis in our cohort of SLE patients.

Osteonecrosis of Femoral Head, An Overlooked Long-Term Complication after Paraquat Intoxication: A Retrospective Cohort Study

With increasing numbers of patients surviving acute intoxication phase, long-term complication after paraquat intoxication is a topic worth exploring, such as osteonecrosis (ON) of femoral head. We reviewed 86 paraquat-intoxicated survivors between 2000 and 2012 in Chang Gung Memorial Hospital, a 3700-bed tertiary hospital in Taiwan. With all the patients underwent same detoxification protocol in the acute stage, 17.4% of paraquat poisoning survivors developed ON of femoral head requiring surgery during follow up. Most of ON episodes occurred within 2 to 4 years after paraquat intoxication and then plateau after 6 years. ON patients exhibited higher SOFA scores than non-ON patients (2.80 ± 2.14 vs. 1.76 ± 1.52, p = 0.028). Furthermore, AKIN scores are also higher in the ON patients than non-ON patients (0.87 ± 1.13 vs. 0.38 ± 0.74, p = 0.040). Multivariate logistic regression showed higher AKIN score and higher partial pressure of carbon dioxide in the blood 48 hours after admission significantly predicted ON of femoral head after paraquat intoxication (p = 0.002 and p = 0.006 respectively). Larger studies with longer follow-up durations are warranted to confirm our finding.

Osteonecrosis in individuals with systemic lupus erythematosus: A predictive model

OBJECTIVE

This work attempts to provide a model to predict the development of osteonecrosis (ON) in individuals with systemic lupus erythematosus (SLE) using pharmacological, demographic, and psychoactive factors.

METHOD

A review of the literature was conducted to construct a survey administered across Chile to individuals with SLE during a period of three weeks. This work used a sample size of 46 de-identified data records. Two Bayesian logistic regression models were created, with non-informative prior and informative prior distributions, and a random forest model was done for comparison. All models were cross-validated.

RESULTS

The significant variables used were mean corticosteroids per day (mg) and tobacco use. The random forest model provided good accuracy and sensitivity, but low specificity. Bayesian logistic regression with prior information increased the specificity.

CONCLUSIONS

This work determined that the use of corticosteroids and tobacco are significant variables to predict ON. Using prior information provides good accuracy, specificity, and sensitivity to the prediction. Further studies need to be conducted to validate the model using a testing set.

Avascular necrosis less frequently found in systemic lupus erythematosus patients with the use of alternate day corticosteroid

Background/aim

Avascular necrosis (AVN) is the death of bone due to compromise of blood flow. The etiology of AVN is multifactorial; corticosteroid usage is the second most significant factor after trauma, and systemic lupus erythematosus (SLE) is the most common underlying disease. The objective of this study was to assess the factors of AVN in SLE patients.

Materials and methods

The study included 127 patients with SLE who fulfilled 1997 American College of Rheumatology (ACR) revised criteria. Demographic data, age at SLE diagnosis, disease duration, disease activity, body mass index, clinical findings, antiphospholipid syndrome, steroid usage, dose and duration, comorbid diseases, and smoking history were recorded.

Results

AVN was found in 11 of 127 (8.7%) SLE patients. Hyperlipidemia (P < 0.001), cushingoid body habitus (P < 0.001), and proteinuria (P = 0.013) were found at higher rates in the AVN group. All of the 11 AVN cases had osteoporosis (P < 0.02). In multivariate regression analysis, daily steroid usage was the only factor for development of AVN in SLE.

Conclusion

The hypothesis of our study was that an alternate day steroid regimen may decrease AVN frequency in SLE patients.

Monitoring of Osteonecrosis in Systemic Lupus Erythematosus: A Systematic Review and Metaanalysis

Objective.

Nontraumatic osteonecrosis (ON) is a well-recognized complication causing disability and affecting quality of life in patients with systemic lupus erythematosus (SLE). The aim of this study was to identify the risk factors for ON, and to identify the minimal investigation(s) needed to optimally monitor the risk of ON in patients with SLE.

Methods.

A systematic review was conducted using MEDLINE and EMBASE. These databases were searched up to January 2016 using the Medical Subject Heading (MeSH) terms “Osteonecrosis,” “Systemic lupus erythematosus,” and synonymous text words. Randomized controlled trials, case control, cohort, and cross-sectional studies were included. Risk factors for ON in patients with SLE were compiled. The quality of each study was assessed using the Newcastle-Ottawa scale for nonrandomized studies. The quality of evidence of each risk factor was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation method.

Results.

Of the 545 references yielded, 50 met inclusion criteria. Corticosteroid (CS) use may be strongly associated with ON in patients with SLE. Other clinical variables were moderately associated, including hypertension, serositis, renal disease, vasculitis, arthritis, and central nervous system disease. However, the evidence was low to very low in quality.

Conclusion.

Based on the best evidence available, CS use may be strongly associated with ON in patients with SLE. Results of this review were considered in the development of recommendations for the diagnosis and monitoring of patients with SLE in Canada and will guide clinicians in their assessment of these patients.

Synergistic effect of cumulative corticosteroid dose and immunosuppressants on avascular necrosis in patients with systemic lupus erythematosus

Objectives

Avascular necrosis (AVN) is one of the most common causes of organ damage in patients with systemic lupus erythematosus (SLE) and often causes serious physical disability. The aims of this study were to investigate clinical risk factors associated with symptomatic AVN and to analyze their synergistic effects in a large SLE cohort in Korea.

Methods

Patients with SLE were enrolled and followed from 1998 to 2014 in the Hanyang BAE Lupus cohort, and damage was measured annually according to the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). AVN was confirmed by imaging study if patients had symptoms. To determine risk factors for AVN, clinical, laboratory and therapeutic variables were analyzed by logistic regression. Relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy index (S) were calculated to measure interactions between significant variables.

Results

Among 1219 SLE patients, symptomatic AVN was the most common type of musculoskeletal damage (10.8%, n = 132). SLE patients with AVN showed an earlier onset age, demonstrated AVN more commonly in conjunction with certain other clinical manifestations such as renal and neuropsychiatric disorders, and received significantly higher total cumulative corticosteroid dose and immunosuppressive agents than did patients without AVN. However, in multivariable analysis, only two variables including use of a cumulative corticosteroid dose greater than 20 g (odds ratio (OR) 3.62, p = 0.015) and use of immunosuppressants including cyclophosphamide or mycophenolate mofetil (OR 4.51, p < 0.001) remained as significant risk factors for AVN. Patients with cumulative corticosteroid dose > 20 g and immunosuppressant use had a 15.44-fold increased risk for AVN, compared with patients without these risk factors ( p < 0.001). RERI, AP and S, which define the strength of interactions between two risk factors, were 9.01 (95% confidence interval (CI) 1.30–16.73), 0.58 (95% CI 0.36–0.81) and 2.66 (95% CI 1.42–4.99), respectively, supporting the presence of synergistic interactions in the development of symptomatic AVN in our Korean lupus cohort.

Conclusions

An individual risk assessment for AVN development should be made prior to and during treatment for SLE, especially in patients with high-dose corticosteroid and immunosuppressant use regardless of clinical manifestations and disease activity.

Time trend and risk factors of avascular bone necrosis in patients with systemic lupus erythematosus

Objectives

The objective of this paper is to study the time trend and risk factors of avascular bone necrosis (AVN) in patients with systemic lupus erythematosus (SLE).

Methods

Between 1999 and 2014, patients who fulfilled the ACR criteria for SLE and developed symptomatic AVN were identified from our cohort database and compared with those without AVN, matched for age, sex and SLE duration. The standardized incidence ratios (SIRs) of AVN in different SLE age groups were calculated from data derived from our hospital registry and population census. Risk factors for AVN were studied by logistic regression, adjusted by a propensity score for ever use of high-dose glucocorticoids (GCs).

Results

Fifty-five SLE patients with AVN and 220 SLE patients without AVN were studied. There were 104 AVN sites involved, with the hips being most commonly affected (82%). The point prevalence of AVN in our SLE cohort was 7.4%. The SIRs of AVN in our SLE patients were 131 (86.6–199; p < 0.001) and 56.0 (34.3–91.4; p < 0.001), respectively, in the periods 1995–2004 and 2005–2014. In both decades, the age-stratified SIR was highest in the youngest age group (<19 years). AVN patients were more likely to be treated with GCs and had received a significantly higher cumulative dose of prednisolone since SLE diagnosis (16.5 vs 10.7 grams; p = 0.001). The SLE damage score (excluding AVN) was also significantly higher in AVN than non-AVN patients (2.5 vs 0.4; p < 0.001). Logistic regression revealed that preceding septic arthritis of the involved joint (odds ratio (OR) 17.7 (1.5–205); p = 0.02), cushingoid body habitus (OR 2.4 (1.1–5.2); p = 0.04), LDL cholesterol level (OR 1.4 (1.0–1.9); p = 0.04), maximum daily dose of prednisolone (OR 6.4 (1.2–33.3); p = 0.03) and cumulative dose of prednisolone received in the first six months of the first lupus flare (OR 1.3 (1.0–1.8); p = 0.046) were independently associated with AVN.

Conclusions

AVN is prevalent in SLE, particularly in younger patients. The use of GCs remains the strongest independent risk factor. A trend of reduction in the SIR of AVN in our SLE patients is observed over the past two decades.

Orthopaedic manifestations of the antiphospholipid (Hughes) syndrome

The antiphospholipid (Hughes) syndrome (APS), is characterized by arterial and/or venous thrombosis and pregnancy morbidity in association with antiphospholipid antibodies (aPL). Since its classical description 21 years ago, the clinical spectrum of Hughes syndrome has embraced the realms of obstetrics, nephrology, cardiology, neurology, gastroenterology and now, possibly orthopaedics. This is not surprising, given that this disease can affect virtually any organ system and blood vessel of any size and nature. Just as venous thrombosis may affect limbs and internal organs, arterial thrombosis has been shown to affect organs such as the brain, eye, heart, kidney, liver and may also involve the skeleton. In this review, the skeletal aspects of Hughes syndrome, postulated pathogenesis and possible implications of anticoagulation will be discussed. Finally, the approach to APS patients undergoing orthopaedic surgery shall also be outlined.

Disease activity as a major risk factor for osteonecrosis in early systemic lupus erythematosus

This study Identifies the possible risk factors for osteonecrosis (ON) in a homogenous group of early system lupus erythematosus (SLE). Forty-six consecutive SLE patients (<5 years duration) followed at the Lupus Clinic, were enrolled between 2004 and 2005. An extensive clinical and laboratory evaluation using a standard electronic protocol established since 1999, including osteonecrosis symptoms and appropriate magnetic resonance imaging (MRI), were carried out at 1—6 months intervals. All other asymptomatic for osteonecrosis patients at study entry underwent MRI. ON confirmed by MRI was found in 10 of 46 patients (22%). Age, disease duration, clinical vascular features, frequency of thrombophilia and hypofibrinolysis factors and the lipoprotein profile were comparable in patients with and without osteonecrosis ( P > 0.05). Remarkably, the frequency of patients with system lupus erythematosus disease activity index (SLEDAI) ≥8 in the previous year of osteonecrosis clinical diagnosis was significantly higher when compared to patients without this manifestation (60.0% versus 19.4%, P = 0.011), supported by the higher glucocorticoid cumulative dose in the same period ( P = 0.045). In contrast, these two parameters evaluated in 13th—24th months preceding osteonecrosis diagnosis were similar in patients with and without osteonecrosis ( P > 0.05). In the logistic regression analysis only SLEDAI remained as an independent risk factor for ON (OR = 6.78, CI = 1.05—43.55, P = 0.04). Disease activity in the previous year of ON clinical diagnosis is the main predictor factor for the development of this complication in early SLE. Lupus (2007) 16, 239—244.

Review: Measuring permanent damage in pediatric systemic lupus erythematosus

The survival rates in pediatric systemic lupus erythematosus (pSLE) have improved greatly over recent decades. Increased life expectancy has meant that more children are growing up with the consequences of chronic disease and prolonged therapy. Assessing complications of disease and its therapy becomes an important outcome measure by which to evaluate our therapeutic interventions and appraise quality of life.

In this paper we review the development of the Systemic Lupus International Collaborative Clinics (SLICC)/American College of Rheumatology (ACR) Damage Index (SDI) and its application to the pSLE population. We examine the profile of damage in pSLE as identified by the SDI. However we also critically appraise its application and identify potential limitations in the SDI as a measure of permanent disease damage in children. In this paper we put forth suggestions for additional domains addressing pediatric specific issues such as decreased final height and delayed puberty. We also suggest modifications to domains of gonadal failure, diabetes mellitus, cognitive impairment and osteonecrosis in the SDI to make it more reflective of the damage phenomenon observed in pediatrics. Lupus (2007) 16: 657—662.

Musculoskeletal manifestations of the antiphospholipid syndrome

The scope of clinical and laboratory manifestations of the antiphospholipid syndrome (APS) has increased dramatically since its discovery in 1983, where any organ system can be involved. Musculoskeletal complications are consistently reported in APS patients, not only causing morbidity and mortality, but also affecting their quality of life. We reviewed all English papers on APS involvement in the musculoskeletal system using Google Scholar and Pubmed; all reports are summarized in a table in this review. The spectrum of manifestations includes arthralgia/arthritis, avascular necrosis of bone, bone marrow necrosis, complex regional pain syndrome type-1, muscle infarction, non-traumatic fractures, and osteoporosis. Some of these manifestations were reported in good quality studies, some of which showed an association between aPL-positivity and the occurrence of these manifestations, while others were merely described in case reports.

Risk Factors for Symptomatic Avascular Necrosis in Childhood-onset Systemic Lupus Erythematosus

Objective.

To examine the frequency and risk factors for symptomatic avascular necrosis (AVN) in childhood-onset systemic lupus erythematosus (cSLE).

Methods.

A single-center, nested, matched, case-control design was used. There were 617 patients with cSLE followed at the Hospital for Sick Children (SickKids) Lupus Clinic between July 1982 and June 2013 included in the study. The AVN cohort consisted of 37 patients identified with clinical findings of symptomatic AVN and diagnosis was confirmed by 1 or more imaging modalities. Three controls were matched to each patient with AVN by date and age at diagnosis. Baseline clinical, laboratory, and treatment characteristics were compared between patients with AVN and controls by univariable analyses and if statistically significant, were included in a multivariable logistic regression model.

Results.

A total of 37/617 patients (6%) developed symptomatic AVN in 91 joints during followup at SickKids. The mean duration to disease was 2.3 years. The hip was the most commonly involved joint (26/37, 70%). Compared with the matched non-AVN cohort, patients with AVN had a higher incidence of central nervous system (CNS) involvement and nephritis, required greater cumulative prednisone (PRED) from cSLE diagnosis to AVN, received a greater maximal daily PRED dose, and had more frequent use of pulse methylprednisolone therapy. Multivariable regression analysis confirmed major organ involvement (CNS disease and/or nephritis) and maximal daily PRED dose as significant predictors of symptomatic AVN development.

Conclusion.

Patients with cSLE with severe organ involvement including nephritis and CNS disease and higher maximal daily dose of PRED are more likely to develop symptomatic AVN.

High-Dose Corticosteroid Use and Risk of Hip Osteonecrosis: Meta-Analysis and Systematic Literature Review

The effect of varying corticosteroid regimens on hip osteonecrosis incidence remains unclear. We performed a meta-analysis and systematic literature review to determine osteonecrosis occurrences in patients taking corticosteroids at varying mean and cumulative doses and treatment durations, and whether medical diagnoses affected osteonecrosis incidence. Fifty-seven studies (23,561 patients) were reviewed. Regression analysis determined significance between corticosteroid usage and osteonecrosis incidence. Osteonecrosis incidence was 6.7% with corticosteroid treatment of >2 g (prednisone-equivalent). Systemic lupus erythematosus patients had positive correlations between dose and osteonecrosis incidence. Each 10 mg/d increase was associated with a 3.6% increase in osteonecrosis rate, and >20 mg/d resulted in a higher osteonecrosis incidence. Clinicians must be wary of osteonecrosis in patients on high corticosteroid regimens, particularly in systematic lupus erythematosus.

Antileukemic Efficacy of Continuous vs Discontinuous Dexamethasone in Murine Models of Acute Lymphoblastic Leukemia

Osteonecrosis is one of the most common, serious, toxicities resulting from the treatment of acute lymphoblastic leukemia. In recent years, pediatric acute lymphoblastic leukemia clinical trials have used discontinuous rather than continuous dosing of dexamethasone in an effort to reduce the incidence of osteonecrosis. However, it is not known whether discontinuous dosing would compromise antileukemic efficacy of glucocorticoids. Therefore, we tested the efficacy of discontinuous dexamethasone against continuous dexamethasone in murine models bearing human acute lymphoblastic leukemia xenografts (n = 8 patient samples) or murine BCR-ABL+ acute lymphoblastic leukemia. Plasma dexamethasone concentrations (7.9 to 212 nM) were similar to those achieved in children with acute lymphoblastic leukemia using conventional dosages. The median leukemia-free survival ranged from 16 to 59 days; dexamethasone prolonged survival from a median of 4 to 129 days in all seven dexamethasone-sensitive acute lymphoblastic leukemias. In the majority of cases (7 of 8 xenografts and the murine BCR-ABL model) we demonstrated equal efficacy of the two dexamethasone dosing regimens; whereas for one acute lymphoblastic leukemia sample, the discontinuous regimen yielded inferior antileukemic efficacy (log-rank p = 0.002). Our results support the clinical practice of using discontinuous rather than continuous dexamethasone dosing in patients with acute lymphoblastic leukemia.

Osteonecrosis in systemic lupus erythematosus

OBJECTIVES

To define the proportion of osteonecrosis (ON) in our patient population with lupus and to identify factors associated with the development of ON in systemic lupus erythematosus, as well as to carry out a descriptive analysis of ON cases.

MATERIALS AND METHODS

Observational retrospective study of 158 patients with SLE (ACR 1982 criteria). Demographic and laboratory data, clinical manifestations, SLICC, SLEDAI, cytotoxic and steroid treatments were compared. In patients with ON, we analyzed time of disease progression and age at ON diagnosis, form of presentation, joints involved, diagnostic methods, Ficat-Arlet classification, and treatment. To compare the means, t-test or Mann-Whitney's test were employed and the cHi-2 test or Fisher's exact test, as appropriate, were used to measure the equality of proportions.

RESULTS

ON was present in 15 out 158 patients (9.5%), 13 women and 2 men, with a mean age of 30 (r: 16-66) at diagnosis and 35 months of evolution until diagnosis (r: 1-195). Among the 15 patients, 34 joints presented ON, 23 were symptomatic and 22 were diagnosed by magnetic resonance images. Twenty-six occurred in hips (24 bilateral), 4 in knees and 4 in shoulders. In 13 patients, ON involved 2 or more joints. At onset, 28 joints were in stage i-ii, one in stage iii and 5 had no data and; in the end, 14 were in stage iii-iv, 5 in stage i-ii and 15 had no data. Twenty-nine underwent conservative treatment with rest and 8 hips required joint replacement. ON progression was associated with Cushing's syndrome (P=0.014) OR 4.16 (95% CI 1.4-12.6) and 2nd year SLICC (P=0.042). No relation with clinical manifestations, lab results, cytotoxic treatment, steroid treatment (total accumulated dose, mean daily dose and duration) metilprednisolone pulses, nor activity was found. All patients with ON received antimalarials, in contrast to 77% of those without ON.

CONCLUSIONS

The proportion of ON was 9.5%, mainly in women, 76% in hips (26) and 92% bilaterally. They were associated significantly with Cushing's syndrome and accumulated damage at second year.

Prevalence, incidence, and associated factors of avascular necrosis in Korean patients with systemic lupus erythematosus: a nationwide epidemiologic study

Avascular necrosis (AVN) is one of the most frequent types of organ damage in systemic lupus erythematosus (SLE). However, little is currently known about the epidemiology of AVN in SLE patients. The aim of this study was to estimate the prevalence and incidence of AVN in Korean patients with SLE based on National Health Insurance (NHI) claims data and to determine the risk factors for AVN among SLE patients. This study was conducted using the 2006-2010 data of 25,358 SLE patients from the NHI program. AVN cases were defined as those with at least one diagnosis of AVN. The prevalence was calculated by dividing the number of AVN cases by the number of SLE cases in the same year. The annual incidence was calculated by dividing the number of incident AVN cases by the number of SLE-prevalent cases not previously diagnosed with AVN. Patients who developed AVN in 2008-2010 were compared with SLE patients who did not develop AVN to identify any risk factors. The prevalence of AVN among SLE patients (2006-2010) was 31.5-34.2 per 1,000 persons and was similar in all the years studied. The incidence per 1,000 persons of AVN among SLE patients was 8.6 [95 % confidence interval (95 % CI) 6.9-10.3] in 2008, 9.8 (95 % CI 8.0-11.6) in 2009, and 8.4 (95 % CI 6.8-10.0) in 2010. Regression analysis indicated that taking an oral corticosteroid [odds ratio (OR) 2.12, 95 % CI 1.39-3.23] or an intravenous corticosteroid (OR 1.5, 95 % CI 1.2-1.89) was significantly associated with AVN. In addition, AVN was associated with use of immunosuppressive agents (OR 2.12, 95 % CI 1.66-2.72), hydroxychloroquine (OR 1.4, 95 % CI 1.09-1.81), and lipid-lowering agents (OR 1.78, 95 % CI 1.24-2.57) among the prescribed medications, and with hypertension (OR 1.39, 95 % CI 1.08-1.79) among the comorbidities. The prevalence and incidence of AVN among SLE patients, which were 31.5-34.2 and 8.4-9.8 per 1,000 persons, respectively, may be representative of the entire population of symptomatic AVN patients with SLE in Korea. AVN is associated with the use of corticosteroids, immunosuppressants, hydroxychloroquine, lipid-lowering agents, and with hypertension. Studies of large, prospective cohorts are needed to confirm these results.

Aseptic necrosis at multiple localisations in a lupus patient with lymphoma

Avascular or aseptic necrosis is a well-defined entity leading to the degradation of cellular elements of the bone. The pathogenesis of osteonecrosis (ON) is still unknown. There are two main types of ON: traumatic or non-traumatic. Several clinical entities could associate with ON, systemic diseases, environmental factors, pregnancy, systemic autoimmune or rheumatic diseases, thrombophilia, corticosteroid therapy, cytotoxic dugs, infections, metabolic and hematologic diseases, etc. Corticosteroids (CS) are still the most frequently used therapeutic options in the early phase and during flares of these diseases. Inflammatory cytokines and antibodies have been described to participate in the pathogenesis of ON. The infiltrative disorders of the bone marrow could also contribute to the development of ON. Hereby, we describe a female patient with NHL followed by SLE in whom ON has developed at least in two localisations. Lupus flare, long-term CS therapy, lymphoma relapse or the presence of antiphospholipid antibodies were excluded. Although the bi-localised ON could be contributed to immunologic factors or trauma, the exact aetiology in this case could not be elucidated.

Glucocorticoid-induced avascular bone necrosis: diagnosis and management

Glucocorticoid use is one of the most important causes of avascular bone necrosis (AVN). The pathogenesis of glucocorticoid-induced AVN is not fully understood but postulated mechanisms include fat hypertrophy, fat emboli and intravascular coagulation that cause impedance of blood supply to the bones. Data regarding the relationship between AVN and dosage, route of administration and treatment duration of glucocorticoids are conflicting, with some studies demonstrating the cumulative dose of glucocorticoid being the most important determining factor. Early recognition of this complication is essential as the prognosis is affected by the stage of the disease. Currently, there is no consensus on whether universal screening of asymptomatic AVN should be performed for long-term glucocorticoid users. A high index of suspicion should be exhibited for bone and joint pain at typical sites. Magnetic resonance imaging (MRI) or bone scintigraphy is more sensitive than plain radiograph for diagnosing early-stage AVN. Conservative management of AVN includes rest and reduction of weight bearing. Minimization of glucocorticoid dose or a complete withdrawal of the drug should be considered if the underlying conditions allow. The efficacy of bisphosphonates in reducing the rate of collapse of femoral head in AVN is controversial. Surgical therapy of AVN includes core decompression, osteotomy, bone grafting and joint replacement. Recent advances in the treatment of AVN include the use of tantalum rod and the development of more wear resistant bearing surface in hip arthroplasty.

Osteonecrosis in systemic lupus erythematosus: an early, frequent, and not always symptomatic complication

Osteonecrosis may complicate the course of systemic lupus erythematosus and may contemporaneously affect multiple joints. The major risk factor associated with the development of osteonecrosis is the use of glucocorticoid at high doses. Recent studies using serial MRI, which represents the “gold standard” for the early detection of osteonecrosis, yielded some interesting findings about the natural history of this clinical entity. Osteonecrosis in the majority of the cases is asymptomatic and occurs early in the course of the disease. Its later occurrence is associated with lupus flare that requires the increase of corticosteroid dose. The optimal treatment of osteonecrosis is controversial. In case of silent osteonecrosis involving a small area conservative strategy is usually adequate. When lesions are symptomatic surgical treatment as core decompression or free vascularized fibular grafting is required; extracorporeal shockwave treatment may represent an alternative therapeutic approach. When the lesion has a medium-large dimension or involves a weight-bearing area bone collapse is a common complication requiring total joint replacement. Coadministration of bisphosphonate or warfarin with high doses of corticosteroid might be a promising preventive strategy of osteonecrosis.

Steroid induced osteonecrosis: An analysis of steroid dosing risk

Osteonecrosis is a serious condition involving bone destruction that frequently requires surgical treatment to rebuild the joint. While there is an abundance of literature documenting corticosteroid related osteonecrosis, there is no consensus as to the relative risk of osteonecrosis after administration of steroids via parenteral, oral, topical, inhaled and other routes. This risk is an important prognostic indicator because identification and conservative intervention can potentially reduce morbidity associated with aggressive surgical treatment of osteonecrosis. This paper provides insight into establishing guidelines related to the risk of developing osteonecrosis as a result of corticosteroid use. Case studies, retrospective studies and prospective studies in humans on different corticosteroids and varied dosages were assessed. Most cases of osteonecrosis are secondary to systemically administered corticosteroids and/or high dose daily therapy, particularly in patients with underlying comorbidities including connective tissue diseases, hyperlipidemia, or previous trauma. Previous case reports of osteonecrosis related to inhaled or topical use of steroids are complicated by the fact that in the great majority of cases, the patients are also treated with systemic steroids prior to the development of osteonecrosis. Based on the literature, a set of recommendations regarding the risk of osteonecrosis in patients on steroids was formulated.

Factors associated with osteonecrosis in Thai lupus patients: a case control study

OBJECTIVE

To identify associated factors for the development of osteonecrosis of a femoral head (ON) in patients with systemic lupus erythematosus (SLE).

METHODS

We conducted a retrospective nested case-control study from SLE patients who attended the Rheumatology Clinic at Phramongkutklao Hospital from 1992-2008. Cases were defined as SLE patients, who had clinically apparent ON (confirmed by plain radiographs or magnetic resonance imaging). For each case, a control was selected and matched to the case by age and disease duration. The main outcome measure was the odds ratio (OR) of ON among SLE patients. The clinical and laboratory variables thought to be risk factors of ON variables were compared between patients who did and did not develop ON. Significant and clinically relevant variables were then examined by a stepwise logistic regression model.

RESULTS

Of 186 SLE patients, we identified 41 patients who developed ON during the course of follow-up. Twenty patients were available for data analysis. From the univariate analysis, incidence of renal involvement and the use of steroids (recorded as evidenced by maximum and mean daily prednisolone dose) were significantly higher in the ON group than in controls. The use of antimalarials was significantly lower in patients with ON than in controls. No difference in disease activity, lipid profiles or anticardiolipin antibody was found between groups. In the logistic regression, the presence of renal involvement remained as a positive associated factor for ON (OR = 7.80, CI = 1.249-48.748, P = 0.028) and the use of antimalarial drugs was a negative associated factor for ON (OR = 0.09, CI = 0.009-0.961, P = 0.046).

CONCLUSION

The presence of renal involvement was associated with ON and the antimalarial use may have a protective effect for ON in Thai patients with SLE. The findings from this study further support the use of antimalarial drugs in SLE patients.

Symptomatic, steroid-induced, multifocal diaphyseal osteonecrosis in a patient with multiple sclerosis

There is a well-established link between the development of osteonecrosis and steroid administration. Diaphyseal osteonecrosis is rare and, when present, frequently asymptomatic and detected radiologically. We present a case of symptomatic, multifocal, diaphyseal osteonecrosis in a woman receiving pulsed corticosteroids for symptom control of multiple sclerosis (MS). She was investigated for knee pain, which could have been attributed to her primary disease, and magnetic resonance imaging (MRI) revealed bone infarcts within the femur, tibia and talus. She underwent successful intra-medullary reaming to the diaphyseal infarcts. This case highlights the importance of investigating musculoskeletal pain in patients with MS, receiving corticosteroids.

Investigation of occurrence of osteonecrosis of the femoral head after increasing corticosteroids in patients with recurring systemic lupus erythematosus

Osteonecrosis (ON) of the femoral head is known to occur commonly in cases with systemic lupus erythematosus (SLE) that received corticosteroid (CS) treatment. However, there have been no detailed reports about the onset of ON in cases with recurrence of SLE. Using MRI, we followed up 17 patients who experienced recurrence of SLE for at least 1 year at our hospital and in whom the CS dose was increased from a maintenance dose to middle to high dose to see if ON would occur. We then compared the group that developed ON and the group that did not with respect to patient characteristics, blood test results, changes in serum lipid levels, and CS dose. ON occurred in five subjects (29.4%), revealing that osteonecrosis occurs not only when CS are first administered but also in cases which the CS dose is increased for recurrence of SLE. Especially, serum cholesterol levels and its rate of increase soared rapidly soon after increasing the CS dose in the ON group as compared with the non-ON group (P < 0.05). This suggests that increased serum lipid levels might be a contributing factor to onset of ON. Moreover, SLE disease activity index 2000 (SLEDAI-2K) scores when the CS dose was increased were significantly (P < 0.05) higher in the ON group, suggesting that SLE disease activity itself is a risk factor for onset of ON.

Association of polymorphisms in the Interleukin 23 receptor gene with osteonecrosis of femoral head in Korean population

Osteonecrosis of the femoral head (ONFH) is known as death of the cellular portion of the femoral head due to an interruption in the vascular supply. The underlying pathophysiology regarding bone cell death remains uncertain. Recently, several studies have shown that autoimmune disorders were related to the development of osteonecrosis. This study investigated the genetic effects of Interleukin 23 receptor (IL23R) polymorphisms regarding the risk of ONFH. Ten SNPs were selected and genotyped in 443 ONFH patients and 273 control subjects in order to perform the genetic association analysis. It was found that polymorphisms of the IL23R gene (rs4655686, rs1569922 and rs7539625) were significantly associated with an increased risk of ONFH (P values; 0.0198-0.0447, OR; 1.30-1.49). Particularly, a stratified analysis based on etiology (alcohol, steroid or idiopathic) showed that the associations between these polymorphisms and ONFH were most significant in idiopathic ONFH patients (P values; 0.0001-0.0150, OR; 1.45-2.17). These results suggest that IL23R polymorphisms may play an important role in the development of ONFH.

Orthopedic involvement in antiphospholipid syndrome

Antiphospholipid syndrome (APS) is a common autoimmune disease, manifested by vascular thrombosis and fetal loss in the presence of antiphospholipid antibodies. Orthopedic involvement is a relatively novel and under-recognized feature of APS. In this article we review the association of primary, secondary, and catastrophic APS with diverse orthopedic conditions, including osteonecrosis in adult and pediatric patients, bone marrow necrosis, nontraumatic fractures, and some other disorders.

The role of non-corticosteroid related factors in osteonecrosis (ON) in systemic lupus erythematosus: a nested case-control study of inception patients

Several factors have been associated with the development of osteonecrosis (ON) in SLE but corticosteroid (CS) therapy has been the most consistent association. We sought to determine factors that predisposed to, or protected from, the development of ON in lupus patients when cumulative oral corticosteroid doses were matched between cases and controls, thereby removing presence of corticosteroid therapy and cumulative dose as risk factors. A nested case-control study of an inception cohort of SLE patients was used to determine the clinical, laboratory and therapeutic differences between patients who developed their first ON event and patients who did not develop ON, having matched these groups for their cumulative oral corticosteroid doses. Of the 570 patients seen within the first year after diagnosis 65 (11.4%) developed ON. None of the variables examined were found to confer additional ON risk in multivariate analysis. It appears that the major factor associated with the development of ON is corticosteroid therapy. Factors which may protect a majority of patients on corticosteroids from developing ON remain to be elucidated.

Multifocal avascular necrosis after liver transplantation: an unusual presentation of the antiphospholipid syndrome

We describe the case of a 31-year-old man who presented with an antiphospholipid syndrome (APS), which manifested as multifocal avascular necrosis (AVN) one year after orthotopic liver transplantation. The patient developed multiple AVN affecting hips, left knee, humerus and tarsal bones just after withdrawal of corticosteroid therapy. Three years later when lupus anticoagulant was detected, he began anticoagulant treatment and no further AVN episodes were observed. It is important to be aware of this clinical manifestation of APS, especially in these cases where it can be easily overlooked because of corticosteroid therapy.

Avascular necrosis of the bones: an overlooked complication of pulse steroid treatment of multiple sclerosis

The most common cause avascular osteonecrosis (AVN) is corticosteroid medication. However, the impact of pulse steroid therapy on AVN development is not known properly. We intended to investigate the effect of this therapy on AVN development in multiple sclerosis (MS) patients. MS patients without AVN, chronic alcoholism, thrombophilia, sickle cell anemia, inflammatory bowel disease, cytotoxic drug usage history participated in the study. All of the patients were ambulatory (EDSS < 4). Thirty-three MS patients who received pulse steroid therapy at least 10 g or at least 15 g during the course of the whole disease, were the treatment group and 27 MS patients who did not receive any steroid therapy were the control group. There was no statistical difference between groups for age, sex and disease duration. Bilateral femoral magnetic resonance imaging (MRI) was performed to the both groups. In the treatment group, five patients (15.5%) had AVN whilst no AVN was found in the control group. In conclusion, it is interesting to find AVN at such a high rate in the MS patients who received pulse steroid therapy without any AVN history or complaint. The neurologists have to be more careful about AVN which early diagnosis is important to prevent the complications.

Sung JJ, K. Lam CW. Steroid-induced osteonecrosis in severe acute respiratory syndrome: a retrospective analysis of biochemical markers of bone metabolism and corticosteroid therapy

Aim

We investigated the effect of massive doses of corticosteroid therapy on bone metabolism using specific biochemical markers of bone metabolism, and the prevalence of osteonecrosis in severe acute respiratory syndrome (SARS) patients at a university teaching hospital in Hong Kong.

Methods

Seventy-one patients with a clinical diagnosis of SARS were studied according to the modified World Health Organization case definition of SARS who were involved in the SARS epidemic between 10 March and 20 June 2003. The clinical diagnosis was confirmed by serological test and/ or molecular analysis. Biochemical markers of bone metabolism were analysed retrospectively using serial clotted blood samples collected from each patient during the course of hospital admission to discharge and subsequent follow-up at out-patient clinic using the arbitrary time periods: (i) Day <10; (ii) Day 28-44; (iii) Day 51-84; and (iv) Day >90 after the onset of fever. Magnetic resonance imaging of the knee and hip joints were performed post-admission to evaluate the prevalence of osteonecrosis amongst these SARS patients. Various risk factors for the development of osteonecrosis were assessed using receiver operating characteristics curve comparison with appropriate test statistics and Spearman’s coefficients of rank correlation with biochemical bone markers.

Results

Biochemical markers of bone metabolism showed significant bone resorption as evidenced by a marked increase in serum C-terminal telopeptide concentration (CTx) from Day 28-44 after the onset of fever. With tapering down of corticosteroid dosage, CTx started to return to previous baseline level from Day 51 onwards, while other bone formation markers, serum osteocalcin and bone- specific alkaline phosphatase concentrations (OC and BALP, respectively), started to increase. The latter effect was even more marked after Day >90. Seven patients developed radiological evidence of osteonecrosis. The prevalence of osteonecrosis in this cohort was 9.9%. A total corticosteroid dosage of >1900mg hydrocortisone, >2000 mg methylprednisolone, >13 340 mg hydrocortisone-equivalent corticosteroid therapy, and >18 days on corticosteroid therapy were found to be significant risk factors for the subsequent development of osteonecrosis. There were also significant positive correlations amongst various biochemical bone markers in this patient cohort.

Conclusion

Both bone resorption and formation markers were unable to predict the subsequent development of osteonecrosis. The use of high dose of hydrocortisone or methylprednisolone for an extended duration was shown to be a significant risk factor for osteonecrosis. Its prevalence in this cohort is comparable to those reported in the literature for SARS patients with high-dose corticosteroid therapy. The Day 28–44 increase in the serum CTx coincided with the timing of corticosteroid use. The Day >51 increase in serum OC and BALP coincided with the timing of corticosteroid withdrawal.

Osteoarticular Manifestations of Antiphospholipid Syndrome

In conclusion, arthralgias represent a rather common osteoarticular manifestation of primary and secondary APS, while arthritis is mainly described in SLE-related APS. Osteonecrosis is frequently described in association with aPL in patients with and without autoimmune disorders. The presence of osteonecrosis in primary APS patients in the absence of corticosteroid use suggests an association between osteonecrosis and APS. Clinicians should be aware of this possible clinical manifestation of APS, because early diagnosis may lead to early management. A systematic screening for aPL in all cases with diagnosed osteonecrosis in the absence of precipitating factors should be considered.

Percutaneous drilling for the treatment of secondary osteonecrosis of the knee

Osteonecrosis of the knee comprises two separate disorders, primary spontaneous osteonecrosis which is often a self-limiting condition and secondary osteonecrosis which is associated with risk factors and a poor prognosis. In a series of 61 knees (38 patients) we analysed secondary osteonecrosis of the knee treated by a new technique using multiple small percutaneous 3 mm drillings. Total knee replacement was avoided in 59 knees (97%) at a mean follow-up of 3 years (2 to 4). Of the 61 knees, 56 (92%) had a successful clinical outcome, defined as a Knee Society score greater than 80 points. The procedure was successful in all 24 knees with small lesions compared with 32 of 37 knees (86%) with large lesions. All the procedures were performed as day cases and there were no complications. This technique appears to have a low morbidity, relieves symptoms and delays more invasive surgery.

[Orthopedic manifestations of the antiphospholipid syndrome]

PURPOSE

The antiphospholipid syndrome (APS) is characterized by arterial and/or venous thrombosis, and pregnancy morbidity in association with antiphospholipid antibodies. Since its classical description 22 years ago, the clinical spectrum of APS has embraced the realms of obstetrics, nephrology, cardiology, neurology, gastroenterology, angiology and now, possibly orthopaedics. This is not surprising given that this disease can affect virtually any organ system and blood vessel of any size and nature. Just as venous thrombosis may affect limbs and internal organs, arterial thrombosis has been shown to affect organs such as the brain, eye, heart, kidney, liver and may also involve the skeleton.

CURRENT KNOWLEDGE AND KEY POINTS

In this review, we describe the orthopedic aspects of APS recently reported, bone metatarsal fractures, osteonecrosis and more exceptional complications, ie algodystrophy and bone marrow necrosis. We briefly discuss postulated pathogenesis and possible implications of anticoagulation.

FUTURE PROSPECTS AND PROJECTS

This data need further confirmation. They may suggest complementary physiopathologic and therapeutic implications.

Systemic lupus erythematosus in a multiethnic US cohort (LUMINA): XXIV. Cytotoxic treatment is an additional risk factor for the development of symptomatic osteonecrosis in lupus patients: results of a nested matched case-control study

BACKGROUND

Osteonecrosis is common in systemic lupus erythematosus (SLE) and often disabling. The role of glucocorticoids in its development is well known.

OBJECTIVE

To explore other possible risk factors for osteonecrosis in SLE.

METHODS

A nested matched case-control study undertaken in the context of a large, longitudinal, multiethnic lupus cohort (LUMINA), currently formed of 571 SLE patients meeting American College of Rheumatology criteria. All those developing symptomatic osteonecrosis after the diagnosis of SLE were considered cases. Two controls matched for age, disease duration, ethnicity, and centre were selected for each case. Cases and controls were compared by univariable analyses using selected variables. Variables with p<0.10 and those thought clinically relevant were entered into conditional logistic regression models including either the average dose or the highest dose of glucocorticoids, with osteonecrosis as the dependent variable.

RESULTS

32 cases were identified and 59 matched controls selected (in five cases only one control could be found). By univariable analyses, both groups were largely comparable for socioeconomic-demographic, clinical, and laboratory variables. Cases were less exposed to hydroxychloroquine (as assessed by the percentage of exposure time) (p = 0.026), used higher doses of glucocorticoids (average and highest doses) (p = 0.011 and 0.001, respectively), and received cytotoxic drugs more often (p = 0.015). In the multivariable analyses only cytotoxic drug use (both models) and the highest dose of glucocorticoids remained associated with the occurrence of osteonecrosis.

CONCLUSIONS

Cytotoxic drug use is a risk factor for the development of symptomatic osteonecrosis in SLE patients, along with glucocorticoids. No definite protective factors were identified.

Avascular Necrosis of Bone Associated With Primary Antiphospholipid Syndrome

We describe, the case of a 34-year-old mestizo Mexican woman with previous history of fetal loss, deep vein thrombosis that developed avascular necrosis (AVN) of the right knee with strong positive levels of anticardiolipin antibodies (aCL) IgG and IgM. AVN of bone in association with aCL has been seen principally in systemic lupus erythematosus patients. However, few cases have been reported of AVN as a clinical manifestation of primary antiphospholipid syndrome. A review of the association of aCL and AVN in patients with systemic lupus erythematosus, primary antiphospholipid syndrome, and idiopathic osteonecrosis is presented.

Antiphospholipid antibodies and antiphospholipid syndrome in 57 children and adolescents with systemic lupus erythematosus

The presence of antiphospholipid (aPL) antibodies and antiphospholipid syndrome (APS) was researched in 57 children and adolescents with systemic lupus erythematosus (SLE). The frequency of aPL antibodies was 75.4% (anticardiolipin 70.2% and lupus anticoagulant 29.1%). The positivity for these antibodies fluctuated during the course of the disease. No association was found between aPL antibodies and clinical or laboratory manifestations or the autoantibodies studied, nor with the activity or gravity of the SLE. APS was diagnosed in 14% of the cases (eight patients), on average three years after the diagnosis of SLE. Four patients had arterial thrombosis (stroke, three; transient ischaemic attack, one; amaurosis fugax, two; renal, one), one presented with deep vein thrombosis (DVT) and three had involvement of small calibre vessels (osteonecrosis, two; transverse myelitis, one). Recurrences were observed in three of the eight cases (37.5%), with a mean interval of 13 months between the events. The presence of APS was associated with haemolytic anaemia, leukopenia, thrombocytopenia, coagulation abnormalities, ischaemic cerebrovascular accidents, amaurosis fugax, osteonecrosis and interstitial pneumonitis. A negative association was observed between APS and the presence of anti-Ro antibodies.

Immunologic factors in the pathogenesis of osteonecrosis

Osteonecrosis is a disease in which death of cellular elements of bone occurs as a result of diminished arterial blood supply. The pathogenetic mechanisms of osteonecrosis remain unresolved. Extravascular pressure and subsequent tamponade of the arterial vessels or an intravascular thrombosis have been suggested. Immunologic factors may also play an important role. In autoimmune disorders, small vessel vasculitis or other disease-associated features, as well as antiphospholipid antibodies, have been involved in the development of osteonecrosis.

Pathogenesis and natural history of osteonecrosis

BACKGROUND AND OBJECTIVES

Osteonecrosis (avascular necrosis) is a relatively common disorder seen by both rheumatologists and orthopedic surgeons. The vast majority of cases are secondary to trauma. However, for non-traumatic cases, there often remains a diagnostic challenge in defining the cause of bone death. The goal of this article is to review data extensively in the medical literature with respect to the pathogenesis of osteonecrosis, its natural history, and treatment.

METHODS

A review of 524 studies on osteonecrosis was performed, of which 213 were selected and cited.

RESULTS

Non-traumatic osteonecrosis has been associated with corticosteroid usage, alcoholism, infections, hyperbaric events, storage disorders, marrow infiltrating diseases, coagulation defects, and some autoimmune diseases. However, a large number of idiopathic cases of osteonecrosis have been described without an obvious etiologic factor. Although corticosteroids can produce osteonecrosis, careful history is always warranted to identify other risk factors. The pathogenesis of non-traumatic osteonecrosis appears to involve vascular compromise, bone and cell death, or defective bone repair as the primary event. Our understanding of the pathogenesis of osteonecrosis is now much better defined and skeletal scintigraphy and magnetic resonance imaging have enhanced diagnosis greatly. Early detection is important because the prognosis depends on the stage and location of the lesion, although the treatment of femoral head osteonecrosis remains primarily a surgical one.

CONCLUSIONS

Osteonecrosis has been associated with a wide range of conditions. Many theories have been proposed to decipher the mechanism behind the development of osteonecrosis but none have been proven. Because osteonecrosis may affect patients with a variety of risk factors, it is important that caregivers have a heightened index of suspicion. Early detection may affect prognosis because prognosis is dependent on the stage and location of the disease. In particular, the disease should be suspected in patients with a history of steroid usage, especially in conjunction with other illnesses that predispose the patient to osteonecrosis.

RELEVANCE

A better understanding of the pathophysiology, diagnosis and treatment of osteonecrosis will help the physician determine which patients are at risk for osteonecrosis, facilitating early diagnosis and better treatment options.

Protective effect of hydroxychloroquine in systemic lupus erythematosus. Prospective long-term study of an Israeli cohort

Systemic lupus erythematosus-associated irreversible organ/system damage was previously associated with various clinical and demographic features. We analysed the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SLICC/ACR DI) in a cohort of 151 Israeli patients followed for a mean (+/- s.d.) period of 45.7 +/- 37.4 months. Mean score of SLICC/ACR DI at the first and last encounters were 0.17 +/- 64 and 1.64 +/- 2.1, respectively (P < 0.0001). Multiple logistic regression analyses disclosed a statistically significant positive correlation with corticosteroid and cyclophosphamide therapy. Hydroxychloroquine therapy was significantly associated with lower SLICC/ACR DI. Although the size of our study group did not allow us to find specific organs/systems which were associated with the protective effect of hydroxychloroquine, we suggest this is due to the antiatherogenic effects attributed to antimalarial therapy in SLE.

Relationship between systemic corticosteroids and osteonecrosis

Numerous reports describe osteonecrosis after oral corticosteroid therapy. It is still uncertain if corticosteroid treatment alone or in combination with other factors leads to the development of this condition. The literature presents controversial clinical and experimental data. The most affected site for osteonecrosis is the femoral head and therefore our considerations are concentrated at this site. Oral corticosteroids are commonly used in dermatology, especially in the treatment of connective tissue diseases and hypersensitive diseases. This clinical review evaluates the relationship between and the onset of femoral head necrosis. Although osteonecrosis of the femoral head can be caused by various conditions such as trauma, excess alcohol and hemoglobinopathies, studies indicate that treatment with corticosteroids is the most common cause of the condition. There is some controversy on the role of underlying disease and total corticosteroid dose administered, in the development of osteonecrosis of the femoral head. MRI scans are used to establish an early diagnosis. There are several surgical and nonsurgical options for disease management, dependent on the stage of disease, the age of the patient and other risk factors. In general, the risk for osteonecrosis is considered to be low under oral corticosteroid therapy. So far, no data can establish a direct relationship, but data still strongly suggest an existing cause and effect relationship. Further investigations are necessary for example, a large controlled prospective long-term study, to further refine an association between the corticosteroid dose, the duration of treatment and other risk factors. Dermatologists who prescribe oral corticosteroids, should always be aware of the potential risk of avascular femoral head necrosis and the patients should be informed about this severe complication of oral coricosteroid therapy.