The genetic association between PON1 polymorphisms and osteonecrosis of femoral head: A case-control study

The purpose of this study was to investigate the relationship between Paraoxonase-1 (PON1) gene rs662, rs854555 polymorphisms and osteonecrosis of the femoral head (ONFH) in Han population, northern China.Polymerase chain reaction-restriction fragment length polymorphism was used to determine genotypes of PON1 polymorphisms in 84 patients with ONFH and 96 healthy persons. χ test was used to compare distribution differences of genotype, allele, and haplotype between the case and control groups. The odds ratio (OR) and 95% confidence interval (CI) were calculated to reveal the effects of PON1 polymorphisms on risk of ONFH, and the results were adjusted using logistic regression analysis. The linkage disequilibrium and haplotype analysis were performed with haploview software.That people carrying AA genotype of rs662 were easier to be attacked by ONFH than GG genotype carriers (OR = 2.53, 95% CI = 1.05-6.07, P = .038). Meanwhile, the frequency of A allele in the case group was significantly higher than the controls and it was a risk factor for ONFH (OR = 1.56, 95% CI = 1.03-2.38, P = .038). The A-A haplotype frequency of rs854555-rs662 in PON1 was significantly correlated to the increased susceptibility to ONFH (OR = 2.74, 95% CI = 1.28-5.84).The rs662 polymorphism in PON1 may be associated with ONFH susceptibility, but not rs854555 in Han population, northern China. Additionally, haplotype is also a nonignorable risk factor.

Genetic association of the ApoB and ApoA1 gene polymorphisms with the risk for alcohol-induced osteonecrosis of femoral head

Polymorphisms of apolipoprotein B (ApoB), apolipoprotein A1 (ApoA1) gene and ApoB/ApoA1 Ratio were associated with lipid metabolism disorders in previous reports. The aim of this study assess whether variation of ApoB, ApoA1 gene are associated or not with alcohol-induced osteonecrosis of femoral head (ONFH). In a case-control study, we genotyped 4 single-nucleotide polymorphisms (SNPs) in ApoB and ApoA1 genes in 209 alcohol-induced ONFH patients and 300 healthy control subjects in Han Chinese population using χ(2) test and genetic model analysis. The analysis revealed that the frequencies of ApoB and ApoA1 genotypes were significantly different in alcohol-induced ONFH patients than in controls. We identified rs1042034, rs676210 and rs673548 in ApoB gene were associated with decreased risk of alcohol-induced ONFH using recessive model analysis (odds ratio [OR], 0.44; 95% confidence interval [CI], 0.19-0.99; P = 0.042), the OR, CI, P value of three SNPs were the same after adjusted for gender + age. We also identified rs632153 in ApoA1 gene was associated with increased risk of alcohol-induced ONFH using allele model (OR, 1.83; 95% CI, 1.16-2.88; P = 0.008) and log-additive model (adjusted OR, 1.77; 95% CI, 1.00-3.14; P = 0.046), analysis respectively. Haplotype analysis demonstrated no difference between ApoB and alcohol-induced ONFH. Polymorphisms of the ApoB and ApoA1 gene are associated with alcohol-induced ONFH in the Han Chinese population.

Association of apolipoprotein A5 genetic polymorphisms with steroid-induced osteonecrosis of femoral head in a Chinese Han population

BACKGROUND

Previous studies suggested that apolipoprotein A5 (ApoA5) genetic polymorphisms (SNPs) may result in lipid metabolism disorders. Therefore, genetic polymorphisms in ApoA5 may be associated with the occurrence of osteonecrosis of femoral head (ONFH).

METHODS

We designed a case-control study including 223 patients of osteonecrosis and 201 age- and sex-matched control subjects to analyze the association between ApoA5 polymorphisms and susceptibility of steroid-induced ONFH. We utilized polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to genotype two SNPs (rs662799 and rs3135506) in ApoA5 gene.

RESULTS

We found both rs662799 and rs3135506 were associated with the risk of ONFH in codominant, dominant, and recessive model, respectively. Haplotype analyses suggested that T-C haplotype was associated with decreased risk of ONFH, whereas the haplotype C-C was significantly associated with an increased risk of ONFH.

CONCLUSION

Our study suggested that ApoA5 genetic polymorphisms were associated with susceptibility to ONFH in Chinese population. However, our results need further investigation with large sample size and various populations.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_229.

Prevalence and risk factor for symptomatic avascular necrosis development in Thai systemic lupus erythematosus patients

BACKGROUND

Avascular necrosis (AVN) has been reported in systemic lupus erythematosus (SLE) and most SLE patients suffer from this problem.

OBJECTIVES

To study the prevalence of AVN in Thai SLE patients and to determine the risk factors for developing AVN.

METHODS

A retrospective study was performed, between January 1, 1995 and August 31, 2005, on patients over 15 years of age in Khon Kaen, Thailand.

RESULTS

The medical records of 736 SLE patients were reviewed. The female to male ratio was 15.4:1. The prevalence of AVN was 8.8%. The average age at the time of AVN detection was 27 years (range, 18-54) and the average duration of disease 69 months (range, 12-112). All cases were AVN of the hip joint. The factors correlated with AVN included: long duration of disease, history of previous septic arthritis in the ipsilateral hip to the AVN development, hematological involvement, gastrointestinal involvement, arthritis and cutaneous vasculitis. After regression analysis, hematological involvement and long duration of disease were associated with AVN with a respective odds ratio of 3.13 (95% CI 1.13-8.54) and 1.01 (95% CI 1.00-1.02). Neither high-dose steroid nor antimalarial treatment were correlated with AVN in our study and 4.6% (n = 3) of patients had never received steroid therapy during the follow-up period.

CONCLUSION

Prevalence of symptomatic AVN was 8.8% in our SLE patients. A longer duration of disease and hematological involvement were associated with AVN development.

Lack of association of MTHFR gene polymorphisms with the risk of osteonecrosis of the femoral head in a Korean population

Some studies have suggested that coagulation disorders may be implicated in osteonecrosis of the femoral head (ONFH). The C677T polymorphism of the 5, 10-methylenetetrahydrofolate reductase (MTHFR) gene has been postulated to be a genetic risk factor for venous thromboembolism and osteonecrosis in Caucasians, but this relationship has not been established in other populations. In this study, we conducted case-control analysis of whether MTHFR polymorphisms are associated with ONFH in Korean patients. Fifteen single nucleotide polymorphisms (SNPs) were selected and genotyped in 443 ONFH patients and 273 control subjects using the TaqMan 5' allelic discrimination assay. Comparison of ONFH and control subjects using logistic regression models revealed no statistically significant differences in the frequencies of the MTHFR polymorphisms and haplotypes. Further analysis stratified by etiology also showed no association. These results suggest that MTHFR polymorphisms play no significant role in susceptibility to ONFH in the Korean population.

Genetic background of nontraumatic osteonecrosis of the femoral head in the Korean population

Major thrombophilic mutations have been identified as risk factors for nontraumatic osteonecrosis of the femoral head (ONFH) in Caucasians. We asked whether the genetic background of patients with ONFH in the Korean population was similar. We analyzed factor V G1691A mutation (factor V Leiden), prothrombin G20210A mutation, and methylenetetrahydrofolate reductase C677T and A1298C polymorphisms in 71 patients (53 men, 18 women) with ONFH. We classified these patients as 51 alcohol-induced, 18 idiopathic, one steroid-induced, and one dysbaric. We recruited 200 normal control subjects (128 men, 72 women). We used multiplex PCR/restriction fragment length polymorphism for each genotyping. We observed neither factor V Leiden nor prothrombin G20210A mutation. Although methylenetetrahydrofolate reductase A1298C genotypes were not associated with osteonecrosis, methylenetetrahydrofolate reductase C677T variant genotypes increased the risk of ONFH compared with 677CC. Odds ratios of 677CT and 677CT+TT were 2.00 (95% confidence interval, 1.05-3.81) and 1.96 (95% confidence interval, 1.07-3.59), respectively, compared with 677CC. Our data suggest methylenetetrahydrofolate reductase C677T polymorphism plays a role in the pathogenesis of osteonecrosis in the Korean population. It also implies the genetic risk profile of ONFH may differ among ethnic populations.

Clinically occult avascular necrosis of the hip in systemic lupus erythematosus

OBJECTIVE

To study the natural history of clinically occult avascular necrosis (AVN) of the hip in patients with systemic lupus erythematosus (SLE).

METHODS

Sixty-six patients with SLE (without symptoms referable to the hip) receiving at least 5 mg/day prednisone for > or = 6 months were screened by magnetic resonance imaging (MRI) for AVN of the hip. A complete MRI evaluating class and percentage of femoral head involvement, AP and lateral radiographs of the hips, bone scan, and physical examination were performed for patients with positive MRI. Medical records were reviewed for serologic and clinical variables that might predict AVN. Repeat MRI were obtained at 3, 6, and 12 months to assess possible progression or resolution of the lesion. Patients with negative screening MRI underwent repeat screening after one year to assess the one year incidence rate.

RESULTS

Eleven asymptomatic hips (8%) in 8 patients (12%) had MRI documented AVN. The percentage of femoral head involvement ranged from 1 to 46%. One lesion was MRI class B, the remaining lesions were class A. The radiographic stage of 10 hips was stage 1, the MRI class B hip was stage 2. Risk factors for clinically occult AVN included Afro-American origin, Raynaud's phenomenon, migraine headaches, and a maximal corticosteroid dose of at least 30 mg/day. After 12 months, 43 of 58 patients with an initially negative MRI underwent repeat screening examinations; no new lesions were observed.

CONCLUSION

Clinically occult AVN of the hip is common in patients with SLE. The short term natural history of these lesions appears stable without spontaneous healing or clinical or radiographic progression. Risk factors for these asymptomatic lesions are similar to the risks for symptomatic AVN and surgical intervention appears not to be indicated in these patients.