Hyperhomocysteinemia is associated with deep venous thrombosis of the lower extremities in Tunisian patients.

OBJECTIVES: To test the association between hyperhomocysteinemia (HHC) and deep venous thrombosis (DVT) of lower extremities in Tunisians. DESIGN AND METHODS: This case-control study included 90 patients with DVT of the lower extremities and 160 healthy controls. Plasma homocysteine, vitamin B(12) and folate were determined using immunoenzymatic methods. Logistic regression models were performed to test whether the association between HHC and DVT is independent and to precise determinants of HHC in DVT patients. RESULTS: Plasma total homocysteine concentrations were significantly higher in patients with DVT (17.4+/-11.5 micromol/L) and in patients with idiopathic DVT (15.2+/-6.4 micromol/L) as compared to controls (11.5+/-3.3 micromol/L). HHC was significantly associated (p<0.001) with all DVT (OR, 8.82; 95% CI, 3.96-19.6) as well as idiopathic DVT (OR, 7.40; 95% CI, 3.01-10.8). These associations persisted after adjustment for several thrombosis risk factors. In patients with DVT, HHC was related to folate and vitamin B(12) concentrations, but neither to the type of occurrence nor to the recurrence of DVT. CONCLUSION: HHC is independently associated with first DVT of lower extremities in Tunisians. Homocysteine should be assessed in patients with DVT and the effect of vitamin B supplementation should be tested among them.

[Oxidative stress in end stage renal disease: evidence and association with cardiovascular events in Tunisian patients]. / Stress oxydant chez les insuffisants rénaux chroniques: evidence et association avec les maladies cardiovasculaires chez des urémiques Tunisiens.

We assessed oxidative stress in 35 chronic renal failure under conservative treatment (CRF), 50 hemodialysed (HD) and 30 renal transplant (RT) patients, and 31 age- and sex-matched healthy subjects. Compared to controls, CRF patients exhibited significantly higher conjugated dienes (139 +/- 37 versus 121 +/- 22 micromol/l) and LDL oxidation (126 +/- 65 versus 99 +/- 46 micromol/l). Glutathione peroxidase activity was decreased in CRF and HD (5.31 +/- 2.46 and 5.39 +/- 2.32 versus 7.42 +/- 2.72 U/ml in healthy subjects). Superoxide dismutase activity was lower in HD (91 +/- 38 U/ml) and higher in RT patients (132 +/- 33 U/ml) than controls (116 +/- 30 U/ml). Plasma zinc concentrations were significantly decreased in CRF and HD patients and copper concentrations were significantly decreased in TPR. Plasma selenium levels were normal in the three groups of patients. Vitamin A was significantly increased, whereas vitamin E was normal in the 3 groups of patients compared to healthy controls. Total antioxidant status was increased in CRF and HD, but not in RT patients. Patients with cardiovascular disease showed increased serum copper, and significantly decreased glutathione peroxidase activity. This study revealed an oxidative stress in CRF and HD patients that may favour the development of cardiovascular diseases.

Hyperhomocysteinaemia is associated with uveitis but not with deep venous thrombosis in Behcet's disease.

Plasma homocysteine was assessed in Behcet's disease (BD) patients in order to determine the prevalence of hyperhomocysteinaemia in BD and to test its association with clinical manifestations of the disease. The study included 59 patients with BD and 118 age- and sex-matched healthy subjects. Plasma homocysteine, vitamin B(12) and folate were assessed by automated immunoassay methods. Hyperhomo-cysteinaemia was defined as plasma homocysteine >15 micromol/l. Plasma homocysteine concentrations and the prevalence of hyperhomocysteinaemia were significantly higher in BD patients than in controls [median (5th-95th percentile), 11.3 (6.6-28.1) vs. 10.6 (6.6-17.1) micromol/l, and 25.4% vs. 9.3%, respectively]. In BD patients, hyperhomocysteinaemia was related to male gender, disease severity and uveitis [odds ratio (OR), 5.32; 95% confidence interval (CI), 1.43-21.61; p = 0.008], but not to age, smoking, disease activity, deep venous thrombosis, arthritis or neurological involvement. The association between uveitis and hyperhomocysteinaemia persisted (multi-adjusted OR, 7.46; 95% CI, 1.03-54.3; p = 0.05) after adjusting for gender, age, disease activity and duration, smoking, deep venous thrombosis, and serum concentrations of creatinine, vitamin B(12) and folate. Plasma homocysteine should be measured in patients with BD, and the effect of B-vitamin supplementation should be tested in those with hyperhomo-cysteinaemia.

Benzene exposure monitoring of Tunisian workers.

To monitor benzene exposure and to check reliability of urinary trans,trans-Muconic Acid (t,t-MA) as a bio-marker of benzene exposure in local conditions, a study was conducted on 30 Tunisian exposed workers (20 tanker fillers and 10 filling station attendants). The analyses were carried out on environmental air and urinary t,t-MA before (t,t-MAA) and at the end of work shift (t,t-MAB). 20 nonoccupationally exposed subjects were also investigated. The average value of environmental benzene concentration was 0.17 ppm. The differences between t,t-MAA and t,t-MAB concentrations and between t,t-MAB and t,t-MA measured in controls (t,t-MAC) were both significant (p < 0.001). Benzene air concentrations were well correlated with t,t-MAB: R = 0.76. In the nonexposed group, average t,t-MA concentrations is significantly higher among smokers than nonsmokers (P < 0.02). Analysis of urinary t,t-MA offers a relatively simple and suitable method for benzene exposure monitoring.