Comparison of Intra-articular Injection of Hyaluronic Acid and N-Acetyl Cysteine in the Treatment of Knee Osteoarthritis: A Pilot Study.

Objective To compare the relative effectiveness of intra-articular N-acetyl cysteine (NAC) and hyaluronic acid (HA) on pain, function and cartilage degradation markers in patients with mild to moderate knee osteoarthritis (OA). Design We prospectively conducted a clinical trial with 20 patients having a diagnosis of Kellgren-Lawrence grade 2-3 knee OA, and randomly allocated to the HA or NAC groups. Groups were matched on age, sex, and body mass index. Injections of 3-mL HA (Hylan G-F 20) or 3-mL NAC (Asist ampoule) were administered as a single shot. Functional status and pain were evaluated before and after injection, using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and the visual analogue scale (VAS) scores. Pre- and posttreatment concentrations of serum C-reactive protein (CRP), synovial fluid chondroitin-6-sulfate (C-6S), matrix metalloproteinase-3 (MMP-3), cross-linked C-terminal telopeptide of type 2 collagen (CTX-II), total oxidant status (TOS), and total antioxidant concentration (TAC) were obtained. Results WOMAC, VAS scores, and CRP levels were comparable between groups prior to treatment. Both HA and NAC produced comparable reductions in TOS and MMP-3. NAC was more effective in reducing C-6S and CTX-II ( P < 0.05). No effects on TAC were noted. Conclusions NAC is effective in lowering some cartilage degradation markers, with comparable outcomes to HA for pain and function. NAC could provide a cheaper alternative to HA for intra-articular injection treatment of mild to moderate knee OA. Future placebo controlled trials are warranted to evaluate effectiveness in a larger patient population with a wider range of age and OA severity.

Neopterin, Interleukin-6, Procalcitonin, C-Reactive Protein And PET-CT Staining As Markers In Infected Total Knee Prosthesis, A Retrospective Analysis.

Diagnosis in prosthetic joint infections is challenging as symptoms are variable, and currently most of the diagnostic tests are non-specific. Normal inflammatory reactions after orthopedic prosthetic surgery may generate false positives, as these tests have high sensitivity but low specificity. Thus, specific tests, as alpha defensin, are needed to distinguish bacterial infections from reactions to surgical trauma. The aim of this study was to determine the sensitivity and specificity of several diagnostic tools for detecting bacterial infection in prostheses. Between April 2010 and December 2012, we analyzed white blood cell count, erythrocyte sedimentation rate, C-reactive protein, neopterin, interleukin-6, and procalcitonin in 45 patients with prosthetic infection confirmed by positive cultures of joint aspirate and deep tissue biopsy. In addition, these patients underwent PET-CT imaging, in accordance with infection protocols in place at our clinic. The suitability and diagnostic power of these tests were assessed by using Shapiro-Wilk test, Mann-Whitney U test, and ROC curve analysis, and by comparing to 40 age- and gender-matched volunteers who underwent unilateral total knee prosthesis with normal serum indices and without known diseases. Significant differences were observed between infected patients and control volunteers (p < 0.05) for all parameters examined. Highest sensitivity (99%) and specificity (98%) were achieved using a combination of interleukin-6 and C-reactive protein. However, PET-CT imaging had diagnostic accuracy of 93.3%. A combination of interleukin-6 and C-reactive protein also enables accurate diagnosis. PET-CT may be an important imaging modality for detecting prosthesis infection. But, these markers were found neither sensitive nor specific in the diagnosis of periprosthetic infection as alpha defensin.

The inflatable intramedullary nail for humeral shaft fractures.

BACKGROUND: We assessed the results of humeral shaft fracture fixation using the inflatable intramedullary nail using radiological and clinical findings. METHODS: From 2012 to 2015, we treated 14 patients with humeral shaft fractures using inflatable intramedullary nail after closed reduction. RESULTS: The mean follow-up time was 14.1 months. The mean time to bone union was 4.5 months. None of the patients had major perioperative mechanical complications or postoperative complications, except for the occurrence of fixation loss and non-union in one patient. CONCLUSION: Inflatable intramedullary nails seem to be applicable, safe and effective for humeral AO/OTA type A midshaft fractures.

Surgical versus conservative treatment following acute rupture of the Achilles tendon: is there a pedobarographic difference?

INTRODUCTION: Controversy remains regarding the optimal treatment method and postoperative rehabilitation of acute Achilles tendon ruptures. In this study, pedobarographic assessments of surgical and conservative treatments were compared. MATERIAL AND METHODS: A prospective assessment was made of 16 patients (eight surgical, eight conservative) and eight healthy controls using a plantar pressure measurement system. Biomechanical gait parameters were obtained using the Footscan dynamic gait analysis system. Kruskal-Wallis and Mann-Whitney U-tests were used for the evaluation of data. RESULTS: Nineteen males and five females were assessed, with an average age of 42.0±11.9 years. Follow-up was completed in 16 patients. No statistically significant difference was determined between the two treatment groups with regard to the gait analysis, but a difference was observed with the control group (P<0.001). All patients were able to resume their prior activities after 6 months and regained normal ranges of motion, with a high rate of satisfaction. Most of the patients (75%) were able to return to their pre-injury level of activities. CONCLUSION: Satisfactory results were obtained through conservative treatment of acute ruptures of the Achilles tendon. No significant differences or complications were observed in the group managed conservatively versus the group treated surgically. Further studies including 3D gait analyses and tendon biomechanical research are required to further investigate this issue.

Symptomatic flexible flatfoot in adults: subtalar arthroereisis.

Flexible flatfoot is a common deformity in pediatric and adult populations. In this study, we aimed to evaluate the functional and radiographic results of subtalar arthroereisis in adult patients with symptomatic flexible flatfoot. We included 26 feet in 16 patients who underwent subtalar arthroereisis for symptomatic flexible flatfoot. Radiographic examination included calcaneal inclination angle, lateral talocalcaneal angle, Meary's angle, anteroposterior talonavicular angle, and Kite's angle. The clinical assessment was based on the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot scale and a visual analog scale (VAS). The mean follow-up was 15.1±4.7 months. The mean preoperative AOFAS score was 53±6.6, while the mean AOFAS score at the last follow-up visit was 75±11.2 (P<0.05). The mean visual analog scale score was 6.9±0.6 preoperatively and 4.1±1.4 at the last follow-up visit (P<0.05). The mean preoperative and postoperative values measured were 13.4°±3.3° and 14.6°±2.7° for calcaneal inclination angles (P<0.05); 35.7°±6.9° and 33.2°±5.3° for lateral talocalcaneal angles (P>0.05); 8°±5.3° and 3.3±3 for Meary's angles (P<0.05); 5.6°±3.5° and 2.6°±1.5° for anteroposterior talonavicular angles (P<0.05); and 23.7°±6.1° and 17.7°±5° for Kite's angles, respectively (P<0.05). Implants were removed in three feet (11.5%). Subtalar arthroereisis is a minimally invasive procedure that can be used in the surgical treatment of adults with symptomatic flexible flatfoot. This procedure provided radiological and functional recovery in our series of patients.

Prosthetic hip joint infection caused by Rothia dentocariosa.

Rothia dentocariosa is an aerobic, pleomorphic, catalase-positive, non-motile, gram-positive bacteria that is a part of the normal flora in the oral cavity and respiratory tract. Although it is a rare cause of systemic infection, it may be observed in immunosuppressed individuals. Here we report the case of an 85-year old man who developed prosthetic joint infection that was caused by R. dentocariosa after hemiarthroplasty. This is the first case report of a prosthetic hip joint infection caused by R. dentocariosa in the literature.

Is cemented bipolar hemiarthroplasty a safe treatment for femoral neck fracture in elderly patients?

OBJECTIVES: Controversy exists regarding the use of cement in hemiarthroplasty when treating a displaced femoral neck fracture in elderly patients. The primary hypothesis of this study was that the use of cement would afford better visual analog pain and activity scores in elderly patients. METHODS: This study included 133 patients over 65 years of age admitted to our clinics from 2006 to 2012 for the surgical treatment of a displaced femoral neck fracture. All patients were treated via hemiarthroplasty. The patients (66 males, 67 females; mean age: 78.16 years; range: 60-110 years) were followed-up regularly. All patients were divided into one of two groups: group A was treated with cement; and group B without. Both groups were compared in terms of preoperative features (demographics and associated diseases), pre- and postoperative complications, mortality rates, pain and activity levels, and hip scores. Hospitalization time, average surgical duration, and time from fracture to operation were also recorded. Mean follow-up duration was 30.9 (range: 5-51) months. RESULTS: We found no significant between-groups differences in terms of length of hospital stay, Harris Hip Score, complications, or follow-up mortality rates. Walking ability and pain scores were better in the cemented group in the early follow-up period. Duration of surgery and perioperative mortality rates were somewhat lower in the cementless group, but the difference was not statistically significant. CONCLUSION: The use of cement during hip hemiarthroplasty in patients over 65 years of age had no negative impact on mortality or morbidity. Hemodynamic changes during cement application are important, but it is noteworthy that patients fitted with cemented endoprostheses had increased levels of activity and lower pain levels.

[A giant hydatid cyst localized in pelvis and thigh]. / Pelvis ve uyluk yerlesimli dev kist hidatik.

A hydatid cyst is a parasitic disease which is caused by a cestode named Echinococcus and often located in the liver. Localization in the bone and soft tissue is rarely seen. In this article, we present a 64-year-old male case with a hydatid cyst located in the soft tissue of the left anterolateral aspect of the thigh. The hydatid cyst starting from the gluteal region proximally into the pelvis, the femoral head and the hip joint leading to the spread of secondary protrusio acetabuli and extending distally to the popliteal region formed a massive lesion. In addition to medical treatment followed by repeated surgeries, the patient with relapses is still under surgical follow-up and medical treatment.

Effects of intra-articular administration of autologous bone marrow aspirate on healing of full-thickness meniscal tear: an experimental study on sheep.

OBJECTIVE: The aim of this study was to evaluate the effects of bone marrow-derived mesenchymal stem cell and bone marrow elements on the healing of meniscal tears. METHODS: This study was performed on twelve, 2-year-old male Tahirova sheep. In each subject, one knee was used for experiment purposes and the other knee was used as a control. After creating a longitudinal full-thickness tear in the red-white zone of the medial meniscus, aspirated autologous bone marrow material was injected into the tear site in the experiment group. The control group received no intervention for secondary healing. RESULTS: In the macroscopic evaluation of meniscus, a bridging reparation tissue and adhesion were observed between the rims of the tear in the experiment group. There was no statistical difference in collagen fibril formation between the groups (p=0.16). There was significantly more neovascularization in the experiment group than the control group (p=0.003). The cell count was also a significantly higher in the experiment group (p=0.004) and formation of cartilage plaques was more frequent in the experiment group (p=0.016). There was no evidence suggesting intrinsic repair in the meniscus of control group by light and electron microscopy. CONCLUSION: An injection of bone marrow into the meniscus tear site improves healing in a meniscal tear model as demonstrated by both light and electron microscopic findings.

The effect of zymosan and the protective effect of various antioxidants on fracture healing in rats.

AIM: To investigate the effects of free oxygen radicals and various antioxidants on bone healing after experimental formation of fracture. MATERIALS AND METHODS: Fifty male rats were used and divided into five groups (ten rats in each). The right forelimbs of the rats were broken by bimanual compression method. One hour before this procedure, 5 ml/kg of intraperitoneal (i.p.) physiologic saline were given to the control Group 1. All 40 rats in the experimental Groups 2, 3, 4 and 5 were treated with i.p. zymosan at a dosage of 100 mg/kg to induce the production of free radicals by stimulating NADPH oxidase in polymorphonuclear leukocytes. Zymosan induction was stopped on the fifth post-fracture day. In addition to the zymosan, i.p. 1 g/kg/day of dimethyl sulfoxide were given to the animals in Group 3, 50 mg/kg/d of Ginko biloba Extract (EGb 761) in Group 4 and 500 mg/kg/day of vitamin C in Group 5. Radiographs of the fractures of all animals were obtained to assess callus formation, remodeling and bridging bone formation under ether anesthetics on postfracture day 7, 14 and 21. All rats were euthanized on day 22, and sections of the radius and ulna were examined both histologically with light and electron microscopy and ultrastructurally. Statistical analysis was made with Kruskal-Wallis variance analyze test and comparison between groups was performed by Dunn's multiple comparison test. RESULTS: An impairment of bone healing was observed in Group 2 inducted with purely zymosan. Variable results were obtained for bone healing in the groups treated with various antioxidants. There was very significant difference of fracture healing between Groups 1 and 2 both histologically and radiologically (P < 0.001). There was significant difference between Groups 2 and 5 radiologically (P < 0.05). CONCLUSION: Free oxygen radicals demonstrate a negative effect on fracture healing and vitamin C (an antioxidant) partially prevents the negative effect of zymosan on fracture healing.

Primary hydatid cyst of the thigh: a case report of an unusual localization.

The sartorius muscle is a rare location of primary hydatid cyst. In this report, the clinical, pathologic, and radiologic features are discussed, with special emphasis on the pathologic and radiographic features. We report a case of hydatid cyst of the proximal thigh in an eight-year-old girl. Magnetic resonance (MR) images revealed muscular hydatid cyst in the sartorius muscle, with a striking appearance of daughter cysts. We did not find any visceral organ involvement. Wide excision was performed without destroying the cyst wall. Primary muscular hydatidosis should be kept in mind in the differential diagnosis of a cystic mass of a skeletal muscle.

Influence of maternal nicotine exposure on neonatal rat bone: protective effect of ascorbic acid.

Limited research in young adults and immature animals suggests a detrimental effect of tobacco on bone during growth. We aimed to determine the adverse effects of maternal nicotine exposure during pregnancy and lactation on neonatal rat bone development, and to determine a protective effect of ascorbic acid. Gravid rats were assigned into three groups: two experimental and one control (group I). In the first experimental group (group II), pregnant rats received 3 mg/kg/d nicotine subcutaneously during pregnancy from 1 to 21 days of gestation and lactation (until postnatal day 21). The second experimental group (group III) received nicotine and ascorbic acid (1 mg/kg body mass/d). Whole body mineral density (BMD), content (BMC), and area (BA) were measured on postnatal day 21. Histopathologic and morphologic findings of the femur were obtained. Maternal nicotine exposure decreased the body weight of the rat at the birth and postnatal day 21. The values of BMD, BA, and BMC of the groups were similar to each other. Width of the epiphyseal plate and the hypertrophic zone were higher in group III but lower in group II than in group I. Number of apoptotic chondrocytes was significantly increased in group II. The length of femur was higher in group I but lower in group II than in group III. Maternal nicotine exposure during gestation and lactation resulted in decreased body weight and bone lengthening. Ascorbic acid supplementation was found to prevent the adverse effects of maternal nicotine exposure on the growth plate.

The effect of subcutaneously injected nicotine on achilles tendon healing in rabbits.

The objective of this study was to evaluate the effect of subcutaneously injected nicotine on transversely transected and sutured achilles tendon healing in an experimental rabbit model. Adult New Zealand rabbits (n=22) weighting 3,000-3,500 g were used in this experimental study. Rabbits were randomly divided into two groups. Achilles tendon was transversely incised and repaired in all animals. In the experiment group subcutaneous injection of Nicotine tartrate 3 mg/kg/day was done. In the control group Serum physiologic injection was done at the same dosage. The injections were made three times a day in equal dosages. Nicotine and SF injections were made until the end of the 8-week, and then all animals were euthanized. Both light microscopic and electron microscopic evaluations were made on 14 animals. In N group light microscopic evaluation showed a visible gap in repair site. The total tendon score represented in N group was less than in SF group. The statistical analysis of the groups was significantly different for total tendon scores (P=0.002). Beside this electron microscopic examination showed inactive and degenerated fibroblasts and irregular collagen fibrils around them as well as collagen synthesis interruption in N group. Biomechanical evaluation was made on eight animals. The average tensile strength values in Group N (139.47+/-44.55 N) were significantly lower than those in Group SF (265.9+/-39.01 N) (z=2.309, P=0.029). Nicotine is the major chemical component common to all cigarettes and previously has been shown to affect wound and fracture healing adversely. The results of this study show that nicotine impairs achilles tendon healing after a surgical repair.

Is intraarticular sodium hyaluronate injection an alternative treatment in patients with adhesive capsulitis?

The aim of this study was to compare the efficacy of sodium hyaluronate (SH) injection with the most common treatment methods, intraarticular steroid injection and physical therapy modalities in patients with adhesive capsulitis (AC). A total of 95 shoulders of 90 patients were included in the study and were randomized in four groups. The patients were treated with SH injection (group 1), triamsinolone acetonide (group 2) or physical therapy modalities (group 3). Group 4 patients were served as controls. Pain severity, passive ranges of motion and functional considerations were measured before, and 15 days and 3 months after the treatments. In all treatment groups, there were significant improvements at both the 15th day and third month in all parameters (for each, p<0.001). The passive abduction values on the 15th day was found significantly higher in group 3 when compared with group 1 and controls (for each, p<0.001). At the third month, the passive abduction values of the groups 2 and 3 were improved when compared with the control group (p<0.001). Constant score was higher in group 3 on 15th day when compared with group 1. At the third month, all treatment groups were improved significantly compared with control group (p<0.001). We provided the best results in physical therapy modalities applied group for AC treatment. However, we think that SH injection may be administered as an alternative treatment method.

Serum levels of soluble P-selectin are increased and associated with disease activity in patients with Behçet's syndrome.

Behçet's syndrome (BS) is a relapsing, chronic, inflammatory disease characterized by endothelial dysfunction, atherothromboembogenesis, and leukocytoclastic vasculitis with complex immunologic molecular interactions. Generalized derangements of the lymphocyte and neutrophil populations, activated monocytes, and increased PMNLs motility with upregulated cell surface molecules such as ICAM-1, VCAM-1, and E-selectin, which are found on the endothelial cells, leukocytes, and platelets, have all been demonstrated during the course of BS. Our aim is to investigate the association of serum concentrations of soluble P-selectin in patients with BS, and to evaluate whether disease activity has an effect on their blood levels. This multicenter study included 31 patients with BS (15 men and 16 women) and 20 age- and sex-matched healthy control volunteers (11 men and nine women). Neutrophil count, erythrocyte sedimentation rate, and acute-phase reactants as well as soluble P-selectin levels were determined. The mean age and sex distributions were similar (P > .05) between BS patients (35 years) and control volunteers (36 years). Serum levels of soluble P-selectin in patients with BS (399 +/- 72 ng/mL) were significantly (P < .001) higher when compared with control subjects (164 +/- 40 ng/mL). In addition, active BS patients (453 +/- 37 ng/mL) had significantly (P < .001) elevated levels of soluble P-selectin than those in inactive period (341 +/- 52 ng/mL). This study clearly demonstrated that serum soluble P-selectin levels are increased in BS patients when compared with control subjects, suggesting a modulator role for soluble P-selectin during the course of platelet activation and therefore, atherothrombogenesis formation in BS, especially in active disease.

Synovial nitric oxide concentrations are increased and correlated with serum levels in patients with active Behçet's disease: a pilot study.

Behçet's disease (BD) is a relapsing immunoinflammatory vasculitis of unknown etiology characterized by endothelial dysfunction. Articular symptoms and signs are present in about 75% of cases and characterized by seronegative arthritis and nonspecific synovitis. We demonstrated that both serum and erythrocyte nitric oxide (NO(.)) levels, the most abundant free radical in the body, were elevated in BD and associated with disease activity. This study further investigated NO(.) levels in the synovial fluid and serum from patients with active and inactive BD. A total of 23 BD patients with articular involvement (14 men and 9 women) satisfying International Study Group criteria and 15 age- and sex-matched healthy control subjects (9 men and 6 women) undergoing elective arthroscopy were included in this case-control investigation. The synovial fluid and serum were obtained from BD patients and controls. Clinical and laboratory findings including neutrophil count and erythrocyte sedimentation rate (ESR) were used to classify BD patients as active (n = 11) or inactive (n = 12). Synovial as well as serum NO(.) levels were compared between the groups and correlation analysis was performed. Acute phase reactant levels were significantly higher (for each, p < 0.01) in BD patients than control subjects in the active period. The mean synovial NO(.) level in active Behçet's patients (mean +/- SD 76.61 +/- 11.95 micromol/l) was significantly higher than in inactive patients (46.16 +/- 8.89 micromol/l, p < 0.001) and healthy control subjects (39.60 +/-8.03 micromol/l, p < 0.001). The difference between inactive patients and controls was not significant (p > 0.05). Active BD patients had significantly higher serum NO(.) levels (38.84 +/- 9.15 micromol/l) than inactive patients (30.91 +/- 5.88 micromol/l, p = 0.018) and control subjects (28.86 +/- 5.91 micromol/l, p = 0.002). In addition, synovial NO(.) levels were positively correlated with serum levels (r(2) = 0.621, p < 0.001). Increased synovial NO(.) levels in active BD patients probably reflect a nonspecific inflammatory process of the synovium and, therefore, arthralgia and arthritis as a common finding of BD.

[Arthroscopic evaluation of the mobility of the meso-acromion]. / Mezo-akromiyon hareketinin artroskopik olarak degerlendirilmesi.

OBJECTIVES: Failure of fusion of the secondary centers of ossification of the acromial apophyses is a pathology that should be included in the differential diagnosis of shoulder pain and subacromial impingement syndrome. Mobility of the meso-acromion is of particular importance in choosing the appropriate treatment. This study presents a new arthroscopic method to evaluate the mobility of os acromiale. METHODS: We presented the arthroscopic evaluation and surgical treatment of three women (mean age 43.3 years; range 34 to 53 years) with shoulder pain and a radiographically confirmed meso-acromiale. The Neer and Hawkins impingement signs were positive and palpation over the acromion gave rise to pain. Axillary radiographs showed a meso-acromion in all the affected shoulders. Magnetic resonance imaging showed a rotator cuff tear in one patient. During arthroscopic examination the motility of the meso-acromion was dynamically observed in the subacromial region and the rotator cuff tear was repaired. Acromioplasty was not performed. Following removal of pseudarthrotic areas, the mobile meso-acromion was fixed with a cerclage wire, two cannulated screws and bone grafting, followed by a tension-band configuration. The mean follow-up was five years (range 3 to 6 years). RESULTS: Union occurred in all the patients. None of the patients had shoulder pain at rest or during activities. When compared with the normal side, the range of motion and the strength of the shoulder were normal in all the patients, with Constant scores being 89, 96, and 98, respectively. CONCLUSION: Identification of the type of os acromiale is important for the treatment plan. The meso-acromion is particularly important because of its greater size and its role in narrowing the subacromial space. It is necessary to determine whether the meso-acromion fragment is mobile. Dynamic arthroscopic examination offers significant help in this respect.

Tumour necrosis factor alpha, lipid peroxidation and NO* are increased and associated with decreased free-radical scavenging enzymes in patients with Weill-Marchesani syndrome.

AIM: Weill-Marchesani syndrome (WMS) is a rare systemic disorder with both autosomal recessive and dominant inheritances. Accumulation of reactive oxygen species such as O2*-, H2O2 and OH* causes lipid peroxidation (LPO), whereas antioxidant enzymes (superoxide dismutase (SOD), glutathione peroxidase (GSHPx)) mediate defence against oxidative stress. Excess tumour necrosis factor (TNF)-alpha and NO* react with O2*- and cause further antioxidant depletion with an increase in mutation frequency by H2O2. This study investigated the levels of SOD, GSHPx, catalase (CAT), TNF-alpha, NO and LPO in patients with WMS. METHODS: A group of 10 WMS patients (four males, six females; age, 26.5+/-19.0 years) and 10 age-matched and sex-matched controls (five males, five females; age, 27.3+/-18.2 years) were included. Serum TNF-alpha levels were determined by a spectrophotometer technique using immulite chemiluminescent immunometric assay. Malondialdehyde (MDA) was determined in plasma; CAT in red blood cells (RBCs), and SOD and GSHPx in both plasma and RBCs. Total serum NO* levels were evaluated by Griess reaction. RESULTS: Mean levels of TNF-alpha (8.3+/-0.6 pg/ml) in WMS patients were significantly (p<0.001) higher than controls (4.3+/-0.2 pg/ml). Plasma MDA levels in patients and controls were 5.4+/-0.8 and 1.8+/-0.6 micromol/l, respectively, and the difference was significant (p=0.0002). SOD and GSHPx activities were significantly lower in both RBCs and plasma of WMS than in controls (RBC-SOD, 3981.9+/-626.6 versus 5261.6+/-523.0 U/g haemoglobin (Hb), p=0.0005; plasma-SOD, 529.4+/-49.3 versus 713.4+/-55.7 U/g protein, p=0.0002; RBC-GSHPx, 682.7+/-42.0 versus 756.5+/-47.6 U/g Hb, p=0.0011; plasma-GSHPx, 107.3+/-15.0 versus 131.4+/-19.7 U/g protein, p=0.0113). In addition, serum NO (NO*-2 + NO*-3) levels were also significantly (p = 0.0002) increased in WMS patients (54.4+/-5.7 versus 26.9+/-6.7 micromol/l). RBC-CAT levels were similar between groups (125.6+/-21.3 versus 131.0+/-21.5 k/g Hb, p = 0.8798). CONCLUSIONS: The elevated LPO, TNF-alpha and NO* with decreased antioxidant enzyme activities indicated impaired antioxidative defence mechanisms with an oxidative injury and cell toxicity in WMS patients. The use of multiple antioxidants and free radical scavengers might be helpful in this genetic disorder.