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Primary hyperoxalurias (PH) are inborn errors in the metabolism of glyoxalate and oxalate with recessive autosomal transmission. As a result, an increased endogenous production of oxalate leads to exessive urinary oxalate excretion. PH type 1, the most common form, is due to a deficiency of the peroxisomal enzyme alanine: Glyoxylate aminotransferase (AGT) in the liver. PH type 2 is due to the deficiency of the glyoxylate reductase/hydroxypyruvate réductase, present in the cytosol of hepatocytes and leucocytes. PH type 3 is linked to the gene HOGA1, encoding a mitochondrial enzyme, the 4-hydroxy-2-oxo-glutarate aldolase. Recurrent urolithiaisis and nephrocalcinosis are the markers of the disease. As a result, a progressive dysfunction of the kidneys is commonly observed. At the stage of severe chronic kidney disease, plasma oxalate increase leads to a systemic oxalosis. Diagnostic is often delayed and it based on stone analysis, cristalluria, oxaluria determination and DNA analysis. Early initiation of conservative treatment including high fluid intake and long-term co-administration of inhibitors of calcium oxalate crystallization and pyridoxine, could efficiently prevent end stage renal disease. In end stage renal failure, a combined liver-kidney transplantation corrects the enzyme defect.

Currently, for the diagnosis of osteoporosis, we search risk factors and measure bone mineral density (BMD) by DXA method. However, bone turnover markers, unused still in practice, have shown an interest especially in the prediction of fracture risk. aim: To determine the relationship between bone markers, BMD and osteoporotic fracture. methods: Prospective study of 65 women referred for measure of BMD during the period between May and August 2010. Each patient had a dosage of serum bone formation markers: osteocalcin (OC) and N-terminal propeptide of type I collagen (P1NP) and bone resorption markers: serum and urinary C-terminal telopeptide of type I collagen (β-CTX or CrossLaps) as well as parathyroid hormone and calcium. Risk factors of osteoporosis were identified in each case. results: Our 65 women had a mean age of 58.6 ± 12.1 years. The majority (83%) were menopausal women. Osteoporosis was found in 52%, osteopenia 26% and normal BMD 22% of cases. An increase in bone turnover markers was correlated with menopause (p = 0. 001 for the OC, p = 0.016 for urinary CTX), a low body mass index (p = 0.015 for OC, p = 0.042 for serum CTX) and osteoporosis (p0.001 for P1NP, p0.001 for serum and urinary CTX). Corticosteroid therapy was correlated with a decrease in bone formation markers (p = 0.002 for P1NP). The presence of fracture was only associated with increased urinary CTX (p = 0.05).Bone turnover markers increase in menopausal women and in case of low BMD. However, their contribution in the diagnosis of osteoporosis is low. They are rather an interest in the prediction of fracture risk.

L’objectif de ce travail est d’etudier les details de la phase pre-analytique (PPA) en microbiologie afin de determiner les ecarts avec les exigences du Guide de bonnes pratiques de laboratoire (GBPL), les causes de dysfonctionnement et les actions a entreprendre pour ameliorer la qualite de la PPA dans notre etablissement. Materiels et methodes : L’etude a ete realisee dans le laboratoire de microbiologie de l’hopital de Monastir. Une grille d’auto-evaluation et une enquete de satisfaction aupres du personnel preleveur du laboratoire ont ete etablies. Une revue documentaire a ete realisee conformement aux exigences des textes normatifs (Norme ISO 15189) et reglementaires (GBPL). Les analyses des non-conformites et des risques ont ete effectuees respectivement par la methode des 5M et la methode d’analyse preliminaire des risques (APR). Resultats : Les resultats montrent que le dysfonctionnement reside essentiellement au niveau de la gestion des ressources humaines. L’analyse des causes et l’APR mettent le point sur un manque de sensibilisation et de formation du personnel responsable, une insuffisance dans la communication cliniciens-laboratoire et dans la formulation des methodes (procedures, instructions…). Conclusion : L’etude de la PPA en detail montre que toutes les etapes sont critiques. En effet, la maitrise de cette phase passe par l’application des exigences du GBPL et par la prise de conscience d’une gestion totale de la qualite.

We purpose to verify if paraoxonase 1 (PON1) activity may be a marker of cardiovascular risk in a young Tunisian population with type 1 diabetes (T1D).PON1 activity was measured by a kinetic method using paraoxon as substrate. The other parameters were determined by automated methods.One hundred and nine children and adolescents with T1D and 97 healthy subjects were involved in this study. PON1 activity and PON1/HDL-cholesterol ratio were significantly decreased in diabetics (303 ± 174 vs. 372 ± 180 U/L and 221 ± 139 vs. 298 ± 20 1U/mmol, P=0.006, P=0.002, respectively) compared to controls. A significant increase in total cholesterol, LDL-c and microalbuminuria was observed in diabetics compared to controls. PON1 activity was decreased by 9.5% in patients with diabetes duration ≥ 6 years, by 28.4% for those with fasting glycemia ≥ 7 mmol/L (P0.001), by 14% in those with HbA1c ≥ 8% and by 12.3% for diabetics with dyslipidemia. PON1 activity is reduced when the number of cardiovascular risk factors increases (P0.001).PON1 seems to be associated to cardiovascular risk markers in T1D. This result remains to be seen. Nevertheless, improving PON1 activity could be a significant target for reducing cardiovascular risk.

Capillary electrophoresis of serum proteins is a fast, reliable and simple technique, but many interference exist. The objective of our work is to study the interference of bilirubin on this technique; 70 icteric sera were analysed on Capillarys ™ (Sebia). A second electrophoresis was performed on 40 samples after bilirubin photodegradation. The bilirubin and serum proteins were determinated respectively by Jendrassik and Grof and biuret methods on Konelab 20i ™ (Thermo Electron Corporation). We found abnormal spreading of the albumin fraction of the anode side wich constitute sometimes an isolated fraction in the traditional area of pre-albumin migration. This fraction varies from 2.0 ± 2.0% (0.0 to 7.3%) or 0.98 ± 1.53 g/L (0 to 5.3 g/L) and it seems to be related to the direct bilirubin since, following overloading sera with a solution of bilirubin, no further fraction was recovered. An average decrease of bilirubin after photodegradation of 58 ± 17% (26-89%) is followed by a decrease in the same order 64 ± 38% (10-100%) of the additional fraction. Acetate cellulose electrophoresis of the same samples showed no variation. The high bilirubin levels seem modify slightly the electrophoretic profile. However the impact of the interference on the interpretation of electrophoretic trace is negligible.

Screening for diabetic nephropathy is usually done by albuminuria/24h and the use of creatinine clearance. The objective of this study was to evaluate the renal function in Type 2 diabetes by using different formulas of creatinine clearance and to assess the contribution of cystatin C; 83 adults with type 2 diabetes (23 men and 60 women) and 83 adult controls (40 men and 43 women) were studied. Biochemical parameters were determinated on Coba 6000™ (Roche diagnostics). Diabetics showed a significant increase in blood glucose, cholesterol, triglycerides, LDLc, the ApoB, Lp(a), urea, uric acid, creatinine and cystatin C and lower HDLc. Cystatin was increased in patients with degenerative complications and in hypertensive patients. We found strong correlations of cystatin C with creatinine (r = 0.9454), urea (r = 0.8999) and uric acid (r = 0.8325). We found a significant exponentially increase of creatinine and cystatin C from one stage to another. Cystatin C has a strong association with MDRD (r = 0.8086) and CG (r = 0.7915) and a low one with creatinine clearance (r = 0.1044). In conclusion, the use of cystatin C for screening and early treatment of incipient diabetic nephropathy appears to be adequate. CG and MDRD formulas still hold their place, in regards to the classical determination of creatinine clearance, to monitor patients.

Bone loss in celiac disease (CD) is important and is associated to increased risk of fractures. The determining factors of this Bone loss and the osteoporosis fracture during this disease remain still unknown. The bone remodeling parameters seem to play it an important role.Through a transverse study including 30 patients with adult CD and 30 witnesses, we estimated bone mineral density (BMD) profile of these patients and determined associated factors to the bone loss.Patients and witnesses benefited from an BMD measure, serum calcium and phosphore, alkaline phosphatasis, parathormone and hydroxyvitamin D dosage, bone remodeling parameters containing the osteocalcin, Propeptide N-terminal of the type I procollagen, BTélopeptide C-terminal ( B-CTX) of the type I procollagen I (bloody and urine CrossLaps). The patients benefited from a malabsorption bilan, a radiological examination of spine and an evaluation of the adhesion to the regime without gluten with a histological control.Our population consists of 3 men (10 %) and 27 women (90 %) with an average age of 30.4 years (19-50 years). The average delay of the diagnosis of the MC is of 46.7 months. The alkaline phosphatases, the P1NP and the bloody crossLaps were more raised at the patient's with regard to the witnesses with respectively p=0.038, p=0.041 and p=0.021. The parathormone was also more raised at the patients but without significant difference 67.8 vs 53.8 ng / l. The DMO is low at 21 patients (70 %) versus 2 witnesses only (6.6 %), with an osteoporosis in 3 patients (10 %) and an osteopenia in 18 patients (60 %). Factors associated to the BMD decline are low body mass index, nulliparity, diagnostic delayto 2 years, the malabsorption syndrome, exaggerated intraepithelial lymphocytosis at the time of the histological control, an increase of bone remodeling parameters notably the alkaline phosphatasis, osteocalcin and bloody CrossLaps. While the BMD is more raised at the patient's having followed gluten regimens during more than 5 years. The age, the sex, the symptomatic character or not of the disease, the parathormone, hydroyviamin D and fractures are not correlated to the BMD profile patients.The bone loss is more frequent during the adult CD than in the general population. His research has to become integrated into the coverage of this disease notably in the presence of risk factors. The absence of correlation between BMD loss and fractures underlines the importance of others factors in determining of bone fragility during this affection.

Objectif : ce travail a pour objectif de preciser le profil sociodemographique des consommateurs de cannabis, ainsi que les caracteristiques et les effets de la consommation. Methodes : notre etude transversale et descriptive a concerne 205 sujets (191 hommes et 14 femmes), âges de 25,9 ± 7,9 ans. La consommation des medicaments psychotropes et/ou de cannabis a ete confirmee par une analyse toxicologique. Resultats : dans notre population d’etude, 61 % des sujets etaient consommateurs de cannabis avec une predominance masculine de 94,4 %. Les consommateurs etaient des adultes jeunes, âges de 25,8 ± 8,8 ans en moyenne, celibataires (81,6 %), de niveau scolaire primaire (62,4 %), ayant une activite professionnelle (72 %) et residant dans des zones urbaines (77,6 %). Au total, 28,8 % avaient des antecedents personnels psychiatriques. L’âge moyen du debut de consommation etait de 20 ans. La consommation associait frequemment l’alcool et le tabac (72 %). La consommation de cannabis etait quotidienne chez 40 % des sujets. La majorite de ceux qui ont consomme de la drogue l’ont fait au cours de reunions entre amis. Dans la plupart des cas, le recours au cannabis etait considere comme un moyen de fuir les problemes (29,3 %), de relaxation (20,2 %), d’experimentation (18,2 %) et de recherche de plaisir (16,7 %). Conclusion : ces donnees suggerent l’importance d’une prevention primaire de l’usage precoce, associee a une prise en charge rapide des personnes engagees tres jeunes dans la consommation de cannabis.

This study aims to investigate the variation of pseudocholinesterase activity (BuChE) in bipolar patients and to explore its relation to the clinical and therapeutic characteristics of this disease. Our study included 105 patients with bipolar disorder and 100 control subjects aged 38.7 ± 12.2 and 36.4 ± 15.7 y, respectively. BuChE was determined by kinetic methods on Cobas Integra 400 plus™. Compared with controls, patients had a significantly higher pseudocholinesterase activity. Moreover, this increase was significantly associated (p = 0.001) with bipolar disorder with sensibility of 58% and specificity of 62% at threshold of 7392 IU/L. There was no significant change in pseudocholinesterase activity in relation to illness episodes and treatment, whereas the lowest values of this activity were seen in euthymic patients and those taking psychotics. Therefore, this activity is a real interest in the biological monitoring of patients as a risk factor for neurodegenerative diseases associated with bipolar disorder. But it would be most useful to evaluate their interest as a predictor of bipolar disorder in patients at risk.

La butyrylcholinesterase (BChE) est une enzyme incriminee dans la genese de differentes affections neurodegeneratives et probablement neuropsychiatriques. Dans ce travail, nous avons etudie les variations de l’activite de cette enzyme chez des patients schizophrenes dans l’objectif de preciser son implication dans la schizophrenie (SZ) et l’interet de la determination de son activite dans cette pathologie. Notre etude cas-temoins a concerne 131 patients schizophrenes âges de 38,0 ± 11,4 ans et 90 sujets temoins âges de 37,1 ± 15,9 ans. L’activite de la BChE plasmatique a ete determinee par une methode cinetique sur l’automate Integra 400 plus™ (Roche diagnostics). L’activite moyenne de la BChE etait significativement plus elevee chez les patients schizophrenes par rapport aux temoins ( p < 0,0001). Elle etait egalement significativement plus elevee dans le sexe feminin et significativement plus basse chez les fumeurs par rapport aux non-fumeurs, aussi bien pour les patients que pour les temoins. Chez les patients schizophrenes, il n’y avait pas de variation significative de l’activite de la BChE en fonction de l’âge, du statut alcoolique, du sous-type clinique de la maladie et de l’anciennete de la maladie. L’activite moyenne de la BChE etait plus elevee chez les patients traites par des antipsychotiques en monotherapie par rapport a ceux traites par une association antipsychotiques et anticholinergiques, sans difference significative ( p = 0,196). Les patients schizophrenes presentent une augmentation de l’activite plasmatique de BChE, qui pourrait etre en relation avec la physiopathologie de la SZ.

This study aims to investigate the prevalence of obesity and overweight and their association with lipid parameters in bipolar patients. Our study included 130 patients with bipolar disorder and 130 control subjects aged respectively 37.9 +/- 12.1 and 37.2 +/- 13.1 years. Obesity was evaluated by body mass index (BMI). Concentrations of total cholesterol, triglycerides, cLDL and cHDL were determined by enzymatic methods and ApoA1, ApoB and Lp(a) by techniques immunoturbidimetric. The prevalence of obesity in patients is 30.1% vs 12.3% in controls. A significant increase in BMI was noted in patients compared with controls regardless of sex and tobacco status and in patients aged less than 35 years and those consumers of alcohol. The majority of obese and overweight patients are treated with valproic acid. We found increase in cholesterol (4.41 +/- 1.02 vs 3.90 +/- 0.98 mmol/L), in cLDL (2.13 +/- 1.09 vs 1.29 +/- 0.56 mmol/L) and in Lp(a) (236 +/- 207 vs 163 +/- 150 mg/L) and decrease in HDLc (0.98 +/- 0.28 vs 1.09 +/- 0.36 mmol/L), more frequent at the obese patients and those presenting an overweight. In conclusion, in bipolar patients, obesity and overweight are frequent and associated with perturbations in lipid profile particularly an increase in total cholesterol, cLDL and Lp(a) and decrease in cHDL that increase the risk of cardiovascular disease.

This study aims at examine the effect of cigarettes smoking on paraoxonase 1 (PON1) activity and lipid profile. Our study included 102 smokers aged 35.5 +/- 16.0 years and 98 non-smokers aged 38.5 +/- 21.9 years. Total cholesterol (TC), triacylglycerols (TG), HDL cholesterol (CHDL) and LDL-cholesterol (cLDL) were determined by enzymatic colorimetric methods. ApoA1 and ApoB and Lp(a) were analyzed by immunoturbidimetry on Konélab 30, PON1 activity was measured by a kinetic method. Plasma CT, TG, cLDL, Lp(a) and ApoB/ApoA1 ratio appeared significantly higher in the smokers when compared to nonsmokers, since cHDL levels were lower. In addition, TG values were significantly higher in subjects smoking more than 30 cigarettes/day as compared to those smoking 5-10 cigarettes/day. We noted a significant decrease of PON1 activity in smokers compared to non smokers (94 +/- 104 vs 158 +/- 133 IU/L), with regression of PON1 activity according number of cigarettes/day. In conclusion, hypertriglyceridemia, low levels of cHDL, high levels of ApoB/ApoA1 and significant decrease of PON1 activity confirm the high risk of cardiovascular diseases in smokers.

The clinical and laboratory characteristics of urolithiasis in Tunisian children have evolved continuously since the 1980s. This retrospective study defines the current status of urolithiasis in children in Tunisia.All 104 children (age: 8-192 months) of our series were hospitalized for urolithiasis. A first-line metabolic, urine and plasma work-up was performed in 96 patients. Physical and chemical analysis of the stones was performed by stereomicroscopy and infrared spectroscopy, respectively. Statistical analysis of the results was performed with SPSS 11.0 software. The Chi-square test was used for comparison of percentages.Our study shows a male predominance of urolithiasis with a sex ratio of 1.53. The clinical features were dominated by urinary tract infections (28.8%). Stones were situated in the upper tract in 75% of cases and the lower tract in 25% of cases. Urine culture was positive in 15 patients. Identification of the crystalline composition showed that whewellite was the most frequent crystalline species in children (80.0%) and infants (57.1%). Ammonium acid urate was more frequent in infants.In this study, we observed changes in the epidemiological characteristics (bladder stones and infection stones) of urolithiasis in children over the last decade in Tunisia. The patient's age is an important factor that must be taken into account during aetiopathogenic work-up.

To define the epidemiological and clinical characteristics of urinary stones in infants, to study the role of stone chemical analysis in the aetiological assessment of urinary stones and to define the various treatment modalities adapted to this age-group.Between 1984 and 2002, 64 infants (age: 5-24 months) were hospitalised for urinary stones. Urine culture was performed in all patients and metabolic assessment was performed in 24 patients. Physicochemical stone analysis was performed by infrared spectrophotometry in 37 patients.Upper tract and lower tract stones were equally prevalent. Urine culture was positive in 48 cases. The micro-organism most frequently isolated was Proteus mirabilis (19 cases). The metabolic assessment was normal in 15 patients and pathological in 9 patients. Infrared spectrophotometry showed that 17 stones were pure. 60 patients were treated surgically, 2 were treated by endoscopy associated with intracorporeal lithotripsy. One patient was treated medically and another patient passed the stone spontaneously while in hospital. No intraoperative or postoperative complication was observed. No recurrence was observed in this series. The mean follow-up is 16 months (range: 6 months to 94 months).The epidemiological profile of urinary stones in infants in Tunisia is situated between that observed in developed countries and that observed in developing countries. In our study, the incidence of metabolic abnormalities appears to be low despite a high rate of consanguinity in Tunisia. This can be largely explained by the absence of an aetiological survey and/or an inadequate survey when it is performed.