Waleed Tamimi

Imam Muhammad bin Saud Islamic University, Riyadh, Mintaqat ar Riyad, Saudi Arabia

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Publications (15)24.71 Total impact

  • Article: Pubertal characteristics among schoolgirls in Riyadh, Saudi Arabia.
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    ABSTRACT: Puberty is the gradual transition period between childhood and adulthood. Many factors may contribute to the onset of puberty. The objective of the study was to determine the age of onset of secondary pubertal characteristics among Saudi Arabian girls. A cross-sectional study was conducted using a cluster sample design. Seven hundred and twenty-five schoolgirls between the ages of 6 and 16 years from diverse socioeconomic levels were included. During physical examinations, the height and weight of the girls were recorded, and the stages of breast and pubic hair development were determined according to Tanner stages; axillary hair development was determined according to modified stages. The median age at Tanner stage 2 for breast and pubic hair development was 10 years. The median age at stage 2 in modified scales for axillary hair development was 12 years. In conclusion, the median age of the onset of breast development at Tanner stage 2 for Saudi girls in Riyadh is lower than what has been reported in some countries in Europe, South Africa, Turkey and India but similar to girls in Hong Kong, China and white girls in the USA, which may support secular trends of an earlier onset of puberty.
    European Journal of Pediatrics 05/2013; · 1.88 Impact Factor
  • Article: Biomarkers of oxidative stress in women with pre-eclampsia.
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    ABSTRACT: Aim: The potential role of oxidative stress in the pathophysiology of pre-eclampsia has been reported in the literature. There are only a few studies that have investigated changes in malondialdehyde (MDA), vitamin E and total blood glutathione together in pre-eclampsia. Therefore, the aim of this study was to measure the levels of MDA, vitamin E and total glutathione as putative circulatory markers of oxidative stress for the early detection of pre-eclampsia. Patients & methods: In this case-control study, blood samples were collected from 40 pre-eclamptic and 80 normal pregnant females at the department of obstetrics and gynecology at King Abdulaziz Medical City (Riyadh, Saudi Arabia) between February 2009 and January 2010. Circulating markers of oxidative stress were evaluated, including MDA, total glutathione and vitamin E, by high-performance liquid chromatography. Results: Markers of oxidative stress including serum MDA, total glutathione and vitamin E were found to be significantly different in both groups. Conclusion: MDA, vitamin E and blood total glutathione are possible candidate markers to predict pre-eclampsia.
    Biomarkers in Medicine 04/2013; 7(2):229-34. · 0.86 Impact Factor
  • Article: Puberty development among children and adolescents with chronic disease in Saudi Arabia.
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    ABSTRACT: Increasing numbers of children with chronic health conditions are now surviving into adolescence and adulthood because of advancing health care. These chronic health conditions are generally known to impact a child's growth and development, including pubertal development. In Saudi Arabia, chronic diseases are prevalent, yet no reports of pubertal onset and its relation to chronic illness are available. The aim of this study was to explore pubertal development among Saudi children and adolescents with a chronic illness. Cross-sectional study conducted at schools in Riyadh, Saudi Arabia in 2006. Those students whose parents reported that their son/daughter had a chronic illness and/or was taking a long-term medication underwent a physical examination to determine sexual maturity rating and growth parameters. Of 1371 students who participated in the study, 155 (11.3%) had a chronic illness. Of those, 79 (51%) were male, and the mean SD age of all the students was 11.4 (2.4) years. Ninety (58%) students were taking medication for their health condition. Bronchial asthma was reported to be the most common chronic condition (n=66; 42.6%), followed by blood disorders (n=41; 26.5%). Fifty-three (34%) students were overweight or obese. For male gonadal (G) development, the mean age of boys with G stage 2 was 11.7 years; stage 3: 13.5 years; stage 4: 14.1 years; and stage 5: 14.6 years. For female breast (B) development, the mean age of girls with B stage 2 was 10.7 years; stage 3: 11.3 years; stage 4: 12.4 years; and stage 5: 14.1 years. The pubic hair development for both boys and girls was similar to the corresponding gonadal or breast development, respectively. The age of onset of pubertal development for both boys and girls with a chronic illness are within normal limits. The high prevalence of overweight and obesity may contribute to this phenomenon, yet further studies should consider the effects of disease severity and chronicity and medication use as possible confounders.
    Annals of Saudi medicine 07/2012; 32(4):408-11. · 1.07 Impact Factor
  • Article: Age- and Gender-Specific Reference Intervals for Fasting Blood Glucose and Lipid Levels in School Children Measured With Abbott Architect c8000 Chemistry Analyzer.
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    ABSTRACT: Reference intervals for pubertal characteristics are influenced by genetic, geographic, dietary and socioeconomic factors. Therefore, the aim of this study was to establish age-specific reference intervals of glucose and lipid levels among local school children. This was cross-sectional study, conducted among Saudi school children. Fasting blood samples were collected from 2149 children, 1138 (53%) boys and 1011 (47%) girls, aged 6 to 18 years old. Samples were analyzed on the Architect c8000 Chemistry System (Abbott Diagnostics, USA) for glucose, cholesterol, triglycerides, HDL and LDL. Reference intervals were established by nonparametric methods between the 2.5th and 97.5th percentiles. Significant differences were observed between boys and girls for cholesterol and triglycerides levels in all age groups (P < 0.02). Only at age 6-7 years and at adolescents, HDL and LDL levels were found to be significant (P < 0.001). No significant differences were seen in glucose levels except at age 12 to 13 years. Saudi children have comparable serum cholesterol levels than their Western counterparts. This may reflect changing dietary habits and increasing affluence in Saudi Arabia. Increased lipid screening is anticipated, and these reference intervals will aid in the early assessment of cardiovascular and diabetes risk in Saudi pediatric populations.
    Indian Journal of Clinical Biochemistry 04/2012; 27(2):141-6.
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    Article: Etomidate and mortality in cirrhotic patients with septic shock.
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    ABSTRACT: Clinical effects and outcomes of a single dose etomidate prior to intubation in the intensive care setting is controversial. The aim of this study is to evaluate the association of a single dose effect of etomidate prior to intubation on the mortality of septic cirrhotic patients and the impact of the subsequent use of low dose hydrocortisone. This is a nested-cohort study within a randomized double blind placebo controlled study evaluating the use of low dose hydrocortisone in cirrhotic septic patients. Cirrhotic septic patients ≥ 18 years were included in the study. Patients who received etomidate prior to intubation were compared to those who did not receive etomidate for all cause 28-day mortality as a primary outcome. Sixty two intubated patients out of the 75 patients randomized in the initial trial were eligible for this study. Twenty three of the 62 intubated patients received etomidate dose prior to intubation. Etomidate use was not associated with all cause 28-day mortality or hospital mortality but was associated with significantly higher ICU mortality (91% vs. 64% for etomidate and controls groups, respectively; p = 0.02). Etomidate patients who received subsequent doses of hydrocortisone required lower doses of vasopressors and had more vasopressor-free days but no improvement in mortality. In this group of septic cirrhotic patients with very high mortality, etomidate increased ICU mortality. Subsequent use of hydrocortisone appears to have no benefit beyond decreasing vasopressor requirements. The lowest mortality was observed in patients who did not receive etomidate but received hydrocortisone.
    BMC Clinical Pharmacology 12/2011; 11:22. · 1.36 Impact Factor
  • Article: Age- and gender-specific reference intervals for serum lipid levels (measured with an Advia 1650 analyzer) in school children.
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    ABSTRACT: Due to the lack of country-specific norms in Saudi Arabia, age- and gender-specific lipid reference intervals are needed to be established for Saudi children. Blood samples were collected from 1168 children aged 6-16 years: 500 boys (43%) and 668 girls (57%), and were analyzed for cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL). Reference intervals were established by calculating the mean and the 2.5th and 97.5th percentiles. There were significant differences between boys at each Tanner stage with respect to cholesterol (P < 0.001); and HDL (P < 0.0001) but not LDL (P < 0.06) among girls. There were significant differences between boys and girls during puberty with respect to cholesterol (P < 0.0001), HDL (P < 0.0001), and LDL (P < 0.001). There was a significant positive correlation between total cholesterol levels, LDL and HDL levels at all Tanner stages in both genders. In girls, the only significant inverse correlation was at stage I (r=-0.243, P= 0.001); there was no significant correlation at other stages. Unlike children in other developing countries, Saudi children do not have lower serum cholesterol than their Western counterparts. These findings reflect changing dietary habits and increasing affluence in Saudi Arabia. These reference intervals may be used to aid in the early assessment of cardiovascular risk in Saudi pediatric populations.
    Pediatrics International 03/2011; 53(6):814-9. · 0.63 Impact Factor
  • Article: Role of oxidative stress in the pathogenesis of preeclampsia.
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    ABSTRACT: Hypertensive disorders of pregnancy are associated with an increased risk of maternal and fetal morbidity and mortality. The cause and the pathogenesis of the pregnancy-induced syndrome, preeclampsia, is still poorly understood. Published evidence of altered biomarkers for the endothelial dysfunction suggests that the initiating event in preeclampsia is the reduced placental perfusion, which leads to widespread dysfunction of the maternal vascular endothelium. This review focuses on the role of free radicals in generating the oxidative stress taking antioxidants into consideration which tend to overcome it as well as the role of placenta in preeclamptic pregnancy.
    Archives of Gynecology 11/2010; 282(5):469-74. · 0.91 Impact Factor
  • Article: Low-dose hydrocortisone in patients with cirrhosis and septic shock: a randomized controlled trial.
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    ABSTRACT: Recent studies have reported a high prevalence of relative adrenal insufficiency in patients with liver cirrhosis. However, the effect of corticosteroid replacement on mortality in this high-risk group remains unclear. We examined the effect of low-dose hydrocortisone in patients with cirrhosis who presented with septic shock. We enrolled patients with cirrhosis and septic shock aged 18 years or older in a randomized double-blind placebo-controlled trial. Relative adrenal insufficiency was defined as a serum cortisol increase of less than 250 nmol/L or 9 μg/dL from baseline after stimulation with 250 μg of intravenous corticotropin. Patients were assigned to receive 50 mg of intravenous hydrocortisone or placebo every six hours until hemodynamic stability was achieved, followed by steroid tapering over eight days. The primary outcome was 28-day all-cause mortality. The trial was stopped for futility at interim analysis after 75 patients were enrolled. Relative adrenal insufficiency was diagnosed in 76% of patients. Compared with the placebo group (n = 36), patients in the hydrocortisone group (n = 39) had a significant reduction in vasopressor doses and higher rates of shock reversal (relative risk [RR] 1.58, 95% confidence interval [CI] 0.98-2.55, p = 0.05). Hydrocortisone use was not associated with a reduction in 28-day mortality (RR 1.17, 95% CI 0.92-1.49, p = 0.19) but was associated with an increase in shock relapse (RR 2.58, 95% CI 1.04-6.45, p = 0.03) and gastrointestinal bleeding (RR 3.00, 95% CI 1.08-8.36, p = 0.02). Relative adrenal insufficiency was very common in patients with cirrhosis presenting with septic shock. Despite initial favourable effects on hemodynamic parameters, hydrocortisone therapy did not reduce mortality and was associated with an increase in adverse effects. (Current Controlled Trials registry no. ISRCTN99675218.).
    Canadian Medical Association Journal 11/2010; 182(18):1971-7. · 8.22 Impact Factor
  • Article: Iron status parameters in preeclamptic women.
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    ABSTRACT: Evidence of increased oxidative stress due to endothelial dysfunction in preeclampsia has been well established. Increase in the oxidative stress is catalyzed in the presence of free transitional metals. Therefore, the relationship of iron status with preeclampsia was under investigation. The objective of the study was to compare red blood cell (RBC) count, hemoglobin (Hb) concentration, hematocrit (Hct), RBC indices, and iron status parameters in preeclamptic and healthy pregnant women. Blood samples were collected from 40 pregnant females diagnosed as preeclampsia and 80 normal pregnant females at the Department of Obstetrics and Gynecology at King Abdulaziz Medical City, Riyadh, Saudi Arabia between February 2009 and January 2010. We recorded RBC count, Hb concentration, Hct, RBC indices, serum iron and ferritin levels in both the groups. Mean serum iron in preeclampsia group was 23.48 ± 9.05, while 12.2 ± 5.21 in normal group (p <0.05). Similarly, mean serum ferritin concentration in preeclamptic and normal pregnant women were 32.56 ± 11.72 and 19.89 ± 8.86, respectively (p < 0.05). No significant differences were found among RBC count, Hb concentration, Hct, and RBC indices in both the groups. We recommend that any pregnant female with higher serum iron and ferritin concentrations should be further investigated for preeclampsia.
    Archives of Gynecology 10/2010; 284(3):587-91. · 0.91 Impact Factor
  • Article: Monoclonal gammopathy in a tertiary referral hospital.
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    ABSTRACT: Monoclonal gammopathies reflect conditions of plasma B-cell disorders. Our objective was to identify the prevalence and types of these gammopathies in our population. A 10year retrospective study was conducted. Serum and/or urine protein electrophoresis were performed on 6624 samples. Positive bands were further tested by immunofixation (IFE). Homogenous bands were detected in 7% of the patients. IFE method confirmed 6.3% in which 59% were males and 41% were females. The mean age was 64.7 for females and 66.5 for males. The sensitivity and specificity were 91% and 99% respectively. The most common protein was IgG kappa 41%, followed by IgG lambda 19%. Sixty-eight percent of these patients had monoclonal gammopathy of undetermined significance and 14.6% had multiple myeloma. The majority of the studied population had MGUS. This observation is in concord with other western populations. The sensitivity and specificity of protein electrophoresis is diagnostically and reasonably acceptable.
    Clinical biochemistry 03/2010; 43(9):709-13. · 2.02 Impact Factor
  • Article: Cystatin C-based formula is superior to MDRD, Cockcroft-Gault and Nankivell formulae in estimating the glomerular filtration rate in renal allografts.
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    ABSTRACT: There are conflicting reports on the reliability of the various glomerular filtration rate formula in renal allografts, to assess the performance of various glomerular filtration rate formula in estimating renal function of renal allografts. Glomerular filtration rate was measured using an isotope Tc99m DTPA in 97 renal transplant patients and estimated using modification of diet in renal disease, Cockroft-Gault formula, Nankivell, and a cystatin C-based formula. The overall performance of these formula was evaluated by calculating bias, accuracy and precision. Mean age was 39.8 years (-/+ 12.7), body mass index was 26.9 (-/+ 6.3) and serum creatinine was 114.5 micromol/L (-/+ 39.3). The mean measured glomerular filtration rate was 58.1 mL/min (-/+ 25.6). The bias with modification of diet in renal disease was 7.7 (P = .03), with Cockroft-Gault formula it was 3.2 (P = .3), with Nankivell it was 10.3 (P = .0002), and with cystatin C it was 0.31 (P = .9) The precisions (r) for modification of diet in renal disease, Cockroft-Gault formula, Nankivell, and cystatin C were 0.26 (P = .01), 0.26 (P = .01), 0.42 (P = .0001), and 0.60 (P < .0001), respectively. We also investigated the impact of sex, age, body mass index, and glomerular filtration rate on the performance of these 4 formula. The best correlation, highest precision, accuracy, and least bias were seen when using cystatin C. The largest bias was seen when using Nankivell and modification of diet in renal disease formula.
    Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation. 12/2009; 7(4):197-202.
  • Article: Effect of body mass index on clinical manifestations in patients with polycystic ovary syndrome.
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    ABSTRACT: To determine whether there is a correlation between body mass index (BMI) and blood pressure or clinical features such as hirsutism in women with polycystic ovary syndrome (PCOS). In this cross-sectional study, 62 women with PCOS were allocated to one of 3 groups according to a BMI range defining normal weight, overweight, or obesity. Blood pressure, waist-to-hip ratio, Ferriman and Gallwey hirsutism score, and presence of acne were recorded for each participant and the means were compared among groups. The overall mean age was 35.85+/-5.03 years; BMI, 31.91+/-6.40; systolic and diastolic blood pressure, 113.02+/-16.10 mm Hg and 71.79+/-10.04 mm Hg; waist-to-hip ratio, 0.82+/-0.07; and hirsutism score, 3.63+/-4.35. Acne was present in 24 participants. Of these, 8 (33.3%) were overweight and 13 (54.2%) obese. When groups were compared, a progressive and significant increase in systolic and diastolic blood pressure was observed from the normal weight to the obese group. We observed a significant and progressive correlation between BMI and both blood pressure and clinical features in women with PCOS.
    International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics 08/2009; 107(1):54-7. · 1.41 Impact Factor
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    Article: A study on clinical and sonographic features in obese and nonobese patients with polycystic ovary syndrome.
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    ABSTRACT: Polycystic ovary syndrome (PCOS) is an endocrine metabolic dysfunction closely associated with obesity, which predisposes to pregnancy complications. PCOS is a common endocrine disorder affecting 5-10% of the population. It is characterized by chronic anovulation and hyperandrogenism with clinical manifestations of oligomenorrhea, hirsutism and acne. Obese females are at higher risk for metabolic syndrome due to severe hyperandrogenemia, which also leads to high blood pressure. To determine, among patients with PCOS, the correlation of body mass index (BMI) with (1) the clinical manifestations of PCOS and (2) blood pressure. We performed a cross-sectional study of 62 women of reproductive age (29-43 years), who attended the Obstetrics and Gynecology Clinic at King Fahd National Guard Hospital in Riyadh, Kingdom of Saudi Arabia, with the confirmed diagnosis of PCOS. These patients were divided into two BMI groups: nonobese (BMI less than 25 kg/m(2)) and obese (BMI more than 25 kg/m(2)). Patients' waist to hip ratio, acne, hirsutism, and systolic and diastolic blood pressures were also recorded as clinical manifestations in PCOS and compared between the two BMI groups. The mean age of the patients was 35.85 +/- 5.03 years, BMI was 31.91 +/- 6.40 kg/m(2), waist-hip ratio was 0.82 +/- 0.067, Ferriman and Gallway's score for hirsutism was 3.63 +/- 4.35, systolic blood pressure was 113.02 +/- 16.10 mmHg, diastolic blood pressure was 71.79 +/- 10.04 mmHg, and acne was present in 24 cases (38.7%). When the groups were compared according to BMI, a significant increase in systolic and diastolic blood pressures (p = 0.001 and 0.003, respectively) was seen in obese patients, but there was no significant rise in the waist-hip ratio and hirsutism score. We observed a significant and progressive effect of BMI on clinical manifestations and blood pressure levels in patients with PCOS.
    Archives of Gynecology 06/2009; 281(3):467-71. · 0.91 Impact Factor
  • Article: Cerebrospinal creatinine kinase level in children with meningitis.
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    ABSTRACT: The aim of this study is to evaluate the diagnostic value of the enzyme creatine kinase (CK) in the cerebrospinal fluid (CSF) of children with meningitis. CSF samples were collected from seventy one children suspected of having meningitis. The levels of total CK, CK-BB, Glucose, total protein, WBC counts, and culture were determined in the CSF. The cutoff value for total CK in the CSF was defined as 18 U/L. Three cases (4%) of bacterial meningitis and 11 cases (15%) of aseptic meningitis were confirmed by culture. The sensitivity and specificity of total CK CSF level alone to diagnose bacterial meningitis were found to be 33% and 91% respectively. The positive and negative predictive values were found to be 14% and 98% respectively. On the other hand, the sensitivity and specificity of total CK level in aseptic meningitis were found to be 40% and 98% respectively and the positive and negative predictive values were 86% and 94% respectively. The sensitivity and specificity of total protein and glucose in CSF were also calculated. Streptococcus pneumonia and homophiles influenza were the main types identified in our cases. Measuring the total CK level in the CSF may be very useful in diagnosis of meningitis if only combined with other CSF markers. It is not of any much benefit if it is used solely.
    Clinical biochemistry 09/2008; 41(12):1025-7. · 2.02 Impact Factor
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    Article: Expansion of Saudi blood donor pool by better screening and vaccination practices.
    Clinical and Diagnostic Laboratory Immunology 12/2003; 10(6):1159-60. · 2.51 Impact Factor