Publications (25)21.04 Total impact
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Article: The coagulopathy of liver disease: does vitamin K help?
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ABSTRACT: Vitamin K is frequently administered in cirrhotic patients to correct their coagulopathy, but evidence for such practice is lacking. We aimed to assess whether vitamin K administration increases the levels of the vitamin K-dependent factor VII (FVII), protein C, and protein S in patients with different stages of liver dysfunction. Eighty-nine patients were recruited into four groups: group 1 [hepatitis B virus (HBV) inactive carriers, n = 23]; group 2 [chronic HBV and hepatitis C virus (HCV) hepatitis, n = 21]; group 3 (cirrhosis, n = 24); group 4 (hepatocellular carcinoma, n = 21); and a healthy control group (n = 39). A single dose of 10 mg of vitamin K1 was administered subcutaneously to all patients. Prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen, FVII, protein C, total and free protein S, and proteins induced by vitamin K absence (PIVKA)-II (des-gamma-carboxy prothrombin) were measured at baseline and 72 h after vitamin K administration. There was progressive increment in baseline PIVKA-II, and decrements in fibrinogen, FVII, protein C, and protein S across study groups (P < 0.0001). Compared to baseline, vitamin K administration did not affect the measured parameters, whereas TT showed no reduction in any of the groups. Protein C levels declined in group 2, whereas FVII, total and free protein S did not increase in any group, for all parameters. Vitamin K therapy does not cause significant improvements in the majority of coagulation parameters and hence does not seem to be routinely indicated in patients with liver disease.Blood coagulation & fibrinolysis: an international journal in haemostasis and thrombosis 10/2012; · 1.25 Impact Factor -
Article: Platelet aggregation and platelet function analyzer 100 (PFA-100) closure time in camels—a comparative study with humans
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ABSTRACT: Despite the very active coagulation system in camels, there are no previous studies on camel platelet functions. It is our aim to study camel platelet function using aggregometry, Platelet Function Analyzer (PFA100), and flow cytometry. A total of 103 camels, 19 males and 84 females, were studied. Their ages ranged from 5 to 20years (meanSD: 6.44.4years). The results obtained were compared with healthy humans. Platelet aggregometry was undertaken in platelet-rich plasma in response to adenosine diphosphate (ADP), adrenaline, collagen, arachidonic acid, and ristocetin. Camel platelet function in whole blood was also tested using the PFA-100 and by flow cytometry using three human monoclonal antibodies (CD42, CD61, and CD62). Camel platelets failed to respond to arachidonic acid, adrenaline, and ristocetin. However, responses to ADP and collagen were obtained but were less than the human values. The addition of human plasma caused some enhancement of the aggregation responses to adrenaline and collagen but not ristocetin or arachidonic acid. However, the presence of human serum or heparin resulted in a very marked enhancement of the camel platelet aggregation responses to all agonists, except arachidonic acid. PFA-100 closure times of the collagen–ADP and the collagen–epinephrine cartridges were markedly longer than in humans. In the flow cytometry studies, camel platelets failed to respond to any of the human monoclonal antibodies with or without activation by ADP, thrombin, human plasma, or serum. This first study on camel platelet functions uncovered the distinction between camel and human platelet functions. The lack of platelet responses to certain aggregating agonists, their enhancement with human plasma and serum, as well as the prolongation of the PFA-100 closure times, add other unique characteristics to the biology of this interesting creature.Comparative Clinical Pathology 04/2012; 15(1):31-37. -
Article: The antiplatelet activity of camel urine.
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ABSTRACT: For centuries, camel urine has been used for medicinal purposes and anecdotally proclaimed as a cure for a wide range of diseases. However, the apparent therapeutic actions of camel urine have yet to be subjected to rigorous scientific scrutiny. Recent preliminary studies from the authors' laboratory have indicated that camel urine possesses potent antiplatelet activity, not found in human or bovine urines, suggesting a possible role for camel urine in inhibiting platelet function. The goal of the current study was to characterize the antiplatelet activity of camel urine against normal human platelets based on agonist-induced aggregation and platelet function analyzer (PFA-100) closure time. Urine was collected from healthy virgin, pregnant, and lactating camels aged 2-10 years. Platelet-rich plasma (PRP) was prepared from blood collected from healthy individuals' blood into citrated anticoagulant. Agonist-induced aggregometry using donor PRP and PFA-100 closure times in whole blood were carried out in the presence and absence of added camel urine. The responses of platelets to multiple doses of camel urine were also assessed. The experimental procedure was repeated in human and bovine urines. Camel urine completely inhibited arachidonic acid (AA) and adnosine diphosphate (ADP)-induced aggregation of human platelets in a dose-dependent manner. PFA-100 closure time using human whole blood was prolonged following the addition of camel urine in a dose-dependent manner. Virgin camel urine was less effective in inhibiting ADP-induced aggregation as compared to urine from lactating and pregnant camels; however, all three showed comparable inhibitory activity. Neither human nor bovine urine exhibited antiplatelet activity. Camel urine has potent antiplatelet activity against ADP-induced (clopidogrel-like) and AA-induced (aspirin-like) platelet aggregation; neither human nor bovine urine exhibited such properties. These novel results provide the first scientific evidence of the mechanism of the presumed therapeutic properties of camel urine.Journal of alternative and complementary medicine (New York, N.Y.) 08/2011; 17(9):803-8. · 1.69 Impact Factor -
Article: Attitude to blood donation in Saudi Arabia.
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ABSTRACT: The blood donor system in the Kingdom of Saudi Arabia depends on a combination of voluntary and involuntary donors. The aim of this study is to explore the attitudes, beliefs and motivations of Saudis toward blood donation. The study was conducted at the Donor Centers at King Khalid University Hospital (KKUH) Blood Bank and King Saud University Students Health Center, Riyadh. A self-administered questionnaire was distributed to donors (n = 517) and nondonors (n = 316), between February and June 2008. All were males. Ninety-nine percent of the respondents showed positive attitude toward blood donations and its importance for patients care, and object the importation of blood from abroad. Blood donors: Ninety-one percent agree that that blood donation is a religious obligation, 91% think no compensation should be given, 63% will accept a token gift, 34% do not object to donating six times/year and 67% did not mind coming themselves to the donor center to give blood. Nondonors: Forty-six percent were not asked to give blood and those who were asked mentioned fear (5%) and lack of time (16%) as their main deterrents. Reasons for rejection as donors include underweight and age (71%) and health reasons (19%). Seventy-five percent objected to money compensation but 69% will accept token gifts and 92% will donate if a relative/friend needs blood. These results reflect an encouraging strong positive attitude toward blood donation. Further future planning with emphasis on educational/publicity programs and careful organization of donor recruitment campaigns could see the dream of total voluntary nonremunerated blood donations should not take long to be true.Asian Journal of Transfusion Science 07/2011; 5(2):121-6. -
Article: Haemostatic and cytokine changes in gestational diabetes mellitus.
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ABSTRACT: Limited data indicate the existence of a hypercoagulable state and the possible involvement of pro-inflammatory cytokines in the pathogenesis of gestational diabetes mellitus (GDM). To characterise the coagulation inhibitor and cytokine profiles in women with GDM. Two groups of women in the third trimester of pregnancy were studied: GDM (n = 150) and controls: women with normal pregnancy (n = 100); GDM in their first post-delivery day (n = 52). LABORATORY ASSAYS: Plasma fibrinogen, antithrombin (AT), protein C, total and free protein S, interleukins-2, 6 and 8 (IL-2, 6, 8). During pregnancy, the only significant alterations noted were higher levels of body mass index, fibrinogen and total protein S in women with GDM when compared to normal pregnancy. In the post-delivery group, there was further elevation in the levels of plasma fibrinogen and significant drop in the level of total protein S, protein C and AT. Significant elevation of IL-2 and IL-6 levels was recorded only in post-delivery group. In GDM, the only indicator of a tendency towards hypercoagulability is the higher fibrinogen levels as compared to normal pregnancy. This feature along with the higher body mass index and presumed associated insulin resistance suggests that GDM may be a mild form of the metabolic syndrome. The lack of significant change in the levels of pro-inflammatory cytokines do not support the existence of an inflammatory state in GDM.Gynecological Endocrinology 05/2011; 27(5):356-60. · 1.58 Impact Factor -
Article: Transfusion medicine in a developing country - alloantibodies to red blood cells in multi-transfused patients in Saudi Arabia.
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ABSTRACT: Multiple transfusions are frequently complicated by alloimmunization. This retrospective study aims to determine whether alloimmunization could be accounted for by racial differences between donors and recipients. The development of alloantibodies were determined in 68 multi-transfused patients (thalassaemia, n=38) and (sickle cell anemia, n=30). The overall frequency of alloantibody formation in our patients is 22.06%. Thirteen patients received blood from the same ethnic group (Arab) and none developed antibodies, while of 47 patients who received multi-ethnic blood, 10 developed alloantibodies. Alloantibodies formation can be reduced by limiting the transfusion of RBC, collected from donors of the same ethnic origin.Transfusion and Apheresis Science 11/2008; 39(3):199-204. · 1.25 Impact Factor -
Article: Effects of heat on camel platelet structure and function-a comparative study with humans.
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ABSTRACT: Camels and many other desert animals are uniquely adapted to conserve water and other fluids in order to survive intense heat for long periods. Earlier studies have suggested that human platelets may be the trigger for the coagulopathy involved in heat prostration and stroke. The present study has compared the resistance of camel and human platelets to heat in order to see if they might help to protect camels from the effects of high body temperature for prolonged periods. The findings demonstrate that camel platelets are significantly less sensitive to heat than human platelets. Temperatures (43 degrees C-45 degrees C) that cause human cells to undergo marked structural alterations and lose their ability to spread and aggregate have no effect on camel platelets. Even higher temperatures (50 degrees C) that destroy human platelets have minor effects on camel cells and do not seriously compromise their function. Temperatures of 55 degrees C do destroy camel platelets and their functional capability. The resistance of camel platelets to heat may help protect camels from the effects of extreme body temperature and dehydration, which are everyday conditions in the desert.Platelets 06/2008; 19(3):163-71. · 1.85 Impact Factor -
Article: The ultrastructure of camel blood platelets: a comparative study with human, bovine, and equine cells.
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ABSTRACT: Previous studies indicated that the camel has a very active haemostatic mechanism with a short bleeding time and thrombocytosis. However, platelet function, when tested by agonist-induced aggregation and PFA 100 closure time, showed marked inhibition compared to humans. Since camels are also far more resistant to long exposure to excessive heat and high body temperature than humans, it seemed worthwhile to explore fundamental morphological differences between human and camel platelets and those from other species. The present study has examined the ultrastructure of camel platelets and compared them with the fine structures of human, bovine and equine thrombocytes. Camel platelets, like bovine and equine cells, are discoid in shape and about two-thirds the size of human platelets. A circumferential coil of microtubular supports the disk-like form of camel platelets. Their cytoplasm, like bovine and equine platelets, is filled with alpha granule twice as large as those in human platelets, but lacking the organized matrix of equine alpha granules. Dense bodies are present in camel platelets with whip-like extensions not present on bovine or equine thrombocytes, but found on occasional human platelet dense bodies. Camel platelets, like bovine and equine thrombocytes, lack an open canalicular system (OCS) and must secrete granule products by fusion with the cell wall rather than an OCS. Future studies will determine if the differences in ultrastructural anatomy protect camel platelets from heat more than human thrombocytes.Platelets 03/2008; 19(1):51-8. · 1.85 Impact Factor -
Article: Tissue factor pathway inhibitor in childhood nephrotic syndrome.
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ABSTRACT: It is now recognised that the extrinsic tissue factor pathway is the main trigger to the coagulation system in vivo. Its main inhibitor, tissue factor pathway inhibitor (TFPI), has never been studied in childhood nephrotic syndrome. The aim of the study was to monitor the level of TFPI in childhood nephrotic syndrome. One hundred and thirty-nine nephrotic children were classified into the following groups: group 1 (n=25), in relapse and receiving no treatment; group 2 (n=37), in relapse but receiving steroid treatment; group 3 (n= 45), in early remission and on steroids; group 4 (n=24), in established remission and receiving no steroids; group 5 (n=8), steroid-resistant. The controls (n=84) were healthy and age-matched. There was significant elevation of total TFPI levels in groups 1 and 2 and 3; levels were comparable to those of the healthy controls in group 4. The highest levels of total TFPI were recorded in group 5. Like total TFPI, the levels of the free form of TFPI showed a statistically significant increase in groups 1, 2, 3 and 4, when compared with levels in healthy controls. The highest levels of free TFPI were recorded group 5. We concluded that the elevated levels of both the total and free TFPI in various phases of nephrotic syndrome add another natural anticoagulant mechanism, which will attenuate the hypercoagulability of childhood nephrotic syndrome.Pediatric Nephrology 07/2006; 21(6):771-7. · 2.52 Impact Factor -
Article: Study project on stroke in Saudi children. Conclusions, recommendations and acknowledgements.
Saudi medical journal 04/2006; 27 Suppl 1:S108-10. · 0.52 Impact Factor -
Article: Moyamoya syndrome as a risk factor for stroke in Saudi children. Novel and usual associations.
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ABSTRACT: To report on moyamoya syndrome (MMS) as a risk factor for stroke in a prospective and retrospective cohort of Saudi children. The usual and novel associations of MMS in this cohort will also be described. Children with stroke were evaluated at the Division of Pediatric Neurology at King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, Kingdom of Saudi Arabia during the periods July 1992 to February 2001 (retrospective study) and February 2001 to March 2003 (prospective study). Investigations for suspected cases included hemostatic assays, biochemical, and serological tests. Neuroimaging included CT, MRI, magnetic resonance angiography (MRA), single photon computerized tomography (SPECT) brain scan and conventional cerebral angiography. Moyamoya syndrome was the underlying risk factor for stroke in 6 (5.8%) of the 104 children (aged one month to 12 years). They were 4 females and 2 males. Their first cerebral ischemic event occurred at a mean age of 45 months (median = 44 months, range 17-66 months). In all 6 cases, MMS was associated with an underlying hematologic abnormality or other diseases. Protein C deficiency was identified in one girl and protein S deficiency in another. Two patients had respectively, sickle cell disease (SCD) and sickle cell-beta-thalassemia (S beta-thalassemia), which had been associated in the latter with membranous ventricular septal defect. Adams-Oliver syndrome (AOS, OMIM 100300) was associated with MMS in an 18-month-old girl. A 4-year-old boy had wrinkly skin syndrome (WSS, OMIM 278250) phenotype. The association of MMS and protein C deficiency was first reported in this cohort of patients, whereas the association of the syndrome with WWS and AOS has not, hitherto, been described. The 3 patients who had MMS associated with protein C deficiency, SCD, and AOS underwent successful revascularization surgery in the form of encephaloduroarteriosynangiosis. Moyamoya syndrome constitutes an important risk factor of stroke in Saudi children. Comprehensive clinical evaluation and investigations, including screening for thrombophilia and neuroimaging studies, are required for the primary diagnosis of the disease and for unraveling other diseases associated with MMS. This will help in managing these patients and in guiding genetic counseling for their families.Saudi medical journal 04/2006; 27 Suppl 1:S69-80. · 0.52 Impact Factor -
Article: Stroke due to mitochondrial disorders in Saudi children.
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ABSTRACT: To report on the clinical and biochemical features of patients who presented with stroke due to mitochondrial disorders amongst a prospective and retrospective cohort of Saudi children. Children, who presented with stroke, were evaluated at the Division of Pediatric Neurology, or admitted to King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, Kingdom of Saudi Arabia, during the periods July 1992 to February 2001 (retrospective study) and February 2001 to March 2003 (prospective study). Open muscle biopsies were obtained from patients suspected to have mitochondrial disorders, and examined using conventional histological and histochemical techniques. Biochemical, molecular pathological investigations, or both, of muscle could be arranged for only some of the patients. Mitochondrial disorders were the underlying risk factor for stroke in 4 (3.8%) of 104 children (aged one month to 12 years). Three patients (one male and 2 females) had Leigh syndrome (LS) and one had mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS). At the time of stroke, the 3 children with LS were 11 months, 15 months, and 7 years old. They presented with psychomotor regression and seizures. Muscle histology and histochemistry showed mild non-specific changes but no ragged red fibers. Biochemical analysis of muscle (in one patient) revealed deficiency of pyruvate dehydrogenase complex. Analysis of mitochondrial DNA (mtDNA), [the other 2 patients] was negative for the 2 point mutations (T-G and T-C) at nucleotide position 8993, and for two T-C point mutations (at positions 8851 and 9176 of the ATPase 6 gene) that have been described in patients with LS. The girl with MELAS syndrome presented with a stroke-like episode at the age of 29 months and had focal brain lesions in the medial aspect of the left occipital and temporal lobes, and in the posteromedial aspect of the left thalamus, which resolved within 7 weeks. She had raised cerebrospinal fluid lactate but no ragged red fibers on muscle histochemistry. Biochemical assay of muscle homogenate showed reduction in respiratory chain complexes I, III and IV. Mutation screening of mtDNA at nucleotides 3243 (tRNA(Leu(UUR))) and 8344 (tRNA(Lys)) was negative. Mitochondrial disorders constitute a risk factor for stroke in Saudi children. However, demanding and highly specialized investigations are needed to confirm the diagnosis. These are better performed at supraregional centers where facilities for clinical, biochemical and molecular work-up are available.Saudi medical journal 04/2006; 27 Suppl 1:S81-90. · 0.52 Impact Factor -
Article: Outcome of stroke in Saudi children.
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ABSTRACT: To report on the prognosis, neurologic outcome, and recurrences of stroke in Saudi children. We evaluated a cohort of 104 Saudi children with stroke at the Division of Pediatric Neurology at King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, Saudi Arabia from July 1992 to February 2001 (retrospective study) and February 2001 to March 2003 (prospective study). We analyzed the salient clinical, neuroimaging, neurophysiological, neuropsychological and laboratory data following retrieval from a specialty designed comprehensive protocol. Of the 104 children in the cohort (aged one month to 12 years), 5 (4.8%) died during the study period and 9 (8.7%) were lost to follow-up. The mean duration of follow-up for the remaining 90 children was 40 months (median 33 months). Recovery was judged complete in 6 (6.7%) of these 90 children. We detected residual hemiparesis (irrespective of its effect on daily functions) in 73 (81%) and this was combined with other motor deficits in 45 children (50%). Forty-one children (46%) had residual dysphasia or language deficits, whereas 45 (50%) were judged to have had cognitive deficit. Psychometry revealed an abnormal intelligence quotient test (<70) in 19 of 26 (73%) children. Other neurologic sequelae included epilepsy in 52 (58%), recurrent headaches in 13 (14%) and hydrocephalus in 4 (4.4%) patients. Six of the 95 (6.3%) children, who were ascertained to have died or kept their follow-up, had one or more recurrences, one month to 5 years after the initial stroke (median 23 months). Patients who had recurrent strokes were significantly more likely to be the product of consanguineous marriages (p=0.04). Regarding the group of 23 children with perinatal stroke, neither deaths nor recurrences occurred during the follow-up period. However, 20 (87%) of them had significant delays in their developmental milestones. The toll of stroke in Saudi children is demanding, with most children demonstrating persistent neurologic or cognitive deficits. Primary prevention for recurrences is feasible through informed genetic counseling.Saudi medical journal 04/2006; 27 Suppl 1:S91-6. · 0.52 Impact Factor -
Article: Cardiac diseases as a risk factor for stroke in Saudi children.
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ABSTRACT: To ascertain the role of cardiac diseases as a risk factor for stroke in a cohort of Saudi children who were evaluated in a retrospective and prospective study. Children with cardiac diseases were identified from within a cohort of 104 Saudi children who presented with stroke. They were seen as inpatients in the Pediatric Wards or evaluated at the Outpatient Clinics of the Division of Pediatric Neurology (DPN), and the Division of Pediatric Cardiology at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia during the periods July 1992 to February 2001 (retrospective study) and February 2001 to March 2003 (prospective study). A comprehensive form for clinical, neuroimaging, neurophysiological and laboratory data retrieval was designed and completed for each patient. Cardiac evaluation included 12-lead ECG and serial echocardiograms. Cardiac catheterization and 24-hour ambulatory ECG (Holter) were conducted on clinical discretion. Cardiac diseases were the underlying risk factor for stroke in 6 (5.8%) of the 104 children (aged one month to 12 years). The patients (4 males and 2 females) were evaluated at the DPN at a mean age of 5.3 years (range = 1-8 years; median 6.5 years). Onset of stroke was at a mean age of 34 months (range = 4 months-8 years; median = 30 months). Five patients had stroke in association with congenital heart disease (CHD), whereas the sixth had restrictive cardiomyopathy. The identified CHD consisted of membranous ventricular septal defect in a 5-year-old boy who had moyamoya syndrome and sickle cell beta(0)-thalassemia, asymptomatic patent ductus arteriosus (PDA) in a 17-month-old girl, atrioventricular canal defect and PDA in an 8-year-old boy who also had Down syndrome, partial anomalous pulmonary venous drainage in a one-year-old boy, and Tetralogy of Fallot in an 8-year-old boy. The latter patient developed hemiparesis secondary to a septic embolus, which evolved into brain abscess involving the right fronto-parietal region. This was successfully managed surgically. The sixth patient was an 8 1/2-year-old girl who had hemiparesis and complex partial seizure in association with restrictive cardiomyopathy. Serial echocardiograms depicted resolution of the cardiac abnormalities within 5 years and subsequent normal findings. Cardiac diseases, as a group, constitute a significant risk factor for stroke in Saudi children. Early diagnosis of these diseases is important to prevent further recurrences of stroke, and because some of them are potentially curable.Saudi medical journal 04/2006; 27 Suppl 1:S61-8. · 0.52 Impact Factor -
Article: Infectious and inflammatory disorders of the circulatory system as risk factors for stroke in Saudi children.
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ABSTRACT: To report on the role of infectious and inflammatory disorders as risk factors for stroke in a prospective and retrospective cohort of Saudi children. Children, who presented with stroke, were evaluated at the Division of Pediatric Neurology or admitted to King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, Kingdom of Saudi Arabia during the periods July 1992 to February 2001 (retrospective study) and February 2001 to March 2003 (prospective study). Investigations for suspected cases included hemostatic assays, microbiological and serological tests. Neuroimaging included cranial CT, MRI, magnetic resonance angiography (MRA), magnetic resonance venography (MRV) and single photon emission computed tomography (SPECT) brain scan. Of the 104 Saudi children with stroke, seen during the combined study periods of 10 years and 7 months, infectious and inflammatory disorders of the circulatory system were the identified risk factor in 18 (17.3%). Five children had stroke following acute bacterial meningitis at ages ranging between 5-21 months. The causative organism was identified in 3 of them and consisted of Haemophilus influenzae (in a 5-month-old girl), Streptococcus pneumoniae (in a 21-month-old girl complicated by subdural empyema and sinovenous thrombosis), and Staphylococcus aureus in a 6-month-old boy who had an underlying chronic granulomatous disease. Unspecified meningitis/meningoencephalitis affected 4 patients, whereas 3 children had an underlying congenital infection as a cause for their stroke. Two of the latter 3 children were diagnosed to have congenital toxoplasmosis, and the third had congenital rubella syndrome. Two girls had stroke following septicemia at ages of one and 2 months. Neurobrucellosis caused stroke in 2 boys at the ages of 4 1/2 and 4 years. In both patients, neuroimaging revealed lacunar and other infarcts involving mainly the deep cerebral nuclei, secondary to occlusion of small penetrating end arteries. Two patients presented with cerebrovascular disease following systemic lupus erythematosus. These were a 12-year-old girl and a 5-year-old boy. Several of the infectious diseases that caused stroke in this cohort of Saudi children are potentially preventable through childhood immunization programs or other maternity health programs. In particular, immunogenic conjugate vaccines against the 3 most common organisms causing acute bacterial meningitis (Haemophilus influenzae type b, Neisseria meningitidis and defined serotypes of Streptococcus pneumoniae) are needed to protect the young (<2 years) who are mostly affected.Saudi medical journal 04/2006; 27 Suppl 1:S41-52. · 0.52 Impact Factor -
Article: Hematologic risk factors for stroke in Saudi children.
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ABSTRACT: To explore the hematologic risk factors for stroke in a cohort of Saudi children. We evaluated children at the Division of Pediatric Neurology at King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, during the periods July 1992 to February 2001 (retrospective study) and February 2001 to March 2003 (prospective study). Investigations for suspected cases included neuroimaging, transcranial Doppler (TCD) for cases of sickle cell disease (SCD), and Duplex scan. Hemostatic assays included coagulation screening tests, tests of thrombin generation and fibrinolysis, coagulation inhibitors, and activated protein C resistance. During the study period, 104 Saudi children (aged one month to 12 years) with stroke were seen. The mean age of the cohort was 27.1 months (SD = 39.3 months) and median was 6 months. Ischemic strokes accounted for the majority of cases (76%). A major risk factor was identified in 93 of 104 cases of stroke (89.4%). Hematologic disorders were the most common (46.2%), followed by prothrombic disorders (31.7%); microcytic hypochromic anemia (26%); sickle cell disease (SCD), or SCbeta(0)-thalassemia, (11.5%), and factor IX deficiency (2.9%). Raised anticardiolipin antibodies (13/49, 26.5%) was the most frequent abnormality. Deficiencies of the natural anticoagulants (protein S, protein C and antithrombin III) were as follows: protein S (15/70, 21.4%); protein C (15/70, 21.4%) and combined deficiency of 2 or more inhibitors (9/70, 12.9%). Activated protein C resistance has not been detected. Contrary to the findings of previous studies from Saudi Arabia, SCD is a common risk factor and is severe, as it resulted in multiple strokes. Moyamoya syndrome was diagnosed in 2 patients with SCD, one of whom had revascularization surgery (encephaloduroarteriosynangiosis). Assessment of children with SCD at risk of stroke was helped by the introduction of TCD followed by neuroimaging, using MRI and magnetic resonance angiography. The study strongly highlights the importance of prothrombotic disorders and the severe phenotype of SCD as risk factors for stroke in Saudi children.Saudi medical journal 04/2006; 27 Suppl 1:S21-34. · 0.52 Impact Factor -
Article: Perinatal stroke in Saudi children. Clinical features and risk factors.
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ABSTRACT: To describe the clinical features and presentations of perinatal stroke in a prospective and retrospective cohort of Saudi children and ascertain the risk factors. Patients with perinatal stroke were identified from within a cohort of 104 Saudi children who were evaluated at the Division of Pediatric Neurology at King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, Saudi Arabia from July 1992 to February 2001 (retrospective study) and February 2001 to March 2003 (prospective study). Neuroimaging for suspected cases of stroke consisted of cranial CT, MRI, or both. During the study period, 23 (22%) of 104 children (aged one month to 12 years) were diagnosed to have had perinatal stroke. The male:female ratio was 1.6:1. Ten (67%) of the 15 children who had unilateral ischemic involvement had their lesion in the left hemisphere. The presentation of the ischemic result was within 24-72 hours of life in 13 (57%) patients, and in 6 children (26%), motor impairment was recognized at or after the age of 4 months. Nine children (39%) had seizures at presentation. Pregnancy, labour, and delivery risk factors were ascertained in 18 (78%) cases. The most common of these included emergency cesarean section in 5 cases, and instrumental delivery in another 5. Screening for prothrombotic risk factors detected abnormalities in 6 (26%) patients on at least one test carried out between 2 months and 9 years of age. Four children (17%) had low protein C, which was associated with low protein S and raised anticardiolipin antibodies (ACA) in one patient, and low antithrombin III in another. Low protein S was detected in a 42-month-old boy. The abnormality in the sixth child was confined to raised ACA. The present study highlights the non-specific features by which stroke presents during the neonatal period. The data are in keeping with the potential role for inherited and acquired thrombophilia as being the underlying cause. However, the high prevalence of additional acquired antenatal and perinatal risk factors support a multifactorial disorder.Saudi medical journal 04/2006; 27 Suppl 1:S35-40. · 0.52 Impact Factor -
Article: Congenital and genetic cerebrovascular anomalies as risk factors for stroke in Saudi children.
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ABSTRACT: To explore the role of and report on congenital and genetic cerebrovascular anomalies as risk factors for stroke in a prospective and retrospective cohort of Saudi children. Children with stroke were evaluated at the Division of Pediatric Neurology (DPN), or were seen as inpatients in the Pediatric Wards at King Khalid University Hospital (KKUH), Riyadh, Kingdom of Saudi Arabia during the periods July 1992 to February 2001 (retrospective study) and February 2001 to March 2003 (prospective study). Stroke work-up for each suspected case included hemostatic assays, serological, biochemical and neurophysiological tests. Neuroimaging modalities included routine skull x-rays, CT, MRI, magnetic resonance angiography (MRA) and conventional cerebral angiography. Of 104 children with stroke, congenital and genetic cerebrovascular anomalies were the underlying risk factor in 7 (6.7%). The patients were evaluated at the DPN at a mean age of 66 months (range = 8 months to 11 years, median = 6 years); and they had stroke at a mean age of 48 months (range = 2 months to 10 years, median = 8 months). Four patients had stroke in association with neurocutaneous syndromes. Two had Sturge-Weber syndrome (SWS), one had Klippel-Trenaunay syndrome associated with SWS, and the fourth had neurofibromatosis type 1. Two patients had intracranial hemorrhage secondary to ruptured aneurysm. A girl (aged 9 years and 4 months) had left posterior cerebral artery aneurysm. She was diagnosed to have autosomal dominant polycystic kidney disease following renal ultrasonography. She died 5 months later despite surgical intervention (clipping of aneurysm). The second child was an 8-month-old boy who presented with subarachnoid and intraventricular hemorrhage (IVH) following ruptured anterior communicating artery aneurysm. He recovered with no residual symptoms following successful clipping of the aneurysm. Arteriovenous malformation (AVM) caused IVH in a 7-year-old boy who reported to hospital 5 hours after onset of headache, vomiting, drowsiness, and dizziness. Following drainage of the IVH and stabilization of the patient, the AVM was successfully embolized 6 weeks later. As a group, congenital and genetic cerebrovascular anomalies constitute a significant risk factor for stroke in Saudi children. Recognition of these diseases is important since some are treatable and because other family members may be at risk.Saudi medical journal 04/2006; 27 Suppl 1:S53-60. · 0.52 Impact Factor -
Article: Diagnostic approach and management strategy of childhood stroke.
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ABSTRACT: Prompt recognition and early intervention, with pertinent management and medication, may reduce subsequent neurologic deficits in stroke, which constitutes a devastating event in children. This is due to the tasking and demanding consequences including death or residual neurological deficits, which may last for many decades, in over 60% of survivors. Evidence-based treatment for children with stroke is still lacking, reflecting scarcity in baseline epidemiological data on pediatric stroke, the multitude of underlying risk factors, and the ethical and practical challenges incurred in conducting clinical trials. Based on the experience we gained from a combined prospective and retrospective study on childhood stroke (covering 10 years and 7 months and involving a cohort of 104 Saudi children), a diagnostic algorithm, which outlines the approach to a child with suspected stroke/cerebrovascular lesion, was designed. This algorithm might also be of use for managing other children with stroke from the Arabian Peninsula and Middle Eastern Region with similar demographic, socioeconomic, and ethnic backgrounds. Underlying risk factors, which need special attention, include thrombophilia and hypercoagulable states and sickle cell disease (SCD), which contrary to previous studies from Saudi Arabia, were found to constitute a common risk factor with severe manifestations. Other risk factors include infections (especially neurobrucellosis), cardiac diseases, and hypernatremic dehydration. Recognition of an identifiable syndrome or inherited metabolic cause may unravel an underlying cerebrovascular disease. This is particularly important in this region, given the large pool of autosomal recessive diseases and the high rate of consanguinity. In the evaluation of a suspected case of stroke, important imaging modalities include cranial CT, MRI (including diffusion-weighted images), magnetic resonance angiography (MRA), magnetic resonance venography (MRV) and conventional angiography. Transcranial Doppler sonography of the intracranial vessels and Duplex scan of the neck are valuable modalities for detecting large vessel vasculopathy, which occur in SCD, moyamoya syndrome, arterial dissection, and stenosis. Antithrombotic drugs are increasingly being used in the acute phase of childhood ischemic stroke. These include unfractionated heparin, low-molecular-weight heparins, aspirin or warfarin, or both. Specialized stroke care and follow-up are needed for children with stroke, as well as their families.Saudi medical journal 04/2006; 27 Suppl 1:S4-11. · 0.52 Impact Factor -
Article: Stroke in Saudi children. Epidemiology, clinical features and risk factors.
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ABSTRACT: To describe the epidemiology and clinical features of stroke in a prospective and retrospective cohort of Saudi children and ascertain the causes, pathogenesis, and risk factors. The Retrospective Study Group (RSG) included children with stroke who were evaluated at the Division of Pediatric Neurology, or admitted to King Khalid University Hospital, College of Medicine, King Saud University, Riyadh, Kingdom of Saudi Arabia during the period July 1992 to February 2001. The Prospective Study Group (PSG) included those seen between February 2001 and March 2003. During the combined study periods of 10 years and 7 months, 117 children (61 males and 56 females, aged one month-12 years) were evaluated; the majority (89%) of these were Saudis. The calculated annual hospital frequency rate of stroke was 27.1/100,000 of the pediatric (1 month-12 years) population. The mean age at onset of the initial stroke in the 104 Saudi children was 27.1 months (SD = 39.3 months) and median was 6 months. Ischemic strokes accounted for the majority of cases (76%). Large-vessel infarcts (LVI, 51.9%) were more common than small-vessel lacunar lesions (SVLL, 19.2%). Five patients (4.8%) had combined LVI and SVLL. Intracranial hemorrhage was less common (18.2%), whereas sinovenous thrombosis was diagnosed in 6 (5.8%) patients. A major risk factor was identified in 94 of 104 (89.4%) Saudi children. Significantly more hematologic disorders and coagulopathies were identified in the PSG compared to the RSG (p=0.001), reflecting a better yield following introduction of more comprehensive hematologic and coagulation laboratory tests during the prospective study period. Hematologic disorders were the most common risk factor (46.2%), presumed perinatal ischemic cerebral injury was a risk factor in 23 children (22.1%) and infectious and inflammatory disorders of the circulatory system in 18 (17.3%). Congenital and genetic cerebrovascular anomalies were the underlying cause in 7 patients (6.7%) and cardiac diseases in 6 (5.8%). Six patients (5.8%) had moyamoya syndrome, which was associated with another disease in all of them. Inherited metabolic disorders (3.8%) included 3 children with Leigh syndrome and a 29-month-old girl with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes. Systemic vascular disease was a risk factor in 3 children (2.9%) including 2 who had hypernatremic dehydration; and post-traumatic arterial dissection was causative in 3 cases (2.9%). Several patients had multiple risk factors, whereas no risk factor could be identified in 11 (10.6%). Due to the high prevalence and importance of multiple risk factors, a comprehensive investigation, including hematologic, neuroimaging and metabolic studies should be considered in every child with stroke.Saudi medical journal 04/2006; 27 Suppl 1:S12-20. · 0.52 Impact Factor
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2002–2011
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King Saud University
- College of Medicine
Riyadh, Mintaqat ar Riyad, Saudi Arabia
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2008
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King Khalid University Hospital
Riyadh, Mintaqat ar Riyad, Saudi Arabia
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