Hematologic risk factors for stroke in Saudi children

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 [SCO], 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 SC beta-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.

Prevalence of hypertension in obese and non-obese Saudis

Obesity occurs at a high prevalence in the Saudi population. Studies in literature show that hypertension occurs more frequently in obese individuals. This study was designed to determine the prevalence of hypertension in obese Saudis in comparison with results obtained in non-obese individuals. The screening involved a statistically designed household screening program. Only adults 14-70 years of age were included in the study. Blood pressure [systolic and diastolic] was measured when the individuals were in sitting position and height and weight were used to calculate Body Mass Index. All individuals with Body Mass Index > 30 were classified as obese and hypertension was measured as systolic blood pressure > 140 and diastolic blood pressure > 90 or both. The prevalence of hypertension was calculated in the obese and non-obese group. Chi square analysis was carried out to determine the significance of the difference in prevalence in different groups. In the non-obese males and females the prevalence of hypertension was 4.8% and 2.8%. While in the obese group the prevalence was almost 1.6 times higher in the males [8%] and 3.52 times higher [8%] in the female obese. The results were separated on the basis of the province to which the population belonged and hypertension prevalence was calculated in the obese and non-obese. In each region the prevalence of hypertension was higher in the obese group compared to the non-obese group. Non-obeses females had significantly lower hypertension prevalence than the male in the same province but the hypertension prevalence was higher in the females compared to the male in the obese group. Male in the Eastern, Southern and Western provinces did not show an increased hypertension prevalence in the obese. Since the prevalence of obesity is high in Saudis and since obesity and hypertension occur together and cause serious complications, it is strongly suggested that measures are adopted to decrease prevalence of obesity and its underlying complications. Awareness programs are required at the level of the general public for successful implication of preventive programs

Relationship between obesity, overweight and plasma lipids in saudis

Overweight and obesity occur at a high prevalence in Saudi population. This study was conducted with the aim to determine the plasma lipid levels in Saudi overweight and obese individuals and to compare them to the values obtained in the normal weight groups. A total of 2035 adult Saudis [males: 927; temales: 1108] were included in the study. Height and weight were recorded and Body Mass Index was calculated. Fasting blood glucose, Hb Aie, cholesterol and triglyceride levels were measured. The males and females were grouped into three groups [one] normal weight i.e. Body Mass Index < 25, [two] overweight ie. Body Mass Index 25-29.9 and [three] obese ie. Body Mass Index > 30. The cholesterol and triglyceride levels were compared among the groups. The resuits showed that cholesterol and triglyceride are significantly higher in the overweight and obese groups compared to the normal weight group. The correlation between Body Mass Index and lipids was positive and statistically significant. We conclude that since the prevalence of overweight and obesity is high in Saudis and since overweight and obesity are associated with hyperlipidemias, it is essential to initiate control and prevention programmes in an attempt to reduce the prevalence of overweight and obesity and hence morbidity associated with hyperlipi demie states

Gender-Age-diabetes mellitus relation in Al-Qassim population

This study was conducted in the Al-Qaseem area to determine the prevalence of non- insulin dependent diabetes [NIDDM], insulin dependent diabetes [IDDM] and impaired glucose tolerance [IGT]. Blood samples were collected from 2694 individuals [1145 males; 1549 females] screened during a statistically designed household screening programme and grouped into adult males, adult females and children. The fasting blood sample was extracted and a glucose load was given to each individual. Two hour post-prandial glucose level was estimated and the diagnosis of diabetes and IGT was based on the World Health Organisation [WHO] criteria. Further grouping into IDDM and NIDDM was made on the basis of age of onset of diabetes and mode of treatment. The prevalence of IDDM, NIDDM and IGT in the overall population was 0.15%, 5.23% and 0.63% respectively. Of the 2694 individuals screened 4 had IDDM giving an incidence of around 3 IDDM cases /2000 individuals. In the adult male [> 14 years] the prevalence of NIDDM and IGT was 11.277% and 0.829% respectively while it was 7.50% and 0.719% in the adult females, respectively. When further grouping was done on the basis of age a significant increase was observed in those over the age of 30 years where 19.883% and 1.462% males and 14.839% and 1.075% females had NIDDM and IGT, respectively. This study showed that diabetes is a significant health problem in the adult population of Al-Qaseem. Steps toward improved awareness, control and prevention are essential in order to reduce the prevalence of this metabolic disorder, which is associated with significant morbidity and complications

Bacterial infections and the sickling disorders - a review

Patients suffering from the sickling disorders have an increased susceptibility to bacterial infections which claim a high rate of morbidity and mortality. The most common bacterial infections include pneumonia, meningitis, osteomyelitis, pyelonephritis and general sepsis. The prevalence, site of infection and susceptibility to various organisms varies in the different age groups. Streptococcus pneumoniae, haemophilis influenzae, salmonella species and staphylococcus aureus are among the organisms which are the most common cause of infections both in children and adults with the sickling disorders. Early diagnosis of the sickling disorders in the newborn, proper health care, adequate nutrition, early diagnosis of infection and prompt treatment are some of the factors which have contributed to improve the morbidity and mortality rates in the developed countries. Two strategies adopted to safeguard the susceptible patients against pneumoccocal infection are pneumococcal vaccination and penicillin prophylaxis. This paper reviews the commonly encountered infections, possible defects in the immune system and recently adopted prophylactic measures. Suggestions for improving the survival of patients with the sickling disorders are discussed

Infections in sickle cell disease

Bacterial infections are considered a major cause of morbidity and mortality in patients, particularly children, with sickle cell disease. Infections including pneumonia, meningitis, osteomyelitis, pyelpnephritis and general sepsis are more prevalent in patients with these gentic abnormalities than in normal individuals. Generally, infections are more prevalent in children than in older patients. The most common cause of severe infections in hemoglobinopathies include Diplococcus, staphylococcus, Pneumococcus, Salmonella and Streptococcus. Several investigations have been conducted to determine the possible defects in host defense mechanisms. Functional asplenia, defects in alternate pathway and in opsonic activity and phagocytosis of Streptococci, Staphylococci and slamonella in sickle cell anemia patients are considered important factors predisposing these patients to bacteremia. On the other, hand, a beneficial association has been demonstrated between the sickle cell gene and malaria. The hemoglobin S [Hb S] provides a natural resistance against the malarial parasite resulting in an improvement in fitness and survival over the normal [Hb AA] individuals. This communication reviews infection in sickle cell disease with a comparison results in various populations

Hepatitis B markers in Saudi Arabia: a comparative study in different regions

The Saudi population in different regions of Saudi Arabia was screened for four markers of hepatitis B virus [HBV] using radioimmunoassay techniques. Marked differences were found in prevalence of all markers in the different regions investigated. The prevalence [%] of hepatitis B surface antigen [HB[s]Ag] in the male and female population varied from 4.7% in Riyadh [centeral region] to 32.2% in Jaizan [southwestern region]. The prevalence of anti-HB[s] varied from 32.2% in Riyadh to 69% in Khaiber, and anti-HB[c] varied from 30.5% in Riyadh to 73.5% in Khaiber. These results indicate that HBV infection is endemic in Saudi Arabia, although the different regions vary considerably in cadence of HBV infection. The chronic carrier state is high and a large proportion of the population have been exposed to the infection. The frequency of coexistence of two or more serological markers suggests that the rate of exposure to HBV was high, and a large proportion of the population tested had developed immunity. This communication reports on the prevalence and variations of HBV infection in different parts of Central Arabia. The findings are discussed in light of the prevailing environmental conditions and social habits of the population. It is emphasized that further screening programs are necessary to determine routes of transmission, high risk groups and the causes for such marked variations in the different regions of Saudi Arabia

red cell genetics and environmental interactions: a Tehamat-Aseer profile

The study was carried out in the agricultural strip parallel to the Red Sea in the Westren region of Arabia. The findings were obtained from school children and adult living in villages scattered over an area of about 500 km 2 in Tehamat-Aseer. The sickle cell haemoglobin was detected in about 8-27% of the population. The prevalence of G-6-PD deficiency ranged between 8-15% in different villages. Parasitic infection was found to be a common cause of anaemia. Alpha-Thalassaemia and beta-thalassaemia gene frequencies varied between 20-30% and 10-15%, respectively

Incidence and frequency of hemoglobinopathies and thalassemia in the Northwest sector of Arabia

The main localities of the North-West sector of Saudi Arabia were surveyed for haemoglobinopathies and thalassaemia. The mean values for various haematological parameters were obtained and the effect of these genetic abnormalities on the normal values of haematological parameters was determined and compared with results obtained from expatriates at the Islamic University, Al-Madina

Molecular therapy of sickle cell anemia: the state of art

The complications in sickle cell anaemia result from the reduced solubility of deoxygenated sickle cell haemoglobin [HbS]. The sickling of the red cells is caused by the precipitation of haemoglobins as long, insoluble molecules. The finding that elevated fetal haemoglobin [HbF] levels inhibit the gelation of HbS and results in a benign state of the sickling disease, has initiated interest in drugs that 'switch on' the gamma-chain gene or 'turn off the beta-chain gene. 'Molecular therapy' of sickle cell anaemia is directed at either the inhibition of the gelation process, altering the gene or increasing haemoglobin oxygen affinity. Several substances have been tried in vitro and in vivo as inhibitors of sickling. 5-Azacytidine is one such drug but its use in vivo has been hindered as result of its toxic side-effects. The history of molecular therapy of sickle cell anaemia is outlined and the future is discussed

Glucose 6-phosphate dehydrogenase deficiency: genetic, pathophysiologic and therapeutic aspects

Glucose 6-phosphate dehydrogenase [G6PD] is the first enzyme of the pentose phosphate pathway. It exists in over 250 variants which are divided broadly into five classes on the basis of residual enzyme activity and clinical manifestations. The variants with reduced activity result in G6PD deficiency. This inherited as an X-linked recessive disorder and occurs at a much higher frequency in the male than in the female. G6PD deficient individuals show no clinical abnormality under normal conditions, but acute hemolytic crisis may occur. Several nonhemolytic abnormalities occur as well in G6PD deficients at a higher frequency than in nondeficients. The genetic, pathophysiologic, and therapeutic aspects of G6PD deficiency are presented; and the possibility of genetic counseling, are in blood banks, and benefits of educating the G6PD deficients are discussed

Assessment of the interference of tranquilizing drugs with thyroid function tests

Tranquillizing drugs have limited binding sites on human blood proteins. In abnormal conditions the binding may be affected by a molecule of similar structure, an example of which is thyroid hormone. Consequently, the ratio of free to protein-bound thyroid hormone may be altered because of competition between the hormones and drugs for the same binding sites. Although in vitro assessment showed that Librium [chlordiazepoxide] and Valium [diazepam] can interfere with the binding of thyroxine to serum proteins, interpretation of in vivo effects are equivocal. The present work was aimed at investigating drug interference with methods that employ binding properties of proteins and are commonly used for thyroid hormone determinations. The investigation involved the determination of the effect of drugs, added in vitro, on the measurement of serum thyroxine by competitive protein binding assay [CPBA] and similar commercial kits. These drugs were found to exert different binding properties to serum proteins that exhibited differential effects on T[4] determination. The mode of binding of thyroid hormones and tranquillizers and possible clinical consequence is discussed