Sickle cell disease subphenotypes in patients from Southwestern Province of Saudi Arabia.

Sickle cell disease (SCD) is common in the Eastern and Southwestern (SW) Provinces of Saudi Arabia. We studied 159 patients with SCD to better characterize its phenotype in the SW Province, where patients usually have a HBB haplotype of African origin. All cases had history and examination, chart review, and laboratory testing.

Hematologic risk factors for stroke in Saudi children.

Objective: To explore the hematologic risk factors for stroke in a cohort of Saudi children.

Methods: 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.

Stroke in Saudi children. Epidemiology, clinical features and risk factors.

Objectives: 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.

Methods: 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.

Laparoscopic cholecystectomy: The treatment of choice for cholelithiasis in infancy and childhood.

Twelve consecutive laparoscopic cholecystectomies (LC) were performed between January 1994 and October 1996 at King Khalid University Hospital. In all patients the indication for cholecystectomy was symptomatic gallstones. Among the 12 children, six had sickle cell disease.

Coagulopathy of childhood nephrotic syndrome--a reappraisal of the role of natural anticoagulants and fibrinolysis.

In an attempt to characterise further the coagulopathy of childhood nephrotic syndrome, this study concentrates on simultaneous measurements of the natural anticoagulants [antithrombin III (ATIII), proteins C and S] and the fibrinolytic factors, tissue plasminogen activator (tPA) and plasminogen activator inhibitor (PAI). The study groups consisted of 41 children (ages ranging from 2 to 14 years; median 7.1) in the relapse of nephrosis and 48 children (ages ranging from 3 to 14 years; median 7.

Sickle cell gene in the population of Saudi Arabia.

A comprehensive screening program was initiated in Saudi Arabia in 1982 to determine the frequency of the sickle cell (Hb S) gene in the different regions of Saudi Arabia. Over a period of 10 years 30,055 samples were collected from 36 areas in the five provinces of Saudi Arabia; these were screened using electrophoretic techniques in alkaline and acid pH for the presence of Hb S in heterozygous and homozygous states. The overall prevalence of Hb AS was 7.

Hereditary bleeding disorders in Riyadh, Saudi Arabia.

The result of an eight-year retrospective analysis of patients with hereditary bleeding disorders (HBD) at King Khalid University Hospital, Riyadh, is presented. One hundred and sixty-eight patients referred for investigation for suspected bleeding disorders had bleeding symptoms which fulfilled the criteria for HBD and were categorized as follows: 1) coagulation factor deficiencies: 41 patients had hemophilia A, while 16 had hemophila B; two patients each had factors XI and XII deficiency; four patients each had factors V and VIII deficiency and one patient had factor VII deficiency. There were two patients with dysfibrinogenemias and one with afibrinogenemia.

Nephrotoxicity of low-dose methotrexate in guinea pigs: an ultrastructural study.

The nephrotoxicity of low-dose methotrexate (MTX) and the rescue effect of leucovorin were studied by electron-microscopic examination of the kidney of guinea pigs. One group received MTX as a single weekly dose of 10 mg/kg, i.p.

Ethnic variations in the haemostatic system: comparison between Arabs, Westerners (Europeans and Americans), Asians and Africans.

A wide variety of haemostatic variables were measured in healthy male subjects predominantly blood donors residing in Riyadh, the capital city of Saudi Arabia. Subjects were divided according to ethnic origin: Saudi Arabs n = 487, Westerners (Europeans and Americans) n = 300, South East Asians (Koreans and Filipinos) n = 360, and West Africans n = 82. There were no significant differences in prothrombin time, partial thromboplastin time, thrombin time, reptilase time, plasma fibrinogen, antithrombin, plasminogen and platelet count between Saudis, Westerners and Asians.

Comparison of two types of intravenous immunoglobulins in the treatment of neonatal sepsis.

In a prospective double-blind study, standard intravenous immunoglobulin (IVIG) was compared with an IgM-enriched IVIG in the treatment of neonatal sepsis. The two treatment groups were also compared with matched controls. One hundred and thirty babies (65 in each group) ranging from 0 to 24 days old, 480 to 4200 g in weight and born between 24 and 42 weeks of gestation who had, or were suspected of having, sepsis were given either standard IVIG or IgM-enriched IVIG (250 mg/kg per day) for 4 days in addition to supportive and antibiotic therapy.

Red cell genetic disorders and plasma lipids.

To study the plasma lipid levels in patients with red cell genetic disorders, we investigated 400 normal individuals, 100 sickle cell disease (SCD) patients, 220 sickle cell heterozygotes (Hb AS), and 100 individuals suffering from glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. Whole blood samples were used for the determination of haematological parameters and red cell indices, and plasma was used for the estimation of plasma lipids using Autoanalyser American Monitor 'Parallel'. Haemoglobin types in the haemolysates were separated by electrophoresis and G-6-PD activity was determined using kits from Boehringer Mannheim GmbH.

Platelet Aggregometry - Dose-related Responses to Arachidonic Acid in Childhood Nephrotic Syndrome.

A recent unexpected finding of inhibited platelet aggregation in response to a single (1.64 mmol/l) dose of arachidonic acid (AA), during the relapse of childhood nephrosis, prompted us to assess aggregation in response to multiple doses of AA: 1.64,0.

Is HLA-DRW13 (W6) associated with juvenile myoclonic epilepsy in Arab patients?

In a study of 32 unrelated Arab patients with juvenile myoclonic epilepsy (JME), we compared the frequencies of human leukocyte antigen (HLA) class I and II alleles with those of unrelated healthy controls. A significant difference between the phenotypic frequencies in JME patients and controls was observed for DRW13, the split of DRW6 (37.5 vs 11% of controls).

Glucose-6-phosphate dehydrogenase deficiency and the sickle cell gene in Makkah, Saudi Arabia.

This study was conducted on 689 Saudi males and females living in the Makkah area in the western province of Saudi Arabia. The frequency of severe glucose-6-phosphate dehydrogenase (G-6-PD) deficiency in the male and female populations was 0.055 and 0.

Does G gamma/A gamma ratio and Hb F level influence the severity of sickle cell anaemia.

Sickle cell anaemia (SCA) exhibits significant variations in clinical presentation in different populations for which several genetic factors including SCA-associated alpha- and beta-thalassaemias, G-6-PD deficiency and elevated Hb F level have been implicated as possible ameliorating factors. Saudi Arabia is unique in that mild and severe forms of the disease occur at a high frequency. We investigated the G gamma/A gamma ratio and Hb F level and correlated these values with the severity of SCA.

IgG and IgM antibodies to human parvovirus B19 in the serum of patients with a clinical diagnosis of infection with the virus and in the general population of Saudi Arabia.

A total of 56 samples of serum from 32 patients with a clinical diagnosis of human parvovirus B19 infection were tested for specific immunoglobulin G (IgG) and M (IgM) antibodies by means of the recently available indirect enzyme-linked immunosorbent assay (ELISA) (Parvoscan-B19, Ferring Diagnostica, Sweden). The assay was also used in order to determine the age-specific prevalence of antibodies to the virus in the general population of Saudi Arabia. Specific IgM antibodies were detected in 94% specimens collected 1 week after the onset of illness and could be detected for up to 2 months.

Glucose-6-phosphate dehydrogenase deficiency and sickle cell genes in two regions of western Saudi Arabia.

This study was conducted on 1409 Saudi males and females living in Makkah and Bisha areas in the Western Province of Saudi Arabia to determine the frequency of glucose-6-phosphate dehydrogenase (G-6-PD) deficiency and hemoglobin S (Hb S) genes and to investigate interactions between the two genes. The frequency of sever G-6-PD deficiency was 0.055 and 0.

Pediatrics inpatients at the King Khalid University Hospital, Riyadh, Saudi Arabia, 1985-1989.

A review of admissions into the pediatric wards of the King Khalid University Hospital (KKUH), Riyadh, Saudi Arabia, over a four-year period (1985-1989) indentified perinatal problems, acute respiratory infections, congenital anomalies and diseases of the central nervous system, as the major disorders. With the notable exception of nutritional rickets, manlnutrition was rare. The age distribution showed a preponderance of neonates and infants who represented 42.

Blood proteins C and S in sickle cell disease.

Proteins C and S are vitamin K-dependent proteins with an essential anti-coagulant function. Protein C exists in an inactive form and is activated by a thrombin-thrombomodulin complex. Protein S combines with protein C and forms a stoichiometric complex which regulates coagulation in the presence of calcium.

DNA polymorphism in the beta-globin gene cluster in Saudi Arabs: relation to severity of sickle cell anaemia.

Significant DNA polymorphisms have been reported in the beta-globin gene cluster of epsilon-G gamma-A gamma-psi beta-delta-beta-gene region, in normal (Hb AA) individuals and in patients with sickle cell anaemia (SCA). Investigations of the extent of the DNA polymorphisms in the beta A- and beta S-globin gene cluster using Hind III, Hinc II, Ava II, Xmn I, and Hpa I, revealed several associations with mild SCA. The correlation of the presence (+) or absence (-) of the restriction endonuclease site to clinical severity in patients homozygous for beta S-gene showed that the mild form of SCA was associated mainly (> 90%) with the Xmn I polymorphic site 5' to G gamma, and to a lesser extent with Hinc II polymorphic site 5' to epsilon and in the psi beta-gene, with Hind III polymorphic site in G gamma and Hpa I polymorphic site 3' to the beta-globin gene, while in the severe form of SCA these polymorphic sites were absent in most patients.

Endocrine functions in sickle cell anaemia patients.

In this study, 80 male and female sickle cell patients, aged 4-50 years, with mild (severity index, SI < 6) and severe (SI > or = 6) forms of the disease were investigated). The levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone, cortisol, growth hormone (GH), free thyroxine (T4), and free triiodothyronine (T3) were determined. The results were evaluated and the mean +/- 2 SD values were compared with those obtained in age- and sex-matched normal controls.

Percentile curves for various hematologic measurements at birth in Arab preterm babies of different gestational ages.

Percentile curves were calculated for hemoglobin; hematocrit; total red and white blood cell counts; mean corpuscular volume; mean corpuscular hemoglobin; mean corpuscular hemoglobin concentration; and platelet, neutrophil, band cell, lymphocyte, monocyte, basophil, and eosinophil counts in preterm babies of 24 through 36 weeks' gestation. The curves were derived from mainly Saudi Arabian preterm babies who were born in Riyadh, which is just above sea level. Babies born to mothers with hematologic problems or babies who themselves had any evidence of hematologic disorder, blood loss, or disorders that affect hematologic values, eg, asphyxia, were excluded from the reference population.

Haemostatic measurements in childhood nephrotic syndrome.

Blood coagulation and platelet aggregation were assessed in children with nephrotic syndrome who were divided into the following groups: (1) relapse without treatment: (2) relapse on steroids; (3) early remission; (4) late remission and (5) steroid resistant. The renal histological findings were also recorded. Plasma anti-thrombin III (ATIII) levels were markedly reduced in groups 1 and 2, below normal in group 3 and were normal in groups 4 and 5.