A retrospective comparison of phototherapy need in O-B versus O-A incompatibility in a single Saudi institution.

BACKGROUND: ABO incompatibility is a major risk factor for neonatal indirect hyperbilirubinemia (NIH), requiring treatment. It has been shown that there are racial differences in direct antiglobulin test (DAT) positivity and phototherapy need in the O--B versus (vs) O--A incompatibility. The comparison between the O--B and O--A incompatibility is not well studied in Saudi Arabia. AIMS: We aimed to compare DAT positivity and phototherapy need in O-B vs O-A incompatibility in Saudi Arabia. METHODS: This retrospective cohort study was conducted in one Saudi hospital. We included a convenience sample of neonates born between 01 January 2013 and 31 December 2021. We included healthy neonates admitted to the nursery care unit only, born at≥38 weeks gestation, and had normal G6PD levels. Neonates that had no G6PD level measurement or lost follow-up post-discharge were excluded. The data span was the first 14 days of life. RESULTS: A total of 611 neonates met our inclusion criteria. Positive DAT was more prevalent in the O-B than the O-A incompatibility [43.5% vs 29.2%, p < 0.001). A greater odd of phototherapy need was observed in the O--B vs O-A incompatibility across various strata. Readmission for NIH, use of 360° exposure phototherapy, or intravenous immunoglobulin administration was more prevalent in the O-B than the O-A incompatibility (13.2% vs 5.0%, p < 0.001). A logistic regression analysis revealed that the O-B incompatibility modified the association between DAT positivity and phototherapy need. CONCLUSIONS: The O-B incompatibility had a mediator effect on the relationship between DAT positivity and the need for phototherapy in the study population, which emphasizes that the O-B and O-A are not the same from the NIH point of view.

Readmission for neonatal hyperbilirubinemia in an area with a high prevalence of glucose-6-phosphate dehydrogenase deficiency: A hospital-based retrospective study.

BACKGROUND: Hyperbilirubinemia is one of the most common causes of neonatal readmission to hospital. AIMS: To assess risk factors for hyperbilirubinemia among neonates readmitted for this condition and the ratio of the mean corpuscular hemoglobin concentration (MCHC) to the mean corpuscular volume (MCV). METHODS: We retrospectively studied the clinical and laboratory findings, management and possible risk factors for hyperbilirubinemia in 301 neonates born at ≥35 weeks gestation and readmitted to hospital owing to hyperbilirubinemia over five years. RESULTS: No risk factors for hyperbilirubinemia were identified in 64 (21.3%) neonates, and one or more risk factors were found in 237 neonates (78.7%). The most prevalent risk factor (41.9%) was G6PD deficiency, which occurred in 11 of the 15 neonates with a serum bilirubin level ≥427 µmol/l. A double-volume exchange blood transfusion was performed in two neonate boys in whom G6PD deficiency was the single risk factor for hyperbilirubinemia. One of them developed kernicterus later. The MCHC/MCV ratio of neonates with idiopathic hyperbilirubinemia, unexplained hemolysis, or other risk factors overlapped. CONCLUSIONS: This study confirmed that in an area where G6PD deficiency is prevalent, it is the most common and most severe risk factor for hyperbilirubinemia. This finding supports routine neonatal screening for G6PD deficiency in such areas. The usefulness of determining the MCHC/MCV ratio in the management of hyperbilirubinemia is uncertain.

Natural radionuclides in clay deposits: concentration and dose assessment.

Clays are among the most important industrially used minerals. Three potential clay mineral mining sites in Saudi Arabia were chosen, and 21 clay deposit samples were collected. The activity concentrations (average±standard deviation) of the naturally occurring radioactive materials (NORMs), (238)U, (226)Ra, (232)Th, (228)Ra and (40)K, were 49±20, 47±23, 34±11, 40±20 and 751 Bq kg(-1), respectively. The radiation dose assessments (e.g., absorbed dose rate, nGy h(-1); effective dose equivalent, µSv y(-1); and effective dose rate due to dust inhalation, µSv y(-1)) and hazardous indices (e.g., radium equivalent [Ra-eq] value, external hazardous index [Hex], internal hazardous index [Hin] and representative gamma level [Iγ]) were calculated. The wide variations in the activity concentrations of the NORMs according to sampling region could be due to the origin of the geological formation and the geochemical behaviour of the NORMs. Based on calculated hazardous (external and internal) indices, there were no expected radiological hazardous impacts of using clay deposits as building materials.

Glucocorticoid-related osteoporotic fractures.

INTRODUCTION: This study was conducted to evaluate the prevalence of fractures secondary to steroid use. METHODS: A total of 165 patients (100 male and 65 female) who received glucocorticoid therapy at a dose of 7.5 mg or more, or its equivalent, for more than six months were identified from July 1, 2007 to December 30, 2007. Data extracted included age, gender, dose of glucocorticoid, concomitant diseases, the use of anti-resorptive therapy, calcium and vitamin D supplementation, and the results of bone mineral density (BMD) tests, if performed. Any fragility fractures, the site involved and the treatment administered were also recorded. The data was entered and analysed using the Statistical Package for the Social Sciences. RESULTS: 140 patients had no fractures while 25 (15.2 percent) sustained an osteoporotic fracture. The age (p-value less than 0.5), dose of steroids (p-value less than 0.001) and duration of glucocorticoid therapy (p-value less than 0.001) were significantly higher among patients who sustained fractures. Of these, 12 were male and 13 were female. None of the patients in both groups was started on antiresorptive therapy. The dosage of glucocorticoids was higher among women than men (11.5 versus 24.5 mg/day, p-value is 0.05). The commonest sites of osteoporotic fracture were the spine (44 percent) and proximal femur (24 percent). Eight out of 11 patients had more than one vertebra involved. CONCLUSION: Fractures due to steroid-induced osteoporosis could have been prevented if appropriate measures were taken.

Role of nitric oxide in inflammatory diseases.

Nitric oxide (NO) is a signaling molecule that plays a key role in the pathogenesis of inflammation. It gives an anti-inflammatory effect under normal physiological conditions. On the other hand, NO is considered as a pro-inflammatory mediator that induces inflammation due to over production in abnormal situations. NO is synthesized and released into the endothelial cells by the help of NOSs that convert arginine into citrulline producing NO in the process. Oxygen and NADPH are necessary co-factors in such conversion. NO is believed to induce vasodilatation in cardiovascular system and furthermore, it involves in immune responses by cytokine-activated macrophages, which release NO in high concentrations. In addition, NO is a potent neurotransmitter at the neuron synapses and contributes to the regulation of apoptosis. NO is involved in the pathogenesis of inflammatory disorders of the joint, gut and lungs. Therefore, NO inhibitors represent important therapeutic advance in the management of inflammatory diseases. Selective NO biosynthesis inhibitors and synthetic arginine analogues are proved to be used for the treatment of NO-induced inflammation. Finally, the undesired effects of NO are due to its impaired production, including in short: vasoconstriction, inflammation and tissue damage.

Late hyporegenerative anemia in neonates with rhesus hemolytic disease.

This study was conducted to determine the risk factors of the late hyporegenerative anemia in Rh-isoimmunized infants. Data on 36 infants with rhesus hemolytic disease were analyzed. The mean gestational age and birth weight were 36 +/- 1.3 weeks and 2837 +/- 403 grams respectively. Twenty-seven infants (75%) received between 2 and 8 intravascular intrauterine blood transfusions. Fourteen infants (39%) required simple packed red blood cell transfusions and 11 infants (31%) required exchange blood transfusion in the immediate postnatal period. Thirty infants (83%) developed late anemia and required blood transfusions at a mean postnatal age of 43.3 +/- 15.7 days. Sixty-four percent of infants who had exchange blood transfusions did not develop late anemia, while 92% of infants who did not require exchange blood transfusion developed late anemia, and the difference was statistically significant (P = 0.035). Serum erythropoietin levels were determined in 8 infants immediately before simple transfusion for late anemia. The media serum erythropoietin level was 21.2 mU/ml, ranging between less than 10 to 114.2 mU/ml. We conclude that late hyporegenerative anemia is common among Rh isoimmunized infants, regardless of the intravascular intrauterine transfusion. Exchange blood transfusion was associated with less occurrence of late anemia.

Theophylline concentration following equal doses of intravenous aminophylline and oral theophylline in preterm infants.

Steady-state serum theophylline concentrations following equal doses of intravenous aminophylline and oral theophylline were compared in 30 preterm infants with gestational age of 29.2 +/- 2.9 weeks. The result showed no significant statistical difference between the mean serum concentration of theophylline (8.2 +/- 2.2 micrograms/mL vs. 8.4 +/- 1.9 micrograms/mL; p = 0.483). This indicates that a dose reduction of 20%, which is currently recommended, is not required when changing from intravenous aminophylline to oral theophylline. We conclude that in preterm infants, equal doses of intravenous aminophylline and oral theophylline maintain the same serum theophylline concentration.

The use of phosphodiesterase inhibitor (dipyridamole) to wean from inhaled nitric oxide.

A full-term, male neonate developed persistent pulmonary hypertension, and responded to high-frequency oscillatory ventilation and inhaled nitric oxide (INO). Discontinuation of INO was attempted three times and was followed by severe desaturations due to right-to-left shunt through the patent ductus arteriosus and patent foramen ovale. As a result of this rebound pulmonary hypertension, the neonate was maintained on INO therapy for 6 days. Successful discontinuation was achieved by using the phosphodiesterase inhibitor, dipyridamole. We speculate that during exogenous INO therapy, endogenous nitric oxide was inhibited, thus cyclic guanosine 3',5'-monophophate, the smooth muscle relaxant, was rapidly hydrolyzed. By inhibiting phosphodiesterase, smooth muscle relaxation occurred, and consequently weaning from INO was achieved.

Experimental studies on brucellosis in chickens.

The present study was carried out on 30 one-day old and 50 six-months old chicks in two separate experiments. Exposure of one-day old chickens to Br. abortus showed no apparent clinical signs, although the microorganism was recovered from 2 out of 10 infected cases. 40% of chicks which were exposed to Br. melitensis showed signs of illness 48-72 hours post infection with fatal termination within 12-36 hours after onset of symptoms. The microorganism was isolated from 6 out of 10 infected chicks. Adult chicks, when exposed to Brucella infection showed no clinical signs except a slight decrease in egg-yield among hens infected intraperitoneally with Br. melitensis, although brucella organisms were recovered from droppings, egg-shell, egg-yolk and white, and from internal organs of some chicks. Bacteriological evaluation of diagnostic procedures showed that Rose Bengal and Brucellosis card tests were efficient for the diagnosis of brucellosis in chickens. The brucellin test proved its efficacy when applied in the wattle, better than in wing-folds with a peak of reaction within 48 to 72 hours post inoculation. Brucella organisms isolated from experimentally infected chicks were identical to the original strains used. In droppings of chicks Br. melitensis survived for 48 days at room temperature (12-22 degrees C). Beside the economical losses resulting from infection by Br. melitensis of one-day old chicks, the results obtained assure the significance of infected chicks, their eggs and droppings in disseminating brucellosis for man and animals.