Glucose-6-phosphate dehydrogenase deficiency and homozygous sickle cell disease in Jamaica

Co-Occurrence of G6PD Deficiency and SCT among Pregnant Women Exposed to Infectious Diseases

During pregnancy, women have an increased relative risk of exposure to infectious diseases. This study was designed to assess the prevalence of the co-occurrence of glucose-6-phosphate dehydrogenase deficiency (G6PDd) and sickle cell trait (SCT) and the impact on anemia outcomes among pregnant women exposed to frequent infectious diseases. Over a six-year period (March 2013 to October 2019), 8473 pregnant women attending antenatal clinics (ANCs) at major referral hospitals in Northern Ghana were recruited and diagnosed for common infectious diseases (malaria, syphilis, hepatitis B, and HIV), G6PDd, and SCT. The prevalence of all the infections and anemia did not differ between women with and without G6PDd (χ2 < 3.6, p > 0.05 for all comparisons). Regression analysis revealed a significantly higher proportion of SCT in pregnant women with G6PDd than those without G6PDd (AOR = 1.58; p < 0.011). The interaction between malaria and SCT was observed to be associated with anemia outcomes among the G6PDd women (F-statistic = 10.9, p < 0.001). Our findings show that anemia is a common condition among G6PDd women attending ANCs in northern Ghana, and its outcome is impacted by malaria and SCT. This warrants further studies to understand the impact of antimalarial treatment and the blood transfusion outcomes in G6PDd/SCT pregnant women.

Does glucose-6-phosphate dehydrogenase deficiency worsen the clinical features of sickle cell disease? A multi-hospital-based cross-sectional study

BACKGROUND

The impact of glucose-6-phosphate dehydrogenase deficiency(G-6-PD) on the clinical course of sickle cell disease(SCD) is still controversial. The objectives of this study were to determine the prevalence of G-6-PD deficiency in patients with SCD and its effect on their clinical course.

METHODS

A cross-sectional study of 122 SCD patients and 211 healthy blood donors was conducted in Kisangani city. Data were collected through clinical examination supplemented by patient medical records, and laboratory tests based on a survey form. G-6-PD activity was measured by spectrophotometry and the screening for SCD by the HemoTypeSC^® rapid test. Statistical analysis was done using SPSS ver. 20.0.

RESULTS

The prevalence of G-6-PD deficiency did not differ between SCD and non-SCD subjects, 35.2% vs. 33.6% respectively(p = .767). When comparing the hemoglobin level between SCD patients with and without G-6-PD deficiency, no significant difference was observed. However, in the 6 months prior to the study, SCD patients with G-6-PD deficiency had on average more transfusions than non-deficient SCD patients, 0.64 ± 0.897 vs. 0.24 ± 0.486(p = .004). Similarly, considering the clinical events of the last 12 months prior to the study, there were more hospitalizations, major vaso-occlusive crises and anemia requiring blood transfusion among G-6-PD deficient SCD patients compared to no-deficient, respectively 1.42 ± 1.451vs. 0.76 ± 1.112(p = .007); 1.37 ± 1.092 vs. 0.85 ± 1.014(p = .005); 0.74 ± 0.902 vs. 0.38 ± 0.739 (p = .007).

CONCLUSION

The prevalence of G-6-PD deficiency in SCD patients was high but did not differ from that observed in controls. In addition, G-6-PD deficiency appeared to worsen the clinical features of SCD. Nevertheless, prospective studies further clarifying this observation are needed.

The clinical impact of glucose-6-phosphate dehydrogenase deficiency in patients with sickle cell disease

PURPOSE OF REVIEW

Glucose-6-phosphate dehydrogenase (G6PD) deficiency and sickle cell disease (SCD) cause hemolysis, often occurring in individuals of African descent. These disorders co-occur frequently, and possibly interact, altering clinical outcomes in SCD. However, epidemiological investigations of SCD with G6PD deficiency have produced variable results. This contribution reviews the available data about the interaction of G6PD deficiency and SCD.

RECENT FINDINGS

Overall, G6PD deficiency contributes few, if any, effects to laboratory values and clinical outcomes in SCD patients, but may impact transfusion efficacy. This observation is most likely because of the relatively increased G6PD activity in the young red blood cell (RBC) population seen in SCD patients with or without G6PD deficiency. In addition, G6PD deficiency possibly interacts with other genetic modifiers, such as α thalassemia, hemoglobin F levels and SCD haplotype.

SUMMARY

Although G6PD deficiency is relatively common, it does not appear to clinically impact patients with SCD. Nonetheless, it is important to evaluate G6PD status in patients with SCD to avoid the use of medications that may cause hemolysis. Future studies evaluating the clinical impact of transfusions from G6PD-deficient RBC donors would be of the greatest benefit to the current literature.

Clinical complications of G6PD deficiency in Latin American and Caribbean populations: systematic review and implications for malaria elimination programmes

Background

Although G6PDd individuals are generally asymptomatic throughout their life, the clinical burden of this genetic condition includes a range of haematological conditions, including acute haemolytic anaemia (AHA), neonatal jaundice (NNJ) and chronic non-sphaerocytic anaemia (CNSA). In Latin America (LA), the huge knowledge gap regarding G6PDd is related to the scarce understanding of the burden of clinical manifestation underlying G6PDd carriage. The aim of this work was to study the clinical significance of G6PDd in LA and the Caribbean region through a systematic review.

Methods

A systematic search of the published literature was undertaken in August 2013. Bibliographies of manuscripts were also searched and additional references were identified. Only original research was included. All study designs were included, as long as any clinical information was present. Studies were eligible for inclusion if they reported clinical information from populations living in LA or Caribbean countries or about migrants from these countries living in countries outside this continent.

Results

The Medline search generated 487 papers, and the LILACS search identified 140 papers. After applying the inclusion criteria, 100 original papers with any clinical information on G6PDd in LA were retrieved. Additionally, 16 articles were included after reading the references from these papers. These 116 articles reported data from 18 LA and Caribbean countries. The major clinical manifestations reported from LA countries were those related to AHA, namely drug-induced haemolysis. Most of the published works regarding drug-induced haemolysis in LA referred to haemolytic crises in P. vivax malaria patients during the course of the treatment with primaquine (PQ). Favism, infection-induced haemolysis, NNJ and CNSA appear to play only a minor public health role in this continent.

Conclusion

Haemolysis in patients using PQ seems to be the major clinical manifestation of G6PDd in LA and contributes to the morbidity of P. vivax infection in this continent, although the low number of reported cases, which could be linked to under-reporting of complications. These results support the need for better strategies to diagnose and manage G6PDd in malaria field conditions. Additionally, Malaria Control Programmes in LA should not overlook this condition in their national guidelines.

Oxidative stress in sickle cell disease: an overview of erythrocyte redox metabolism and current antioxidant therapeutic strategies

Erythrocytes have an environment of continuous pro-oxidant generation due to the presence of hemoglobin (Hb), which represents an additional and quantitatively significant source of superoxide (O2(-)) generation in biological systems. To counteract oxidative stress, erythrocytes have a self-sustaining antioxidant defense system. Thus, red blood cells uniquely function to protect Hb via a selective barrier allowing gaseous and other ligand transport as well as providing antioxidant protection not only to themselves but also to other tissues and organs in the body. Sickle hemoglobin molecules suffer repeated polymerization/depolymerization generating greater amounts of reactive oxygen species, which can lead to a cyclic cascade characterized by blood cell adhesion, hemolysis, vaso-occlusion, and ischemia-reperfusion injury. In other words, sickle cell disease is intimately linked to a pathophysiologic condition of multiple sources of pro-oxidant processes with consequent chronic and systemic oxidative stress. For this reason, newer therapeutic agents that can target oxidative stress may constitute a valuable means for preventing or delaying the development of organ complications.

Impact of glucose-6-phosphate dehydrogenase deficiency on sickle cell anaemia expression in infancy and early childhood: a prospective study

In patients with sickle cell anaemia (SCA), concomitant glucose-6-phosphate dehydrogenase (G6PD) deficiency is usually described as having no effect and only occasionally as increasing severity. We analysed sequential clinical and biological data for the first 42 months of life in SCA patients diagnosed by neonatal screening, including 27 G6PD-deficient patients, who were matched on sex, age and parents' geographic origin to 81 randomly selected patients with normal G6PD activity. In the G6PD-deficient group, steady-state haemoglobin was lower (-6·2 g/l, 95% confidence interval (CI), [-10·1; -2·3]) and reticulocyte count higher (247 × 10(9) /l, 95%CI, [97; 397]). The acute anaemic event rate was 3 times higher in the G6PD-deficient group (P < 10(-3) ). A higher proportion of G6PD-deficient patients required blood transfusion (20/27 [74%] vs. 37/81 [46%], P < 10(-3) ), for acute anaemic events, and also vaso-occlusive and infectious events. No significant between-group differences were found regarding the rates of vaso-occlusive, infectious, or cerebrovascular events. G6PD deficiency in babies with SCA worsens anaemia and increases blood transfusion requirements in the first years of life. These effects decrease after 2 years of age, presumably as the decline in fetal haemoglobin levels leads to increased sickle cell haemolysis and younger red blood cells with higher G6PD activity.

Anemia in patients with coinherited thalassemia and glucose-6-phosphate dehydrogenase deficiency

Thalassemia and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency are genetic disorders that cause hemolytic anemia. In areas with high frequencies of both hematological disorders, coinheritance of G-6-PD deficiency with thalassemia can be found. Whether G-6-PD deficiency, coinherited with thalassemia, enhances severe anemia is still unclear. Hematological parameters between thalassemia carriers with G-6-PD deficiency and those without G-6-PD deficiency were compared. The G-6-PD deficiency was diagnosed in 410 blood samples from thalassemia patients using a fluorescent spot test. The levels of hemoglobin (Hb), packed cell volume (PCV), mean corpuscular volume (MCV) and Hb A2/Hb E [β26(B8)Glu→Lys; HBB: c.79G>A] were measured using an automated blood counter and high performance liquid chromatography (HPLC), respectively. The G-6-PD deficiency was found in 37 samples (9.02%). Mean levels of Hb, PCV, MCV and Hb A2/E were similar between the two groups. Thus, G-6-PD deficiency did not enhance red blood cell pathology or induce more anemic severity in thalassemia patients.

Pediatric sickle cell retinopathy: correlation with clinical factors

BACKGROUND

Sickle cell disease (SCD) occurs in 1 of every 500 African American births and 1 of every 36,000 Hispanic American births. Of children with SCD, 16.7% to 96.3% develop sickle retinopathy (SR). This study was designed to determine whether certain factors are associated with SR and whether SR is correlated with a greater incidence of other SCD manifestations.

METHODS

A retrospective analysis was performed of 258 children with SCD seen in the ophthalmology clinic at a large urban children's hospital. Of these, 54 children with SR were matched for age and sickle variant with 54 children with normal examinations. Data extracted included demographics, type of retinopathy, presence of glucose-6-phosphate dehydrogenase (G6PD) deficiency, and history of acute chest syndrome, transfusions, pulmonary hypertension, renal disease, cerebrovascular accident, aplastic crisis, splenic sequestration, priapism, osteonecrosis, gallstones, pneumonia, leg ulcers, vaso-occlusive pain crises, and death.

RESULTS

Of the children with SR, 11 (20.3%) had active proliferative disease, 32 (56.1%) had hemoglobin SS, 18 (31.6%) had hemoglobin SC, and 4 (7.0%) had hemoglobin S-beta thalassemia. Several factors were correlated with retinopathy: pain crisis (odds ratio [OR], 5.00; p=0.011), male sex (OR, 4.20, p=0.004), and splenic sequestration (OR, 4.00; p=0.013). G6PD deficiency was more common in patients with retinopathy, although this was not statistically significant (OR, 4.20; p=0.054). No other factors, including frequency of pain crisis, were statistically significant.

CONCLUSIONS

Patients with pain crisis and splenic sequestration should be considered for early ophthalmic evaluation. Those with G6PD deficiency may also deserve early screening. By identifying patients at high risk for SR, we can refine screening protocols to safeguard patients from vision loss.

Association of G6PD with lower haemoglobin concentration but not increased haemolysis in patients with sickle cell anaemia

The genetic bases of the highly variable degrees of anaemia and haemolysis in persons with Hb SS are not fully known, but several studies have indicated that G6PD deficiency is not a factor. The G6PD(202A) and G6PD(376G) alleles and alpha-thalassaemia were determined by molecular genetic testing in 261 children and adolescents with Hb SS in a multicentre study. G6PD(202A,376G) (G6PD A-) was defined as hemizygosity for both alleles in males and homozygosity in females. Among the participants 41% were receiving hydroxycarbamide. The prevalence of G6PD(202A,376G) was 13.6% in males and 3.3% in females with an overall prevalence of 8.7%. G6PD(202A,376G) was associated with a 10 g/l decrease in haemoglobin concentration (P = 0.008) but not with increased haemolysis as measured by lactate dehydrogenase, bilirubin, aspartate-aminotransferase, reticulocyte count or a haemolytic component derived from these markers (P > 0.09). Similar results were found within a sub-group of children who were not receiving hydroxycarbamide. By comparison, single and double alpha-globin deletions were associated with progressively higher haemoglobin concentrations (P = 0.005 for trend), progressively lower values for haemolytic component (P = 0.007), and increased severe pain episodes (P < 0.001). In conclusion, G6PD(202A,376G) may be associated with lower haemoglobin concentration in sickle cell anaemia by a mechanism other than increased haemolysis.

Effect of G-6 PD deficiency on sickle cell disease in Saudi Arabia

High incidence of G6PD deficiency has been reported in areas of the eastern province of Saudi Arabia where sickle cell gene is also prevalent. This study was conducted to assess the co-incidence of this enzymopathy with Hb S and its influence upon the clinical and hematological expression of sickle cell disease. Eighty three children with SS disease, 145 patients with sickle cell trait and 100 random cord blood as samples with normal Hb AF, and an FS electrophoretic pattern respectively were examined. The frequency of interaction of G6PD deficiency with Hb S was found significantly increased but no effect of this enzyme defect was discerned on the clinical and hematological status of homozygous sickle cell disease.

Comparison of homozygous sickle cell disease in northern Greece and Jamaica

The clinical and haematological features of homozygous sickle cell (SS) disease were compared in 30 Greek and 310 Jamacian patients. Deletional alpha-thalassaemia, which modifies SS disease, is rare among Greek patients, so only Jamacian patients with four alpha-globin genes were included in the control group. Greek patients had higher total haemoglobin concentration and red cell counts, and lower mean cell haemoglobin concentration (MCHC) and reticulocyte counts. They also had a more normal body build and more adults had persistent splenomegaly. Fewer had a history of leg ulceration or priapism but more reported acute chest syndrome. The comparatively mild disease in Greek patients is consistent with less haemolysis and sickling and therefore less bone marrow expansion. In the absence of amelioriating factors such as high HbF concentration or alpha-thalassaemia, these findings may be explained by the low MCHC.

Aspects of sickle cell gene in Saudi Arabia--interaction with glucose-6-phosphate dehydrogenase deficiency

Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency and sickle cell haemoglobin (Hb S) are red cell genetic abnormalities that occur at a high frequency in several areas of the world including several areas of Saudi Arabia. Genetic and clinical interactions between these two disorders are reported to occur in some populations. In the present investigations, samples from affected individuals were studied for the prevalence of G-6-PD deficiency and Hb S genes. The results of haematological parameters and common clinical findings in the Hb S homozygotes with and without G-6-PD deficiency are presented and the possibility that the two conditions interact beneficially is discussed.