Hormonal and echocardiographic abnormalities in adult patients with sickle-cell anemia in Bahrain

TSH Receptor Reduces Hemoglobin S Polymerization and Increases Deformability and Adhesion of Sickle Erythrocytes

SCD is a hereditary disorder caused by genetic mutation in the beta-globin gene, resulting in abnormal hemoglobin, HbS that forms sickle-shaped erythrocytes under hypoxia. Patients with SCD have endocrine disorders and it was described that 7% of these patients have clinical hypothyroidism. Recent studies have shown that mature erythrocytes possess TSH receptors. Thus, we aimed to assess the effects of TSH on SCD erythrocytes. The experiments were conducted using different concentrations of TSH (1, 2, 3, and 5 mIU/L). In HbS polymerization assay, erythrocytes were exposed to TSH in hypoxia to induce polymerization, and measurements were taken for 30 minutes. The deformability assay was made using Sephacryl-S 500 columns to separate deformable from nondeformable cells. Static adhesion test utilized thrombospondin to assess erythrocyte adhesion in the presence of TSH. TSH at all contractions were able to reduce polymerization of HbS and increase deformability. The static adhesion of erythrocytes at the lowest concentrations of 1 and 2 mIU/L were increased, but at higher contractions of 3 and 5 mIU/L, static adhesion was not modulated. The results suggest that TSH has potential involvement in the pathophysiology of sickle cell disease by inhibiting HbS polymerization, positively modulating deformability and impacting static adhesion to thrombospondin.

Endocrinopathies in Hemoglobinopathies: What Is the Role of Iron?

Hemoglobinopathies, including β-thalassemia and sickle cell disease (SCD), are common genetic blood disorders. Endocrine disorders are frequent manifestations of organ damage observed mainly in patients with β-thalassemia and rarely in SCD. Iron overload, oxidative stress-induced cellular damage, chronic anemia, and HCV infection contribute to the development of endocrinopathies in β-thalassemia. The above factors, combined with vaso-occlusive events and microcirculation defects, are crucial for endocrine dysfunction in SCD patients. These endocrinopathies include diabetes mellitus, hypothyroidism, parathyroid dysfunction, gonadal and growth failure, osteoporosis, and adrenal insufficiency, affecting the quality of life of these patients. Thus, we aim to provide current knowledge and data about the epidemiology, pathogenesis, diagnosis, and management of endocrine disorders in β-thalassemia and SCD. We conducted a comprehensive review of the literature and examined the available data, mostly using the PubMed and Medline search engines for original articles. In the era of precision medicine, more studies investigating the potential role of genetic modifiers in the development of endocrinopathies in hemoglobinopathies are essential.

Prevalence and factors associated with hypothyroidism in children with sickle cell anemia aged 6 months - 17 years attending the Sickle Cell Clinic, Mulago Hospital, Uganda; a cross-sectional study

PURPOSE

Hypothyroidism has been reported at a prevalence of 6% in children and adolescents with Sickle cell anemia. In this study, we determined the prevalence and factors associated with hypothyroidism among children with Sickle cell anemia attending the Sickle Cell Clinic, in Mulago hospital, Uganda.

METHODS

A cross-sectional study was conducted among children aged 6 months - 17 years with a confirmed diagnosis of Sickle Cell Anemia, with no prior diagnosis of hypothyroidism and in steady state attending the Sickle Cell Clinic in Mulago hospital. Data was collected using a structured questionnaire and a blood sample was used to measure thyroid stimulating hormone and free thyroxine.

RESULTS

Of the 332 children enrolled, sixty (18.1%) participants had sub-clinical hypothyroidism (95% CI: 14.3 - 22.6). Factors associated with hypothyroidism included constipation [adjusted odds ratio: 3.1, 95% CI:1.0 - 9.0, p = 0.043] and male sex [adjusted odds ratio:2.0, 95% CI:1.1- 3.5, p = 0.025].

CONCLUSION

Approximately 1 in 5 children (18.1%) had sub-clinical hypothyroidism. Males and children who presented with constipation were more likely to have sub-clinical hypothyroidism.

Sickle cell disease in Gulf Cooperation Council countries: a systematic review

INTRODUCTION

Evidence related to the national burden of Sickle Cell Disease (SCD) in Gulf Cooperation Council (GCC) largely fragmented. Thus, the aim of this study is to systemically review studies from GCC countries to assess the epidemiological profile of SCD.

AREAS COVERED

We searched combinations of key terms in MEDLINE/PubMed, CINAHL, and EMBASE. We selected relevant observational studies reporting the frequency, incidence, prevalence, risk factors, mortality rate, and complications of SCD among the GCC population. Studies restricted to laboratory diagnostic tests, experimental and animal studies, review articles, case reports and series, and conference proceedings and editorials were excluded. A total of 1,347 articles were retrieved, out of which 98 articles were found to be eligible and included in the study. The total number of participants from all the included studies was 3496447. The prevalence of SCD ranged from 0.24%-5.8% across the GCC and from 1.02%-45.8% for the sickle cell trait. Consanguineous marriage was a risk factor for likely giving children affected with hemoglobinopathies.

EXPERT OPINION

The prevalence of SCD and its complications vary among GCC. Because of the high prevalence of SCD and its complications, health authorities should focus on more rigorous prevention and treatment strategies.

Ultrasonographic shear wave elastography of the thyroid in patients with sickle cell anemia

Background

Although thyroid radiology has been conducted in patients with sickle cell anemia (SCA), to our knowledge, there is no report of thyroid gland assessment using ultrasonographic shear wave elastography (US-SWE).

Objectives

To determine values for ultrasonographic US-SWE of the thyroid in patients with SCA and correlations between thyroid elasticity and biochemical variables used to evaluate thyroid function.

Methods

Prospective case-control observational study of 36 patients with SCA and 33 healthy volunteer controls. US-SWE measurements of thyroid gland parenchyma and biochemical parameters of the participants were obtained and compared, and the diagnostic accuracy of elasticity was determined.

Results

The thyroid volume was smaller in patients with SCA than that in controls (P = 0.001). Compared with the controls, the patients with SCA had significantly lower serum levels of free triiodothyronine (fT3) (P = 0.004) and thyroglobulin (Tg) (P = 0.001) and significantly higher levels of thyroid-stimulating hormone (P = 0.028). Thyroid stiffness was significantly higher in the left lobe (LL) of the patients with SCA than in the controls (P = 0.003). In the patients with SCA, we found a significant correlation between right lobe (RL) and LL stiffness and serum levels of Tg (RL [r = -0.439] and LL [r = -0.484]; P = 0.021) and fT3 (RL [r = -0.463] and LL [r = -0.386]; P = 0.012). Receiver operating characteristic (ROC) curve analysis of thyroid elasticity that represented a diagnosis of SCA found a cutoff of >7.31 kPa, a sensitivity of 52.0%, and a specificity of 72.0% for the RL (P = 0.316, area under the curve [AUC] 0.570), and a cutoff of >8.06 kPa, a sensitivity of 58.0%, and a specificity of 84.0% for the LL (P = 0.011, AUC 0.680).

Conclusions

US-SWE can be used to follow up thyroid changes in patients with SCA.

Lower hair cortisol among patients with sickle cell disease may indicate decreased adrenal reserves

INTRODUCTION

Sickle cell disease (SCD) is a chronic illness that presents with a wide range of phenotypic variation. Stress may be a contributing factor to differences that are found in this population.

OBJECTIVES

Our objective is to determine the relationship between hair cortisol content (HCC), a biomarker of stress, and other clinical measures in individuals with SCD.

METHODS

We collected hair samples and other clinical measures from 73 subjects with SCD (mean age: 39 ± 12 years, 63% female).

RESULTS

HCC was lower among individuals who had greater than 30% hemoglobin S, compared with those who had less than 30% hemoglobin S (W=272.5, P=0.01). Lower HCC was also associated with report of not being on a chronic transfusion program (β=48.34, SE=14.09, P=0.001) and higher ferritin levels (β=-0.006, SE=0.002, P=0.02). Furthermore, HCC was significantly correlated with serum cortisol (r_s=0.26, P=0.03) and corticosterone (r_s=0.29, P=0.01). We also observed a consistent pattern of low steroid values among our population.

CONCLUSION

Our findings suggest that individuals with higher hemoglobin S and ferritin, both markers of severe SCD, may have decreased cortisol levels. This is consistent with the relationship we observed between higher HCC among individuals who are on a chronic blood transfusion program, which typically increases quality of life. Our results suggest that hair cortisol may be an indicator in patients with SCD who could be at risk for developing adrenal insufficiency. We recommend that clinicians treating patients with SCD follow the Endocrine Society guidelines for testing for adrenal insufficiency and treat accordingly.

The Effect of Serum Ferritin Level on Gonadal, Prolactin, Thyroid Hormones, and Thyroid Stimulating Hormone in Adult Males with Sickle Cell Anemia

Background

Sickle cell anaemia (SCA) is an inherited hemoglobinopathy resulting in sickling of erythrocytes that cause micro-vascular obstruction leading to acute complications and chronic organ damage. Adults with SCA have endocrine complications and metabolic alterations. The aim of this study was to assess the association between gonadal and thyroid hormones with iron indices and to explore the potential association between serum ferritin levels and sex hormones in adult males with sickle cell disease in New Prince Saud Bin Jalawy Hospital (NPSBJH) in Hofuf city (Eastern region of Saudi Arabia) where there are many patients with SCA.

Methods

A cross-sectional analytical study was carried out in the Haematology Clinic at NPSBJH in 2018. A total of eighty (80) male patients with sickle cell anaemia were included in this study and were divided into two groups according to serum ferritin level. Group I (G-I): Included 40 male patients with high serum ferritin level and group II (G-II): included 40 male patients with normal serum ferritin level.

Results

There was a significant difference in height/cm between GI and Gil, P value= 0.006. Serum ferritin was significantly higher in GI (P value= 0.000), and serum TIBC was significantly higher in G-II. (P value= 0.022). Testosterone level was significantly higher in G-II (P value= 0.018). Luteinizing hormone (LH) was significantly higher in group I (P-value 0.019). There was a significant relation between serum ferritin level in G-I and the following: serum iron, TIBC, serum testosterone, LH, prolactin, free T3 and free T4.

Conclusion

Adult males with SCD with high serum ferritin level were shorter than adult males with SCD who had normal serum ferritin level and had a significant lower level of serum testosterone and significant high level of LH and this was most likely due to endocrine dysfunction secondary to high ferritin level and iron overload.

Thyroid hemodynamic alterations in Egyptian patients with sickle cell disease: relation to disease severity, total body iron and thyroid function

Background: Intraparenchymal thyroid Doppler measurements might be considered a useful index of the thyroid status as well as micro-circulation elsewhere in the body among sickle cell disease (SCD) patients. The authors aim to evaluate the intra-thyroidal hemodynamic changes and thyroidal volume in SCD patients and its relation to the disease severity, and thyroid functions tests as well as iron overload state. Methods: Sixty SCD patients, randomly recruited from the regular attendants of the Pediatric Hematology Clinic, Ain Shams University, Cairo, Egypt, were studied focusing on the disease duration, the transfusion history, the recorded Hydroxyurea, and chelation therapies and the vaso-occlusive crises history. Thyroid Doppler ultrasonography [Thyroid volume, Resistance index (RI) and pulsatility index (PI)] was performed and liver & cardiac MRI were assessed. Results: Thirteen (21.7%) of the SCD patients had hypothyroidism by thyroid function tests. SCD patients had significantly higher RI and PI values and a lower thyroid volume compared to the control group. No significant correlations were found between the thyroid functions tests and the thyroid Doppler parameters; a negative correlation of the disease duration to the thyroid volume and a positive one to RI & PI values were found. The mean serum ferritin did not significantly correlate to the thyroid Doppler indices nor did Liver and cardiac MRI results. Conclusion: The authors demonstrated an increased intra-thyroidal RI & PI and a decreased thyroid volume among SCD patients which might be related to impaired thyroidal microcirculation and vasculopathy rather than iron overload.

Depletion of Intestinal Microbiome Partially Rescues Bone Loss in Sickle Cell Disease Male Mice

Osteoporosis or osteopenia are common clinical manifestations of sickle cell disease (SCD) with unclear mechanisms. Since senescence of circulating neutrophil can be modulated by signals derived from intestinal microbiome and neutrophils are abundant in bone marrow and can regulate osteoblasts and osteoclasts, we examined whether gut microbiome contributes to bone loss in SCD mice. SCD and their littermates control mice were treated with antibiotics to deplete gut microbiome. At the end of 7 weeks treatment, serum was collected for biochemistry marker measurements. Bone mass and remodeling were evaluated by dual beam X-ray absorptiometry, micro-computed tomography, and histomorphometry. Bone-related genes in tibia and barrier marker genes in the small intestine were analyzed by quantitative PCR. Antibiotic treatment rescued increased intestinal inflammatory cytokine marker genes (Tnfα, IL17, Ifnγ) expression, rescued decreased intestinal barrier marker genes (claudin 3 and claudin 15) expression, and rescued increased serum cytokines (IFNγ, IL27, IL10) in SCD mice. Antibiotic significantly improved decreased bone mass in SCD mice mainly through enhanced osteoblast function and increased osteoblast-related genes (Runx2 and Igf1) expression in SCD mice. Our findings support that increased bacteria load augments antigenic load traversing the impaired intestinal barrier through inflammation, leading to increased inflammatory cytokines, impaired osteoblast function, and bone loss in SCD mice.