Evaluation of the glucocorticoid, mineralocorticoid, and adrenal androgen secretion dynamics in a large cohort of patients aged 6-18 years with transfusion-dependent β-thalassemia major, with an emphasis on the impact of cardiac iron load

Association and mediation analyses among multiple metal exposure, mineralocorticoid levels, and serum ion balance in residents of northwest China

Toxic metals are vital risk factors affecting serum ion balance; however, the effect of their co-exposure on serum ions and the underlying mechanism remain unclear. We assessed the correlations of single metal and mixed metals with serum ion levels, and the mediating effects of mineralocorticoids by investigating toxic metal concentrations in the blood, as well as the levels of representative mineralocorticoids, such as deoxycorticosterone (DOC), and serum ions in 471 participants from the Dongdagou-Xinglong cohort. In the single-exposure model, sodium and chloride levels were positively correlated with arsenic, selenium, cadmium, and lead levels and negatively correlated with zinc levels, whereas potassium and iron levels and the anion gap were positively correlated with zinc levels and negatively correlated with selenium, cadmium and lead levels (all P < 0.05). Similar results were obtained in the mixed exposure models considering all metals, and the major contributions of cadmium, lead, arsenic, and selenium were highlighted. Significant dose-response relationships were detected between levels of serum DOC and toxic metals and serum ions. Mediation analysis showed that serum DOC partially mediated the relationship of metals (especially mixed metals) with serum iron and anion gap by 8.3% and 8.6%, respectively. These findings suggest that single and mixed metal exposure interferes with the homeostasis of serum mineralocorticoids, which is also related to altered serum ion levels. Furthermore, serum DOC may remarkably affect toxic metal-related serum ion disturbances, providing clues for further study of health risks associated with these toxic metals.

Spectrum of Adrenal Dysfunction in Hemoglobin E/Beta Thalassemia

BACKGROUND

Adrenal insufficiency (AI) in hemoglobin E (HbE)/beta thalassemia, including evaluation of mineralocorticoid axis, had not been studied.

AIMS AND OBJECTIVES

In this study, we attempted to evaluate the prevalence of AI in HbE/beta thalassemia and wanted to determine if the prevalence of AI varied according to severity of HbE/beta thalassemia and transfusion requirements.

METHODS

In this observational, cross-sectional study, 104 patients with HbE/beta thalassemia were evaluated. Among them, 57 and 47 were transfusion dependent and non-transfusion dependent. According to Mahidol criteria, patients were classified into mild (n = 39), moderate (n = 39), and severe (n = 26) disease. Early morning (8 Am) serum cortisol, plasma ACTH, and plasma aldosterone, renin were measured. Patients with baseline cortisol of 5 to 18 μg/dL underwent both 1 μg and 250 μg short Synacthen test. According to these results, patients were classified as having either normal, subclinical, or overt (primary/secondary) adrenal dysfunction.

RESULTS

Adrenal insufficiency was found in 41% (n = 43). Among them 83.7% (n = 34) had primary AI and 16.3% (n = 9) had secondary AI. Thirty-three patients (31%) with normal or elevated ACTH and with low or normal aldosterone with high renin were diagnosed as having subclinical AI. There was no difference in prevalence of AI between transfusion dependent and non-transfusion dependent (P = .56) nor was there was any difference in prevalence of AI according to disease severity (P = .52).

CONCLUSION

Adrenal insufficiency is common in HbE/beta thalassemia and is independent of transfusion dependency and disease severity.

Establishment of a thalassaemia major quality improvement collaborative in Pakistan

OBJECTIVES

The aim of this study was to establish multidisciplinary care for patients with transfusion-dependent thalassaemia (TDT) by creating a TDT quality improvement (QI) collaborative in a resource-constrained setting. This study presents our initial experience of creating this collaborative, the baseline characteristics of the participants, the proposed QI interventions and the outcome metrics of the collaborative.

DESIGN AND SETTING

TDT QI collaborative is a database comprising patients with TDT from four centres in Karachi, Pakistan. Study variables included symptoms of cardiac or endocrine dysfunction, physical examination including anthropometry and Tanner staging, chelation therapy, results of echocardiography, T2* cardiac MRI (CMR) and serum ferritin. The main outcome of this collaborative was improvement in TDT-related morbidity and mortality. Interventions addressing the key drivers of outcome were designed and implemented.

RESULTS

At the time of reporting, the total number of patients in this database was 295. Most patients reported cardiac symptoms corresponding to New York Heart Association class 2. Approximately half (52%, n=153) of the patients demonstrated severe myocardial iron overload (T2* <10 ms). Majority of the patients (58%, n=175) were not on adequate chelation therapy. There was no difference in echocardiographic measures of systolic and diastolic left ventricle among the different spectrums of iron overloaded myocardium.

CONCLUSION

Using T2* CMR and endocrine testing, we have identified significant burden of iron siderosis in our patients with TDT. Lack of adequate iron load assessment and standardised management was observed. Interventions designed to target these key drivers of outcome are the unique part of this QI-based TDT registry.

New Insights and Methods in the Approach to Thalassemia Major: The Lesson From the Case of Adrenal Insufficiency

Background: Thalassemia Major (TM) is a complex pathology that needs a highly skilled approach. Endocrine comorbidities are nowadays the most important complications, including hypogonadism, hypothyroidism, diabetes mellitus, and bone diseases. Recent works stated that there could be a relevant prevalence of adrenal insufficiency (AI) present in TM, and this fact may become crucial, especially in case of major stressful events.

Aim: Test the reliability of the standard test to diagnose AI in a group of TM and correlate it with clinical, hematological, and radiological data.

Methods: We evaluated endocrine damages and the efficacy of iron chelation therapy in 102 patients affected by TM. AI was assessed by tetracosactide (Synacthen) 1 mcg iv (low-dose test, LDT) stimulation test. Patients with a subnormal response (peak cortisol < 500 nmol/L) were followed up to 5 years to check the symptoms and signs of AI.

Results: We found AI in 13.7% of the population studied. We did not find any correlation between AI and all data evaluated. Only female gender seems to be a protective factor. A follow up of the patients affected by AI showed no signs of adrenal crisis, in spite of no replacement therapy.

Conclusions: Our study shows a relevant prevalence of AI in TM, especially in males. The absence of an adrenal crisis, in spite of no replacement therapy, during the long-term follow up, seems to underline that current methods to evaluate AI, in TM, should consider a different and specific diagnostic test or different cut off for diagnosis.

An ICET-A survey on occult and emerging endocrine complications in patients with β-thalassemia major: Conclusions and recommendations

In adult thalassemia major (TM) patients, a number of occult and emerging endocrine complications, such as: central hypothyroidism (CH), thyroid cancer, latent hypocortisolism, and growth hormone deficiency (GHD) have emerged and been reported. As the early detection of these complications is essential for appropriate treatment and follow-up, the International Network of Clinicians for Endocrinopathies in Thalassemia and Adolescent Medicine (ICET-A) promoted a survey on these complications in adult TM patients, among physicians (pediatricians, hematologists and endocrinologists) caring for TM patients in different countries. The data reported by 15 countries are presented. The commonest endocrine complications registered in 3.114 TM adults are CH and GHD (4.6 % and 3.0 %, respectively), followed by latent hypocortisolism (1.2%). In 13 patients (0.41%) a cytological papillary or follicular thyroid carcinoma was diagnosed in 11 and 2 patients, respectively, and a lobectomy or thyroidectomy was carried out. Of 202 TM patients below the age of 18 years, the reported endocrine complications were: GHD in 4.5%, latent hypocortisolism in 4.4% and central hypothyrodisim in 0.5%. Transition phase was an area of interest for many clinicians, especially as patients with complex chronic health conditions are responding to new treatments extending their lifespan beyond imagination.. In conclusion, our survey provides a better understanding of physicians’ current clinical practices and beliefs in the detection, prevention and treatment of some endocrine complications prevailing in adult TM patients. Regular surveillance, early diagnosis, treatment and follow-up in a multi-disciplinary specialized setting are recommended. (www.actabiomedica.it)

Clinical utility of endocrine markers predicting myocardial siderosis in transfusion dependent thalassemia major

BACKGROUND

Endocrinopathy due to iron overload is the most common morbidity whereas myocardial siderosis causing toxic cardiomyopathy is the leading cause of mortality among patients with transfusion dependent thalassemia major (TDTM). If detected early, this can be treated with aggressive chelation. T2* cardiac magnetic resonance imaging (CMR) guided chelation protocols are now the gold standard but have limited availability in low and middle-income countries. We hypothesized that markers of endocrine dysfunction would correlate with T2* CMR and can be used to predict the severity of myocardial siderosis and guide chelation therapy.

METHODOLOGY

We undertook a multicenter retrospective study of 280 patients with TDTM to assess the prevalence of endocrinopathies and the predictive value of a number of individual and composite markers of endocrinopathy with T2* CMR.

RESULTS

The prevalence of hypogonadism, stunting, hypoparathyroidism, and hypothyroidism was 82%, 69%, 40%, and 30%, respectively. The sensitivity of hypogonadism and stunting predicting severe myocardial siderosis was 90% and 80%, respectively.

CONCLUSION

We conclude that clinical markers of endocrine dysfunction, especially hypogonadism (positive likelihood ratio [LR+] = 1.4, 95% confidence interval [CI] = 1.0-1.9; positive predictive value [PPV] = 77%, 95% CI = 70-82; negative predictive value [NPV] = 57%, 95% CI = 34-77] and stunting (LR+ = 1.3, 95% CI = 1.1-1.6; PPV = 64%, 95% CI = 60-69; NPV = 55%, 95% CI = 45-64) in TDTM can predict severe myocardial siderosis and can potentially guide chelation therapy, especially where access to T2* CMR is limited.

Low-dose Synachten test with measurement of salivary cortisol in adult patients with β-thalassemia major

PURPOSE

Beta-thalassemia major is a severe, congenital hematological disorder and, if untreated, leads to early mortality. Progress in therapeutical strategies improved clinical outcomes and life expectancy; however, increased survival led to the development of new disorders, including endocrinopathies. Little is known on the possible impairment of adrenocortical function, a potentially life-threatening condition, in long-term thalassaemic survivors. We therefore decided to assess adrenal reserve and the value of salivary cortisol during ACTH stimulation in the diagnosis of adrenocortical insufficiency in adult patients with β-thalassemia major.

METHODS

Cross-sectional study including 72 adults with β-thalassemia major. Patients were tested with 1 µg ACTH for serum and salivary cortisol.

RESULTS

Subnormal serum cortisol responses to ACTH stimulation (i.e., <500 nmol/l) were registered in 15 out of 72 patients. Salivary cortisol increased in parallel with serum cortisol and a clear-cut positive correlation was detected at each timepoint. Moreover, peak salivary cortisol values after ACTH stimulation were significantly lower in patients with impaired adrenal reserve (513.6 ± 52.33 vs. 914.1 ± 44.04 nmol/l p < 0.0001).

CONCLUSIONS

Our results attest to the need for testing for adrenal insufficiency among adult thalassaemic patients, as up to 20% presented impaired adrenal reserve. Salivary and serum cortisol levels during stimulation with ACTH were closely correlated and the use of salivary cortisol sampling during ACTH testing may represent a surrogate to serum cortisol in these patients.