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

Adrenal Insufficiency in Patients with Beta Thalassemia: A Meta-Analysis

Background and Objectives: Adrenal insufficiency (AI) can be a significant concern in patients with transfusion-dependent homozygous beta thalassemia (bThal) due to the chronic disease burden and frequent blood transfusions that these patients require. The prevalence of AI in this population remains unclear, with studies often lacking control groups for comparison. This meta-analysis aimed to estimate the proportion of patients with transfusion-dependent bThal who exhibit evidence of AI. Materials and Methods: A systematic review following PRISMA guidelines identified 19 studies for analysis. Results: Despite the variability in the diagnostic methods used to ascertain AI, the meta-analysis revealed that approximately one-third of patients had evidence of AI, with the prevalence rising to 50% in studies focused on adults with bThal. Conclusions: These findings suggest an increased risk of AI in patients with bThal compared to the general population. Clinicians should consider tailored management strategies, including glucocorticoid coverage during surgical procedures, to mitigate the risk of adrenal crises in this vulnerable patient group. Further research is needed to optimize adrenal surveillance and management in patients with bThal.

New Entity-Thalassemic Endocrine Disease: Major Beta-Thalassemia and Endocrine Involvement

Beta-thalassemia (BTH), a recessively inherited haemoglobin (Hb) disorder, causes iron overload (IO), extra-medullary haematopoiesis and bone marrow expansion with major clinical impact. The main objective of this review is to address endocrine components (including aspects of reproductive health as fertility potential and pregnancy outcome) in major beta-thalassemia patients, a complex panel known as thalassemic endocrine disease (TED). We included English, full-text articles based on PubMed research (January 2017-June 2022). TED includes hypogonadism (hypoGn), anomalies of GH/IGF1 axes with growth retardation, hypothyroidism (hypoT), hypoparathyroidism (hypoPT), glucose profile anomalies, adrenal insufficiency, reduced bone mineral density (BMD), and deterioration of microarchitecture with increased fracture risk (FR). The prevalence of each ED varies with population, criteria of definition, etc. At least one out of every three to four children below the age of 12 y have one ED. ED correlates with ferritin and poor compliance to therapy, but not all studies agree. Up to 86% of the adult population is affected by an ED. Age is a positive linear predictor for ED. Low IGF1 is found in 95% of the population with GH deficiency (GHD), but also in 93.6% of persons without GHD. HypoT is mostly pituitary-related; it is not clinically manifested in the majority of cases, hence the importance of TSH/FT4 screening. HypoT is found at any age, with the prevalence varying between 8.3% and 30%. Non-compliance to chelation increases the risk of hypoT, yet not all studies confirmed the correlation with chelation history (reversible hypoT under chelation is reported). The pitfalls of TSH interpretation due to hypophyseal IO should be taken into consideration. HypoPT prevalence varies from 6.66% (below the age of 12) to a maximum of 40% (depending on the study). Serum ferritin might act as a stimulator of FGF23. Associated hypocalcaemia transitions from asymptomatic to severe manifestations. HypoPT is mostly found in association with growth retardation and hypoGn. TED-associated adrenal dysfunction is typically mild; an index of suspicion should be considered due to potential life-threatening complications. Periodic check-up by ACTH stimulation test is advised. Adrenal insufficiency/hypocortisolism status is the rarest ED (but some reported a prevalence of up to one third of patients). Significantly, many studies did not routinely perform a dynamic test. Atypical EM sites might be found in adrenals, mimicking an incidentaloma. Between 7.5-10% of children with major BTH have DM; screening starts by the age of 10, and ferritin correlated with glycaemia. Larger studies found DM in up to 34%of cases. Many studies do not take into consideration IGF, IGT, or do not routinely include OGTT. Glucose anomalies are time dependent. Emerging new markers represent promising alternatives, such as insulin secretion-sensitivity index-2. The pitfalls of glucose profile interpretation include the levels of HbA1c and the particular risk of gestational DM. Thalassemia bone disease (TBD) is related to hypoGn-related osteoporosis, renal function anomalies, DM, GHD, malnutrition, chronic hypoxia-induced calcium malabsorption, and transplant-associated protocols. Low BMD was identified in both paediatric and adult population; the prevalence of osteoporosis/TBD in major BTH patients varies; the highest rate is 40-72% depending on age, studied parameters, DXA evaluation and corrections, and screening thoracic-lumbar spine X-ray. Lower TBS and abnormal dynamics of bone turnover markers are reported. The largest cohorts on transfusion-dependent BTH identified the prevalence of hypoGn to be between 44.5% and 82%. Ferritin positively correlates with pubertal delay, and negatively with pituitary volume. Some authors appreciate hypoGn as the most frequent ED below the age of 15. Long-term untreated hypoGn induces a high cardiovascular risk and increased FR. Hormonal replacement therapy is necessary in addition to specific BTH therapy. Infertility underlines TED-related hormonal elements (primary and secondary hypoGn) and IO-induced gonadal toxicity. Males with BTH are at risk of infertility due to germ cell loss. IO induces an excessive amount of free radicals which impair the quality of sperm, iron being a local catalyser of ROS. Adequate chelation might improve fertility issues. Due to the advances in current therapies, the reproductive health of females with major BTH is improving; a low level of statistical significance reflects the pregnancy status in major BTH (limited data on spontaneous pregnancies and growing evidence of the induction of ovulation/assisted reproductive techniques). Pregnancy outcome also depends on TED approach, including factors such as DM control, adequate replacement of hypoT and hypoPT, and vitamin D supplementation for bone health. Asymptomatic TED elements such as subclinical hypothyroidism or IFG/IGT might become overt during pregnancy. Endocrine glands are particularly sensitive to iron deposits, hence TED includes a complicated puzzle of EDs which massively impacts on the overall picture, including the quality of life in major BTH. The BTH prognostic has registered progress in the last decades due to modern therapy, but the medical and social burden remains elevated. Genetic counselling represents a major step in approaching TH individuals, including as part of the pre-conception assessment. A multidisciplinary surveillance team is mandatory.

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)