Endocrine gland abnormalities in thalassemia major: a brief review

GH/IGF-1 axis in a large cohort of ß-thalassemia major adult patients: a cross-sectional study

PURPOSE

GH deficit (GHD) could represent an endocrine issue in ß-Thalassemia Major (ßTM) patients. GH/IGF-1 axis has not been extensively explored in ßTM adults, so far. We aim to assess GHD and IGF-1 deficiency prevalence in ßTM adult population, focusing on the relationship with liver disease.

METHODS

Cross-sectional multi-centre study conducted on 81 adult ßTM patients (44 males, mean age 41 ± 8 years) on transfusion and chelation therapy. GHD was investigated by GHRH + arginine test. IGF-1 levels, routine biochemical exams, Fibroscan, Hepatic Magnetic Resonance Imaging (MRI) and pituitary MRI were collected.

RESULTS

Eighteen patients were affected by GHD and 63 were not (nGHD) according to GHRH + arginine test, while basal GH levels did not differ. GHD was associated with a higher BMI and a worse lipid profile (p < 0.05). No significant differences were observed regarding liver function between the two groups. Pituitary MRI scan was normal except for one case of empty sella. The 94.4% and 93.6% of GHD and nGHD, respectively, presented lower IGF-1 levels than the reference range, and mean IGF-1 SDS was significantly lower in GHD patients.

CONCLUSION

GHD is frequent in adult ßTM patients and is associated with higher BMI and worse lipid profile. nGHD patients present lower IGF-1 levels as well. There was no relationship between IGF-1 levels and liver disease. Further, multicentric studies with larger cohorts and standardized diagnostic protocols are needed.

The effect of deferasirox on endocrine complications in children with thalassemia

Endocrine system dysfunctions are the significant complications of excessive iron overload in beta thalassemia patients. The aim of this study was to evaluate the long-term effect of chelation with deferasirox on endocrine complications. The study group consisted of children with beta thalassemia who had been evaluated for the growth and pubertal development, bone metabolism, thyroid/parathyroid functions, glucose metabolism dysfunctions in the department of pediatric hematology of Ankara Dışkapı Child Health and Diseases Hematology Oncology Training And Research Hospital between 2009-2011 and reevaluated after deferasirox chelation therapy in 2018. Thirty-one transfusion dependent beta-thalassemia patients were enrolled for the study. Seventeen (54.8%) patients were male and the mean age was 16.9 ± 3.8 (9-23) years. Splenectomy was performed in 11 patients (35.5%). In the initial evaluation, 26 patients (84%) received deferoxamine and/or deferiprone and five (17%) patients received deferasirox as a chelator; in the final evaluation all patients were receiving deferasirox. The mean duration of deferasirox treatment was 5.9 ± 2.02 years (1-10 years). Of the 26 patients who had endocrine complications between 2009-2011, 18 were recovered. In the final evaluation, eight patients (25%) developed new endocrinopathies. The frequency of endocrine complications seen before the deferasirox treatment (83%) was higher than the frequency of complications while receiving deferasirox treatment (25.8%) (p < 0,05). In this study, it was determined that both existing endocrine abnormalities were reduced and recent developed problems were less likely with long-term deferasirox treatment in thalassemia patients.

Evaluation of endocrine complications in beta-thalassemia intermedia (β-TI): a cross-sectional multicenter study

BACKGROUND

Data on the prevalence and type of endocrine disorders in β-thalassemia intermedia (β-TI) patients are scarce. This multicenter study was designed to determine the prevalence of endocrine complications and the associated risk factors in a large group of β-TI patients.

METHODS

In this cross-sectional multicenter study, 726 β-TI patients, aged 2.5-80 years, registered at 12 thalassemic centers, from nine countries, were enrolled during 2017. In a subgroup of 522 patients (mean age 30.8 ± 12.1; range: 2.5-80 years) from Qatar, Iran, Oman, Cyprus, and Jordan detailed data were available.

RESULTS

Overall, the most prevalent complications were osteopenia/osteoporosis (22.3%), hypogonadism (10.1%), and primary hypothyroidism (5.3%). In the subgroup multivariate analysis, older age was a risk factor for osteoporosis (Odds ratio: 7.870, 95% CI: 4.729-13.099, P < 0.001), hypogonadism (Odds ratio: 6.310, 95% CI: 2.944-13.521, P < 0.001), and non-insulin-dependent diabetes mellitus (NIDDM; Odds ratio: 17.67, 95% CI: 2.217-140.968, P = 0.007). Splenectomy was a risk factor for osteoporosis (Odds ratio: 1.736, 95% CI: 1.012-2.977, P = 0.045). Hydroxyurea was identified as a "protective factor" for NIDDM (Odds ratio: 0.259, 95% CI: 0.074-0.902, P = 0.034).

CONCLUSIONS

To the best of our knowledge, this is the largest cohort of β-TI patients with endocrine disorders evaluated in extremely heterogenic thalassemic populations for age, clinical, hematological, and molecular composition. The study demonstrates that endocrine complications are less common in patients with β-TI compared with β-TM patients. However, regular monitoring with timely diagnosis and proper management is crucial to prevent endocrine complications in β-TI patients.

Early development of decreased β-cell insulin secretion in children and adolescents with hemoglobin H disease and its relationship with levels of anemia

BACKGROUND

Diabetes mellitus (DM) associated with iron overload has been reported among adults with transfusion-dependent thalassemia and those with non-transfusion-dependent thalassemia (NTDT), especially in β-thalassemia disease. However, little is known about glucose metabolism and how early its dysregulation can develop in α-thalassemia hemoglobin H (Hb H) disease, which is one of the most common types of NTDT worldwide.

PROCEDURE

We prospectively calculated glucose metabolism index in 40 patients (aged 10-25 years) with Hb H disease. Glucose metabolism data were compared between patients with deletional versus nondeletional Hb H, and between patients with normal versus abnormal insulin secretion/sensitivity.

RESULTS

Despite normal glucose tolerance in all patients, 52.5% had abnormal insulinogenic index indicating decreased β-cell insulin secretion. Patients with functional hemoglobin < 8 g/dL had significantly higher percentages of abnormal insulinogenic index. There was no significant difference in abnormal insulinogenic index between deletional and nondeletional Hb H.

CONCLUSION

Decreased β-cell insulin secretion is highly prevalent among children and adolescents with Hb H disease, and it is associated with levels of functional anemia at baseline, but not with the type of Hb H disease. This result warrants heightened awareness among hematologists due to potentially increased risk of DM later in life.

Endocrinopathies complicating transfusion-dependent hemoglobinopathy

OBJECTIVES

To investigate the prevalence and significance of different endocrinopathies in children and adolescents with transfusion-dependent thalassemia and sickle-cell anemia.

METHODS

This is a descriptive, retrospective study between January 2010 and July 2018 in King Abdulaziz University Hospital, Jeddah, Saudi Arabia. Data was collected through reviewing electronic hospital medical records then filling out data collection sheets and was interpreted through the IBM SPSS Statistics for Windows version 20.0 (IBM Corp, Armonk, NY, USA). Results: The total sample size was 119 patients, gender equality was almost achieved with 55.5% being male and 45.5% being female. The most common endocrinopathies were identified in the following order of short stature (39.5%), diabetes mellitus (29.4%), hypogonadism (12.6%), osteopenia (12.6%), osteoporosis (9.2%), hypothyroidism (9.2%), hypocortisolism (3.4%), and hypoparathyroidism (2.5%). All of which were statistically significant in their relationship to hemoglobinopathies with the exception of osteopenia and osteoporosis. Hypogonadism and hypocortisolism were found to be statistically significant in their relationship to a positive history of splenectomy at p=0.026 and p=0.012. Short stature was found to be statistically significant in its relationship to the male gender with a p=0.001. Conclusion: Endocrinopathy is a frequent complication of hemoglobinopathies, for which the most common were found to be short stature, diabetes mellitus,  and low bone mineral density.

Under-recognized Hypoparathyroidism in Thalassemia

OBJECTIVE

Symptomatic hypoparathyroidism [symptomatic hypocalcemia without elevated serum parathyroid hormone (PTH)] in patients with thalassemia is relatively rare. Asymptomatic mild hypocalcemia without elevated PTH, which is considered hypoparathyroidism, may be more common but under-recognized.

METHODS

Sixty-six transfusion-dependent thalassemic patients and 28 healthy controls were enrolled. Serum calcium (Ca), phosphate (P), creatinine (Cr), albumin, intact PTH, 25-hydroxyvitamin D (25-OHD), plasma intact fibroblast growth factor-23 (FGF-23), urinary Ca, P and Cr were measured. Tubular reabsorption of P was calculated.

RESULTS

Thalassemic patients had significantly lower median serum Ca levels than the controls [8.7 (7.8-9.7) vs 9.6 (8.7-10.1) mg/dL, p<0.001]. Hypoparathyroidism was found in 25 of 66 (38%) patients. Symptomatic hypoparathyroidism was not encountered. Thalassemic patients also had significantly lower median plasma FGF-23 levels than the controls [35.7 (2.1-242.8) vs 53.2 (13.3-218.6) pg/mL, p=0.01]. In patients with hypoparathyroidism, median plasma FGF-23 level was significantly lower than that of normoparathyroid patients [34.8 (2.1-120.0) vs 43.1 (3.2-242.8) pg/mL, p=0.048]. However, serum P, Cr, intact PTH and 25-OHD levels were not significantly different in the two groups.

CONCLUSION

Hypoparathyroidism was not uncommon in patients with transfusion-dependent thalassemia treated with suboptimal iron chelation. Plasma intact FGF-23 level in hypoparathyroid patients was lower than that of normoparathyroid patients.

Glucose Homeostasis Markers in Beta-Thalassemia

BACKGROUND

Glycosylated hemoglobin (HbA1c) has been a well-recognized marker of glucose homeostasis among thalassemics. Recently some studies have proposed the role of fructosamine as a better marker as compared with HbA1c. Hence, the study was carried out to find out which marker holds promise among Indian beta-thalassemic children.

METHODS

In this case-control study, 60 diagnosed cases of beta-thalassemia major and equal number of normal controls who were ≥8 years of age were enrolled. HbA1c, fructosamine, and fasting insulin levels were measured in all. Oral glucose tolerance test was done as a gold standard and the measured parameters were compared.

RESULTS

HbA1c was significantly higher in cases (7.10% [±0.47%]) than in controls (5.15% [±0.19%]) (P<0.001). Thalassemics with abnormal glucose tolerance had higher HbA1c level (7.34% [±0.57%]) than those with normal glucose tolerance (7.05% [±0.43%]) (P=0.05). Insulin resistance was noticed among thalassemics with abnormal glucose tolerance as compared with their normal counterparts (P=0.04). No significant difference was found in fructosamine levels between cases (239.80 [±31.80] μmol/L) and controls (234.10 [±21.34] μmol/L) (P=0.25) or between thalassemics with abnormal glucose tolerance (243.92 [±21.94] μmol/L) and their normal counterparts (238.77 [±33.93] μmol/L) (P=0.62).

CONCLUSIONS

The use of HbA1c as a diagnostic marker for diabetes in hemolytic anemias has to be done with caution as its baseline values are higher in them. Despite this finding, HbA1c continues to be a good marker for worsening glucose homeostasis in thalassemics as higher values were found in thalassemics with abnormal glucose tolerance compared with their normal counterparts. The present study did not find any relationship of fructosamine levels with impaired glucose tolerance in beta-thalassemia.

Adrenal insufficiency in non-transfusion-dependent α-thalassemia

BACKGROUND

Very few studies about adrenal insufficiency (AI) have been published with regard to non-transfusion-dependent (NTD) thalassemia, and none of those studies involved α-thalassemia patients. The aim of this study was therefore to determine the prevalence of AI in patients with NTD α-thalassemia, and to identify factors that predict the development of AI in this thalassemia subpopulation.

METHODS

This cross-sectional descriptive study was conducted in NTD α-thalassemic children at three referral hospitals in Thailand in 2015-2016. Preliminary screening for AI was done using the 1 μg adrenocorticotropic hormone (ACTH) stimulation test. Suspected AI was then confirmed on insulin tolerance test (ITT). AI was defined as peak cortisol <18 μg/dL. AI was categorized as either primary or secondary AI according to peak ACTH.

RESULTS

Thirty patients with NTD α-thalassemia were included in this study. Ten of 25 patients (40%) had abnormal initial screening. Eight of nine (88.9%) who underwent ITT were confirmed as having AI. No patients diagnosed with AI had any clinical symptoms of AI. The percentage of primary and secondary AI (n = 8) was 25% and 75%, respectively. Mean age and mean hemoglobin level showed a trend toward being associated with AI (P = 0.98).

CONCLUSION

The prevalence of biochemical AI in α-thalassemia patients was similar to rates previously reported for NTD β-thalassemia. Annual screening for AI in α-thalassemia patients is recommended, and glucocorticoid replacement should be considered in NTD α-thalassemia patients with AI during critical illness.

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

The variable presence of adrenal insufficiency (AI) due to hypocortisolemia (HC) in patients with thalassemia is well established; however, the prevalence of adrenocortical hypofunction (ACH) in the zona glomerulosa and zona reticularis of the adrenal cortex is unknown. To establish the prevalence of ACH, we examined the cortisol response to 1-µg and 250-µg ACTH tests, plasma aldosterone (A)/plasma renin activity (PRA) ratio, and serum dehydroepiandrosterone sulfate (DHEAS) levels in a large cohort of patients with thalassemia, and to investigate the impact of total body iron load (TBIL) on adrenocortical function. The setting used was University hospital and government-based tertiary care center. One hundred twenty-one (52 females) patients with β-thalassemia major (β-TM) and 72 healthy peers (38 females) were enrolled. The patients underwent a 250-µg cosyntropin test if their peak cortisol was <500 nmol/L in a 1-µg cosyntropin test. Magnetic resonance imaging (MRI) was performed to assess the MRI-based liver iron content and cardiac MRI T2* iron. The associations between ACH and TBIL were investigated. The patients with thalassemia had lower ACTH, cortisol, DHEAS, and A/PRA values compared with the controls (p < 0.001). Thirty-nine patients (32.2 %) had HC [primary (n = 1), central (n = 36), combined (n = 2)], and 47 (38.8 %) patients had reduced DHEAS levels; 29 (24.0 %) patients had reduced A/PRA ratios. Forty-six (38.0 %) patients had hypofunction in one of the adrenal zones, 26 (21.5 %) had hypofunction in two adrenal zones, and 9 (7.4 %) had hypofunction in all three zones. Patient age and TBIL surrogates were significant independent parameters associated with ACH. Cardiac MRI T2* iron was the only significant parameter that predicted the severity of ACH at a cut-off of 20.6 ms, with 81 % sensitivity and 78 % specificity. Patients with thalassemia have a high prevalence of AI due to HC and zona glomerulosa and zona reticularis hypofunction. TBIL surrogates can predict ACH, but cardiac iron was the only surrogate that was adequately sensitive to predict the severity of ACH.

Endocrinopathies in adolescents with thalassaemia major receiving oral iron chelation therapy

BACKGROUND

Endocrinopathies are common in patients with thalassaemia major (TM) despite parenteral iron chelation therapy with deferoxamine. There are only a few studies on the efficacy of oral deferiprone in preventing endocrine dysfunction.

AIM

To determine the growth and endocrine complications in children with TM receiving oral iron chelation with deferiprone.

METHODS

All adolescents with TM receiving regular blood transfusion and deferiprone were evaluated prospectively for growth and pubertal status over a 1-year period. Tests for endocrine function included oral glucose tolerance test, calcium, phosphate, alkaline phosphatase, parathyroid hormone and thyroid profile and, in those with delayed/arrested puberty, sex steroids and gonadotropins. Clonidine-stimulated growth hormone (GH) was measured in patients with height ≤-3 SD.

RESULTS

89 patients [51 males, 38 females, mean (SD) age 13·6 (2·5) years] were evaluated. Mean (SD) pre-transfusion haemoglobin was 9·2 (1·1) g/dl and the mean (SD) age of starting deferiprone was 5·1 (2·4) years. Mean (SD) ferritin was 9159 (3312) pmol/L (normal <2247). 49 (55%) subjects were of short stature and 25 (27%) had a height Z-score ≤ -3. GH testing was performed in 19 patients, of whom 17 had peak GH values <10 μg/L. Delayed puberty and/or hypogonadism was present in 54·1% patients at or beyond the age of normal puberty. Impaired glucose tolerance/diabetes mellitus, hypoparathyroidism and primary hypothyroidism (subclinical) were present in 13·0%, 10·1% and 8·9%, respectively. Overall, 44 (49·4%) adolescents had at least one endocrinopathy.

CONCLUSION

Adolescents with TM on oral iron chelation therapy with deferiprone experienced a high prevalence of growth faltering and endocrinopathies which was comparable to that previously reported with deferoxamine. A combination of deferoxamine and deferiprone may be necessary to prevent growth and endocrine problems.

Anti-Thyroid Peroxidase Antibodies and Male Gender Are Associated with Diabetes Occurrence in Patients with Beta-Thalassemia Major

BACKGROUND

Intensive transfusion schedule and iron-chelating therapy prolonged and improved quality of life in patients with β-thalassemia (β-T) major. However, this led to an increased risk of developing impaired glucose tolerance or diabetes. In this study we analyzed variables associated with the occurrence of impaired glucose tolerance or diabetes in patients with β-T major.

METHODS

388 Sardinian patients were included. Age, gender, duration of chelation therapy, body mass index, and markers of pancreatic and extrapancreatic autoimmunity were analyzed.

RESULTS

Multiple logistic regression analysis showed that anti-thyroid peroxidase (TPO) antibodies (Ab) (OR = 3.36; p = 0.008) and male gender (OR = 1.98; p = 0.025) were significantly associated with glucose impairment, while the other variables were not. Ferritin levels were significantly higher in TPOAb positive compared to TPOAb negative patients (4870 ± 1665 μg/L versus 2922 ± 2773 μg/L; p < 0.0001).

CONCLUSIONS

In patients with β-T major a progressive damage of insulin-producing cells due to secondary hemosiderosis appears to be the most reasonable mechanism associated with glucose metabolism disorders. The findings need to be confirmed with additional well designed studies to address the question of whether TPOAb may have a role in the management of these patients.

Prevalence of Hypoparathyroidism (HPT) in Beta Thalassemia Major

INTRODUCTION

The aim of this study was to assess the parathyroid functions and bone mineral density (BMD) in patients with beta thalassemia and to correlate them with serum ferritin, calcium, phosphorus and alkaline phosphatase levels.

MATERIALS AND METHODS

This is a case control study which was done on 55 subjects (40 cases and 15 controls) in the age group of 2-18 years. The cases included were with confirmed diagnosis of beta thalassemia major, more than ten blood transfusions and serum ferritin levels >2000 μg/L irrespective of chelation therapy.

RESULTS

Significant Hypoparathyroidism (HPT) observed along with low BMD levels in beta thalassemia patients (p < 0.01). A significant decrease in serum calcium level was seen in cases when compared to controls, where as the levels of both serum phosphorus and alkaline phosphatase levels increased in cases when compared to controls.

CONCLUSION

BMD and PTH levels are very useful tools for diagnosing HPT. As a routine, in beta thalassemia major, screening for vitamin D deficiency and hypocalcemia should be done in second decade of life and as a preventive measure they should be supplemented with calcium and vitamin D to prevent hypocalcemic tetany, to facilitate bone growth and to prevent fractures.

Adrenal insufficiency is prevalent in HbE/β-thalassaemia paediatric patients irrespective of their clinical severity and transfusion requirement

OBJECTIVES

Transfusion dependency is known to cause endocrinopathies in patients with thalassaemia such as adrenal insufficiency, because transfusion-related iron overload is injurious to endocrine organs. Children with HbE/ß-thalassaemia vary greatly in red cell transfusion requirement and some are transfusion dependent (TD), whereas others are nontransfusion dependent (NTD). Because iron overload is thought to be the primary cause of adrenal insufficiency, TD children with HbE/ß-thalassaemia are considered likely candidates for the development of adrenal insufficiency, while the adrenal function of NTD children is generally considered to be normal. As yet, the prevalence of adrenal insufficiency among children with NTD HbE/β-thalassaemia is not known. The present study was performed to (i) assess the prevalence of adrenal insufficiency in children with both TD and NTD HbE/β-thalassaemia and to evaluate whether there is any difference in the prevalence of adrenal insufficiency between both groups and (ii) determine the type of adrenal insufficiency (primary or secondary).

METHODS

We investigated the prevalence of adrenal insufficiency among TD (n = 42) and NTD (n = 43) children with HbE/β-thalassaemia by assessing morning serum cortisol levels, and we distinguished between primary and secondary adrenal insufficiency by assessing the cortisol responses following the 1- and 250-μg ACTH stimulation tests.

RESULTS

The prevalence of adrenal insufficiency among TD and NTD children with HbE/β-thalassaemia was 50% and 53·5%, respectively. By using the 250-μg ACTH stimulation test, at least 39% and 23·5% were diagnosed with adrenal gland hypofunction in TD and NTD children, respectively.

CONCLUSION

This is the first study to show that adrenal insufficiency is common among all children with HbE/β-thalassaemia, irrespective of their transfusion history or requirement. Our findings have important implications for the clinical management of these children.

Cortisol response to low dose versus standard dose (back-to-back) adrenocorticotrophic stimulation tests in children and young adults with thalassemia major

BACKGROUND

Thalassemia major patients with repeated blood transfusion have high prevalence of endocrinopathies due to iron overload.

MATERIALS AND METHODS

We examined the adrenocortical function in 23 thalassemic patients (10 children and 13 young adults) aged 8-26 years. Serum cortisol and dehydroepiandrosterone sulfate (DHEA-S) concentrations were determined in each subject before blood transfusion both in basal condition and after low dose (LD) (1 μg), followed by standard dose (SD) (250 μg, respectively) with synthetic corticotrophin beta 1-24 ACTH (Synacthen, Ciba). Normal controls were a group of 13 age- and sex-matched normal subjects.

RESULTS

Using a peak total cortisol cutoff level of 550 nmol/L and increments of 200 μg above basal cortisol, adrenal insufficiency (AI) was demonstrated in 8 patients (34.7%) after the LD ACTH and in 2 patients (8.7%) after SD cosyntropin (ACTH) test, but none of the controls. Using a peak total cortisol cutoff level of 420 nmol/L and increments of 200 μg above basal cortisol, AI was demonstrated in 5 patients (21.7%) after the LD ACTH and in 2 patients after SD ACTH test (8.7%), but none of controls. All patients with biochemical AI were asymptomatic with normal serum sodium and potassium concentrations and had no history suggestive of adrenal pathology. The peak cortisol concentrations in thalassemic patients with impaired adrenal function both after 1 μg and 250 μg cosyntropin (294 ± 51 nmol/L and 307 ± 58.6) were significantly lower than those with patients with normal (454 ± 79.7 nmol/L and 546.1 ± 92.2 nmol/L, respectively) and controls (460.2 ± 133.4 nmol/L and 554.3 ± 165.8 nmol/L, respectively). Adolescents and young adults, but not children with thalassaemia, had significantly lower peak cortisol concentration after SD ACTH versus controls. Peak cortisol response to LD ACTH was correlated significantly with peak cortisol response to SD in all patients (r = 0.83, P < 0.0001). In adolescents and young adults with thalassemia, DHEA-S levels before and after LD ACTH stimulation were significantly lower and the cortisol/DHEA-S ratios were significantly higher than the controls.

CONCLUSION

The use of LD ACTH test diagnoses more adrenal abnormalities versus SD ACTH in thalassemic patients. The relatively high prevalence of AI in thalassemic adolescents and young adults necessitates that these patients have to be investigated for AI before major surgery and those with impaired cortisol secretion should receive stress doses of corticosteroids during the stressful event.

Causes for hospitalization and death in Iranian patients with β-thalassemia major

There are limited studies that have focused on the causes for hospitalization as an indicator of morbidity in patients with β-thalassemia major (BTM). A cross-sectional study was conducted to determine the main causes for hospitalization and death in hospitalized BTM patients in a referral hospital in Shiraz, southern Iran. During a 5-year period, 555 BTM patients were admitted to the hospital, of which 390 (67.7%) were 10 to 20 years of age. The most frequent causes for hospitalization were splenectomy (23%), heart failure (22.6%), liver biopsy (22.2%), uncontrolled diabetes (10.9%), arrhythmia (7.2%), cholecystectomy (3.8%), hypoparathyroidism (2.1%), and sepsis (2%). Of the hospitalized patients, 65 (11%), with a mean age of 16.1 ± 4.2 years, died. The most common causes of death were cardiomyopathy (72.3%), infections (17%), malignancies (3.1%), and cerebrovascular accidents (3.1%). Survival of our patients was less than in developed countries and cardiac complications were the most common cause of mortality and morbidity in these patients. Regarding the key role of iron chelation in prevention of different complications in BTM, correction of iron chelation regimen should be well considered.

High prevalence of "biochemical" adrenal insufficiency in thalassemics: is it a matter of different testings or decreased cortisol binding globulin?

CONTEXT

High prevalence of "biochemical" adrenal insufficiency (AI) in thalassemics has been reported. However, "clinical" AI is rare.

AIM

The aim was to determine whether cortisol binding globulin (CBG) or tests used in assessing adrenal function contributed to the abnormally high prevalence of biochemical AI.

SETTING

The study was conducted at Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.

PARTICIPANTS

Participants included 56 children and adolescents with thalassemia and 44 controls.

MAIN OUTCOME MEASURES

Serum CBG and adrenal function test results assessed by 1 μg cosyntropin test and insulin tolerance test (ITT) were measured. Free cortisol index (FCI) calculated by total cortisol (TC)/CBG and calculated free cortisol (cFC) were determined.

RESULTS

Mean (sd) CBG levels were comparable between patients and controls [45.2 (11.0) vs. 47.0 (8.6) mg/liter]. Peak TC, FCI, and cFC after cosyntropin test were lower in thalassemics [TC, 15.2 (4.0) vs. 18.9 (3.1) μg/dl; FCI, 3.4 (0.8) vs. 4.2 (1.2) μg/mg, P <0.001; and cFC, 1.03 (0.38) vs. 1.44 (0.61) μg/dl, P = 0.008]. Thirty of 56 thalassemics (53.6%) had AI, defined as having peak TC of less than 16 μg/dl. ITT was performed in 26 of those 30 patients. Five of 26 patients had peak TC after an ITT of at least 20 μg/dl. As a result, the estimated frequency of AI in the entire patient group was reduced by approximately 10%.

CONCLUSION

The 1 μg cosyntropin test could be an adrenal function screening test in thalassemics. However, for definite diagnosis, ITT should be performed in those having peak total cortisol of less than 16 μg/dl after the 1 μg cosyntropin test.

Case Study: using a continuous glucose monitoring system in a patient with diabetes and beta-thalassemia hemoglobinopathy

Optimum glycemic control is extremely important in patients with diabetes mellitus to avoid long-term complications. Glycemic control relies mainly on the use of hemoglobin A1c, which unfortunately showed inaccurate results in patients with hemoglinopathies. The authors describe a case of beta-thalassemia with poorly controlled diabetes mellitus that has misleading low levels of HbA1c. The use of a continuous glucose monitoring system was useful in documenting her poor glycemic control, with prolonged periods of hyper- and hypoglycemia. Based on these results, her insulin regimen was adjusted and the blood glucose levels were greatly improved throughout and the patient was able to meet her target blood glucose range (72-140 mg/dL [4-7.8 mmol/L]) in 70% of the time.

Assessment of puberty in relation to L-carnitine and hormonal replacement therapy in beta-thalassemic patients

OBJECTIVE

To investigate puberty in a group of thalassemic patients with delayed or arrested pubertal development and to compare the effects of hormonal and L-carnitine therapy on puberty in those patients.

PATIENTS

Thirty-two -thalassemic patients with arrested or failure of puberty were enrolled for 1 year in this study.

METHOD

Clinical pubertal assessment and laboratory investigations were done for all patients at the beginning, 6 months later clinical pubertal assessment was done. Patients were divided into two groups (16 each): first group received L-carnitine therapy, while the second group received hormonal therapy. Pubertal and laboratory assessment were done 6 months after hormonal and L-carnitine therapy.

RESULTS

Failure of puberty was confirmed in 71.4% of boys and 33.3% of girls, while arrested puberty was observed in 28.6% of boys and 66.7% of girls. All girls had amenorrhea, primary amenorrhea in 88.9% and secondary amenorrhea in 11.1%. Menses occurred in 20% of female patients after L-carnitine therapy and in 37.5% of them after hormonal therapy. Improvement of pubertal staging was observed in 50% of males after L-carnitine therapy compared to 75% of them after hormonal therapy. While improvement of pubertal staging was seen in 90% of females after L-carnitine therapy compared to 100% of females after hormonal treatment. However, these results showed no significant difference between both groups.

CONCLUSION

Delayed puberty in beta-thalassemia major is either due to failure of gonads or failure of the whole hypothalamic pituitary gonadal axis. L-carnitine as well as hormonal replacement therapy had a positive effect on puberty in the thalassemic patients. Further studies are needed to clarify the role of L-carnitine on puberty in these patients.

Prevalence of impaired glucose metabolism in beta-thalassemic children receiving hypertransfusions with a suboptimal dosage of iron-chelating therapy

A cross-sectional study of impaired glucose metabolism was carried out in 48 beta-thalassemic patients receiving hypertransfusions. An oral glucose tolerance test (OGTT) was performed using the method and criteria of the American Diabetes Association (ADA). Diabetes mellitus was diagnosed in two patients, and impaired glucose tolerance was found in four patients, giving a prevalence of impaired glucose metabolism of 12.5% in our patient population. The significant clinical characteristics associated with the diagnosis of impaired glucose metabolism were wasting (-2.15/-0.86 SDS, p = 0.025), stunting (-2.69/-1.22 SDS, p = 0.03), higher ferritin levels (8679/4710 microg/L, p = 0.005), splenectomy (50/9.5%, p = 0.012), and lower area under curve (AUC) of insulin secretion after OGTT (40.0/77.7, p = 0.002). The significant decrease of AUC insulin in thalassemic patients with an impaired glucose tolerance test suggests that the pathogenesis may originate from pancreatic beta-cell damage rather than from insulin resistance. In conclusion, the prevalence of impaired glucose tolerance in our population of thalassemic patients receiving hypertransfusions with suboptimal iron chelating therapy was 12.5%. The clinical characteristics of thalassemic patients who developed impaired glucose tolerance were wasting, stunting, higher ferritin levels, splenectomy, and lower AUC insulin.

Endocrinopathies in patients with transfusion-dependent beta-thalassemia

Thalassemia is common in Iran. Appropriate therapy for this disease includes a regular blood transfusion and chelation therapy. However, in this approach patients will inevitably experience side effects, particularly iron overloads in critical organs, including heart, ductless glands, and liver. This study attempted to determine prevalence of adenoidal abnormality between Iranian thalassemia patients for prediagnosis and to offer necessary medical measures. This is a descriptive nonrandomized study and included all the patients suffering from thalassemia major referring to medical centers linked with the Iranian blood transfusion organization from January 2004 to January 2005. All patients were sampled for CBC, FBS, 2-h BS, HbAlC, liver function, renal function, and endocrine disease. Initially, reports of adenoidal experiments as well as other associated parameters were provided from medical records. A total of 437 patients enrolled in the study: 5.4% suffered from diabetes, 1% had hypothyroid, and 1 person showed hypoparathyroidism. The mean levels of ferritin in diabetic and nondiabetic groups and hypothyroid and nonhypothyroid groups were not significantly different. The mean levels of ferritin among various age groups also were not significantly different. Results of a comparison between present research and similar studies conducted throughout Iran and those performed abroad on adenoidal abnormalities in thalassemia patients show that subject patients of this study statistically suffered from fewer difficulties than diabetes patients in other studies.

Update on thalassemia: clinical care and complications

beta-Thalassemia, originally named Cooley anemia, is an inherited blood disease. Various types of thalassemia are inherited anemias caused by mutations at the globin gene loci on chromosomes 16 and 11, affecting the production of alpha- or beta-globin protein, respectively. The combination of early diagnosis, improvements in monitoring for organ complications, and advances in supportive care have enabled many patients who have severe thalassemia syndromes to live productive, active lives well into adulthood.

Beta thalassemia and energy consumption in hemoglobin A1C formation: a model

Hemoglobin (Hb) A1C is the nonenzymatic glycated product of the Hb beta chain at the valine terminal residue. Recently, the nature of energy-consuming reaction in HbA1C formation was reported, and this was proposed as an underlying pathophysiology for poor nutritional status, muscle loss, and functional impairment in poor-control diabetic patients. Here, the author focuses on energy change in HbA1C formation in the case of beta thalassemia. According to this study, the energy range required for any type of beta thalassemia is greater than that required for normal Hb. Hence, it might be expressed that beta thalassemia did significantly increase complications due to energy consumption during HbA1C formation in poor-control diabetic cases.

The impact of genotype on endocrine complications in thalassaemia major

BACKGROUND

The clinical severity in thalassaemia major (TM) depends on the underlying mutations of the beta-globin gene and the degree of iron overload.

OBJECTIVE

The aim of the study was to investigate the impact of genotype on the development of endocrine complications in TM in our center.

SUBJECTS AND METHODS

126 (62 males, 64 females) thalassaemic patients of Greek Cypriot origin with a mean age of 31.2 (17-68) yr were included in the study. All patients, who were on the standard treatment protocol, were subsequently divided into two groups according to their genotype, group A (92): TM with no mitigating factor and group B (34): TM carrying one or more mitigating factors in the beta- and/or alpha-globin genes. Iron overload calculation was based on the amount of red cell consumption and the mean ferritin level over a 12-year period. Statistical analysis was performed with the SPSS program.

RESULTS

Patients in group A, who were consuming larger amounts of blood on transfusions, were more likely to develop hypogonadism (P = 0.001) compared with patients in group B, despite their similar mean ferritin levels. The incidence of other endocrinopathies (short stature, hypothyroidism, and diabetes mellitus) was similar in the two groups. The prevalence of hypothyroidism in splenectomized patients was significantly higher (P = 0.005), whereas the presence of hypogonadism, impaired glucose homeostasis and insulin resistance, although more frequent, was not statistically significant. The clinical severity of TM had no impact on bone mineral density (BMD) in both men and women. BMD was only influenced by gonadal function.

CONCLUSIONS

This study demonstrates that the underlying genetic defect in TM is a contributing factor for gonadal dysfunction, because the patients with the more severe defects have a greater rate of iron loading through higher red cell consumption.

Hypoparathyroidism in transfusion-dependent patients with beta-thalassemia

Hypoparathyroidism is thought to be a rare consequence of iron overload seen in beta-thalassemic transfused patients. This study was conducted to determine the prevalence of hypoparathyroidism in a large number of beta-thalassemic patients, and its potential correlation with the presence of other endocrinopathies caused by iron overload. Serum and urine biochemical parameters were measured in 243 thalassemic patients (136 females and 107 males) in order to determine the prevalence of hypoparathyroidism and evaluate bone turnover. The patients were divided into two groups according to the presence of hypoparathyroidism. We compared the prevalence of other endocrinopathies and disease complications in the two groups. Hypoparathyroidism was detected in 13.5% of the patients (33 subjects; 17 males and 16 females). Serum-intact parathyroid hormone, and total and ionized calcium were significantly lower, while phosphorus was significantly higher in thalassemic patients with hypoparathyroidism. The reduction in BMD was more prominent in normal thalassemic patients (Z score = -2.246 +/- 0.97) compared with those with hypoparathyroidism (Z score = -1.975 +/- 0.89), although the difference was not statistically significant. Disturbed glucose metabolism was more common in patients with hypoparathyroidism (P < 0.05). In addition, heart dysfunction was statistically more frequent in this group (odds ratio = 2.51, P < 0.05). Hypoparathyroidism is a not infrequently observed complication in thalassemic patients. Since the concentration of ferritin is not a valuable tool in the prediction of the development of hypoparathyroidism, parathyroid function should be tested periodically, particularly when other iron overload-associated complications occur.

Hydrops fetalis caused by homozygous alpha-thalassemia and Rh antigen alloimmunization: report of a survivor and literature review

Hematologic causes of hydrops fetalis include homozygous alpha-thalassemia and immune hemolytic anemias. We report the case of a boy with hydrops fetalis who had homozygous alpha-thalassemia and alloimmune hemolytic anemia due to anti-E and anti-C blood group antibodies. He received intrauterine red blood cell transfusions and postnatal chronic transfusion with iron chelation therapy. A non-myeloablative sibling stem cell transplant failed. He is now 5 years and 6 months of age, hypothyroid with short stature, but in overall good health. He is one of the oldest reported homozygous alpha-thalassemia survivors and, to our knowledge, the only survivor with immune- and nonimmune-induced hydrops fetalis.