Ironjustic
Mon, Aug-14-06, 06:15
Iron pituitary load leads to fatigue and / or tiredness ..
WITH .. what seems to be LOW iron ..
<<snip>> A pituitary magnetic resonance scan may be considered
as an investigation to visualize pituitary iron overload It
may be noted that thalassaemics who are growth hormone
deficient from pituitary iron deposition, have relatively low
ferritin levels <<snip>>
Letters to the Editor
Indian Pediatrics 2005; 42:843-844
Polytransfused Children with Beta Thalassemia Major have Wider
Endocrine Dysfunction
We read with interest the brief report entitled "Assessment
of adrenal endocrine function in Asian Thalassemics"(1). A
large number of children in India undergo long term
transfusions and are therefore at risk of
hypothalamo-pituitary dysfunction. The paper makes an
important observation of detecting biochemical evidence of
adrenal hypofunction in polytransfused patients.
The authors describe a low dose (1 micro-gram) and a
standard dose (250
microgram) ACTH stimulation test to assess adrenal function.
However neither test discriminates between primary (adrenal
gland) and secondary (hypothalamus, pituitary gland) adrenal
hypofunction. Given that children with beta thalassaemia are
more likely to have pituitary malfunction, serum ACTH
estimation should be an additional useful test.
A significant proportion of thalassemics have
hypogonadotrophic hypogonadism and therefore remain
prepubertal in sexual maturation. Delayed puberty itself may
partly account for the reduction in weight for age. Of course,
other variables such as nutrition, socio-economic status,
parental build and ethnic background may also be responsible
for small body size. Puberty is an important process not only
for sexual maturation but also for bone mineralisation.
Puberty should therefore be assessed in all children and the
gonadotrophin releasing hormone test performed in those with
poor progression.
Iron overload from polytransfusions is well known to cause
pituitary failure. The authors measured serum ferritin as an
index of iron overload but found no significant correlation
with basal cortisol concentrations. It may be noted that
thalassaemics who are growth hormone deficient from pituitary
iron deposition, have relatively low ferritin levels(2) and
this may account for the lack of association.
We should be alert to the real possiblity of growth hormone
deficiency,
hypogonadot-rophic hypogonadism, hypothyroidism and
hypoparathyroidism in all beta thalassaemia children
undergoing regular transfusions. In addition to basal cortisol
and ACTH, it is important to assess thyroid function,
parathyroid hormone and insulin like growth factor-1(IGF-1) in
these children. Dual energy X-ray absorptiometry (DXA) scans
may be performed
where there are adequate resources to assess bone mineral
density. Children in growth failure should have a low
threshold for undergoing pituitary function tests. Those
complaining of tiredness or fatiguability should be
investigated with the low dose ACTH test for adrenal reserve.
A pituitary magnetic resonance scan may be considered as an
investigation to visualize pituitary iron overload(3).
I. Banerjee, Department of Pediatric Endocrinology, Royal
Manchester Children's Hospital, United Kingdom. E-mail:
ibanerjee@freeuk.com
References
1. Srivatsa A, Marwaha RK, Muralidharan R, Trehan A.
Assessment of adrenal endocrine function in Asian
Thalassemics. Indian Pediatrics 2004; 42: 31-35.
2. Masala A, Atzeni MM, Alagna S, Gallisai D, Burrai C, Mela
MG, et al.
Growth hormone secretions in polytransfused prepubertal
patients with homozygous beta thalassemia. Effect of long term
recombinant growth hormone (rec GH) therapy. J Endocrinol
Invest 2003; 26: 623-628.
3. Argyropoulou MI, Metafratzi Z, Kiortsis DN, Bitsis S,
Tsatsoulis A, Efremidis S. T2 relaxation rate as an index
of pituitary iron overload in patients with
beta-thalassemia major. AJR Am J Roentgenol. 2000; 175:
1567-1569.
Who loves ya. Tom
Jesus Was A Vegetarian! http://jesuswasavegetarian.7h.com
Man Is A Herbivore! http://tinyurl.com/a3cc3
DEAD PEOPLE WALKING http://tinyurl.com/zk9fk
WITH .. what seems to be LOW iron ..
<<snip>> A pituitary magnetic resonance scan may be considered
as an investigation to visualize pituitary iron overload It
may be noted that thalassaemics who are growth hormone
deficient from pituitary iron deposition, have relatively low
ferritin levels <<snip>>
Letters to the Editor
Indian Pediatrics 2005; 42:843-844
Polytransfused Children with Beta Thalassemia Major have Wider
Endocrine Dysfunction
We read with interest the brief report entitled "Assessment
of adrenal endocrine function in Asian Thalassemics"(1). A
large number of children in India undergo long term
transfusions and are therefore at risk of
hypothalamo-pituitary dysfunction. The paper makes an
important observation of detecting biochemical evidence of
adrenal hypofunction in polytransfused patients.
The authors describe a low dose (1 micro-gram) and a
standard dose (250
microgram) ACTH stimulation test to assess adrenal function.
However neither test discriminates between primary (adrenal
gland) and secondary (hypothalamus, pituitary gland) adrenal
hypofunction. Given that children with beta thalassaemia are
more likely to have pituitary malfunction, serum ACTH
estimation should be an additional useful test.
A significant proportion of thalassemics have
hypogonadotrophic hypogonadism and therefore remain
prepubertal in sexual maturation. Delayed puberty itself may
partly account for the reduction in weight for age. Of course,
other variables such as nutrition, socio-economic status,
parental build and ethnic background may also be responsible
for small body size. Puberty is an important process not only
for sexual maturation but also for bone mineralisation.
Puberty should therefore be assessed in all children and the
gonadotrophin releasing hormone test performed in those with
poor progression.
Iron overload from polytransfusions is well known to cause
pituitary failure. The authors measured serum ferritin as an
index of iron overload but found no significant correlation
with basal cortisol concentrations. It may be noted that
thalassaemics who are growth hormone deficient from pituitary
iron deposition, have relatively low ferritin levels(2) and
this may account for the lack of association.
We should be alert to the real possiblity of growth hormone
deficiency,
hypogonadot-rophic hypogonadism, hypothyroidism and
hypoparathyroidism in all beta thalassaemia children
undergoing regular transfusions. In addition to basal cortisol
and ACTH, it is important to assess thyroid function,
parathyroid hormone and insulin like growth factor-1(IGF-1) in
these children. Dual energy X-ray absorptiometry (DXA) scans
may be performed
where there are adequate resources to assess bone mineral
density. Children in growth failure should have a low
threshold for undergoing pituitary function tests. Those
complaining of tiredness or fatiguability should be
investigated with the low dose ACTH test for adrenal reserve.
A pituitary magnetic resonance scan may be considered as an
investigation to visualize pituitary iron overload(3).
I. Banerjee, Department of Pediatric Endocrinology, Royal
Manchester Children's Hospital, United Kingdom. E-mail:
ibanerjee@freeuk.com
References
1. Srivatsa A, Marwaha RK, Muralidharan R, Trehan A.
Assessment of adrenal endocrine function in Asian
Thalassemics. Indian Pediatrics 2004; 42: 31-35.
2. Masala A, Atzeni MM, Alagna S, Gallisai D, Burrai C, Mela
MG, et al.
Growth hormone secretions in polytransfused prepubertal
patients with homozygous beta thalassemia. Effect of long term
recombinant growth hormone (rec GH) therapy. J Endocrinol
Invest 2003; 26: 623-628.
3. Argyropoulou MI, Metafratzi Z, Kiortsis DN, Bitsis S,
Tsatsoulis A, Efremidis S. T2 relaxation rate as an index
of pituitary iron overload in patients with
beta-thalassemia major. AJR Am J Roentgenol. 2000; 175:
1567-1569.
Who loves ya. Tom
Jesus Was A Vegetarian! http://jesuswasavegetarian.7h.com
Man Is A Herbivore! http://tinyurl.com/a3cc3
DEAD PEOPLE WALKING http://tinyurl.com/zk9fk