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Adrenal Reserved Function In Asthmatic Children
Treated With Inhaled Fluticasone
Mahidol University Annual Research Abstracts 2000
129 We studied 19 patients with thalassemia diseases
(TD) and 20 children with thalassemic traits (TT).
Mean bone age SDS was -2.73 (range -4.75 to 0.28)
in TD whereas that in TT was -0.97 (range -3.77
to 1.59). Bone mineral density (BMD) was determined
by dual x-ray absorptiometry (DEXA). In TD, median
radius, femoral neck, and lumbar BMD SDS were
-0.85, -1.44 and -3.15, respectively whereas in
TT, those were within +1. Anterior iliac bone
biopsy was performed for evaluation of histology
and histomorphometry. Bone histology revealed
increased osteoid thickness and iron deposit in
trabecular surface, cement lines and calcification
fronts. Osteoclasts and erosion surface were rarely
seen in bone sections. In conclusion, delayed
bone age and reduced BMD were common findings
in thalassemic bones. Bone histology demonstrated
iron deposit, thick osteoid and reduced erosion
surface. These findings suggest that there may
be delayed bone mineralization and reduced bone
resorption in thalassemic bones.
Evaluation of bone histomorphometry is required
to support these findings. However, the cellular
interactions among hematopoietic and bone cells
are not yet known and being studied. ADRENAL RESERVED
FUNCTION IN ASTHMATIC CHILDREN TREATED WITH INHALED
FLUTICASONE Mahachoklertwattana Cortisol is an
essential endogenous steroid. It affects the metabolism
of most tissues. Cortisol synthesis is regulated
primarily by pituitary corticotropin (ACTH), with
cortisol exerting negative feedback on ACTH secretion.
Exogenous steroid administration can suppress
pituitary-adrenal axis. Inhaled steroids are increasingly
used in the prophylaxis and treatment of asthmatic
attack.
Fluticasone is a new potent inhaled synthetic
steroid. The systemic side effect of inhaled fluticasone
on adrenal reserved function in asthmatic children
is not yet well documented. : To assess adrenal
reserved function in asthmatic children treated
with inhaled fluticasone. Methods and subjects
: Children were diagnosed with asthma by history,
physical examination and methacholine challenge
test. All were treated with inhaled fluticasone
250-750 mmg/day via standard spacer for 5-16 weeks.
Insulin-induced hypoglycemia test (IHT) was performed
to assess adrenal reserved function. Criterion
for adrenal suppression is a peak serum cortisol
of less than 18 mmg/dl. Eighteen asthmatic children
(10 boys, 8 girls) aged 7-17 years (median age
11 years) were taking inhaled fluticasone at the
median dose of 477.3 mmg/m2/day. Adrenal suppression
was found in 9 children (50%).
The median basal and peak serum cortisol of suppressed
group were 4.9 and 12.7 mmg/dl, and of non-suppressed
group were 8.8 and 20.5 mmg/dl respectively. Seven
children in the suppressed group had repeated
IHT after reducing the dose of fluticasone. All
had normal adrenal reserved function. Transient
adrenal suppression was evident in 50 per cent
of asthmatic children treated with approximately
500 mmg/m2/day of inhaled fluticasone. Therefore,
evaluation of adrenal function is necessary in
children treated with prolonged inhaled fluticasone.
In stress situation, to prevent adrenal crisis,
treatment with stress dose of glucocorticoid is
recommended.
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