Treatment:
Anemia, folate deficiency
and hypersplenism are traditional causes of poor growth in patients with beta
TM receiving irregular transfusion, as well as those regularly using DFX. In
peri-pubertal patients, hypogonadism should be carefully investigated before
starting growth hormone treatment which may result in decreased insulin
sensitivity and abnormal glucose tolerance. Oral zinc sulphate supplementation
should be given in patients with proven zinc deficiency (De Sanctis,
1999).
Delayed puberty and hypogonadism
Delayed puberty and
hypogonadism are the most obvious clinical sequences of iron overload. Delayed
puberty is defined as the complete lack of development in girls by the age of
13 years, and in boys by the age of 14 years. Arrested puberty is a relatively
common complication in moderately or grossly iron overloaded patients with
thalassemia, and is characterized by lack of pubertal progression over a year
or more (DeSanctis, 1995).
Most women with thalassemia
major present primary amenorrhea, with secondary amenorrhea developing over
time particularly in poorly chelated patients. Ovarian function in such
patients is generally normal but gonadotrophin response to (GnRH) is low compared
to patients with normal menstrual cycles (De Sanctis, 1995).
Hypogonadotropic hypogonadism is due to
damage from iron deposition in the hypothalamus and pituitary gland but
occasionally primary gonadal failure can also occur. The pituitary gonadotropes
are particularly sensitive to oxidative damage induced by iron overload.
Magnetic resonance imaging (MRI) of the anterior pituitary has shown that a
decrease in signal intensity of spin-echo images of the pituitary is associated
with increasing iron deposition in the anterior pituitary, and may be a useful
investigative tool in the assessment of pituitary hemosiderosis. It has been
shown that the gonadotropin response to gonadotropin releasing hormone
stimulation is correlated with the grading of MRI-assessed iron deposition in
the pituitary gland (Berkovitch et al., 2000).
It has also been
shown recently that patients with certain globin gene mutations (homozygous or
double heterozygous mutation for 39 and IVSInt110) may be particularly
susceptible to the development of hypogonadism due to iron overload (Raiola
et al., 2003).
ليست هناك تعليقات:
إرسال تعليق