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L
ate
-
onset
hypogonadism
or
ADAM:
diagnosis
R
ev
A
ssoc
M
ed
B
ras
2014; 60(4):286-294
291
EquilibriumDialysis is the gold standard for the mea-
surement of free testosterone, but it takes time and is
technically complicated, being thus used only in reference
laboratories
18
(
A
). International reference standards, cha-
racterization of methodology and reference ranges based
on populations for measurement of FT using equilibrium
dialysis are required
30
(
B
).
On the other hand, measuring SHBG in the serum to-
gether with a reliable determination of TT provides suf-
ficient data to calculate FT levels. Calculated FT correlates
well with FT using equilibrium dialysis
31
(
D
). Consensus
in relation to the equilibrium constants for testosterone
binding to SHBG and albumin will allow advancements
in the calculations of FT. For example, a study compa-
ring five algorithms published for the calculation of FT
concluded that these should be reevaluated at each loca-
tion, otherwise values much higher or lower than the re-
ference values could occur
34,35
(
B
).
In the United States, representatives of various pro-
fessional societies, the government and industry met in
February of 2010 with the objective of ensuring that tes-
tosterone levels are measured with precision and reliabi-
lity, identifying the targets objectives and actions requi-
red for standardization of testosterone measurements.
Results:
a series of recommendations were made
to ensure very precise testosterone measurements that
will result in more adequate diagnoses, treatments and
prevention through the use of standardized testoste-
rone tests. The recommendations included technical
improvements in the standardization of tests; educa-
tion of health workers, patients and others involved in
testosterone measurement; plans to encourage publi-
cations; government agencies and health insurers in-
volved to support this effort; and encouragement for
manufacturers to develop better and more economi-
cally viable measurements. Some of these actions are
already underway
36
(
D
).
Recommendation
The gold standard for total testosterone measurement
is LC-TM/MS (liquid chromatography–mass spectro-
metry in tandem), and reliable reference ranges for to-
tal serum testosterone using this method are being de-
veloped. These should be validated for an international
reference. Standardization is crucial for the improve-
ment of patient care. Equilibrium dialysis is the gold
standard for measurement of free testosterone, though
it is time consuming and technically complicated. In-
ternational reference standards, characterization of me-
thodology and reference ranges based on populations
for measurement of free testosterone using equilibrium
dialysis are required. Consensus in relation to the equi-
librium constants for testosterone binding to SHBG
and albumin will allow advancements in the calcula-
tions of free testosterone.
W
hich
examinations
should
be
requested
before
the
start
of
ART?
Baseline testosterone measurement: the reference ranges
and measurements methods have already been covered
in previous questions.
Lipid evaluation: in a recent meta-analysis with good
evidence of 11 studies on the adverse effects of ART, 4 stu-
dies showed a reduction in HDL, while 7 showed no sig-
nificant change
37
(
A
).
Prostate assessment: baseline PSA measurement and
rectal exam should be conducted on all patients aged 40
or over. Prostate biopsy should be indicated in cases of
suspected prostate cancer suggested by alterations to the
touch and/or PSA levels.
Only patients with light or moderate urinary tract
symptoms or negative biopsy for prostate carcinoma
should be treated
38
(
B
).
Baseline measurement of hematocrit: the admi-
nistration of testosterone in hypogonadic men is as-
sociated with a dose-dependent increase in hemoglo-
bin. The increase in hemoglobin is higher in older men.
Men with baseline hematocrit over 50% should be sub-
mitted to an accurate clinical assessment before con-
sidering ART
38
(
B
).
Disregard history of sleep apnea: the frequency of
men with a new diagnosis of sleep apnea during ART
is not statistically significant
37
(
A
). Cases of obstructive
sleep apnea should be treated before starting ART
39
(
B
).
Recommendation
The following procedures are recommended: lipid eva-
luation, baseline PSA level, baseline hematocrit level, dis-
regard history of sleep apnea.
H
ow
should
the
patient
undergoing
ART
be monitored with
regard
to
the
frequency
of
consultations
?
Consultations should be held every three or six months
after starting treatment, and then annually to evaluate if
the symptoms have responded to treatment or if the pa-
tient is having any adverse effects.
The patient should be questioned about urinary tract
symptoms and sleep apnea. During the physical exami-
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