5. Ayala, A. R., Nisala, B. C., Chen, H. C., et
al., Highly sensitive radioimmunoassay for
chorionic gonadotropin in human urine. J.
Clin. Endocrinol.
Metab.
46, 767-773
Table 1. Summary of Cross Reactivity Studies
BhCG. Int. units/L
Radloassays
LH, ml. unltslL
Systems
Laboratories
Amedcan Diagnostic hCO
Old
New
Old
New
Clinical
Assays
(1978).
6. Vaitukaitis, J. L., Braunstein, G. D., and
Ross, G. T., A radioimmunoassay which
specifically measures human chorionic gonadotropin in the presence of human luteinizing hormone. Am. J. Obstet. Gynecol.
Diagnostic Products calibrators
3
6.3
2.0
10
20
14.2
113,751-758(1972).
8.3
5.6
7. Knox, B. S., McKee, J. W. A., Haii, P. I.,
and Lance, J. T., Determination of $-choriogonadotropin
in human plasma: Evaluation and comparison of five “kit” methods.
Clin. Chem. 26,1890-1895
(1980).
8. Catatona, W. J., Vaitukaitis, J. L., and
Fair, W. R., Falsely positive specific human
chorionic gonadotropin assays in patients
with testicular tumors: Conversion to negative with testosterone administration. J.
Urol. 122,126-128 (1981).
9. Vining, K F., Compton, P., and McGinley,
R., Steroid radioimmunoassay-effect of
shortened incubation time on specificity.
Clin. Chem. 27,910-913 (1981).
10.3
40
80
20.8
200
35.9
6.8
32.8
17.6
9.6
National Pituitary Agency LH
66.3
132.5
7.2
13.2
265
24.2
16.6t’
530
38.2
2S.l’
4-h incubation.
b
5.0
b
24-h incubation.
ing Diagnostic Products human LH
calibrators
and National
Pituitary
Agency human LH by the American
Diagnostics, Radioassay Systems Lab-
oratories, and Clinical Assays flhCG
kits, both before and after methodology
changes by the manufacturers. Significant cross reactivity was seen with both
LH preparations when assayed with the
“old” American Diagnostics kit; moreover, the current American Diagnostics
kit, offered as either a 4-h or an 24-h
incubation procedure, also yielded erroneous results, although with the 4-h
incubation, cross reactivity was only
slight This variation between the 4-h
and 24-h procedures may be an indication that equilibrium of the reaction
mixtures was not complete at 4-h (9).
The “old” Radioassay
Systems Laboratories kit also exhibited some random
cross reactivity with the Diagnostic
Products calibrators, but not with either
LH preparation by the current kit. The
Clinical Assays kit showed minimal
cross reactivity.
The extent of cross reactivity between
t9hCG and LH seen with both the previous and current American Diagnostic
kits is shown in Figure 1. The cross re-
activity was linear. When the LH concentrations obtained on the patient’s
serum samples are plotted on the graph
of the “old” kit vs. the Diagnostic
Products calibrators, the corresponding
I9hCG values approximate the falsely
increased
We thank the National Pituitary Agency
for the lutropin preparations used in this
study. We also thank the Radioiinmunoassay
of Shands Teaching Hospital for
technical
assistance
and Florence
Laboratory
Jordan for preparing
this manuscript.
References
1. Lange, P. H., and Fraley, E. E., Serum
alpha-fetoprotein
and human chorionic go-
-j4(
a
4-
nadotropin
C3
in
the treatment
testicular tumors.
393-399 (1977).
a
C,
x
Q.
IOU
U0
UU
hLH,
mt.
400
QQ
600
units/L
of patients with
Urol. Clin. North Am. 4,
2. Scardine,P. T., Cox,H. D., Waldmann, T.
A., eta!., The value of serum tumor markers
in the staging and prognosis of germ cell tumors of the testis. J. Urol. 118,994(1977).
3. Amoi, S. M., Dissociation of glycoprotein
hormones.
Acta Endocrinol.
70, 29-34
(1972).
Fig. 1. Cross reactivity of /IhCG and LH
with the American Diagnostics Kit
4. Morgan, F. T., and Canfield, IL E., Nature
“old” kit vs Diagnostic Products UI calibrators;
0,
“old” kit vs National Pitultaly Agency (NPA) Nil.
0. “new” 24-h kit vs NPA hLH
(1971).
of the subunits of human chorionic gonadotropin.
Endocrinology
188, 1045-1053
Ketchum’
Noel Maclaren’
Jim Jensen’
Ian Phillips2
Roy Weiner3
Mike Kappy4
results.
Two recommendations can be made
from these observations. First, in case of
bilateral orchiectomy where testosterone replacement is necessary, concentrations of LH should be measured simultaneously with flhCG to ensure LH
suppression. If both 3hCG and LH are
increased, the determinations should be
repeated in one or more weeks, after
testosterone replacement therapy is
begun. Secondly, laboratories routinely
using the I3hCG assay for monitoring
such patients should check their assay
method for cross reactivity with LH,
both during kit evaluation and whenever
changes in antibody preparations are
noted.
their
Catherine
Depts.
of ‘Pathol.,
2Physiol.,
3Med., and 4Pediatrics
Univ.
of Florida
Gainesville,
Coil, of Med.
FL 32610
Address correspondence to Dept. of
Pathol., Box J-275, Univ. of Florida Coil. of
Med., J. Hillis Miller Health
Center,
Gainesville, FL 32610.
Serum Catalase Enzyme Activity in
Acute Pancreatitls
To the Editor:
We have reported the diagnostic importance of determining serum catalase
(EC 1.11.1.6) activity in acute pancreatitis (1). Our simple and economical
procedure (2, 3) enables such determination. In this method unconsumed
hydrogen peroxide substrate is measured with a programmable polarograph
in 30 s, after 60 s of enzymatic reaction.
Using this polarographic method, we
have measured catalase activity in the
serum of patients with both the edematous and the necrotic form of acute
pancreatitis,
and compared this activity
with that of a-amylase
(Phadebas
Amyiase Test, Pharmacia, Sweden) and
lipase (Haury Test Lipase; Dr. Heinz
Haury, Chemische Fabrik, M#{252}nchen,
G.F.R.).
In acute pancreatitis we found highly
increased serum catalase activity [mean
and (SD) 241.3 (171.7) kU/L, n 443] as
compared with normal value [56.7 (21.3)
=
CLINICALCHEMISTRY.Vol. 28, No. 9, 1982
1999
Table 1. Serum Catalase, a-Amylase, and Llpase Enzyme Activities
In Patients with Acute Pancreatitis
Catalas.
Day
Mean
SD
n
Mean
kU/L
a-Amytase
SD
n
Mean
U/L
form (n
Edematous
Llpase
SD
U/L
n
76)
=
275.2
320.6
130.7
148.9
48
2959.6
2582.2
51
305.8
291.4
73
1541.6
1281.6
61
336.7
169.9 21
3
4
243.1
102.8
70
635.5
350.6
59
181.1
63
361.2
139.4
5
133.6
57
269.7
83.5
6
102.1
80.7
36
18
193.1
53
37
27
96.8
76.1
50.1
-
38.7
1
2
179.2
7
486.6
674.0
525.7
1
2
3
66.5
56.5
46.3
31.9
Necrotic form(n
239.9
8 2907.1
307.8 11 1563.8
251.1
10
949.0
204.2
153.8
11
528.3
330.9
6
390.9
280.4
208.8
7
145.9
108.9
68.4
14.1-99.3
4
5
8
127.4
96.2
Normal
10
9
9
9
kU/L, n 1111. In the edematous form
of acute pancreatitis, catalase activity
was less increased [mean (SD) 214.6
(131.7) kUIL, n 369] than in the necrotic form [374.8 (262.7) kU/L, n
=
=
=
74].
In both types of acute pancreatitis the
catalase activity reached its peak later
than that for the a-axnylase activity and
earlier than the peak for lipase activity.
Furthermore, serum catalase activity
returned to the normal range later than
a-amylase activity and earlier than lipase activity (Table 1).
We examined 87 patients with acute
pancreatitis (76 with the edematous
form and 11 with the necrotic form).
a-Amylase was increased in 66 of these
patients (75.8 %), catalase activity in 76
(87.3%), and lipase activity
in 78
(89.6%).
Our results, showing elevated serum
cataiase activity in acute pancreatitis,
confirm the finding of Tsukiyama et al.
(4) and are in agreement with our earlier
paper (1). We found a better correlation
than did GuIzow and M#{246}ller
(5) between
acute pancreatitis and serum catalase
activity, probably because our method
is optimized.
Determination of serum catalase activity, which is highly increased and is
increased for a longer period than
a-amylase, may be useful in the diagnosis of acute pancreatitis.
References
1. M#{233}sz#{225}ros,
I., G#{243}th,
L., and Vattay, Gy.,
The value of serum catalase activity determination in acute pancreatitis. Am J. Dig.
2000
=
118 9
20
44.0
28.1
20.4
11 5
19
16
11
g
11)
668.1
7
228.5
212.7
8
518.0
8
441.3
312.2
9
374.3
9
403.3
282.7
10
Eiectrochromatography
To the Editor:
Gratzer and Beaven, citing the similarity between ion-exchange chromatographic hemoglobin elution patterns
and hemoglobin electrophoretic mobility on citrate agar, concluded that citrate
agar electrophoresis is electrochromatography (1). Barwick and Schneider,
however, studied variant hemoglobins
and pyridoxylated HbA and HbS, which
both then had electrophoretic mobility
similar to that of HbF on citrate agar,
and concluded that anionic binding influences citrate agar mobility (2). Car-
bonic anhydrase B (carbonate dehydratase, BC 4.2.1.1) is an erythrocyte metalloprotein,
which, like HbF, elutes
rapidly from a CM-cellulose column (3).
Hence, carbonic anhydrase B might be
expected to have HbF-like mobility on
264.3
65.3
9
104.0
59.3
9
citrate agar. Therefore, we subjected
212.5
53.1
8
66.5
33.6 8 electrophoretically
prepared human
carbonic anhydrase B (Sigma Chemical
51.6
21.7
9
Co., St. Louis, MO 63178; cat. no. C
70-300
0-45
4396) to citrate agar electrophoresis
_________ (Helena Labs., Beaumont, TX 77704).
The electrophoretic pattern (see Figure
1) indicates that carbonic anhydrase B
2. G#{243}th,
L., and M#{233}sz#{225}ros,
I., Polarographic
and HbF have similar mobility on cidetermination
of serum catalase activity.
Hung. Sci. In8trum. 32, 13-16 (1975).
trate agar electrophoresis.
We believe this result confirms the
3. 06th, L., Determination of serum catalase
enzyme activity with programmable polaroparallel between ion-exchange chrograph. K#{244}rhdz-#{233}s
Orvostechnika.
20, 6-9
matography and citrate agar electro(1982). In Hungarian.
phoresis. Carbonic anhydrase B has low
4. Tsukiyama, Y., Kubota, Y., Misumi, T., et
mobility by starch gel electrophoresis
al., Studies on serum catalase in pancreas (4); therefore, its early elution from
disorders. Med. J. Osaka Univ. 12, 105-135
cation-exchange columns is surprising.
(1961).
A late elution, similar to HbS and HbC,
5. Gulzow, M., and Moller, G., Die Serumwhich are retarded in the column (5),
katalase bei akuter Pankreatitis. Dtsch. Z.
might be expected. The lack of correlaVerdau. Stoffwechselkr.
27, 175-183
tion between electrophoretic mobility
(1967).
and elution rate, however, has long
L#{225}szl#{244}
G6th
267.9
131.7
-
range
Dis. 18, 1035-1041
62.3
-
-
15
Citrate Agar Electrophoresis Is
-
9
9
242.0
154.3
147.7
87.0
9
9
-
Istv#{225}n
M#{233}sz#{225}ros
Hajnalka
N#{233}meth
Depts. of Lab. and Intern.
Med.
Municipal Hospital, Sumeg
Hungary, H-8330
AMERICAN
BOARD OF
CLINICAL CHEMISTRY
in clinical chemistry and
toxicological chemistry for doctoral scientists and physicians.
For Information contact:
Leonard K. Dunikoski, Jr., Ph.D.
Secretary-Treasurer, A.B.C.C.
Perth Amboy GeneralHospital
Certification
Perth
Amboy, NJ 08861
Tel. (201)-442-3700. Ext. 2807
(1973).
CLINICAL CHEMISTRY, Vol. 28, No. 9, 1982
Fig. 1. Results of electrophoresis on citrate agar
The anodeIsattherI#{216},t.
Above we (fromleft) hemogloblns F, A, S, and C. Below Is carbonicanhy&ase B (5 and 0.5 mg/mL). Crowle’s Double Stain
(Polysciences.
Inc., Warrlngton, PA 18976) was used
to stain protein. Notethe single carbonicanhy&ase
B band beneath HbF