1088 There are several possible explanations of this finding but suggest that several C.K. isoenzymes may be hybridised in uraemic medium. BB C.K. was present in serum from patients with renal failure under dialysis,’ 2 of whom had increased we
MB C.K. without myocardial damage. In both, BB activity exceeded MB activity. Serum BB C.K. has been detected in patients from coronary care and emergency unitsin several patients with prolonged atrial fibrillation and congestive heartfailure, and in one with cardiomyopathy.3 It has also been found in malignant hyperpyrexia4and in a patient with metastatic adenocarcinoma of the stomach who had a normal serum-c.K.5 Coolen et al. suggest that the BB isoenzyme is raised after cerebrovascular accidents, kidney transplants, open heart surgery, seizures, and nerve degeneration. MB- C.K. is accepted as a sensitive and specific indicator of myocardial infarction. The significance of BB C.K. is not yet clear, but the radioimmunoassay for MB isoenzyme relies on an antibody to the B subunit which is shared by the BB isoenzyme. MB concentrations by radioimmunoassay may thus be too high in certain patients unless BB contamination can be eliminated. Department of Cardiology, Lady Davis Carmel Hospital, Haifa, Israel
A. MARMOR E. GRENADIER A. PALANT
EXTRA-FETAL ORIGIN OF ALPHAFETOPROTEIN
SIR, The major source of alphafetoprotein (A.F.P.) in the maternal circulation in early pregriancy is thought to be the fetal liver-9 and yolk sac, although there is some evidence for synthesis by placenta8-1Oand kidney.8.9 The demonstration of normal levels for gestational age in the gestation sac fluid of a "blighted ovum" is further evidence for extra-fetal production of A.F.P. in early pregnancy.s Plasma-A.F.P. values in hydatidiform mole are consistently 10w12a further pointer to the major contribution to A.F.P. made by the intact fetus. We have evidence that molar trophoblast can produce significant amounts of A.F.P. despite very low maternal blood levels. The first patient, aged 20, presented with a 12-week history of amenorrhcea and heavy vaginal bleeding for 2 days. General examination was unremarkable, but the uterine size was consistent with 20 weeks’ gestation. On speculum vaginal examination, typical vesicles of hydatidiform mole were observed. The diagnosis was confirmed by ultrasound. The mole was evacuated by suction curettage. Histological appearance of the tissue was consistent with hydatidiform mole, and no fetal elements were seen. The postoperative course was uneventful and the patient is disease-free clinically and biochemically 8 months later. The serum-A.F.p. in an operative blood-sample was 40 jjLg/1. Vesicle fluid obtained by needle aspiration had an A.F.P. concentration of 960 g/1. The second patient, aged 18, was admitted unbooked at 30 weeks of "pregnancy" with a suspected abruptio placentae. Ultrasound examination was consistent with hydatidiform mole. The patient aborted the mole spontaneously on the day of admission, and the remaining tissue was evacuated by curettage. There was no evidence of a fetus, and the microscopic appearance of the tissue was consistent with hydatidiform 1. Roberts, R., Galen, S. Clin. Chem. 1976, 22, 120. 2. Mercer, D. W., ibid. 1977, 23, 611. 3. Mercer, D. W., Varat, M. A. ibid. 1975, 21, 1088. 4. Zsigmand, E. K., Stark Weather, W. H., Duboff, G. S., Flynn, K. A. Anesth. Analg. curr. Res. 1972, 51, 827. 5. Lederer, W. H., Gerstbrein, H. I. Clin. Chem. 1976, 22, 1784. 6. Coolen, R. B., Pragay, D. A., Chilcote, M. E. ibid. 1975, 21, 976. abstr. 7. Gitlin, D., Boesman, M. J. J. clin. Invest. 1967, 46, 1010. 8. Gitlin, D., Pericelli, A., Gitlin, G. M. Cancer Res. 1972, 32, 979. 9. Under, E., Seppala, M. Acta path. micobiol. scand. 1968, 73, 565. 10. van Furth, F., Adinolfi, M. Nature, 1969, 222, 1296. 11. Leek, A. E., Kitau, M. J., Chard, T. Lancet, 1974, ii, 1088. 12. Ishiguro, T. Am. J. Obstet. Gynec. 1975, 121, 539.
mole. The postoperative course was uneventful and the patient is disease-free 4 months later. The serum-A.F.P. level in a pretreatment blood-sample was
MB C.K. without myocardial damage. In both, BB activity exceeded MB activity. Serum BB C.K. has been detected in patients from coronary care and emergency unitsin several patients with prolonged atrial fibrillation and congestive heartfailure, and in one with cardiomyopathy.3 It has also been found in malignant hyperpyrexia4and in a patient with metastatic adenocarcinoma of the stomach who had a normal serum-c.K.5 Coolen et al. suggest that the BB isoenzyme is raised after cerebrovascular accidents, kidney transplants, open heart surgery, seizures, and nerve degeneration. MB- C.K. is accepted as a sensitive and specific indicator of myocardial infarction. The significance of BB C.K. is not yet clear, but the radioimmunoassay for MB isoenzyme relies on an antibody to the B subunit which is shared by the BB isoenzyme. MB concentrations by radioimmunoassay may thus be too high in certain patients unless BB contamination can be eliminated. Department of Cardiology, Lady Davis Carmel Hospital, Haifa, Israel
A. MARMOR E. GRENADIER A. PALANT
EXTRA-FETAL ORIGIN OF ALPHAFETOPROTEIN
SIR, The major source of alphafetoprotein (A.F.P.) in the maternal circulation in early pregriancy is thought to be the fetal liver-9 and yolk sac, although there is some evidence for synthesis by placenta8-1Oand kidney.8.9 The demonstration of normal levels for gestational age in the gestation sac fluid of a "blighted ovum" is further evidence for extra-fetal production of A.F.P. in early pregnancy.s Plasma-A.F.P. values in hydatidiform mole are consistently 10w12a further pointer to the major contribution to A.F.P. made by the intact fetus. We have evidence that molar trophoblast can produce significant amounts of A.F.P. despite very low maternal blood levels. The first patient, aged 20, presented with a 12-week history of amenorrhcea and heavy vaginal bleeding for 2 days. General examination was unremarkable, but the uterine size was consistent with 20 weeks’ gestation. On speculum vaginal examination, typical vesicles of hydatidiform mole were observed. The diagnosis was confirmed by ultrasound. The mole was evacuated by suction curettage. Histological appearance of the tissue was consistent with hydatidiform mole, and no fetal elements were seen. The postoperative course was uneventful and the patient is disease-free clinically and biochemically 8 months later. The serum-A.F.p. in an operative blood-sample was 40 jjLg/1. Vesicle fluid obtained by needle aspiration had an A.F.P. concentration of 960 g/1. The second patient, aged 18, was admitted unbooked at 30 weeks of "pregnancy" with a suspected abruptio placentae. Ultrasound examination was consistent with hydatidiform mole. The patient aborted the mole spontaneously on the day of admission, and the remaining tissue was evacuated by curettage. There was no evidence of a fetus, and the microscopic appearance of the tissue was consistent with hydatidiform 1. Roberts, R., Galen, S. Clin. Chem. 1976, 22, 120. 2. Mercer, D. W., ibid. 1977, 23, 611. 3. Mercer, D. W., Varat, M. A. ibid. 1975, 21, 1088. 4. Zsigmand, E. K., Stark Weather, W. H., Duboff, G. S., Flynn, K. A. Anesth. Analg. curr. Res. 1972, 51, 827. 5. Lederer, W. H., Gerstbrein, H. I. Clin. Chem. 1976, 22, 1784. 6. Coolen, R. B., Pragay, D. A., Chilcote, M. E. ibid. 1975, 21, 976. abstr. 7. Gitlin, D., Boesman, M. J. J. clin. Invest. 1967, 46, 1010. 8. Gitlin, D., Pericelli, A., Gitlin, G. M. Cancer Res. 1972, 32, 979. 9. Under, E., Seppala, M. Acta path. micobiol. scand. 1968, 73, 565. 10. van Furth, F., Adinolfi, M. Nature, 1969, 222, 1296. 11. Leek, A. E., Kitau, M. J., Chard, T. Lancet, 1974, ii, 1088. 12. Ishiguro, T. Am. J. Obstet. Gynec. 1975, 121, 539.
mole. The postoperative course was uneventful and the patient is disease-free 4 months later. The serum-A.F.P. level in a pretreatment blood-sample was
