- Email: [email protected]
EPIDEMICS OF ANENCEPHALY AND SPINA BIFIDA
1303 imbalance such as a partial trisomy, this has, nevertheless, to be kept in mind. Heart and palate malformations are seen in the trisomy Di syndrome; however, other features which
"CO-VITAMIN-B12
ABSORPTION STUDIES
are frequently seen in that syndrome-namely, polydactyly, genitourinary malformations, malformations of the abdominal wall or cavity, malformations of the external ears, and cleft lip-were not observed in either fetus. Thus we are possibly dealing with an autosomal recessive gene, which
in the homozygous state results in ventricular septal defect, arteriosus, cleft palate, and intrauterine death. If this interpretation is correct, the recurrence risk for these parents may well be as high as 25% with each pregnancy. There are two reasons for reporting these cases. One is to draw attention to a possible new recessive syndrome, and the second is to point out that much valuable information is frequently not utilised in the study of stillbirths. These infants should be studied by all available techniquesnamely, necropsy, surface examination including intraoral structures, and dermatoglyphic, photographic, radiographic, virological, and chromosomal methods. Unfortunately, maceration may prevent a number of these being done, such as was the case in this report. However, there have been other instances where successful chromosome culture was obtained if the interval between the intrauterine death and subsequent delivery was relatively short. truncus
These investigations were supported by the Medical Research Council of Canada, grant no. MA-3415, and by a grant from the Children’s Hospital, 250 West 59th Avenue, Vancouver. We would like to acknowledge the help and cooperation of the
referring physician and of Dr. Betty J. Poland and her staff, of the embryology section of the division of medical genetics. Division of Medical Genetics, Department of Pædiatrics, University of British Columbia, Vancouver, B.C., Canada.
R. B. LOWRY MILLER.
J. R.
VITAMIN-B12 ABSORPTION AND THE ZOLLINGER-ELLISON SYNDROME SiR,-We have reported that, in vitro, the binding of vitamin Bis by human gastric juice intrinsic factor is pHdependent.1 Maximum binding occurs between pH 6-5 and 10. Outside this pH range the binding decreases, and at pH below 2 or above 12.2 this drops sharply to about 10-15% of the maximum. These pH effects may be relevant to certain abnormalities of vitamin-B12 absorption in patients with pancreatic insufficiency and a low intestinal pH 2,3 and in a case of Zollinger-Ellison syndrome.4 Apparently, vitamin-B12 malabsorption in these patients was not due to the lack of gastric-juice intrinsic factor but was possibly a result of the low pH (? inadequate binding between vitamin B12 and intrinsic factor) in the smallintestine, where vitamin-B12 absorption takes place. We report here 58Co-vitamin-B12 absorption studies on a patient with Zollinger-Ellison syndrome. The patient (male, 53 years of age) had proven Zollinger-Ellison syndrome, with a basal acid secretion of 70-100 meq. per hour (normal less than 3 meq. per hour), serum-gastrin level of 0-98 ng. per ml. (normal less than 0.4 ng. per ml.), faccalfat excretion 65 g. daily, and a normal xylose-absorption test. A small-bowel biopsy specimen showed partial villous atrophy. His serum-vitamin B12 was 460 pg. per ml. (normal 150-950 pg. per ml.), serum-folic-acid was 4’3 ng. per ml. (normal 4-12 ng. per ml.), gastric-juice 1.
Shum, H. Y., O’Neill, B. J., Streeter, A.
M. J. clin. Path. (in the press). 2. Veeger, W., Hellemans, N., Neiweg, H. O. New Engl. J. Med. 1962, 267, 1341. 3. Le Bauer, E., Smith, K., Greenberger, N. J. Archs intern. Med. 1968, 122, 423. 4. Shimoda, S. S., Saunders, D. R., Rubin, C. E. Gastroenterology, 1967, 52, 1119.
* 1st day=61·2%; 2nd day =11-4%. t Woodliff, H. J., Armstrong, B. J. Med. J. Aust. 1966, i, 1023. t This range was obtained by performing the fascal-excretion test on two normal subjects on 4 separate occasions-the stool collection was extended to 5-7 days until no radioactivity was detected.
intrinsic factor was 35 ng. units per ml. (mean of two separate determinations, normal mean value about 36 ng. units per ml.), and there was no intrinsic-factor-blocking antibody in his serum.
Vitamin-B12-absorption tests were performed using 58Co-vitamin-B12 (this was used instead of 5’Co-vitaminB12 because this patient was previously given some 75Seselenomethionine which could interfere with 57CO counting but not with 58Co counting). The Schilling test with 8-hour plasma-level test was carried out on two occasions. On a third occasion, in addition to the Schilling test and 8-hour plasma-level test, a two-day fxcal-excretion test was also performed. The results of these tests are summarised in the accompanying table. The first two Schilling tests (urinary excretion) were normal, but both the plasma-level tests were slightly abnormal. We could not offer a satisfactory explanation for this discrepancy, although such results might suggest there was a decreased rate of 58COvitamin-B12 absorption into the bloodstream. Results of study 3, however, are in good agreement. Both the Schilling test and the plasma-level test were low-but were not typical of results seen in pernicious anaemia. The fscal excretion was high compared with two normal subjects and reported normal figures. Since only a two-day stool collection
carried out, the total amount of 58COabsorbed could have exceeded 75% of the oral dose if the stool collection had been extended. Although the overall results of these studies are not conclusive, study 3 tends to suggest a certain degree of vitamin-Bi2 malabsorption in this patient. This could be attributed to the adverse pH effect on the binding of vitamin-B12 by gastric-juice intrinsic factor, but not to an actual lack of gastric-juice intrinsic factor. To our knowledge, this is only the second report relating vitamin-B12 malabsorption to the Zollinger-Ellison syndrome. was
vitamin-B12
not
Division of Hæmatology, Repatriation General Hospital, Concord, N.S.W. 2139, Australia.
HING-YAN SHUM BARRY J. O’NEILL ARTHUR M. STREETER.
EPIDEMICS OF ANENCEPHALY AND SPINA BIFIDA
SIR,-May I make
a
small correction
to your
"
editorial "
(April 13, p. 689) ? You say that a pseudoepidemic of hydrocephalus which I reportedwas shown by Lorber2 artefact due
to a change of classification at the General’s In fact, reference to Lorber’s office. Registrar paper shows that the classification change to which he referred was in 1963, whereas the epidemic I reported occurred in 1940-41. However, as mentioned in the earlier paper, the coding instructions used at the Registrar General’s office were checked by Dr. M. Heasman in order to ensure that a change in the rules of assignment
to
1. 2.
be
an
Carter, M. P. Devl. Med. Chld Neurol. 1965, 7, Lorber, J. Med. Offr, 1968, 69, 213.
61.
1304 which was made in 1940 was not leading to an artefactual peak in the hydrocephalus infant deaths. Dr. Heasman could find no evidence that this was so; the peak seemed to be a genuine phenomenon. It is of interest that there was another small peak of infant deaths due to spina bifida in 1942. M. P. CARTER. Lowestoft.
POLYVINYLPYRROLIDONE SOLUTIONS USED IN PLASMA EXPANDERS: POTENTIAL CARCINOGENS ? SIR,-Solutions of polyvinylpyrrolidone (povidone, P.v.p.) have been used extensively in the past, especially in continental Europe, as plasma expanders. Concern about the possible connection between P.v.p. and cancer has led to greatly reduced use in clinical practice.1 Reports have also appeared on the induction of liver lesions in patients treated with P.v.P. samples.2 Although P.v.p. is essentially inert in a direct chemical sense, the adverse biological effects of P.v.p. have been associated with the higher-molecular-weight fractions always present in samples used in plasma expanders. In the course of a study on the cryoprotective action of P.v.p. it was noted that the molecular-weight spread of the commercially available samples was very much greater than the manufacturers claim.’Plasdone C’ (produced in the U.S.A. by General Aniline and Film Corporation of New York) is claimed to have an average molecular weight of 40,000 daltons with a spread of 20,000 to 80,000 daltons. The trouble, then, with P.V.P. samples of this composition used in plasma expanders rests with that fraction uncleared by the kidney. Experiments with three pure samples of P.v.p. supplied by the General Aniline Company have indicated that molecular-weight distribution extends from 1000 daltons to values greater than 150,000 daltons. The evidence for this statement is unequivocal and is based on gel-exclusion chromatography onSephadex’ columns (both G100 and G200). Three different P.v.p. samples (K30, K32-6, and K36) were measured by ultraviolet spectroscopy at 200 m;jt or 14C content (for radioactive Results of analysis after chromatographic samples). of separation plasdone C, one of the most commonly used 1. 2.
Hueper, W. C. Proc. Am. Ass. Cancer Res. 1956, 2, 120. Gall, E. A. Abstr. Wld Med. 1954, 15, 463.
Fig. 2-Behaviour of plasdone C (P.V.P.) in distilled water on a column of sephadex G100. Elution pattern of bovine serum-albumin included for com-
parison.
plasma expanders, are shown in figs. 1 and 2. For comparison, the behaviour of bovine serum-albumin on these columns is shown. It is quite obvious that injection of P.v.p., or administration by other routes (P.v.p. solutions are used in a variety of proprietary preparations to delay liberation of active drugs such as hormones and antibiotics), would result in a substantial retention within the lysosomes of the cells of the reticuloendothelial system, and thus might well be implicated or associated with cancer induction.3 This information may be useful to those investigators who have access to clinical histories of those many thousands of patients treated with plasma expanders containing P.v.p. during the 1939-45 war and the fifteen or so years after it. Department of Biological Sciences, University of Victoria, Victoria, B.C., M. J. ASHWOOD-SMITH. Canada. SEX-LINKED ICHTHYOSIS IN XO GONADAL DYSGENESIS
SiR,ŇIn 1956, Polani et al. demonstrated an increased incidence of congenital red-green colour blindness-a common sex-linked recessive disorder-in a patient with chromosomal gonadal dysgenesis. Subsequently, hxmophilia A was reported in two girls with sex-chromosome abnormalities: one was sex-chromatin negative,5 and the other had 46,XX, 45,X mosaicism.6 The following case illustrates another X-linked recessive disorder, ichthyosis, in a girl with XO gonadal dysgenesis. A 16-year-old girl was seen for evaluation of short stature, absent secondary sex characteristics, and primary amenorrhcea. She had a history of lymphcedema of the feet in infancy. Chronic dry skin, first called to medical attention when she was 14 years old, was diagnosed as ichthyosis. Studies revealed a chromatin-negative buccal smear and 45,X chromosomes in peripheral-blood cells. Fig. I-Behaviour of plasdone C (P.V.P.) in phosphate buffer (pH 70; 0’07M) on a column of sephadex G200. Elution pattern of bovine serum-albumin included for com-
parison (molecular weight 67,000 daltons).
3. 4. 5.
6.
Allison, A. C. Europ. J. Cancer, 1968, 3, 481. Polani, P. E., Lessof, M. H., Bishop, P. M. F. Lancet, 1956, ii, 118. Nilsson, I. M., Bergman, S., Reitalu, J., Waldenström, J. ibid. 1959, ii, 264. Gilchrist, G. S., Hammond, D., Melnyh, J. New Engl. J. Med. 1965, 273, 1402.
"CO-VITAMIN-B12
ABSORPTION STUDIES
are frequently seen in that syndrome-namely, polydactyly, genitourinary malformations, malformations of the abdominal wall or cavity, malformations of the external ears, and cleft lip-were not observed in either fetus. Thus we are possibly dealing with an autosomal recessive gene, which
in the homozygous state results in ventricular septal defect, arteriosus, cleft palate, and intrauterine death. If this interpretation is correct, the recurrence risk for these parents may well be as high as 25% with each pregnancy. There are two reasons for reporting these cases. One is to draw attention to a possible new recessive syndrome, and the second is to point out that much valuable information is frequently not utilised in the study of stillbirths. These infants should be studied by all available techniquesnamely, necropsy, surface examination including intraoral structures, and dermatoglyphic, photographic, radiographic, virological, and chromosomal methods. Unfortunately, maceration may prevent a number of these being done, such as was the case in this report. However, there have been other instances where successful chromosome culture was obtained if the interval between the intrauterine death and subsequent delivery was relatively short. truncus
These investigations were supported by the Medical Research Council of Canada, grant no. MA-3415, and by a grant from the Children’s Hospital, 250 West 59th Avenue, Vancouver. We would like to acknowledge the help and cooperation of the
referring physician and of Dr. Betty J. Poland and her staff, of the embryology section of the division of medical genetics. Division of Medical Genetics, Department of Pædiatrics, University of British Columbia, Vancouver, B.C., Canada.
R. B. LOWRY MILLER.
J. R.
VITAMIN-B12 ABSORPTION AND THE ZOLLINGER-ELLISON SYNDROME SiR,-We have reported that, in vitro, the binding of vitamin Bis by human gastric juice intrinsic factor is pHdependent.1 Maximum binding occurs between pH 6-5 and 10. Outside this pH range the binding decreases, and at pH below 2 or above 12.2 this drops sharply to about 10-15% of the maximum. These pH effects may be relevant to certain abnormalities of vitamin-B12 absorption in patients with pancreatic insufficiency and a low intestinal pH 2,3 and in a case of Zollinger-Ellison syndrome.4 Apparently, vitamin-B12 malabsorption in these patients was not due to the lack of gastric-juice intrinsic factor but was possibly a result of the low pH (? inadequate binding between vitamin B12 and intrinsic factor) in the smallintestine, where vitamin-B12 absorption takes place. We report here 58Co-vitamin-B12 absorption studies on a patient with Zollinger-Ellison syndrome. The patient (male, 53 years of age) had proven Zollinger-Ellison syndrome, with a basal acid secretion of 70-100 meq. per hour (normal less than 3 meq. per hour), serum-gastrin level of 0-98 ng. per ml. (normal less than 0.4 ng. per ml.), faccalfat excretion 65 g. daily, and a normal xylose-absorption test. A small-bowel biopsy specimen showed partial villous atrophy. His serum-vitamin B12 was 460 pg. per ml. (normal 150-950 pg. per ml.), serum-folic-acid was 4’3 ng. per ml. (normal 4-12 ng. per ml.), gastric-juice 1.
Shum, H. Y., O’Neill, B. J., Streeter, A.
M. J. clin. Path. (in the press). 2. Veeger, W., Hellemans, N., Neiweg, H. O. New Engl. J. Med. 1962, 267, 1341. 3. Le Bauer, E., Smith, K., Greenberger, N. J. Archs intern. Med. 1968, 122, 423. 4. Shimoda, S. S., Saunders, D. R., Rubin, C. E. Gastroenterology, 1967, 52, 1119.
* 1st day=61·2%; 2nd day =11-4%. t Woodliff, H. J., Armstrong, B. J. Med. J. Aust. 1966, i, 1023. t This range was obtained by performing the fascal-excretion test on two normal subjects on 4 separate occasions-the stool collection was extended to 5-7 days until no radioactivity was detected.
intrinsic factor was 35 ng. units per ml. (mean of two separate determinations, normal mean value about 36 ng. units per ml.), and there was no intrinsic-factor-blocking antibody in his serum.
Vitamin-B12-absorption tests were performed using 58Co-vitamin-B12 (this was used instead of 5’Co-vitaminB12 because this patient was previously given some 75Seselenomethionine which could interfere with 57CO counting but not with 58Co counting). The Schilling test with 8-hour plasma-level test was carried out on two occasions. On a third occasion, in addition to the Schilling test and 8-hour plasma-level test, a two-day fxcal-excretion test was also performed. The results of these tests are summarised in the accompanying table. The first two Schilling tests (urinary excretion) were normal, but both the plasma-level tests were slightly abnormal. We could not offer a satisfactory explanation for this discrepancy, although such results might suggest there was a decreased rate of 58COvitamin-B12 absorption into the bloodstream. Results of study 3, however, are in good agreement. Both the Schilling test and the plasma-level test were low-but were not typical of results seen in pernicious anaemia. The fscal excretion was high compared with two normal subjects and reported normal figures. Since only a two-day stool collection
carried out, the total amount of 58COabsorbed could have exceeded 75% of the oral dose if the stool collection had been extended. Although the overall results of these studies are not conclusive, study 3 tends to suggest a certain degree of vitamin-Bi2 malabsorption in this patient. This could be attributed to the adverse pH effect on the binding of vitamin-B12 by gastric-juice intrinsic factor, but not to an actual lack of gastric-juice intrinsic factor. To our knowledge, this is only the second report relating vitamin-B12 malabsorption to the Zollinger-Ellison syndrome. was
vitamin-B12
not
Division of Hæmatology, Repatriation General Hospital, Concord, N.S.W. 2139, Australia.
HING-YAN SHUM BARRY J. O’NEILL ARTHUR M. STREETER.
EPIDEMICS OF ANENCEPHALY AND SPINA BIFIDA
SIR,-May I make
a
small correction
to your
"
editorial "
(April 13, p. 689) ? You say that a pseudoepidemic of hydrocephalus which I reportedwas shown by Lorber2 artefact due
to a change of classification at the General’s In fact, reference to Lorber’s office. Registrar paper shows that the classification change to which he referred was in 1963, whereas the epidemic I reported occurred in 1940-41. However, as mentioned in the earlier paper, the coding instructions used at the Registrar General’s office were checked by Dr. M. Heasman in order to ensure that a change in the rules of assignment
to
1. 2.
be
an
Carter, M. P. Devl. Med. Chld Neurol. 1965, 7, Lorber, J. Med. Offr, 1968, 69, 213.
61.
1304 which was made in 1940 was not leading to an artefactual peak in the hydrocephalus infant deaths. Dr. Heasman could find no evidence that this was so; the peak seemed to be a genuine phenomenon. It is of interest that there was another small peak of infant deaths due to spina bifida in 1942. M. P. CARTER. Lowestoft.
POLYVINYLPYRROLIDONE SOLUTIONS USED IN PLASMA EXPANDERS: POTENTIAL CARCINOGENS ? SIR,-Solutions of polyvinylpyrrolidone (povidone, P.v.p.) have been used extensively in the past, especially in continental Europe, as plasma expanders. Concern about the possible connection between P.v.p. and cancer has led to greatly reduced use in clinical practice.1 Reports have also appeared on the induction of liver lesions in patients treated with P.v.P. samples.2 Although P.v.p. is essentially inert in a direct chemical sense, the adverse biological effects of P.v.p. have been associated with the higher-molecular-weight fractions always present in samples used in plasma expanders. In the course of a study on the cryoprotective action of P.v.p. it was noted that the molecular-weight spread of the commercially available samples was very much greater than the manufacturers claim.’Plasdone C’ (produced in the U.S.A. by General Aniline and Film Corporation of New York) is claimed to have an average molecular weight of 40,000 daltons with a spread of 20,000 to 80,000 daltons. The trouble, then, with P.V.P. samples of this composition used in plasma expanders rests with that fraction uncleared by the kidney. Experiments with three pure samples of P.v.p. supplied by the General Aniline Company have indicated that molecular-weight distribution extends from 1000 daltons to values greater than 150,000 daltons. The evidence for this statement is unequivocal and is based on gel-exclusion chromatography onSephadex’ columns (both G100 and G200). Three different P.v.p. samples (K30, K32-6, and K36) were measured by ultraviolet spectroscopy at 200 m;jt or 14C content (for radioactive Results of analysis after chromatographic samples). of separation plasdone C, one of the most commonly used 1. 2.
Hueper, W. C. Proc. Am. Ass. Cancer Res. 1956, 2, 120. Gall, E. A. Abstr. Wld Med. 1954, 15, 463.
Fig. 2-Behaviour of plasdone C (P.V.P.) in distilled water on a column of sephadex G100. Elution pattern of bovine serum-albumin included for com-
parison.
plasma expanders, are shown in figs. 1 and 2. For comparison, the behaviour of bovine serum-albumin on these columns is shown. It is quite obvious that injection of P.v.p., or administration by other routes (P.v.p. solutions are used in a variety of proprietary preparations to delay liberation of active drugs such as hormones and antibiotics), would result in a substantial retention within the lysosomes of the cells of the reticuloendothelial system, and thus might well be implicated or associated with cancer induction.3 This information may be useful to those investigators who have access to clinical histories of those many thousands of patients treated with plasma expanders containing P.v.p. during the 1939-45 war and the fifteen or so years after it. Department of Biological Sciences, University of Victoria, Victoria, B.C., M. J. ASHWOOD-SMITH. Canada. SEX-LINKED ICHTHYOSIS IN XO GONADAL DYSGENESIS
SiR,ŇIn 1956, Polani et al. demonstrated an increased incidence of congenital red-green colour blindness-a common sex-linked recessive disorder-in a patient with chromosomal gonadal dysgenesis. Subsequently, hxmophilia A was reported in two girls with sex-chromosome abnormalities: one was sex-chromatin negative,5 and the other had 46,XX, 45,X mosaicism.6 The following case illustrates another X-linked recessive disorder, ichthyosis, in a girl with XO gonadal dysgenesis. A 16-year-old girl was seen for evaluation of short stature, absent secondary sex characteristics, and primary amenorrhcea. She had a history of lymphcedema of the feet in infancy. Chronic dry skin, first called to medical attention when she was 14 years old, was diagnosed as ichthyosis. Studies revealed a chromatin-negative buccal smear and 45,X chromosomes in peripheral-blood cells. Fig. I-Behaviour of plasdone C (P.V.P.) in phosphate buffer (pH 70; 0’07M) on a column of sephadex G200. Elution pattern of bovine serum-albumin included for com-
parison (molecular weight 67,000 daltons).
3. 4. 5.
6.
Allison, A. C. Europ. J. Cancer, 1968, 3, 481. Polani, P. E., Lessof, M. H., Bishop, P. M. F. Lancet, 1956, ii, 118. Nilsson, I. M., Bergman, S., Reitalu, J., Waldenström, J. ibid. 1959, ii, 264. Gilchrist, G. S., Hammond, D., Melnyh, J. New Engl. J. Med. 1965, 273, 1402.