983
ground upon which hypothesis are based, hypothesis can explain
discussions of the methylfolate-trap and lessen the probability that this the megaloblastic anaemias.
Biochemistry Department, Institute of Psychiatry, De Crespigny Park, Denmark Hill, London SE5 8AF.
MICHAEL R. BOARDER
ESSENTIAL-FATTY-ACID METABOLISM IN CYSTIC FIBROSIS
SIR,-Mr Rivers and Mr Hassam (Oct. 4, p. 642) have postulated that patients with cystic fibrosis lack fatty-acid-desaturating-enzyme activity. Their conclusion rest basically on two pieces of information provided by data in the literature: linoleic acid (18:2) and arachidonic acid (20:4) levels were low, and no worker had reported 5, 8, ll-eicosatrienoic acid (20:3 w-9) in the sera studied. In view of this we thought it would be of interest to report our results. 6 patients with proven cystic fibrosis and a wide variety of Schwachman clinical scores were studied, and the controls were 10 healthy children undergoing minor elective surgical procedures. About 0.5 ml clotted blood was used. Fatty-acid analyses of the total phospholipids were performed on a 165 cm x 0.65 cm column of 5% polyethylene glycol succinate. Molar correction factors’ were obtained using standard weighed mixtures, but the factor for 20:3 w-9 was assumed to SERUM-FATTY-ACIDS IN CYSTIC FIBROSIS
Our results suggest that there is
no
intrinsic defect of the
desaturating system in cystic fibrosis and that the pattern of essential-fatty-acid deficiency is entirely similar to that found in dietary deficiency of essential fatty acids.4-8 A further significant finding8 is the oecurance of 20:3 w-9 in apparently healthy children, particularly the very young. This is probably diet-related9 and emphasises the young child’s very large requirement for essential fatty acids for membrane synthesis. The need for adequate polyunsaturated fatty acids in childhood cannot be overstated, whether they be for normal membrane synthesis or lowering of serum-lipids,lo giving possible protection against cardiovascular disease." 12 We are grateful to Prof.C. M. Anderson, whose patients with cystic fibrosis we studied, and to Prof. K. W. Walton for his interest. One of us (R.W.) is the holder of a fellowship funded by the Medical Research Council, and the British Heart Foundation provided the gas-
chromatography equipment. Department of Experimental Pathology, University of Birmingham.
RODNEY WATTS STELLA TAYLOR
Institute of Child Health
University of Birmingham, Francis Road, Birmingham,
RAY POSTUMA CHRISTINE A. SMALLEY.
16.
FIREWORKS
SIR,-A usually scrupulous regard for facts ensures considerable authority for any editorial in The Lancet. The normal critical standards fell sadly in your article on fireworks, which would appear to have been based on a series of unproven (and indeed unprovable) assertions from the National Campaign for Firework Reform, mixed up with a sprinkling of accurate figures presented in such a way as to obscure any reasonable -
perspective. How, for example,
can it truthfully be said that there are firework accidents in Britain than in any other country in the world? Our Government publishes official figures, but there are none in such relevant countries as France, Belgium, Holland, Norway, Denmark, Eire, or Spain; and there are only partial statistics from some hospitals in Sweden. In the U.S.A., where there is a serious problem of illicit trade between those states which allow fireworks and those which do not, the Consumer Product Safety Commission estimates a yearly total of 6600 accidents-a figure which is both absolutely and proportionately higher than ours. And if British official figures are quoted, they ought at least to be quoted accurately. The article refers to 1861 children injured last year. In fact there were only 927 casulaties, including adults and children. It speaks of 257 serious injuries to children. In fact there were 205 such injuries all told, and only about 158 of these were to children. Errors of fact on this scale cannot be merely laughed off with the glib assertion that even one accident is too many. Accidents occur in many different circumstances-in the home, on the road, at work, in the football stands-and in many instances they are severe and, all too sadly, preventable. But curiously, they do not attract in certain quarters the same degree of emotionally hostile concentration as firework injuries, even though the latter pale almost into statistical insignificance beside their huge totals. There is, furthermore, a
more
be the same as for the w-6 isomer. Fatty acids of 14 to 20 carbon atoms were analysed. The results (see table) show that for children with cystic fibrosis there are not only decreased proportions of essential fatty acids but that 20:3 (0)-9 is found in all cases. The results show that 20:3 w-9 can also occur as significant proportions in very young children. We thus seem to be at variance with previously published work, but a closer study of the papers cited by Rivers and Hassam has revealed the following. In only one paper2 was there any attempt to find 20:3 w-9 in the sera of patients with cystic fibrosis, and there are reasons why those workers found none. 20:3 w-9 is preferentially retained in the phospholipids (lecithin),3 and thus any analysis which deals with total-serumlipids contains a considerable dilution factor. All of the G.L.C. columns with 15-20% stationary phase give long retentiontimes and consequently relatively low broad peaks for carbon-20 fatty acids. However, these technical details apart, all the patients investigated by Bennett and Medwadowski had very high levels of 18:2 and 20:4 when compared with "normal" populations. Furthermore, their youngest patients were 3 years old, but our results indicate a general decrease in 20:3 ÚJ-9with age. 1
Smith, S., Watts, R., Dils, R. J. Lipid Res. 1968, 9, 52. 2. Bennett, M. J., Medwadowski, B. F. Am. J. clin. Nutr. 1957, 20, 415. 3. Aaes-Jorgensen, E. Physiol. Res. 1961, 41, 1.
Collins, F. D., Sinclair, A. J., Royle, J. P., Coats, D. A., Maynard, A. T., Leonard, R. F. Nutr. Metab. 1971, 13, 150. 5. Press, M., Kikuchi, H., Shimoyama, T., Thompson, G. R. Br. med. J. 1974, ii, 247. 6. McEvoy, F. A. Lancet, 1975, ii, 236. 7. Love, W. C., Cashell, A., Reynolds, M., Callaghan, N. Br. med. J. 1974, iii,
4.
18.
Paulsrud, J. R., Pensler, L., Whitten, C. F., Stewart, S., Holman, R. T. Am.J. clin. Nutr. 1972, 25, 897. 9. Woodruff, C. W., Bailey, M. C., Davis, J. T., Rogers, N., Coniglio, J. G. ibid. 1964, 14, 83. 10. Glueck, C. J., Tsang, R., Balistreri, W., Fallat, R. Metabolism, 1972, 21, 8.
1181. 11. McBean, L. D., Speckmann, E. W. Pediat. Res. 1974, 8, 837. 12. Kingsbury, K. J., Brett, C., Stovold, R., Chapman, A., Anderson, gan, D. M. Postgrad. med.J. 1974, 50, 425.
J.,
Mor-
ground upon which hypothesis are based, hypothesis can explain
discussions of the methylfolate-trap and lessen the probability that this the megaloblastic anaemias.
Biochemistry Department, Institute of Psychiatry, De Crespigny Park, Denmark Hill, London SE5 8AF.
MICHAEL R. BOARDER
ESSENTIAL-FATTY-ACID METABOLISM IN CYSTIC FIBROSIS
SIR,-Mr Rivers and Mr Hassam (Oct. 4, p. 642) have postulated that patients with cystic fibrosis lack fatty-acid-desaturating-enzyme activity. Their conclusion rest basically on two pieces of information provided by data in the literature: linoleic acid (18:2) and arachidonic acid (20:4) levels were low, and no worker had reported 5, 8, ll-eicosatrienoic acid (20:3 w-9) in the sera studied. In view of this we thought it would be of interest to report our results. 6 patients with proven cystic fibrosis and a wide variety of Schwachman clinical scores were studied, and the controls were 10 healthy children undergoing minor elective surgical procedures. About 0.5 ml clotted blood was used. Fatty-acid analyses of the total phospholipids were performed on a 165 cm x 0.65 cm column of 5% polyethylene glycol succinate. Molar correction factors’ were obtained using standard weighed mixtures, but the factor for 20:3 w-9 was assumed to SERUM-FATTY-ACIDS IN CYSTIC FIBROSIS
Our results suggest that there is
no
intrinsic defect of the
desaturating system in cystic fibrosis and that the pattern of essential-fatty-acid deficiency is entirely similar to that found in dietary deficiency of essential fatty acids.4-8 A further significant finding8 is the oecurance of 20:3 w-9 in apparently healthy children, particularly the very young. This is probably diet-related9 and emphasises the young child’s very large requirement for essential fatty acids for membrane synthesis. The need for adequate polyunsaturated fatty acids in childhood cannot be overstated, whether they be for normal membrane synthesis or lowering of serum-lipids,lo giving possible protection against cardiovascular disease." 12 We are grateful to Prof.C. M. Anderson, whose patients with cystic fibrosis we studied, and to Prof. K. W. Walton for his interest. One of us (R.W.) is the holder of a fellowship funded by the Medical Research Council, and the British Heart Foundation provided the gas-
chromatography equipment. Department of Experimental Pathology, University of Birmingham.
RODNEY WATTS STELLA TAYLOR
Institute of Child Health
University of Birmingham, Francis Road, Birmingham,
RAY POSTUMA CHRISTINE A. SMALLEY.
16.
FIREWORKS
SIR,-A usually scrupulous regard for facts ensures considerable authority for any editorial in The Lancet. The normal critical standards fell sadly in your article on fireworks, which would appear to have been based on a series of unproven (and indeed unprovable) assertions from the National Campaign for Firework Reform, mixed up with a sprinkling of accurate figures presented in such a way as to obscure any reasonable -
perspective. How, for example,
can it truthfully be said that there are firework accidents in Britain than in any other country in the world? Our Government publishes official figures, but there are none in such relevant countries as France, Belgium, Holland, Norway, Denmark, Eire, or Spain; and there are only partial statistics from some hospitals in Sweden. In the U.S.A., where there is a serious problem of illicit trade between those states which allow fireworks and those which do not, the Consumer Product Safety Commission estimates a yearly total of 6600 accidents-a figure which is both absolutely and proportionately higher than ours. And if British official figures are quoted, they ought at least to be quoted accurately. The article refers to 1861 children injured last year. In fact there were only 927 casulaties, including adults and children. It speaks of 257 serious injuries to children. In fact there were 205 such injuries all told, and only about 158 of these were to children. Errors of fact on this scale cannot be merely laughed off with the glib assertion that even one accident is too many. Accidents occur in many different circumstances-in the home, on the road, at work, in the football stands-and in many instances they are severe and, all too sadly, preventable. But curiously, they do not attract in certain quarters the same degree of emotionally hostile concentration as firework injuries, even though the latter pale almost into statistical insignificance beside their huge totals. There is, furthermore, a
more
be the same as for the w-6 isomer. Fatty acids of 14 to 20 carbon atoms were analysed. The results (see table) show that for children with cystic fibrosis there are not only decreased proportions of essential fatty acids but that 20:3 (0)-9 is found in all cases. The results show that 20:3 w-9 can also occur as significant proportions in very young children. We thus seem to be at variance with previously published work, but a closer study of the papers cited by Rivers and Hassam has revealed the following. In only one paper2 was there any attempt to find 20:3 w-9 in the sera of patients with cystic fibrosis, and there are reasons why those workers found none. 20:3 w-9 is preferentially retained in the phospholipids (lecithin),3 and thus any analysis which deals with total-serumlipids contains a considerable dilution factor. All of the G.L.C. columns with 15-20% stationary phase give long retentiontimes and consequently relatively low broad peaks for carbon-20 fatty acids. However, these technical details apart, all the patients investigated by Bennett and Medwadowski had very high levels of 18:2 and 20:4 when compared with "normal" populations. Furthermore, their youngest patients were 3 years old, but our results indicate a general decrease in 20:3 ÚJ-9with age. 1
Smith, S., Watts, R., Dils, R. J. Lipid Res. 1968, 9, 52. 2. Bennett, M. J., Medwadowski, B. F. Am. J. clin. Nutr. 1957, 20, 415. 3. Aaes-Jorgensen, E. Physiol. Res. 1961, 41, 1.
Collins, F. D., Sinclair, A. J., Royle, J. P., Coats, D. A., Maynard, A. T., Leonard, R. F. Nutr. Metab. 1971, 13, 150. 5. Press, M., Kikuchi, H., Shimoyama, T., Thompson, G. R. Br. med. J. 1974, ii, 247. 6. McEvoy, F. A. Lancet, 1975, ii, 236. 7. Love, W. C., Cashell, A., Reynolds, M., Callaghan, N. Br. med. J. 1974, iii,
4.
18.
Paulsrud, J. R., Pensler, L., Whitten, C. F., Stewart, S., Holman, R. T. Am.J. clin. Nutr. 1972, 25, 897. 9. Woodruff, C. W., Bailey, M. C., Davis, J. T., Rogers, N., Coniglio, J. G. ibid. 1964, 14, 83. 10. Glueck, C. J., Tsang, R., Balistreri, W., Fallat, R. Metabolism, 1972, 21, 8.
1181. 11. McBean, L. D., Speckmann, E. W. Pediat. Res. 1974, 8, 837. 12. Kingsbury, K. J., Brett, C., Stovold, R., Chapman, A., Anderson, gan, D. M. Postgrad. med.J. 1974, 50, 425.
J.,
Mor-
