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CYSTIC FIBROSIS AND PSEUDOMONAS INFECTION
794 SUGAR AND OBESITY
CYSTIC FIBROSIS AND PSEUDOMONAS INFECTION
SIR,-Professor Vlitos (Sept 17, p 688) says that I claim that "the obese are obese because they eat ’too many sweets". This is a considerable distortion of my letter of Aug 27 (p 517), in which I give, among the examples of the food I indict, whisky, beer, biscuits and cakes-the foods and drinks that people take to give pleasure rather than to alleviate hunger.
SIR,-I wish to comment on your editorial of July 30 (p 257). An unfounded belief has grown up that the mucoid substance produced by strains of Pseudomonas aeruginosa from cystic fibrosis patients does not generate an antibody response. It has recently been shown in both that the exopolysaccharide is animalsl and in cystic fibrosis patients ,colonised with P aeruginosa. In addition, measurable levels of antibody are present in most normal adults and children,2 although considerably lower than those in CF patients colonised with this organism. Might the somatic antigen ("PA antigen") referred to in your editorial in fact be the antigenic determinant found on mucoid exopolysaccharide? Consistent with the report regarding the loss of "0" serotype reactions, we have recently found that 80% of mucoid P aeruginosa isolates from CF are lipopolysaccharide-rough isolates-that is, they have lost their serotype reactivity by virtue of loss of production of"0" specific polysaccharide side chains on the lipopolysaccharide.4Preliminary studies indicate that there is an association between loss of expression of serotype reactivity and expression of mucoid exopolysaccharide. Previous data on the lack ofimmunogenicity of mucoid exopolysaccharide were derived from only two patients and antigens, hardly enough to justify the pervasive feeling that mucoid exopolysaccharide is not an immunogen.
suggest that the obese should reduce their consumption of all kinds of food and not especially sugar. For someone writing from a sugar organisation, this suggestion has some commercial logic, but owes little to nutritional logic. Foods supply the body with energy (calories) and with nutrients. Obesity arises because of an excessive intake of energy, not because of an excessive intake of nutrients. Sugar is the only food that supplies nothing but energy, so that it is clearly the most obvious food that the obese should avoid. Vlitos implies specifically that vegetables might be one group of foods that could be reduced in order to cure overweight. For most people, avoiding all vegetables except potatoes would save fewer than 100 kilocalories a day and at the same time would reduce intake of vitamins A and C by some 30%. If potatoes were among the abandoned vegetables, there might be a saving of a further 100 kcal a day, and a total reduction of vitamin C by 50%. To suggest that it does not matter which food is reduced in treating overweight is like saying that it does not matter what is thrown overboard from a ship riding a severe storm; discarding the engine, the rudder and the radio equipment will reduce excessive weight just as well as discarding ballast. Vlitos goes
.
16 Holly
on to
Walk, LondonNW33
JOHN YUDKIN
CARDIOPULMONARY RESUSCITATION OF OLD PEOPLE
SIR,-The conclusion of Dr Gulati and colleagues (July 30, p 267) 1 Failure of the agrees with that of our own recently published resuscitation attempt was predicted not by age but by diseasecirculatory failure, acute stroke, metastatic cancer, uraemia,
study.
pneumonia, or sepsis. Of 294 patients in whom resuscitation was attempted at Beth Israel Hospital in Boston, 44% had pulse and blood pressure restored. 32% of those, or 14% of the original study group, were able to leave the hospital. While most patients were less active after discharge than before their illness, the predominant reason (well beyond limitation by organic disease) seemed to be fear of rearrest. Though initially depressed, almost all had recovered from their despondency when reinterviewed 6 months later. Your editorial concern (p 261) that the results of Gulati et al were "perhaps freakishly good" can thus be laid to rest. Other aspects of the editorial are disturbing. In particular, many thoughtful physicians will find surprising the notion that the unseemliness of "unwarranted resuscitative attacks" involving "stresses on fellow patients" should be seriously weighted against the rescue of individual lives. There may be little reason to attempt resuscitation where experience has shown it to be futile, but to withhold it from patients in whom there is a chance of success, on behalf of "dignity", is surely not warranted. Such distinctions will become easier only if knowledge about the natural history of resuscitation is systematically and unemotionally accumulated. "Death with dignity" has become a cliche that requires definition of the vantage point; it often exists only in the eye of the beholder. Given a choice between "dignity" and life, most of our surviving patients preferred life. (They did not, incidentally, remember the indignity of resuscitation.) We cannot, of course, know whether those who died preferred dignity. Department of Medicine, Beth Israel Hospital, Harvard Medical School, Boston, Massachusetts 02215, USA
FRANKLIN H. EPSTEIN SUSANNA E. BEDELL THOMAS L. DELBANCO
SE, Delbanco TL, Cook EF, Epstein FH. Survival after resuscitation in the hospital. N Engl J Med 1983; 309: 569-76.
1. Bedell
cardiopulmonary
mucoid
potentlyimmunogenic
Charming Laboratory, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
GERALD B. PIER
MALIGNANT DISEASE IN ATOMIC TEST OBSERVERS: POSSIBLE INTERACTION WITH SUNLIGHT
SIR,-Knox et al5 have drawn attention to the high apparent incidence of leukaemia and other reticuloendothelial neoplasms among those involved in atomic weapons tests in the South Pacific. Three explanations have been offered for these findings, should they withstand critical evaluation: (1) that the radiation exposure of the observers was vastly in excess of that expected; (2) that the cancer risk from low doses of radiation is much higher than has been supposed; or (3) that the apparent excess of leukaemias is due to some cause other than radiation. There is a fourth possibility-namely, the interaction of some other factor with the radiation exposure so that the effect of radiation is amplified-and I suggest that serious consideration should be given to excessive acute
sunlight. Light at wavelengths that can damage DNA (in the ultraviolet region, with and without photosensitisers) affects the immune system in vitro and in vivo in laboratory animals and in man.6-8 At least in part these effects may be attributed to a cytotoxic action on Langerhans cells present in the skin. A particularly telling effect is the observation of Roberts and Daynes9that internal tumours induced in mice by benzo(a)pyrene and methylcholanthrene showed a reduced latent period if the animals were pretreated with
exposure to
1. Macone
AB, Pier GB, Pennington JE, Matthews WJ Jr, Goldman DA. Mucoid Escherichia coli in cystic fibrosis. N Engl J Med 1981; 304: 1445-49. 2. Pier GB, Matthews WJ Jr, Eardley DD Immunochemical characterization of the mucoid exopolysaccharide of Pseudomonas aeruginosa. J Infect Dis 1983; 147: 494-503. 3. Bryan LE, Kureishi A, Rabin HR. Detection of antibodies to Pseudomonas aeruginosa alginate extracellular polysaccharide in animals and cystic fibrosis patients by enzyme-linked immunosorbent assay. J Clin Microbiol 1983; 18: 276-82. 4. Hancock REW, Mutharia LM, Chan L, Darveau RP, Speert DP, Pier GB. Pseudomonas aeruginosa isolates from patients with cystic fibrosis: a class of serum sensitive non-typable strains deficient in lipopolysaccharide "O" side-chains. Infect Immun (in press). 5. Knox EG, Sorahan J, Stewart A. Cancer following nuclear weapon tests. Lancet 1983; i: 815. 6. Strauss GH, Bridges BA, Greaves M, Hall-Smith P, Price M, Vella-Briffa D Inhibition of delayed hypersensitivity reaction in skin (DNCB test) by 8-methoxypsoralen photochemotherapy. Lancet 1980; ii: 556-59. 7. Moss C, Friedmann P, Shuster S. Inhibition of delayed hypersensitivity skin reactions in patients on methoxypsoralen photochemotherapy. Lancet 1980; ii: 922. 8. Hersey P, Bradley M, Hasic E, Haran G, Edwards A, McCarthy WH. Immunological effects of solarium exposure. Lancet 1983; i: 545-48. 9. Roberts LK, Daynes RA. Modification of the immunogenic properties of chemically induced tumours arising in hosts treated concomitantly with ultraviolet light. J Immunol 1980; 125: 438-47.
CYSTIC FIBROSIS AND PSEUDOMONAS INFECTION
SIR,-Professor Vlitos (Sept 17, p 688) says that I claim that "the obese are obese because they eat ’too many sweets". This is a considerable distortion of my letter of Aug 27 (p 517), in which I give, among the examples of the food I indict, whisky, beer, biscuits and cakes-the foods and drinks that people take to give pleasure rather than to alleviate hunger.
SIR,-I wish to comment on your editorial of July 30 (p 257). An unfounded belief has grown up that the mucoid substance produced by strains of Pseudomonas aeruginosa from cystic fibrosis patients does not generate an antibody response. It has recently been shown in both that the exopolysaccharide is animalsl and in cystic fibrosis patients ,colonised with P aeruginosa. In addition, measurable levels of antibody are present in most normal adults and children,2 although considerably lower than those in CF patients colonised with this organism. Might the somatic antigen ("PA antigen") referred to in your editorial in fact be the antigenic determinant found on mucoid exopolysaccharide? Consistent with the report regarding the loss of "0" serotype reactions, we have recently found that 80% of mucoid P aeruginosa isolates from CF are lipopolysaccharide-rough isolates-that is, they have lost their serotype reactivity by virtue of loss of production of"0" specific polysaccharide side chains on the lipopolysaccharide.4Preliminary studies indicate that there is an association between loss of expression of serotype reactivity and expression of mucoid exopolysaccharide. Previous data on the lack ofimmunogenicity of mucoid exopolysaccharide were derived from only two patients and antigens, hardly enough to justify the pervasive feeling that mucoid exopolysaccharide is not an immunogen.
suggest that the obese should reduce their consumption of all kinds of food and not especially sugar. For someone writing from a sugar organisation, this suggestion has some commercial logic, but owes little to nutritional logic. Foods supply the body with energy (calories) and with nutrients. Obesity arises because of an excessive intake of energy, not because of an excessive intake of nutrients. Sugar is the only food that supplies nothing but energy, so that it is clearly the most obvious food that the obese should avoid. Vlitos implies specifically that vegetables might be one group of foods that could be reduced in order to cure overweight. For most people, avoiding all vegetables except potatoes would save fewer than 100 kilocalories a day and at the same time would reduce intake of vitamins A and C by some 30%. If potatoes were among the abandoned vegetables, there might be a saving of a further 100 kcal a day, and a total reduction of vitamin C by 50%. To suggest that it does not matter which food is reduced in treating overweight is like saying that it does not matter what is thrown overboard from a ship riding a severe storm; discarding the engine, the rudder and the radio equipment will reduce excessive weight just as well as discarding ballast. Vlitos goes
.
16 Holly
on to
Walk, LondonNW33
JOHN YUDKIN
CARDIOPULMONARY RESUSCITATION OF OLD PEOPLE
SIR,-The conclusion of Dr Gulati and colleagues (July 30, p 267) 1 Failure of the agrees with that of our own recently published resuscitation attempt was predicted not by age but by diseasecirculatory failure, acute stroke, metastatic cancer, uraemia,
study.
pneumonia, or sepsis. Of 294 patients in whom resuscitation was attempted at Beth Israel Hospital in Boston, 44% had pulse and blood pressure restored. 32% of those, or 14% of the original study group, were able to leave the hospital. While most patients were less active after discharge than before their illness, the predominant reason (well beyond limitation by organic disease) seemed to be fear of rearrest. Though initially depressed, almost all had recovered from their despondency when reinterviewed 6 months later. Your editorial concern (p 261) that the results of Gulati et al were "perhaps freakishly good" can thus be laid to rest. Other aspects of the editorial are disturbing. In particular, many thoughtful physicians will find surprising the notion that the unseemliness of "unwarranted resuscitative attacks" involving "stresses on fellow patients" should be seriously weighted against the rescue of individual lives. There may be little reason to attempt resuscitation where experience has shown it to be futile, but to withhold it from patients in whom there is a chance of success, on behalf of "dignity", is surely not warranted. Such distinctions will become easier only if knowledge about the natural history of resuscitation is systematically and unemotionally accumulated. "Death with dignity" has become a cliche that requires definition of the vantage point; it often exists only in the eye of the beholder. Given a choice between "dignity" and life, most of our surviving patients preferred life. (They did not, incidentally, remember the indignity of resuscitation.) We cannot, of course, know whether those who died preferred dignity. Department of Medicine, Beth Israel Hospital, Harvard Medical School, Boston, Massachusetts 02215, USA
FRANKLIN H. EPSTEIN SUSANNA E. BEDELL THOMAS L. DELBANCO
SE, Delbanco TL, Cook EF, Epstein FH. Survival after resuscitation in the hospital. N Engl J Med 1983; 309: 569-76.
1. Bedell
cardiopulmonary
mucoid
potentlyimmunogenic
Charming Laboratory, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
GERALD B. PIER
MALIGNANT DISEASE IN ATOMIC TEST OBSERVERS: POSSIBLE INTERACTION WITH SUNLIGHT
SIR,-Knox et al5 have drawn attention to the high apparent incidence of leukaemia and other reticuloendothelial neoplasms among those involved in atomic weapons tests in the South Pacific. Three explanations have been offered for these findings, should they withstand critical evaluation: (1) that the radiation exposure of the observers was vastly in excess of that expected; (2) that the cancer risk from low doses of radiation is much higher than has been supposed; or (3) that the apparent excess of leukaemias is due to some cause other than radiation. There is a fourth possibility-namely, the interaction of some other factor with the radiation exposure so that the effect of radiation is amplified-and I suggest that serious consideration should be given to excessive acute
sunlight. Light at wavelengths that can damage DNA (in the ultraviolet region, with and without photosensitisers) affects the immune system in vitro and in vivo in laboratory animals and in man.6-8 At least in part these effects may be attributed to a cytotoxic action on Langerhans cells present in the skin. A particularly telling effect is the observation of Roberts and Daynes9that internal tumours induced in mice by benzo(a)pyrene and methylcholanthrene showed a reduced latent period if the animals were pretreated with
exposure to
1. Macone
AB, Pier GB, Pennington JE, Matthews WJ Jr, Goldman DA. Mucoid Escherichia coli in cystic fibrosis. N Engl J Med 1981; 304: 1445-49. 2. Pier GB, Matthews WJ Jr, Eardley DD Immunochemical characterization of the mucoid exopolysaccharide of Pseudomonas aeruginosa. J Infect Dis 1983; 147: 494-503. 3. Bryan LE, Kureishi A, Rabin HR. Detection of antibodies to Pseudomonas aeruginosa alginate extracellular polysaccharide in animals and cystic fibrosis patients by enzyme-linked immunosorbent assay. J Clin Microbiol 1983; 18: 276-82. 4. Hancock REW, Mutharia LM, Chan L, Darveau RP, Speert DP, Pier GB. Pseudomonas aeruginosa isolates from patients with cystic fibrosis: a class of serum sensitive non-typable strains deficient in lipopolysaccharide "O" side-chains. Infect Immun (in press). 5. Knox EG, Sorahan J, Stewart A. Cancer following nuclear weapon tests. Lancet 1983; i: 815. 6. Strauss GH, Bridges BA, Greaves M, Hall-Smith P, Price M, Vella-Briffa D Inhibition of delayed hypersensitivity reaction in skin (DNCB test) by 8-methoxypsoralen photochemotherapy. Lancet 1980; ii: 556-59. 7. Moss C, Friedmann P, Shuster S. Inhibition of delayed hypersensitivity skin reactions in patients on methoxypsoralen photochemotherapy. Lancet 1980; ii: 922. 8. Hersey P, Bradley M, Hasic E, Haran G, Edwards A, McCarthy WH. Immunological effects of solarium exposure. Lancet 1983; i: 545-48. 9. Roberts LK, Daynes RA. Modification of the immunogenic properties of chemically induced tumours arising in hosts treated concomitantly with ultraviolet light. J Immunol 1980; 125: 438-47.