107 as they did in their study. These differences are plotted in the small inserted figure. The line drawn for the data points in the figure (insert) corresponding to women fits almost exactly the relationship de0.038 x excess rived by James et al.-i.e., R.M.R. (MJ) weight (kg) - 0.381. Although the values which were calculated for men are slightly higher, close examination of the original data presented by James et al. will indicate that 8 out of 11 men also fell above their estimated regression line. The regression line they calculated was influenced primarily by the 58 women subjects used in their initial calculations. In general, their subjects appeared to be behaving in a higher predictable manner based on considerations of metabolic body size. James et al. note that the rate of metabolism decreases in relationship to decreased food intake. However, a part of this decrease results from a smaller metabolic body size after weight reduction. Calculation of the metabolic rate after weight reduction for the subjects indicated in fig. 2 of their ar-
ticle would suggest that approximately 0-7 MJ of the decrease in R.M.R. (average for 9 female subjects) was due to changes in metabolic body size. The remainder (05-0.6 MJ) appears in keeping with the usual effect of food restriction on the R.M.R. For example, a rough calculation for the R.M.R. for their typical obese subject yields a value of 8-9 MJ/day. A 6-8% decrease in the R.M.R. would be expected to occur with decreased intake in addition to the other effects related to changes in body weight. Their observed decrease in the R.M.R. does not appear unusual or greater than expected. In summary, a major conceptual error is made if one attempts to compare the R.M.R. of an obese individual to that of a "normal" individual of the same height. Department of Nutrition, College of Agricultural and Environmental Sciences, University of California, Davis, Davis, California 95616, U.S.A.
ROBERT B. RUCKER
In the city of Chicago, during 1975-76, there were 441 of S.LD.S., and the number of S.LD.S. deaths by age at death is shown in the accompanying figure. In contrast to the South Australian findings our data do not indicate any basic difference in seasonality between S.I.D.s. deaths under three months and those at an older age. Analysis of seasonality of the three age-at-death groups indicated no significant differ-
( f2=203; p=0-l).
It remains to be determined whether Beal’s interesting findings are due to some unusual characteristic of S.I.D.S. in South Australia or to some unknown selection bias peculiar to the area.
of Community and Family Medicine, Loyola University Stritch School of Medicine, Maywood, Illinois 60153, U.S.A. Medical Examiner’s Office, Cook County, Illinois
JULIUS GOLDBERG ROBERT J. STEIN
ROLE OF THE CHEMICAL PATHOLOGIST
SIR,-I was disappointed to read in your review of the book Metabolic and Endocrine Emergencies (June 3, p. 1187) that the chemical pathologist "is more likely to suggest further tests than to help institute appropriate therapeutic measures". Although I suspect that this was "tongue-in-cheek" it seems to reflect a widespread attitude which does nothing to improve recruitment to a specialty which is already short of medical man-
power.’ Far from being capable only of indicating further tests most chemical pathologists have a wide experience of, and are very able to help with the management of, just such emergencies as your review discusses. The chemical pathologist, because of the large number of results which he sees from all over the hospital, can amass a great deal of experience in the diagnosis and management of a wide variety of chemical disorders, including fluid and electrolyte, endocrine, toxicological and nutritional
SEASONAL VARIATION IN SUDDEN-INFANT-DEATH SYNDROME
SIR,-Dr Beal’ has found that in South Australia death in sudden-infant-death syndrome (S.I.D.S.) under three months of age is independent of seasonality while s.LD.s. deaths at four months or older show a decided peak during the winter months. Our data, however, differ significantly from Beal’s.
In what other specialty is it possible to combine the sciences of clinical medicine, biochemistry, physics, electronics, statistics, computing, and pharmacology into a single career? Perhaps if the portrayal of chemical pathology as a "Cinderella" could be avoided, recruitment of good medical graduates to this satisfying branch of medicine would improve. Department of Pathology, Rotherham District General Hospital, Oakwood, Rotherham S60 2UD
P. R. BECK
CONTROLLED TRIALS IN SURGERY
SIR,-We would like to strongly endorse the need, stressed by Professor Spodick and others2 for standards of assessment and reporting of new surgical procedures and applications of established procedures. The revised version of the Declaration of Helsinki as produced by the 29th World Medical Assembly, Tokyo, Japan in 1975, included a new emphasis on the necessity for accuracy in publishing results of research projects. Section 1.8 now reads: "In publication of the results of his or her research, the doctor is obliged to preserve the accuracy of the results. Reports of experimentation not in accordance with the principles laid down in this declaration should not be accepted for publication." The italics are ours. We would like to add an additional plea. Work that is properly done and accurately reported, is worth publishing even if the result is negative. Indeed, a reliable negative result may well be more valuable than unreliable information that mis-
leadingly projects S.I.D.S.
age at death and month of death,
1. Association of Clinical Biochemists News Sheet no. 167, 2. Spodick, D. H., and others, Lancet, 1978, i, 1214.
108 worthwhile. And this refers research.
Department University of Melbourne, Royal Melbourne Hospital,
F. FORBES ANTHONY R. MOORE
Victoria 3050, Australia
&bgr;2-MICROGLOBULIN, A TUMOUR MARKER OF
has resulted in
majority in favour of more than two to one. This looks impressive until it is realised that the "yes" vote represents well a
under half the electorate, of whom less than 68% voted. This sort of turn-out, which might be considered quite good in a Parliamentary by-election, is less acceptable in our case. If we are as concerned about the issue’as we are led to believe, how is it that nearly a third were too apathetic to vote? The answer must lie in the disturbing reports from many parts of the country about non-receipt of ballot papers. In my own hospital three of the nineteen consultants had still not received papers by the closing date, and others got the papers only after making personal requests. Indeed the figures could well be worse because I have not questioned all of them. The result is at most a mandate to refer the proposals for pricing. A later second ballot has been mentioned but never confirmed, although I know several colleagues who would probably not have voted "yes" if they had not believed they were guaranteed a second personal chance of rejection. With the highly unsatisfactory distribution of papers the first time this second ballot is now essential, and it must be done more efficiently. It should not be too difficult to obtain upto-date lists of consultants and senior registrars from their employing authorities. If these same authorities made the lists available in the hospitals under their jurisdiction well before the next ballot, we would have the opportunity to check that we were at least on the register. The second ballot could then be carried out without the indecent haste which seems to have characterised the first. Hill House, Great Bourton, Banbury, Oxon.
P. W. FISHER
PLASMAPHERESIS IN RAYNAUD’S DISEASE
SIR,-Professor Klinenberg and Dr Wallace’ report failure
improve the condition of two patients with Raynaud’s disby plasmapheresis. Our team at King’s College Hospital has in the past twelve months treated twelve patients (eight diagnosed as Raynaud’s and four as "other small-vessel disease"). Ten patients showed improvement, as assessed by digital-artery testing with ultrasound2 and the other two showed no change. Two of the patients who had improved by objective criteria denied any subjective improvement. The two patients who did not show increased digital-artery patency after plasmapheresis judged themselves as improved. The first patient treated had gangrene of the fingertips. Treatment began on June 23, 1977, and after six plasma exchanges her digital arteries were fully open and have remained open since that time, the gangrene has healed, and she is pain-free. to
SiR,—j-microglobulin (3z M.G.) is a polypeptide (molecular weight 11 800) found by Berggard and Bearnl in the urine of patients with tubular renal diseases. This microglobulin is found on the cytoplasmic membrane of all nucleated cells,2 where it participates in the structure of HLA antigens.3 Its normal plasma concentration is 0-8-2-4 g/1. It rises in the presence of glomerular dysfunction, while its urinary excretion increases in cases of tubulopathy. Its medical applications were first studied in nephrology, then in cancer and blood disorders.5-7 Interpretation of high &bgr;2-M.G. values limited by the fact that such increases may result from augmentation of synthesis or from diminution of excretion due to renal dysfunction. For this reason, work on non-renal diseases has excluded patients with a serum-creatinine above 1.2 mg/dl. Thus, a high proportion of cases, mainly those with advanced proliferative diseases, were not studied. We have tried to avoid this restraint by discriminating one cause of increase from another, assuming that the part due to renal dysfunction may be estimated from the increase in creatinine. In 795 blood-samples measured in patients without tumours, the correlation between 2-M.G. and creatine (Y) (both in g/ml) was very high
(r=0.9849): Loge -M.G.=3-834-3.96 Y+2.94 y2-0-476 y3+0.0252 y4 From this relation, a table was constucted which gives the expected (or theoretical) 2-M.G. level as calculated from the creatinine value. The ratio M/Th (measured/theoretical) for the 795 patients with various non-neoplastic diseases extended from 0.25 to 2.5 (median 0.9). In 2596 patients with solid tumours it varied from 0-25 to 6 (median 1.1). In 333 patients with lymphoproliferative diseases, it extended from 0.5to 12.7 12.7 (median 2.5), and results for some of these diseases are shown in fig. 1. Myeloma (fig. 2) was staged according to the Durie and Salmon8 classification and the non-Hodgkin lymphomas (fig. 3) were classified by the Ann Arbor9 scheme. The
1. 2. 3.
Berggard, I., Beam, A. G.J. biol. Chem. 1968, 243, 4095.
Evrin, P. E., Wibell, L. Clin. chim. Acta, 1973, 43, 183. Nakamuro, K., Tanigaki, N., Pressman, D. Proc. natn. Acad. Sci. U.S.A. 1973, 70, 2863. 4. Evrin, P. E., Wibell, L. Scand. J. clin. Lab. Invest. 1972, 29, 69. 5. Kithier, K., Cejka, J., Belamaric, J., Alsarra, F. M., Peterson, Vaitkevicius, J., Poulik, M. D. Clin. chim. Acta, 1974, 52, 293. 6. Shuster, J., Gold, P., Poulik, M. D. ibid. 1976, 67, 307. 7. Kin, K., Sakurabayashi, I., Kawai, T. Gann. 1977, 68, 427. 8. Dune, B. G., Salmon, S. E. Cancer, 1975, 36, 842. 9. Carbone, P. P., Kaplan, H. S., Musshoff, K., Smithers, D. W., Tubiana, M. Cancer Res. 1971, 31, 1860.
I agree that much needs to be done, but what we have established is a sensitive non-invasive test for digital arterial patency or occlusion and a method of objective assessment of improvement in a condition difficult to define and difficult to treat.
Department of Biomedical Engineering, King’s College Hospital Medical School,
L. T. COTTON
London SE5 8RX 1. 2.
Klinenberg, J. R., Wallace, D. Lancet, 1978, i, 1310. Talpos, G., Horrocks, M., White, J. M., Cotton, L. T.
Fig. 1— -M.G. M/fh ratios in patients with lymphoproliferative disorders and in 245 healthy individuals (controls).