URINARY ELECTROLYTES IN RENAL LITHIASIS

1391

Letters

to

early,9 because of the danger of aspiration 10) feeding provides premature infants with an optimal amount of calories which enables them to remain in a good growth percentile.

the Editor

too

PLAY AND THE SICK CHILD

SIR,-Dr. Jolly (Dec. 14, p. 1286) states the case well for the provision of play for children in hospital. The Save the Children Fund and Mrs. Susan Harvey are to be commended for undertaking this pioneer work, providing and paying for the play-specialist ", and supplying the play material. The S.C.F. are now running 14 such play units, which are costing it E10,000 a year. If we are to accept the therapeutic benefit of this work should not the cost be borne by the hospital (4 are paying some of the cost), and not by a voluntary body which has such heavy demands on its funds ? I should like to bring to the notice of your readers the booklet Play in Hospital, obtainable from the U.K. National Committee of the World Organisation for Early Childhood Education (O.M.E.P.), c/o Housing Centre Trust, 13 Suffolk St., London S.W.1, price 7s. 6d., post free 8s. "

London W.I.

DAVID MORRIS.

PREMATURE FEEDING?

SIR,-We summarise here our results in the feeding of 300 premature infants consecutively admitted to this clinic from Dec. 1, 1964, to Jan. 31, 1967. Of 20 admitted weighing below 1000 g. 4 survived; of 65 weighing 1001-1500 g. 34 survived; of 132 weighing 1501-2000 g. 106 survived, and of 83 weighing 2001-2500 g. 67 survived. The standard feeding policy was the administration every 2-3 hours of 5% glucose solution in the first 6-12 hours of life, and of half-skimmed milk (63 C. and 32 g. protein per 100 ml.), or, for premature infants weighing less than 1200 g., completely skimmed milk (58 C. and 4-4 g. protein per 100 ml.) during the 12th to 24th hours of life. Quantities were roughly calculated by multiplying kg. x day of life x 17 ml., and after the lst week of life premature infants were offered 200 ml. of milk per kg. body-weight per day. Premature infants in distress received 65 ml. of fluids (glucose and sodium-bicarbonate solution) per kg. per day intravenously until they could be fed.l If our mean weight-gain graphs are compared with the classical curves obtained by Dancis et al. in 1948 2 from a study in many nurseries, where the infants were fed on the 3rd day of life, it is apparent that our premature infants weighing less than 1750 g. gained weight at a much faster rate. The earlier and more abundant feedings mainly influenced the weight curves of the smaller premature infants (under 1750 g.); the weight curves of bigger (1750-2000 g.) babies were not influenced very much, and there were no differences in the 2000-2250 g. and 2250-2500 g. groups. As better criteria of growth, the intrauterine weight-charts of Lubchenco et al.3 were used for the closer follow-up of 85% of our premature infants, on whom valid gestation data were available. In the 1001-1500 g. group 75% of the infants remained in their own percentile of growth. 73% of the 1501-2000 g. group also kept in their percentile of growth. In the 2001-2500 g. group 20% of the infants followed their own percentile of growth, while the remaining 80% fell into the percentile immediately lower than theirs; but it must be underlined that many of the premature infants in this group were referred to our clinic because of some abnormality. It is not easy to compare the growth of premature infants from different countries, since it depends upon multiple biological and environmental factors (genetic, perinatal, social, transportation, and nursery set-up and experience of personnel). However, our data suggest that a schedule of early 4-8 (but not 1. 2. 3. 4. 5. 6. 7. 8.

Usher, R. Pediat. Clins., N. Am. 1961, 8, 525. Dancis, J., Holt, L. E., Jr., O’Connell, J. R. J. Pediat. 1948, 33, 570. Lubchenco, L. O., Hansman, C., Dressler, M., Boyd, E. Pediatrics, Springfield, 1963, 32, 793. Reardon, H. S. Pediat. Clins., N. Am. 1959, 6, 181. Usher, R. Pediatrics, Springfield, 1959, 24, 562. Nicolopoulos, D. A., Smith, C. A. ibid. 1961, 28, 206. Goldman, H. I., Karelitz, S., Aczs, H., Seifter, E. ibid. 1962, 30, 909. Keitel, H. G., Chu, E. Pediat. Clins., N. Am. 1961, 8, 471.

Paediatric Clinic of Athens University, St. Sophie’s Children’s Hospital, Athens 608, Greece.

D. NICOLOPOULOS L. MORPHIS E. GAVRIELIDOU.

HYPERCALCÆMIA AND CALCIUM RESIN SIR,-With interest I read the articles by Dr. Papadimitriou and his colleagues (Nov. 2, p. 948) and by Dr. Sevitt and Dr. Wrong (Nov. 2, p. 950) on the effect of calcium resin (’ Zeocarb 225 ’) in patients with chronic renal failure either on haemodialysis or without any dialysis. Hypercalcarmia seems to be a striking consequence of the administration of zeocarb 225. I doubt whether this can be explained solely by liberation of calcium (from the calcium resin) in exchange for potassium. Why should a calcium resin act as a more potent calcium supplier than calcium lactate or other calcium compounds, especially when total liberation of calcium from the resin seems unlikely ? We should not forget the gut’s impaired ability to absorb calcium in uraemia." It is well established that potassium is absorbed in competition with calcium by the intestinal mucosa 12-14-i.e., potassium diminishes calcium absorption. After administration of a calcium resin, potassium ions of the intestinal contents are fixed to the resin. Calcium ions from food, intestinal juices, and exchange calcium from the resin can now be absorbed by the small intestine to a greater extent because there is hardly any potassium left. This is true not only in health but also, and even more, for the uraemic patient who has an increased potassium concentration of the intestinal juices due to secondary hyperaldosteronism.15 There is

no

satisfactory explanation for

absorption from

the intestine in uraemic

impaired calcium patients. Probably

the

there are several causes: high potassium concentration of the intestinal juices might be one. Incidentally Dr. Chugh and his colleagues (Nov. 2, p. 952) report on aluminium resin and hyperkalxmia. They demonstrate the powerful action of aluminium resin in lowering serum-calcium in one patient. Would this resin not be an ideal means to reduce the hypercalcaemia commonly associated with malignant tumours ? Pathologisches Institut der Universität Zurich, Kantonspital, 8006 Zurich, R. HALBRITTER. Switzerland.

URINARY ELECTROLYTES IN RENAL LITHIASIS SiR,ňThe conclusion of Dr. Papadimitriou and his colp. 1002) that " there was no significant difference in the urinary sodium/calcium ratio" between stone-formers and controls must be assessed in relation to the method of study that they adopted for their investigation. The urinary sodium/calcium ratio is determined by a multiplicity of factors, among which are environmental conditions, the state of health of the individual, and variations in diet. A comparative study, under standard conditions, of the urinary constituents involved in the ratio is therefore of little value. It is well established that, except when sweat losses are significant, the daily urinary sodium output is an accurate measurement of sodium intake. The subjects studied by Dr. Papadimitriou and his colleagues could therefore be expected to have a narrow range of sodium output predetermined by the standard diet containing 150-200 meq. of sodium. The standard diet of 500-800 mg. of calcium over a short period would not, however, appreciably influence pre-existing

leagues (Nov. 9,

9. Smallpeice, P., Davies, P. Proc. R. Soc. Med. 1964, 57, 1173. 10. Wharton, B. A., Bower, B. D. Lancet, 1965, ii, 969. 11. Ogg, C. S. Clin. Sci. 1968, 34, 467. 12. Schachter, D., Dowdle, E. B., Schenker, H. Am. J. Physiol. 1960, 198, 263. 13. Schachter, D., Dowdle, E. B., Schenker, H. ibid. p. 275. 14. Moll, H. Ch. in Transport und Funktion intrazellularer Eleklrolyte; p. 139. Berlin, 1967. 15. Wrong, O., Metcalfe-Gibson, A. Proc. R. Soc. Med. 1965, 58, 1007.

1392 differences in urinary calcium output. The data are therefore valid as regards relative differences in urinary calcium but meaningless as regards the urinary sodium/calcium ratio. The statement of Dr. Papadimitriou and his colleagues that the Bantu " have a low calcium excretion due to a low intake " is incorrect. It has been shown that the daily urinary output of calcium is equally low (81±56 mg.) in the urban and the rural Bantu, although the calcium intake in the former is 800 ±200 mg. per day and 200-450 mg. per day in the latter. This racial peculiarity requires elucidation. MONTE MODLIN. Cape Town.

probably

HUMIDIFICATION OF INSPIRED AIR

SiR,—Ihave tried Dr. Lomholt’s method of administering oxygen through one nostril (Dec. 7, p. 1214) and can confirm that, provided the gas is adequately warmed and humidified, it is quite acceptable. I do not, however, agree that it cannot be done with a nebuliser, or that the complicated and rather

dangerous arrangement that Dr. Lomholt uses is necessary. I used a standard Wright nebuliser1 which, at a pressure of 80 lb. per sq. in., gives a flow of rather more than 30 litres unstirred water-bath at 45°C. The temperature of the gas at the nose was only about 30°C, but it was supersaturated, as shown by the fact that a mist of distilled water not only emerged from the end but also came out of the mouth. If supersaturation is thought to be undesirable, the nebuliser gas can easily be diluted with dry gas. The danger of Dr. Lomholt’s humidifying and heating arrangement is that, as he himself points out, any breakdown in communication between the temperature sensor in the nose and the heater could lead to scalding. per

minute, immersed in

an

M.R:C. National Institute for Medical Research, Mill Hill, London N.W.7.

EMULSIFYING

EUSOL/LIQUID

B. M. WRIGHT.

Cambridge.

PARAFFIN

S.

J. HOPKINS.

GASTRIC IRON-BINDING IN HÆMOCHROMATOSIS SIR,-Dr. Smith (Nov. 23, p. 1143) reported no significant difference in the iron-binding ability of fasting gastric juice in normal subjects and patients with hsmochromatosis. Since our paper was published (Oct. 19, p. 844) an additional five patients with hsemochromatosis have been studied, and our previous finding of absent or greatly decreased gastric iron-binding in this condition has been confirmed when using the radioiron-solubility test as described by Davis.3 One patient, a pregnant woman aged 23 years, had a positive family history of haemochromatosis and her transferrin was fully saturated. The iron-binding ability of fasting gastric juice measured by the method of Davis3 was 0-003 mg. per ml., whereas it measured 0-055 mg. per ml. by the method of Mrs. Wynter and Dr. Williams.4 We have now adopted the ’latter method routinely, because it gives more accurate readings with low concentrations of iron-binding substances. We are unable to resolve the reasons for the divergent results of other workers and ourselves. It is unlikely to be 1. 2. 3. 4.

to

answer.

Wright, B. M. Lancet, 1958, ii, 24. Hopkins, S. J. Pharm. J. 1940, ii, 28. Davis, P. S. Proc. Aust. Ass. Clin. Biochem. 1965, 1, 190. Wynter, C. V. A., Williams, R. Lancet, Sept. 7, 1968, p. 534.

C. G. LUKE P. S. DAVIS D. J. DELLER.

Department of Medicine, University of Adelaide, Adelaide, South Australia.

ALTERATIONS OF FIBRINOLYSIS AND BLOOD COAGULATION taken from a vein in cases of heatstroke SIR,-Blood coagulates -quickly and then the clot is soon dissolved. No doubt the underlying mechanism is similar to that described by Dr. Cohen and his colleagues (Dec. 14, p. 1264). I do not think that this observation has been recorded before. Epping, FRANK MARSH. Essex.

EARLY DETECTION OF CANCER Sir,- read, in fact twice, the article by Professor Brooke (Dec. 14, p. 1289). Surely every medical student knows the difference between " early diagnosis ", a measurement of the time between a symptom first being noticed and the diagnosis being confirmed, and " early stage diagnosis ", a clinical estimate of the advancement of the disease. They also realise that the most important factor in prognosis is the type of cell of which the tumour is composed, undifferentiated " being quickly disseminating, and " well differentiated" "

slowly disseminating.

surprise that a large number of five-year-survival test: they are all cases of well-differentiated growths, otherwise they would be dead. This is no argument against trying to obtain early diagnosis, for some of the tumours caught will be between It should be

late-diagnosed

SIR,= I"he report by Mr. Summers and Mr. McLaughlin (Dec. 14, p. 1299) on the value of’Unemul ’ in the preparation of emulsions of eusol and liquid paraffin is interesting, but not new. A similar comment was made 2 nearly 30 years ago. Pharmaceutical Department, Addenbrooke’s Hospital,

salivary contamination of gastric juice, although saliva iron-binding properties. Case selection also seems unlikely, because despite the controversy on the definition of idiopathic hasmochromatosis, the results reported from all groups have been consistent within themselves. Subtle differences in technique might provide the due

possesses considerable

no

matter

cases

of

pass the

extremes of undifferentiated and well-differentiated, and therefore be cured (i.e., five-year survival). This Association will continue to urge women to make a habit of selfexamination of the breasts once a month. I agree with Professor Brooke that every effort should be made to catch cancer of the breast in a pre-symptomatic stage, but he does not mention X-ray mammography. (Thermography is, I understand, of little use.) Finally, I fear that Professor Brooke’s article will " disseminate " gloom among patients who hear of it, and will encourage the wait-and-see practitioners, who tell their " patients, a lump is nothing to worry about, come and see me again if it gets larger or begins to hurt." MALCOM DONALDSON 6 Queen Street, Oxford OX1 1BR. Honorary Director,

the

can

Cancer Information Association.

SIR,-Professor Brooke’s remarks

on

the " early "

cancer

find an echo in those of us closely concerned with the treatment of cancer. It is remarkable that the fallacy of equating early diagnosis, in the sense of short history, with better prognosis, has persisted for so long. Fortunately, more attention is being focused on this question, and the type of cross-classification which includes rate of growth as well as extent of tumour, as suggested by Ginsburg,6 is likely to prove rewarding. Evidence that prognosis can already be assessed with some precision when several features, including length of history, are combined, is available for malignant melanoma.’7 It may be, though verification of this is at present impos-

will

5.

6. 7.

surely

Reilly, P. L., Davis, P. S., Deller, D. J. Nature, Lond. 1968, 217, 68. Ginsburg, G. P. Lancet, Nov. 16, 1968, p. 1078. Cochran, A. J. ibid. p. 1062.