612

two case reports. The low basal gastric acid output andsubstantial response to pentagastrin exhibited by case 2 is notunusual in Zollinger-Ellison syndrome. In a large series in theU.S.A. one in five cases produced less than 5 mmol H+/hunder basal conditions and 45% more than doubled their acidsecretion after stimulation.4 4

It is important to recognise that a normal basal acid outputand response to stimulation by no means excludes Zollinger-Ellison syndrome. This diagnosis should be considered inany case of unexplained diarrhoea or steatorrhoea,particularly if abnormalities of gastric or jejunal mucosalpattern have been noted on barium studies or biopsy and ifthe serum calcium level is raised. The finding of a largevolume of acid duodenal juice during investigations ofsuspected pancreatic steatorrhoea probably indicates

Zollinger-Ellison syndrome.

We thank Dr Mark Aitken for referring case 1 and Dr Michael Clark for

helpful criticism. P.D.F. thanks the Wellcome Trust for financial support.- Requests for reprints should be addressed to P. D. F., Department of

Gastroenterology, St Bartholomew’s Hospital, West Smithfield, LondonEC1A 7BE.

REFERENCES

1. Maurice J. Doctors raise cancer fears over "wonder drug" used by millions. SundayTimes 1981. Jan 11. p 4.

2. Ellison EH, Wilson SD. The Zollinger-Ellison syndrome: reappraisal and evaluation of260 registered cases. Ann Surg 1964; 160: 512-16.

3. McGuigan JE. The Zollinger-Ellison syndrome. In: Sleisinger MH, Fordtran JS, eds.Gastrointestinal disease. Philadelphia: W.B. Saunders, 1978: 860-75.

4. Ayogi T, Summerskill WHJ. Gastric secretion with ulcerogenic islet cell tumor.

Importance of basal acid output. Arch Intern Med 1966; 117: 667-72.

Methods and Devices

MEASUREMENT OF INTENSITY OF HEARTSOUNDS AND MURMURS

R. S. SHARMA

Department of Medicine Medical College, E-42, 45 Bungalows,South TT Nagar, Bhopal, Madhya Pradesh, India

A MORE objective measure of the intensity of heart sounds andmurmurs than the grades 1-5 generally used was tested on 25murmurs and 25 heart sounds. Every murmur and sound wasassessed under identical circumstances by five examiners. Whetherthe diaphragm or bell was used depended on circumstances-e.g.,the bell was used for mitral stenotic murmurs. Easily standardisablepaper discs, 0 - 5 mm thick and cut to the size of diaphragm or bell,were progressively inserted between the stethoscope and chest walluntil the sound or murmur became inaudible. The total thickness ofdiscs used was the measure of intensity-e.g., a mid-diastolicmurmur made inaudible by the insertion often discs was describedas a 5 mm murmur. The assessments made by the five examinersshowed close agreement (see accompanying table).This system of measuring intensity of heart sounds and murmurs

is cheap and has several advantages over the conventional gradingsystem. The end-point (inaudibility) is easily defined, so thatreliability of assessment does not depend on experience in

recognising intensity of murmurs. This feature was shown in ourstudy in that although members of the examining team ranged frominterns to consultants, their findings showed close agreement.Reproducibility of results by different examiners does depend onthe possession of normal hearing by the examiners; but the

technique can be used by a doctor with impaired hearing if hefollows up the patient himself.Changes in intensity caused by change in posture or phase of

respiration or by various manoeuvres can be picked up by this

REPRODUCIBILITY OF FINDINGS AMONG FIVE EXAMINERS

* Stenotic, regurgitant, and functional murmurs.

f lst heart sound in mitral area or 2nd sound in aortic or pulmonary area; onuone heart sound graded in each case.

technique. Doubts about the selective conduction of a murmur in adirection can be settled by measuring the intensity at pointsequidistant from site of maximum intensity. Another advantage isthat as one murmur disappears with interposition of discs, anothermurmur, if present, may be heard and timed better. It also aids in

identifying "apparently continuous" murmurs.

I thank the other four examiners-Dr A. Khan, Dr P. N. Pachori, Dr K. XSimhal, and Dr M. K. Chaure.

Reviews of Books

Management of the Cardiac Patient with Renal FailureEdited by D. T. Lowenthal, R. S. Pennock, W. Likoff, and G. Onesn,Hahnemann Medical College and Hospital, Philadelphia, PennsylvamaPhiladelphia: F. A. Davis. 1981. Pp. 204.$37.50.

THE title of this book is misleading. It does not deal, as I thought atfirst, with renal failure after myocardial infarction or cardiac

surgery. It is exclusively concerned with cardiac disease in patientsmaintained on chronic dialysis. This is not as small an area as mightappear. In the United States the size of the treated population hasrisen exponentially since the extension of Medicare in 1972 to coverdialysis. Cardiovascular disease is the major cause of death amongstpatients on dialysis. When so much costly expertise has beeninvested in maintaining them it is reasonable to expect that an equalamount of cardiological skill will be deployed. This cannot,however, be assumed. The problems presented by cardiac disease ona renal unit are in many respects specific. Atheroma pursues anaccelerated course, severe hypertension is common, fluid and

electrolyte balance is under constant threat, uraemic pericarditismay on occasions present a particular clinical problem, and drughandling is altered.A cardiologist in the United Kingdom is likely to have little

clinical experience of the dialysis patient. Simply because theAmerican experience is so much greater than ours, any Americanbook which focusses on these problems should be studied withinterest. This book which comes from a unit which has an

international reputation in the haemodynamic aspect of renaldisease is particularly valuable, dealing as it does with each clinicalproblem in turn. The style is clear, the recommendations aredecisive, and the train of thought is logical. Although nineteenauthors contribute, there is very little overlap. I have only twominor qualifications. A British reader will find the list ofrecommended drugs a little restricted; the section on angina, forinstance, mentions only nitroglycerine and propranolol. Some ofthe authors tend to forget that investigation is a guide to

management and list investigations which are likely to yield anabnormal result, whether the tests have any therapeutic relevance ornot. Despite this common failing, the book is a timely and originalcontribution to an area of growing importance. It is well produced,although it contains one memorable misprint, when we are told thatresuscitation from ventricular fibrillation may "decrease morality"The book should be purchased by every renal unit and left

prominently but diplomatically in the path of visiting cardiologists.The lot of our own diminutive number of dialysis patients ma}thereby be improved.Department of Medicine,Leicester Royal Infirmary J. D. SBB.BLES

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Basic Principles of Cancer ChemotherapyKenneth C. Calman, University of Glasgow, John F. Smyth, University ofEdinburgh, and Martin H. N. Tattersall, University of Sydney. London:Macmillan. 1981. Pp. 160..E15.00 (hardback); 1:5.95 (paperback).

ALTHOUGH cancer is the second commonest cause of death, therehas been little undergraduate teaching of the principles of cancercare. Students are traditionally taught about the surgicalmanagement of some of the solid tumours, but little else. For mostdoctors further training in cancer care is limited, and theintroduction of improved radiotherapy and, more recently, cancerchemotherapy, has meant that many doctors have little experienceof these specialties.

-

.

The aim of this book is modest-to provide basic information onthe mechanisms of action and uses of the common anticancer drugs.A more ambitious goal would have been self defeating. Thechemotherapeutic management of cancer and the clinical use ofthese drugs cannot be gleaned from a textbook; they can only belearnt in the clinic, supplemented by the reading of currentpublications.Short chapters on tumour biology, basic biochemistry, and

pharmacology form the first part of the book. Subsequent chaptersdiscuss specific drugs and the principles underlying combinationchemotherapy as well as the complications of drug treatment. Thestaging and evaluation of patients is covered in a separate chapter, asare tumour immunology and drug interactions. Pharmacologicalinformation on the commonly used anticancer drugs is included inan appendix where, appropriately, there is no information on drugcombinations or the specific treatment of different tumours. This isnot a "treatment cookbook", and the authors have studiouslyavoided a therapeutic approach. There are no references, andalthough this is appropriate in a basic textbook, a short bibliographyof specialist books on the pharmacology and biochemistry ofanticancer drugs would have been desirable.The book is concise and well produced and the figures are clear. It

is a good basic introduction to cancer chemotherapy that will appealboth to students and to doctors developing an interest in thespecialty.C R.C. Medical Oncology Unit,Southampton General Hospitaf CHRISTOPHER WILLIAMS

UroradiologyThomas Sherwood, University of Cambridge. With contributions fromAlan J. Davidson and Lee B. Talner. Oxford: Blackwell: 1980. Pp. 351.;E35.

"Vesico-ureteric reflux and chronic pyelonephritis are terribletwins: everyone realises they are related, but no-one knows who theparents are". This is the opening sentence in a section on dilatedureters in perhaps the best textbook on uroradiology to have beenpublished. It characterises Professor Sherwood’s elegant style thatmakes this book both a pleasure to read (it is difficult to put down)and a mine of information. Although Sherwood states that his bookis a personal view of what is important and interesting in

uroradiology, it is at the same time a very comprehensive and well-illustrated work, which at all times emphasises the physiological andclinical aspects of the urinary tract and places the many imagingtechniques available for the renal tract in proper perspective.Sherwood sensibly tackles radiology from a point of view of being

faced with urological problems rather than according to theconventional anatomical/pathological categorisation. Thus after anintroductory section on the diagnostic tools and a splendid one onhypertension and the renal tract, the body of the book deals withpresenting problems such as renal masses, trauma, incontinence,infertility, and so on. The only omission is a section on

transplantation, and too few words are allotted to renalembolisation, a topic which the author acknowledges is progressingby leaps and bounds.The sections on urological problems in children and on

urodynamic studies are particularly good, but it is the sound advicewhich abounds on every page that makes the book essential for alldoctors interested in the urinary tract. Not only does one enjoy the

Sherwood aphorisms ("overnight dehydration is not a reliable wayof assuring maximal urine concentration-it is a short period in thebody’s overall water household") but one also gains a marvellousperspective about the rationale for investigating specific urologicalproblems coupled with a sound, basic grounding in imaging of theurinary tract. A future, and I hope a larger, edition will surelyinclude more interventional radiology.Department of Radiology,Royal Free Hospital, London R. DICE

Recent Advances in Urology/AndrologyNo. 3. Edited by W. F. Hendry, St Bartholomew’s Hospital, London.Edinburgh: Churchill Livingstone. 1981. Pp. 361. ;E20.

THE Recent Advances series appeals most to those who do not readand file regularly all their general and specialist journals and whofind the Year Books tedious. Their popularity is, therefore, assured,provided a high standard is maintained. This is guaranteed in thepresent volume on urology/andrology, by twenty-sevendistinguished contributors.There is good news regarding treatment for disorders ranging

from incontinence, impotence, and infertility to tuberculosis andtumours. Unfortunately, there is evidently little progress to bereported on prevention, perhaps because of the excessiveorientation of research towards the laboratory. Even the importantdiscovery- that the increasing incidence of renal calcium oxalatestones in the Western world is related to dietary characteristics suchas fibre-deficiency and excess of refined carbohydrates, animalprotein, and dairy produce-receives no -mention. There are

striking geographical and racial differences in the incidence of manyurological diseases, and further epidemiological studies are urgentlyrequired. It is a pity too that the chapter outlining a modest successfor overdistention in "instability" of the bladder was not offset byanother recording the far more basic re-discovery of anxiety as thecommonest cause for painless frequency and urgency.There is the tendency for superspecialists to understate the

risk of failures and complications, which are bound to be commonerin less experienced hands. For example, in praising the newcontinuous-irrigation resectoscopes, it should be pointed out that,with the common Iglesias pattern, suction may easily be applied tothe membranous urethra, so that a stricture forms. The serioushazards of percutaneous nephrostomy or pyelostomy are also notmentioned, and in one of the two papers advocating cytotoxictherapy the possibility of complications (sometimes fatal) is ignored.No results are cited for the use of inflatable prostheses inincontinence nor is the high re-operation rate referred to.Two minor irritating features are, firstly, the poor-quality

illustrations in the otherwise excellent chapter on hypospadias and,secondly, the use of the term "therapeutic modalities" instead oftherapies in a book published in the U.K.

Progress is undoubtedly being made in urology, but it is highlyregrettable that, as indicated in the section on the logistics ofprostatectomy, so many patients with urological problems in theU.K. will be deprived of the benefits of all these recent advancesbecause of a shortage of urologists.Department of Urology,Royal Liverpool Hospital NORMAN GIBBON

Operative Techniques in Vascular SurgeryEdited by J. J. Bergan and J. S. T. Yao, North Western Medical School,Chicago. New York: Grune and Stratton. London: Academic Press. 1981.Pp. 310.$59.50; 37.40.

IN recent years Professor Bergan and Dr Yao have organisedvascular symposia at the North Western Medical School, and thisbook is the result of their latest meeting. The unanimity of style andillustration makes the book read as a well produced textbook. Theline-drawings are, with few exceptions, of extremely high standard,and the book is very well produced, apart from the lack of an index.The contributors are all distinguished vascular surgeons, and apartfrom H. H. G. Eastcott and R. M. Greenhalgh (London) and H.-

614

Muller-Weifel (West Germany), they come from universityhospitals in the United States. They present the most recentdevelopments in operative techniques precisely and clearly. Thetopics covered include aortic aneurysm, cerebral revascularisation,visceral and renal arterial insufficiency, and lower leg bypasssurgery. There is also a section containing descriptions of novel.procedures for restoring venous valvular imcompetence; here someearly results would have been welcome.By including practically every major advance in vascular surgical

technique, this volume complements the standard textbooks. Allsurgeons dealing with vascular problems will find in it much tointerest them and much to help in the management of unpleasantcomplications, such as aorto-enteric fistula and graft infection,which occur from time to time even in the very best of hands. Everyvascular surgeon will want a copy for himself, and every hospitalwhere vascular surgery is practised should have one in the library.Department of Surgery,Lewisham Hospital, London DAVID NEGUS

Sports Fitness and Sports InjuriesEdited by Thomas Reilly, Liverpool Polytechnic. Faber and Faber. 1981.Pp. 293. 15.90, 9.45 (paperback).

Sports Injuries-The Unthwarted EpidemicEdited by P. F. Vinger, Emerson Hospital, Concord, Massachusetts,and E. F. Hoerner, Tufts University School of Medicine, Boston.Littleton, Massachusetts: PSG Publishing. 1981. Pp. 413.$49.50.

Two recent publications reflect the growing interest of the healthprofessions in sport, particularly the injuries related to sport. Thesetwo books cover very different aspects of the subject. Vinger andHoerner’s book is a comprehensive approach to the general study ofsports injury from different political, epidemiological, economic,and technical angles. Reilly’s book is an attempt to look at the morepractical aspects of the biology, science, and clinical medicine ofsports injuries.The distinguished list of American authors in Sports Injuries

indicates the strong interest shown at academic and governmentlevels in medical aspects of sport. The first section, on the monitor-ing of sports injuries, discusses data-gathering problems and looksat current reporting systems in America where separate reportingsystems are run through the U.S. Consumer Product Safety Com-mission and the National Athletic Injury Reporting System(NAIRS), which relies heavily on information from the athletictrainers.Problems of classification and epidemiology are well discussed,

and a fascinating section follows on methods of cost-benefit analysisof treatment of sports injuries. A memorable sentence reminds usthat "At the college and high school levels of competition, one mustbe guided by the concept that the primary goal of the player is toimprove the contents of the skull, not to damage them." The clinicalsections of the book are written from the standpoint of injuryanalysis and prevention, and do not pretend to be a descriptiveclinical text. Indeed, the adoption of such a critical attitude to injuryanalysis and prevention by all clinicians interested in sport shouldbe actively encouraged. This book is full of interesting ideas andstimuli for any serious students of the broader implications of sportsinjuries, though much of the content and discussion, particularlypolitical and economic, is naturally most relevant to the U.S.

Reilly’s book on Sports Fitness andSports Injuries is disappointing.the book starts with a section on aspects of fitness, which has anemphasis on psychology and engineering factors. This is followedby a section on training, and a section on the aetiology of injurywhich suffers from vagueness and tautology. Those on injuriesoccurring in team games, injuries in specific sports, and orthopaedicaspects of sports injuries leave a great deal to be desired. They are farfrom comprehensive, and many of the clinical sections betray a lackof both clinical experience and perspective - arguably inevitablewhen many clinical chapters are written by non-clinicians. Theediting is not firm enough, and there is sometimes an annoyingcombination of jargon and unclear English, for example in chapter4, on some psychological factors. Lack of clinical perspective is

evident in, for instance, the statement that a hamstring:quadricepsstrength ratio of 0 60 is recommended. Clinicians will find muchto criticise, for instance, the clinical aspects of Achilles injurypathology. Some of the sports-specific sections are frustratinglyincomplete, including the fundamental section on running. Thelack of hard facts coupled with plentiful empirical advice is

disappointing in a textbook. It is difficult to place this book. There iscertainly a need for such a volume, but a book whose title includesthe words "sports injuries" should have a much greater clinicalcontent. The next edition could do with double the number of factsand half the number of pages.

Hillingdon Athletes Clinic,Hillingdon Hospital P. N.SPERRYN

Neoplastic and Normal Cells in Culture

J. M. Vasiliev, Cancer Research Centre of U.S.S.R., Moscow, and MGelfand, Moscow State University. Cambridge: Cambridge UniversityPress. 1981. Pp. 372. L36.

THE behaviour of tumour cells in culture provides much insightinto the possible mechanisms of tumour proliferation and growthcontrol in vivo. To discuss this topic is an immense brief since itapplies to all disciplines of biology. Hence, except for the twointroductory chapters describing broadly some characteristics ofneoplastic cells and some mechanisms for their origin in culture, theauthors have restricted discussion to two main topics. First, theycompare the characteristics of normal cell morphology andmovement with those of neoplastically-transformed cells, culturedfibroblasts and epithelial cells being used as models. They describethe movement and interaction of whole cells. They also describe thetopography of the cell surface as seen under the scanning electronmicroscope, and the microcellular arrangement of microfilamentsand microtubules and the structure of cell-substratum points asdeduced by the use of transmission electron microscopy andimmunofluorescence techniques. Intracellular communication,perhaps mediated by microtubules, to coordinate movement of thecell, and inter-cell communication by formation of cell-cell contactsand chemical messengers, are discussed. The second main topiccovers growth-controlling mechanisms for normal cells in culture,such as anchorage dependence, density-dependent inhibition ofgrowth, and influence of extracellular growth factors, and theperturbation of these mechanisms in neoplastic cell-cultures.

Finally, there is a review of the material covered and discussion ofthe possible relevance of in vitro to in vivo findings.Because of the wide brief, it is not surprising that there is uneven

coverage of some of the material, much of which is descriptive innature. Formation of pseudopodia and attachment of cells to thesubstratum are dealt with in detail as one of the major determinantsof the behaviour of neoplastic cells, whereas the kinetics of growthof cultures are treated more concisely. Discussion of hypothesesarising from observations which cannot be interpreted definitely isuseful for indicating the areas where further research is needed, butin all sections these discussions could be condensed. The book iswell referenced, and many other reviews of the material are cited.Some previously unpublished work by the authors is presented.The book can be recommended as an introduction to the biology oftumours and provides a stimulating basis for those wishing topursue research in this subject.

Department of Haematology,University College Hospital, London PAMELA J. ROBERTS

New Editions

Nuclear Medicine Annual 1981.-Edited by Leonard M. Freeman. BeuYork. Raven Press. 1981. Pp. 347.$53.04.

- Clzmcal Electrocardiography.-2nd ed. By Ary Loms Goldberger andEmanuel Goldberger. London: Y.B. Medical Pubs. 1981. Pp. 307 f1225Accidents & Emergencies.-3rd ed. By R. H. Hardy. Oxford: Oxtor

University Press. 1981. Pp. 177.5.50.Year Book of Psychiatry tallied Mental Health 1981.-Edited by Damel T

Freedman. Arnold J. Friedhoff, Lawrence C. Kolb, Regional S. Loune, Johr.C. Nemiah, John Romano. London: Y. B. Medical Pubs. 1981. Pp. 373. i

615

THE LANCET

Oral Therapy for Acute Diarrhoea

SINCE the first controlled clinical trials of oral

rehydration therapy (ORT) in 1967,’ studies in adults,children, and infants have shown the efficacy of ORTin mild to severe acute diarrhoeal disease of various

aetiologies.1-1 (The work of the past fifteen years hasbeen reviewed in two recent papers.5,6) In manycountries diarrhoea is the major cause of morbidity andmortality in children under five, so the potential healthbenefits of oral therapy are profound. RAHMAN and co-workers,7 in Bangladesh, have shown an up to fivefoldreduction in diarrhoea case fatality with a home-basedORT programme. In India8 and Egypt9 similar ORTprogrammes have been associated with a halving ofdiarrhoea-related mortality. Although there may beargument over the magnitude of the gains, a decline inthe diarrhoea case fatality rate has been a consistentfinding when ORT has been accessible to the

community and properly used. Early therapy bymouth arrests and reverses the progression to severedehydration which might otherwise requireintravenous fluid. The World Health Organisation hasrecognised that oral therapy may be the single mostimportant step in the development of programmes tomanage diarrhoeal disease as well as a key to thereduction of infant and child morbidity and

mortality. 10,11 Questions, however, remain. What is thebest formula? How should it be packaged? What healthcare personnel are most appropriate for thedissemination of ORT? And what are the real effects ofORT on morbidity and mortality?

1. Nalin DR, Cash RA, Islam R, Molla M, Phillips RA. Oral maintenance therapy forcholera in adults Lancet 1968; ii: 370-73.

2 Pierce NF, Sack RB, Mitra R, Banwell J, Brigham K, Fedson D, Mondal A.Replacement of electrolyte and water losses in cholera by an oral glucose-electrolytesolution Ann Intern Med 1969; 70: 1173-81.

3 Mahalanabis D, Wallace CK, Kallen RJ, Mondal A, Pierce NF. Water and electrolytelosses due to cholera in infants and small children: a recovery balance studyPediatrics 1970: 45: 374-85.

4 Pizarro D, Posada G, Mata L, Nalin D, Mohs E. Oral rehydration of neonates withdehydrating diarrhoeas. Lancet 1979; ii: 1209-10.

5. Oral rehydration therapy (ORT) for childhood diarrhea. Population Reports 1980;November-December, series L, no. 2, Population Information Program, JohnsHopkins University.

6 Management of the diarrheal diseases at the community level. Committee onInternational Nutrition Programs. Washington, D.C.: National Academy ofSciences, National Academy Press, 1981

7 Rahman MM, Aziz KMS, Patwari Y, Munshi MH. Diarrhoeal mortality in twoBangladeshi villages with and without community-based oral rehydration therapyLancet 1979; ii: 809-12.

8 Kielmann AA, McCord C Home treatment of childhood diarrea in Punjab villages.Environmental Child Health 1977; 23: 197-201.

9 Mobarak MB, Hammamy MT, Gomaa AI, Abou-El-Saad S, Lotfi RK, Mazen I,Nagati A, Kielmann AA Diarrheal Disease Control Study. Final report on phase 1to USAID and WHO, April 1981. Strengthening Rural Health Delivery Project,Ministry of Health, Arab Republic of Egypt.

10 A manual for the treatment of acute diarrhoea. World Health Organisation, Programmefor Control of Diarrhoeal Diseases, Geneva- WHO/CDD/SER/80.2

11 Guidelines for the production of oral rehydration salts World Health Organization,Programme for Control of Diarrhoeal Diseases, Geneva: WHO/CDD/SER/80.3.

WHO has recommended a single oral rehydrationformula for the management of deficits in water, base,sodium, and potassium.’° The formula contains, inmmol per litre, 90 of sodium, 25 of potassium, 80 ofchloride, 30 of bicarbonate, and 110 of glucose. Mostexperts regard this as a physiologically sound mixturethat will ensure optimum salt and water absorption fordehydration ranging from imperceptible to severe. Toaccomplish the final concentration, two variables mustbe considered-the quantity of salts and the volume ofwater in which these salts are dissolved.

Stool sodiums are often less than 90 mmol/l, andsome workers maintain that the ORT should have asodium of 60 mmol/1 or less.12 With the exception ofrotavirus infections, where there are stool sodiumconcentrations of32±3 mmol/1,’3 the higher the stoolvolume the higher the sodium concentration and thegreater the sodium deficit. The existing formula,however, has proved satisfactory in clinical trials inmild to severe diarrhoea when the sodium concen-tration in stools was between 25 and 125 mmol/1.14 .This preparation has also shown itself safe irrespectiveof the aetiological agent. Hypernatraemia has veryseldom arisen. In fact, lowering the sodium to 60mmol/1 may entail a risk of prolonged hyponatraemia. 15One reason that the formula has proved successful isthat the patient always receives additional sodium-freewater.13,15 Free water may be given on demand or canbe given in a two-to-one regimen-that is, two parts ofORT followed by one part of free water in an

alternating pattern. Giving water on demand seems aseffective and is simpler. Additional sodium-free watermust not be directly added to the formula for thislowers the sugar concentration to less effective levels.

Feeding the infant with breast milk also reduces thefinal sodium concentration; human milk has only 2-3mmol of sodium per litre. In the treatment of rotavirusdiarrhoea, SACK et al. 13 showed that ORT with 90mmol sodium per litre entailed no risk of

hypernatraemia, even though the stool sodium did notexceed 35 mmol/1.

Stool potassium losses tend to be higher in childrenthan in adults and there can be substantial potassiumloss during diarrhoea. The recommendedconcentration of 25 mmol potassium per litre has beentolerated by all age groups; children have been treatedwith solutions containing 35 mmol/1 with no adverseeffects. Potassium losses may be partly compensatedwith foods such as citrus fruits, green coconut water,and bananas. Their potassium content is not, however,

12. Bart KJ, Finberg L. Single solution for oral therapy of diarrhoea. Lancet 1976, i.

633-34.

13. Sack DA, Chowdhury AMAK, Eusof A, Ali MA, Merson MH, Islam S, Black RE,Brown KH. Oral hydration in rotavirus diarrhoea: a double blind comparison ofsucrose with glucose electrolyte solution Lancet 1978; ii: 280-83

14 Hirschhorn N The treatment of acute diarrhea in children- an historical and

physiological perspective Am J Clin Nutr 1980; 33: 637-6315. Nalin DR, Harland E, Ramlal A, Swaby D, McDonald J, Gangarosa R, Levine M,

Akierman A, Antoine M, MacKenzie K, Johnson B. Comparison of low and highsodium and potassium content in oral rehydration solutions. J Pediat 1980, 97:848-53.