364

the supine position, this compensatory mechanism will no

longer be available so that the patient’s hydration and nutritionmay be gravely prejudiced. At the same time, the risk ofpulmonary damage due to inhalation of oesophageal contentswill be increased.At the opposite end of the alimentary tract, a volvulus of either

the sigmoid or splenic loop of colon may give rise to intestinalobstruction. Gas accumulates in the convexity of the distendedloop which rises upwards. The site of the torsion is fixed bythe mesenteric attachment to the posterior abdominal wall. Ifthe patient is supine or even upright, the site of the torsion willusually be the lowest point. Any fluid in the loop will thereforecollect at this site and act as a seal to prevent the escape of gas.An enema administered in the supine position may force fluidinto the loop, but gas will be unable to escape. Turning thepatient prone will reverse the fluid-gas relationship, producinga more favourable situation for escape of gas from the distended

loop. Using these principles, a small number of patients withsubacute obstruction due to colonic volvulus have been success-

fully treated by the cautious administration of enemas withthe patient in the prone position (unpublished).

Liverpool. G. ANSELL.G. ANSELL.

ACUTE SALICYLATE POISONING

W. P. SWEETNAM.Royal Infirmary,Huddersfield.

SIR,-The articles on the management of salicylatepoisoning by Dr. Beveridge/ Dr. Ghose,2 and their

colleagues do not mention the straightforward method ofeliminating toxic amounts of aspirin, by exchange trans-fusion. This is a well-recognised and routine procedurefor removing a toxin-unconjugated bilirubin-from theblood of newborn babies and has been extended to

include many other poisons,3 some of which are non-dialysable.Exchange tranfusions seem particularly suitable for

smaller children. 90% of cases of poisoning in childrenoccur in the 1-4-year age-group, and these include abouttwo hundred cases of aspirin poisoning yearly. Theamount of blood required at this age is approximatelytwo to three litres-no more than is needed to prime manyhaemodialysis machines. The technique is relativelysimple, and the repeated and difficult biochemical andfluid control needed in forced diuresis is largely avoided.

FACTORS CONTROLLING RELEASE OF RENIN

FROM KIDNEY

JOHN SOPHIAN.

SIR,-Dr. Lowe (July 25) suggests that the juxta-glomerular apparatus is sensitive to pulsatile distension-the product of arteriolar pressure and renal compliance-and that the degree of this distension is inverselyresponsible for the release of renin, so that with a smallpulse and restricted distensibility the output of thishormone would be increased.

In the mechanism he indicates, limitation of distensililitycould be due inter alia to extracapsular restriction of the kidney,and it incriminates a large increase of intra-abdominal pressure,such as is produced by gross obesity, ascites, or pregnancy, asan important factor.

Paramore’s xtiological thesis of pre-eclampsia was based onthe pressure effects on the kidney brought about by the graviduterus. But a similar or even greater degree of pressureoccurred when large solid tumours of the uterus or ovarieswere present, without toxarmia supervening, and this fact washeld successfully against his thesis. In view of the increasedabdominal pressure present with these tumours, hypertension,according to Dr. Lowe’s thesis, should be an accompanyingclinical state, which is not so. (Neither is there any published1. Beveridge, G. W., Forshall, W., Munro, J. F., Owen, J. A., Weston,

I. A. G. Lancet, 1964, i, 1406.2. Ghose, R. R., Joekes, A. M. ibid. p. 1409.3. Sweetnam, W. P. J. forens. Sci. Soc. 1964, 4, 134.

report that has come to my notice, that the ascites of carci-nomatosis of the peritoneum is associated with hypertension.)The obstetrician cannot therefore accept the suggestion

that a large increase on intra-abdominal pressure is res-ponsible for renin production-a suggestion that could bemistakenly invoked as explaining the aetiology of pregnancynephropathy.

Worthing. JOHN SOPHIAN.

KLINEFELTER’S SYNDROME WITH ASTHMA

A. J. M. L. BOMERS-MARRES.Dennenoord

Psychiatric Hospital,Zuidlaren, The Netherlands.

SIR,-I read with great interest the letter of Dr. Dalyand Dr. Rickards (June 27).

In an investigation for sex-chromatin in 70 mentally deficientmale patients in a psychiatric hospital, 1 patient turned out tobe sex-chromatin positive. He had had severe asthma from hisyouth onward (none of the other 69 patients has asthma).The patient is unmarried and 53 years of age. He has been

treated in this hospital for 11 years for a mental disorder. Hisheight is 168 cm.-pubis to sole 85 cm. Hypogonadism andgynaecomastia are present. Facial hair growth is slight, andaxillary and pubic hair growth are less than normal. Urinarygonadotrophin excretion is raised.

Here, then, is another case showing the combination ofKlinefelter’s syndrome and asthma.

SCREENING TEST FOR CHLOROQUINERETINOPATHY

SIR,-Our paper 1 had only one purpose-to describe asimplified technique of extra-oculography using an

E.C.G. machine to encourage screening and serialE.O.G. testing to become routine We do not claim tohave discussed the complex problems surrounding thesubject in the hundred words of our introduction.Nevertheless Dr. Henkind’s disagreement (July 4) withthis part of the paper can be answered briefly.Whether the frequency of chloroquine retinopathy " may be

as high as 3% " or " exceeding 3% " (as Dr. Henkind writes)is unimportant; the truth is that chloroquine can blind asignificant number of patients who take the drug in the higherdosage used in disorders of the skin and connective tissue-butprobably not the " thousands, perhaps millions " that hementions who take this and similar drugs as treatment in lowerdoses for malaria. Hence we did not advocate serial E.O.G.

testing for these patients. Commenting on the paper of Ardenet al.,2 Gouras and Gunkel,s whom we quoted, remarked thatsubjects sensitive to chloroquine may have transient E.O.G.

changes detectable at an asymptomatic and reversible stage ofretinal damage, while they are taking the drug, but theyexplained their own negative results because, in their series, thepatients had discontinued chloroquine for at least a year beforethe tests (therefore the opinions of Gouras and Ginkel arerelevant even if they are not those held by Dr. Henkind). Wehad hoped that our own simplified technique would allow serialE.O.G. testing while patients were taking the drug to become amore widespread investigation.We are pleased to have our attention drawn to Dr. Henkind’s

paper describing the ophthalmoscopic appearances of the

retinopathy.4 It was not cited, because it was not publishedwhen our article was written. We used the term " extra-oculogram

" rather than " electro-oculogram " because it hasbeen used by authorities on the subject in this country,2 but wehave no objection to

"

electro-oculogram ". We wonderwhether the prefix" extra " implies that the electrodes areapplied away from the eyeball itself, a simple and more com-fortable procedure, unlike the electroretinogram (E.R.G.) inwhich they are usually applied to the eyeball ?1. Copeman, P. W. M., Cowell, T. K., Dallas, N. L. Lancet, 1964, i, 1369.2. Arden, G. B., Friedmann, A., Kolb, H. L. ibid. 1962, i, 1164.3. Gouras, P., Gunkel, R. D. Arch. Ophthal. 1963, 70, 629.4. Henkind, P., Carr, R., Siegel, I. ibid. 1964, 71, 157.