BACTERIAL ENDOCARDITIS AFTER ENDOSCOPY

BACTERIAL ENDOCARDITIS AFTER ENDOSCOPY

1083 OPIOID PEPTIDES AND STRESS HYPERGLYCAEMIA SiR,—Dr Moore and his colleagues (Sept. 13, p. 597) reported that reverses These findpostoperative hy...

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1083 OPIOID PEPTIDES AND STRESS HYPERGLYCAEMIA

SiR,—Dr Moore and his colleagues (Sept. 13, p.

597) reported that reverses These findpostoperative hyperglycaemia. buprenorphine ings support the notion that endogenous opioid peptides may be involved in the pathogenesis of stress hyperglycaemia.1 Endogenous opioid peptides are thought to mediate a number of the body’s responses to stress, such as prolactin secretion2and stress-induced 3 Also, &bgr;-endorphin is secreted by the pituitary gland during

feeding. stress.

We have evidence which provides a mechanism by which opioid may play a role in the development of stress hyperglycaemia. As pointed out by Moore and colleagues, morphine may raise the blood sugar, but in normals at clinically relevant doses the effect is minor. This may be due to a previously unrecognised insulin-stimulating effect of morphine, observed both in vivoand in vitro.5 Insulin released in response to morphine appears to counteract the potential hyperglycaemic effect of opiate-induced glucagon secretion 1,5,6 and adrenergic activity,8 thus maintaining

peptides

euglycaemia.

_

However, in the absence of this insulin response, as demonstrated in alloxan-produced insulin deficiency in dogs, hyperglycaemia does indeed occur, at doses of morphineor opioid peptide6 which do not cause any change in blood sugar in normal animals. This increase in blood glucose is accompanied by an opiate-induced increase of glucagon secretion. 1,6 The hyperglycaemia and cagonaemia are reversed by the opiate antagonist naloxone. Thus in situations where insulin secretion is diminished, such as diabetes mellitus or stress,8endogenous opioid peptides may, in part, be responsible for the development (or enhancement) ofhyperglycaemia mediated by glucagon and/or catecholamines. In selected situations, this hyperglycaemia may lend itself to reversal by opiate

hyperglu-

antagonists. Section of Endocrinology,

Department of Medicine, University of Chicago, Chicago, Illinois 60637, U.S.A.

The diagnosis was confirmed and a microaerophilic non-haemolytic streptococcus was cultured from the valvular vegetations. He made a good recovery and remains well four months later. It is likely that the streptococcus gained access to the circulation at the time of endoscopy; and as a result ofour experience we, like you, recommend antimicrobial prophylaxis for patients with valvular heart disease undergoing endoscopy until further information about the risk of endocarditis is available. W. RUMFELD Lincoln County Hospital, G. WALLACE Sewell Road, Lincoln LN2 5QY B. B. SCOTT

PERSISTENT FETAL CIRCULATION AND SUDDEN INFANT DEATH SYNDROME

SiR,—The hypothesis put forward by Dr Vessetinova-Jenkins (Oct. 18, p. 831) contains important and original suggestions which could explain some of the physiological findings of other workers who are monitoring breathing patterns and oxygen metabolism in the

born infant.

evidence for such an association is circumstantial and tenuous. It is based on the finding of prolonged apnoea in some infants who have already experienced an episode of so called "near-miss cot death". Apnoea, in these cases, has been presumed to be a primary cause of the collapse, but may equally represent the damaging effects of the near-miss episode on the respiratory control centres. Subsequent sudden death in infants who are known to have prolonged apnoea after a near-miss attack should not be regarded as unexplained (i.e., as

ELI IPP ARTHUR H. RUBENSTEIN

new

Throughout the paper, however, Dr Vesselinova-Jenkins conveys the impression that strong evidence exists relating sudden infant death syndrome (SIDS) or cot death to upper airway (obstructive) apnoea. We would, as we have elsewhere,’,- strongly argue that all

SIDS).

Direct evidence of a relationship between prolonged apnoea (whether it be central or obstructive in nature) and SIDS will only come from prospective studies of breathing patterns during infancy. D.P.S. is

a

British Heart Foundation senior research fellow.

Cardiothoracic Institute,

BACTERIAL ENDOCARDITIS AFTER ENDOSCOPY

SiR,—In your interesting editorial (Oct. 11, p. 782) on fibreoptic infections, your tentative recommendation is that patients with valvular heart disease undergoing upper gastrointestinal endoscopy should have antimicrobial prophylaxis. We should like to report a case of bacterial endocarditis diagnosed seven weeks after gastrointestinal endoscopy. On April 14 1980, an endoscopic examination with an Olympus GIF-K was carried out on a 60-year-old man with mitral stenosis (he had had a valvotomy in 1970) because of epigastric pain. A benign gastric ulcer was found and biopsy specimens taken. Four days later he has an inguinal hernia repair without apparent complication. On June 5 he was transferred from a psychiatric hospital to which he had been admitted a few days earlier with confusion and drowsiness. He was semi-comotose and had gross congestive heart failure, fever, and finger clubbing. Bacterial endocarditis was diagnosed and emergency mitral-valve replacement was done the following day. 1 Ipp E, Schusdziarra V, Unger RH. Morphine-induced hyperglycaemia:

Role of insulin

and glucagon. Endocrinology 1980; 107: 461-63. 2 Grandison L, Guidotti A. Regulation of prolactin release by endogenous opiates. Nature 1977; 270: 357-59. 3. Morley JE, Levine AS. Stress induced eating is mediated through endogenous opiates. Science 1980; 209: 1259-61. 4

Rossier J, French ED, Rivier C, Ling N, Guillemin R, Bloom FE. Footshock induced stress increases &bgr;-endorphin levels in blood but not the brain. Nature 1977; 260:

5

Ipp E, Dobbs R, Unger RH. Morphine and &bgr;-endorphin influence

618-20.

the secretion of the endocrine pancreas Nature 1978; 276: 190-91. 6 Ipp E, Dhorajiwala JM, Moossa AR, Rubenstein AH. Enkephalin stimulates insulin and glucagon in vivo, and accentuates hyperglycaemia in diabetic dogs. Clin Res 1980; 28: 396A 7 Bodo RC, Cotui FW, Benaglia AE. Studies on the mechanism of morphine hyperglycaemia. J Pharmacol Exp Ther 1937, 61: 48-57. 8. Woods SC, Porte D. Neural control of the endocrine pancreas. Physiol Rev 1974; 54: 596-619.

Brompton Hospital, London SW3 6HP

D. P. SAUTHALL

E. A. SHINEBOURNE

ASPIRATION CYTOLOGY IN PREOPERATIVE MANAGEMENT OF BREAST CANCER

SiR,—Mr Gardecki and his colleagues (Oct. 11, p. 790) gave an interesting analysis of the role of aspiration in the preoperative management of women with malignant disease of the breast, but I think that the conclusions drawn from the data

were not always justified. They claim that they had no difficulty with false-positive cytological results in their study of 121 patients with benign breast disease. They also quote a number of other small surveys which also claim a specificity of cytology reporting of 100%. These findings contrast with the results of all the larger studies of fine needle aspiration of the breast. 3-5 One study5 in which over 2000 patients with benign breast lumps were investigated, recorded false-positive reporting in 1.9%. As long as there is any risk of false positive reporting, it seems only sensible to take the precaution of confirming the cytodiagnosis by frozen section before proceeding to mastectomy.

DP, Richards JM, Brown DJ, Johnston PGB, de Swiet M, Shinebourne EA. 24-hour tape recording of ECG and respiration in the newborn infant with findings related to sudden death and unexplained brain damage in infancy. Arch Dis Child 1980, 55: 7-16. 2. Southall DP, Shinebourne EA. Sudden infant death syndrome and ventilatory control. Br Med J 1980; 281: 516 3. Franzen S, Zajicek J. Aspiration biopsy in diagnosis of palpable lesions of the breast: critical review of 3479 consecutive biopsies. Acta Radiol 1968: 7: 241-62. 4 Zajdela A, Ghossein NA, Pelleron JP, Ennuyer A. The value of aspiration cytology in the diagnosis of breast cancer, Experience at the Foundation Curie. Cancer 1975; 35: 499-506. 5. Kline TS, Joshi LP, Neal HS. Fine needle aspiration of the breast: diagnosis and pitfalls. Cancer 1979; 44: 1458-64. 1. Southall

.