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antibody and before they develop their own natural antibodies against the capsular antigen that is, between the ages of about 3 months and 5 years-and oral vaccination at the age of 3-6 months might overcome this gap in immunity. The strains of E. coli used have shown no evidence of enteropathogenicity, nor do they appear to be invasive. They are not entirely avirulent-they may be able to cause urinary-tract infection, for examplebut they do not appear to be any different in this respect from many other strains of E. coli that are to be found in large numbers in the normal human intestine.9 The investigators have not yet tried to immunise babies in this way; but the procedure has been shown to work in baby rabbits,and E. coli strains have been safely fed to newborn babies by workers in Czechoslovakia, who also showed that an antibody response developed when the intestine was colonised.13 Since babies are bound to be colonised by similar organisms quite naturally, the process should be safe provided the strains do not cause diarrhoea or other illness. The incidence of Haemophilus meningitis can be estimated only roughly. About 1500 cases of acute meningitis are notified in England and Wales to the Registrar General each year, and returns to the Public Health Laboratory Service suggest that about 20-25% of laboratory-diagnosed cases are due to H. influenzæ.14,15 If it is accepted that meningitis is undernotified by about 50%, there may be 800 cases each year in England and Wales. Since the disease mostly affects children under 5 years of age, perhaps 1 child in 1000 is liable to contract the disease before the 5th birthday. The mortality-rate may be as high as 10%, and the incidence of sequelse, which can include impaired intelligence, behaviour disorders, or hydrocephalus, has been reported to be 30% in the U.S.A.16 and 22% in Sweden.l’ Thus Haemophilus meningitis, though not common, is a serious illness, and the use of a vaccine given simply by mouth might be worth while provided it could be shown to be both safe and protective. Proof of safety may be obtainable by careful clinical trials, first in small groups and later in larger; but efficacy may be hard to establish since the disease has such a low incidence. Babies may not respond to the vaccination so well as immunologically mature adults,18 most of whom already possess some antibody against the shared antigen, and susceptibility to Haemophilus infection may be influenced by factors other than circulating antibody. 19. 20But the exploitation of what is probably the natural process by which infants become immune to this serious infection might prove a valuable and economical approach to infectious-disease control, with possibilities for other pathogens-meningococci and pneumococci, for example-that share antigens with bacteria of the commensal flora. 13. Lodinova, R., Jouja, V., Lanc, A. J. Bact. 1967, 93, 797. 14. P.H.L.S. Br. med. J. 1974, i, 453. 15. P.H.L.S. ibid. 1973, i, 623. 16. Sell, S. H. W., Merrill, R. E., Doyne, E. O., Zimsky, E. P., Jr. Pediatrics, Springfield, 1972, 49, 206. 17. Jonsson, M., Alvin, A. Scand. J. infect. Dis. 1971, 3, 141. 18. Smith, D. H., Peter, G., Ingram, D. L., Harding, A. L., Anderson, P. Pediatrics, Springfield, 1973, 52, 637. 19. Feigin, R. D., Richmond, D., Hosler, M. W., Shackelford, P. G. Am. J. med. Sci. 1971, 262, 338. 20. Lancet, 1971, ii, 914.
INTRAVENOUS UROGRAPHY IN HYPERTENSION THE morbidity and mortality associated with a high blood-pressure are a considerable incentive to clinicians to try to cure the hypertension by finding a surgically correctable abnormality of the renal, vascular, or endocrine system. Today’s drugs, however, can now control the blood-pressure of a large proportion of hypertensive patients and so the more elaborate investigations, such as renal arteriography or divided renal-function tests, are reserved for the occasional patient. Intravenous urography, however, is normally recommended as a routine investigation for those who 1 may need treatment. A greater awareness of hypertension and organised screening programmes 2-4are leading to the detection of an increasing number of patients with mild hypertension. Can we justify the cost and the inconvenience and risk to the patient of intravenous urography in all these cases ? Atkinson and Kellett5 made a retrospective analysis of the value of intravenous urography in 952 patients attending the Glasgow blood-pressure clinic. Although 120 (17-6%) renal abnormalities were demonstrated, these led to a change in patient management in only 9 cases (0-9%). A few of their patients, however, had been followed up for as little as four months, and so it is reassuring to see their results confirmed by Dr Bailey and others (on p. 57 this week). They followed up a group of patients for at least three years. In 80 patients, urography revealed 15 renal abnormalities (19%), but in only 1 was patient management changed by unexpected urographic findings. This patient underwent nephrectomy for unilateral pyelonephritis, but this did not lead to a permanent cure of her hypertension. Can 80 urograms be justified to pick up 1 patient ? An attractive proposal is to limit urography to selected patients in whom the yield is likely to be higher. Kreel et al.’studying a large series of mostly normotensive patients investigated by urography, proposed that this investigation should not be ordered until the results of simple investigations, such as urine examination and culture, have been studied; and Bailey et al. suggest that the indications in hypertension should be the same as in the normotensive population. The Glasgow group,5 however, found that this policy would miss a small number of significant lesions in younger patients, and, while agreeing with these indications in the older patients, suggest that urography remain routine in patients up to the age of 40. Can these results be extrapolated to other investigations for hypertension ? Is there now ever a place for admitting a patient with other than the most severe hypertension to the ward for investigation ? Answers to these questions are urgently needed, especially since here may lie an opportunity for large financial
savings. 1. Pickering, G. W. High Blood Pressure. London, 1968. 2. Tudor Hart, J. Lancet, 1970, ii, 223. 3. Lovell, R. R., Prineas, R. J. Int. J. Epidemiol. 1974, 3, 25. 4. Hawthorne, V. M., Greaves, D. A., Beevers, D. G. Br. med. J. 1974, iii, 600. 5. Atkinson, A. B., Kellett, R. J.Jl R. Coll. Phycns Lond. 1974, 8, 175. 6. Kreel, L., Elton, A., Habershon, R., Mason, A. M. S., Meade, T. W. Br. med. J. 1974, iv, 31.
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antibody and before they develop their own natural antibodies against the capsular antigen that is, between the ages of about 3 months and 5 years-and oral vaccination at the age of 3-6 months might overcome this gap in immunity. The strains of E. coli used have shown no evidence of enteropathogenicity, nor do they appear to be invasive. They are not entirely avirulent-they may be able to cause urinary-tract infection, for examplebut they do not appear to be any different in this respect from many other strains of E. coli that are to be found in large numbers in the normal human intestine.9 The investigators have not yet tried to immunise babies in this way; but the procedure has been shown to work in baby rabbits,and E. coli strains have been safely fed to newborn babies by workers in Czechoslovakia, who also showed that an antibody response developed when the intestine was colonised.13 Since babies are bound to be colonised by similar organisms quite naturally, the process should be safe provided the strains do not cause diarrhoea or other illness. The incidence of Haemophilus meningitis can be estimated only roughly. About 1500 cases of acute meningitis are notified in England and Wales to the Registrar General each year, and returns to the Public Health Laboratory Service suggest that about 20-25% of laboratory-diagnosed cases are due to H. influenzæ.14,15 If it is accepted that meningitis is undernotified by about 50%, there may be 800 cases each year in England and Wales. Since the disease mostly affects children under 5 years of age, perhaps 1 child in 1000 is liable to contract the disease before the 5th birthday. The mortality-rate may be as high as 10%, and the incidence of sequelse, which can include impaired intelligence, behaviour disorders, or hydrocephalus, has been reported to be 30% in the U.S.A.16 and 22% in Sweden.l’ Thus Haemophilus meningitis, though not common, is a serious illness, and the use of a vaccine given simply by mouth might be worth while provided it could be shown to be both safe and protective. Proof of safety may be obtainable by careful clinical trials, first in small groups and later in larger; but efficacy may be hard to establish since the disease has such a low incidence. Babies may not respond to the vaccination so well as immunologically mature adults,18 most of whom already possess some antibody against the shared antigen, and susceptibility to Haemophilus infection may be influenced by factors other than circulating antibody. 19. 20But the exploitation of what is probably the natural process by which infants become immune to this serious infection might prove a valuable and economical approach to infectious-disease control, with possibilities for other pathogens-meningococci and pneumococci, for example-that share antigens with bacteria of the commensal flora. 13. Lodinova, R., Jouja, V., Lanc, A. J. Bact. 1967, 93, 797. 14. P.H.L.S. Br. med. J. 1974, i, 453. 15. P.H.L.S. ibid. 1973, i, 623. 16. Sell, S. H. W., Merrill, R. E., Doyne, E. O., Zimsky, E. P., Jr. Pediatrics, Springfield, 1972, 49, 206. 17. Jonsson, M., Alvin, A. Scand. J. infect. Dis. 1971, 3, 141. 18. Smith, D. H., Peter, G., Ingram, D. L., Harding, A. L., Anderson, P. Pediatrics, Springfield, 1973, 52, 637. 19. Feigin, R. D., Richmond, D., Hosler, M. W., Shackelford, P. G. Am. J. med. Sci. 1971, 262, 338. 20. Lancet, 1971, ii, 914.
INTRAVENOUS UROGRAPHY IN HYPERTENSION THE morbidity and mortality associated with a high blood-pressure are a considerable incentive to clinicians to try to cure the hypertension by finding a surgically correctable abnormality of the renal, vascular, or endocrine system. Today’s drugs, however, can now control the blood-pressure of a large proportion of hypertensive patients and so the more elaborate investigations, such as renal arteriography or divided renal-function tests, are reserved for the occasional patient. Intravenous urography, however, is normally recommended as a routine investigation for those who 1 may need treatment. A greater awareness of hypertension and organised screening programmes 2-4are leading to the detection of an increasing number of patients with mild hypertension. Can we justify the cost and the inconvenience and risk to the patient of intravenous urography in all these cases ? Atkinson and Kellett5 made a retrospective analysis of the value of intravenous urography in 952 patients attending the Glasgow blood-pressure clinic. Although 120 (17-6%) renal abnormalities were demonstrated, these led to a change in patient management in only 9 cases (0-9%). A few of their patients, however, had been followed up for as little as four months, and so it is reassuring to see their results confirmed by Dr Bailey and others (on p. 57 this week). They followed up a group of patients for at least three years. In 80 patients, urography revealed 15 renal abnormalities (19%), but in only 1 was patient management changed by unexpected urographic findings. This patient underwent nephrectomy for unilateral pyelonephritis, but this did not lead to a permanent cure of her hypertension. Can 80 urograms be justified to pick up 1 patient ? An attractive proposal is to limit urography to selected patients in whom the yield is likely to be higher. Kreel et al.’studying a large series of mostly normotensive patients investigated by urography, proposed that this investigation should not be ordered until the results of simple investigations, such as urine examination and culture, have been studied; and Bailey et al. suggest that the indications in hypertension should be the same as in the normotensive population. The Glasgow group,5 however, found that this policy would miss a small number of significant lesions in younger patients, and, while agreeing with these indications in the older patients, suggest that urography remain routine in patients up to the age of 40. Can these results be extrapolated to other investigations for hypertension ? Is there now ever a place for admitting a patient with other than the most severe hypertension to the ward for investigation ? Answers to these questions are urgently needed, especially since here may lie an opportunity for large financial
savings. 1. Pickering, G. W. High Blood Pressure. London, 1968. 2. Tudor Hart, J. Lancet, 1970, ii, 223. 3. Lovell, R. R., Prineas, R. J. Int. J. Epidemiol. 1974, 3, 25. 4. Hawthorne, V. M., Greaves, D. A., Beevers, D. G. Br. med. J. 1974, iii, 600. 5. Atkinson, A. B., Kellett, R. J.Jl R. Coll. Phycns Lond. 1974, 8, 175. 6. Kreel, L., Elton, A., Habershon, R., Mason, A. M. S., Meade, T. W. Br. med. J. 1974, iv, 31.
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