491 is essential to determine the relative importance of differxtiological agents in acute diarrhoea in children in developmg countries, since appropriate rehydration measures may depend on the mechanism of diarrhoea! fluid-loss. E.T.E.C. causes fluid-loss through a mechanism similar td Vibrio cholerœ, involving elevated levels of adenylate cyclase in the enterocyte. 14 Glucose-mediated sodium absorption is intact, and this explains the wide success of oral glucose/electrolyte
It
ent
solution in the treatment of cholera and related diarrhoea. There is evidence that the mechanism of fluid-loss in viral diarrhoea may be quite different. Studies in gnotobiotic piglets infected with transmissible gastroenteritis virus’S (a suggested model for human viral diarrhœa16) have demonstrated an intact adenylate-cyclase system and a defect in jejunal glucosemediated sodium transport. A similar defect in infection with duovirus could render oral glucose/electrolyte solutions ineffective. Further clarification of underlying mechanisms of fluid-loss is needed, along with a clearer understanding of the xtiology and epidemiology of diarrhoea. Department of Child Health, Faculty of Medicine, Gadjah Mada University, Yogyakarta, Indonesia School of Agriculture, La Trobe University,
Bundoora, Victoria, Australia, 3083
Department of Gastroenterology, Royal Children’s Hospital,
TELUK SEBODO YATI SOENARTO JON E. ROHDE N. B. R.
J. RYAN J. TAYLOR J. K. LUKE
Parkville, Victoria, Australia, 3052
R. F. BISHOP G. L. BARNES
Department of Microbiology, University of Melbourne, Parkville, Victoria,
I. H. HOLMES
Australia, 3052
B. J. RUCK
DISINFECTION OF CYSTOSCOPES BY LOW-TEMPERATURE STEAM
ing organisms are so rare after cystoscopy that disinfection is all that is required. Since this can be achieved by low-temperature steam alone and the addition of a formaldehyde cycle does not guarantee sterilisation, a simpler, and presumably cheaper, machine should suffice. Microbiology Laboratories, Raigmore Hospital, Inverness IV2
VACCINATION AGAINST WHOOPING-COUGH
SIR,-We should like to point out two errors in the article by Dr Malleson and Dr Bennett (Jan. 29, p. 237). The pertussis immunisation-rates 1964-71 cited for Derbyshire are, in fact, those for the former Derby county borough. During this period rates in the administrative county were lower than the rates in Derby (e.g., 1971 Derby 80%, Derbyshire 68%). Secondly, the immunisation schedules cited are again those for Derby. Following Department of Health guidance in 1968 relating to immunisation schedules, the Derbyshire county health department in 1970 adopted the schedule of starting the primary immunisations at six months of age. These two errors of fact are relevant since 50% of total admissions to the Derbyshire Children’s Hospital are from the former Derby borough and 50% are from the county. The lower acceptance-rate for pertussis immunisation for half of the hospital’s catchment area would lower the average acceptance rate (75%). This would have some effect on the significance tests. We consider that the second point, concerning the age at which immunisations were started for children admitted from the county, could have a greater affect on the significance tests, because it would change the size of the sample. In table I the number who were too young for immunisation would increase, with a corresponding decrease in the number eligible. Although these points may not alter the conclusions reached in the paper, they will undoubtedly alter the figures shown in table n. P. K. SYLVESTER
SIR,-There can be little doubt that low-temperature steam will disinfect cystoscopes. Ten minutes exposure at 730C without formaldehyde was lethal to vegetative bacteria in our tests, as it was in those done by Dr Ayliffe and his colleagues (Jan.
Derbyshire Area Health Authority, Derby DE1 2GA
29, p. 256). Unfortunately, however,
error
the manufacturer’s advertising literature claims that the ’Miniclave 80’ will facilitate the "safe sterilisation of cystoscopes". The use of the term sterilisation implies the destruction of all microbial life, including bacterial spores. The tests performed by Dr Ayliffe and his colleagues do not seem to substantiate this claim since some of their test spores survived twice the length of exposure and three times the concentration of formalin recommended by the manufacturer. The relevance of both the Alder and the Line & Pickerill test pieces is uncertain. In our tests we used cystoscopes. The narrow-bore catheter channel is difficult to clean and cannot be guaranteed free of protein. The spores used in the test were, therefore, soaked in blood and pus and the distal ends of the channels were blocked. Under these conditions the ’Miniclave 80’ (factory pre-set for 20 min exposure at 73°C with 3 ml of formaldehyde) invariably failed to kill the spores. Even with higher concentrations and longer exposure up to 60 min at 73°C with 9 ml of formaldehyde sterilisation was only achieved in 18/52 (35%) of the tests. It may well be that urinary-tract infections with spore-bear14 New Engl J Med 1975, 292, 969. 15 McClung, H J., Butler, D. G., Kerzner, B., Gall, D. G., Hamilton, J. R. Gastroenterology, 1976, 70, 1091. 16 Hamilton, J. R., Gall, D. G., Kerzner, B., Butler, D. G., Middleton, P. J. Pediat Clins N Am 1975, 22, 747
A. B. WHITE
3UJ
JOHN BEAL D. HARRISON
We apologise to Dr Malleson for the introduction of an into his letter last week (p. 419). The first sentence in the third paragraph should read: "... we grouped partially and fully immunised children together as ’immunised’."—ED.L.
***
ACUTE MOUNTAIN SICKNESS
SIR,-Since the publication of our paper’
we
have observed
of peripheral cedema in hikers seen at Pheriche 4243 m, on the approach route to Mount Everest, during a ten-day period in the late autumn of 1976. 7 were females aged 28-54 (mean age 45) and 3 males (ages 31, 38, and 63). As Sheridan and Sheridan2 have described, 7 showed periorbital and facial oedema, very gross in 2; 7 showed oedema of the hands alone, and 2 showed severe leg oedema. There was no relationship between the oedema and the menstrual cycle or the taking of oral contraceptives- (2 patients) in this group of 7 women. 2 of the worst affected were postmenopausal and not on replace-
10
cases
ment
therapy.
We have always considered such peripheral oedema to be common and of no real significance. What is striking about this group of 10, however, is that 5 of the 7 women and all 3 men had loud pulmonary râles, while 1 of the 2 women without rales had been treated with diuretics for severe breathless1. Hackett, P., Rennie, I. D., Levine, H. D. Lancet, 2. Sheridan, J. W, Sheridan, R. ibid. 1970,i, 242.
1976, ii, 1149.
It
ent
solution in the treatment of cholera and related diarrhoea. There is evidence that the mechanism of fluid-loss in viral diarrhoea may be quite different. Studies in gnotobiotic piglets infected with transmissible gastroenteritis virus’S (a suggested model for human viral diarrhœa16) have demonstrated an intact adenylate-cyclase system and a defect in jejunal glucosemediated sodium transport. A similar defect in infection with duovirus could render oral glucose/electrolyte solutions ineffective. Further clarification of underlying mechanisms of fluid-loss is needed, along with a clearer understanding of the xtiology and epidemiology of diarrhoea. Department of Child Health, Faculty of Medicine, Gadjah Mada University, Yogyakarta, Indonesia School of Agriculture, La Trobe University,
Bundoora, Victoria, Australia, 3083
Department of Gastroenterology, Royal Children’s Hospital,
TELUK SEBODO YATI SOENARTO JON E. ROHDE N. B. R.
J. RYAN J. TAYLOR J. K. LUKE
Parkville, Victoria, Australia, 3052
R. F. BISHOP G. L. BARNES
Department of Microbiology, University of Melbourne, Parkville, Victoria,
I. H. HOLMES
Australia, 3052
B. J. RUCK
DISINFECTION OF CYSTOSCOPES BY LOW-TEMPERATURE STEAM
ing organisms are so rare after cystoscopy that disinfection is all that is required. Since this can be achieved by low-temperature steam alone and the addition of a formaldehyde cycle does not guarantee sterilisation, a simpler, and presumably cheaper, machine should suffice. Microbiology Laboratories, Raigmore Hospital, Inverness IV2
VACCINATION AGAINST WHOOPING-COUGH
SIR,-We should like to point out two errors in the article by Dr Malleson and Dr Bennett (Jan. 29, p. 237). The pertussis immunisation-rates 1964-71 cited for Derbyshire are, in fact, those for the former Derby county borough. During this period rates in the administrative county were lower than the rates in Derby (e.g., 1971 Derby 80%, Derbyshire 68%). Secondly, the immunisation schedules cited are again those for Derby. Following Department of Health guidance in 1968 relating to immunisation schedules, the Derbyshire county health department in 1970 adopted the schedule of starting the primary immunisations at six months of age. These two errors of fact are relevant since 50% of total admissions to the Derbyshire Children’s Hospital are from the former Derby borough and 50% are from the county. The lower acceptance-rate for pertussis immunisation for half of the hospital’s catchment area would lower the average acceptance rate (75%). This would have some effect on the significance tests. We consider that the second point, concerning the age at which immunisations were started for children admitted from the county, could have a greater affect on the significance tests, because it would change the size of the sample. In table I the number who were too young for immunisation would increase, with a corresponding decrease in the number eligible. Although these points may not alter the conclusions reached in the paper, they will undoubtedly alter the figures shown in table n. P. K. SYLVESTER
SIR,-There can be little doubt that low-temperature steam will disinfect cystoscopes. Ten minutes exposure at 730C without formaldehyde was lethal to vegetative bacteria in our tests, as it was in those done by Dr Ayliffe and his colleagues (Jan.
Derbyshire Area Health Authority, Derby DE1 2GA
29, p. 256). Unfortunately, however,
error
the manufacturer’s advertising literature claims that the ’Miniclave 80’ will facilitate the "safe sterilisation of cystoscopes". The use of the term sterilisation implies the destruction of all microbial life, including bacterial spores. The tests performed by Dr Ayliffe and his colleagues do not seem to substantiate this claim since some of their test spores survived twice the length of exposure and three times the concentration of formalin recommended by the manufacturer. The relevance of both the Alder and the Line & Pickerill test pieces is uncertain. In our tests we used cystoscopes. The narrow-bore catheter channel is difficult to clean and cannot be guaranteed free of protein. The spores used in the test were, therefore, soaked in blood and pus and the distal ends of the channels were blocked. Under these conditions the ’Miniclave 80’ (factory pre-set for 20 min exposure at 73°C with 3 ml of formaldehyde) invariably failed to kill the spores. Even with higher concentrations and longer exposure up to 60 min at 73°C with 9 ml of formaldehyde sterilisation was only achieved in 18/52 (35%) of the tests. It may well be that urinary-tract infections with spore-bear14 New Engl J Med 1975, 292, 969. 15 McClung, H J., Butler, D. G., Kerzner, B., Gall, D. G., Hamilton, J. R. Gastroenterology, 1976, 70, 1091. 16 Hamilton, J. R., Gall, D. G., Kerzner, B., Butler, D. G., Middleton, P. J. Pediat Clins N Am 1975, 22, 747
A. B. WHITE
3UJ
JOHN BEAL D. HARRISON
We apologise to Dr Malleson for the introduction of an into his letter last week (p. 419). The first sentence in the third paragraph should read: "... we grouped partially and fully immunised children together as ’immunised’."—ED.L.
***
ACUTE MOUNTAIN SICKNESS
SIR,-Since the publication of our paper’
we
have observed
of peripheral cedema in hikers seen at Pheriche 4243 m, on the approach route to Mount Everest, during a ten-day period in the late autumn of 1976. 7 were females aged 28-54 (mean age 45) and 3 males (ages 31, 38, and 63). As Sheridan and Sheridan2 have described, 7 showed periorbital and facial oedema, very gross in 2; 7 showed oedema of the hands alone, and 2 showed severe leg oedema. There was no relationship between the oedema and the menstrual cycle or the taking of oral contraceptives- (2 patients) in this group of 7 women. 2 of the worst affected were postmenopausal and not on replace-
10
cases
ment
therapy.
We have always considered such peripheral oedema to be common and of no real significance. What is striking about this group of 10, however, is that 5 of the 7 women and all 3 men had loud pulmonary râles, while 1 of the 2 women without rales had been treated with diuretics for severe breathless1. Hackett, P., Rennie, I. D., Levine, H. D. Lancet, 2. Sheridan, J. W, Sheridan, R. ibid. 1970,i, 242.
1976, ii, 1149.
