- Email: [email protected]
WHICH ANTIBIOTIC FOR BACTERIA WITH INDUCIBLE CLASS I β-LACTAMASE?
102 In summary,
the artificial environment of
respiration
4.
chamber, the two studies show that EE obtained in the calorimeter bears a relationship with that found in free-living conditions since
5.
despite
a
69% (r2) of the variance in EE in free-living people could be accounted for by variation in EE measured in the calorimeter. This is due to the fact that in free-living situations a large part of EE is accounted for by resting and spontaneous energy expenditure, a condition typical of our sedentary society and the one encountered in the whole body calorimeter. Institute
of Physiology,
Medical
School,
Y. SCHUTZ
University of Lausanne, CH-1005 Lausanne, Switzerland
E. JÉQUIER
AM, Coward WA, Davies HL, et al. Unexpectedly low levels of energy expenditure in healthy women. Lancet 1985; i. 1419-22 2. Dauncey MJ, James WPT. Assessment of the heart rate method for determining energy expenditure in man, using a whole body calorimeter. Br J Nutr 1979; 42: 1-13. 3. Schutz Y, Dusmet M, Bessard T, et al. Estimate of 24 hour energy expenditure in man by continuous heart rate monitoring. In Proceedings of 4th Europ Nutrition Conference. The Hague. Voorlichtingsbureau voor de voeding, 1985: 199. 1. Prentice
EQUATION IN PREGNANCY and colleagues (Oct 12, p 823) raise
ENERGY
SiR.—Dr Durnin
a
very
pertinent question about energy requirement in pregnancy. In 1971 we reported on the energy cost of rest and some activities in 42 pregnant women compared with non-pregnant women and concluded that, though the energy cost increased with the advance of pregnancy, pregnant women performed their activities more economically. Our data’ are similar to those of Durnin et al. We measured the energy cost of rest and different activities in 11 women in the second and in the third trimesters. The energy cost of rest increased in the third trimester by about 9% and those of activities by 12-17%, when expressed per minute. However, there was not much increase in later pregnancy when the energy cost was expressed per kg/h: indeed there was a 4% decrease in resting metabolism. In a second study we measured daily energy intake and expenditure in 24 pregnant women over seven days to assess the
energy balance in pregnancy.2We observed an average positive balance of about 200 kcal per day (including excretion wastes which were not measured) with an average gestation period of 30 weeks and body weight of 54 - 5 kg. The surplus intake would be much less if the excretory loss of energy was considered. However, in all these women there was a great deal of inter-individual variation both of energy cost and intake. There were considerable differences in the energy cost of rest and activities between obese and thin This children4 and between active and sedentary suggests that energy cost is greatly influenced by body composition, such as proportions of body fat and muscle bulk. Inter-individual differences were much less when the energy cost was expressed per kg of calculated lean body mass.It is probably important to interpret the energy requirements or expenditure in pregnancy in the context of the much altered body composition found during pregnancy. In all our studies we found that the energy costs of rest and work in the tropics man are much less than those of Western man, even when body weight is taken into account.l,3-7 Although the evidence so far available suggests that the recommended energy requirement (FAO/WHO) for pregnant women is far in excess of the real need, far more experiments should be done before a conclusion is drawn.
6 7
Banerjee B, Saha N. Energy cost of some common physical activities of Chinese school boys. Ann Nutr Metab 1982; 26: 360-66. Banerjee B, Saha N. Energy cost of some common daily activities of active tropical male and female subjects. J Appl Physiol 1970, 29: 200-03. Saha N, Tan PY, Banerjee B. Energy balance study in Singapore medical students. Ann Nutr Metab 1985; 29: 216-22. Saha N. On the critical-fat hypothesis Curr Anthropol 1985; 26: 666.
WHICH ANTIBIOTIC FOR BACTERIA WITH INDUCIBLE CLASS I &bgr;-LACTAMASE?
SIR,-In our letter (Sept 21, p 673) commented on by Dr Shannon and colleagues (Nov 2, p 1016) we suggested the use of a combination of piperacillin or azlocillin/mezlocillin plus an aminoglycoside (rather than a third-generation cephalosporin) in the treatment of infections with gram-negative bacteria (Pseudomonus aeruginosa and Enterobacteriaceae) shown to be inducible for class I P-lactamases by the disc induction technique. The rationale behind this suggestion is that therapeutic failures due to the emergence of stably derepressed mutants (producing significant amounts of class I (3-lastamases) are less likely to occur following therapy with these penicillins than with the thirdgeneration cephalosporins (C. C. Sanders, personal communication). Indeed, therapeutic failures due to this mechanism of resistance were seldom seen before the clinical use of thirdgeneration cephalosporins.Piperacillin has low inducer activity in vitro for class I (3-lactamase production in Enterobacter and indolepositive Proteus compared with other &bgr;-lactams, including
carbenicillin.2-4
recommend the use of these penicillins in the with strains already stably derepressed. In these circumstances, we would look to newer chemotherapeutic agents unaffected by class I &bgr;-lactamases, such as the recently developed quinolones and thienamycins.
We did
not
treatment of infections
Department of Microbiology, Queen Mary’s Hospital, London SW15 5PN
M. J. WEINBREN R. M. PERINPANAYAGAM
LJU, Wise R. Newer mechanisms of resistance p lactam antibiotics in Grambacteria. J Antimicrob Chemother 1985; 16: 279-84. Yotsuji A, Inoue M, Mitsuhashi S. Induction of &bgr;-lactasase by various &bgr;-lactam anti-biotics in Enterobacter cloacae Antimicrob Ag Chemother 1980; 18:
1 Piddock
negative 2. Minami S,
382-85. Minami S, Araki Y, Inoue M, Mitsuhashi S. Inducer activity of &bgr;-lactam antibiotics for the &bgr;-lactamases of Proteus rettgeri and Proteus vulgaris. J Antibiotics 1982; 35: 1590-93 4 Minami S, Matsubara N, Yotsuji A, et al Induction of cephalosporinase production by various penicillins in enterobacteriaceae. J Antibiotics 1983; 36: 3187-95. 3
Yotsuji A,
adult.rowing
Department of Physiology, Faculty of Medicine, National University of Singapore, Singapore 0511
N. SAHA
1 Banerjee B, Khew KS, Saha N. A comparative study of energy expenditure in some common daily activities of non-pregnant and pregnant Chinese, Malay and Indian women J Obstet Gynae Br Commonw 1971; 78: 113-16. 2 Banerjee B, Saha N. Energy balance study in pregnant Asian women. Trop Geogr Med 1981, 33: 215-18 3 Banerjee B, Saha N Energy intake and expenditure of Indian school boys. Br J Nutr 1972, 27: 483-90.
PSEUDOMEMBRANOUS COLITIS AND CEFOTAXIME
SIR,-Dr Good and Dr Benichou (Dec 14, p 1358) question the significance of frequent prescribing of cefotaxime in association with an outbreak of pseudomembranous colitis (PMC) in our sister hospital (Oct 19, p 888). In their original letter Dr Nolan and colleagues mention four cases of PMC in this hospital. Since then we have diagnosed a further seven, bringing our total to eleven in 9 months. No case of PMC had been diagnosed here over the preceding 5 years. The onset of diarrhoea in the first patient of our series occurred 6 days after his transfer from our sister hospital and during the period of the outbreak described by Nolan and colleagues. This patient was on treatment with oral flucloxacillin (but not cefotaxime) before and after his transfer. Cefotaxime had recently been used, as a second-line antibiotic, in five of the ten cases of PMC which ensued. The apparent prominence of cefotaxime in this series led us to review our hospital pharmacy records for details of antibiotic prescribing over the past 4 years. There had been no increase in prescribing of cefotaxime before or during the outbreak of PMC. This finding, together with the fact that not all of the patients affected had received cefotaxime, suggests that the outbreak in this institution resulted from the infectious nature of Clostridium
the artificial environment of
respiration
4.
chamber, the two studies show that EE obtained in the calorimeter bears a relationship with that found in free-living conditions since
5.
despite
a
69% (r2) of the variance in EE in free-living people could be accounted for by variation in EE measured in the calorimeter. This is due to the fact that in free-living situations a large part of EE is accounted for by resting and spontaneous energy expenditure, a condition typical of our sedentary society and the one encountered in the whole body calorimeter. Institute
of Physiology,
Medical
School,
Y. SCHUTZ
University of Lausanne, CH-1005 Lausanne, Switzerland
E. JÉQUIER
AM, Coward WA, Davies HL, et al. Unexpectedly low levels of energy expenditure in healthy women. Lancet 1985; i. 1419-22 2. Dauncey MJ, James WPT. Assessment of the heart rate method for determining energy expenditure in man, using a whole body calorimeter. Br J Nutr 1979; 42: 1-13. 3. Schutz Y, Dusmet M, Bessard T, et al. Estimate of 24 hour energy expenditure in man by continuous heart rate monitoring. In Proceedings of 4th Europ Nutrition Conference. The Hague. Voorlichtingsbureau voor de voeding, 1985: 199. 1. Prentice
EQUATION IN PREGNANCY and colleagues (Oct 12, p 823) raise
ENERGY
SiR.—Dr Durnin
a
very
pertinent question about energy requirement in pregnancy. In 1971 we reported on the energy cost of rest and some activities in 42 pregnant women compared with non-pregnant women and concluded that, though the energy cost increased with the advance of pregnancy, pregnant women performed their activities more economically. Our data’ are similar to those of Durnin et al. We measured the energy cost of rest and different activities in 11 women in the second and in the third trimesters. The energy cost of rest increased in the third trimester by about 9% and those of activities by 12-17%, when expressed per minute. However, there was not much increase in later pregnancy when the energy cost was expressed per kg/h: indeed there was a 4% decrease in resting metabolism. In a second study we measured daily energy intake and expenditure in 24 pregnant women over seven days to assess the
energy balance in pregnancy.2We observed an average positive balance of about 200 kcal per day (including excretion wastes which were not measured) with an average gestation period of 30 weeks and body weight of 54 - 5 kg. The surplus intake would be much less if the excretory loss of energy was considered. However, in all these women there was a great deal of inter-individual variation both of energy cost and intake. There were considerable differences in the energy cost of rest and activities between obese and thin This children4 and between active and sedentary suggests that energy cost is greatly influenced by body composition, such as proportions of body fat and muscle bulk. Inter-individual differences were much less when the energy cost was expressed per kg of calculated lean body mass.It is probably important to interpret the energy requirements or expenditure in pregnancy in the context of the much altered body composition found during pregnancy. In all our studies we found that the energy costs of rest and work in the tropics man are much less than those of Western man, even when body weight is taken into account.l,3-7 Although the evidence so far available suggests that the recommended energy requirement (FAO/WHO) for pregnant women is far in excess of the real need, far more experiments should be done before a conclusion is drawn.
6 7
Banerjee B, Saha N. Energy cost of some common physical activities of Chinese school boys. Ann Nutr Metab 1982; 26: 360-66. Banerjee B, Saha N. Energy cost of some common daily activities of active tropical male and female subjects. J Appl Physiol 1970, 29: 200-03. Saha N, Tan PY, Banerjee B. Energy balance study in Singapore medical students. Ann Nutr Metab 1985; 29: 216-22. Saha N. On the critical-fat hypothesis Curr Anthropol 1985; 26: 666.
WHICH ANTIBIOTIC FOR BACTERIA WITH INDUCIBLE CLASS I &bgr;-LACTAMASE?
SIR,-In our letter (Sept 21, p 673) commented on by Dr Shannon and colleagues (Nov 2, p 1016) we suggested the use of a combination of piperacillin or azlocillin/mezlocillin plus an aminoglycoside (rather than a third-generation cephalosporin) in the treatment of infections with gram-negative bacteria (Pseudomonus aeruginosa and Enterobacteriaceae) shown to be inducible for class I P-lactamases by the disc induction technique. The rationale behind this suggestion is that therapeutic failures due to the emergence of stably derepressed mutants (producing significant amounts of class I (3-lastamases) are less likely to occur following therapy with these penicillins than with the thirdgeneration cephalosporins (C. C. Sanders, personal communication). Indeed, therapeutic failures due to this mechanism of resistance were seldom seen before the clinical use of thirdgeneration cephalosporins.Piperacillin has low inducer activity in vitro for class I (3-lactamase production in Enterobacter and indolepositive Proteus compared with other &bgr;-lactams, including
carbenicillin.2-4
recommend the use of these penicillins in the with strains already stably derepressed. In these circumstances, we would look to newer chemotherapeutic agents unaffected by class I &bgr;-lactamases, such as the recently developed quinolones and thienamycins.
We did
not
treatment of infections
Department of Microbiology, Queen Mary’s Hospital, London SW15 5PN
M. J. WEINBREN R. M. PERINPANAYAGAM
LJU, Wise R. Newer mechanisms of resistance p lactam antibiotics in Grambacteria. J Antimicrob Chemother 1985; 16: 279-84. Yotsuji A, Inoue M, Mitsuhashi S. Induction of &bgr;-lactasase by various &bgr;-lactam anti-biotics in Enterobacter cloacae Antimicrob Ag Chemother 1980; 18:
1 Piddock
negative 2. Minami S,
382-85. Minami S, Araki Y, Inoue M, Mitsuhashi S. Inducer activity of &bgr;-lactam antibiotics for the &bgr;-lactamases of Proteus rettgeri and Proteus vulgaris. J Antibiotics 1982; 35: 1590-93 4 Minami S, Matsubara N, Yotsuji A, et al Induction of cephalosporinase production by various penicillins in enterobacteriaceae. J Antibiotics 1983; 36: 3187-95. 3
Yotsuji A,
adult.rowing
Department of Physiology, Faculty of Medicine, National University of Singapore, Singapore 0511
N. SAHA
1 Banerjee B, Khew KS, Saha N. A comparative study of energy expenditure in some common daily activities of non-pregnant and pregnant Chinese, Malay and Indian women J Obstet Gynae Br Commonw 1971; 78: 113-16. 2 Banerjee B, Saha N. Energy balance study in pregnant Asian women. Trop Geogr Med 1981, 33: 215-18 3 Banerjee B, Saha N Energy intake and expenditure of Indian school boys. Br J Nutr 1972, 27: 483-90.
PSEUDOMEMBRANOUS COLITIS AND CEFOTAXIME
SIR,-Dr Good and Dr Benichou (Dec 14, p 1358) question the significance of frequent prescribing of cefotaxime in association with an outbreak of pseudomembranous colitis (PMC) in our sister hospital (Oct 19, p 888). In their original letter Dr Nolan and colleagues mention four cases of PMC in this hospital. Since then we have diagnosed a further seven, bringing our total to eleven in 9 months. No case of PMC had been diagnosed here over the preceding 5 years. The onset of diarrhoea in the first patient of our series occurred 6 days after his transfer from our sister hospital and during the period of the outbreak described by Nolan and colleagues. This patient was on treatment with oral flucloxacillin (but not cefotaxime) before and after his transfer. Cefotaxime had recently been used, as a second-line antibiotic, in five of the ten cases of PMC which ensued. The apparent prominence of cefotaxime in this series led us to review our hospital pharmacy records for details of antibiotic prescribing over the past 4 years. There had been no increase in prescribing of cefotaxime before or during the outbreak of PMC. This finding, together with the fact that not all of the patients affected had received cefotaxime, suggests that the outbreak in this institution resulted from the infectious nature of Clostridium