- Email: [email protected]
INFECTIVE ENDOCARDITIS
1018 amount of urinary protein, or degree of haematuria. After one year, renal function (evaluated by the reciprocal of the serum creatinine) had not changed significantly in the EPA group (1/1-88 to 112 -1dl/mg); the controls significantly deteriorated (1/1 -7to 1/3 -7dl/mg, p<0 - 01), and two of them had to go onto chronic haemodialysis during the year. EPA has favourable effects on blood vessels,4even in chronic haemodialysis patients.5 Our results indicate that EPA might be a safe and useful agent to stop the progression of IgA nephropathy.
CHOLESTEROL LOWERING AND RISK OF CORONARY HEART DISEASE
hypertension, daily
Department of Internal Medicine, Sakura National Hospital, Sakura City, Chiba 285, Japan
TOMOHITO HAMAZAKI* SUMIO TATENO HIDEO SHISHIDO
*Present address: 1st Department of Internal Medicine, Toyama Medical and Pharmaceutical University, Toyama City, Toyama 930-01, Japan.
TROPICAL SPRUE
SIR,-One reason why clinicians may find the epidemiologists’ "idea of population-based control frightening" (Professor Tunstall Pedoe, April 14) in relation to plasma cholesterol and the risk of coronary heart disease is the thought that control (of the nation’s diet) should be instituted by anyone, particularly epidemiologists who assume the role of health educators. Control implies legislation, and surely this is justified only when there is the certainty of definite benefit. At present, the evidence falls far short of proof that reduction of cholesterol levels in the whole population will lead to less coronary heart disease-and control, therefore, should not enter the debate. Judgment, soundadvice to Government, and better use of existing services and agencies as to how best to achieve reduction in the incidence of coronary heart disease is what is needed, especially for those most at risk, and this is well exemplified by the recent
SIR,-When the precise aetiology of a disease is unknown, definitions are important. Dr Cook (March 31, p 721) claims that tropical sprue is a form of post-infective malabsorption. He suggests that it starts with an acute intestinal infection of bacterial, viral, or parasitic origin. He is clearly describing something which few who have worked with tropical sprue would recognise. Tropical sprue is usually defined as a condition of malabsorption occurring in defined geographical areas in the tropics in which no bacterial, viral, or parasitic infection can be detected. It may present with acute diarrhoea but it may also be latent for long periods with no initially recognisable symptoms, the condition only becoming apparent as nutritional deficiencies of folic acid and vitamin Bi2 develop. This may happen many years after an individual has left the relevant tropical area. The term "post-infective tropical malabsorption", which Cook has not defined, implies an aetiology which is belied by the facts and is therefore inappropriate. Cook makes great play with the comparison between intestinal bacterial overgrowth in tropical sprue and in the stagnant loop syndrome. The presence of bacterial overgrowth in the small intestine has been repeatedly demonstrated in tropical sprue but the abnormal flora is predominantly aerobic, in contrast to the anaerobic flora so characteristic of the stagnant loop syndrome. The functional significance of bacterial- overgrowth is also different in the two conditions. Whereas bile salt deconjugation and dehydroxylation caused by anaerobic bacteria are characteristic findings in the stagnant loop syndrome, this is not the case in tropical sprue. If stagnation occurs as a result of delayed intestinal transit in tropical sprue, it therefore produces a quite different pattern of bacterial overgrowth from that in the stagnant loop syndrome. Furthermore, bacterial overgrowth in the stagnant loop syndrome is rarely associated with mucosal lesions in man, in contrast to the mucosal lesions which may be extensive in tropical sprue. Cook refers to the work of William Hillary on tropical malabsorption in Barbados in the 1750s. He might also have heeded Hillary’s advice in the introduction to A Rational and Mechanical Essay on the Smallpox (1735): "... if we once quit our Reason for Mystery ... we must wander through endless Mazes, and dark Labyrinths, playing at Hazard with Men’s lives, and suffer ourselves to ramble wherever conceited Imagination or Whymsical Hypothesis will lead us". The term "post-infective tropical malabsorption" is a dark labyrinth. In the present state of knowledge, it would be advisable to retain the term tropical sprue to describe the syndrome of intestinal malabsorption which occurs among residents in or visitors to certain regions of the tropics, as suggested by the Wellcome Trust collaborative study in 1971.1 Clinical Research Centre, Harrow, Middlesex HA 1 3UJ
CHRISTOPHER BOOTH
JZ, Schmidt EB, Nielsen AH, Dyerberg J. The effect of n-6 and n-3 polyunsaturated fatty acids on hemostasis, blood lipids and blood pressure. Thromb
4. Mortensen
Haemostas 1983; 50: 543-46. T, Nakazawa R, Tateno S, et al. Effects of fish oil rich in eicosapentaenoic acid (EPA) on serum lipid in hyperlipidemic hemodialysis patients. Kidney Int (in
5. Hamazaki
press).
Cardiovascular Research Unit,
University of Edinburgh, Hugh Robson Building, George Square, Edinburgh EH8 9XF
Collaborative Study 1961-69. Tropical Edinburgh: Churchill Livingstone, 1971.
sprue and
megaloblastic
M. F. OLIVER
INFECTIVE ENDOCARDITIS
SIR,-Your March 17 editorial suggests that oral therapy of endocarditis may be substituted for intravenous therapy after 10-14 days, provided that the patient is clinically improved and afebrile. However, Dr Oakley and Dr Darrell (March 24, p 690) comment that the change to "inferior" oral regimens is a potent cause of treatment failure. Neither editorial nor letter states the role of the laboratory in predicting the effect of changing to oral therapy or in confirming that satisfactory therapy continues. We routinely measure the bactericidal concentration of the antibiotics against the offending pathogen, and the patient’s serum is "back-titrated" to confirm that killing of the organism occurs. Backtitration also gives an estimate of the margin of "overkill". Armed with this information clinicians can reasonably predict whether therapeutic levels will ever be achieved by the oral route. During oral therapy back-titration of the patient’s serum to determine both pre-dose and post-dose activity is an essential part of management in our hospital, and when a combination of drugs (eg, flucloxacillin and fusidic acid) is being used we change one drug at a time to the oral route. We concur with the view of Oakley and Darrell that a change to oral penicillin is inadvisable because its absorption is unpredictable, and we recommend oral amoxycillin. We aim to use intravenous therapy for at least 3 weeks and oral therapy for a further 3 weeks. Whilst we do not always manage to change to oral therapy, it is our objective whenever possible. Our policy is beneficial to the patient’s morale-and it reduces the pharmacy bill while still enabling us to sleep soundly. Microbiology
R. H. GEORGE E. D. SILOVE J. V. DE GIOVANNI
and Cardiac Departments, Children’s Hospital, Birmingham B16 8ET
IS IMPROVED DIABETIC CONTROL REALLY DANGEROUS?
SIR,-The 1983 paper from the Steno group2and the reports of the Kroc group, showing that mild background retinopathy tends to get worse over a short period of improved control (8-12 months), have led some people to a curious view of continuous subcutaneous insulin infusion (CSII). For example, Dr Knight and his colleagues (March 24, p 681) claim that a patient with poor control, in whom there was some improvement of diabetic control (HbAl fell from 14’ 8% to 10%) after 4 months on CSII, had transient ischaemia in one eye and ischaemic optic neuropathy in the other as a result of the improved control. The findings of the Kroc and Steno study group 1. Rose G, et al. 1984. 2. Lauritzen
1. Wellcome Trust
anaemia.
1
Canterbury report.
Coronary heart
disease
prevention. plans for action.
London: Pitman,
P, Frost-Larsen K, Larsen HW, Deckert T. Effect of 1 year of near-normal on retinopathy in insulin-dependent diabetics. Lancet 1983, i:
blood glucose levels 200-04.
CHOLESTEROL LOWERING AND RISK OF CORONARY HEART DISEASE
hypertension, daily
Department of Internal Medicine, Sakura National Hospital, Sakura City, Chiba 285, Japan
TOMOHITO HAMAZAKI* SUMIO TATENO HIDEO SHISHIDO
*Present address: 1st Department of Internal Medicine, Toyama Medical and Pharmaceutical University, Toyama City, Toyama 930-01, Japan.
TROPICAL SPRUE
SIR,-One reason why clinicians may find the epidemiologists’ "idea of population-based control frightening" (Professor Tunstall Pedoe, April 14) in relation to plasma cholesterol and the risk of coronary heart disease is the thought that control (of the nation’s diet) should be instituted by anyone, particularly epidemiologists who assume the role of health educators. Control implies legislation, and surely this is justified only when there is the certainty of definite benefit. At present, the evidence falls far short of proof that reduction of cholesterol levels in the whole population will lead to less coronary heart disease-and control, therefore, should not enter the debate. Judgment, soundadvice to Government, and better use of existing services and agencies as to how best to achieve reduction in the incidence of coronary heart disease is what is needed, especially for those most at risk, and this is well exemplified by the recent
SIR,-When the precise aetiology of a disease is unknown, definitions are important. Dr Cook (March 31, p 721) claims that tropical sprue is a form of post-infective malabsorption. He suggests that it starts with an acute intestinal infection of bacterial, viral, or parasitic origin. He is clearly describing something which few who have worked with tropical sprue would recognise. Tropical sprue is usually defined as a condition of malabsorption occurring in defined geographical areas in the tropics in which no bacterial, viral, or parasitic infection can be detected. It may present with acute diarrhoea but it may also be latent for long periods with no initially recognisable symptoms, the condition only becoming apparent as nutritional deficiencies of folic acid and vitamin Bi2 develop. This may happen many years after an individual has left the relevant tropical area. The term "post-infective tropical malabsorption", which Cook has not defined, implies an aetiology which is belied by the facts and is therefore inappropriate. Cook makes great play with the comparison between intestinal bacterial overgrowth in tropical sprue and in the stagnant loop syndrome. The presence of bacterial overgrowth in the small intestine has been repeatedly demonstrated in tropical sprue but the abnormal flora is predominantly aerobic, in contrast to the anaerobic flora so characteristic of the stagnant loop syndrome. The functional significance of bacterial- overgrowth is also different in the two conditions. Whereas bile salt deconjugation and dehydroxylation caused by anaerobic bacteria are characteristic findings in the stagnant loop syndrome, this is not the case in tropical sprue. If stagnation occurs as a result of delayed intestinal transit in tropical sprue, it therefore produces a quite different pattern of bacterial overgrowth from that in the stagnant loop syndrome. Furthermore, bacterial overgrowth in the stagnant loop syndrome is rarely associated with mucosal lesions in man, in contrast to the mucosal lesions which may be extensive in tropical sprue. Cook refers to the work of William Hillary on tropical malabsorption in Barbados in the 1750s. He might also have heeded Hillary’s advice in the introduction to A Rational and Mechanical Essay on the Smallpox (1735): "... if we once quit our Reason for Mystery ... we must wander through endless Mazes, and dark Labyrinths, playing at Hazard with Men’s lives, and suffer ourselves to ramble wherever conceited Imagination or Whymsical Hypothesis will lead us". The term "post-infective tropical malabsorption" is a dark labyrinth. In the present state of knowledge, it would be advisable to retain the term tropical sprue to describe the syndrome of intestinal malabsorption which occurs among residents in or visitors to certain regions of the tropics, as suggested by the Wellcome Trust collaborative study in 1971.1 Clinical Research Centre, Harrow, Middlesex HA 1 3UJ
CHRISTOPHER BOOTH
JZ, Schmidt EB, Nielsen AH, Dyerberg J. The effect of n-6 and n-3 polyunsaturated fatty acids on hemostasis, blood lipids and blood pressure. Thromb
4. Mortensen
Haemostas 1983; 50: 543-46. T, Nakazawa R, Tateno S, et al. Effects of fish oil rich in eicosapentaenoic acid (EPA) on serum lipid in hyperlipidemic hemodialysis patients. Kidney Int (in
5. Hamazaki
press).
Cardiovascular Research Unit,
University of Edinburgh, Hugh Robson Building, George Square, Edinburgh EH8 9XF
Collaborative Study 1961-69. Tropical Edinburgh: Churchill Livingstone, 1971.
sprue and
megaloblastic
M. F. OLIVER
INFECTIVE ENDOCARDITIS
SIR,-Your March 17 editorial suggests that oral therapy of endocarditis may be substituted for intravenous therapy after 10-14 days, provided that the patient is clinically improved and afebrile. However, Dr Oakley and Dr Darrell (March 24, p 690) comment that the change to "inferior" oral regimens is a potent cause of treatment failure. Neither editorial nor letter states the role of the laboratory in predicting the effect of changing to oral therapy or in confirming that satisfactory therapy continues. We routinely measure the bactericidal concentration of the antibiotics against the offending pathogen, and the patient’s serum is "back-titrated" to confirm that killing of the organism occurs. Backtitration also gives an estimate of the margin of "overkill". Armed with this information clinicians can reasonably predict whether therapeutic levels will ever be achieved by the oral route. During oral therapy back-titration of the patient’s serum to determine both pre-dose and post-dose activity is an essential part of management in our hospital, and when a combination of drugs (eg, flucloxacillin and fusidic acid) is being used we change one drug at a time to the oral route. We concur with the view of Oakley and Darrell that a change to oral penicillin is inadvisable because its absorption is unpredictable, and we recommend oral amoxycillin. We aim to use intravenous therapy for at least 3 weeks and oral therapy for a further 3 weeks. Whilst we do not always manage to change to oral therapy, it is our objective whenever possible. Our policy is beneficial to the patient’s morale-and it reduces the pharmacy bill while still enabling us to sleep soundly. Microbiology
R. H. GEORGE E. D. SILOVE J. V. DE GIOVANNI
and Cardiac Departments, Children’s Hospital, Birmingham B16 8ET
IS IMPROVED DIABETIC CONTROL REALLY DANGEROUS?
SIR,-The 1983 paper from the Steno group2and the reports of the Kroc group, showing that mild background retinopathy tends to get worse over a short period of improved control (8-12 months), have led some people to a curious view of continuous subcutaneous insulin infusion (CSII). For example, Dr Knight and his colleagues (March 24, p 681) claim that a patient with poor control, in whom there was some improvement of diabetic control (HbAl fell from 14’ 8% to 10%) after 4 months on CSII, had transient ischaemia in one eye and ischaemic optic neuropathy in the other as a result of the improved control. The findings of the Kroc and Steno study group 1. Rose G, et al. 1984. 2. Lauritzen
1. Wellcome Trust
anaemia.
1
Canterbury report.
Coronary heart
disease
prevention. plans for action.
London: Pitman,
P, Frost-Larsen K, Larsen HW, Deckert T. Effect of 1 year of near-normal on retinopathy in insulin-dependent diabetics. Lancet 1983, i:
blood glucose levels 200-04.