940
CASES OF PNEUMON!AAMONG DRUG ABUSERS, AMSTERDAM
To establish the cause of these non-TB infiltrations, expectorated sputum samples were obtained for bacterial cultures from April, 1989, to May, 1990. 52 of these were associated with radiological abnormalities. Almost half the population was native-born Dutch men aged 20-29 (22/52); 33 were intravenous (iv) drug abusers, 17 were non-iv drug abusers, and in 2 the route of drug use was unknown. 17 were HIV-seropositive, 19 were seronegative, and in 16 the HIV status was unknown. 1 patient had TB,1 sarcoidosis,1a tumour, and 49 had radiographic findings consistent with pneumonia infiltrates. In 17 of these 49 patients, no pathogenic organisms were cultured, whereas in the other 32 Streptococcus pneumoniae and Haemophilus influenzae alone or in mixed culture were the predominant organisms (table). These 49 patients were treated with an appropriate antibiotic. In the past decade in the USA there has been an increase in pneumonia mortality rates in young adults, many of whom are iv drug abusers. Data from the Cities Mortality Surveillance System indicate that during the 1980s both the number and percentage of pneumonia and influenza attributable deaths in persons aged 25-44 as well as the pneumonia/influenza mortality rate, have more than doubled in cities with a high incidence of AIDS.1 In this study we found an X-ray abnormality prevalence rate of 28-9 per 1000 (52 in 1800). The Tuberculosis Bureau also does 2600 pre-employment chest X-rays yearly, in roughly the same age group. A review of our records showed that 15 persons per year have non-TB abnormalities (5 per 1000, which is much the same as that in the general population in the Netherlands.2 The X-ray abnormality prevalence rate in our study population was five times that of the general population, which is in accord with data from the USA. Since this study was ended (August, 1990) 4 more TB patients have been identified. The continuance of this screening programme is strongly recommended to detect and treat both TB and community-acquired pneumonia, and might prevent an increase of deaths in drug abusers, as seen in the big cities in the USA. G. E. MANOS H. VAN DEUTEKOM Municipal Health Service, P. G. H. PEERBOOMS Department of Public Health G. J. J. VAN DOORNUM and Environment, 1018 WT Amsterdam, Netherlands R. A. COUTINHO 1. Anonymous. Increase in pneumonia mortality among young adults and the HIV epidemic: New York City, United States. MMWR 1988; 38: 593. 2. Centraal Bureau voor Keuringen op Medisch—Hygienisch Gebied, annual reports 31,
32, 33, 34, 35: 1969, 1970, 1971, 1972, 1973.
Left ventricular mass and left ventricular diastolic function SIR,-Dr Shahi and colleagues’ conclusion (Aug 25, p 458) that there is no direct relation between increased left ventricular mass and ventricular diastolic dysfunction is based on the premise that pulsed-wave doppler indices of left ventricular inflow accurately reflect left ventricular diastolic function.’"’ However, this assumption has been disputed by several studies that have shown that left ventricular inflow velocity patterns are determined by many factors other than ventricular diastolic function. The early filling velocity/atrial filling velocity (E/A) ratio is dependent not
on left ventricular diastolic properties, but also on the early diastolic pressure gradient between the left atrium and ventricle. As left-atrial pressure rises, the E/A ratio may increase. Hence, although a reduced E/A ratio is frequently found in patients with diastolic dysfunction and normal left-atrial pressure, the ratio is often increased when diastolic dysfunction is associated with high left-atrial pressure.4 A ratio of 10 before therapy might therefore reflect an entirely different diastolic function than would a similar ratio in the same patient after therapy. The pretreatment ratio of I r might, for instance, be the result of diastolic dysfunction with rismg4 left-atrial pressure, producing a "pseudo-normal" EIA pattern." With antihypertensive treatment such as was given in this study, the left ventricular inflow velocity pattern could have progressed through a phase of reduced E/A ratio before returning to the usual pattern as diastolic function improved further.’ The presentation of doppler data only at 9 months rather than at monthly intervals during treatment may have resulted in data being missed. Since results were obtained 3 monthly, these data should be presented to clarify this point. Furthermore, in some patients blood pressure control was achieved through the addition of a diuretic. In view of the potential effects of diuretics on left-atrial pressure this represents a further confounding factor in the interpretation of the data presented. Finally, Shahi et al do not indicate that a Bonferroni correction was applied to the paired t-test for evaluation of the decline in left ventricular mass index. The data suggest that, had the appropriate statistical analysis been done, a decrease in left ventricular mass index would not have been significant. In addition, no attempt was made to separate left ventricular mass values for male and female subjects. Since the difference between the sexes in left ventricular mass is large, a subset analysis by gender would have been more
only
meaningful. Section of
Cardiology, University of Chicago, Chicago, Illinois 60637, USA
MAURO MOSCUCCI RICHARD MARCUS
Rokey R, Kuo LC, Zoghbi WA, Quinones MA. Determination of parameters of left ventricular diastolic filling with pulsed Doppler echocardiography. comparison with cineangiography. Circulation 1985; 71: 543-50. 2. Spirito P, Maron BJ, Bonow RO. Noninvasive assessment of left ventricular function comparative analysis of Doppler echocardiographic and radionuclide angiographic techniques J Am Coll Cardiol 1986; 7: 518-26. 3. David D, Lang RM, Neumann A, et al. Companson of Doppler indexes of left ventricular function with simultaneous high fidelity left atrial and ventricular pressures in idiopathic dilated cardiomyopathy. Am J Cardiol 1989; 64: 1173-79 4. Appleton CP, Hatle JK, Popp RL. Relation of transmitral flow velocity patterns to left ventricular diastolic function: new insights from a combined hemodynamic and Doppler echocardiographic study. J Am Coll Cardiol 1988; 12: 426-40 1.
In-vitro production of HIV-1 -specific antibody for diagnosis of perinatal infection SiR,—The early diagnosis of perinatal HIV-1 infection cannot be made on the basis of serological tests, since passively acquired maternal antibody may persist in the infant’s blood for up to 18 months after birth. In-vitro production of HIV-1-specific antibody has been proposed as a simple test to overcome this limitation. 12 BB:.ee have used this technique to follow up from birth 19 children at risk of infection; these children are now over 18 months of age. In 4 infected children who remained HIV-seropositive throughout the study, specific antibodies were found in the supernatants of unstimulated peripheral blood mononuclear cell (PBMC) cultures. However, all had negative findings from 4 toQ months of age, despite having had symptoms and HIV-1 -associated immunological abnormalities at ages 2-6 months. The remaining 15 children were symptom-free and became seronegative at various ages, but before age 18 months. In 4 children in-vitro antibody production was always negative, including that in the perinatal period-presumably in these 4 the levels of specific matemal antibodies were very low. In the other 11 children the in-nno test was positive during the first trimester of life, then became negatee Amadori’s method produced positive results (in the first 3 months of age), as did western blot in all Ichildren, and ELISA BB:JS positive in 4 of the 11.
CASES OF PNEUMON!AAMONG DRUG ABUSERS, AMSTERDAM
To establish the cause of these non-TB infiltrations, expectorated sputum samples were obtained for bacterial cultures from April, 1989, to May, 1990. 52 of these were associated with radiological abnormalities. Almost half the population was native-born Dutch men aged 20-29 (22/52); 33 were intravenous (iv) drug abusers, 17 were non-iv drug abusers, and in 2 the route of drug use was unknown. 17 were HIV-seropositive, 19 were seronegative, and in 16 the HIV status was unknown. 1 patient had TB,1 sarcoidosis,1a tumour, and 49 had radiographic findings consistent with pneumonia infiltrates. In 17 of these 49 patients, no pathogenic organisms were cultured, whereas in the other 32 Streptococcus pneumoniae and Haemophilus influenzae alone or in mixed culture were the predominant organisms (table). These 49 patients were treated with an appropriate antibiotic. In the past decade in the USA there has been an increase in pneumonia mortality rates in young adults, many of whom are iv drug abusers. Data from the Cities Mortality Surveillance System indicate that during the 1980s both the number and percentage of pneumonia and influenza attributable deaths in persons aged 25-44 as well as the pneumonia/influenza mortality rate, have more than doubled in cities with a high incidence of AIDS.1 In this study we found an X-ray abnormality prevalence rate of 28-9 per 1000 (52 in 1800). The Tuberculosis Bureau also does 2600 pre-employment chest X-rays yearly, in roughly the same age group. A review of our records showed that 15 persons per year have non-TB abnormalities (5 per 1000, which is much the same as that in the general population in the Netherlands.2 The X-ray abnormality prevalence rate in our study population was five times that of the general population, which is in accord with data from the USA. Since this study was ended (August, 1990) 4 more TB patients have been identified. The continuance of this screening programme is strongly recommended to detect and treat both TB and community-acquired pneumonia, and might prevent an increase of deaths in drug abusers, as seen in the big cities in the USA. G. E. MANOS H. VAN DEUTEKOM Municipal Health Service, P. G. H. PEERBOOMS Department of Public Health G. J. J. VAN DOORNUM and Environment, 1018 WT Amsterdam, Netherlands R. A. COUTINHO 1. Anonymous. Increase in pneumonia mortality among young adults and the HIV epidemic: New York City, United States. MMWR 1988; 38: 593. 2. Centraal Bureau voor Keuringen op Medisch—Hygienisch Gebied, annual reports 31,
32, 33, 34, 35: 1969, 1970, 1971, 1972, 1973.
Left ventricular mass and left ventricular diastolic function SIR,-Dr Shahi and colleagues’ conclusion (Aug 25, p 458) that there is no direct relation between increased left ventricular mass and ventricular diastolic dysfunction is based on the premise that pulsed-wave doppler indices of left ventricular inflow accurately reflect left ventricular diastolic function.’"’ However, this assumption has been disputed by several studies that have shown that left ventricular inflow velocity patterns are determined by many factors other than ventricular diastolic function. The early filling velocity/atrial filling velocity (E/A) ratio is dependent not
on left ventricular diastolic properties, but also on the early diastolic pressure gradient between the left atrium and ventricle. As left-atrial pressure rises, the E/A ratio may increase. Hence, although a reduced E/A ratio is frequently found in patients with diastolic dysfunction and normal left-atrial pressure, the ratio is often increased when diastolic dysfunction is associated with high left-atrial pressure.4 A ratio of 10 before therapy might therefore reflect an entirely different diastolic function than would a similar ratio in the same patient after therapy. The pretreatment ratio of I r might, for instance, be the result of diastolic dysfunction with rismg4 left-atrial pressure, producing a "pseudo-normal" EIA pattern." With antihypertensive treatment such as was given in this study, the left ventricular inflow velocity pattern could have progressed through a phase of reduced E/A ratio before returning to the usual pattern as diastolic function improved further.’ The presentation of doppler data only at 9 months rather than at monthly intervals during treatment may have resulted in data being missed. Since results were obtained 3 monthly, these data should be presented to clarify this point. Furthermore, in some patients blood pressure control was achieved through the addition of a diuretic. In view of the potential effects of diuretics on left-atrial pressure this represents a further confounding factor in the interpretation of the data presented. Finally, Shahi et al do not indicate that a Bonferroni correction was applied to the paired t-test for evaluation of the decline in left ventricular mass index. The data suggest that, had the appropriate statistical analysis been done, a decrease in left ventricular mass index would not have been significant. In addition, no attempt was made to separate left ventricular mass values for male and female subjects. Since the difference between the sexes in left ventricular mass is large, a subset analysis by gender would have been more
only
meaningful. Section of
Cardiology, University of Chicago, Chicago, Illinois 60637, USA
MAURO MOSCUCCI RICHARD MARCUS
Rokey R, Kuo LC, Zoghbi WA, Quinones MA. Determination of parameters of left ventricular diastolic filling with pulsed Doppler echocardiography. comparison with cineangiography. Circulation 1985; 71: 543-50. 2. Spirito P, Maron BJ, Bonow RO. Noninvasive assessment of left ventricular function comparative analysis of Doppler echocardiographic and radionuclide angiographic techniques J Am Coll Cardiol 1986; 7: 518-26. 3. David D, Lang RM, Neumann A, et al. Companson of Doppler indexes of left ventricular function with simultaneous high fidelity left atrial and ventricular pressures in idiopathic dilated cardiomyopathy. Am J Cardiol 1989; 64: 1173-79 4. Appleton CP, Hatle JK, Popp RL. Relation of transmitral flow velocity patterns to left ventricular diastolic function: new insights from a combined hemodynamic and Doppler echocardiographic study. J Am Coll Cardiol 1988; 12: 426-40 1.
In-vitro production of HIV-1 -specific antibody for diagnosis of perinatal infection SiR,—The early diagnosis of perinatal HIV-1 infection cannot be made on the basis of serological tests, since passively acquired maternal antibody may persist in the infant’s blood for up to 18 months after birth. In-vitro production of HIV-1-specific antibody has been proposed as a simple test to overcome this limitation. 12 BB:.ee have used this technique to follow up from birth 19 children at risk of infection; these children are now over 18 months of age. In 4 infected children who remained HIV-seropositive throughout the study, specific antibodies were found in the supernatants of unstimulated peripheral blood mononuclear cell (PBMC) cultures. However, all had negative findings from 4 toQ months of age, despite having had symptoms and HIV-1 -associated immunological abnormalities at ages 2-6 months. The remaining 15 children were symptom-free and became seronegative at various ages, but before age 18 months. In 4 children in-vitro antibody production was always negative, including that in the perinatal period-presumably in these 4 the levels of specific matemal antibodies were very low. In the other 11 children the in-nno test was positive during the first trimester of life, then became negatee Amadori’s method produced positive results (in the first 3 months of age), as did western blot in all Ichildren, and ELISA BB:JS positive in 4 of the 11.
