RESUMEN
A water solubility of 5.5 (+/-0.22) microg/L for di(2-ethylhexyl) adipate (DEHA) was measured using the slow-stir method. This value is consistent with computer estimations and over two orders of magnitude lower than that previously determined using the shake-flask method. We performed a 21-day chronic Daphnia magna limit test at an average exposure of 4.4 microg/L in laboratory diluent water to avoid insoluble test material and avoid physical entrapment. One hundred percent of the DEHA-treated organisms survived compared to 90% survival in both the controls and solvent controls. Mean neonate reproduction was 152, 137, and 148 and mean dry weight per surviving female was 0.804, 0.779, and 0.742 mg in the DEHA treatment, control, and solvent control, respectively. No adverse effects were observed.
Asunto(s)
Adipatos/toxicidad , Daphnia , Plastificantes/toxicidad , Contaminantes Químicos del Agua/toxicidad , Adipatos/química , Animales , Larva/efectos de los fármacos , Longevidad/efectos de los fármacos , Plastificantes/química , Reproducción/efectos de los fármacos , Solubilidad , Pruebas de Toxicidad , Agua/química , Contaminantes Químicos del Agua/químicaRESUMEN
During the manufacture of products containing butylbenzyl phthalate (BBP), low emissions to the air may occur. Due to potential exposure of terrestrial communities to BBP vapors, phytotoxicity tests were conducted using Chinese cabbage, white mustard, and white clover. No significant effects on shoot growth were observed at the higher BBP vapor-phase concentration tested, which measured 5.7 microg/m(3). The overall practicality of vapor-phase testing of chemicals with very low vapor pressures is reviewed. These study results suggest that environmental risk from exposure to BBP vapor is negligible for plants.
Asunto(s)
Contaminantes Ocupacionales del Aire/toxicidad , Brassica/fisiología , Medicago/fisiología , Planta de la Mostaza/fisiología , Ácidos Ftálicos/toxicidad , Contaminantes Ocupacionales del Aire/análisis , Cámaras de Exposición Atmosférica , Brassica/crecimiento & desarrollo , Medicago/crecimiento & desarrollo , Planta de la Mostaza/crecimiento & desarrollo , Ácidos Ftálicos/análisis , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/fisiología , RiesgoRESUMEN
Nonylphenol (NP) and the 9-mole ethoxylate of nonylphenol (NPE9) were synthesized with a uniform radioactive (14)C label in the aromatic ring. The [(14)C]NP isomer distribution and [(14)C]NPE9 oligomer distribution closely matched that of commercial NPE9. Biodegradation of [(14)C]NPE9 was examined under conditions simulating a river water environment, and changes in the oligomer distribution and mineralization to (14)CO(2) were monitored for 128 days. Over 40% of the [(14)C]NPE aromatic ring carbon was converted to (14)CO(2) and another 21% was incorporated into the biomass. Primary degradation of NPE (conversion to metabolites other than NP, NPE ethoxylates, and NPE carboxylates) was estimated to be 87-97%. NP was a minor metabolite, accounting for less than 0.4% of the initial NPE. These studies demonstrate that the phenolic ring of NPE is opened, metabolized, and mineralized in the aquatic environment.
Asunto(s)
Bacterias Aerobias/metabolismo , Detergentes/metabolismo , Glicoles de Etileno/metabolismo , Contaminantes Químicos del Agua/metabolismo , Bacterias Aerobias/aislamiento & purificación , Biodegradación Ambiental , Dióxido de Carbono/análisis , Dióxido de Carbono/metabolismo , Radioisótopos de Carbono , Recuento de Colonia Microbiana , Detergentes/análisis , Glicoles de Etileno/análisis , Hongos/aislamiento & purificación , Hongos/metabolismo , Fenoles/análisis , Fenoles/metabolismo , Ríos/microbiología , Microbiología del Agua , Contaminantes Químicos del Agua/análisisRESUMEN
A survey measuring concentrations of nonylphenol (NP) and its ethoxylates (NPEs) in fish was performed in the Kalamazoo River, Michigan, USA, in 1999. Of 183 fish analyzed, 59% had no detectable NP or NPE. Detected concentrations were reported to range from 3.3 (limit of detection) to 29.1 ng NP/g wet weight. To further explore the means of exposure of NP and NPE in the fish, concentrations of NP and its mono-through tri-ethoxylates (NPE(1-3)) were measured in fish, sediment, and water collected near two wastewater treatment plants on the Kalamazoo River in 2000. Samples were analyzed using exhaustive steam distillation with concurrent liquid extraction. Nonylphenol ethoxycarboxylates (NPE(1-3)C) were also analyzed in water. Concentrations of NP and NPEs in fish were less than the method detection limits (MDLs) in all the samples except one fish, which contained 3.4 ng NP/g wet weight, just above the detection limit of 3.3 ng/g. Three of 36 sediments and 1 of 24 water samples contained detectable concentrations of NP or NPE(1). NPE(2), NPE(3), and NPEC were not detected in water samples.
Asunto(s)
Peces , Sedimentos Geológicos/química , Fenoles/farmacocinética , Contaminantes Químicos del Agua/farmacocinética , Animales , Recolección de Datos , Monitoreo del Ambiente , Michigan , Fenoles/análisis , Distribución Tisular , Contaminantes Químicos del Agua/análisisRESUMEN
The ultimate biodegradation of the commercial products nonylphenol ethoxylates (NPE9), octylphenol ethoxylates (OPE9), and their biodegradation intermediates, NPE1.5, OPE1.5, NP, and OP, was measured using conventional methods. The extent of biodegradation was also determined by gas chromatography/mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC) analysis of metabolites and measurement of dissolved organic carbon. Optimized pseudo-first order degradation rate constants and half-lives were calculated from these data and from previously published data, using Larson's equation for surfactant degradation kinetics. Ultimate aerobic biodegradation of alkylphenol ethoxylates and their biodegradation intermediates has now been examined using acclimated wastewater treatment plant sludge as the microbial seed, household wastewater treatment systems, and unacclimated fresh water, seawater, and soil. Ultimate biodegradation half-lives ranged from about one to four weeks and provide definitive evidence for the extensive biodegradability of alkyphenol ethoxylates (APE) surfactants and their metabolites and their lack of persistence in the environment.
Asunto(s)
Detergentes/metabolismo , Glicoles de Etileno/metabolismo , Octoxinol/metabolismo , Tensoactivos/metabolismo , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/metabolismo , Bacterias Aerobias , Biodegradación Ambiental , Semivida , CinéticaRESUMEN
Environmental fate and aquatic effects data were examined for a series of C4 (butyl acetate, 1-butanol, isobutyl alcohol) and C8 (2-ethylhexanol and 2-ethylhexanoic acid) oxo-process chemicals. Manufacturing of these chemicals requires enclosed equipment, so environmental releases are generally limited to volatilization during their use, handling or transport. C4 compounds are more soluble and volatile, and would bind to soil and sediment to a lesser extent than C8 compounds. All five compounds were readily biodegradable based on OECD and APHA tests conducted up to 28 days. Atmospheric photo-oxidation half-lives range from 0.43 to 3.8 days. Toxicity data show that all five compounds pose generally low concern to fish, invertebrates, algae, and microorganisms. Overall, the data show that inadvertent releases of these compounds into the environment would be rapidly biodegraded in soil and water, volatilize to the atmosphere subject to photo-oxidation, while any residues remaining in water would pose a negligible threat to aquatic life.
Asunto(s)
Industria Química , Contaminantes Químicos del Agua/análisis , 1-Butanol/efectos adversos , 1-Butanol/análisis , 1-Butanol/metabolismo , Acetatos/efectos adversos , Acetatos/análisis , Acetatos/metabolismo , Animales , Biodegradación Ambiental , Butanoles/efectos adversos , Butanoles/análisis , Butanoles/metabolismo , Caproatos/efectos adversos , Caproatos/análisis , Caproatos/metabolismo , Peces , Hexanoles/efectos adversos , Hexanoles/análisis , Hexanoles/metabolismo , Invertebrados , Oxidación-Reducción , Fotoquímica , Medición de Riesgo , Microbiología del Suelo , Solubilidad , Volatilización , Microbiología del Agua , Contaminantes Químicos del Agua/efectos adversos , Contaminantes Químicos del Agua/metabolismoRESUMEN
Substantial research is currently focused on the toxicological effects of alkylphenol ethoxylates (APEs) and alkylphenols (APs) on aquatic animals. Considerable data are available on the concentrations of APEs and APs in river systems in the United States; however, few if any data are available on the tissue concentrations of fish living in these rivers. A reliable method for the analysis of nonylphenol (NP) and lower oligomer nonylphenol ethoxylates (NPE1-3) in fish tissues has been developed. Nonylphenol and NPE1-3 were extracted from fish tissues using extractive steam distillation. Normal phase high-performance liquid chromatography (HLPC) was used as a cleanup step prior to analysis by gas chromatography with mass selective detection (GC/MSD) using selected ion monitoring. Optimization of this technique resulted in consistent recoveries in excess of 70%, with the exception of NPE3 (17%). Method detection limits (MDLs) and limits of quantitation using the technique range from 3 to 20 and 5 to 29 ng/g wet weight, respectively. Nonylphenol and NPE1 were detected in subsamples (n = 6) of a single common carp captured in the Las Vegas Bay of Lake Mead (NV, USA) at average concentrations of 184+/-4 ng/g and 242+/-9 wet weight, respectively. Nonylphenol ethoxylates were not detected in the carp collected at Lake Mead.
Asunto(s)
Peces , Fenoles/farmacocinética , Contaminantes Químicos del Agua/farmacocinética , Animales , Carpas , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Carpa Dorada , Fenoles/análisis , Sensibilidad y Especificidad , Distribución Tisular , Contaminantes Químicos del Agua/análisisRESUMEN
Nonylphenol (NP) and its lower ethoxylates, nonylphenol monoethoxylate (NPE1) and nonylphenol diethoxylate (NPE2), can be present in aquatic environments at total concentrations of more than 10 microg/L. They are metabolites of nonylphenol polyethoxylates (NPE) and have been found to be weakly estrogenic. To evaluate bioaccumulation potential and identify potential risks posed by these chemicals, concentrations of NP, NPE1, NPE2, and nonylphenol triethoxylate (NPE3) were determined in the tissues of fish inhabiting various waters in Michigan. This method involves extraction of samples using exhaustive steam distillation with concurrent liquid extraction. Concentrations of NP among all sites and species ranged from <3.3 to 29.1 ng/g, ww and varied little among sites. NPE1 was detectable in some samples but at concentrations less than the method detection limit (16.8 ng/g). Concentrations of NPE2 and NPE3 in all samples were less than their respective MDLs of 18.2 and 20.6 ng/g.
Asunto(s)
Glicoles de Etileno/análisis , Peces/metabolismo , Fenoles/análisis , Contaminantes Químicos del Agua/análisis , Animales , Monitoreo del Ambiente , Agua Dulce/análisis , MichiganRESUMEN
The fate, effects, and potential environmental risks of ethylene glycol (EG) in the environment were examined. EG undergoes rapid biodegradation in aerobic and anaerobic environments (approximately 100% removal of EG within 24 h to 28 days). In air, EG reacts with photo-chemically produced hydroxyl radicals with a resulting atmospheric half-life of 2 days. Acute toxicity values (LC(50)s and EC(50)s) were generally >10,000 mg/l for fish and aquatic invertebrates. The data collectively show that EG is not persistent in air, surface water, soil, or groundwater, is practically non-toxic to aquatic organisms, and does not bioaccumulate in aquatic organisms. Potential long-term, quasi-steady state regional concentrations of EG estimated with a multi-media model for air, water, soil, and sediment were all less than predicted no effect concentrations (PNECs).
Asunto(s)
Glicol de Etileno/análisis , Glicol de Etileno/química , Radical Hidroxilo/química , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis , Anfibios , Animales , Biodegradación Ambiental , Glicol de Etileno/metabolismo , Glicol de Etileno/toxicidad , Peces , Semivida , Invertebrados , Dosificación Letal Mediana , Modelos Teóricos , Nivel sin Efectos Adversos Observados , Medición de Riesgo , Contaminantes del Suelo/toxicidad , Contaminantes Químicos del Agua/toxicidadRESUMEN
Approximately half of the approximately 40 million tonnes per annum (t/a) of acetone released worldwide arises via natural processes. The remaining releases of acetone are the focus of this assessment and arise either as a photo-degradation by-product of other organic compounds (approximately 20 million t/a) or by entering the environment from manufacturing and end uses (59,000 t/a). Multi-media modeling was used to estimate regional concentrations of acetone in air, water, soil and sediment that may occur based on these anthropogenic releases to the environment. US toxics release inventory data were used to calculate local surface water concentrations. The distributions of all regional and local concentrations in all media were below applicable predicted no effect concentrations (PNECs). Calculated regional and local concentrations of acetone, originating from all anthropogenic sources, appear unlikely to cause adverse risks to the environment.
Asunto(s)
Acetona/análisis , Contaminantes del Suelo/análisis , Contaminantes del Agua/análisis , Acetona/química , Acetona/toxicidad , Contaminantes Atmosféricos/análisis , Radical Hidroxilo , Fotoquímica , Riesgo , Contaminantes del Suelo/toxicidad , Contaminantes del Agua/toxicidadRESUMEN
Potential risks to aquatic organisms by four commercial phthalate esters, dimethyl (DMP), diethyl (DEP), di-n-butyl (DBP), and butylbenzyl (BBP), were assessed using measured and calculated concentrations in North American and Western European surface waters. Predicted no effect concentrations (PNECs) were calculated using statistical extrapolation procedures and the large aquatic toxicity database. Surface water concentrations of DMP, DEP, DBP, and BBP were calculated using reported emissions to US surface waters from the toxics release inventory (TRI). Monitoring data obtained from the US EPA STORET database and literature surveys from North America and Western Europe show that DMP, DEP, DBP, and BBP are infrequently detected in surface water. Calculated and measured concentrations of DMP, DEP, DBP, and BBP are typically several orders of magnitude below their respective PNECs, indicating that these phthalate esters do not pose a ubiquitous threat to aquatic organisms in North American and Western European surface waters.
Asunto(s)
Ácidos Ftálicos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Bases de Datos Factuales , Ésteres , Europa (Continente) , Peces , Cadena Alimentaria , Invertebrados , América del Norte , Medición de RiesgoRESUMEN
Acrylic acid, methyl acrylate, ethyl acrylate, and butyl acrylate are commercially important and widely used materials. This paper reports the results of a series of fate and aquatic toxicity studies. The mobility in soil of acrylic acid and its esters ranged from 'medium' to 'very high'. Calculated bioconcentration factors ranged from 1 to 37, suggesting a low bioconcentration potential. Acrylic acid and methyl acrylate showed limited biodegradability in the five day biochemical oxygen demand (BOD5) test, while ethyl acrylate and butyl acrylate were degraded easily (77% and 56%, respectively). Using the OECD method 301D 28-d closed bottle test, degradability for acrylic acid was 81% at 28 days, while the acrylic esters ranged from 57% to 60%. Acrylic acid degraded rapidly to carbon dioxide in soil (t1/2 < 1 day). Toxicity tests were conducted using freshwater and marine fish, invertebrates, and algae. Acrylic acid effect concentrations for fish and invertebrates ranged from 27 to 236 mg/l. Effect concentrations (LC50 or EC50) for fish and invertebrates using methyl acrylate, ethyl acrylate, and butyl acrylate ranged from 1.1 to 8.2 mg/l. The chronic MATC for acrylic acid with Daphnia magna was 27 mg/l based on length and young produced per adult reproduction day and for ethyl acrylate was 0.29 mg/l based on both the reproductive and growth endpoints. Overall these studies show that acrylic acid and the acrylic esters studied can rapidly biodegrade, have a low potential for persistence or bioaccumulation in the environment, and have low to moderate toxicity.
Asunto(s)
Acrilatos/toxicidad , Mutágenos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Acrilatos/análisis , Animales , Biodegradación Ambiental , Cyprinidae , Daphnia , Decápodos , Mutágenos/análisis , Oncorhynchus mykiss , Contaminantes Químicos del Agua/análisisRESUMEN
Bisphenol A (BPA) (CAS 80-05-7) was analyzed in receiving waters upstream and downstream of US manufacturers (1996 and 1997) and processors (1997) during seasonal low flow periods. BPA was not detected (< 1 microgram/l) in any surface water sample in 1996 or at six of seven sites in 1997. Concentrations near the seventh site ranged from 2 to 8 micrograms/l; however, its receiving stream had no measurable flow and concentrations represent undiluted effluent. All surface water concentrations from this and other studies were less than the freshwater predicted no effect concentration (PNEC) of 64 micrograms/l, suggesting that BPA discharges from manufacturing and processing facilities to surface water do not pose an environmental concern.
Asunto(s)
Fenoles/análisis , Contaminantes Químicos del Agua/análisis , Compuestos de Bencidrilo , Industrias , Control de Calidad , Estados UnidosRESUMEN
We examined the biodegradability of several metabolites of C8- and C9-alkylphenol ethoxylates, including nonylphenoxyacetic acid (NPEC1), nonylphenoxyethoxyacetic acid (NPEC2), octylphenoxyacetic acid (OPEC1), octylphenoxyethoxyacetic acid (OPEC2), and nonylphenol (NP). Using OECD method 301B (modified Sturm method), OPEC1 and OPEC2 are readily biodegradable: both compounds exceeded 60% of theoretical CO2 formation (ThCO2) by day 28, and required less than 10 days to go from 10% to 60% ThCO2. Also using method 301B, NPEC1 and NPEC2 exceeded 60% ThCO2 at day 28, but did not meet the 10 day window. Using OECD method 301F, the manometric respirometry method that measures oxygen consumption, approximately 62% of NP was biodegraded in 28 days, but required more than 10 days to go from 10% to 60% biodegradation. While the validity of the "10-day window" is currently being debated within OECD, the data show that the common metabolites of C8- and C9-APEs are rapidly degraded in the test systems used, which strongly suggests that they would not accumulate or persist in the environment.
Asunto(s)
Éteres de Etila/metabolismo , Fenoles/metabolismo , Biodegradación Ambiental , Éteres de Etila/farmacocinética , Consumo de Oxígeno , Fenoles/farmacocinética , Aguas del Alcantarillado , Factores de Tiempo , Eliminación de Residuos LíquidosRESUMEN
An experiment was conducted to determine the effects of long-term feeding of cottonseed meal on the reproductive traits of Holstein bulls. Holstein bulls approximately 6 mo of age were placed on the following treatments: 1) soybean meal + corn (CON); 2) cottonseed meal + corn (GOS); and 3) cottonseed meal + 4,000 IU vitamin E x bull(-1) x d(-1) (G+4E). The GOS and G+4E diets were formulated to supply 14 mg of free gossypol x kg(-1) BW x d(-1). These bulls had been in a previous experiment that evaluated the effects of feeding the same type of diets, but from 2 wk to 6 mo. of age. Percentage of motility, percentage of normal and live sperm, and daily sperm production were less (P<.05) in the GOS than in the other two treatments. Percentages of primary abnormalities and abnormal midpieces were greater (P<.05) in the GOS group than in the other two groups. At 12 and 16 mo. of age, bulls were given two assessments for sex drive traits. Bulls that received gossypol exhibited less sexual activity (P<.05) at the first test than bulls in other treatments. Vitamin E supplementation in bulls that received gossypol improved the number of mounts in the first test and the time to first service in the second test. There was a trend of gossypol to decrease and vitamin E to improve libido score. The results of the GOS first libido test may indicate lack of sexual maturity, which agrees with sperm production data. At the time of first test (12 mo. of age), none of GOS, two of CON, and six of G+4E bulls had reached puberty on the basis of experimental protocol. Long-term feeding of gossypol to Holstein bulls negatively affected some reproductive traits; however, vitamin E supplementation countered these adverse effects and even improved these traits.
Asunto(s)
Bovinos/fisiología , Gosipol/efectos adversos , Reproducción/efectos de los fármacos , Vitamina E/farmacología , Alimentación Animal , Animales , Aceite de Semillas de Algodón , Libido/efectos de los fármacos , Masculino , Semen/citología , Semen/efectos de los fármacos , Maduración Sexual/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Espermatozoides/ultraestructura , Testículo/anatomía & histología , Testículo/efectos de los fármacosRESUMEN
Bisphenol A (CAS 85-05-7) may be released into the environment through its use and handling, and permitted discharges. BPA is moderately soluble (120 to 300 mg/L at pH 7), may adsorb to sediment (Koc 314 to 1524), has low volatility, and is not persistent based on its rapid biodegradation in acclimated wastewater treatment plants and receiving waters (half-lives 2.5 to 4 days). BPA is "slightly to moderately" toxic (algal EC50 of 1000 micrograms/L) and has low potential for bioaccumulation in aquatic organisms (BCFs 5 to 68). The chronic NOEC for Daphnia magna is > 3146 micrograms/L. Surface water concentrations are at least one to several orders of magnitude lower than chronic effects, with most levels nondetected.
Asunto(s)
Contaminantes Ocupacionales del Aire/química , Contaminantes Ambientales/análisis , Fenoles/química , Contaminantes Ocupacionales del Aire/toxicidad , Animales , Compuestos de Bencidrilo , Biodegradación Ambiental , Contaminantes Ambientales/toxicidad , Semivida , Humanos , Fenoles/toxicidad , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidadRESUMEN
Ethylene glycol ethers and acetates are used as intermediates, solvents, and plasticizers. They primarily enter the environment from manufacturing effluents and emissions and during their use in commercial products. Therefore, an examination of their ultimate fate and toxicity, as well as their potential for exposure, was performed. Overall, these data show that ethylene glycol ethers and acetates are not persistent in the environment, are not bioaccumulative, are generally classified by U.S. Environmental Protection Agency (EPA) procedures as "practically non-toxic" to aquatic organisms based on acute toxicity, and that conservatively calculated exposures are mostly below concentrations of concern for chronic risks to aquatic life.
Asunto(s)
Acetatos/análisis , Monitoreo del Ambiente , Éteres/análisis , Glicoles de Etileno/análisis , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis , Acetatos/química , Biodegradación Ambiental , Éteres/química , Glicoles de Etileno/química , Biología Marina , Medición de Riesgo , SolubilidadAsunto(s)
Cálculos/diagnóstico por imagen , Enfermedades Pulmonares/diagnóstico por imagen , Alveolos Pulmonares/diagnóstico por imagen , Adulto , Biopsia , Colombia Británica , Líquido del Lavado Bronquioalveolar/citología , Broncoscopía , Cálculos/etnología , Cálculos/patología , Diagnóstico Diferencial , Humanos , Enfermedades Pulmonares/etnología , Enfermedades Pulmonares/patología , Malasia/etnología , Masculino , Alveolos Pulmonares/patología , Tomografía Computarizada por Rayos XRESUMEN
The present pilot study was undertaken to characterize the frequency of lung lesions in asymptomatic human deficiency virus (HIV) infected individuals with advanced HIV disease. Thirty two consecutive HIV+ homosexual males assessed for initiation of Pneumocystis carinii pneumonia (PCP) prophylaxis, were prospectively studied. All patients underwent a complete medical history, physical examination, pulmonary function tests and high resolution computed tomography (HRCT). HRCT scans were read by a single radiologist, who was blind as to the clinical status of the patient. Unexpected HRCT scan lesions were found in 60% of patients. There were no statistically significant differences between patients with normal and abnormal HRCT with respect to age, height, weight, CD4+ count, smoking history, serum albumin, alpha 1-antitrypsin level or body mass index. Forced vital capacity (FVC) (% of predicted) and peak expiratory flow rate (PEFR) (% pred) were not significantly different between groups. For patients with normal and abnormal HRCT forced expiratory volume in one second (FEV1) (% pred) was 99 +/- 12 vs 92 +/- 16, FEV1/FVC was 82 +/- 5 vs 76 +/- 9, and forced mid-expiratory flow (FEF25-75) (% pred) was 100 +/- 24 vs 77 +/- 27, respectively. There were no statistically significant differences between patients presenting with destructive versus nondestructive lung HRCT lesions. Our results demonstrate that as many as 60% of HIV-infected patients have unexpected abnormalities on HRCT at the time of starting PCP prophylaxis. We speculate that these lesions may contribute to the high frequency of spontaneous pneumothoraces previously reported in this patient population.
Asunto(s)
Infecciones por VIH/diagnóstico por imagen , Enfermedades Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Infecciones por VIH/complicaciones , Humanos , Enfermedades Pulmonares/complicaciones , Masculino , Estudios Prospectivos , Método Simple CiegoRESUMEN
OBJECTIVE: The purpose of this study was to compare the sensitivity and specificity of chest radiography with those of CT in the detection of pulmonary infections and tumors in patients with AIDS. MATERIALS AND METHODS: The study was retrospective and included the radiographs and CT scans of 139 patients. Eighty-nine had one proven thoracic complication, 17 had two proven thoracic complications, and 33 had no active intrathoracic disease at the time of the examinations. The radiographs and CT scans were interpreted blindly by two independent observers from different institutions. The observers assessed for the presence or absence of intrathoracic disease and recorded the most likely diagnosis and the degree of confidence in that diagnosis. RESULTS: The patients were more commonly correctly identified as having or not having intrathoracic disease on the basis of CT findings than on the basis of radiographic findings ( p < .01, chi-square test). Of the 106 patients with intrathoracic complications, 90% (191 of 212 interpretations) were correctly identified by the two observers on the radiograph and 96% (204 of 212 interpretations) at CT. Of 33 patients without intrathoracic disease, 73% (48 of 66 interpretations) were correctly identified at radiography and 86% (57 of 66 interpretations) at CT. Of 89 patients with one proved thoracic complication, the observers confident in their first-choice diagnosis in 34% of the cases (61 of 178 interpretations) at chest radiography and in 47% (83 of 178 interpretations) at CT. This diagnosis was correct in 67% (41 of 61) of confident radiographic interpretations as compared with 87% (72 of 83) of interpretations at CT (p < .01, chi-square test). CONCLUSION: CT is superior to chest radiography in allowing identification of patients with and without thoracic disease and in the differential diagnosis of pulmonary complications of patients with AIDS. However, the improvement in differential diagnosis is modest. Because in most cases the radiographs and CT scans were obtained as part of the clinical evaluation, the study is probably biased toward problematic clinical cases. In the majority of patients, the chest radiograph provides adequate information and CT is not warranted.