Control de un brote epidémico de histoplasmosis mediante un estudio integral / Control of a histoplasmosis epidemic outbreak by means of a comprehensive study

Se reporta el primer brote epidémico de histoplasmosis pulmonar ocurrido en el municipio de Artemisa, provincia de La Habana. El diagnóstico fue realizado teniendo en cuenta el cuadro clínico-radiológico y los resultados de los exámenes micológicos y serológicos efectuados a los pacientes. Se confirmó la fuente de infección al aislar Histoplasma capsulatum en la cueva visitada por los pacientes. Se hace una valoración de las características del foco y las medidas de control adoptadas

Estudio del valor predictivo de los parametros microbiógicos y citopatológicos de las muestras tomadas por expectoración Vs aspiracion transtraqueal en la infección respiratoria baja de origen bacteriano: informe preliminar / Studies on the predictive values of the microbiologic and cytopathologic parameters of sputum sample vs transtracheal aspiration in the low respiratory tract infections of bacterial etiology: preliminary report

Dieciséis pacientes: 10 mujeres (62,5%) y 6 hombres (37,5%) edad promedio: 51 años (rango 16 a 86) fueron ingresados al azar y prospectivamente en un estudio preliminar para determinar el Valor Predictivo Positivo (VPP) y Negativo (VPN) de muestras obtenidas por expectoración de secreción bronquial y aspiración transtraqueal (ATT) en pacientes con infección respiratoria baja clinicamente bacteriana. Los itms explorados en relación al número y tipo de floras bacterianas coloreadas con la técnica de Gram (FG), número y tipo de colonias bacterianas aerobias (CB), presencia o no de hongos junto con la presencia de colonias crecidas, y la presencia o no de atipias celulares revelaron un VPP significativo (mayor o igual 70%) solamente cuando FG fue menor de 2 y el CB fue igual a 0. El VPN fue globalmente significativo (mayor o igual al 70%) en todos los itms estudiados; indicando que la ausencia del elemento buscando en el esputo estará también ausente en la ATT. Se discute la importancia clínica práctica que de estos hechos se derivan

Evidence of hydrophobic domains in human respiratory mucins. Effect of sodium chloride on hydrophobic binding properties.

Hydrophobic binding properties of purified human respiratory mucins were studied by the fluorescence probe technique using mansylphenylalanine (Mns-Phe) as the fluorescent probe. Mucins were purified from tracheobronchial secretions of cystic fibrosis (CF) and asthmatic patients, as well as from individuals with normal lungs, according to a protocol earlier established in our laboratory. Purified mucins were subjected to reduction-alkylation and Pronase digestion to study the effects of these treatments on the hydrophobic properties of the mucins. In addition, the effects of increased NaCl concentration on the hydrophobic properties of native and reduced-alkylated mucins were also investigated. Native mucins showed evidence of a large number of low-affinity (KD approximately 10(-5) M) binding sites for the hydrophobic ligand Mns-Phe and had between 40 and 50 binding sites/mg of mucin. Reduction of mucin using dithiothreitol in the presence of 6 M guanidine hydrochloride and subsequent alkylation with iodoacetamide apparently caused marked conformational changes in the mucin molecules as revealed by the presence of both high-affinity (KD approximately 10(-6) M) and low-affinity (KD approximately 10(-5) M) binding sites for the probe and an increase in the number of probe binding sites. Pronase digestion of the native and reduced-alkylated mucins almost completely eliminated binding of the fluorescent probe to the mucins, showing that the binding sites are on the nonglycosylated, Pronase-sensitive portion of the mucin molecules. Increasing NaCl concentrations (0.03-1.0 M) did not appreciably alter the native mucin-induced Mns-Phe fluorescence, while that of the reduced-alkylated mucin-induced Mns-Phe fluorescence was progressively increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Measurement of tuberculostearic acid in sputa, pleural effusions, and bronchial washings. A clinical evaluation for diagnosis of pulmonary tuberculosis.

Gas chromatography/mass spectrometry combined with selected ion monitoring was used to measure tuberculostearic acid (TSA), in sputum, pleural effusion, and bronchial washing. The detection limit corresponded to the amount of TSA eluted from as low as 10(3) tubercle bacilli. Sputa were collected from 169 patients with active pulmonary tuberculosis, 35 clinically suspected to be active, 53 with obsolete pulmonary tuberculosis, and 160 with pulmonary diseases other than tuberculosis. TSA was positive in 90% of the patients with active pulmonary tuberculosis (152/169) and 71% of the clinically suspected cases (25/35), respectively. In contrast, less than 10% of the patients with obsolete tuberculosis or other pulmonary diseases had a positive TSA. Pleural effusions and bronchial washings were also collected from patients with active tuberculosis and from those with other diseases, as the controls. TSA in pleural effusions and bronchial washings was detected in 24 of 32 patients and 15 of 22 patients with active tuberculosis, respectively. In those with pulmonary diseases other than tuberculosis, only 8.7% of pleural effusion (4/46) and 4.3% of bronchial washing samples (3/69) showed a positive TSA. Therefore, the measurement of TSA is useful as a rapid and sensitive method for diagnosing pulmonary tuberculosis.

Concentrations of cefixime in bronchial mucosa and sputum after three oral multiple dose regimens.

In a study of 58 patients the concentrations of cefixime, a new oral cephem antibiotic, in bronchial mucosa were 35-40% of the concentrations found in simultaneously collected serum samples. The antibiotic was often undetectable in sputum despite a highly sensitive assay.

Results of a clinical and pharmacokinetic study of ceftazidime in patients with postoperative pneumonia on assisted ventilation.

Thirty-three patients who developed nosocomial pneumonia postoperatively were treated with ceftazidime, 4-6 g daily, over an average period of 7 days. Twenty-nine patients were evaluated; 13 (45%) patients were cured, five showed improvement, two relapsed, and one could not be assessed. X-rays of the chest showed no infiltrates in 17 out of the 29 cases (59%) after treatment. On the first day of treatment, ceftazidime concentrations in bronchial secretions of nine patients were estimated. The mean values of serum concentrations were: 15 min after infusion, 98 micrograms ml-1; 60 min, 63; 120 min, 44; 360 min, 20; 480 min, 13 micrograms ml-1. The mean values of the corresponding bronchial secretions were 2.9, 5.8, 10.2, 7.11 and 5.2 micrograms ml-1.

Treatment of severe chronic bronchitis with ceftazidime.

The aim of this study was to determine whether ceftazidime is more effective than other antibiotics in the treatment of severe acute exacerbation of chronic bronchitis, particularly when other antibiotics have previously failed. Our investigations showed that ceftazidime is effective and well tolerated in patients with severe chronic bronchitis and purulent sputum. The effectiveness of ceftazidime was seen in a reduction of the volume of sputum produced daily and in a colour change from yellow-green to clear-white. The absence of an effect on parameters of lung function was not unexpected since our patients had long-lasting chronic bronchitis.

Determination of biological peptide leukotrienes C4 and D4 by fluorometric detection combined with high-performance liquid chromatography.

A fluorometric procedure combined with high-performance liquid chromatography (HPLC) has been developed to separate and quantitate peptide-leukotrienes (p-LTs) C4 and D4. The method is based on pre-column dansylation of the amino terminus of the p-LTs. Its application for the determination of the amounts of p-LTs C4 and D4 in human blood and sputum is also described. The lower limit of detection of p-LTs with this method is 1 pmol.

The origin of DNA associated with mucus glycoproteins in cystic fibrosis sputum.

The relative importance of host and bacteria-derived deoxyribonucleic acid (DNA) in the increased viscoelasticity of purulent sputum in cystic fibrosis (CF) and other airway diseases is unclear. We report the identification of the DNA associated with mucus glycoproteins purified from the purulent sputum of 9 patients with CF. Mucus glycoproteins were purified from CF sputum by gel exclusion chromatography and the co-purifying DNA isolated by phenol extraction. Electrophoresis indicated that the DNA preparations had a size of approximately 300 to greater than 50,000 bases. The origin of the DNA was determined by slot blotting and subsequent hybridization with 32P-labelled DNA probes specific for human DNA sequences and those from bacterial species commonly isolated from CF sputum. The results indicated that in all cases the DNA was almost entirely human in origin. This implies that it is the patient's own DNA which may contribute to the rheological abnormalities of CF sputum.

Antibody 624H12, which detects lung cancer at early stages, recognizes a sugar sequence in the glycosphingolipid difucosylneolactonorhexaosylceramide (V3FucIII3FunLc6Cer).

Immunocytochemical staining of cells in sputum by rat monoclonal antibody 624H12 detects lung cancer 2 years prior to its detection by conventional diagnostic techniques. The antigen recognized by antibody 624H12 is a sugar sequence in the glycosphingolipid difucosylneolactonorhexaosylceramide (V3FucIII3FucnLc6Cer) whose structure is (formula see; text) Both fucosyl residues are required for high affinity binding by the antibody. The antigen was expressed in 35 of 45 specimens of cancer tissue from patients with early stage non small cell lung cancer. There was no correlation between antigen expression and patient survival.

Mineralogical analysis of sputum lith from an apparently healthy subject.

The sputum lith, 1 to 3 mm in diameter, were examined by microanalyser and by the method of X-ray diffraction, which revealed that the lith was composed of calcium carbonate and calcite in crystalline style. A composition of bronchial liths is often associated with different underlying diseases so that these nondestructive analyses seem to provide useful information for differential diagnosis. The present case is the first one to expectorate bronchial lith without marked pulmonary diseases.

A tuberculostearic acid assay in the diagnosis of sputum smear-negative pulmonary tuberculosis. A prospective study of bronchoscopic aspirate and lavage specimens.

OBJECTIVE: To determine whether the detection of tuberculostearic acid (TBSA) in bronchial aspirate and bronchoalveolar lavage specimens is useful for the rapid diagnosis of active pulmonary tuberculosis in patients suspected of having the disease. SETTING: A pulmonary clinic in a teaching hospital. PATIENTS: Forty patients suspected of active pulmonary tuberculosis but who failed to produce sputum or whose sputum smears were negative for acid-fast bacilli on at least 3 occasions, 29 of whom were subsequently confirmed to have tuberculosis. A group of 13 patients who were having fiberoptic bronchoscopy for other reasons served as controls. INTERVENTION: All patients had fiberoptic bronchoscopy; bronchial aspirate, bronchoalveolar lavage, and sputum specimens were obtained when possible. MEASUREMENTS AND MAIN RESULTS: All specimens were examined microscopically for acid-fast bacilli, cultured for mycobacteria, and assayed for TBSA by gas chromatography and mass spectrometry with selected ion monitoring. Only 4 of the 29 patients with tuberculosis were diagnosed by direct microscopy compared with 26 by TBSA assay. In 2 patients who required surgical biopsy for conventional diagnosis, the TBSA test was positive. There were no false-positive TBSA results in the 13 controls, but 2 of 5 sputum specimens from the 11 test patients in whom tuberculosis was excluded were falsely positive, probably because of contamination with mouth flora. Because sputum can rarely be obtained from these patients and may give false-positive results, it is not a good specimen for TBSA assay. Sensitivities and specificities of the test for the other specimens were as follows: aspirate, 0.52 (CI, 0.32 to 0.71) and 1.00 (CI, 0.75 to 1.00); lavage, 0.68 (CI, 0.46 to 0.85) and 1.00 (CI, 0.84 to 1.00); aspirate and lavage combined, 0.79 (CI, 0.60 to 0.92) and 1.00 (CI, 0.86 to 1.00). CONCLUSIONS: The TBSA assay for bronchial aspirate and bronchoalveolar lavage fluid is useful for rapidly diagnosing "smear-negative" pulmonary tuberculosis. In these specimens it is highly specific and more sensitive than microscopy. This assay could be used to diagnose other mycobacterial infections, however, it cannot distinguish among species.

Differences in adhesion of Pseudomonas aeruginosa to mucin glycopeptides from sputa of patients with cystic fibrosis and chronic bronchitis.

Pseudomonas aeruginosa is the most prominent colonizer of the respiratory tract of patients with cystic fibrosis, but it is not known why this occurs. P. aeruginosa adheres to mucins from normal individuals, but mucins from cystic fibrosis patients have not been studied. To compare adhesion to mucins from cystic fibrosis with other mucins, we prepared highly glycosylated mucin glycopeptides from cystic fibrosis and chronic bronchitis patients by ion-exchange and gel-filtration chromatography and measured the adhesion of P. aeruginosa 1244 to these glycopeptides. We found (i) that the most mucinlike glycopeptides from P. aeruginosa-infected cystic fibrosis sputa showed less bacterial adhesion than did the corresponding bronchitis samples, (ii) that the most adhesive activity in cystic fibrosis samples came from a fraction that contains O and N glycopeptides and may be in part a degradation product of P. aeruginosa infection, and (iii) that highly glycosylated glycopeptides of the most acidic species (sialylated and sulfated) showed no adhesion at all. A single cystic fibrosis sample not infected by P. aeruginosa showed better binding in the adhesion-positive fractions than did the infected sputa. These studies suggest that cystic fibrosis mucins may be altered after infection is established, resulting in less binding to some fragments. However, since the clinical picture shows heavy mucus colonization, other receptors, such as cellular glycolipids which have been shed into mucus, may be contributing to this colonization.

Cast bronchitis in infants and children.

Seventy-two children (age range, 3 months to 5.5 years) with a clinical diagnosis of obstructive bronchitis (asthmatoid or spastic bronchitis or bronchiolitis) were found to have bronchial casts in the gastric fluid, and in 2 additional cases casts were spontaneously expectorated in the bronchial exudate. Cast bronchitis had a long-term course of 10 to 24 months in 65 of the 74 patients. Common radiologic findings included bronchi presumably filled with secretions, areas of atelectasis, and lung emphysema of varying degrees. Cast bronchitis did not appear to be associated with eosinophilia and elevated serum IgE levels. Therefore, an extrinsic allergic mechanism is not likely involved in the pathogenesis of the condition. Bronchial casts had varying consistencies; although they were usually soft, they were sometimes rather hard. They were hollow, often ramified, and white and measured from 0.5 to 2 cm in length. Histologically, they consisted of metaplastic squamous epithelium with a varying degree of inflammatory cells and noncellular material. Some differences in biochemical composition were observed between bronchial casts and bronchial exudate of acute catarrhal bronchitis. No viruses could be isolated in 11 cast specimens. Our results suggest that cast formation is mainly related to the metaplastic transformation of the bronchial epithelium and that this metaplasia may play an important pathophysiologic role in certain infants and children with obstructive bronchitis.

pH- and protein-dependent buffer capacity and viscosity of respiratory mucus. Their interrelationships and influence on health.

The macromolecular proteins (greater than 100,000 daltons) have proved mainly responsible for the protective power of mucus against penetration of the H+ ion into the surrounding tissues. This fraction is also mainly responsible for the buffer capacity and, owing to its content of glycoproteins, for the pH-dependent viscosity of mucus. Viscosity determinations, both on native sputum and on reconstituted human alpha-acid glycoprotein, indicate that either raising or reducing the pH from neutral results in an increase in viscosity. The results suggest that individuals with low pH and/or a low protein concentration (less than 6 mg ml-1) or low buffer capacity (less than 3 mumols H+/pH unit) in their mucus, i.e. a low protective power of their mucus, will risk effects released from the underlying tissues when exposed to acidic pollutants. Alternatively, persons with higher concentrations of mucus proteins will risk effects caused by increased mucus viscosity. Sputum was tested from six smokers without any symptoms other than the ability to clear their throats easily.

Usefulness of combined light and electron microscopy: evaluation of sputum samples for asbestos to determine past occupational exposure.

Ferruginous bodies (FB) in sputa are recognized as an indicator of past exposure to asbestos. However, a great variability exists in FB production, even in individuals with a history of occupational exposure. A further complication in interpreting the presence of FBs in sputa is that all individuals in modern society are exposed to asbestos and, in lung tissue studies, have been shown to harbor appreciable numbers of asbestos fibers. Thus, some of these individuals should occasionally produce FBs in their sputa. The present study was undertaken to determine if uncoated asbestos fiber content could be used to better discriminate occupationally exposed individuals from the general population. Randomly selected sputum samples from 12 former workers in an amosite asbestos plant and 12 controls were studied. The samples were prepared for the study by digesting the sputa in sodium hypochlorite. The digests were filtered through 0.2-microns polycarbonate filters for collection of particulates. The filters were screened for FBs by light microscopy at 200 X, and the presence or absence of uncoated asbestos fibers was determined at 5000 X in an AMRAY 1000A scanning electron microscope. The use of electron microscopy revealed the presence of commercial amphiboles in the sputa of the occupationally exposed individuals and enabled a differentiation of these samples from those of the general population.

An ELISA method for the quantitation of tracheal mucins from human and nonhuman primates.

Monoclonal antibodies, 17B1 and 17Q2, which are specific for large molecular weight mucous glycoproteins of airway epithelium, have been used to develop an ELISA method to quantitate the tracheal mucins of humans and rhesus monkeys. The assay is a double-sandwich system that does not depend on either the binding of mucous antigens to the microtiter plate or the use of a second antibody. The assay protocol includes (1) coating the microtiter well with purified IgG of 17B1 or 17Q2, (2) incubating the wells with mucous samples, (3) binding of alkaline phosphatase-conjugated IgG to the wells, and (4) developing the color with phosphate substrate. This ELISA method is very sensitive for human and rhesus monkey tracheal mucins. Quantitation is not affected by the presence of various proteoglycans (keratan sulfate, hyaluronate, heparin, heparan sulfate, and chondroitin sulfate). However, the quantitation is affected by the treatment of antigen with periodic acid and endo-beta-galactosidase. Other enzymes (e.g., neuraminidase, hyaluronidase, chondroitinase, heparitinase, heparinase, fucosidase, keratanase) have no effect on the antigenicity of substrate. The quantitation is linear, with a concentration from 0.2 to 4 ng protein/sample. The ELISA method developed in this study should be useful for quantitating the mucin content of various biologic fluids, such as sputum, bronchoalveolar lavage, and media from cultures following various pharmacologic and physiologic manipulations.

Evidence for the in vivo degradation of human respiratory mucins during Pseudomonas aeruginosa infection.

The comparison of distribution of glycopeptides of sputa from patients suffering from various chronic hypersecretions has already shown an increased acidity with a decreased proportion of neutral glycopeptides in the respiratory secretions of patients suffering from cystic fibrosis, as compared to those of patients with chronic bronchitis. In order to find out whether this decrease is specific to cystic fibrosis mucins or whether it is due to a degradation of mucus by Pseudomonas aeruginosa, which infects most of the sputa from patients with this disease, mucus glycopeptides from patients with different chronic bronchial disorders, infected by Pseudomonas or not, were prepared and fractionated by ion-exchange chromatography. The neutral fraction, which has never been studied in detail, was gel-filtered, and provided two fractions, one containing true mucin glycopeptides and the other containing a mixture of peptides and glycopeptides with a lower molecular mass. In the Pseudomonas-infected samples, the true mucin glycopeptide fraction was greatly diminished as compared to this same fraction in non-Pseudomonas-infected samples; this was not specific to cystic fibrosis secretions. In contrast, the glycopeptide fraction with a lower molecular mass was greatly increased in all the Pseudomonas-infected samples. Polyacrylamide gel electrophoresis of this second fraction showed unique glycopeptide bands between 40-50 kDa in the Pseudomonas-infected samples, regardless of the origin of the samples. These bands were revealed by an antibody directed against whole cystic fibrosis mucin. Infected chronic bronchitis sputa and cystic fibrosis samples without P. aeruginosa did not show these bands. These studies therefore suggest that there are P. aeruginosa-associated changes in mucins which may result from degradation of mucins.