Isolated and synergistic effects of PM10 and average temperature on cardiovascular and respiratory mortality

OBJECTIVE To analyze the effect of air pollution and temperature on mortality due to cardiovascular and respiratory diseases. METHODS We evaluated the isolated and synergistic effects of temperature and particulate matter with aerodynamic diameter < 10 µm (PM10) on the mortality of individuals > 40 years old due to cardiovascular disease and that of individuals > 60 years old due to respiratory diseases in Sao Paulo, SP, Southeastern Brazil, between 1998 and 2008. Three methodologies were used to evaluate the isolated association: time-series analysis using Poisson regression model, bidirectional case-crossover analysis matched by period, and case-crossover analysis matched by the confounding factor, i.e., average temperature or pollutant concentration. The graphical representation of the response surface, generated by the interaction term between these factors added to the Poisson regression model, was interpreted to evaluate the synergistic effect of the risk factors. RESULTS No differences were observed between the results of the case-crossover and time-series analyses. The percentage change in the relative risk of cardiovascular and respiratory mortality was 0.85% (0.45;1.25) and 1.60% (0.74;2.46), respectively, due to an increase of 10 μg/m3 in the PM10 concentration. The pattern of correlation of the temperature with cardiovascular mortality was U-shaped and that with respiratory mortality was J-shaped, indicating an increased relative risk at high temperatures. The values for the interaction term indicated a higher relative risk for cardiovascular and respiratory mortalities at low temperatures and high temperatures, respectively, when the pollution levels reached approximately 60 μg/m3. CONCLUSIONS The positive association standardized in the Poisson regression model for pollutant concentration is not confounded by temperature, and the effect of temperature is not confounded by the pollutant levels in the time-series analysis. The simultaneous exposure to different levels of environmental factors can create synergistic effects that are as disturbing as those caused by extreme concentrations.

Treatment of relapsing chronic infections of the respiratory tract: a comparative study of the effectiveness of non specific immunotherapy with the immunoadjuvant p40 and of vaccinotherapy

The treatment of relapsing chronic infections (RCI) encounters many difficulties. In the present study, the use of the immuno adjuvant P40 either alone or in association with vaccinotherapy for the treatment of RCI turned out to be very effective, whereas vaccinotherapy alone was not. It is hypothesized that cell-mediated immunity may play a major role in controlling RCI, since the clinical improvement of the patients kept up with the positivation of previously negative skin tests carried out with either the specific infecting agent or with recall-anti gens.

Longitudinal study of acute respiratory diseases in Rio de Janeiro: occurrence of respiratory viruses during four consecutive years

The occurrence of different viruses in nasopharyngeal secretions from children less than 5 years old with acute respiratory infections (ARI) was investigated over a period of 4 years (1982-1985) in Rio de Janeiro. Of the viruses known to be associated with ARI, all but influenza C and parainfluenza types 1, 2 and 4 were found. Viruses were found more frequently in children attending emergency or pediatric wards than in outpatients. This was clearly related to the high incidence of respiratory syncytial virus (RSV) in the more severe cases of ARI. RSV positive specimens appeared mainly during the fall, over four consecutive years, showing a clear seasonal ocurrence of this virus. Emergency wards provide the best source of data for RSV surveillance, showing sharp increase in the number of positive cases coinciding with increased incidence of ARI cases. Adenovirus were the second most frequent viruses isolated and among these serotypes 1,2 and 7 were predominant. Influenza virus and parainfluenza virus type 3 were next in frequency. Influenza A virus were isolated with equal frequency in outpatient departments, emergency and pediatric wards. Influenza B was more frequent among outpatients. Parainfluenza type 3 caused outbreaks in the shanty town population annually during the late winter or spring and were isolated mainly from outpatients. Herpesvirus, enterovi-rus and rhinovirus were found less frequently. Other viruses than RSV and parainfluenza type 3 did not show a clear seasonal incidence.

Acute respiratory infections in children from a deprived urban population from Uruguay

To obtain base line data on incidence, duration, clinical characteristics and etiology of acute respiratory infections (ARI), 276 children from deprived families living in Montevideo were followed during 32 months. The target population was divided into two groups for the analysis of the results: children aged less than 12 months and those older than this age. During the follow-up period 1.056 ARI episodes were recorded. ARI incidence was 5.2 per child/year. It was 87% higher in infants than in the older group, as was the duration of the episodes. Most of the diseases were mild. Tachypnea and retractions were seldom observed, but 12 children were refered to the hospital, and 2 infants died. Viral etiology was identified in 15.3% of the episodes. RSV was the predominant agent producing annual outbreaks. Moderate to heavy colonization of the upper respiratory tract by Streptococcus pneumoniae (32.3%) and Hemophilus sp. (18.9%) was recorded during ARI episodes. This community-based study furnish original data on ARI in Uruguay. It enabled to asses the impact of these infections on childhood.

Bacterial agents isolated from cerebrospinal fluid of patients with Acquired Immunodeficiency Syndrome (AIDS) and neurological complications

Cerebrospinal fluid (CSF) samples from 2083 patients with acquired immunodeficiency syndrome (AIDS) and neurological complications were bacteriologically examined during a period of 7 years (1984-1990). The percentage of patients who had at least one bacterial agent cultured from the CSF was 6.2%. Mycobacterium tuberculosis was the most frequently isolated agent (4.3%), followed by Mycobacterium avium complex or MAC (0.7%), Pseudomonas spp (0.5%), Enterobacter spp (0.4%), and Staphylococcus aureus (0.3%). Among 130 culture positive patients, 89 (68.5%) had M. tuberculosis and 15 (11.6%) had MAC. The frequency of bacterial isolations increased from 1988 (5.2%) to 1990 (7.2%), partly due to the increase in MAC isolations. Bacterial agents were more frequently isolated from patients in the age group 21-30 years and from women (p<0.05).

Clinical and endoscopic findings in the mucosae of the upper respiratory and digestive tracts in post-treatment follow-up of paracoccidioidomycosis patients

Systematic examination of the upper respiratory and digestive tracts (URDT) was performed in a group of 80 paracoccidioidomycosis (PCM) patients submitted to post-treatment follow-up ranging from 8 months to 17 years. Mucosae of the URDT had been involved prior to specific treatment in 74 patients, distributed as follows: oropharynx, 50 (41 alone, 7 in association with the larynx, and 2 with the nasal mucosa); larynx, 30 (23 alone and 7 in association); and nasal mucosa, 3(1 alone and 2 in association). Inactive lesions were observed in all the 50 patients with lesions of the oropharynx, 3 of whom with deforming scars (1 with retraction of the tongue and 2 with narrowing of the oral orifice). One case presented a destructive lesion, with perfuration of the palate. Of the other 46 cases, examination showed nacreous white striated scars which were nearly imperceptible in some cases and in others displayed partial retraction of anatomical structures without any alteration of their features. Patients presented a high rate of missing teeth. In 3 patients with involvement of the nasal mucosa, none of whom presented active PCM lesions, 2 still had nasal voices. In 30 patients with lesions of the larynx, 1 suffered a relapse of PCM and 2 developed epidermoid carcinoma. Of the other 27 cases, none of whom had active PCM lesions, 15 presented dysphonia, 3 were tracheotomized, and 9 were asymptomatic.

Genomic characterization of adenovirus serotype 7 isolated in Brazil from acute respiratory disease patients during the period from 1980 to 1991

Forty isolates of adenovirus type 7 were analized by restriction enzyme digestion with BamHI, SmaI, EcoRI and HindIII. These isolates were obtained from acute respiratory disease patients during the years 1980 to 1991. Only two genomic types were found: Ad7b and Ad7e, with Ad7b (87.5%) being more frequent than Ad7e (12.5%). The genomic type Ad7e appeared in the years 1980, 1981 and 1983. Ad7b appeared in 1982 and it was the only genomic type found from 1984 to 1991. Both genomic types were responsible for lower (LRTI) and upper (URTI) respiratory tract infection, but the proportion LRTI/URTI is higher for Ad7b (25/6) than for Ad7e (1/4).

ENTEROVIRUSES ISOLATED FROM PATIENTS WITH ACUTE RESPIRATORY INFECTIONS DURING SEVEN YEARS IN RIO DE JANEIRO (1985-1991)

Enteroviruses were investigated in respiratory secretions collected from patients with acute respiratory infections (ARI) over a seven year period (1985-1991), as part of a longitudinal study of ARI aetiology. All the viruses that are most commonly associated with ARI were found in this study. Among the virus isolates, enteroviruses were only less frequent than respiratory syncytial viruses, adenoviruses and influenzaviruses. Forty five enterovirus samples were isolated from patients with either upper respiratory tract infections (URTI) or lower respiratory tract infections (LRTI). From these enterovirus isolates, thirty one samples were identified as poliovirus (n=18) and non polio enterovirus (n=13) by serum neutralization. Poliovirus were identified as type 1 and 2 and all of them were vaccinal strains. From thirteen non polio enterovirus, twelve were identified as echovirus serotypes 1, 2, 7, 11, 19 and 31. The remainder was identified as coxsackievirus B4.

Clinical patterns and seasonal trends in respiratory syncytial virus hospitalizations in São Paulo, Brazil

The respiratory viruses are recognized as the most frequent lower respiratory tract pathogens for infants and young children in developed countries but less is known for developing populations. The authors conducted a prospective study to evaluate the occurrence, clinical patterns, and seasonal trends of viral infections among hospitalized children with lower respiratory tract disease (Group A). The presence of respiratory viruses in children's nasopharyngeal was assessed at admission in a pediatric ward. Cell cultures and immunofluorescence assays were used for viral identification. Complementary tests included blood and pleural cultures conducted for bacterial investigation. Clinical data and radiological exams were recorded at admission and throughout the hospitalization period. To better evaluate the results, a non- respiratory group of patients (Group B) was also constituted for comparison. Starting in February 1995, during a period of 18 months, 414 children were included- 239 in Group A and 175 in Group B. In Group A, 111 children (46.4%) had 114 viruses detected while only 5 children (2.9%) presented viruses in Group B. Respiratory Syncytial Virus was detected in 100 children from Group A (41.8%), Adenovirus in 11 (4.6%), Influenza A virus in 2 (0.8%), and Parainfluenza virus in one child (0.4%). In Group A, aerobic bacteria were found in 14 cases (5.8%). Respiratory Syncytial Virus was associated to other viruses and/or bacteria in six cases. There were two seasonal trends for Respiratory Syncytial Virus cases, which peaked in May and June. All children affected by the virus were younger than 3 years of age, mostly less than one year old. Episodic diffuse bronchial commitment and/or focal alveolar condensation were the clinical patterns more often associated to Respiratory Syncytial Virus cases. All children from Group A survived. In conclusion, it was observed that Respiratory Syncytial Virus was the most frequent pathogen found in hospitalized children admitted for severe respiratory diseases. Affected children were predominantly infants and boys presenting bronchiolitis and focal pneumonias. Similarly to what occurs in other subtropical regions, the virus outbreaks peak in the fall and their occurrence extends to the winter, which parallels an increase in hospital admissions due to respiratory diseases.

Use of selective medium for Burkholderia cepacia isolation in respiratory samples from cystic fibrosis patients

Burkholderia cepacia colonizes cystic fibrosis (CF) patients. We evaluated the impact of the use of a selective medium in the rate of B. cepacia recovery from respiratory samples of CF patients. During a 6-month period, respiratory samples were collected from 106 CF patients and cultivated on selective media including a B. cepacia selective medium. Confirmation of the identity of B. cepacia isolates was carried out by species specific PCR and determination of genomovar status performed by a sequential PCR approach. Results of B. cepacia isolation during this period were compared to the preceding two years, when the sample processing was identical except for the lack of the B. cepacia selective medium. B. cepacia was isolated in 11/257 (4.2%) of the samples using the selective medium, in contrast with the preceding two years, when it was isolated in 6/1029 samples (0.58%), p < 0.0001. Identity of all 11 isolates was confirmed by PCR and genomovar determination was accomplished in all but one isolate. These results suggest that the use of a selective medium increases recovery rate of B. cepacia from respiratory samples.

Fonsecaea pedrosoi cerebral phaeohyphomycosis ("chromoblastomycosis"): first human culture-proven case reported in Brazil

Cerebral phaeohyphomycosis ("chromoblastomycosis") is a rare intracranial lesion. We report the first human culture-proven case of brain abscesses due to Fonsecaea pedrosoi in Brazil. The patient, a 28 year-old immunocompetent white male, had ocular manifestations and a hypertensive intracranial syndrome. Magnetic resonance imaging (MRI) of the brain revealed a main tumoral mass involving the right temporo-occipital area and another smaller apparently healed lesion at the left occipital lobe. A cerebral biopsy was performed and the pathological report was cerebral chromoblastomycosis. The main lesion was enucleated surgically and culture of the necrotic and suppurative mass grew a fungus identified as Fonsecaea pedrosoi. The patient had received a knife wound sixteen years prior to his hospitalization and, more recently, manifested a pulmonary granulomatous lesion in the right lung with a single non-pigmented form of a fungus present. It was speculated that the fungus might have gained entrance to the host through the skin lesion, although a primary respiratory lesion was not excluded. The patient was discharged from the hospital still with ocular manifestations and on antimycotic therapy and was followed for eight months without disease recurrence. Few months after he had complications of the previous neuro-surgery and died. A complete autopsy was performed and no residual fungal disease was found.

Respiratory tract intracavitary colonization due to Scedosporium apiospermum: report of four cases

Four cases of respiratory tract intracavitary colonization (fungus ball) due to Scedosporium apiospermum (teleomorph, Pseudallescheria boydii) are reported. The need for a careful search for anneloconidia, in order to establish the etiologic diagnosis in the clinical specimen by microscopy, is emphasized.

Incidence of respiratory viruses in preterm infants submitted to mechanical ventilation

The objectives of this study were to determine the incidence of infection by respiratory viruses in preterm infants submitted to mechanical ventilation, and to evaluate the clinical, laboratory and radiological patterns of viral infections among hospitalized infants in the neonatal intensive care unit (NICU) with any kind of acute respiratory failure. Seventy-eight preterm infants were studied from November 2000 to September 2002. The newborns were classified into two groups: with viral infection (Group I) and without viral infection (Group II). Respiratory viruses were diagnosed in 23 preterm infants (29.5%); the most frequent was respiratory syncytial virus (RSV) (14.1%), followed by influenza A virus (10.2%). Rhinorrhea, wheezing, vomiting and diarrhea, pneumonia, atelectasis, and interstitial infiltrate were significantly more frequent in newborns with nosocomial viral infection. There was a correlation between nosocomial viral infection and low values of C-reactive protein. Two patients with mixed infection from Group I died during the hospital stay. In conclusion, RSV was the most frequent virus in these patients. It was observed that, although the majority of viral lower respiratory tract infections had a favorable course, some patients presented a serious and prolonged clinical manifestation, especially when there was concomitant bacterial or fungal infection.

Effect of Cysticercus cellulosae fractions on the respiratory burst of pig neutrophils

Neutrophils, eosinophils and macrophages are cells that interact with invading parasites and naive hosts have been shown to have anti-parasitic activity. The initial reaction of these leukocytes is the generation of reactive oxygen species (ROS) to play in parasite expulsion. The present work was carried out to study the effect of total extract, scolex and membrane fractions from Cysticercus cellulosae on respiratory burst by pig neutrophils. Hydrogen peroxide (H2O2) production by neutrophils incubated with metacestode fractions from C. cellulosae showed an increase of: 190% (total extract), 120% (scolex) and 44% (membrane). High antioxidant catalatic activity (33%, 28%, 28% by total extract, scolex and membrane, respectively) was observed in neutrophils incubated with metacestode fractions, which could be an attempt at self-protection. Scolex and membrane fractions increased the phagocytic capacity of neutrophils (44% and 28%, respectively). On the other hand, total cysticerci did not alter the phagocytosis, possibly due to modifications in membrane function, caused by high ROS production from neutrophils in the presence of total cysticerci. Total fraction from C. cellulosae is toxic for neutrophils as shown by the decrease in phagocytic capacity, probably caused by high levels of ROS formation. The difference in toxicity of total extract, scolex and membrane fractions on neutrophils can be explained by the presence of an antigenic effect of the vesicular fluid in the total extract of C. cellulosae.