Proteinose alveolar: manifestação paraneoplásica?

Pulmonary alveolar proteinosis (PAP) is a rare condition of unknown etiology. It hasbeen described as the presence of periodic acid-Schiff-positive proteinaceous material(rich in lipids) in the alveoli. Its pathogenesis is believed to consist of an overproductionor surfactant removal defect at the lung. The association of PAP with respiratorydiseases, silicosis, exposure to aluminium or titanium, and hematological neoplasiashas been reported. Here we report two cases of pulmonary alveolar proteinosis andneoplasm diagnosed at the PulmonaryDepartment at Hospital de Clínicas de PortoAlegre.A proteinose alveolar (PA) é uma doença rara, de etiologia desconhecida, caracterizadapelo acúmulo alveolar de material proteináceo PAS + (ácido-periódico de Schiff), ricoem fosfolipídios. Acredita-se que a patogênese consiste na superprodução ou defeitona remoção do surfactante ao nível do epitélio pulmonar (10). A PA pode estar associadaa infecções respiratórias (1,2), silicose (3), exposição ao alumínio (4), titânio (5) e aneoplasias hematológicas (6-8). Neste presente artigo, serão apresentados dois relatosde casos de proteinose alveolar e carcinomas diagnosticados no Serviço de Pneumologiado Hospital de Clínicas de Porto Alegre

Continuous positive airway pressure and body position alter lung clearance of the radiopharmaceutical 99mtechnetium-diethylenetriaminepentaacetic acid (99mTc-DTPA)

The purpose of this investigation was to evaluate the pulmonary clearance rate of 99mtechnetium-diethylenetriaminepentaacetic acid (99mTc-DTPA) through the use of continuous positive airway pressure (CPAP) in different postures. It was a quasi-experimental study involving 36 healthy individuals with normal spirometry. 99mTc-DTPA, as aerosol, was nebulized for 3 min with the individual in a sitting position. The pulmonary clearance rate was assessed through pulmonary scintigraphy under spontaneous breathing and under 20 and 10 cmH2O CPAP in the sitting and supine positions. The clearance rate was expressed as the half-time (T1/2), that is, the time for the activity to decrease to 50% of the peak value. 20 cmH2O CPAP produced significant reduction of the T1/2 of 99mTc-DTPA in the supine position (P = 0.009) and in the sitting position (P = 0.005). However, 10 cmH2O CPAP did not alter the T1/2 of DTPA in both positions. The postural variation from supine to the sitting position with 10 cmH2O CPAP (P = 0.01) and 20 cmH2O (P = 0.02) also reduced the T1/2 of 99mTc-DTPA. High levels of positive pressure in normal lungs resulted in faster 99mTc-DTPA clearance. Moreover, the sitting position further increased the clearance rate of the 99mTc radioaerosol imaging in the two pressure levels studied.Key words: Continuous positive airway pressure, 99mTc-DTPA, scintigraphy, posture

Dissociation between skin test reactivity and anti-aeroallergen IgE: Determinants among urban Brazilian children.

BACKGROUND: The dissociation between specific IgE and skin prick test reactivity to aeroallergens, a common finding in populations living in low and middle-income countries, has important implications for the diagnosis and treatment of allergic diseases. Few studies have investigated the determinants of this dissociation. In the present study, we explored potential factors explaining this dissociation in children living in an urban area of Northeast Brazil, focusing in particular on factors associated with poor hygiene. METHODS: Of 1445 children from low income communities, investigated for risk factors of allergies, we studied 481 with specific IgE antibodies to any of Blomia tropicalis, Dermatophagoides pteronyssinus, Periplaneta americana and Blatella germanica allergens. Data on demographic, environmental and social exposures were collected by questionnaire; serum IgG and stool examinations were done to detect current or past infections with viral, bacterial, protozoan and intestinal helminth pathogens. We measured atopy by skin prick testing (SPT) and specific IgE (sIgE) to aerollergens in serum (by ImmunoCAP). SIgE reactivity to B. tropicalis extract depleted of carbohydrates was measured by an in-house ELISA. Total IgE was measured by in house capture ELISA. SNPs were typed using Illumina Omni 2.5. RESULTS: Negative skin prick tests in the presence of specific IgE antibodies were frequent. Factors independently associated with a reduced frequency of positive skin prick tests were large number of siblings, the presence of IgG to herpes simplex virus, Ascaris lumbricoides and Trichuris trichiura infections, living in neighborhoods with infrequent garbage collection, presence of rodents and cats in the household and sIgE reactivity to glycosylated B. tropicalis allergens. Also, SNP on IGHE (rs61737468) was negatively associated with SPT reactivity. CONCLUSIONS: A variety of factors were found to be associated with decreased frequency of SPT such as unhygienic living conditions, infections, total IgE, IgE response to glycosylated allergens and genetic polymorphisms, indicating that multiple mechanisms may be involved. Our data, showing that exposures to an unhygienic environment and childhood infections modulate immediate allergen skin test reactivity, provide support for the "hygiene hypothesis"

Escore prognóstico precoce após 15 minutos do tratamento da asma aguda na sala de emergência

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