Technique of management of subglottic stenosis

There have been innumerable approaches to the management of subglottic stenosis, which bear testimony to the difficulty in obtaining predictably satisfactory results. Management includes techniques of endoscopic dilation, laser resection, laryngofissure and stenting, and an ingenious array of plastic reconstructions with or without postoperative stenting. On occasion, permanent intubation with a conventional distal tracheotomy or a silicone rubber T tube may be used.     

The efficacy of live attenuated, cold-adapted, trivalent, intranasal influenzavirus vaccine in children

BACKGROUND: Influenzavirus vaccine is used infrequently in healthy children, even though the rates of influenza in this group are high. We conducted a multicenter, double-blind, placebo-controlled trial of a live attenuated, cold-adapted, trivalent influenzavirus vaccine in children 15 to 71 months old. METHODS: Two hundred eighty-eight children were assigned to receive one dose of vaccine or placebo given by intranasal spray, and 1314 were assigned to receive two doses approximately 60 days apart. The strains included in the vaccine were antigenically equivalent to those in the inactivated influenzavirus vaccine in use at the time. The subjects were monitored with viral cultures for influenza during the subsequent influenza season. A case of influenza was defined as an illness associated with the isolation of wild-type influenzavirus from respiratory secretions. RESULTS: The intranasal vaccine was accepted and well tolerated. Among children who were initially seronegative, antibody titers increased by a factor of four in 61 to 96 percent, depending on the influenza strain. Culture-positive influenza was significantly less common in the vaccine group (14 cases among 1070 subjects) than the placebo group (95 cases among 532 subjects). The vaccine efficacy was 93 percent (95 percent confidence interval, 88 to 96 percent) against culture-confirmed influenza. Both the one-dose regimen (89 percent efficacy) and the two-dose regimen (94 percent efficacy) were efficacious, and the vaccine was efficacious against both strains of influenza circulating in 1996-1997, A(H3N2) and B. The vaccinated children had significantly fewer febrile illnesses, including 30 percent fewer episodes of febrile otitis media (95 percent confidence interval, 18 to 45 percent; P<0.001). CONCLUSIONS: A live attenuated, cold-adapted influenzavirus vaccine was safe, immunogenic, and effective against influenza A(H3N2) and B in healthy children.     

Factors involved in Schistosoma mansoni infection in rural areas of northeast Brazil

Two contiguous villages in Tracunhaém county (State of Pernambuco), endemic for schistosomiasis, were studied: Itapinassu (138 inhabitants) and S?o Joaquim (91 inhabitants). Agriculture predominates in the former region while ceramics is the main activity in the latter. Although no statistical difference was found regarding prevalence, severe infection (> 400 epg) predominated in Itapinassu, probably related to the kind of occupation. No association was found between parasite burden and severity of disease, in spite of the high infection rates for Schistosoma mansoni in both communities (approx. 60%). Typical epidemiological features of schistosomiasis such as age-related prevalences and intensities of infection (high in children, low in adults) were also mutual characteristics. Nutritional status determined through anthropometric evaluation was carried out by measuring specific anthropometric indicators. A deficit of energy intake, as well as vitamin A and riboflavin deficiencies were detected. The prevalence of moderate or severe undernutrition in patients under 18 years old was 21.9% in Itapinassu and 24.1% in S?o Joaquim. In this group an association was found between prevalence of schistosomiasis and chronic undernutrition. Similarly, for patients over 18 year old the prevalence of undernutrition was higher than 20%. However, in this case no association between nutritional status and either prevalence of schistosomiasis or parasite burden could be detected. The two communities had not been treated for eight years.     

Temporal relation of ATP-sensitive potassium-channel activation and contractility before cardioplegia

BACKGROUND: Pharmacologic treatment using potassium-channel openers (PCOs) before cardioplegic arrest has been demonstrated to provide beneficial effects on left ventricular performance with subsequent reperfusion and rewarming. However, the PCO treatment interval necessary to provide protective effects during cardioplegic arrest remains to be defined. The present study was designed to determine the optimum period of PCO treatment that would impart beneficial effects on left ventricular myocyte contractility after simulated cardioplegic arrest. METHODS: Left ventricular porcine myocytes were assigned randomly to three groups: (1) normothermic control = 37 degrees C for 2 hours; (2) cardioplegia = K+ (24 mEq/L) at 4 degrees C for 2 hours followed by reperfusion and rewarming; and (3) PCO and cardioplegia = 1 to 15 minutes of treatment with the PCO aprikalim (100 micromol/L) at 37 degrees C followed by hypothermic (4 degrees C) cardioplegic arrest and subsequent rewarming. Myocyte contractility was measured after rewarming by videomicroscopy. A minimum of 50 myocytes were examined at each treatment and time point. RESULTS: Myocyte velocity of shortening was reduced after cardioplegic arrest and rewarming compared with normothermic controls (63+/-3 microm/s versus 32+/-2 microm/s, respectively; p < 0.05). With 3 minutes of PCO treatment, myocyte velocity of shortening was improved after cardioplegic arrest to values similar to those of normothermic controls (56+/-3 microm/s). Potassium channel opener treatment for less than 3 minutes did not impart a protective effect, and the protective effect was not improved further with more prolonged periods of PCO treatment. CONCLUSIONS: A brief interval of PCO treatment produced beneficial effects on left ventricular myocyte contractile function in a simulated model of cardioplegic arrest and rewarming. These results suggest that a brief period of PCO treatment may provide a strategy for myocardial protection during prolonged cardioplegic arrest in the setting of cardiac operation.     

Gallium-67 (Ga-67) scintigraphy in tuberculosis and Mycobacterium avium-M. intracellulare infections in patients with HIV infections

BACKGROUND: Diagnosis of mycobacterioses in HIV infected patients is sometimes difficult because of atypical findings. The aim of this study was to assess the utility of gallium scintigraphy in diagnosis of AIDS related mycobacterioses in patients with fever of unknown origin. PATIENTS AND METHODS: We retrospectively reviewed the scans of 220 HIV(+) patients with fever (176 males [80%] and 44 females) who were evaluated with conventional diagnostic procedures at least of a week before. RESULTS: Gallium scintigraphy was positive in 114 patients (51%) and negative in 106 (49%). Mycobacteria were isolated in 83 patients (38%), 75 of these patients (90%) had a positive scintigraphy (sensitivity 90%; specificity 71%). Positive predictive value was 66% and negative predictive value was 92%. Mycobacterium avium-M. intracellulare (MAI) and M. tuberculosis were diagnosed in 22 (29%) and 53 (71%) HIV(+) patients, respectively. Seventy one (94%) of 75 patients with mycobacterioses had gallium uptake in at least two localizations. CONCLUSIONS: 67Ga scintigraphy is very useful in HIV(+) patients with fever of unknown origin. A negative gallium scintigraphy makes unlikely the diagnosis of mycobacterioses.