Immune-globulin prophylaxis of respiratory syncytial virus infection in patients undergoing stem-cell transplantation.

Thirty-two patients undergoing allogeneic hematopoietic stem-cell transplantation were given respiratory syncytial virus (RSV) immune globulin (RSVIG) at the time of transplantation and again 3 weeks later. Antibody titers to RSV, human parainfluenza virus 3, measles, and influenza H1N1, H3N2, and B were measured prior to administration of RSVIG and 6 more times over the course of the subsequent 6 weeks. Baseline antiviral titers and increases in antibody after administration of RSVIG were extremely variable for all the viruses. In 18 patients in whom the baseline titers of antibody titers to RSV-F protein were 1:640-1:2048, there was a 7.7-fold initial increase in these titers after the first dose of RSVIG, compared with a 2.1-fold increase in 14 patients with baseline titers of 1:4096-1:20,840; increases in titers of antibody against the other viruses after the first dose of RSVIG reflected similar variability. The subset of patients with the lowest titers appear to receive the greatest benefit from administration of RSVIG.

Dental health and viridans streptococcal bacteremia in allogeneic hematopoietic stem cell transplant recipients.

Viridans streptococci were the most common cause of bacteremia in 61 consecutive myeloablative allogeneic hematopoietic stem cell transplant (HSCT) recipients, occurring in 19 of 31 bacteremic patients (61%) during the period of post-transplant neutropenia. Seven of the 19 had more than one viridans streptococcus in the same blood culture. Twenty isolates from 15 patients were Streptococcus mitis. Most viridans streptococci were resistant to norfloxacin, used routinely for prophylaxis. Comparison of the 19 patients with viridans streptococcal bacteremia with a contemporaneous group of 23 allogeneic HSCT recipients with fever and neutropenia but no identified focus of infection found that patients with viridans streptococcal bacteremia were more likely to have severe intraoral pathology while neutropenic (26% vs 0%) and slightly shorter interval between the last dental procedure and the onset of neutropenia (11 vs 14 days). Poor underlying dental health and the use of norfloxacin thus appear to predispose to viridans streptococcal bacteremia.

A minimum 5.0 ml of sputum improves the sensitivity of acid-fast smear for Mycobacterium tuberculosis.

Detection of acid-fast bacilli (AFB) by sputum smear supports treatment decisions with pulmonary tuberculosis (TB), but smear sensitivity for Mycobacterium tuberculosis is only approximately 45 to 75%. In an effort to increase sensitivity, smears were prepared using a minimum sputum volume of 5.0 ml. Sensitivity of smears during a 39-mo period (n = 1,849) using >/= 5.0 ml of sputum was 92. 0%, significantly greater (p < 0.001) than a sensitivity of 72.5% in a previous 24-mo period (n = 3,486) when all specimens were processed regardless of volume. All new cases of TB (n = 18) were smear-positive with >/= 5.0 ml of sputum before treatment, and all were receiving antituberculosis drugs at hospital discharge. In contrast, significantly fewer new cases of TB (14 of 26, p = 0.002) were positive before treatment when smears were prepared using sputum of any volume, and significantly fewer of these new TB cases (18 of 26, p = 0.03) were receiving treatment at hospital discharge. The eight cases without treatment were smear-negative. These results indicate that acid-fast smear using >/= 5.0 ml of sputum increases sensitivity for M. tuberculosis and accelerates treatment of TB.