While our baseline CABSI rate was comparatively lower than for other institutions, subset analyses identified that hospitalized cancer patients having TEs are at the highest risk for developing CABSIs. Our findings may help to guide improved methods of anticipating and controlling infections in immunocompromised patients.

No abstract

Pneumococcal infections are the most common invasive bacterial infections in children in the United States. The incidence of invasive pneumococcal infections peaks in children younger than 2 years, reaching rates of 228/100,000 in children 6 to 12 months old. Children with functional or anatomic asplenia (including sickle cell disease [SCD]) and children with human immunodeficiency virus infection have pneumococcal infection rates 20- to 100-fold higher than those of healthy children during the first 5 years of life. Others at high risk of pneumococcal infections include children with congenital immunodeficiency; chronic cardiopulmonary disease; children receiving immunosuppressive chemotherapy; children with immunosuppressive neoplastic diseases; children with chronic renal insufficiency, including nephrotic syndrome; children with diabetes; and children with cerebrospinal fluid leaks. Children of Native American (American Indian and Alaska Native) or African American descent also have higher rates of invasive pneumococcal disease. Outbreaks of pneumococcal infection have occurred with increased frequency in children attending out-of-home care. Among these children, nasopharyngeal colonization rates of 60% have been observed, along with pneumococci resistant to multiple antibiotics. The administration of antibiotics to children involved in outbreaks of pneumococcal disease has had an inconsistent effect on nasopharyngeal carriage. In contrast, continuous penicillin prophylaxis in children younger than 5 years with SCD has been successful in reducing rates of pneumococcal disease by 84%. Pneumococcal polysaccharide vaccines have been recommended since 1985 for children older than 2 years who are at high risk of invasive disease, but these vaccines were not recommended for younger children and infants because of poor antibody response before 2 years of age. In contrast, pneumococcal conjugate vaccines (Prevnar) induce proposed protective antibody responses (>.15 microg/mL) in >90% of infants after 3 doses given at 2, 4, and 6 months of age. After priming doses, significant booster responses (ie, immunologic memory) are apparent when additional doses are given at 12 to 15 months of age. In efficacy trials, infant immunization with Prevnar decreased invasive infections by >93% and consolidative pneumonia by 73%, and it was associated with a 7% decrease in otitis media and a 20% decrease in tympanostomy tube placement. Adverse events after the administration of Prevnar have been limited to areas of local swelling or erythema of 1 to 2 cm and some increase in the incidence of postimmunization fever when it is given with other childhood vaccines. Based on data in phase 3 efficacy and safety trials, the US Food and Drug Administration has provided an indication for the use of Prevnar in children younger than 24 months.

No abstract

No abstract

The incidence of invasive infection due to Streptococcus pneumoniae is 6.9 infections per 100 patient-years among children with sickle cell anemia (SS genotype) who are less than 5 years of age; this rate is 30-100 times that which would be expected in a healthy population of this age. Splenic dysfunction is the major contributor to the increased risk. Postulated abnormalities of immunologic defense mechanisms, including synthesis of polyclonal IgG and IgM, the alternative complement pathway, opsonic activity, and T and B cell interaction, may also enhance risk. Preceding or concomitant viral infection is suspected of predisposing to pneumococcal infection, but no definitive data are available. The most prevalent pneumococcal serotypes causing disease in this setting include types 6, 14, 18, 19, and 23; these same serotypes are most frequently involved in "vaccine failure." Current evidence demonstrates only modest protective efficacy for contemporary pneumococcal vaccines in young patients with sickle cell anemia; thus alternative vaccines are required. Convincing evidence for a protective effect of antibiotic prophylaxis has been obtained in limited time trials. However, presently used prophylactic regimens pose problems related to compliance and provide imperfect protection; moreover, their optimal duration remains unknown.

We evaluated 191 consecutive adults with pulmonary tuberculosis in order to develop methods to determine which patients should be initially hospitalized. Using stepwise discriminant analysis, we found the six factors that were most strongly associated with an unfavorable short-term outcome (respiratory failure or death): lymphopenia, advanced age, concomitant smear-positive extrapulmonary tuberculosis, alcoholism, a high percentage of neutrophils on the differential white blood cell count, and lack of radiographic evidence of cavitation. We derived a scoring system incorporating these variables and separated patients into high- and low-risk groups. The system was prospectively validated by applying it to a separate group of 179 patients. Lymphocyte-transformation tests in 32 patients revealed an association between clinical markers of poor prognosis and minimal lymphocyte proliferation to a heat-killed strain of Mycobacterium tuberculosis.

Staphylococcal gingival flora was characterized in cultures from 135 dogs. Staphylococcus intermedius was isolated in 39% of the cultures, S. aureus was isolated in 10%, and both were isolated in 2.0%. S. aureus was isolated more often from dogs of working breeds with weights of >40 lb (ca. 18 kg) and with outdoor habitats than was S. intermedius, which was associated with dogs of nonworking breeds with weights of <40 lb and indoor habitats. S. intermedius was distinguished from S. aureus by the following characteristics: coagulation of rabbit plasma at 4 h (26 versus 100%, respectively), hemolysis of sheep blood at 24 h (30 versus 79%, respectively), and mannitol fermentation at 24 h (4 versus 93%, respectively). A clear separation of the two species was apparent only with the acetoin (modified Voges-Proskauer) reaction (100% of the S. aureus isolates versus 0% of the S. intermedius isolates) and P-galactosidase activity on the API Staph-Ident strip (0% of the S. aureus isolates and 100% of the S. intermedius isolates). Susceptibilities of S. intermedius and S. aureus were 72 and 7%, respectively, to penicillin G, and 100% of both species to oxacillin. Fourteen previously collected strains of coagulase-positive staphylococci from infected canine-inflicted human wounds were reanalyzed; 3 of 14 (21 %) isolates were S. intermedius. We conclude that S. intermedius is a common canine gingival flora and is responsible for some canine-inflicted human wound infections, thus representing a newly recognized zoonotic pathogen.