Carriage of multidrug-resistant Streptococcus pneumoniae and impact of chemoprophylaxis during an outbreak of meningitis at a day care center

Three cases of meningitis due to multidrug-resistant serotype 14 Streptococcus pneumoniae occurred at a day care center (DCC) over 5 days. Cultures of nasopharyngeal samples were done at the index DCC, 2 comparison DCCs, and a pediatrics practice. Isolates were serotyped and subtyped by pulsed-field gel electrophoresis (PFGE) with SmaI. Pneumococcal carriage rates ranged from 44%-65% at the 3 DCCs and 29% in the pediatrics practice. Carriage of multidrug-resistant serotype 14 S. pneumoniae was noted in 13%-19% of children at the 3 DCCs. An outbreak strain was identified by PFGE at the index DCC and 1 other DCC; a closely related strain was found in the third DCC. Carriage of the outbreak strain was associated with being age 0-24 months, antibiotic use, upper respiratory tract infections, and otitis media. DCC contacts of the ill children were offered chemoprophylaxis with rifampin and clindamycin, which produced a profound but transient decrease in carriage. No additional cases occurred.

Newly recognized focus of La Crosse encephalitis in Tennessee

La Crosse virus is a mosquito-borne arbovirus that causes encephalitis in children. Only nine cases were reported in Tennessee during the 33-year period from 1964-1996. We investigated a cluster of La Crosse encephalitis cases in eastern Tennessee in 1997. Medical records of all suspected cases of La Crosse virus infection at a pediatric referral hospital were reviewed, and surveillance was enhanced in the region. Previous unreported cases were identified by surveying 20 hospitals in the surrounding 16 counties. Mosquito eggs were collected from five sites. Ten cases of La Crosse encephalitis were serologically confirmed. None of the patients had been discharged from hospitals in the region with diagnosed La Crosse encephalitis in the preceding 5 years. Aedes triseriatus and Aedes albopictus were collected at the case sites; none of the mosquitos had detectable La Crosse virus. This cluster may represent an extension of a recently identified endemic focus of La Crosse virus infection in West Virginia.

Congenital varicella-zoster virus infection and Barrett's esophagus

Congenital varicella syndrome is a rare complication of varicella-zoster virus (VZV) infection during pregnancy. An infant was exposed to VZV at 18.5 weeks of gestation and had eye and skin abnormalities at birth and persistent feeding difficulties, prompting esophageal biopsies at 12 days and 20 and 20.5 months of age. Esophageal tissues demonstrated specialized intestinal metaplasia (Barrett's esophagus). VZV DNA (in situ hybridization) and proteins (immunohistochemistry and polymerase chain reaction) were found in esophageal epithelial cells adjacent to the Barrett's lesion. Immediate-early 63 protein (IE63) of VZV was demonstrated in the day 12 specimen, and IE62 and the late VZV glycoprotein E (gE) were found in the 20-month specimen. Clinical and endoscopic improvement followed fundoplication and acyclovir therapy, but VZV DNA and IE62 persisted in esophageal tissue. These findings associate VZV with specialized intestinal metaplasia within the esophagus and suggest a novel site for either latent or active VZV infection.

Handwashing and glove use in a long-term-care facility

OBJECTIVES

To determine glove use and handwashing practices, the factors associated with infection control practices, and the frequency of potential microbial transmission in a long-term-care facility (LTCF).

DESIGN

Observational study of 230 staff-resident interactions in an LTCF. We recorded resident characteristics, type of activity, staff credentials, and movements of the staff member's hands, then used the LTCF's guidelines to judge appropriateness of glove use and handwashing.

SETTING

255-bed, university-based LTCF in Baltimore, Maryland.

PARTICIPANTS

A systematic sample of staff-resident interactions.

RESULTS

Gloves were worn in 139 (82%) of 170 interactions when indicated, but changed appropriately in only 1 (16%) of 132. Hands were washed when needed before an interaction in 27%, during an interaction in 0%, and after an interaction in 63%. Gloves were less likely to be used when caring for residents with gastrostomy tubes compared with other residents (relative risk, 0.85; 95% confidence interval, 0.73-0.98). Guidelines were followed more frequently during wound care than during other activities. Microbial transmission potentially could have occurred in 158 (82%) of 193 evaluable interactions.

CONCLUSIONS

We documented marked deficiencies in glove and handwashing, demonstrated the possible impact of these deficiencies, and identified factors associated with inadequate handwashing and glove use. This information can be used in future educational and research efforts to improve infection control practices.

Risk factors for nasopharyngeal carriage of resistant Streptococcus pneumoniae and detection of a multiply resistant clone among children living in the Yukon-Kuskokwim Delta region of Alaska

BACKGROUND

Children < 2 years old living in the Yukon-Kuskokwim Delta (YKD) region of Alaska have one of the highest pneumococcal bacteremia rates of in the world.

METHODS

To determine the prevalence of and risk factors for infection with intermediate or resistant Streptococcus pneumoniae in the YKD, we cultured nasopharyngeal secretions of healthy children < or = 5 years old, reviewed their hospital records and administered questionnaires to accompanying parents.

RESULTS

Of 185 children evaluated we obtained 95 pneumococcal isolates; drug susceptibility patterns and serotyping results were available for 92. Of these, 33 (36%) were intermediate or resistant to at least one drug class tested; 27 isolates were intermediate (minimum inhibitory concentration 0.1 to 1.0 mg/l) and none were resistant to penicillin. Compared with other isolates, capsular serotype 6B isolates were more likely to be intermediate or resistant to at least one drug (relative risk, 5.3; P < 0.001) and to more than one drug (relative risk, 17.0; P < 0.001). The majority of 6B isolates had identical pneumococcal surface protein A patterns. Carriage of intermediate or resistant pneumococcus was associated with age < 2 years (relative risk, 3.0; P < 0.001) but not with antibiotic use or other evaluated risk factors.

CONCLUSIONS

Young age but not antibiotic use was associated with carriage of intermediate or resistant S. pneumoniae in the YKD region of Alaska. Much of the intermediate or resistant pneumococcus in the YKD may have resulted from the proliferation of a single capsular serotype 6B clone.

Transmission of multidrug-resistant Mycobacterium tuberculosis among persons exposed in a medical examiner's office, New York

OBJECTIVE

To determine the prevalence of and risk factors for having a positive tuberculin skin test (TST) result among employees at a medical examiner's office (MEO).

DESIGN

Cohort study, environmental investigation.

SETTING

Several employees at a medical examiner's office were found to have positive TST results after autopsies were performed on persons with multidrug-resistant tuberculosis (MDR-TB).

PARTICIPANTS

Employees of the MEO.

RESULTS

Of 18 MEO employees, 5 (28%) had a positive TST result; 2 of these 5 had TST conversions. We observed a trend between TST conversion and participation in autopsies on persons with MDR-TB (2 of 2 converters versus 3 of 13 employees with negative TST; relative risk = 4.3; 95% confidence interval 1.61 to 11.69; P = 0.10). The environmental investigation revealed that the autopsy room was at positive pressure relative to the rest of the MEO and that air from the autopsy room mixed throughout the facility.

CONCLUSIONS

A systematic approach to preventing transmission of Mycobacterium tuberculosis in autopsy suites should include effective environmental controls and routine tuberculin skin testing of employees.

Risk factors for invasive disease caused by Streptococcus pneumoniae among Alaska native children younger than two years of age

Streptococcus pneumoniae causes a significant amount of illness and death from pneumonia, bacteremia and meningitis among children < 2 years of age. No currently available effective vaccine exists to prevent pneumococcal disease in this age group. To identify modifiable risk factors we conducted a retrospective case-control study of 29 Alaska Native residents of Bethel, AK, < 2 years of age who had invasive pneumococcal illness from 1983 to 1992 and 85 controls matched for race, city of residence and date of birth. Data were collected through reviews of medical records and telephone interviews. In matched univariate analysis the following variables were associated with illness at P < or = 0.25 and were included in the multivariate model: at least one prior episode of pneumonia; at least one prior hospitalization; group child care center attendance; at least one tobacco smoker in the household; at least one tobacco chewer in the household; and lack of breast-feeding. Using a conditional multiple logistic regression analysis, we found that group child care center attendance (odds ratio, 98.6; 95% confidence interval, 5.1 to 1920.6) and the presence in the household of at least one person who chewed tobacco (odds ratio, 20.6; 95% confidence interval, 1.4 to 294.5) were independently associated with illness while breast-feeding was protective (odds ratio, 0.1; 95% confidence interval, 0.0 to 1.0). These data suggest that breast-feeding may prevent invasive pneumococcal disease and that strategies for decreasing risks should target children in group child care settings. Further studies are needed to evaluate the interaction of tobacco and pneumococcal illness.

Acute liver injury after protracted seizures in children

Three children were observed to have extensive liver injury following protracted seizures. Two recovered with supportive care and one died from central nervous system complications. When first measured, the levels of aminotransferases were minimally elevated, but they increased to 250 to 8,000 times normal within 12 to 24 h after the seizure episode. They fell to near normal over the next 8 to 11 days in the survivors, and to one sixth of the peak level by 4 days in the patients who died. A percutaneous liver biopsy from one child demonstrated centrolobular necrosis consistent with severe ischemic injury. Common causes for liver dysfunction, including viral hepatitis, drug hepatitis, and Reye syndrome, were excluded on clinical, serologic, and histologic grounds. We reason that hepatic injury resulted from ischemia. We speculate that prior treatment with anticonvulsants, which are capable of inducing mixed-function oxidases in the liver, aggravated the ischemia-reperfusion injury by increasing the production of reactive oxygen intermediates and reducing cytoprotective mechanisms. Prevention of such injury should be directed toward control of seizures and early respiratory support when seizures occur, not restructuring medication regimens.