Intrathecal K free light chain synthesis in multiple sclerosis at clinical onset associates with local IgG production and improves the diagnostic value of cerebrospinal fluid examination.

BACKGROUND: The pathological significance and the diagnostic usefulness of intrathecal κ and λ free light chain (FLC) synthesis in Multiple Sclerosis (MS) are debated. METHODS: Paired cerebrospinal fluid (CSF) and serum specimens from 70 relapsing remitting MS (RRMS), 40 with and 30 without CSF restricted IgG Oligoclonal Band (IgGOB), and 37 from healthy controls (HC) were analyzed. IgG, IgM, κFLC and λFLC concentrations and indexes were evaluated. All RRMS performed MRI to estimate white and grey matter (WM) pathology. RESULTS: In HC, no intrathecal κ or λ FLC synthesis was found, and κFLC and λFLC Indexes were reciprocally correlated (r = 0.67, p < 0.001). In RRMS, intrathecal κFLC or λFLC synthesis was demonstrated in respectively 66% and 43% of the cases, the Qκ/λ ratio was significantly higher compared to HC (17.0 ±â€¯31.3 vs 0.79 ±â€¯0.20, p < 0.001) and the correlation between κFLC Index and λFLC Index was weak (r:0.38, p < 0.05). Intrathecal IgG synthesis was associated with κFLC Index (IgG Index: r2 = 0.53, ß = 0.73, p < 0.001; IgGLOC: r2 = 0.37, ß = 0.61, p < 0.001; IgGIF: r2 = 0.69, ß = 0.83, p < 0.001), but not with λFLC Index, while intrathecal IgM synthesis correlated with λFLC Index (IgM Index: r = 0.41, p < 0.001; IgMLOC: r = 0.34, p < 0.005; IgMIF: r = 0.45, p < 0.001), but not with κFLC Index. 26% of RRMS patients without CSF-restricted IgGOB had increased κFLCLOC. Finally, no associations were observed between any CSF and MRI parameters. CONCLUSIONS: The demonstration of intrathecal κFLC synthesis may further improve the diagnostic usefulness of CSF examination in RRMS. The marked increased in Qκ/λ further suggests a deregulated B-cell activation in MS pathology.

Risk factors and opportunities for prevention of early-onset neonatal sepsis: a multicenter case-control study.

BACKGROUND: Early-onset group B streptococcal (GBS) prevention efforts are based on targeted use of intrapartum antibiotic prophylaxis (IAP); applicability of these prevention efforts to infections caused by other organisms is not clear. METHODS: Multicenter surveillance during 1995 to 1996 for culture-confirmed, early-onset sepsis in an aggregate of 52 406 births; matched case-control study of risk factors for GBS and other sepsis. RESULTS: Early-onset disease occurred in 188 infants (3.5 cases per 1000 live births). GBS (1.4 cases per 1000 births) and Escherichia coli (0.6 cases per 1000 births) caused most infections. GBS sepsis less often occurred in preterm deliveries compared with other sepsis. Compared with gestation-matched controls without documented sepsis, GBS disease was associated with intrapartum fever (matched OR, 4.1; CI, 1.2-13.4) and frequent vaginal exams (matched OR, 2.9; CI, 1.1-8. 0). An obstetric risk factor-preterm delivery, intrapartum fever, or membrane rupture >/=18 hours-was found in 49% of GBS cases and 79% of other sepsis. IAP had an adjusted efficacy of 68.2% against any early-onset sepsis. Ampicillin resistance was evident in 69% of E coli infections. No deaths occurred among susceptible E coli infections, whereas 41% of ampicillin-resistant E coli infections were fatal. Ninety-one percent of infants who developed ampicillin-resistant E coli infections were preterm, and 59% of these infants were born to mothers who had received IAP. CONCLUSIONS: Either prenatal GBS screening or a risk-based strategy could potentially prevent a substantial portion of GBS cases. Sepsis caused by other organisms is more often a disease of prematurity. IAP seemed efficacious against early-onset sepsis. However, the severity of ampicillin-resistant E coli sepsis and its occurrence after maternal antibiotics suggest caution regarding use of ampicillin instead of penicillin for GBS prophylaxis.

Effects of hospital policies based on 1996 group B streptococcal disease consensus guidelines. The Active Bacterial Core Surveillance Team.

OBJECTIVE: To determine whether the 1996 consensus guidelines for prevention of early-onset group B streptococcal disease developed by the Centers for Disease Control and Prevention, ACOG, and the American Academy of Pediatrics are affecting obstetric practice and disease occurrence. METHODS: Personnel in hospitals with obstetric services in seven surveillance areas completed surveys about their programs, patient populations, and group B streptococcal disease prevention policies. Survey results were linked to group B streptococcal disease cases identified by active surveillance in 1996 and 1997. An early onset case was defined as a case in which group B streptococci were isolated from a sterile site in the 1st 6 days of life. The number of cases in 1996 and 1997 were compared using a paired t test. Linear regression was used to assess hospital characteristics associated with group B streptococcal disease cases. RESULTS: Of 177 hospitals, 165 (93%) responded, and 96 (58%) of those had group B streptococcal disease prevention policies. Hospitals that established or revised their policies in 1996 had a lower mean number of cases in 1997 than in 1996 (0.58 versus 1.29, P = .006). Linear regression analysis, controlling for number of births, indicated that a hospital's having more black mothers and location in particular states were associated with more cases of disease. Citing the 1996 ACOG reference as the source for hospital group B streptococcal disease prevention policy was associated with fewer cases of group B streptococcal disease (P = .038). CONCLUSION: The publication and adoption of the guidelines were associated with decreasing occurrence of group B streptococcal disease.

Association between colonization with group B streptococci during pregnancy and preterm delivery among Danish women.

OBJECTIVE: We studied the relationship between group B streptococcal colonization and preterm delivery. STUDY DESIGN: In this prospective study at a single hospital in Odense, Denmark, cervicovaginal cultures were obtained at < or = 24 weeks' gestation from all the women, at delivery from women with preterm deliveries, and from a random sample of women delivering at term. RESULTS: In 2846 singleton births, there was no significant association between group B streptococcal colonization at

Group B streptococcal disease in the era of intrapartum antibiotic prophylaxis.

BACKGROUND: Group B streptococcal infections are a leading cause of neonatal mortality, and they also affect pregnant women and the elderly. Many cases of the disease in newborns can be prevented by the administration of prophylactic intrapartum antibiotics. In the 1990s, prevention efforts increased. In 1996, consensus guidelines recommended use of either a risk-based or a screening-based approach to identify candidates for intrapartum antibiotics. To assess the effects of the preventive efforts, we analyzed trends in the incidence of group B streptococcal disease from 1993 to 1998. METHODS: Active, population-based surveillance was conducted in selected counties of eight states. A case was defined by the isolation of group B streptococci from a normally sterile site. Census and live-birth data were used to calculate the race-specific incidence of disease; national projections were adjusted for race. RESULTS: Disease in infants less than seven days old accounted for 20 percent of all 7867 group B streptococcal infections. The incidence of early-onset neonatal infections decreased by 65 percent, from 1.7 per 1000 live births in 1993 to 0.6 per 1000 in 1998. The excess incidence of early-onset disease in black infants, as compared with white infants, decreased by 75 percent. Projecting our findings to the entire United States, we estimate that 3900 early-onset infections and 200 neonatal deaths were prevented in 1998 by the use of intrapartum antibiotics. Among pregnant girls and women, the incidence of invasive group B streptococcal disease declined by 21 percent. The incidence among nonpregnant adults did not decline. CONCLUSIONS: Over a six-year period, there has been a substantial decline in the incidence of group B streptococcal disease in newborns, including a major reduction in the excess incidence of these infections in black infants. These improvements coincide with the efforts to prevent perinatal disease by the wider use of prophylactic intrapartum antibiotics.