Fosamprenavir with Ritonavir Pharmacokinetics during Pregnancy.

The purpose of this study was to evaluate the pharmacokinetics of ritonavir-boosted fosamprenavir during pregnancy and postpartum. Amprenavir (the active moiety of fosamprenavir) and ritonavir intensive pharmacokinetic evaluations were performed at steady state during the second and third trimesters of pregnancy and postpartum. Plasma concentrations of amprenavir and ritonavir were measured using high-performance liquid chromatography. The target amprenavir area under the concentration-versus-time curve (AUC) was higher than the 10th percentile (27.7 µg · h/ml) of the median area under the curve for ritonavir-boosted fosamprenavir in adults receiving twice-daily fosamprenavir-ritonavir at 700 mg/100 mg. Twenty-nine women were included in the analysis. The amprenavir AUC from time zero to 12 h (AUC0-12) was lower (geometric mean ratio [GMR], 0.60 [confidence interval {CI}, 0.49 to 0.72] [P < 0.001]) while its apparent oral clearance was higher (GMR, 1.68 [CI, 1.38 to 2.03] [P < 0.001]) in the third trimester than postpartum. Similarly, the ritonavir AUC0-12 was lower in the second (GMR, 0.51 [CI, 0.28 to 0.91] [P = 0.09]) and third (GMR, 0.72 [CI, 0.55 to 0.95] [P = 0.005]) trimesters than postpartum, while its apparent oral clearance was higher in the second (GMR, 1.98 [CI, 1.10 to 3.56] [P = 0.06]) and third (GMR, 1.38 [CI, 1.05 to 1.82] [P = 0.009]) trimesters than postpartum. The amprenavir area under the curve exceeded the target for 6/8 (75%) women in the 2nd trimester, 18/28 (64%) in the 3rd trimester, and 19/22 (86.4%) postpartum, and the trough concentrations (Cmin) of amprenavir were 4- to 16-fold above the mean amprenavir-protein-adjusted 50% inhibitory concentration (IC50) of 0.146 µg/ml. Although amprenavir plasma concentrations in women receiving ritonavir-boosted fosamprenavir were lower during pregnancy than postpartum, the reduced amprenavir concentrations were still above the exposures needed for viral suppression.

Lower Newborn Bone Mineral Content Associated With Maternal Use of Tenofovir Disoproxil Fumarate During Pregnancy.

BACKGROUND: Fetal bone effects of maternal tenofovir use have not been well studied. We sought to compare whole-body bone mineral content (BMC) of newborns exposed vs not exposed to tenofovir in utero. METHODS: We enrolled participants from April 2011 to June 2013 at 14 US clinical sites. Singleton infants of women with human immunodeficiency virus (HIV) infection who took tenofovir in late pregnancy (tenofovir-exposed) or no tenofovir during pregnancy (tenofovir-unexposed) were enrolled during late pregnancy or within 72 hours of birth. Infants born before 36 weeks gestation or with confirmed HIV infection were excluded. Whole-body BMC was measured in the first month of life and compared with that of the tenofovir-exposed and tenofovir-unexposed newborns, unadjusted and adjusted for covariates. RESULTS: Seventy-four tenofovir-exposed and 69 tenofovir-unexposed infants had evaluable BMC measurements. Tenofovir-exposed mothers were more likely to be married (31% vs 22%; P = .04) and to use boosted protease inhibitors (84% vs 62%; P = .004). Tenofovir-exposed newborns did not differ from unexposed newborns on mean gestational age (38.2 vs 38.1 weeks) or mean length (-0.41 vs -0.18) or weight (-0.71 vs -0.48) Z-scores. The mean (standard deviation) BMC of tenofovir-exposed infants was 12% lower than for unexposed infants (56.0 [11.8] vs 63.8 [16.6] g; P = .002). The adjusted mean bone mineral content was 5.3 g lower (95% confidence interval, -9.5, -1.2; P = .013) in the tenofovir-exposed infants. CONCLUSIONS: Maternal tenofovir use is associated with significantly lower neonatal BMC. The duration and clinical significance of this finding should be evaluated in longitudinal studies. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov NCT01310023.

Mucormycosis in children with cancer and hematopoietic cell transplant-A single center cohort study.

Although mucormycosis is an important cause of morbidity and mortality in children with cancer, our understanding of the typical characteristics of these infections is incomplete. We reviewed all cases of mucormycosis diagnosed at a single pediatric cancer center over 5 decades to identify the clinical features of mucormycosis in pediatric oncology patients and to identify risk factors for mortality. There were 44 cases of mucormycosis diagnosed between 1970-2019. Most patients (89%) had hematological malignancies and a history of prolonged and severe neutropenia (91%). In this series, hyperglycemia and exposure to corticosteroids were common. Pulmonary (36%) and disseminated infections (32%) were most common; rhino-orbital-cerebral infections were relatively infrequent (11%). Rhizopus spp. was the most common etiological agent (40%) followed by Mucor spp. (31%), and Cunninghamella spp. (19%). Overall mortality was 44% and 51% and attributable mortality was 39% and 41% at the end of antifungal therapy and end of follow up, respectively. Attributable mortality fell to 18% in 2010-2019, from 58-60% in previous decades; adjunctive surgery was associated with decreased mortality. Mortality remains unacceptably high despite aggressive antifungal therapy and adjunctive surgery, suggesting novel therapeutic strategies are needed.

Posaconazole therapeutic drug monitoring in pediatric patients and young adults with cancer.

BACKGROUND: Limited information exists regarding the use of posaconazole for treating systemic fungal infections in children, adolescents, and young adults with cancer. At St. Jude Children's Research Hospital, the recommended posaconazole dose in patients weighing less than 34 kg is 18-24 mg/kg daily, given in 4 divided doses. For patients aged 13 years or older or those weighing 34 kg or more, the recommended dose is 800 mg daily, given orally in 4 divided doses. OBJECTIVE: To determine whether the current posaconazole dosing guidelines achieve target posaconazole plasma concentrations of 0.7 µg/mL or greater. METHODS: This retrospective clinical study examined data from patients who received treatment-dose posaconazole and had at least 1 posaconazole plasma concentration measurement. RESULTS: Data from 33 patients who received posaconazole for the treatment of fungal infections were analyzed. The median age of patients was 11.5 years (range 0.5-23.2). Twenty-one of 33 patients (63.6%) had posaconazole concentrations of 0.7 µg/mL or greater (median 1.4; range 0.7-2.98) at the first measurement. The median posaconazole dosage referenced to total body weight in these patients was 20 mg/kg/day. Patients with concentrations less than 0.7 µg/mL (median 0.4; range 0.025-0.69) received lower posaconazole dosages when referenced to body weight (median 12.9 mg/kg/day; p = 0.02). Of the 12 patients with concentrations less than 0.7 µg/mL, 7 (58.3%) were aged 13 years or older. CONCLUSIONS: The current dosing approach for posaconazole yielded therapeutic plasma concentrations more frequently in patients younger than 13 years than in those 13 years or older. This difference may be related to the practice of capping adolescent and young adult doses at the suggested maximum adult daily dose. Therefore, we recommend weight-based dosing in all pediatric, adolescent, and young adult patients with cancer, with routine therapeutic drug monitoring to ensure adequate concentrations.

Prevention of Mother-to-Child Human Immunodeficiency Virus Transmission in Resource-Limited Countries.

The first pediatric AIDS cases were reported in 1982. A decade later, the World Health Organization estimated there were more than 500,000 pediatric AIDS cases resulting from mother-to-child transmission, 90% of which were in sub-Saharan Africa. Although the rate of new infections globally has been cut in half since the peak of the pandemic, human immunodeficiency virus (HIV) remains a public health threat, and rates of new infections continue to increase in some regions. Mother-to-child transmission of HIV has now been virtually eliminated in many parts of the world but remains an issue in resource-limited countries.

Rapid Start of Antiretroviral Therapy in Youth Diagnosed with HIV Infection.

BACKGROUND: Guidelines for the use of antiretroviral agents in adults and adolescents with HIV recommend that antiretroviral therapy (ART) be started as soon as possible. While rapid initiation of ART in adults with HIV has been well-described, there is relatively little information describing this approach for youth. METHODS: On April 1, 2018, St. Jude Children's Research Hospital began offering ART to youth with HIV infection at their first clinic visit. We report the results of a quality improvement initiative that compared patients who offered ART at their first visit to a historical cohort of patients who initiated ART at a subsequent visit. Demographic, HIV biomarker, and visit information were abstracted from medical records, described and compared using univariate statistical methods. RESULTS: There were 124 ART-naive youth (median age 19 years, 91% male, 94% black) first seen during the indicated time period. A total of 54 patients were in the baseline cohort and 70 patients were in the rapid start cohort. 90% of youth in the rapid start cohort started ART on their first clinic visit. Time from first clinic visit to undetectable viral load was significantly higher in the baseline cohort compared with the rapid start cohort (median 54 vs. 41 days; P = 0.01). Retention in care 12 months following the first clinic visit was comparable and overall high (>80%). CONCLUSIONS: Starting ART-naïve youth with HIV infection on ART at their first clinic visit is feasible, has high acceptance, leads to faster viral load suppression, and is associated with high retention in care.

Predictors of Viremia in Postpartum Women on Antiretroviral Therapy.

BACKGROUND: HIV-infected, postpartum women on antiretroviral therapy (ART) have high rates of viremia. We examined predictors of postpartum viremia in the PROMISE study. METHODS: Women with pre-ART CD4 T-cell counts ≥400 cells/mm who started ART during pregnancy were randomized postpartum to continue ART (CTART) or discontinue ART (DCART). Viral load and self-reported adherence were collected every 12 weeks, up to 144 weeks. Women in DCART reinitiated therapy when clinically indicated. Viremia was defined as 2 consecutive viral loads >1000 copies/mL after 24 weeks on ART. Adherence was dichotomized as missing versus not missing ART doses in the past 4 weeks. Predictors of viremia were examined using Cox proportional hazards regression with adherence as a time-varying covariate. RESULTS: Among 802 women in the CTART arm, median age at entry was 27 years and median CD4 T-cell count 696 cells/mm. Of 175 women in CTART with viremia (22%), 141 had resistance data, and 12% had resistance to their current regimen. There was an estimated 0.12 probability of viremia by week 48 and 0.25 by week 144. Predictors of viremia included missed ART doses within the past 4 weeks, younger age, shorter duration of pre-entry ART, and being from the South American/Caribbean region. Of 137 women in DCART who reinitiated therapy, probability of viremia was similar to CTART (0.24 by week 96; 0.27 by week 144). CONCLUSIONS: Rates of postpartum viremia are high and viremia is more likely in younger postpartum women who start ART later in pregnancy. Interventions should target these higher-risk women.

Etiology and clinical course of febrile neutropenia in children with cancer.

BACKGROUND: The etiology, clinical course, and outcome of fever and neutropenia (FN) in children with cancer using the current FN guidelines and diagnostic resources in the United States have not been well described. PATIENTS AND METHODS: Medical records of a randomly selected FN episode per patient during 2004-2005 at a pediatric oncology center were reviewed. Patients were managed as per institutional FN guidelines and blood cultures collected in continuously read BACTEC bottles. RESULTS: Of 337 FN episodes, infection was proven in 86 (25%) and probable in 75 (22%). In all, 177 episodes (53%) were judged fever of unknown origin (FUO). Bacteremia accounted for most (41) of the proven bacterial episodes, with viridans streptococci (13), Pseudomonas spp. (6) and Escherichia coli (6) the most frequently isolated organisms. The median time to positivity of blood cultures was 12 hours (range, 5.4-143.7) with 93% positive within 24 hours of incubation. Viral pathogens were identified in 29 (34%) episodes. Compared with other patients, those with FUO had shorter median duration of fever (0.5 vs. 2.0 d; P<0.0001) and hospitalization (3 vs. 6 d; P<0.0001), longer median duration since last chemotherapy (6.0 vs. 4.0 d; P=0.01), and were less likely to have a diagnosis of acute myelogenous leukemia (11% vs. 22%; P=0.009) or develop a clinical complication (5.1% vs. 24.4%; P<0.0001). CONCLUSIONS: Despite currently available diagnostic resources, the majority of patients with FN have FUO marked by a low rate of clinical complications and no infection-related mortality. Emergence of viridans streptococci as the most common blood isolate has affected FN treatment recommendations. Study findings will help further development of strategies for risk stratified management of fever with neutropenia in pediatric patients.

Acute necrotizing ulcerative gingivitis and bacteremia caused by Stenotrophomonas maltophilia in an immunocompromised host.

An 8-year-old girl with leukemia developed acute necrotizing ulcerative gingivitis with Stenotrophomonas maltophilia and herpes simplex virus. Progression to bacteremia with pathologic evidence of osteomyelitis occurred despite appropriate antimicrobial therapy. This case highlights the importance of prompt recognition, debridement and appropriate therapy in immunocompromised patients with acute necrotizing ulcerative gingivitis.

Newer treatments for fungal infections.

Invasive fungal infections are a significant cause of morbidity and mortality among immunocompromised cancer patients, and until recently, treatment options have been limited. The poor outcomes of these infections, and the increased incidence of disease, particularly due to resistant and less common fungal isolates, necessitate the development of new agents. Antifungal drug development had been a slow process since the release of amphotericin B over 40 years ago. However, since 1995, six new systemic antifungals have been approved: three lipid formulations of amphotericin B, the initial second-generation triazole, and the first two approved agents in a new class of antifungals with a novel mechanism of action, the echinocandins. These newer agents, and several others currently in development, offer improved tolerability and safety profiles and extend the spectrum of coverage to resistant and less-common fungal infections. The authors describe each of these new compounds and discuss how they fit into the overall management of fungal infections in patients with cancer.

A Prospective, International Cohort Study of Invasive Mold Infections in Children.

BACKGROUND: Invasive mold infections (IMIs) are a leading cause of mortality in immunocompromised children, yet there has never been an international epidemiologic investigation of pediatric IMIs. METHODS: This international, prospective cohort study was performed to characterize the epidemiology, antifungal therapy, and outcomes of pediatric IMIs. Children (≤18 years) with proven or probable IMIs were enrolled between August 2007 and May 2011 at 22 sites. Risk factors, underlying diagnoses, and treatments were recorded. Outcomes were assessed at 12 weeks after diagnosis using European Organization for Research and Treatment of Cancer/Mycoses Study Group response criteria. RESULTS: One hundred thirty-one pediatric patients with IMIs were enrolled; the most common IMI was invasive aspergillosis ([IA] 75%). Children with IA and those with other types of IMIs had similar underlying risk factors, except that children with IMIs caused by non-Aspergillus species were more likely to have received mold-active antifungal agents preceding diagnosis. The most commonly used antifungal classes after diagnosis were triazoles (82%) and polyenes (63%). Combination therapy was used in 53% of patients. Use of combination therapy was associated with an increased risk of adverse events (risk ratio, 1.98; 95% confidence interval, 1.06-3.68; P = .031), although there was no detectable difference in outcome. CONCLUSIONS: Although risk factors for IMIs are similar across specific subtypes, preceding antifungal therapy may be an important modifier. Combination antifungal therapy requires further study to determine its true risks and benefits.

Pneumonitis associated with Ureaplasma urealyticum in children with cancer.

We describe 3 pediatric patients with cancer who had clinical and radiographic evidence of pneumonitis and for whom cultures of bronchoalveolar lavage fluid specimens yielded Ureaplasma urealyticum. Two of the patients died; for the surviving patient, clinical improvement coincided temporally with administration of erythromycin. Immunocompromised patients with pneumonitis of unclear etiology should have respiratory secretions cultured for mycoplasmas and should receive empiric therapy that includes a macrolide antibiotic.

Voriconazole prophylaxis in children with cancer: changing outcomes and epidemiology of fungal infections.

BACKGROUND: Invasive mould infections are a significant cause of morbidity and mortality in pediatric cancer patients, particularly in those undergoing aggressive myeloablative chemotherapy. Voriconazole has been described as an appropriate and effective prophylactic agent in adults with cancer. METHODS: We compared the etiology, predisposing factors and outcomes of invasive mould infection in patients treated for acute myeloid leukemia before and after implementation of voriconazole prophylaxis in a pediatric cancer center. RESULTS: We observed no difference in the number of invasive mould infection between groups. However, isolated organisms were markedly different, with a shift from aspergillosis to phaeohyphomycosis after the implementation of voriconazole prophylaxis. Survival at 90 days was improved in patients receiving voriconazole prophylaxis (P = 0.05). We did not identify a significant increase in the incidence of zygomycosis associated with routine use of voriconazole prophylaxis. CONCLUSIONS: Voriconazole prophylaxis was associated with improved survival in pediatric patients with acute myeloid leukemia, although other factors may be involved. Voriconazole prophylaxis was associated with a marked change in the pattern of mould infections, with a significant reduction in aspergillosis.

Prevalence of congenital anomalies in infants with in utero exposure to antiretrovirals.

BACKGROUND: Although use of efficacious interventions, including antiretrovirals (ARVs), has dramatically reduced the rate of mother-to-child transmission of human immunodeficiency virus, the safety of in utero ARV exposure remains of concern. METHODS: Data regarding 1112 infants enrolled in the International Maternal Pediatric Adolescent AIDS Clinical Trials Group protocol P1025 born between 2002 and 2007 were analyzed for this study. Congenital anomalies were classified based on the Metropolitan Atlanta Congenital Defects Program guidelines. Associations between congenital anomalies and timing of first in utero exposure to ARVs were evaluated by logistic regression analysis. RESULTS: Congenital anomalies were identified and confirmed in 61 of the 1112 infants, resulting in a prevalence of 5.49/100 live births (95% confidence interval, 4.22-6.99). Among the 80 anomalies identified, the organ systems involved included cardiovascular (n = 33), musculoskeletal (n = 15), renal (n = 9), genitourinary (n = 6), craniofacial (n = 4), and central nervous system (n = 2). First trimester exposure to efavirenz was associated with a significantly increased risk of congenital anomalies (odds ratio, 2.84; 95% confidence interval, 1.13-7.16). No significant associations were observed between exposure to other individual ARVs or classes of ARVs started at any time during pregnancy and infant congenital anomalies. CONCLUSIONS: The observed rate of congenital anomalies in this cohort is higher than previously reported for the general population, but it is consistent with rates observed in other recent studies of children born to human immunodeficiency virus-infected women. Cardiovascular anomalies occurred most frequently. With the exception of a known teratogen (efavirenz), no statistically significant associations between in utero exposure to ARVs and congenital anomalies were identified.

Risk prediction in pediatric cancer patients with fever and neutropenia.

BACKGROUND: To identify predictors for 2 risk measures-"proven invasive bacterial infection or culture-negative sepsis (IBD)" and "clinical complications (CC)"-in pediatric cancer patients with fever and neutropenia (FN). METHODS: Records of 390 patients with FN hospitalized over 2 years were reviewed. For the 332 who met inclusion criteria, one FN episode was randomly selected. Independent predictors at presentation were analyzed using multiple regression models. Optimal cut-off risk prediction scores were determined. These models were validated by bootstrap analysis. RESULTS: Patients' median age was 6.0 years; 66% had an underlying diagnosis of leukemia. Independent predictors of IBD (n = 56) were absolute neutrophil count <100, temperature at presentation > or =39.0 degrees C, "sick" clinical appearance, and underlying diagnosis of acute myeloid leukemia. A total weighted score <24 reliably identified patients at low risk for IBD. Independent predictors of CC (n = 47) were relapse of malignancy, non-white race, "sick" clinical appearance, and underlying diagnosis of acute myeloid leukemia. A total weighted score <19 predicted patients at low risk for CC. Of those misclassified as low risk, 11 of 12 with IBD and 3 of 9 with CC had the outcome within 24 hours of presentation. Of the remaining patients classified as low-risk for IBD and CC, 99.5% and 97.1%, respectively, remained outcome-free after 24 hours of observation. CONCLUSIONS: This study identifies predictors of infection/complications in pediatric patients with FN, establishes clinical cut-off scores and highlights the importance of the initial clinical impression and 24 hours of observation. These prediction models warrant prospective validation.

Implementation of and barriers to routine HIV screening for adolescents.

OBJECTIVES: We developed and implemented a process for routine HIV screening, and we report screening practices and acceptance among adolescents at a large, urban, pediatric emergency department (ED). METHODS: We surveyed health care providers regarding their knowledge and beliefs about HIV and generated a protocol for routine HIV screening. Free, routine, opt-out, HIV screening was offered for all adolescents (13-18 years of age) presenting for care in the ED. We studied ED HIV screening rates, rates of test acceptance among patients/ guardians, patients' reasons for opting out, and HIV prevalence. A computerized prompt in the electronic chart was introduced 5 months after initiation, to address low screening rates. RESULTS: Of the 118 health care providers who responded to the preimplementation survey, 78% were unaware of the revised HIV testing guidelines and 58% predicted that routine screening would fail because of patient or guardian refusal. Of the 5399 patients who qualified for routine screening, 37% (2002) were offered opt-out screening. Of those, 13% opted out. Patients offered screening were more likely than patients not offered screening to be older (> or =15 years; P.002), female (P=.003), and nonwhite (P=.006). Older patients (> or =15 years of age) who were approached for screening were less likely to opt out (P=.002). Computerized prompting improved screening rates. One of the 1735 tests (0.57 per 1000 tests) performed yielded positive results for HIV. CONCLUSION: Adolescents and their guardians accept routine, optout, HIV screening, regardless of gender or race, and a computerized reminder enhances screening.

Pediatric invasive aspergillosis: a multicenter retrospective analysis of 139 contemporary cases.

OBJECTIVE: Invasive aspergillosis is a major cause of morbidity and mortality in immunocompromised children. Invasive aspergillosis has been well characterized in adults; however, the incidence and analysis of risk factors, diagnostic tools, treatments, and outcomes have not been well described for a large cohort of pediatric patients. METHODS: We conducted the largest retrospective review of contemporary cases of proven and probable pediatric invasive aspergillosis diagnosed at 6 major medical centers (January 1, 2000, to July 1, 2005). RESULTS: Aspergillus fumigatus was the species most frequently recovered (52.8%) for the 139 patients analyzed. The majority of the children had a malignancy with or without hematopoietic stem cell transplant. Significant risk factors that impacted survival were immunosuppressive therapies and allogeneic stem cell transplant. The most common clinical site of invasive aspergillosis was the lungs (59%), and the most frequent diagnostic radiologic finding was nodules (34.6%). Only 2.2% of children showed the air crescent sign, 11% demonstrated the halo sign, and cavitation was seen in 24.5% of patients. Before the diagnosis of invasive aspergillosis, 43.1% of patients received fluconazole, and 39.2% received liposomal amphotericin B. After the diagnosis of invasive aspergillosis, 57% were treated with a lipid formulation of amphotericin B; however, 45.8% received > or = 3 concomitant antifungal agents. Analysis did not show superiority of any 1 antifungal related to overall mortality. A total of 52.5% (73 of 139) died during treatment for invasive aspergillosis. Of all the interventions implemented, surgery was the only independent predictor of survival. CONCLUSIONS: Our analyses revealed common findings between adult and pediatric invasive aspergillosis. However, one key difference is diagnostic radiologic findings. Unlike adults, children frequently do not manifest cavitation or the air crescent or halo signs, and this can significantly impact diagnosis. Immune reconstitution, rather than specific antifungal therapy, was found to be the best predictor of survival.

Intracellular pharmacokinetics of once versus twice daily zidovudine and lamivudine in adolescents.

Zidovudine (ZDV) and lamivudine (3TC) metabolism to triphosphates (TP) is necessary for antiviral activity. The aims of this study were to compare ZDV-TP and 3TC-TP concentrations in adolescents receiving twice daily (BID) and once daily (QD) regimens and to determine the metabolite concentrations of ZDV and 3TC during chronic therapy on a QD regimen. Human immunodeficiency virus-infected patients (12 to 24 years) taking ZDV (600 mg/day) and 3TC (300 mg/day) as part of a highly active antiretroviral therapy regimen received QD and BID regimens of ZDV and 3TC for 7 to 14 days in a crossover design. Serial blood samples were obtained over 24 h on the QD regimen. Intracellular mono-, di-, and triphosphates for ZDV and 3TC were measured. The median ratio of BID/QD for ZDV-TP predose concentrations was 1.28 (95% confidence interval [CI] = 1.00 to 2.45) and for 3TC-TP was 1.12 (95% CI = 0.81 to 1.96). The typical population estimated half-lives (+/- the standard error of the mean) were 9.1 +/- 0.859 h for ZDV-TP and 17.7 +/- 2.8 h for 3TC-TP. Most patients had detectable levels of the TP of ZDV (24 of 27) and 3TC (24 of 25) 24 h after dosing, and half-lives on a QD regimen were similar to previously reported values when the drugs were given BID. Lower, but not significantly different, concentrations of ZDV-TP were demonstrated in the QD regimen compared to the BID regimen (P = 0.056). Although findings were similar between the BID and QD groups, the lower concentrations of ZDV and the number of patients below the level of detection after 24 h suggests that ZDV should continue to be administered BID.

SHP-1 inhibits LPS-mediated TNF and iNOS production in murine macrophages.

Several lines of evidence have suggested that protein tyrosine phosphatases, including CD45 and SHP-1, regulate macrophage activation. Macrophages from mice lacking SHP-1 (motheaten mice) are hyper-responsive to many stimuli, suggesting that SHP-1 may negatively regulate macrophage activation. Herein we report that the repressible/inducible over-expression of wild-type SHP-1 in a subclone of RAW 264.7 macrophages (RAW-TT10 cells) inhibited both TNF secretion and iNOS protein accumulation in response to stimulation with lipopolysaccharide (LPS) and recombinant murine interferon-gamma and led to diminished LPS-mediated tyrosine phosphorylation of vav1. In contrast, expression of a truncated SHP-1 construct previously shown to interfere with endogenous SHP-1 function modestly augmented LPS-mediated TNF and iNOS production and did not inhibit vav1 tyrosine phosphorylation. Taken together, these data provide the first direct evidence that SHP-1 inhibits macrophage activation by LPS and suggest that this effect may be mediated in part by dephosphorylation of vav1.

Early vancomycin therapy and adverse outcomes in children with pneumococcal meningitis.

BACKGROUND: Experts recommend that children with suspected pneumococcal meningitis should empirically receive combination therapy with vancomycin plus either ceftriaxone or cefotaxime. The relationship between timing of the first dose of vancomycin relative to other antibiotics and outcome in these children, however, has not been addressed. METHODS: Medical records of children with pneumococcal meningitis at a single institution from 1991-2001 were retrospectively reviewed. Vancomycin start time was defined as the number of hours from initiation of cefotaxime or ceftriaxone therapy until the administration of vancomycin therapy. Outcome variables were death, sensorineural hearing loss, and other neurologic deficits at discharge. Associations between independent variables and outcome variables were assessed in univariate and multiple logistic regression analyses. RESULTS: Of 114 subjects, 109 received empiric vancomycin therapy in combination with cefotaxime or ceftriaxone. Ten subjects (9%) died, whereas 37 (55%) of 67 survivors who underwent audiometry had documented hearing loss, and 14 (13%) of 104 survivors were discharged with other neurologic deficits. Subjects with hearing loss had a significantly shorter median vancomycin start time than did those with normal hearing (<1 vs 4 hours). Vancomycin start time was not significantly associated with death or other neurologic deficits in univariate or multivariate analyses. Multiple logistic regression revealed that hearing loss was independently associated with vancomycin start time <2 hours, blood leukocyte count <15000/microL, and cerebrospinal fluid glucose concentration <30 mg/dL. CONCLUSIONS: Early empiric vancomycin therapy was not clinically beneficial in children with pneumococcal meningitis but was associated with a substantially increased risk of hearing loss. It may be prudent to consider delaying the first dose of vancomycin therapy until > or =2 hours after the first dose of parenteral cephalosporin in children beginning therapy for suspected or confirmed pneumococcal meningitis.