Joint consensus statement on the vaccination of adult and paediatric haematopoietic stem cell transplant recipients: Prepared on behalf of the British society of blood and marrow transplantation and cellular therapy (BSBMTCT), the Children's cancer and Leukaemia Group (CCLG), and British Infection Association (BIA)

Haematopoietic stem cell transplant (HSCT) recipients have deficiencies in their adaptive immunity against vaccine preventable diseases. National and International guidance recommends that HSCT recipients are considered 'never vaccinated' and offered a comprehensive course of revaccination. This position statement aims to draw upon the current evidence base and existing guidelines, and align this with national vaccine availability and licensing considerations in order to recommend a pragmatic and standardised re-vaccination schedule for adult and paediatric HSCT recipients in the UK.

Thirteen-Valent Pneumococcal Conjugate Vaccine in Children With Acute Lymphoblastic Leukemia: Protective Immunity Can Be Achieved on Completion of Treatment

BACKGROUND

Children with acute lymphoblastic leukemia (ALL) are at increased risk of developing invasive pneumococcal disease. This study describes the immunogenicity of 13-valent pneumococcal conjugate vaccine (PCV13) during and after chemotherapy.

METHODS

Children with ALL were allocated to study groups and received a single dose of PCV13: group 1, maintenance chemotherapy; group 2, end of chemotherapy; group 3, 6 months after chemotherapy. A protective vaccine response was defined as at least 10 of 12 serotypes (or >83% of serotypes with data) achieving postvaccination serotype-specific immunoglobulin G ≥0.35 µg/mL and ≥4-fold rise, compared to prevaccination at 1 and 12 months.

RESULTS

One hundred eighteen children were recruited. Only 12.8% (5/39; 95% confidence interval [CI], 4.3%-27.4%) of patients vaccinated during maintenance (group 1) achieved a protective response at 1 month postvaccination and none had a protective response at 12 months. For group 2 patients, 59.5% (22/37; 95% CI, 42.1%-75.3%) achieved a response at 1 month and 37.9% (11/29; 95% CI, 20.7%-57.7%) maintained immunity at 12 months. For group 3 patients, 56.8% (21/37; 95% CI, 39.5%-72.9%) achieved a protective response at 1 month and 43.3% (13/30; 95% CI, 25.5%-62.6%) maintained immunity at 12 months.

CONCLUSIONS

This study demonstrated that the earliest time point at which protective immunity can be achieved in children with ALL is on completion of chemotherapy. This is earlier than current recommendations and may improve protection during a period when children are most susceptible to infection.

CLINICAL TRIALS REGISTRATION

EudraCT 2009-011587-11.

Immune reconstitution in children following chemotherapy for acute leukemia

Although survival rates for pediatric acute lymphoblastic leukemia are now excellent, this is at the expense of prolonged chemotherapy regimens. We report the long-term immune effects in children treated according to the UK Medical Research Council UKALL 2003 protocol. Peripheral blood lymphocyte subsets and immunoglobulin levels were studied in 116 participants, at six time points, during and for 18-month following treatment, with 30-39 patients analyzed at each time point. Total lymphocytes were reduced during maintenance chemotherapy and remained low 18 months following treatment completion. CD4 T cells remained significantly reduced 18 months after treatment, but CD8 cells and natural killer cells recovered to normal values. The fall in naïve B-cell numbers during maintenance was most marked, but numbers recovered rapidly after cessation of treatment. Memory B cells, particularly nonclass-switched memory B cells, remained below normal levels 18 months following treatment. All immunoglobulin subclasses were reduced during treatment compared to normal values, with IgM levels most affected. This study demonstrates that immune reconstitution differs between lymphocyte compartments. Although total B-cell numbers recover rapidly, disruption of memory/naïve balance persists and T-cell compartment persist at 18 months. This highlights the impact of modern chemotherapy regimens on immunity, and thus, infectious susceptibility and response to immunization.

1097 Sleep Disturbances, Sleep Burden, And Depressive Symptoms In US Hispanics/Latinos: Results From The HCHS/SOL Sueño Study

Introduction

While sleep disturbances and depression often co-occur, these associations are understudied among Hispanics/Latinos. We examined the associations of sleep disturbances and sleep burden with depressive symptoms among Hispanic/Latino adults in the United States.

Methods

We used cross-sectional data from the Hispanic Community Health Study/Study of Latinos Sueño Ancillary study (2010-2013). The study enrolled 2072 adults (ages 18-64; 51.5% females) who completed one-week wrist-actigraphy and sleep questionnaires. Sleep burden was operationalized as the total count of sleep disturbances across six domains (duration, efficiency, midpoint, variability, insomnia, sleepiness). Depressive symptoms were assessed using the Center for Epidemiological Studies Depression scale (CESD-10). We used weighted survey linear regressions to evaluate the association of sleep disturbances and sleep burden with elevated depressive symptoms (CESD≥10) in individual models adjusted for age, gender, site, heritage, nativity, education, income, and employment. Sensitivity analyses further adjusted for behavioral health risk factors and apnea-hypopnea index.

Results

An estimated 28.3% had elevated depressive symptoms, 8.0% had short sleep duration (<6 hours of sleep), 10.9% had long sleep duration (>9 hours), 45.2% exhibited a later sleep midpoint (≥4:00AM), 38.4% had high sleep timing variability (upper third tertile for between day sleep midpoint), 15.3% had insomnia (ISI≥10), 17.3% had excessive daytime sleepiness (ESS ≥10), 21.5% had poor sleep efficiency (<85%), and 77.4% had a total sleep burden count of ≥0. Insomnia (ß=0.49,95%CI:.43,.56), later sleep timing (ß=0.10,95%CI:.04,.16), excessive daytime sleepiness (ß=0.19,95%CI:.11,.27), poor sleep efficiency (ß=0.09,95%CI:.02,.17), high variability (ß=0.07, 95%CI:.01,.12), and sleep burden (ß=0.11,95%CI:.09,.13), were each positively associated with elevated depressive symptoms in individual adjusted models and sensitivity analyses. Extreme sleep durations were not associated with elevated depressive symptoms.

Conclusion

Multiple inter-related sleep disturbances, particularly those pertaining to sleep quality and timing, are associated with depression and may be targets for future interventions aimed at improving mood among Hispanics/Latinos.

Support

HL127307, HL098927, HL125748

0357 CPAP Adherence is Lower in Minority Neighborhoods

Introduction

The effectiveness of continuous positive airway pressure (CPAP) in treating obstructive sleep apnea (OSA) is limited by adherence. Small, single-center studies have reported CPAP adherence is lower in racial minorities suggesting disparities in OSA care. We used nationally representative data to assess racial differences in CPAP adherence at a neighborhood level.

Methods

Telemonitoring data were obtained from a therapy database maintained by a CPAP manufacturer. Usage over the first 90 days in patients initiated on CPAP between 11/01/2015 and 10/31/2018 who had at least one usage session, age 18-90 years, and valid U.S. zip code were mapped to a zip code tabulation area (ZCTA). Age- and sex-adjusted CPAP usage was calculated for each ZCTA with greater than 10 CPAP users. Ecologic analyses were performed to model the association of the proportion of blacks and Hispanics in each ZCTA (obtained from the 2013-2017 American Community Survey) on CPAP usage controlling for proportion of adults with bachelor’s degree and proportion of adults with household income below the poverty line.

Results

Our analysis included 13,118 ZCTAs averaging data over 737,274 patients. In adjusted analyses, each 10% increase in the proportion of blacks and Hispanics was associated with a 0.12 (95% CI 0.11-0.12) hour and 0.14 (95% CI 0.14-0.15) hour decrease in nightly CPAP use, respectively. Mean usage in ZCTAs with <1%, 1-2.5%, 2.5-10%, 10-25%, and 25-100% blacks were 4.96, 4.81, 4.67, 4.56, and 4.14 hours respectively (p<0.001). Mean usage in ZCTAs with <1%, 1-2.5%, 2.5-10%, 10-25%, and 25-100% Hispanics were 4.87, 4.86, 4.75, 4.50, and 4.10 hours respectively (p<0.001).

Conclusion

CPAP adherence is lower in neighborhoods with higher proportions of black and Hispanic residents independent of differences in education or poverty. These differences lead to lower likelihood of meeting insurance coverage requirements for CPAP therapy, potentially exacerbating sleep health disparities.

Support

Philips Respironics, NIH R25HL130600 and K24HL127307.

0402 Impact of Various Actigraphic Editing Approaches on Sleep/Wake Outputs in Adults with Insomnia and Healthy Sleepers

Introduction

Actigraphy data can be edited using a variety of approaches. However, whether time-intensive manual editing provides different sleep/wake estimates compared to other approaches is unknown. The purpose of this study was to compare sleep/wake data obtained from a standardized editing approach that incorporates multiple inputs versus three other common approaches.

Methods

72 adults (33.8±11.1 y, 74% female, 71% white) provided 1022 nights of data for analysis; 45 were healthy sleepers (678 nights) and 27 met DSM-5 criteria for insomnia. Participants wore an Actiwatch Spectrum on their nondominant wrist and completed a sleep diary for 3-24 nights. Each night’s rest interval was set using four different approaches: (1) a standardized process based upon published guidelines (Patel et al., Sleep 2015) that incorporates a hierarchical order of multiple inputs (event marker, light, diary, activity; STANDARD); (2) software-provided automated algorithm (AUTO); (3) automated algorithm with incorporation of event markers (AUTOE); and (4) sleep diary (DIARY). We used linear mixed-effects models to evaluate whether sleep/wake parameters differed between the STANDARD and other editing approaches, accounting for patient status (healthy sleeper, insomnia) and the possibility that differences among editing approaches may be dependent on patient status.

Results

All results are expressed relative to the STANDARD approach. Bedtime was 36.1±5.1 min earlier (P<.0001) and morning out-of-bed time was 13.6±5.7 min later (P=.02) using the AUTO (P<.0001) approach. Time in bed was 42.3±4.7 min longer with AUTO (P<.0001). Sleep onset latency was 11.7±1.4 min and 2.8±1.4 min longer for AUTO (P<.0001) and DIARY (P=.05), respectively. Sleep duration was 22.5±4.4 min longer with AUTO (P<.0001). Wake after sleep onset was 6.8±1.2 min greater with AUTO (P<.0001). Similar patterns were observed for all sleep/wake measures among healthy sleepers and adults with insomnia.

Conclusion

A standardized approach to editing actigraphy data leads to different sleep/wake estimates compared to other common approaches, though the differences were often small in magnitude and not dependent upon sleep status. Most notably, reliance upon the automated algorithm yielded longer time in bed, sleep duration, sleep onset latency, and wake after sleep onset compared to the standardized approach.

Support

NIH K23HL118318

0677 Patient Preferences On Initiating Treatment With Continuous Positive Airway Pressure

Introduction

Clinical guidelines recommend continuous positive airway pressure (CPAP) therapy be initiated in patients with obstructive sleep apnea (OSA) either at home using an auto-titrating device or following manual titration in the sleep laboratory. Patient preference between these two options is unknown.

Methods

Patients newly prescribed CPAP therapy for the treatment of OSA at an academic sleep medicine clinic were surveyed by telephone within one month of initiating treatment. Data on demographics, disease severity and CPAP adherence were obtained from the medical record.

Results

A total of 75 participants (56% male, mean age 52±15 yrs, 48% moderate to severe OSA) were surveyed. Physicians prescribed home initiation of CPAP in 51%, lab initiation in 23%, and allowed the patient to choose in 27% of cases. Overall, 67% of participants (95% CI [56%-77%]) reported preference for home initiation. Preference for home initiation did not vary by age, sex, AHI, degree of sleepiness, or type of diagnostic study (home vs. lab sleep study) performed (p>0.10 for all). Convenience (44%) and starting treatment faster (44%) were the most common reasons provided for those favoring home initiation, while sleep technician availability (40%), optimization of pressure settings (32%), and ability to try multiple masks (28%) were cited by those favoring lab initiation. The prevalence of CPAP adherence at 90 days tended to be higher in those whose treatment was initiated aligned to preference (79% in those whose treatment initiation was concordant with preference vs. 64% in those whose treatment initiation was discordant, p=0.16).

Conclusion

Overall, two-thirds of patients with OSA prefer initiation of CPAP be done at home. This preference does not vary by demographics, OSA severity or diagnostic modality. Initiating treatment concordant with patient preference may lead to greater adherence.

Support

American Thoracic Society Academic Sleep Pulmonary Integrated Research/Clinical (ASPIRE) Fellowship, K24 HL127307

1144 Actigraphy-defined Sleep And Neurocognitive Decline In Middle-age Hispanic/Latino Adults

Introduction

Few studies have evaluated objective sleep measures and longitudinal neurocognitive decline, particularly in middle-age or Hispanic/Latino adults. We evaluated prospective associations between actigraphy-defined sleep and 7-year neurocognitive change among Hispanic/Latino adults. We hypothesized that sleep duration would be associated with neurocognitive decline.

Methods

We analyzed data from 1,036 adults 45-64 years of age from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a multi-center prospective cohort study of diverse community-dwelling Hispanic/Latino adults. At Visit 1 (2008-2011), participants underwent neurocognitive assessments, 7-days of actigraphy, home sleep testing, and sleep questionnaires (including the Insomnia Severity Index). Seven years later, participants repeated neurocognitive assessments. The neurocognitive battery included the Six-Item Screener, Brief Spanish-English Verbal Learning Test, phonemic word fluency test, and Digit Symbol Subtest. Survey linear regression was used to evaluate prospective associations between actigraphy-defined or self-reported sleep variables and neurocognitive change. Final models adjusted for objectively-defined variables (age, body-mass index, Field Center, and time between neurocognitive assessments), and self-reported variables (sex, education, Hispanic/Latino background, alcohol consumption, physical activity, heart failure, cerebrovascular events, depression and anxiety symptoms, and antidepressant use).

Results

At Visit 1, the sample was 55% female and mean age was 54.9±2.2 years. The mean sleep duration was 402.6±27.6 minutes, mean sleep-onset latency was 11.3±9.7 minutes, mean number of days with naps of ≥ 15 minutes duration was 1.1±0.7, and mean sleep-time per nap was 51±14.1 minutes. Increased sleep-onset latency was associated with 7-year declines in global neurocognitive function (β=-0.0026, p<0.01), verbal learning (β=-0.0028, p<0.001) and verbal memory (β=-0.036, p<0.05). Increased sleep-time per nap predicted better verbal memory (β=0.0038, p<0.05). In contrast, sleep duration, sleep fragmentation, and self-reported sleep measures were not associated with neurocognitive change.

Conclusion

Among middle-age adults, sleep-onset latency and nap duration were associated with neurocognitive change. These findings may serve as targets for intervention of neurocognitive decline.

Support

This work is supported by the National Institute on Aging: R01AG048642, RF1AG054548, R01AG061022, R21AG056952, and R21HL140437 (AR).

0609 Sleep Phenotypes in Middle-Aged and Older Hispanics/Latinos. Results from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

Introduction

Identifying sleep phenotypes in the diverse and understudied US Hispanic/Latino population is critical to developing interventions and mitigating distal clinical outcomes (e.g. dementias).

Methods

Using latent class analyses (LCA), we identify empirically derived and clinically meaningful sleep phenotypes using data on community dwelling middle-aged/older adults (ages ≥45-years) from the HCHS/SOL (2008-2011) - Investigation of Neurocognitive Aging (n=6,377). Sleep variables used included Apnea/Hypopnea Index (AHI), percent time SpO2<90%, Epworth Sleepiness Scale (ESS), Women’s Health Initiative Insomnia Rating Scale (WHIIRS), self-reported average sleep duration, restless legs symptoms, napping frequency, and sleep quality.

Results

Mean (M) age was 56.4±8.1 years, and 54.7% were female. Average AHI, ESS, WHIIRS, and sleep duration were 8.7±13.1, 6.0±5.0, 7.6±5.5, and 7.8±1.4, respectively, and 25.8% had zero percent time SpO2 <90%. Fit statistics indicated that a four-class solution provided the best data fit. The derived classes, adjusting for age, sex, income, and acculturation, corresponded with four clinically meaningful groups: (1) 28.8% were asymptomatic [(M) AHI=0.8; (M) ESS=5.6; (M)WHIIRS=7.6; (M) sleep duration=7.8; 0% SpO2<90%=74.1%], (2) 25.7 % were asymptomatic mild sleep apnea [(M) AHI=6.2; (M) ESS=3.8; (M) WHIIRS=2.9; (M) sleep duration=7.8; 0% SpO2<90%=8.8%], (3) 19.4% were symptomatic sleep apnea [(M) AHI=25.6; (M) ESS=8.5; (M) WHIIRS=7.2; (M) sleep duration=7.7; 0% SpO2<90%= 0.5%], and (4) 26.1% were insomnia [(M) AHI=5.7; (M) ESS=6.7; (M) WHIIRS=13.0; (M) sleep duration=7.8; 0% SpO2<90%=10.3%]. Classification into groups 3 and 4 were primarily driven by elevated AHI and WHIIRS scores, respectively. The distribution of scores in the derived groups suggest variations relative to current clinical thresholds.

Conclusion

We identified 4-groups using LCA in a community-based sample of diverse U.S. Hispanic/Latino adults. Better characterization of sleep phenotypes for Hispanics/Latinos can help in developing targeted interventions studies and ameliorate health disparities.

Support

5R01AG048642-05; R21AG056952; R21HL140437.

0607 Clinical Phenotypes of OSA in Diverse Hispanics/Latinos: Results from the Hispanic Community Health Study/Study of Latinos

Introduction

Recent work on US non-Latino Whites and Europeans from clinical samples used obstructive sleep apnea (OSA) symptoms to generate OSA phenotypes for individuals with moderate-severe OSA and proposed between 3-5 clusters. Validating these clusters in a diverse Hispanic/Latino community-based population with different biopsychosocial characteristics is crucial for early OSA identification and more personalized treatment.

Methods

This work is based on baseline data from The Hispanic Community Health Study/Study of Latinos (HCHS/SOL). HCHS/SOL is a prospective cohort study designed using a multisite (Bronx, NY, Chicago, IL, Miami, FL, San Diego, CA) multistage probability sample. The subpopulation of interest included adults 18-74 years (unweighted n=1,623) meeting criteria for moderate-severe OSA symptoms (≥15 Apnea-Hypopnea index (AHI) events per hour). We performed latent class analysis (LCA) using 15 common OSA symptoms to identify phenotype clusters.

Results

Average age was 52.4 ± 13.9 years and 34.1% were female. Mean AHI was 33.8 ± 22.5 events per hour. Fit statistics and clinical significance suggested that a three-class solution provided best fit to the data. The symptom profiles were consistent with (1) a Minimally Symptomatic group (46.8%), (2) a Disturbed Sleep group (38.1%), and (3) a Daytime Sleepiness group (15.1%). Validation analyses using alternative hierarchical and partitioning algorithms also suggested support for a three-class solution.

Conclusion

Sleep apnea phenotypes among diverse Hispanics/Latinos were consistent with recent findings from the Sleep Apnea Global Interdisciplinary Consortium. However, we found notable differences in the prevalence of these clusters relative to Whites. This suggests that other biopsychosocial factors may be contributing to OSA phenotypes among Hispanics/Latinos. Identification of OSA phenotypes in Hispanics/Latinos could inform better sleep interventions and therapeutics and help better align public health resources.

Support

5R01AG048642-05; R21AG056952; R21HL140437.

Mid-cervical interneuron networks following high cervical spinal cord injury

Spinal interneuron (IN) networks can facilitate respiratory motor recovery after spinal cord injury (SCI). We hypothesized that excitatory synaptic connectivity between INs located immediately caudal to unilateral cervical SCI would be most prevalent in a contra- to ipsilateral direction. Adult rats were studied following chronic C2 spinal cord hemisection (C2Hx) injury. Rats were anesthetized and ventilated and a multi-electrode array was used to simultaneously record INs on both sides of the C4-5 spinal cord. The temporal firing relationship between IN pairs was evaluated using cross-correlation with directionality of synaptic connections inferred based on electrode location. During baseline recordings, the majority of detectable excitatory IN connections occurred in a contra- to- ipsilateral direction. However, acute respiratory stimulation with hypoxia abolished this directionality, while simultaneously increasing the detectable inhibitory connections within the ipsilateral cord. We conclude that propriospinal networks caudal to SCI can display a contralateral-to-ipsilateral directionality of synaptic connections and that these connections are modulated by acute exposure to hypoxia.

PEPtalk2: results of a pilot randomised controlled trial to compare VZIG and aciclovir as postexposure prophylaxis (PEP) against chickenpox in children with cancer

OBJECTIVE

To determine the likely rate of patient randomisation and to facilitate sample size calculation for a full-scale phase III trial of varicella zoster immunoglobulin (VZIG) and aciclovir as postexposure prophylaxis against chickenpox in children with cancer.

DESIGN

Multicentre pilot randomised controlled trial of VZIG and oral aciclovir.

SETTING

England, UK.

PATIENTS

Children under 16 years of age with a diagnosis of cancer: currently or within 6 months of receiving cancer treatment and with negative varicella zoster virus (VZV) serostatus at diagnosis or within the last 3 months.

INTERVENTIONS

Study participants who have a significant VZV exposure were randomised to receive PEP in the form of VZIG or aciclovir after the exposure.

MAIN OUTCOME MEASURES

Number of patients registered and randomised within 12 months of the trial opening to recruitment and incidence of breakthrough varicella.

RESULTS

The study opened in six sites over a 13-month period. 482 patients were screened for eligibility, 32 patients were registered and 3 patients were randomised following VZV exposure. All three were randomised to receive aciclovir and there were no cases of breakthrough varicella.

CONCLUSIONS

Given the limited recruitment to the PEPtalk2 pilot, it is unlikely that the necessary sample size would be achievable using this strategy in a full-scale trial. The study identified factors that could be used to modify the design of a definitive trial but other options for defining the best means to protect such children against VZV should be explored.

TRIAL REGISTRATION NUMBER

ISRCTN48257441, EudraCT number: 2013-001332-22, sponsor: University of Birmingham.

Coupling multielectrode array recordings with silver labeling of recording sites to study cervical spinal network connectivity

Midcervical spinal interneurons form a complex and diffuse network and may be involved in modulating phrenic motor output. The intent of the current work was to enable a better understanding of midcervical "network-level" connectivity by pairing the neurophysiological multielectrode array (MEA) data with histological verification of the recording locations. We first developed a method to deliver 100-nA currents to electroplate silver onto and subsequently deposit silver from electrode tips after obtaining midcervical (C3-C5) recordings using an MEA in anesthetized and ventilated adult rats. Spinal tissue was then fixed, harvested, and histologically processed to "develop" the deposited silver. Histological studies verified that the silver deposition method discretely labeled (50-μm resolution) spinal recording locations between laminae IV and X in cervical segments C3-C5. Using correlative techniques, we next tested the hypothesis that midcervical neuronal discharge patterns are temporally linked. Cross-correlation histograms produced few positive peaks (5.3%) in the range of 0-0.4 ms, but 21.4% of neuronal pairs had correlogram peaks with a lag of ≥0.6 ms. These results are consistent with synchronous discharge involving mono- and polysynaptic connections among midcervical neurons. We conclude that there is a high degree of synaptic connectivity in the midcervical spinal cord and that the silver-labeling method can reliably mark metal electrode recording sites and "map" interneuron populations, thereby providing a low-cost and effective tool for use in MEA experiments. We suggest that this method will be useful for further exploration of midcervical network connectivity.NEW & NOTEWORTHY We describe a method that reliably identifies the locations of multielectrode array (MEA) recording sites while preserving the surrounding tissue for immunohistochemistry. To our knowledge, this is the first cost-effective method to identify the anatomic locations of neuronal ensembles recorded with a MEA during acute preparations without the requirement of specialized array electrodes. In addition, evaluation of activity recorded from silver-labeled sites revealed a previously unappreciated degree of connectivity between midcervical interneurons.

Varicella zoster immune status in children treated for acute leukemia

Children treated for acute leukemia are at increased risk of severe infection with varicella zoster virus (VZV). We studied the VZV sero-status of children with acute leukemia prior to starting chemotherapy and after completion of chemotherapy. VZV sero-status was assessed using time resolved fluorescence immunoassay (TRFIA) before starting treatment and 6 months after completion of treatment. Prior to starting treatment for acute leukemia, a significant proportion of children (35%) are VZV seronegative. On completion of treatment most patients maintained protective VZV antibody levels; however, 35% had reduced/loss VZV antibody to a level considered non-protective and susceptible to VZV infection.

The effect of hypercapnia on the sensitivity to flicker defined stimuli

BACKGROUND/AIMS

To investigate the effect of increased CO2 levels on flicker defined stimuli.

METHODS

The sensitivity of two flicker defined tasks was measured in nine healthy, trained observers using the Flicker Defined Form (FDF) stimulus of the Heidelberg Edge Perimeter (HEP; Heidelberg Engineering) and Frequency Doubling Technology (FDT) stimulus of the Matrix perimeter (Carl Zeiss Meditec) during normoxia and 15% hypercapnia (end-tidal CO2 increased by 15% relative to baseline). HEP-FDF and Matrix-FDT sensitivities were analysed for the global field, superior and inferior hemifields and at specific matched eccentricities, using repeated measures analysis of variance. The main effect of hypercapnia on flicker sensitivity was analysed using regression models.

RESULTS

Higher flicker sensitivity outcomes with increasing CO2 values were found for HEP-FDF and Matrix-FDT with a statistically significant main effect for HEP-FDF global, superior and inferior hemifields (p<0.01 for all) as well as 6°, 18°, 12° and 24° eccentricities (p=0.03, 0.04, 0.01, 0.05, respectively). When comparing mean sensitivity values between normocapnia and hypercapnia conditions, no statistically significantly different results were found for HEP-FDF and Matrix-FDT (p>0.05).

CONCLUSIONS

As CO2 levels were increased in healthy young individuals, there was an associated increase in visual sensitivity that was only significant for HEP-FDF stimuli, highlighting the different mechanisms involved in processing each of HEP-FDF and Matrix-FDT stimuli. Mean visual sensitivity outcomes were found to be similar for normocapnia and hypercapnia suggesting that a capability to compensate for a mild and stable increase in systemic CO2 levels may exist.

Helicobacter pylori downregulates expression of human β-defensin 1 in the gastric mucosa in a type IV secretion-dependent fashion

Helicobacter pylori establishes a chronic lifelong infection in the human gastric mucosa, which may lead to peptic ulcer disease or gastric adenocarcinoma. The human beta-defensins (hβDs) are antimicrobial peptides, hβD1 being constitutively expressed in the human stomach. We hypothesized that H. pylori may persist, in part, by downregulating gastric hβD1 expression. We measured hβD1 and hβD2 expression in vivo in relation to the presence, density and severity of H. pylori infection, investigated differential effects of H. pylori virulence factors, and studied underlying signalling mechanisms in vitro. Significantly lower hβD1 and higher hβD2 mRNA and protein concentrations were present in gastric biopsies from infected patients. Those patients with higher-level bacterial colonization and inflammation had significantly lower hβD1 expression, but there were no differences in hβD2. H. pylori infection of human gastric epithelial cell lines also downregulated hβD1. Using wild-type strains and isogenic mutants, we showed that a functionalcag pathogenicity island-encoded type IV secretion system induced this downregulation. Treatment with chemical inhibitors or siRNA revealed that H. pylori usurped NF-κB signalling to modulate hβD1 expression. These data indicate that H. pylori downregulates hβD1 expression via NF-κB signalling, and suggest that this may promote bacterial survival and persistence in the gastric niche.

Comparative efficacy of two standard methods for determination of iron and zinc in fruits, pulses and cereals

Micronutrients are essential elements needed in small amounts for adequate human nutrition and include the elements iron and zinc. Both of these minerals are essential to human well-being and an adequate supply of iron and zinc help to prevent iron deficiency anaemia and zinc deficiency, two prevalent health concerns of the developing world. The levels of zinc and, iron were measured in the Banana, Papaya, Rice, Finger millet, Soybean and Urdbean. Standard Atomic absorption spectroscopy (AAS) method was also applied to all the samples for zinc and iron analysis and compared with inductively coupled plasma mass spectroscopy (ICP-MS). It was observed that there was no matrix interference affecting the determination of both elements interested in all the samples analyzed. Average concentration relative standard deviation and standard deviation were used for the statistical evaluation of the results for both elements. Correlation coefficient was used as statistical model to compare both the techniques.

Serotype-specific pneumococcal antibody concentrations in children treated for acute leukaemia

Children treated for acute leukaemia are at increased risk of infection with Streptococcus pneumoniae. The basis for this may include low levels of pneumococcal antibody but this has not been well studied. The authors measured serotype-specific pneumococcal IgG antibody concentrations in children treated for acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML) ≥6 months after completion of standard-dose chemotherapy. Pneumococcal serotype-specific IgG antibody concentrations were low. None of the subjects had protective concentrations against all the heptavalent-pneumococcal conjugate vaccine serotypes. There was no significant difference in antibody concentrations between subjects with ALL and AML (p≥0.05). Children treated for ALL and AML generally have non-protective antibody concentrations against S pneumoniae. There is significant morbidity associated with pneumococcal disease in this patient group and strategies for vaccination are required.

Phase II Study of Paclitaxel in Patients With Soft Tissue Sarcomas

Purpose. Patients with soft tissue sarcoma (STS) who have previously received standard chemotherapy including adriamycin (doxorubicin), ifosfamide, cyclophosphamide and DTIC (dacarbazine) have very limited therapeutic options. It is important to identify new drugs with some activity in this disease and we therefore undertook this trial to determine the antitumor activity of paclitaxel (Taxol).Methods. We conducted a phase II study of paclitaxel in patients with STS who had received prior standard chemotherapy. Paclitaxel was administered at a starting dose of 200 mg m(-2) as a 24-h infusion with STS premedication, every 21 days or upon hematologic recovery (absolute granulocyte count (AGC) >/= 1500/mul, platelets >/= 100 000/mul). Neupogen was not used routinely. The study was conducted based on a two-stage design proposed by Simon. Responses were assessed radiographically using standard criteria.Results. Nineteen eligible patients were treated in the first stage of the study. The median age was 50 years (range 20-68 years), and there were nine females and 10 males with Zubrod performance status of 1 or 2. One patient achieved a minor response. Median AGC nadir was 0.1/mul on day 12 with absolute neutropenia lasting 5 days. Median platelet nadir was 171 000/mul on day 9. There were no grade 3/4 non-hematologic toxicities and no deaths related to treatment.Discussion. Paclitaxel, at this dose and schedule, is well tolerated but inactive in this patient population.

Identification of patient safety improvement targets in successful vascular and endovascular procedures: analysis of 251 hours of complex arterial surgery

OBJECTIVES

To investigate failures in patient safety for patients undergoing vascular and endovascular procedures to guide future quality and safety interventions.

DESIGN

Single centre prospective observational study.

METHODS

66 procedures (17 thoracoabdominal and 23 abdominal aortic aneurysms, 4 carotid and 22 limb procedures) were observed prospectively over a 9-month period (251 h operating time) by two trained observers. Event logs were recorded for each procedure. Two blinded experts identified and independently categorised failures into 22 types (using a validated category tool) and severity (5-point scale). Data are expressed as median (range). Statistical analysis was performed using Mann-Whitney U, Kruskal-Wallis and Spearman's Rank tests.

RESULTS

1145 failures were identified with good inter-assessor reliability (Cronbach's alpha 0.844). The commonest failure types related to equipment (including unavailability, configuration and other failures) (269/1145 [23.5%]) and communication (240/1145 [21.0%]). A comparatively lower number of technical and psychomotor failures were identified (103 [9.0%]). The number of failures correlated with procedure duration (rho = 0.695, p < 0.001) but not anatomical site of the procedure or pathology of the disease process. Failure rate was higher in patients undergoing combined surgical/endovascular procedures compared to open surgery (median 5.7/h [IQR 4.2-8.1] vs 3.0/h [2.5-3.5]; p < 0.001). The severity of failures was similar (1.5/5 [1-2] vs 1/5 [1-2] respectively; p = 0.095). For combined procedures, failure rates were significantly higher during the endovascular phase (9.6/h [7.5-13.7]) compared to the non-endovascular phase (3.0/h [1.0-5.0]; p < 0.001).

CONCLUSIONS

Failures in patient safety are common during complex arterial procedures. Few failures were severe, although minor failures during critical stages and accumulation of multiple minor failures may potentially be important. Failures occurred especially during the endovascular phase and were often related to equipment or communication aspects. Interventions to improve procedural safety and quality of care should primarily target these specific areas.

Hereditary leiomyomatosis and renal cell carcinoma: very early diagnosis of renal cancer in a paediatric patient

Hereditary leiomyomatosis and renal cell cancer is a hereditary cancer syndrome in which affected individuals are at risk for cutaneous and uterine leiomyomas, and renal cancer. Previous reports have stressed the aggressiveness of the renal tumours, often with early metastasis, despite small primary tumour size. Almost all the previously reported patients were adults, and different studies showed variability in penetrance for the renal tumours. We report a patient in whom renal cancer was detected at the age of 11 years at his first routine screening imaging after he was found to carry a fumarate hydratase gene mutation (c.1189G > A) transmitted from his mother. This report serves to emphasize the need to improve guidelines for screening of at risk individuals, including the necessity for predictive genetic testing and early institution of tumour surveillance in childhood.

Providing skilled birth attendants and emergency obstetric care to the poor through partnership with private sector obstetricians in Gujarat, India

PROBLEM

India has the world's largest number of maternal deaths estimated at 117,000 per year. Past efforts to provide skilled birth attendants and emergency obstetric care in rural areas have not succeeded because obstetricians are not willing to be posted in government hospitals at subdistrict level.

APPROACH

We have documented an innovative public-private partnership scheme between the Government of Gujarat, in India, and private obstetricians practising in rural areas to provide delivery care to poor women.

LOCAL SETTING

In April 2007, the majority of poor women delivered their babies at home without skilled care.

RELEVANT CHANGES

More than 800 obstetricians joined the scheme and more than 176,000 poor women delivered in private facilities. We estimate that the coverage of deliveries among poor women under the scheme increased from 27% to 53% between April and October 2007. The programme is considered very successful and shows that these types of social health insurance programmes can be managed by the state health department without help from any insurance company or international donor.

LESSONS LEARNED

At least in some areas of India, it is possible to develop large-scale partnerships with the private sector to provide skilled birth attendants and emergency obstetric care to poor women at a relatively small cost. Poor women will take up the benefit of skilled delivery care rapidly, if they do not have to pay for it.

Immunisation practices of paediatric oncology and shared care oncology consultants: a United Kingdom survey

BACKGROUND

In March 2002, the Royal College of Paediatrics and Child Health (RCPCH) introduced guidelines for re-immunisation of children after completion of standard-dose chemotherapy and after haematopoietic stem cell transplant (HSCT).

AIMS

To ascertain whether these guidelines form standard unit policy by undertaking a survey of UK paediatric principal treatment centre (PTC) consultants and shared care (SC) consultants.

PROCEDURES

In October 2008, a link to an on-line anonymised survey was sent by e-mail to all UK PTC consultants in Children's Cancer and Leukaemia Group (CCLG) centres and to SC consultants linked to eight of these centres.

RESULTS

Responses were received from 55 PTC consultants (representing all 21 CCLG centres) and 54 SC consultants. In accordance with the RCPCH guidelines, most PTC and SC consultants recommend initiating re-immunisation at 6 months after completion of standard-dose chemotherapy (99/105, 94.3%). Re-immunisation at the recommended time after HSCT for each transplant type was reported by 93-100% of respondents. Pneumococcal conjugate vaccine (PCV) was recommended after chemotherapy by 58.3% (35/60) of respondents and by 51.7% (30/58) after HSCT. There were distinct differences between PTC and SC consultants in their choice of varicella (VZV) post-exposure prophylaxis.

CONCLUSIONS

There is a high level of stated compliance with RCPCH guidelines. Recommendations for PCV after chemotherapy and HSCT were lower than expected. This may reflect the absence of specific guidelines after chemotherapy but not in HSCT patients where guidelines do exist. Variation in VZV post-exposure prophylaxis suggests further studies are required.

A polymorphism in the VKORC1 regulator calumenin predicts higher warfarin dose requirements in African Americans

Warfarin demonstrates a wide interindividual variability in response that is mediated partly by variants in cytochrome P450 2C9 (CYP2C9) and vitamin K 2,3-epoxide reductase complex subunit 1 (VKORC1). It is not known whether variants in calumenin (CALU) (vitamin K reductase regulator) have an influence on warfarin dose requirements. We resequenced CALU regions in a discovery cohort of dose outliers: patients with high (>90th percentile, n = 55) or low (<10th percentile, n = 53) warfarin dose requirements (after accounting for known genetic and nongenetic variables). One CALU variant, rs339097, was associated with high doses (P = 0.01). We validated this variant as a predictor of higher warfarin doses in two replication cohorts: (i) 496 patients of mixed ethnicity and (ii) 194 African-American patients. The G allele of rs339097 (the allele frequency was 0.14 in African Americans and 0.002 in Caucasians) was associated with the requirement for a 14.5% (SD +/- 7%) higher therapeutic dose (P = 0.03) in the first replication cohort and a higher-than-predicted dose in the second replication cohort (allele frequency 0.14, one-sided P = 0.03). CALU rs339097 A>G is associated with higher warfarin dose requirements, independent of known genetic and nongenetic predictors of warfarin dose in African Americans.

Genetic and clinical predictors of warfarin dose requirements in African Americans

The objective of this study was to determine whether, in African-American patients, additional vitamin K oxidoreductase complex subunit 1 (VKORC1), cytochrome P450 2C9 (CYP2C9), CYP4F2, or apolipoprotein E (APOE) polymorphisms contribute to variability in the warfarin maintenance dose beyond what is attributable to the CYP2C9*2 and *3 alleles and the VKORC1 -1639G>A genotype. In a cohort of 226 African-American patients, weekly warfarin dose requirements were lower in those with the CYP2C9*8 allele (34 (30-47) mg; P = 0.023) and the CYP2C9 *2, *3, *5, *6, or *11 allele (33(28-40 mg); P < 0.001) as compared with those with the CYP2C9*1/*1 genotype (43 (35-56) mg). The combination of CYP2C9 alleles, VKORC1 -1639G>A genotype, and clinical variables explained 36% of the interpatient variability in warfarin dose requirements. By comparison, a model without the CYP2C9*5, *6, *8, and *11 alleles explained 30% of the variability in dose. No other VKORC1, CYP4F2, or APOE polymorphism contributed to the variance. The inclusion of additional CYP2C9 variants may improve the predictive ability of warfarin dosing algorithms for African Americans.

Reduced sleep as an obesity risk factor

Poor sleep has increasingly gained attention as a potential contributor to the recent obesity epidemic. The increased prevalence of obesity in Western nations over the past half-century has been paralleled by a severe reduction in sleep duration. Physiological studies suggest reduced sleep may impact hormonal regulation of appetite. Prospective studies suggest reduced habitual sleep duration as assessed by self-report is an independent risk factor for an increased rate of weight gain and incident obesity. Cross-sectional studies have demonstrated that the association between reduced sleep and obesity persists when sleep habits are measured objectively, that the association is as a result of elevations in fat and not muscle mass and that this association is not related to sleep apnoea. Thus, reduced sleep appears to represent a novel, independent risk factor for increased weight gain. Further research is needed to determine whether interventions aimed at increasing sleep may be useful in combating obesity.

Using linkage analysis to identify quantitative trait loci for sleep apnea in relationship to body mass index

To understand the genetics of sleep apnea, we evaluated the relationship between the apnea hypopnea index (AHI) and body mass index (BMI) through linkage analysis to identify genetic loci that may influence AHI and BMI jointly and AHI independent of BMI. Haseman-Elston sibling regression was conducted on AHI, AHI adjusted for BMI and BMI in African-American and European-American pedigrees. A comparison of the magnitude of linkage peaks was used to assess the relationship between AHI and BMI. In EAs, the strongest evidence for linkage to AHI was on 6q23-25 and 10q24-q25, both decreasing after BMI adjustment, suggesting loci with pleiotropic effects. Also, a promising area of linkage to AHI but not BMI was observed on 6p11-q11 near the orexin-2 receptor, suggesting BMI independent pathways. In AAs the strongest evidence of linkage for AHI after adjusting for BMI was on chromosome 8p21.3 with linkage increasing after BMI adjustment and on 8q24.1 with linkage decreasing after BMI adjustment. Novel linkage peaks were also observed in AAs to both BMI and AHI on chromosome 13 near the serotonin-2a receptor. These analyses suggest genetic loci for sleep apnea that operate both independently of BMI and through BMI-related pathways.

Heritability of upper airway dimensions derived using acoustic pharyngometry

Acoustic pharyngometry represents a simple, quick noninvasive method of measuring upper airway dimensions, which are predictive of sleep apnoea risk. The aim of the present study was to assess the genetic basis of upper airway size as determined using pharyngometry. Participants in the Cleveland Family Study aged >14 yrs underwent three acoustic pharyngometric measurements. Variance component models adjusted for age and sex were used to estimate the heritability of pharyngometry-derived airway measures. A total of 568 out of 655 (87%) subjects provided pharyngometric curves of sufficient quality. Although African-Americans tended to show narrower airways compared with white subjects, heritability patterns were similar in these two groups. The minimum cross-sectional area exhibited a heritability of 0.34 in white subjects and 0.39 in African-Americans, suggesting that 30-40% of the total variance in this measure is explained by shared familial factors. Estimates were unchanged after adjustment for body mass index or neck circumference. In contrast, oropharyngeal length did not show significant heritability in either ethnic group. The minimum cross-sectional area of the oropharynx is a highly heritable trait, suggesting the presence of an underlying genetic basis. These findings demonstrate the potential utility of acoustic pharyngometry in dissecting the genetic basis of sleep apnoea.

Revaccination of Children after Completion of Standard Chemotherapy for Acute Leukemia

BACKGROUND

After the treatment of patients with acute leukemia, there is a decrease in vaccine-specific antibody and an increased susceptibility to certain vaccine-preventable diseases. A simple revaccination schedule is warranted.

METHOD

Fifty-nine children (age, 1-18 years) who had completed standard chemotherapy in accordance with Medical Research Council of United Kingdom protocols were recruited. All children received a single dose of Haemophilus influenzae type b (Hib), tetanus, diphtheria, acellular pertussis, meningococcus C, polio, measles, mumps, and rubella vaccines > or = 6 months after completion of treatment. Antibody concentrations were measured before vaccination and 2-4 weeks and 12 months after vaccination.

RESULTS

Prevaccination antibody levels were protective for all patients for tetanus (geometric mean concentration [GMC], 0.13 IU/mL; 95% CI, 0.1-0.17 IU/mL), for 87% for Hib (GMC, 0.5 microg/mL; 95% CI, 0.37-0.74 microg/mL), for 71% for measles (GMC, 301 mIU/mL; 95% CI, 163-557 mIU/mL), for 12% for meningococcus C (geometric mean titer [GMT], 1:2.9; 95% CI, 1:2.2 to 1:3.9), and for 11% for all 3 poliovirus serotypes. Revaccination resulted in a significant increase in levels of antibody to each vaccine antigen, with 100% of patients achieving optimal antitetanus antibody concentrations (defined as > 0.1 IU/mL; 1.5 IU/mL; 95% CI, 1.1-2.1 IU/mL), 93% achieving optimal antibody concentrations to Hib (defined as > 1.0 microg/mL; 6.5 microg/mL; 95% CI, 5.1-8.2 microg/mL), 94% achieving optimal antibody concentrations to measles (defined as > or = 120 mIU/mL; 2720 mIU/mL; 95% CI, 1423-5198 mIU/mL), 96% achieving optimal antibody concentrations to meningococcus C (defined as > or = 1:8; 1:1000; 95% CI, 1:483-1:2064), and 85% achieving optimal antibody concentrations to all the 3 poliovirus serotypes (defined as > or = 1:8). For the majority of subjects, protection persisted for at least 12 months after vaccination.

CONCLUSION

Revaccination of children after standard chemotherapy is important, and protection can be achieved in the majority of these children using a simple schedule of 1 vaccine dose at 6 months after completion of leukemia therapy.

Revaccination with measles, tetanus, poliovirus, Haemophilus influenzae type B, meningococcus C, and pneumococcus vaccines in children after hematopoietic stem cell transplantation

BACKGROUND

There is a decrease in antibody levels after hematopoietic stem cell transplant (HSCT), and such patients may be at increased risk of acquiring vaccine-preventable infection. A simple and validated revaccination schedule is required. The aim of this study was to evaluate the immunogenicity of a revaccination schedule for pediatric HSCT recipients.

METHODS

Thirty-eight children (age, 1-18 years) who had undergone autologous or allogeneic HSCT for malignant diseases were recruited. All children received vaccinations in accordance with a predefined schedule. Antibody concentrations were measured before and 2-4 weeks after vaccination against tetanus; Haemophilus influenzae type b (Hib); meningococcus C; measles; poliovirus serotypes 1, 2, and 3; and 9 pneumococcus serotypes.

RESULTS

Before vaccination, protective antibody levels were found for tetanus in 95% of patients (geometric mean concentration [GMC], 0.07 IU/mL; 95% CI, 0.05-0.1 IU/mL), for Hib in 63% (GMC, 0.34 microg/mL; 95% CI, 0.21-0.57 microg/mL), for measles in 60% (GMC, 102 mIU/mL; 95% CI, 41-253 mIU/mL), for meningococcus C in 11% (geometric mean titer [GMT], 1:4; 95% CI, 1:2-1:8.4), for all 3 poliovirus serotypes in 29%, and for all 9 pneumococcal serotypes in 0%. Vaccination resulted in a significant increase (P < or = .05) in antibody levels to each vaccine antigen studied, with 100% of patients achieving protection against tetanus (GMC, 2.2 IU/mL; 95% CI, 1.8-2.7 IU/mL), 100% achieving protection against Hib (GMC, 8.4 microg/mL; 95% CI, 7.6-9.3 microg/mL), 100% achieving protection against measles (GMC, 2435 mIU/mL; 95% CI, 1724-3439 mIU/mL), 100% achieving protection against meningococcus C (GMT, 1:5706; 95% CI, 1:3510-1:9272), 92% achieving protection against the 3 poliovirus serotypes, and > or = 80% achieving protection against each of the heptavalent pneumococcal conjugate vaccine-associated serotypes. No factors relevant to age, underlying disease, or treatment type were found to significantly influence responses.

CONCLUSION

Revaccination of pediatric HSCT recipients in accordance with this revaccination schedule provides a high level of protection against these vaccine-preventable diseases.

Effect of increased lung volume on sleep disordered breathing in patients with sleep apnoea

BACKGROUND

Previous studies have shown that changes in lung volume influence upper airway size and resistance, particularly in patients with obstructive sleep apnoea (OSA), and that continuous positive airway pressure (CPAP) requirements decrease when the lung volume is increased. We sought to determine the effect of a constant lung volume increase on sleep disordered breathing during non-REM sleep.

METHODS

Twelve subjects with OSA were studied during non-REM sleep in a rigid head-out shell equipped with a positive/negative pressure attachment for manipulation of extrathoracic pressure. The increase in lung volume due to CPAP (at a therapeutic level) was determined with four magnetometer coils placed on the chest wall and abdomen. CPAP was then stopped and the subjects were studied for 1 hour in three conditions (in random order): (1) no treatment (baseline); (2) at "CPAP lung volume", with the increased lung volume being reproduced by negative extrathoracic pressure alone (lung volume 1, LV1); and (3) 500 ml above the CPAP lung volume(lung volume 2, LV2).

RESULTS

The mean (SE) apnoea/hypopnoea index (AHI) for baseline, LV1, and LV2, respectively, was 62.3 (10.2), 37.2 (5.0), and 31.2 (6.7) events per hour (p = 0.009); the 3% oxygen desaturation index was 43.0 (10.1), 16.1 (5.4), and 12.3 (5.3) events per hour (p = 0.002); and the mean oxygen saturation was 95.4 (0.3)%, 96.0 (0.2)%, 96.3 (0.3)%, respectively (p = 0.001).

CONCLUSION

An increase in lung volume causes a substantial decrease in sleep disordered breathing in patients with OSA during non-REM sleep.

Study of ground water quality for irrigation in some villages of Surat District, Gujarat (India)

40 ground water samples of 10 villages in Surat district, Gujarat (India) were analyzed for their suitability for irrigation purpose. The mean values of 4 samples taken from each village have been reported in the present study. Ground water of the study area was classified according to sodium adsorption ratio (SAR), percentage sodium (PS), residual sodium carbonate (RSC), Kelley's ratio and electrical conductivity. The value of sodium adsorption ratio indicated that majority of samples (9 out of 10) fall in low sodium hazard category. As per classification made by Wilcox (1948), on the basis of percentage sodium and electrical conductivity, only 1 sample (Vesu) not found suitable for irrigation purpose while only 1 sample (Gaviyar) found in good category. The remaining 8 samples were in good to permissible and permissible to doubtful category. Ground water was also classified according to the classification of United States Salinity Laboratory based on sodium and salinity hazard.

Cytomegalovirus reactivation in pediatric hemopoietic progenitors transplant: a retrospective study on the risk factors and the efficacy of treatment

Cytomegalovirus (CMV) disease is an important infectious complication after allogeneic hemopoietic progenitors transplant (HPT), but few data are available in children. To investigate the factors influencing CMV reactivation, subsequent relapses of positive antigenemia, and the development of organ disease in children, the authors retrospectively analyzed 108 children who received allogeneic HPT for malignant conditions at one center. Of these, 41 were CMV serology positive (donor or recipient) before HPT. All those with CMV-positive serology received high-dose acyclovir in conjunction with weekly CMV phosphoprotein-pp65 antigen monitoring of the peripheral blood during the first 3 months. Those with CMV reactivation (positive antigenemia) received preemptive treatment with ganciclovir and/or foscarnet to prevent CMV disease. The incidence of positive antigenemia in this cohort was 41.5% at a mean of 44 +/- 31.6 days after HPT. Two patients (4.9%) subsequently developed late CMV disease. Recipient CMV status was significantly (P = 0.0001) more relevant to reactivation than donor status. Reactivations were significantly more common in single recipient seropositive than double (donor and recipient) positive pairs (P = 0.05). Reactivations were significantly more common in recipients of unrelated donor grafts than matched-related donor grafts (P = 0.025). Reactivations also occurred significantly more in T-cell-depleted graft recipients (P = 0.004) than recipients of unmanipulated grafts. The subsequent development of disease was more common in a CMV-seropositive recipient receiving a CMV-seronegative, T-cell-depleted, unrelated donor graft, and after transplantation receiving treatment for acute graft-versus-host disease. Patients with identified high risk factors for CMV reactivation and disease should be monitored by CMV PCR, and early preemptive treatment should be instigated to prevent the development of disease.

Varicella-zoster reactivation in a patient receiving routine revaccinations after an allogeneic hemopoietic progenitors transplant

Primary varicella-zoster virus (VZV) infection and herpes zoster are important infectious complications after an allogeneic hemopoietic progenitors transplant (HPT). The authors describe a girl with second relapse of acute lymphoblastic leukemia who received an HPT at age 13 years. Two years after the HPT she started a revaccination program of routine childhood vaccines. With each course of vaccines she developed herpes zoster of the C6 dermatome, initially with the rash and later zoster sine herpete. The vaccinations appear to have triggered VZV reactivation by vaccine-induced immunomodulation in this HPT recipient.

Linkage of serum leptin levels in families with sleep apnea

OBJECTIVE

To identify regions on the genome linked to plasma leptin levels.

DESIGN

Full genome scan with 402 microsatellite markers, spaced approximately 10 cM apart. Data were analyzed using the Haseman-Elston regression linkage analysis.

SUBJECTS

A total of 160 sibling pairs from 59 predominantly African American, obese families recruited to participate in a genetic-epidemiological study of obstructive sleep apnea.

MEASUREMENTS

Serum leptin levels adjusted for age, sex, race and body mass index (BMI).

RESULTS

Suggestive linkage peaks were observed on chromosomes 2 (P=0.00170; marker D2S1384), 3 (P=0.00007; marker D3S3034), 4 (P=0.00020; marker D4S1652) and 21 (P=0.00053; marker D21s1411).

CONCLUSION

The peak on chromosome 3 is near the gene for glycogensynthase kinase 2 beta, an important factor in glucose homeostasis. Linkage was generally stronger after BMI adjustment, suggesting the potential influence of a number of metabolic pathways on leptin levels other than those that directly determine obesity levels. The evidence of linkage for leptin levels is consistent with prior linkage analyses for cholesterol, hypertension and other metabolic phenotypes.

High-dose granulocyte colony-stimulating factor mobilizes a higher proportion of early CD34(+) CD33(-) hemopoietic progenitors in children receiving treatment for solid tumors

A relationship between dose of granulocyte colony-stimulating factor (G-CSF) and maturational stage of the progenitors mobilized in healthy adult donors has been suggested. In this study we characterize the progenitors mobilized by 2 different dosages of G-CSF in children receiving autologous grafts after intensive treatment for solid tumors.