Early diagnosis of Malan syndrome in an infant presenting with macrocephaly

We present an infant with persistent macrocephaly and developmental delay. There is a wide range of differential diagnoses for this presentation, including many rare genetic conditions. Here, a diagnosis of Malan syndrome was made-a rare overgrowth syndrome caused by haploinsufficiency of NFIX and features affecting the neurological and musculoskeletal systems. Improvements in genomic medicine technologies and clinical services have revolutionised the way clinicians diagnose rare diseases. We highlight the importance of early genetic testing, particularly if there are red flag features such as developmental delay, and the need for a coordinated strategy to improve the management of rare diseases like Malan syndrome.

BCG-induced non-specific effects on heterologous infectious disease in Ugandan neonates: an investigator-blind randomised controlled trial

BACKGROUND

Trials done in infants with low birthweight in west Africa suggest that BCG vaccination reduces all-cause mortality in the neonatal period, probably because of heterologous protection against non-tuberculous infections. This study investigated whether BCG alters all-cause infectious disease morbidity in healthy infants in a different high-mortality setting, and explored whether the changes are mediated via trained innate immunity.

METHODS

This was an investigator-blind, randomised, controlled trial done at one hospital in Entebbe, Uganda. Infants who were born unwell (ie, those who were not well enough to be discharged directly home from the labour ward because they required medical intervention), with major congenital malformations, to mothers with HIV, into families with known or suspected tuberculosis, or for whom cord blood samples could not be taken, were excluded from the study. Any other infant well enough to be discharged directly from the labour ward was eligible for inclusion, with no limitation on gestational age or birthweight. Participants were recruited at birth and randomly assigned (1:1) to receive standard dose BCG 1331 (BCG-Danish) on the day of birth or at age 6 weeks (computer-generated randomisation, block sizes of 24, stratified by sex). Investigators and clinicians were masked to group assignment; parents were not masked. Participants were clinically followed up to age 10 weeks and contributed blood samples to one of three immunological substudies. The primary clinical outcome was physician-diagnosed non-tuberculous infectious disease incidence. Primary immunological outcomes were histone trimethylation at the promoter region of TNF, IL6, and IL1B; ex-vivo production of TNF, IL-6, IL-1β, IL-10, and IFNγ after heterologous stimulation; and transferrin saturation and hepcidin levels. All outcomes were analysed in the modified intention-to-treat population of all randomly assigned participants except those whose for whom consent was withdrawn. This trial is registered with the International Standard Randomised Controlled Trial Number registry (#59683017).

FINDINGS

Between Sept 25, 2014, and July 31, 2015, 560 participants were enrolled and randomly assigned to receive BCG at birth (n=280) or age 6 weeks (n=280). 12 participants assigned to receive BCG at birth and 11 participants assigned to receive BCG at age 6 weeks were withdrawn from the study by their parents shortly after randomisation and were not included in analyses. During the first 6 weeks of life before the infants in the delayed vaccination group received BCG vaccination, physician-diagnosed non-tuberculous infectious disease incidence was lower in infants in the BCG at birth group than in the delayed group (98 presentations in the BCG at birth group vs 129 in the delayed BCG group; hazard ratio [HR] 0·71 [95% CI 0·53-0·95], p=0·023). After BCG in the delayed group (ie, during the age 6-10 weeks follow-up), there was no significant difference in non-tuberculous infectious disease incidence between the groups (88 presentations vs 76 presentations; HR 1·10 [0·87-1·40], p=0·62). BCG at birth inhibited the increase in histone trimethylation at the TNF promoter in peripheral blood mononuclear cells occurring in the first 6 weeks of life. H3K4me3 geometric mean fold-increases were 3·1 times lower at the TNF promoter (p=0·018), 2·5 times lower at the IL6 promoter (p=0·20), and 3·1 times lower at the IL1B promoter (p=0·082) and H3K9me3 geometric mean fold-increases were 8·9 times lower at the TNF promoter (p=0·0046), 1·2 times lower at the IL6 promoter (p=0·75), and 4·6 times lower at the IL1B promoter (p=0·068), in BCG-vaccinated (BCG at birth group) versus BCG-naive (delayed BCG group) infants. No clear effect of BCG on ex-vivo production of TNF, IL-6, IL-1β, IL-10, and IFNγ after heterologous stimulation, or transferrin saturation and hepcidin concentration, was detected (geometric mean ratios between 0·68 and 1·68; p≥0·038 for all comparisons).

INTERPRETATION

BCG vaccination protects against non-tuberculous infectious disease during the neonatal period, in addition to having tuberculosis-specific effects. Prioritisation of BCG on the first day of life in high-mortality settings might have significant public-health benefits through reductions in all-cause infectious morbidity and mortality.

FUNDING

Wellcome Trust.

TRANSLATIONS

For the Luganda and Swahili translations of the abstract see Supplementary Materials section.

Antituberculosis BCG vaccination: more reasons for varying innate and adaptive immune responses

Bacillus Calmette-Guérin (BCG) vaccination induces variable protection against pulmonary tuberculosis (TB), and a more effective TB vaccine is needed. The potential for BCG to provide protection against heterologous infections, by induction of innate immune memory, is increasingly recognized. These nonspecific responses may substantially benefit public health, but are also variable. In this issue of the JCI, Koeken and de Bree et al. report that BCG reduces circulating inflammatory markers in males but not in females, while de Bree and Mouritis et al. describe how diurnal rhythms affect the degree of BCG-induced innate memory. These studies further delineate factors that influence the magnitude of responses to BCG and may be crucial to harnessing its potential benefits.

Post-immunization leucocytosis and its implications for the management of febrile infants

Aims

Clinical guidelines for management of infants with fever but no evident focus of infection recommend that those aged 1–3 months with a white cell count >15 × 10⁹/l have a full septic screen and be admitted for parenteral antibiotics. However, there is limited information about leucocyte changes following routine immunization, a common cause of fever. We investigated white cell counts shortly after routine immunization in Ugandan infants under 3 months of age.

Methods

White cell counts were measured in 212 healthy infants following routine immunizations (DTwP-HepB-Hib, oral polio and pneumococcal conjugate 7 vaccines) received prior to 3 months of age.

Results

Mean leucocyte counts increased from 9.03 × 10⁹/l (95% confidence interval 8.59–9.47 × 10⁹/l) pre-immunizations to 16.46 × 10⁹/l (15.4–17.52 × 10⁹/l) at one-day post-immunizations at 6 weeks of age, and 15.21 × 10⁹/l (14.07–16.36 × 10⁹/l) at one-day post-immunizations at 10 weeks of age. The leucocytosis was primarily a neutrophilia, with neutrophil percentages one-day post-immunization of 49% at 6 weeks of age and 46% at 10 weeks of age. White cell parameters returned to baseline by two-days post-immunization. No participant received antibiotics when presenting with isolated fever post-immunization and all remained well at follow-up.

Conclusions

In our study almost half the children <3 months old presenting with fever but no evident focus of infection at one-day post-immunization met commonly used criteria for full septic screen and admission for parenteral antibiotics, despite having no serious bacterial infection. These findings add to the growing body of literature that questions the utility of white blood cell measurement in identification of young infants at risk of serious bacterial infections, particularly in the context of recent immunizations, and suggest that further exploration of the effect of different immunization regimes on white cell counts is needed.

This observational work was nested within a clinical trial, registration number ISRCTN59683017.

They Are What You Eat: Can Nutritional Factors during Gestation and Early Infancy Modulate the Neonatal Immune Response?

The ontogeny of the human immune system is sensitive to nutrition even in the very early embryo, with both deficiency and excess of macro- and micronutrients being potentially detrimental. Neonates are particularly vulnerable to infectious disease due to the immaturity of the immune system and modulation of nutritional immunity may play a role in this sensitivity. This review examines whether nutrition around the time of conception, throughout pregnancy, and in early neonatal life may impact on the developing infant immune system.

Posttraumatic stress following spinal cord injury: a systematic review of risk and vulnerability factors

OBJECTIVES

To summarise quantitatively the available evidence relating to pretraumatic, peritraumatic and posttraumatic characteristics that may increase or decrease the risk of developing posttraumatic stress disorder (PTSD) following spinal cord injury (SCI).

STUDY DESIGN

Systematic review.

METHODS

Seventeen studies were identified from the PubMed, PsycInfo, Embase, Scopus, CINAHL, Web of Science and PILOTS databases. Effect size estimates (r) with associated 95% confidence intervals (CIs), P-values and fail-safe Ns were calculated.

RESULTS

Individual studies reported medium-to-large associations between factors that occurred before (psychiatric history r=0.48 (95% CI, 0.23-0.79) P=0.01) or at the time of injury (tetraplegia r=-0.36 (95% CI, -0.50 to -0.19) P<0.01). Postinjury factors had the strongest pooled effects: depressed mood (r_w=0.64, (95% CI, 0.54-0.72)), negative appraisals (r_w=0.63 (95% CI, 0.52-0.72)), distress (r_w=0.57 (95% CI, 0.50-0.62)), anxiety (r_w=0.56 (95% CI, 0.49-0.61)) and pain severity (r_w=0.35 (95% CI, 0.27-0.43)) were consistently related to worsening PTSD symptoms (P<0.01). Level of injury significantly correlated with current PTSD severity for veteran populations (Q_B (1)=18.25, P<0.001), although this was based on limited data.

CONCLUSION

Combinations of peri- and post-injury factors appear to be influential in the development of PTSD among persons with SCI. Further studies are needed to extrapolate these findings to the broader spinal cord-injured population. More longitudinal research, driven by multicausal models of causation such as the diathesis-stress model, is also needed to determine the temporality of PTSD risk factors.

Maternal BCG scar is associated with increased infant proinflammatory immune responses

Introduction

Prenatal exposures such as infections and immunisation may influence infant responses. We had an opportunity to undertake an analysis of innate responses in infants within the context of a study investigating the effects of maternal mycobacterial exposures and infection on BCG vaccine-induced responses in Ugandan infants.

Material and methods

Maternal and cord blood samples from 29 mother-infant pairs were stimulated with innate stimuli for 24 h and cytokines and chemokines in supernatants were measured using the Luminex® assay. The associations between maternal latent Mycobacterium tuberculosis infection (LTBI), maternal BCG scar (adjusted for each other’s effect) and infant responses were examined using linear regression. Principal Component Analysis (PCA) was used to assess patterns of cytokine and chemokine responses. Gene expression profiles for pathways associated with maternal LTBI and with maternal BCG scar were examined using samples collected at one (n = 42) and six (n = 51) weeks after BCG immunisation using microarray.

Results

Maternal LTBI was positively associated with infant IP-10 responses with an adjusted geometric mean ratio (aGMR) [95% confidence interval (CI)] of 5.10 [1.21, 21.48]. Maternal BCG scar showed strong and consistent associations with IFN-γ (aGMR 2.69 [1.15, 6.17]), IL-12p70 (1.95 [1.10, 3.55]), IL-10 (1.82 [1.07, 3.09]), VEGF (3.55 [1.07, 11.48]) and IP-10 (6.76 [1.17, 38.02]). Further assessment of the associations using PCA showed no differences for maternal LTBI, but maternal BCG scar was associated with higher scores for principal component (PC) 1 (median level of scores: 1.44 in scar-positive versus −0.94 in scar-negative, p = 0.020) in the infants. PC1 represented a controlled proinflammatory response. Interferon and inflammation response pathways were up-regulated in infants of mothers with LTBI at six weeks, and in infants of mothers with a BCG scar at one and six weeks after BCG immunisation.

Conclusions

Maternal BCG scar had a stronger association with infant responses than maternal LTBI, with an increased proinflammatory immune profile.

Evidence for a downward secular trend in age of menarche in a rural Gambian population

Menarcheal age is a key indicator of female maturity and development. Studies in many countries have reported a downward secular trend in age of menarche over the past century. This study presents data gained using the ‘status quo’ method and interval regression to estimate median menarcheal age of girls in a rural Gambian community. Cross-sectional studies carried out in 1989, 2000 and 2008 revealed a median menarcheal age of 16.06 (95% CI 15.67–16.45), 15.03 (95% CI 14.76–15.30) and 14.90 (95% CI 14.52–15.28), respectively. The average rate of decline of median age of menarche was amongst the most rapid yet reported, at 0.65 years of age per decade (p < 0.00001). There was no evidence for a change in the rate of decline over the two decades studied. These results probably reflect ongoing socio-economic development within the region.

Characteristics of voluntary visual sampling of the environment for safe locomotion over different terrains

The characteristics of visual sampling required for successful locomotion over various terrains is the focus of this work. In the first experiment we directly address the role of continuous visual monitoring of the environment in guiding locomotion by allowing the subjects to choose when and where to take a visual sample of the terrain and examine the effects of different terrains on characteristics of visual sampling. Young subjects walked over travel paths of varying difficulties while wearing opaque liquid crystal eyeglasses and pressed a hand-held switch to make the glasses transparent when they needed to sample the environment. Travel time and visual sampling characteristics were recorded. Results show that intermittent sampling (less than 50%) of the environment is adequate for safe locomotion, even over a novel travel path. The frequency, duration and timing of visual samples are dependent on terrain characteristics. Visual sampling of the environment is unaffected by preview restriction of the travel path and is increased when specific foot placement is required and there is a potential hazard in the travel path. In the second experiment we dissociated steering control and obstacle avoidance from specific foot placement and examined visual sampling demands prior to the initiation of the swing phase and during the swing phase. The results show that steering control and obstacle avoidance do influence the visual sampling time, which is scaled to the magnitude of change. Vision was used in a feedforward control mode to plan for and initiate appropriate changes in the swing limb trajectory: its use during the swing phase to provide on-line control was minimal.

Locomotor Patterns of the Leading and the Trailing Limbs as Solid and Fragile Obstacles Are Stepped Over: Some Insights Into the Role of Vision During Locomotion

The issues explored in this article are the role of exproprioceptive input and the nature of exteroceptive input provided by the visual system in the control of limb elevation as obstacles are stepped over during locomotion. In the first experiment, the differences in limb trajectory of movements over solid and fragile obstacles of similar dimensions were examined. Subjects increased their toe clearance, vertical position of the hip, and the hip vertical velocity when going over a fragile obstacle with the leading limb. This suggests that in addition to visually observable properties of obstacles such as height or width, other properties, such as rigidity or fragility, which may be classified as visually inferred, also influence the limb trajectory. Part of the first and the second experiment was focused on understanding differences in leading limb and trailing limb trajectory over obstacles. The toe clearance of the trailing limb was lower for smaller obstacles. There was no consistent correlation between the toe clearance values of the leading and trailing limbs. The variability in toe clearance was higher for the trailing limb, which is attributable to lack of visual exproprioceptive input about trailing limb movements and to the shorter time available following toe-off to fine-tune the trailing limb trajectory. Because the body center of mass is moving toward the supporting foot when the trailing limb goes over obstacles and the trailing limb foot is moving up, the chances of a trip are minimized and recovery from an unexpected trip are more likely. These results highlight the role of exproprioceptive input provided by the visual system and possible cognitive influences on the limb trajectory as one travels over uneven terrains.

Age-related changes in balance control system: initiation of stepping

The balance control system of a group of healthy and fit, young and elderly subjects was studied during the initiation of stepping in one of three directions: forward, sideways, and backwards in response to a light cue. The performance of these movements requires shifting support from two to one foot, moving the centre of mass outside the initial base of support and creating a new support configuration. By recording and analysing the vertical ground reaction force beneath the subject's stepping foot, we were able to examine the two phases prior to limb lift-off for stepping: reaction time and weight transfer time. Both reaction time and weight transfer time increased with age: The elderly subjects had a proportionately larger increase in weight transfer time compared to the reaction time. The peak force generated showed an age by stepping direction effect: the elderly had a significantly lower peak force for the forwards stepping compared to the younger subjects. The larger increase in weight transfer results in a slower stepping response. Since a stepping task is often recruited to avoid a fall, the increase in response execution time can have undesirable consequences.