Encephalopathy with Guillain-Barré syndrome: seek a different cause.

A 30-year-old woman developed symptoms, signs and neurophysiology consistent with Guillain-Barré syndrome and was admitted to the neurosciences intensive care unit owing to respiratory compromise. Here, she received a clonidine infusion for agitation, complicated by a minor hypotensive episode, following which she became unconscious. MR scan of the brain showed changes compatible with hypoxic brain injury. Urinary amino acids showed increased urinary α-ketoglutarate. Genetic testing using whole-exome sequencing identified pathogenic variants in the SLC13A3 gene known to be associated with an acute reversible leukoencephalopathy with increased urinary α-ketoglutarate. The case highlights the importance of considering inborn errors of metabolism in cases of unexplained encephalopathy.

Cardiovascular-related death in infancy and childhood: a clinicopathological study of two referral institutions in England.

To review post-mortem findings among deaths presenting as sudden and/or unexpected deaths in two centers in the UK during a 16-year period in order to identify those related to cardiovascular conditions. The post-mortem databases of two tertiary referral institutions were searched, and all reports were reviewed. Histological features and results of ancillary investigations were noted. All cases of sudden and/or unexpected cardiac deaths (SCD) between 2003 and 2018 were identified. The study was PRISMA compliant and approved by clinical governance. 68/1129 cases of SCD (6.0%) were identified in one center and 83/753 cases (11%) in the other. These 151 cases constituted the study cohort. The mean annual incidence of SCD was 0.3 per 100,000 persons/annum. The three most prevalent groups of cardiac pathology were cardiac malformations (51/151; 33.8%), cardiomyopathies (32/151; 21.2%), and myocarditis (31/151; 20.5%). Mean age at death was 3.4 years. Prematurity was predominantly associated with deaths related to cardiac malformations (p < 0.001). Symptoms had been present for a mean of 3.8, 3.0, and 3.5 days before death for myocarditis, cardiomyopathy, and cardiac malformations/complications post-surgery. This retrospective comparative study represents the largest autopsy series of SCD in infants and children in the UK. Some entities are very infrequent. Several diseases could have been identified earlier in life allowing for the possibility of intervention. Limitation includes the retrospective nature of the study and that, as arrhythmogenic gene mutations are not yet routinely performed in unexplained deaths, the incidence of SCD in infants and children is most likely underestimated.

Pioneer neutrophils release chromatin within in vivo swarms.

Neutrophils are rapidly recruited to inflammatory sites where their coordinated migration forms clusters, a process termed neutrophil swarming. The factors that modulate early stages of neutrophil swarming are not fully understood, requiring the development of new in vivo models. Using transgenic zebrafish larvae to study endogenous neutrophil migration in a tissue damage model, we demonstrate that neutrophil swarming is a conserved process in zebrafish immunity, sharing essential features with mammalian systems. We show that neutrophil swarms initially develop around an individual pioneer neutrophil. We observed the violent release of extracellular cytoplasmic and nuclear fragments by the pioneer and early swarming neutrophils. By combining in vitro and in vivo approaches to study essential components of neutrophil extracellular traps (NETs), we provide in-depth characterisation and high-resolution imaging of the composition and morphology of these release events. Using a photoconversion approach to track neutrophils within developing swarms, we identify that the fate of swarm-initiating pioneer neutrophils involves extracellular chromatin release and that the key NET components gasdermin, neutrophil elastase, and myeloperoxidase are required for the swarming process. Together our findings demonstrate that release of cellular components by pioneer neutrophils is an initial step in neutrophil swarming at sites of tissue injury.

Hippocampal abnormalities and seizures: a 16-year single center review of sudden unexpected death in childhood, sudden unexpected death in epilepsy and SIDS.

Sudden Unexpected Death in Childhood (SUDC) is the unexplained death of children aged between 1 and 18 years old. Hippocampal abnormalities have previously been described in Sudden Unexpected Death in Epilepsy (SUDEP) and it is possible that SUDC shares similar pathogenic mechanisms with SUDEP. Our aim was to determine the prevalence of hippocampal abnormalities, history of seizures and demographic features in our caseload of SUDC, SUDEP and SIDS cases. A review of post-mortem reports from 2003 to 2018 was carried out to identify cases of SUDC, SUDEP and SIDS. Histological evidence of hippocampal abnormalities, patient demographics (age, gender), sleeping position, and past medical history (history of seizures and illness 72 hours prior to death) were recorded. Statistical analysis was performed to compare the three groups. 48 SUDC, 18 SUDEP and 358 SIDS cases were identified. Hippocampal abnormalities associated with temporal lobe epilepsy were found in 44.4% of SUDC cases. 5/15 SUDC cases with a history of seizures demonstrated hippocampal abnormalities. SUDC cases were also more likely to be found prone compared to SIDS cases. In comparison with SIDS, both SUDC and SUDEP cases were more likely to demonstrate hippocampal abnormalities (SUDC: (OR = 9.4, 95% CI: 3.1-29.1, p < 0.001; SUDEP: OR = 35.4, 95% CI: 8.3-151.5, p < 0.001). We found a potential link between hippocampal abnormalities and epileptic seizures in SUDC. A concerted effort should be directed towards consistent sampling and standardized description of the hippocampus and clinical correlation with a history of seizures/epilepsy in postmortem reports.