Spontaneous retroperitoneal hemorrhage in dialysis: a presentation of 5 cases and review of the literature.

BACKGROUND: Spontaneous retroperitoneal hemorrhage (SRH) is a rare but potentially fatal entity. Despite published case reports of SRH in dialysis, little systematic information is available. METHODS: Report of 5 cases and review of MEDLINE database from 1971 until 2008. RESULTS: Incidence of SRH in our unit was 0.86 cases per 100 patients; annual incidence rate 8/10,000 patients. We identified 34 publications, comprising 55 cases. The existing cases and the 5 reported were analyzed: 74.5 % male, average age 53.3 years (range 27-78), average time on dialysis 7.1 years (range 3 weeks-27.5 years), 95% on hemodialysis and 5% on peritoneal dialysis. There was significant heterogeneity in clinical presentation. The kidney was the most commonly reported origin (87.8%), and acquired cystic kidney disease (ACKD) was the most frequent underlying cause. 91.8% received some kind of anticoagulation. Treatment was conservative, included angioembolization or surgery in 33.3%, 17.6% and 49% of the cases respectively. Mortality rate was 18.3%. CONCLUSIONS: More than 85% of SRH in dialysis had a renal cause, ACKD being predominant. The complication occurs mainly in the HD modality, possibly in relation to anticoagulation. There is no evidence that screening of ACKD is of benefit predicting SRH. Therefore, awareness of ACKD as a manifestation of ESRD patients and its risk of bleeding is necessary. Because of the summation of risk factors that appears in the population on dialysis, SRH should be considered in the differential diagnosis of unexplained pain before drop in blood pressure or hematocrit occurs.

[Intracranial cavernous angioma.]. / Angiomas cavernosos intracraneales.

We report the case of a 13-year-old boy who presented at the emergency department for nausea and vomiting with ataxia and dissymmetry. He had strabismus as a consequence of palsy of the VI cranial nerve when 9 months old that was attributed to an allergy to penicillin. He had no relevant family history. Urgent CT and posterior MRI examination showed multiple supratentorial and infratentorial cavernous angiomas, one of which was located in the brainstem and presented acute hemorrhage, causing the symptoms. Angiography performed later showed no evidence of vascular malformations. The patient was initially managed conservatively, but the cavernous angioma in the brainstem was surgically extirpated after the patient's condition progressively worsened.

Enhancing violations of Leggett-Garg inequalities in nonequilibrium correlated many-body systems by interactions and decoherence.

We identify different schemes to enhance the violation of Leggett-Garg inequalities in open many-body systems. Considering a nonequilibrium archetypical setup of quantum transport, we show that particle interactions control the direction and amplitude of maximal violation, and that in the strongly-interacting and strongly-driven regime bulk dephasing enhances the violation. Through an analytical study of a minimal model we unravel the basic ingredients to explain this decoherence-enhanced quantumness, illustrating that such an effect emerges in a wide variety of systems.

Coexistence of energy diffusion and local thermalization in nonequilibrium XXZ spin chains with integrability breaking.

In this work we analyze the simultaneous emergence of diffusive energy transport and local thermalization in a nonequilibrium one-dimensional quantum system, as a result of integrability breaking. Specifically, we discuss the local properties of the steady state induced by thermal boundary driving in a XXZ spin chain with staggered magnetic field. By means of efficient large-scale matrix product simulations of the equation of motion of the system, we calculate its steady state in the long-time limit. We start by discussing the energy transport supported by the system, finding it to be ballistic in the integrable limit and diffusive when the staggered field is finite. Subsequently, we examine the reduced density operators of neighboring sites and find that for large systems they are well approximated by local thermal states of the underlying Hamiltonian in the nonintegrable regime, even for weak staggered fields. In the integrable limit, on the other hand, this behavior is lost, and the identification of local temperatures is no longer possible. Our results agree with the intuitive connection between energy diffusion and thermalization.