Leukemoid reaction in minocycline-induced drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome: A brief report.

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is an idiosyncratic drug reaction hallmarked by cutaneous eruption, fever, lymphadenopathy, multiorgan involvement, and hematological abnormalities, most often eosinophilia and atypical lymphocytosis. Leukemoid reactions have rarely been described in DRESS syndrome and here we describe a 16-year-old male who was admitted to the hospital with DRESS syndrome due to minocycline, who had a severe leukocytosis up to 52.08 K/µL. He improved with cessation of minocycline and initiation of systemic steroids. We report this case to add to the literature on hematological abnormalities in pediatric DRESS syndrome.

Oxidative Stress Underlies the Ischemia/Reperfusion-Induced Internalization and Degradation of AMPA Receptors.

Stroke is the fifth leading cause of death annually in the United States. Ischemic stroke occurs when a blood vessel supplying the brain is occluded. The hippocampus is particularly susceptible to AMPA receptor-mediated delayed neuronal death as a result of ischemic/reperfusion injury. AMPA receptors composed of a GluA2 subunit are impermeable to calcium due to a post-transcriptional modification in the channel pore of the GluA2 subunit. GluA2 undergoes internalization and is subsequently degraded following ischemia/reperfusion. The subsequent increase in the expression of GluA2-lacking, Ca2+-permeable AMPARs results in excitotoxicity and eventually delayed neuronal death. Following ischemia/reperfusion, there is increased production of superoxide radicals. This study describes how the internalization and degradation of GluA1 and GluA2 AMPAR subunits following ischemia/reperfusion is mediated through an oxidative stress signaling cascade. U251-MG cells were transiently transfected with fluorescently tagged GluA1 and GluA2, and different Rab proteins to observe AMPAR endocytic trafficking following oxygen glucose-deprivation/reperfusion (OGD/R), an in vitro model for ischemia/reperfusion. Pretreatment with Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin (MnTMPyP), a superoxide dismutase mimetic, ameliorated the OGD/R-induced, but not agonist-induced, internalization and degradation of GluA1 and GluA2 AMPAR subunits. Specifically, MnTMPyP prevented the increased colocalization of GluA1 and GluA2 with Rab5, an early endosomal marker, and with Rab7, a late endosomal marker, but did not affect the colocalization of GluA1 with Rab11, a marker for recycling endosomes. These data indicate that oxidative stress may play a vital role in AMPAR-mediated cell death following ischemic/reperfusion injury.