Influenza epidemics: The role of allergists-immunologists.

OBJECTIVE: To review influenza epidemics and pandemics for practicing allergists-immunologists. DATA SOURCES: English-language articles published in PubMed from 1990 to present with relevance to allergic disorders and articles cited by or similar to these articles. STUDY SELECTIONS: A total of 472 articles were identified from PubMed. Two independent reviewers appraised the titles for relevance. RESULTS: A total of 212 relevant articles were selected. Additional articles and government websites increased the number to 295 relevant citations. CONCLUSION: Influenza epidemics and pandemics have recurred throughout history. Patients with asthma and immunodeficiency are at an increased risk. Nonpharmaceutical interventions, vaccination, and neuraminidase inhibitors are key strategies for the prevention and treatment of influenza epidemics/pandemics. Allergists play a vital role in protecting high-risk groups and increasing influenza vaccination coverage.

An Atypical Case of Thrombotic Microangiopathy Secondary to Acute Pancreatitis.

Thrombotic microangiopathies (TMAs) are a group of disorders characterized by microangiopathic hemolytic anemia, thrombocytopenia, and end-organ damage. It can often be challenging to determine the underlying etiology. Our patient presented with acute pancreatitis and later developed thrombocytopenia and hemolytic anemia, along with acute renal failure. A working diagnosis of an atypical hemolytic uremic syndrome was made; however, he improved clinically and eculizumab was not started. Workup for the atypical hemolytic uremic syndrome was unrevealing. The authors propose that the pancreatitis triggered a secondary TMA, which although rare, has previously been described in the literature. This case illustrates the diagnostic and therapeutic challenges associated with TMAs.

The Brain-to-Pancreatic Islet Neuronal Map Reveals Differential Glucose Regulation From Distinct Hypothalamic Regions.

The brain influences glucose homeostasis, partly by supplemental control over insulin and glucagon secretion. Without this central regulation, diabetes and its complications can ensue. Yet, the neuronal network linking to pancreatic islets has never been fully mapped. Here, we refine this map using pseudorabies virus (PRV) retrograde tracing, indicating that the pancreatic islets are innervated by efferent circuits that emanate from the hypothalamus. We found that the hypothalamic arcuate nucleus (ARC), ventromedial nucleus (VMN), and lateral hypothalamic area (LHA) significantly overlap PRV and the physiological glucose-sensing enzyme glucokinase. Then, experimentally lowering glucose sensing, specifically in the ARC, resulted in glucose intolerance due to deficient insulin secretion and no significant effect in the VMN, but in the LHA it resulted in a lowering of the glucose threshold that improved glucose tolerance and/or improved insulin sensitivity, with an exaggerated counter-regulatory response for glucagon secretion. No significant effect on insulin sensitivity or metabolic homeostasis was noted. Thus, these data reveal novel direct neuronal effects on pancreatic islets and also render a functional validation of the brain-to-islet neuronal map. They also demonstrate that distinct regions of the hypothalamus differentially control insulin and glucagon secretion, potentially in partnership to help maintain glucose homeostasis and guard against hypoglycemia.