Pancytopenia induced by hypothermia

Increasing Seizures, Encephalopathy, and Hypothermia in an 18-Year-Old Woman

ABSTRACT

An 18-year-old woman with a history of focal epilepsy presents with increasingly frequent seizures, encephalopathy, multiple laboratory abnormalities, and hypothermia. During her hospital course, her symptoms waxed and waned. Multiple etiologies of her symptoms were considered, but the spontaneous resolution of her symptoms and an abnormal MRI of the brain revealed the final diagnosis.

Psychiatric symptoms in children with low-grade glioma and craniopharyngioma: A systematic review

The presentation of psychiatric symptoms in pediatric low-grade brain tumors is challenging because this can delay proper diagnosis and treatment. We performed a systematic review of psychiatric presenting symptoms of low-grade brain tumors in pediatric patients. We searched the PubMed and Web of Science databases of studies published in English from 1977 until 2019 reporting patients aged ≤21 years at the time of tumor diagnosis who exhibited psychiatric/behavioral symptoms before diagnosis of low-grade glioma (LGG), pilocytic astrocytoma (PA), or craniopharyngioma (CP). Our systematic search strategy coupled each tumor type with patient age and presenting symptoms by using different variations of the search terms "childhood" and "psychiatric symptoms" or "behavioral symptoms." We identified six unique articles that met our inclusion criteria in the LGG search, 27 in the PA search, and 32 in the CP search. Six patients were included in the LGG articles (age range, 3-16 years), 75 in the PA articles (age range, 0.5-21 years), and 87 in the CP articles (age range, 0.67-21 years). The most common presenting symptoms included eating disorders (n = 64) and behavioral changes (n = 49). Our findings demonstrate the need to establish clear criteria for neuroimaging indications for pediatric patients exhibiting eating disorders.

Persistent inflammation and anemia among critically ill septic patients

BACKGROUND

Associations among inflammatory cytokines, erythropoietin (EPO), and anemia in critically ill septic patients remain unclear. This study tested the hypothesis that elevated inflammatory cytokines and decreased EPO would be associated with iron-restricted anemia while accounting for operative blood loss, phlebotomy blood loss, and red blood cell (RBC) transfusion volume.

METHODS

Prospective observational cohort study of 42 critically ill septic patients was conducted. Hemoglobin (Hb) at sepsis onset and hospital discharge were used to calculate ΔHb. Operative blood loss, phlebotomy blood loss, and RBC transfusion volume were used to calculate adjusted ΔHb (AdjΔHb) assuming that 300 mL RBC is equal to 1 g/dL Hb. Patients with AdjΔHb of greater than 0 (positive AdjΔHb, n = 18) were compared with patients with AdjΔHb of less than or equal to 0 (negative AdjΔHb, n = 24).

RESULTS

Plasma tumor necrosis factor α, granulocyte colony-stimulating factor, interleukin (IL)-6, IL-8, EPO, erythrocyte mean corpuscular volume, and serum transferrin receptor were measured on days 0, 1, 4, 7, and 14. Patients with negative AdjΔHb had significantly higher day 14 levels of IL-6 (37.4 vs. 15.2 pg/mL, p < 0.05), IL-8 (39.1 vs. 18.2 pg/mL, p = 0.01), and granulocyte colony-stimulating factor (101.3 vs. 60.5 pg/mL, p = 0.01), but not EPO. On linear regression analysis, lower AdjΔHb was associated with higher day 14 levels of IL-6 (r = 0.22, p < 0.01), IL-8 (r = 0.10, p = 0.04), stromal cell-derived factor 1 (r = 0.14, p = 0.02), and tumor necrosis factor α (r = 0.13, p = 0.02), but not EPO. Patients with negative AdjΔHb had significantly lower mean corpuscular volume on days 4 (89.6 vs. 93.2 fL/cell, p = 0.04), 7 (92.3 vs. 94.9 fL/cell, p = 0.04), and 14 (92.1 vs. 96.0 fL/cell, p = 0.03) but similar serum transferrin receptor levels.

CONCLUSION

Persistent elevation of inflammatory cytokines was associated with iron-restricted anemia among critically ill septic patients, occurring in the absence of systemic iron deficiency, independent of endogenous EPO.

LEVEL OF EVIDENCE

Prognostic study, level II.

Chronic Pancytopenia due to Centrally Mediated Hypothermia in Two Children with Severe Neurological Impairment

We report on recurrent pancytopenia over five years in two children with severe impairment of the central nervous system. Assessment by hematology did not identify an etiology, including bone marrow biopsy in one. Both patients had sustained normalized blood cell counts following interventions to maintain or return to a temperature above 33 °C. Acute cytopenias following medically induced and environmental hypothermia have been reported. Recurrent pancytopenia due to centrally mediated hypothermia in patients with severe neurological impairment is often not recognized, putting such children at risk for unnecessary testing and transfusions. We provide a practical approach to management that is feasible for caregivers in the home setting with suggestions for monitoring.

Management of hypothalamic disease in patients with craniopharyngioma

Patients with craniopharyngioma experience excess morbidity and mortality when compared with the background population and with other hypopituitary patients. Large, suprasellar tumours which form micropapillae into surrounding structures can cause hypothalamic damage before any therapeutic intervention; attempted gross total resection can lead to hypothalamic obesity, sleep disorders, thirst disorders and dysregulation of temperature as well as panhypopituitarism. The management of tumour bulk and the pathophysiology of hypothalamic complications have been reviewed extensively. We present a practical, clinical approach to management of hypothalamic disease in a patient with craniopharyngioma and highlight potential targets for future pharmacological or surgical intervention.

The Promotion of Erythropoiesis via the Regulation of Reactive Oxygen Species by Lactic Acid

The simultaneous increases in blood lactic acid and erythrocytes after intense exercise could suggest a link between lactate and the erythropoiesis. However, the effects of lactic acid on erythropoiesis remain to be elucidated. Here, we utilized a mouse model to determine the role of lactic acid in this process in parallel with studies using leukaemic K562 cells. Treatment of K562 cells in vitro with lactic acid increased the mRNA and protein expression of haemoglobin genes and the frequency of GPA⁺ cells. Also, increases in haematocrit and CD71⁻/Ter119⁺ erythroid cells were observed in lactic acid-treated mice, which showed a physiological increase in blood lactate. Mouse bone marrow CD34⁺/CD117⁻ cells showed an increase in erythroid burst-forming units after stimulation with lactic acid in vitro. Furthermore, lactic acid increased the intracellular reactive oxygen species (ROS) content in bone marrow and in K562 cells. Erythroid differentiation induced in Haematopoietic Stem Cells (HSCs) and K562 cells by lactic acid was abolished by reducing ROS levels with SOD or 2-mercaptoethanol, which suggests that ROS is a critical regulator of this process. These findings provide a better understanding of the role of lactic acid in cellular metabolism and physiological functions.

Diverse of Erythropoiesis Responding to Hypoxia and Low Environmental Temperature in Vertebrates

Erythrocytes are responsible for transporting oxygen to tissue and are essential for the survival of almost all vertebrate animals. Circulating erythrocyte counts are tightly regulated and respond to erythrocyte mass and oxygen tension. Since the discovery of erythropoietin, the erythropoietic responses to environment and tissue oxygen tension have been investigated in mice and human. Moreover, it has recently become increasingly clear that various environmental stresses could induce the erythropoiesis via various modulating systems, while all vertebrates live in various environments and habitually adapt to environmental stress. Therefore, it is considered that investigations of erythropoiesis in vertebrates provide a lead to the various erythropoietic responses to environmental stress. This paper comparatively introduces the present understanding of erythropoiesis in vertebrates. Indeed, there is a wide range of variations in vertebrates' erythropoiesis. This paper also focused on erythropoietic responses to environmental stress, hypoxia, and lowered temperature in vertebrates.

Hepatic confinement of newly produced erythrocytes caused by low-temperature exposure in Xenopus laevis

Diminished erythrocyte count and erythropoiesis have been reported during hypothermia in some ectothermic animals. In this study, the African clawed frog, Xenopus laevis, was used to investigate the cause of hypothermia-induced anemia. We developed a new model of hypothermia at 5°C and monitored blood cell count and erythropoiesis on several days. Erythrocyte count declined by 30% on the first day following cold exposure (5°C) and mRNA expression of hemeoxygenase-1 was enhanced 10-fold; accumulation of iron as a result of heme degradation was observed in the liver. One day after low-temperature exposure, erythropoietin mRNA expression was elevated in the liver and lung compared with that at normal temperature (22°C) by qRT-PCR analysis. Examination of liver sections (i.e. the erythropoietic organ) showed an increase in o-dianisidine-positive erythrocytes in the hepatic sinusoid 5 days after the onset of low-temperature exposure compared with normal liver. Peripheral erythrocyte count remained low, indicating that newly produced erythrocytes did not migrate from the liver to the circulation during hypothermia. In conclusion, this study reveals hypothermic anemia as being associated with hepatic erythrocyte destruction; prolonged anemia during low-temperature exposure is concomitant with newly produced erythrocytes being confined to the liver and may lead to new insights into vertebrate hematopoiesis.

Central hypothermia as a cause of acute pancreatitis in children with neurodevelopmental impairment

Children with severe neurodevelopmental impairment are at risk for recurrent hypothermia, defined as a temperature of less than 35 degrees C, as a result of hypothalamic dysfunction. Acute pancreatitis following hypothermia from environmental exposure or induced as medical therapy has been reported in adults. In this case series of 10 children (six males, four females) with severe neurodevelopmental impairment and associated hypothermia, five had an episode of acute pancreatitis. These five patients had documented hypothermia, an elevated lipase of greater than 1000U/L, and presenting symptoms of irritability or lethargy along with gastrointestinal symptoms such as feeding intolerance. Four of these five children had no other explanation for pancreatitis; the fifth had multiple gallstones. This case series identifies the risk of acute pancreatitis in children with central hypothermia. Monitoring for resolution upon establishment of euthermia can minimize unnecessary testing and cost.