Severe Hyperkalemia Immediately After Birth.

BACKGROUND Hyperkalemia is an important cause of arrhythmias and a medical emergency that requires urgent treatment. The etiology is usually multifactorial. It is most frequently caused by impaired potassium secretion, followed by transcellular potassium shifts and an increased potassium load. CASE REPORT A male newborn developed monomorphic ventricular tachycardia 2 hours after birth. He was born in the 35th week of gestation by urgent C-section following placental abruption. Laboratory results showed hemolytic anemia (Hb 99 g/L, Hct 0.31) with increased bilirubin levels and reticulocytosis, thrombocytopenia (39×109/L), hypoglycemia (0.8 mmol/L), and severe hyperkalemia (9.8 mmol/L). Umbilical artery blood gas analysis showed hypoxemia with acidosis (pO2 3.8 kPa, pH 7.21, pCO2 7.84 kPa, HCO3 23.3 mmol/L, BE -5 mmol/L). Creatinine (102 µmol/L) and urea (9.8 mmol/L) were mildly elevated. Inflammatory markers were also increased (CRP 26 mg/L, blood leukocyte count 24×109/L). Early-onset sepsis, caused by Candida albicans, was confirmed approximately 24 hours after birth. Non-invasive ventilation with 35-40% O2 was necessary due to transient tachypnea. The neonate received a transfusion of packed red blood cells, a 10% glucose infusion, and empirical antibiotic therapy. Hyperkalemia accompanied by arrhythmias was treated with calcium gluconate, insulin, Sorbisterit enema, and, finally, by exchange transfusion. CONCLUSIONS We report a case of severe hyperkalemia in a newborn immediately after birth. Making a decision as early as possible regarding exchange transfusion is essential in patients with hyperkalemia with electrocardiogram changes and hemodynamic instability.

Phenylhydrazine administration accelerates the development of experimental cerebral malaria.

Phenylhydrazine (PHZ) treatment is generally used to enhance parasitemia in infected mice models. Transient reticulocytosis is commonly observed in iron-deficient anemic hosts after treatment with iron supplementation, and is also associated with short-term hemolysis caused by PHZ treatment. In this study, we investigated the relationship between reticulocytosis and cerebral malaria (CM) in a murine model induced by PHZ administration before Plasmodium berghei ANKA (PbA) infection. Mortality and parasitemia were checked daily. Pro-inflammatory cytokines and IL-10 were quantified by ELISA. The expression of CXCL9, CXCL10, CCL5, and CXCR3 mRNAs was determined by real-time PCR. Brain sequestration of CD4(+) and CD8(+) T cells and populations of splenic Th1 CD4(+) T cells, dendritic cells (DCs), CD11b(+) Gr1(+) cells, and regulatory T cells (Tregs) were assessed by FACS. PHZ administration dramatically increased parasitemia from day 3 to day 5 post infection (p.i.) compared with the untreated control infected mice group; also, CM developed at day 5 p.i., compared with day 7 p.i. in untreated control infected mice, as well as significantly decreased blood-brain barrier function (P < 0.001). PHZ administration during PbA infection significantly increased the expression of CXCL9 (P <0.05) and VCAM-1 (P <0.001) in the brain, increased the expression of CXCL10, CCL5 and CXCR3, and significantly increased the recruitment of CD4(+) and CD8(+) T cells (P <0.001 and P <0.01, respectively) as well as CD11b(+) Gr1(+) cells to the brain. In addition, PHZ administration significantly increased the numbers of IL-12-secreting DCs at days 3 and 5 p.i. compared to those of untreated control infected mice (P <0.001 and P <0.01, respectively). Consequently, the activation of CD4(+) T cells, especially the expansion of the Th1 subset (P <0.05), was significantly and dramatically enhanced and was accompanied by marked increases in the production of protein and/or mRNA of the Th1-type pro-inflammatory mediators, IFN-γ and TNF-α (P <0.01 for both for protein; P <0.05 for TNF-α mRNA). Our results suggest that, compared to healthy individuals, people suffering from reticulocytosis may be more susceptible to severe malaria infection in malaria endemic areas. This has implications for the most appropriate selection of treatment, which may also cause reticulocytosis in patients living in such areas.

Efficacy of green tea extract in two exercise models.

Oral administration of green tea extract in a dose of 6 mg/kg twice a day (before and after exercise) over 2 weeks significantly increased swimming times on week 1 and 2 in comparison with control animals receiving water. The 7-day and final exhaustive running in rats was accompanied by a significant decrease in spleen weight and iron serum levels associated with developed reticulocytosis. Administration of green tea extract in a dose of 12 mg/kg once a day (before exercise) for 2 weeks did not affect the duration of the running, but prevented the decrease in serum iron and spleen weight, that, along with a significantly increased concentration of reduced glutathione in erythrocytes, can indicate a normalizing effect of green tea extract on hemopoiesis and stimulating effect on the antioxidant system of erythrocytes.

Reticulocytosis in nonanemic dogs: increasing prevalence and potential etiologies.

BACKGROUND: An increasing prevalence of reticulocytosis in the absence of anemia (RAA) in dogs has been suspected in recent years. OBJECTIVES: The objectives were to determine whether prevalence of RAA in our canine population has been increasing over the last years, and to identify potential predisposing factors. METHODS: The annual prevalence of RAA in adult dogs was determined between 2000 and 2012. Clinical histories and CBC data were analyzed for all dogs, as well as owner response to a questionnaire including information on nutrition and supplements was conducted for dogs with RAA identified between 2011 and 2012. In addition, serum iron concentration (Fe), total iron-binding capacity (TIBC), and percent transferrin saturation (%TS) were determined in 14 dogs with RAA and compared with 8 healthy control dogs. RESULTS: Reticulocytosis in the absence of anemia was identified in 1035 dogs, with the prevalence increasing since 2006. Dogs with RAA evaluated after 2006 (n = 853) had significantly lower MCV and were more likely to have microcytosis than those prior to 2006 (n = 182). Increased incidence of osteoarthritis was observed in dogs evaluated after 2006, including the dogs studied between 2011 and 2012 (n = 31), and administration of nonsteroidal anti-inflammatory drugs, omega-3 fatty acids, and glucosamine was more common in the latter. Significantly lower mean Fe and %TS, and higher TIBC were found in dogs with RAA compared to unaffected dogs. CONCLUSIONS: Prevalence of RAA has increased in recent years in our canine population. More ubiquitous use of anti-inflammatory medications and nutraceuticals, associated with increased diagnosis of osteoarthritis should be considered as contributing factors.

Duffy antigen expression on reticulocytes does not alter following blood loss in an autologous donation model.

BACKGROUND: The Duffy blood group (Fy) antigen functions as the receptor whereby the malarial parasite Plasmodium vivax invades reticulocytes. In this study, we evaluated an autologous blood donation model to measure Fy expression during the anticipated response to blood loss. AIMS: This study aims to examine Fy expression following anticipated reticulocytosis in response to blood loss from autologous whole blood donation. METHOD: Subjects were healthy blood donors presenting for planned collection of two or three autologous units. Whole blood (450 ml +/- 10%) was collected and processed. Blood samples for Fy testing were obtained from the donations. These were assayed by flow cytometry by measuring binding of a phycoerythrin-labelled anti-Fy6 antibody and compared against reticulocyte numbers. Reticulocyte numbers were measured using thiazole orange. Results were compared from baseline (first donation) with samples at second and, if available, third, donations. Phenotyping for Fy a and b antigens was performed. RESULTS: Reticulocytes increased by a mean of 37% over baseline [0.93% (range 0.31-1.93) to 1.23% (0.32-3.51%)] following donation of two (n = 32) or three (n = 9) autologous whole blood units. Absolute reticulocyte count remained low. Mean and median Fy expression on mature red blood cells and reticulocytes did not change from baseline levels despite individual variation. No apparent relationship to serologically determined Fy a and/or b antigen status was present. CONCLUSION: Baseline expression of Fy antigen on mature red blood cells and reticulocytes is quite variable between individuals, but appears not to be greatly affected by mild to moderate reticulocytosis following blood loss in an autologous blood donation model.