Anemia of chronic disease (ACD) is frequently found in patients with chronic immune activation. Since most studies on ACD pathophysiology were performed with cell culture or animal models but not in humans, we examined 37 ACD patients suffering from autoimmune diseases or infections, 10 subjects with irondeficiency anemia (IDA), 10 anemic patients with hereditary spherocytosis (HS), and 27 age-matched controls. Although hemoglobin concentrations were comparable between ACD and IDA patients, the latter presented with significantly higher serum erythropoietin concentrations than ACD patients. The significant negative correlation between erythropoietin and hemoglobin levels observed in IDA patients was also found in a group of anemic but not hypoferremic hereditary spherocytosis subjects, but not in ACD patients. Increased serum concentrations of the hepcidin precursor prohepcidin were paralleled by a decreased expression of the iron exporter ferroportin in circulating monocytes of ACD patients. IntroductionAnemia of chronic disease (ACD), also termed as anemia of inflammation, is likewise the most frequent anemia in hospitalized patients. This mild to moderate normocytic to microcytic anemia is found with a frequency between 8% and 95% in patients suffering from diseases that are associated with chronic immune activation, such as autoimmune disorders including rheumatoid arthritis and malignancies and chronic infections including HIV. [1][2][3] At least 3 major immunity-driven mechanisms contribute to the development of ACD. These include the development of hypoferremia with subsequent limitation of iron availability for erythroid progenitor cells, antiproliferative effects of cytokines toward the proliferation and differentiation of erythroid progenitor cells, and, last but not least, an impaired production and reduced biologic activity of erythropoietin (Epo).The development of hypoferremia results from a complex interaction of acute-phase proteins and cytokines together with an anticipated reduction in the lifespan of erythrocytes. Thereby, the absorption of iron from the gut is reduced while iron acquisition and retention by cells of the reticulo-endothelial system (RES) is greatly stimulated, leading to the development of iron-restricted erythropoiesis and anemia. The liver-derived acute-phase protein hepcidin plays a central role in this setting, since it reduces both duodenal iron absorption and iron export from monocytes/ macrophages. [4][5][6] These effects can be referred to as interaction of hepcidin with the transmembrane protein ferroportin, 7 which is responsible for the transfer of iron from enterocytes and monocytes/ macrophages to the circulation. 8,9 The expression of hepcidin by hepatocytes is induced by lipopolysaccharide (LPS) and interleukin-6 (IL-6), resulting in the development of hypoferremia in mice within a few hours after injection. 6,10 Moreover, proinflammatory and anti-inflammatory cytokines play an important role in the pathophysiology of ACD by increasing iron accumulation and sto...
BackgroundHereditary spherocytosis is a very heterogeneous form of hemolytic anemia. The aim of this study was to relate the type of molecular defect with clinical and hematologic features and response to splenectomy using information from a large database of patients.
Summary The clinical course of thrombotic thrombocytopenic purpura (TTP) is characterized by recurrent disease episodes in up to 50% of cases. The clinical presentation and severity of different TTP episodes have not been systematically compared. Laboratory and clinical information from 51 patients with recurrent disease, derived from 136 patients with TTP included in the Milan TTP registry (URL: http://www.ttpdatabase.org), were used to compare mortality, symptoms and disease‐related laboratory measurements in different disease episodes. The prevalence of severe neurological symptoms (coma, seizures, and focal neurological defects) was significantly lower in recurrences than in the first episode. Platelet counts and haemoglobin levels at presentation were higher in recurrences than in the first disease episode, and lactate dehydrogenase levels were lower. Also, mortality tended to be lower in the second and third disease episodes than in the first. Recurrences of TTP are generally milder than first episodes. These differences in severity should be taken into account in clinical research on TTP and in patient management.
Red cell (RBC) deformability and membrane-bound immunoglobulin G (IgG) were studied to better understand premature clearance of erythrocytes in hereditary spherocytosis. Averaged deformability profiles from cells having comparable cell age revealed that splenectomy was more beneficial for spectrin/ankyrin-deficient than for band 3–deficient RBCs. Splenectomy prevented an early loss of young cells in both types of deficiencies. It had an additional beneficial effect on spectrin/ankyrin-deficient but not band 3–deficient RBCs. It prolonged the survival of mature spectrin/ankyrin-deficient RBCs such that they lost their deformability more slowly than RBCs from patients who had not undergone splenectomy. Band 3–deficient RBCs lost their deformability at the same rate before and after splenectomy. In HS patients with band 3 deficiency who underwent splenectomy, RBC deformability inversely correlated with the number of RBC-bound IgG (up to 140 molecules per cell). In spectrin/ankyrin deficiency, RBC-bound IgG remained at control levels (60 IgG or less per cell). It appears that spectrin/ankyrin-deficient RBCs escaped opsonization by releasing band 3–containing vesicles because their band 3 content and deformability dropped in parallel with increasing cell age. Band 3–deficient RBCs did not lose band 3 with increasing cell age. Hence, it is possible that band 3 clusters required for bivalent binding of low-affinity–IgG, naturally occurring antibodies were retained in band 3–deficient RBCs with a relative excess of skeletal proteins but were released from spectrin/ankyrin-deficient RBCs, in which vesicle budding was facilitated by an impaired skeleton.
A new test for the laboratory diagnosis of spherocytosis, conventionally called ‘Pink test’, is presented. This test, semi-quantitatively or quantitatively, determines the hemolysis of small blood samples in a solution containing glycerol (135 mmol/l), NaCl (25 mmol/l), NaN3 (1.5 mmol/l), buffered to pH 6.66 with Bis-Tris (70 mmol/l) and HC1. ‘Pink test’, as well as ‘acidified’ glycerol lysis test, were positive in 100% of 42 patients suffering from hereditary spherocytosis, and optimally discriminated them from healthy subjects, showing a diagnostic sensitivity greater than ‘standard’ glycerol lysis test and osmotic fragility in hypotonic saline solutions of fresh or incubated blood. ‘Pink test’ was also positive in some cases of renal failure, immunohemolytic anemia, chronic hemoproliferative disorders, normal pregnant women, and negative in other microcytic anemias (beta-thalassemia, iron deficiency anemia). The results do not critically depend on pH of the solution (differently from those obtained with ‘acidified’ glycerol lysis test), and for this reason they show a good reproducibility.
Background Benign acute childhood myositis (BACM) is a self-limited syndrome associated with viral infections characterized by symmetric lower extremity pain typically affecting school-aged children. Evolution in rhabdomyolysis and kidney damage is rarely reported. Despite this, the acute presentation commonly concerns both parents and health care providers, often leading to unnecessary workup. The aim of the study was to determine the features and outcome of a large series of children with BACM identifying a management pathway for pediatricians in Emergency Department (ED). Methods We conducted a retrospective study of patients with BACM managed in 2 Italian pediatric ED during a period of 8 and a half years. Demographic data, clinical, and laboratory results were extracted from electronic medical records. Recurrence, complications, treatments, and outcomes were also recorded. Descriptive statistics were produced for first-episode patients and for those with recurrence of myositis. A comparison between groups was performed. Results One hundred and thirteen patients with BACM were identified. Ninety-two children (65 males) had a single episode, while ten (nine males) had recurrence. The mean age at presentation was 6.0 years (range 2–13,2). All patients had normal neurological examination and no one developed myoglobinuria, or renal failure. At first evaluation median CK level was 1413 UI/l (normal values < 150 U/L). Median CK of “recurrent” patients was higher than “non-recurrent” (2330 vs 1150 U/L, p = 0.009). Viral studies were positive in 51/74 cases, with high prevalence of Influenza viruses. Ninety-six patients (85%) were hospitalized with a median of 4 days. No patients had any residual muscular impairment. Conclusions BACM has an excellent prognosis. Severe pathological conditions can be excluded with a complete history and clinical examination and simple blood and urine tests, avoiding unnecessary diagnostic investigations. Most patients may be discharged home from ED recommending hydration, rest, analgesics and careful follow-up.
The gastrointestinal tract is colonized with a highly different population of bacterial, viral, ad fungal species; viruses are reported to be dominant. The composition of gut virome is closely related to dietary habits and surrounding environment. Host and their intestinal microbes live in a dynamic equilibrium and viruses stimulate a low degree of immune responses without causing symptoms (host tolerance). However, intestinal phages could lead to a rupture of eubiosis and may contribute to the shift from health to disease in humans and animals. Viral nucleic acids and other products of lysis of bacteria serve as pathogen-associated molecular patterns (PAMPs) and could trigger specific inflammatory modulations. At the same time, phages could elicit innate antiviral immune responses. Toll-like receptors (TLRs) operated as innate antiviral immune sensors and their activation triggers signaling cascades that lead to inflammatory response. J. Med. Virol. 88:1467-1472, 2016. © 2016 Wiley Periodicals, Inc.
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