Combination of ABO blood group incompatibility and glucose-6-phosphate dehydrogenase deficiency: effect on hemolysis and neonatal hyperbilirubinemia

The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia.     

Pulmonary contusions in patients with rib fractures: The need to better classify a common injury

BackgroundPulmonary contusions are common injuries. Computed tomography reveals vast contused lung volume spectrum, yet pulmonary contusions are defined dichotomously (unilateral vs bilateral). We assessed whether there is stepwise increased risk of pulmonary complications among patients without, with unilateral, and with bilateral pulmonary contusion.MethodsWe identified adults admitted with rib fractures using the largest US inpatient database. After propensity-score-matching patients without vs with unilateral vs bilateral pulmonary contusions and adjusting for residual confounders, we compared risk for pneumonia, ventilator-associated pneumonia (VAP), respiratory failure, intubation, and mortality.ResultsAmong 148,140 encounters of adults with multiple rib fractures, 19% had concomitant pulmonary contusions. Matched patients with pulmonary contusions had increased risk of pneumonia 19% [95%CI:16–33%], respiratory failure 40% [95%CI: 31–50%], and intubation 46% [95%CI: 33–61%]. Delineation showed bilateral contusions, not unilateral contusions, attributed to increased risk of complications.ConclusionsThere is likely a correlation between contused lung volume and risk of pulmonary complications; dichotomously classifying pulmonary contusions is insufficient. Better understanding this correlation requires establishing the clinically significant contusion volume and a correspondingly refined classification system.     

Features of structural brain abnormality detected in first-episode psychosis

OBJECTIVE: Structural magnetic resonance imaging (MRI) studies that focus on first-episode psychosis avoid some common confounds, such as chronicity of illness, treatment effects, and long-term substance abuse. However, such studies may select subjects with poor short-term treatment response or outcome. In this study, the authors focus on structural brain abnormalities in never or minimally treated patients who underwent MRI scanning early in their first episode of psychosis. METHOD: The authors examined 37 patients (13 medication naive, 24 previously treated) who were experiencing their first episode of psychosis; the mean duration of symptoms was short (31 weeks). These patients were comparable in age, gender, handedness, ethnicity, and parental socioeconomic status to a group of 25 healthy comparison subjects. A three-dimensional, inversion recovery prepared, fast spoiled gradient/recall in the steady state scan of the whole brain that used 1.5-mm contiguous sections was performed to acquire a T(1)-weighted data set. Human ratings of volumetric measurement of brain structures were performed with stereological techniques on three-dimensional reconstructed MRIs. RESULTS: The patient group had significant deficits in cortical gray matter, temporal lobe gray matter, and whole brain volume as well as significant enlargement of the lateral and third ventricles. Structural deviations were found in both treatment-naive and minimally treated subjects. No relationships were found between any brain matter volumes and positive or negative symptoms. CONCLUSIONS: Structural brain abnormalities were distributed throughout the cortex with particular decrement evident in gray matter. This feature is consistent with altered cell structure and disturbed neuronal connectivity, which accounts for the functional abnormality of psychosis.     

Le traitement familial des enfants et des adolescents anorexiques : Des lignes directrices pour le m��decin communautaire

Anorexia nervosa (AN) is a serious life-threatening illness that typically has its onset during the adolescent years. Evidence regarding the optimal treatment of AN in children and teenagers is growing; however, much remains unknown. Although current treatment approaches vary in Canada and elsewhere, the evidence to date indicates that family-based treatment (FBT) is the most effective treatment for children and teenagers with AN. A key component of the FBT model is that the parents are given the responsibility to return their child to physical health and ensure full weight restoration. An understanding of the basic principles and philosophy underlying FBT allows the physician to initiate elements of this evidence-based intervention to young patients with AN and their families.     

Role of extracellular adenosine triphosphate in the cytotoxic T- lymphocyte-mediated lysis of antigen presenting cells

The lysis of antigen presenting cells (APCs) by cytotoxic T lymphocytes (CTLs) may be one mechanism whereby an immune response is downregulated by Staphylococcus superantigens. Disappearance of monocytes/macrophages from staphylococcal enterotoxin A (SEA)-activated peripheral blood mononuclear cell (PBMC) cultures, but not from control PBMC cultures was seen by flow cytometry. Recently, adenosine triphosphate (ATP) has been described as an effector molecule in CTL-mediated lysis of some murine tumor target cells. We have also shown that ATP caused the lysis of human macrophages, and that treatment of cells with interferon gamma (IFN gamma) rendered macrophages significantly more sensitive to ATP than untreated cells. To show that this purine nucleotide may play a role in modulating the immune system, we generated human CTLs that were stimulated with SEA, and used them as effector cells against SEA-pulsed autologous macrophages. CTLs were found to specifically lyse SEA-pulsed macrophages, while control, unpulsed, macrophages were unaffected. The addition of hexokinase, an enzyme that hydrolyzes ATP, significantly abrogated the killing of SEA-pulsed cells during the assay. In examining the mechanism of cytotoxicity, electron microscopy showed that macrophages incubated with both ATP and CTLs underwent necrosis, rather than apoptosis. From these results, it is suggested that ATP is released from CTLs during antigen presentation, and that IFN gamma- activated macrophages, which are inherently more sensitive to this mediator, are readily lysed and therefore removed from circulation, thus downregulating an immune response.