Audit of nutrition support for hematopoietic stem cell transplantation at a single institution

OBJECTIVE: To analyze experience with total parenteral nutrition (TPN) for hematopoietic stem cell transplantation (HSCT) at our institution compared with reports in the literature. PATIENTS AND METHODS: We reviewed medical records of 100 patients (53 men and 47 women) who underwent HSCT from 1992 to 2001. Data were abstracted on demographics, primary diagnosis, type of transplantation, myeloablative regimen, length of hospital stay, time to engraftment, 1- and 5-year survival, initiation and duration of TPN, and TPN-related complications. RESULTS: Seventy-one transplantations were autologous, 27 allogeneic, and 2 syngeneic. The median age of the patients was 51 years (range, 19-71 years). We initiated TPN when patients' oral caloric intake was less than 50% of their estimated needs (4 to 7 days after the start of myeloablative therapy; median, 1.2 days after HSCT; range, 8 days before HSCT to 13 days after HSCT). We discontinued TPN when oral intake was more than 50% of estimated needs (median duration, 16 days for autologous and 24 days for allogeneic transplantations, with the shortest duration in breast cancer patients and the longest duration in those treated with cyclophosphamide). Mean weight loss was less than 2%. No differences in patient characteristics, myeloablative regimen, or diagnosis were observed between patients who required and those who did not require TPN. Infection, hospital stay, time to engraftment, and mortality were comparable to published reports. CONCLUSION: In patients undergoing HSCT, TPN should not be initiated until oral caloric intake is less than 50% of estimated needs. During the period of inadequate oral intake, TPN maintains stable body weight with longer duration of support needed for patients undergoing allogeneic than for those undergoing autologous transplantations.     

Comparing bacterial genomes through conservation profiles

We constructed two-dimensional representations of profiles of gene conservation across different genomes using the genome of Escherichia coli as a model. These profiles permit both the visualization at the genome level of different traits in the organism studied and, at the same time, reveal features related to the genomes analyzed (such as defective genomes or genomes that lack a particular system). Conserved genes are not uniformly distributed along the E. coli genome but tend to cluster together. The study of gene distribution patterns across genomes is important for the understanding of how sets of genes seem to be dependent on each other, probably having some functional link. This provides additional evidence that can be used for the elucidation of the function of unannotated genes. Clustering these patterns produces families of genes which can be arranged in a hierarchy of closeness. In this way, functions can be defined at different levels of generality depending on the level of the hierarchy that is studied. The combined study of conservation and phenotypic traits opens up the possibility of defining phenotype/genotype associations, and ultimately inferring the gene or genes responsible for a particular trait.     

Interpopulation variability among Panstrongylus megistus (Hemiptera: Reduviidae) from Brazil

Comparisons were made among Panstrongylus megistus (Burmeister) from three areas of Brazil (Bahia, Minas Gerais, and Santa Catarina), where populations differ with regard to their degree of association with human dwellings. The following characters were studied: morphology of the eggs and the male genitalia; morphometry of the head and thorax; isoenzyme profile; enzymatic activity of the alpha-glycerophosphate dehydrogenase (alpha-GPDH); and cytogenetics. In general, differences were observed in the weight, diameter, and length of the egg among Bahia, Minas Gerais, and Santa Catarina populations. Differences were not observed in the architecture of the egg exochorion. The size of the median process of the pygophore of the male genitalia of individuals from Bahia differed from the other two populations. The Minas Gerais population presented the largest number of denticles in the endosome process. The morphometry of the head and thorax differentiated Santa Catarina from the Bahia and Minas Gerais populations. Phosphoglucomutase (EC 5.4.2.2., PGM) was the only enzyme out of 11 that showed polymorphism; the population from Minas Gerais was most polymorphic, whereas the population from Santa Catarina was monomorphic. Study of the alpha-GPDH activity and cytogenetics did not reveal differences among the three populations. Analysis of all the characters studied together with information on these three populations from previous publications allowed a phenogram to be constructed. Two distinct groups were evident, one represented by Santa Catarina and the other by Bahia and Minas Gerais. Considering the greater variability of the Minas Gerais and Bahia populations, we propose the inclusion of these states within the area of origin of P. megistus.     

Forced oscillation technique in the detection of smoking-induced respiratory alterations: diagnostic accuracy and comparison with spirometry

INTRODUCTION:

Detection of smoking effects is of utmost importance in the prevention of cigarette‐induced chronic airway obstruction. The forced oscillation technique offers a simple and detailed approach to investigate the mechanical properties of the respiratory system. However, there have been no data concerning the use of the forced oscillation technique to evaluate respiratory mechanics in groups with different degrees of tobacco consumption.

OBJECTIVES:

(1) to evaluate the ability of the forced oscillation technique to detect smoking‐induced respiratory alterations, with special emphasis on early alterations; and (2) to compare the diagnostic accuracy of the forced oscillation technique and spirometric parameters.

METHODS:

One hundred and seventy subjects were divided into five groups according to the number of pack–years smoked: four groups of smokers classified as <20, 20–39, 40–59, and >60 pack–years and a control group. The four groups of smokers were compared with the control group using receiver operating characteristic (ROC) curves.

RESULTS:

The early adverse effects of smoking in the group with <20 pack–years were adequately detected by forced oscillation technique parameters. In this group, the comparisons of the ROC curves showed significantly better diagnostic accuracy (p<0.01) for forced oscillation technique parameters. On the other hand, in groups of 20–39, 40–59, and >60 pack–years, the diagnostic performance of the forced oscillation technique was similar to that observed with spirometry.

CONCLUSIONS:

This study revealed that forced oscillation technique parameters were able to detect early smoking‐induced respiratory involvement when pathologic changes are still potentially reversible. These findings support the use of the forced oscillation technique as a versatile clinical diagnostic tool in helping with chronic obstructive lung disease prevention, diagnosis, and treatment.     

Outbreak of carbapenem-resistant Acinetobacter baumannii producing the OXA-23 enzyme in Curitiba,Brazil

Carbapenem-resistant Acinetobacter baumannii isolates were obtained from eight patients in two hospitals in Curitiba, Brazil. The isolates were multiresistant, belonged to a single strain, and produced the OXA-23 carbapenemase. Treatment options were limited, although the isolates were susceptible to polymyxin B in vitro. The strain contributed to the deaths of five patients.     

Histopathology of gastritis in Helicobacter pylori-infected children from populations at high and low gastric cancer risk

Infection with Helicobacter pylori has been recognized as a cause of gastric carcinoma. Although the neoplasia is always detected in adults, the infection starts in childhood. It has been reported that early age at first infection is a determinant of gastric cancer risk. In this study, we examined the histopathology of the gastric mucosa in infected children from a population at high risk for gastric cancer (Pasto, Colombia) and compared it with that of a lower-risk population (New Orleans, LA). Gastric biopsies obtained from antrum and corpus were stained with hematoxylin and eosin and Steiner's silver method. Immunohistochemical stains were used to identify B lymphocytes (CD20), T lymphocytes (CD3 and CD8), macrophages (CD68), and polymorphonuclear neutrophil myeloperoxidase. Morphometric techniques were used to evaluate the immunohistochemical stains. In both populations, the inflammatory lesions were seen predominantly in the antrum. Compared with children from the lower-risk populations, children from the higher-risk population exhibited more severe polymorphonuclear neutrophil infiltration, stromal and intraepithelial lymphocyte infiltration, mucus depletion, and H. pylori colonization density. Regenerative activity was significantly more marked in the lower-risk population. Morphometric analysis of immunohistochemical stains showed increased representation of T lymphocytes and macrophages in the higher-risk population. Most T lymphocytes stained positive for CD8, a marker of suppressor/cytotoxic cells. B lymphocytes were relatively more abundant in the lower-risk population. The possibility that the aforementioned characteristics of H. pylori infection in children are related to cancer risk in adults is discussed.     

EAACI Guidelines on allergen immunotherapy: IgE‐mediated food allergy

Food allergy can result in considerable morbidity, impairment of quality of life, and healthcare expenditure. There is therefore interest in novel strategies for its treatment, particularly food allergen immunotherapy (FA‐AIT) through the oral (OIT), sublingual (SLIT), or epicutaneous (EPIT) routes. This Guideline, prepared by the European Academy of Allergy and Clinical Immunology (EAACI) Task Force on Allergen Immunotherapy for IgE‐mediated Food Allergy, aims to provide evidence‐based recommendations for active treatment of IgE‐mediated food allergy with FA‐AIT. Immunotherapy relies on the delivery of gradually increasing doses of specific allergen to increase the threshold of reaction while on therapy (also known as desensitization) and ultimately to achieve post‐discontinuation effectiveness (also known as tolerance or sustained unresponsiveness). Oral FA‐AIT has most frequently been assessed: here, the allergen is either immediately swallowed (OIT) or held under the tongue for a period of time (SLIT). Overall, trials have found substantial benefit for patients undergoing either OIT or SLIT with respect to efficacy during treatment, particularly for cow's milk, hen's egg, and peanut allergies. A benefit post‐discontinuation is also suggested, but not confirmed. Adverse events during FA‐AIT have been frequently reported, but few subjects discontinue FA‐AIT as a result of these. Taking into account the current evidence, FA‐AIT should only be performed in research centers or in clinical centers with an extensive experience in FA‐AIT. Patients and their families should be provided with information about the use of FA‐AIT for IgE‐mediated food allergy to allow them to make an informed decision about the therapy.     

Clinical trials in allergen immunotherapy: current concepts and future needs

Allergen immunotherapy (AIT) is a safe, effective treatment for allergic rhinoconjunctivitis and allergic asthma. However, AIT's clinical effect is still contested—primarily due to heterogeneity in clinical trial designs, study populations, therapeutic formulations, and efficacy criteria. After discussing current concepts and unmet needs, an international panel of experts made several recommendations: (i) explore and validate definitions for (clinical) responders in AIT trials; (ii) use of well‐documented, standardized provocation tests prior to inclusion of subjects with relevant diseases in AIT trials; (iii) monitoring neo‐sensitizations and occurrence of new allergy in extended AIT trials, and exclusion of polyallergic participants; (iv) validation of allergen exposure chambers with regard to natural exposure; (v) in studies of seasonal allergies, focus on peak exposure but also consider organizing two parallel, geographically distinct but otherwise identical trials; (vi) discuss adaptive trial designs with the regulatory authorities; (vii) use e‐health and m‐health technologies to capture more information on individual exposure to allergens; (viii) initiate research on potential psychological, biochemical, immune, neural, and even genomic markers of the placebo response; (ix) identify trial designs and primary endpoints that will give children with allergies easier, faster access to AIT formulations; and (x) promote and apply standardized methods for reporting systemic and local adverse events. The latest technologies and trial designs may provide novel, ethical ways of reducing bias and heterogeneity in AIT clinical trials. There is scope for physicians, patient organizations, companies, and regulators to improve clinical trials in AIT and, ultimately, to provide patients with better treatments.     

Possible Allergenic Role of Tropomyosin in Patients with Adverse Reactions after Fish Intake

In a recent case report, patient’s anti-fish tropomyosin IgE was associated with gastrointestinal symptoms. We aimed to demonstrate on a wider scale that the panallergen tropomyosin should not be limited to invertebrate species and that clinically relevant reactions could be elicited by vertebrate tropomyosin. On the whole, 19 patients with adverse reactions after fish intake and showing negative skin tests with commercial fish extracts were included. Fish tropomyosin was recognized by 10/19 patients’ IgE by immunoblotting. All patients with gastrointestinal complaints after fish intake (6/6) showed an IgE band matching with tropomyosin. Cod, albacore, and swordfish tropomyosins were recognized by most patients although 3/10 patients did not claim adverse reactions to these fish species. Immunoblotting with a battery of antigens from different fish species have a high yield of positivity at a band matching with tropomyosin molecular weight, even if they have not been claimed to be causative agents of symptoms. Tropomyosin is therefore a good candidate to be investigated as a clinically relevant fish allergen in patients who report adverse reactions after fish intake.     

Taking the lymphatic route: dendritic cell migration to draining lymph nodes

In contrast to leukocyte migration through blood vessels, trafficking via lymphatic vessels (LVs) is much less well characterized. An important cell type migrating via this route is antigen-presenting dendritic cells (DCs), which are key for the induction of protective immunity as well as for the maintenance of immunological tolerance. In this review, we will summarize and discuss current knowledge of the cellular and molecular events that control DC migration from the skin towards, into, and within LVs, followed by DC arrival and migration in draining lymph nodes. Finally, we will discuss potential strategies to therapeutically target this migratory step to modulate immune responses.