Anti-i causing acute hemolysis following a negative immediate-spin crossmatch

A unique case of acute hemolysis following transfusion of red cells (RBCs) that were found compatible by immediate-spin (IS) crossmatch technique is reported. Screening tests for unexpected antibodies, using low-ionic-strength saline (LISS), 10 minutes' incubation at 37 degrees C, and anti-IgG, were nonreactive; however, 1 transfused unit was found crossmatch incompatible by indirect antiglobulin technique (IAT). An anti-i (titer 512 at 4 degrees C) that was not an autoantibody was identified in the patient's serum. Unlike the incriminated donor RBCs, most I+ RBCs did not react by LISS-IAT. Variable reactivity was seen with ficin-treated I+ RBCs, and there was marked hemolysis of iadult and icord RBCs. In marked contrast, dominant Lu(a-b-) RBCs, with reduced expression of i, did not react by any test method; nor did autologous I+, Lu(b+) RBCs. The in vivo clinical significance of this anti-i was confirmed by monocyte monolayer assay and RBC survival studies. The patient's i antigen may have been altered, by either chemotherapy or disease, and lacked part of the i antigen-mosaic. Her antibody was directed at epitopes of i that were absent from her RBCs. Those i epitopes missing from her RBCs are also absent on dominant Lu(a-b-) RBCs. This anti-i represents a unique cause of an acute hemolytic transfusion reaction. It also represents a case of acute immune-mediated hemolysis following transfusion of IS crossmatch-compatible blood when screening tests for unexpected antibodies are nonreactive. Because of the rarity of such cases (less than 1/200,000 RBC units transfused), modifications to pretransfusion testing protocols are not proposed.     

Prevalence of Helicobacter pylori infection in Polish shepherds and their families

BACKGROUND: Helicobacter pylori infection might, in some instances, be considered as zoonosis. AIM: The aim of this study was to assess the H. pylori prevalence in Polish shepherds and in their families as compared to controls. Patients and methods. A total of 42 shepherds from Polish Tatra Mountains with regular contact with sheep, 28 members of their families with incidental contacts and 61 age- and gender-matched farmer controls without such contacts were involved in this study. H. pylori status was determined by 13C-urea breath test. Serology was used to measure anti-H. pylori and anti-CagA IgG. Plasma gastrin, interleukin-8 and tumor necrosis factor-alpha were also determined. RESULTS: The H. pylori prevalence reached 97.6% in shepherds, 86% in their family members, but significantly less, 65.1%, in controls without contact with sheep. Anti-H. pylori IgG, anti-CagA in contact groups were significantly higher than in controls. Also, plasma gastrin, interleukin-8 and tumor necrosis factor-alpha had significantly higher values as compared to controls. CONCLUSIONS: Shepherds showed almost 100% H. pylori prevalence and higher incidence of CagA seropositivity, plasma gastrin and pro-inflammatory cytokine levels. Considering 100% positive 13C-urea breath test in sheep, it may be reasonable to suggest that H. pylori infection in shepherds and their family members originates from sheep and H. pylori infection might, therefore, be considered as zoonosis.     

Stem cell factor contributes to intestinal mucosal mast cell hyperplasia in rats infected with Nippostrongylus brasiliensis or Trichinella spiralis, but anti-stem cell factor treatment decreases parasite egg production during N brasiliensis infection

We assessed the effects of the c-kit ligand, stem cell factor (SCF), in the jejunal mucosal mast cell hyperplasia that occurs during infection with the intestinal nematodes, Nippostrongylus brasiliensis or Trichinella spiralis in rats. Compared with vehicle-treated rats, rats treated with SCF (25 micrograms/kg/d, intravenous [i.v.] for 14 days) during N brasiliensis infection exhibited significantly higher levels of the rat mucosal mast cell (MMC)-associated protease, rat mast cell protease II (RMCP II) in the jejunum and serum on day 8 of infection, but not on days 10 or 15 of infection. By contrast, in comparison to rats treated with normal sheep IgG, rats treated with a polyclonal sheep antirat SCF antibody exhibited markedly decreased numbers of jejunal MMCs, levels of jejunal RMCP II, and serum concentrations of RMCP II during infection with either nematode, particularly at the earlier intervals of infection (< or = day 10). Taken together, these findings indicate that SCF importantly contributes to MMC hyperplasia and/or survival during N brasiliensis or T spiralis infection in rats, but that levels of endogenous SCF are adequate to sustain near maximal MMC hyperplasia during infection with these nematodes. Notably, treatment of rats with SCF somewhat increased, and treatment with anti- SCF significantly decreased, parasite egg production during N brasiliensis infection. This finding raises the interesting possibility that certain activities of intestinal MMCs may contribute to parasite fecundity during infection with this nematode.     

Rare coincidence of eosinophilic esophagitis with esophageal stenosis and intramural pseudodiverticulosis.

We describe the first detailed case of eosinophilic esophagitis associated with esophageal intramural pseudodiverticulosis and gastro-esophageal reflux disease in a 24-year-old man, who suffered from recurrent dysphagia since the age of 3 years. He presented with symptoms of dysphagia, food impaction and malnutrition. An esophagogram revealed a high-grade stenosis in the proximal part of the esophagus. Histological evaluation of esophageal mucosal biopsies demonstrated more than 20 eosinophil granulocytes per high power field, indicative of eosinophilic esophagitis. Additionally, esophago-gastro-duodenoscopy showed pseudodiverticulosis in the distal portion of the esophagus. A therapeutic regimen consisting of topical steroid intake, antihistamines, proton-pump-inhibition and specific food avoidance led to significant clinical improvement within 6 weeks.     

Quantitative analysis of von Willebrand factor propeptide release in vivo: effect of experimental endotoxemia and administration of 1- deamino-8-D-arginine vasopressin in humans

The results of studies with cultured endothelial cells have shown that most von Willebrand factor (vWF) synthesized is directly secreted (constitutive pathway) and consists of both mature vWF, its precursor molecule pro-vWF, and the cleaved vWF prosequence. Only fully processed, functionally mature vWF is stored within the cell, together with the propeptide, and leaves the cell only on stimulation (regulated secretion). Both in resting and stimulated cultured endothelial cells, the stoichiometry of the released propeptide to the released mature vWF is essentially equimolar. In the present study, we have measured the molar ratio of propeptide to mature vWF in vivo, both under resting conditions and conditions that reflect activation of the endothelium. To this end, we devised a method that allows the measurement of the propeptide (vW antigen II) on a quantitative, is, molar basis, using purified recombinant propeptide as a standard. Our results show that the molar concentration of the propeptide in normal plasma is about one tenth of the concentration of mature vWF (expressed as half-dimer concentration). This ratio is approximately 1:1 in the medium of cultured endothelial cells. On administration in healthy subjects of either 1-deamino-8-D-arginine vasopressin or endotoxin, both agents being known to elicit an intravascular increase of vWF, the molar ratio of propeptide to mature vWF increased fourfold to fivefold. The propeptide concentration returned to baseline values after about 6 to 7 hours of injection of each stimulus, whereas the increase of mature vWF was much more sustained. Because the respective half-lives of mature vWF and its propeptide clearly differ, measurement of the concentration of these proteins could provide a means to assess the extent of activation of the endothelium under physiological and pathophysiological conditions.     

Irradiated B7-1 transduced primary acute myelogenous leukemia (AML) cells can be used as therapeutic vaccines in murine AML

Recent studies have shown that tumor cells genetically modified by transduction of B7-1, a natural ligand for the T-cell costimulatory molecules CD28 and CTLA-4, are rejected in syngeneic hosts. In these reports, transformed cell lines and drug-selected cells have been used for vaccinations. To determine the effectiveness of B7-1-transduced primary acute myelogenous leukemia (AML) cells on the induction of antitumor immunity, we have studied a murine AML model in which primary AML cells were retrovirally transduced with the murine B7-1 cDNA. A defective retroviral producer clone expressing B7-1 and secreting a high titer of virus was used for infection of AML cells. Unselected transduced AML cells, expressing a high level of B7-1, were used for in vivo vaccinations. Our results show that one intravenous (IV) injection of irradiated B7-1-positive (B7-1+) AML cells can provide long-lasting (5 to 6 months) systemic immunity against subsequent challenge with wild-type AML cells. Furthermore, one exposure to irradiated B7-1+ AML cells results in rejection of leukemia by leukemic mice when the vaccination occurs in the early stages of the disease. The antileukemia immunity is CD8+ T-cell-dependent and B7/CD28-mediated, since in vivo treatment of mice with anti-CD8 monoclonal antibody or CTLA-4 Ig leads to abrogation of the specific antileukemia immune response. These results emphasize that B7-1 vaccines may have therapeutic usefulness for patients with AML.     

Positive Coombs test in Hodgkin's disease: significance and implications

To clarify the clinicopathologic characteristics of Coombs' positivity in Hodgkin's disease, the records of 71 cases were reviewed. The direct Coombs test was positive in seven. Mean age of the seven was 22 yr (range 11-33). All were males. All had extensive disease (pathologic stage III or IV) and six had systemic (B) symptoms. Four had mixed cellularity; three had nodular sclerosis. The positive Coombs test was detected at original diagnosis in three and at time of relapse in four. Although all were anemic, only three had evidence of overt hemolysis. The antibody responsible for Coombs positivity was characterized in three and fulfilled the criteria for IgG anti-It. The presence of a positive direct Coombs test in the patient with Hodgkin's disease suggests active and advanced disease. The presence of IgG anti-It may represent a unique antibody in the Coombs-positive hemolytic anemia associated with Hodgkin's disease.     

食管球囊联合超细胃镜扩张贲门失弛缓症1例

对1例中年贲门失弛缓症患者于超细胃镜直视下应用食管球囊预扩张一次的基础上,将胃镜插至胃底反转对球囊定位后再次扩张.扩张口径满意,无穿孔；症状缓解,随访1mo无复发.