Fluorescence in situ hybridization improves the detection of 5q31 deletion in myelodysplastic syndromes without cytogenetic evidence of 5q-.

BACKGROUND: More than 50% of patients with myelodysplastic syndromes present cytogenetic aberrations at diagnosis. Partial or complete deletion of the long arm of chromosome 5 is the most frequent abnormality. The aim of this study was to apply fluorescence in situ hybridization of 5q31 in patients diagnosed with de novo myelodysplastic syndromes in whom conventional banding cytogenetics study had shown a normal karyotype, absence of metaphases or an abnormal karyotype without evidence of del(5q). DESIGN AND METHODS: We performed fluorescence in situ hybridization of 5q31 in 716 patients, divided into two groups: group A patients (n=637) in whom the 5q deletion had not been detected at diagnosis by conventional banding cytogenetics and group B patients (n=79), in whom cytogenetic analysis had revealed the 5q deletion (positive control group). RESULTS: In group A (n=637), the 5q deletion was detected by fluorescence in situ hybridization in 38 cases (5.96%). The majority of positive cases were diagnosed as having the 5q- syndrome. The deletion was mainly observed in cases in which the cytogenetics study had shown no metaphases or an aberrant karyotype with chromosome 5 involved. In group B (n=79), the 5q deletion had been observed by cytogenetics and was confirmed to be present in all cases by fluorescence in situ hybridization of 5q31. CONCLUSIONS: Fluorescence in situ hybridization of 5q31 detected the 5q deletion in 6% of cases without clear evidence of del(5q) by conventional banding cytogenetics. We suggest that fluorescence in situ hybridization of 5q31 should be performed in cases of a suspected '5q- syndrome' and/or if the cytogenetic study shows no metaphases or an aberrant karyotype with chromosome 5 involved (no 5q- chromosome).

Epstein-Barr virus is related with 5-aminosalicylic acid, tonsillectomy, and CD19(+) cells in Crohn's disease.

AIM: To study anti-Epstein-Barr virus (EBV) IgG antibodies in Crohn's disease in relation to treatment, immune cells, and prior tonsillectomy/appendectomy. METHODS: This study included 36 CD patients and 36 healthy individuals (controls), and evaluated different clinical scenarios (new patient, remission and active disease), previous mucosa-associated lymphoid tissue removal (tonsillectomy and appendectomy) and therapeutic regimens (5-aminosalicylic acid, azathioprine, anti-tumor necrosis factor, antibiotics, and corticosteroids). T and B cells subsets in peripheral blood were analyzed by flow cytometry (markers included: CD45, CD4, CD8, CD3, CD19, CD56, CD2, CD3, TCRαß and TCRγδ) to relate with the levels of anti-EBV IgG antibodies, determined by enzyme-linked immunosorbent assay. RESULTS: The lowest anti-EBV IgG levels were observed in the group of patients that were not in a specific treatment (95.4 ± 53.9 U/mL vs 131.5 ± 46.2 U/mL, P = 0.038). The patients that were treated with 5-aminosalicylic acid showed the highest anti-EBV IgG values (144.3 U/mL vs 102.6 U/mL, P = 0.045). CD19(+) cells had the largest decrease in the group of CD patients that received treatment (138.6 vs 223.9, P = 0.022). The analysis of anti-EBV IgG with respect to the presence or absence of tonsillectomy showed the highest values in the tonsillectomy group of CD patients (169.2 ± 20.7 U/mL vs 106.1 ± 50.3 U/mL, P = 0.002). However, in the group of healthy controls, no differences were seen between those who had been tonsillectomized and subjects who had not been operated on (134.0 ± 52.5 U/mL vs 127.7 ± 48.1 U/mL, P = 0.523). CONCLUSION: High anti-EBV IgG levels in CD are associated with 5-aminosalicylic acid treatment, tonsillectomy, and decrease of CD19(+) cells.

Deficit of interleukin 7 in septic patients.

We recently demonstrated an overall decrease of all αß and specially γδ T cell subsets in patients with sepsis compared with healthy subjects. IL-7 is a crucial factor for development of γδ T cells and survival in sepsis but its association with sepsis severity, evolution of organ failure and death still has not been investigated. Sera from 78 patients who met criteria for sepsis were analyzed vs control group. Septic patients showed the lowest levels of IL-7. Patients with severe sepsis reached levels of IL-7 higher than those observed in the groups of uncomplicated sepsis and septic shock. The frequency of γδ T cells at admission was lower in septic patients vs control group. At the time of admission, the frequency of γδ T cells in septic patients who subsequently died was lower than the observed in the group of patients that instead survived.

Association of γδ T cells with disease severity and mortality in septic patients.

Gamma-delta T cells are the most abundant of all epithelial-resident lymphocytes and are considered a first line of defense against pathogens in the mucosa. Our objective was to confirm the reduction in γδ T cell subsets and its relationship with mortality in patients with sepsis. We studied 135 patients with sepsis attended in the emergency department and intensive care unit of two hospitals and compared them with a similar control group of healthy subjects. The αß and γδ T cell subsets were determined via flow cytometry according to the stage of the sepsis and its relationship with mortality. All the lymphocyte subsets were reduced with respect to the corresponding subsets in the control group. All the γδ T cell populations decreased significantly as the septic picture worsened. Furthermore, γδ T cells showed decreases at days 2, 3, and 4 from the start of sepsis. Twenty-six patients with sepsis died (19.3%). The γδ T cells, specifically, the CD3(+) CD56(+) γδ T cells, were significantly reduced in those septic patients who died. Our results indicate that, during sepsis, γδ T cells show the largest decrease and this reduction becomes more intense when the septic process becomes more severe. Mortality was associated with a significant decrease in γδ T cells.

Microsporidia and its relation to Crohn's disease. A retrospective study.

BACKGROUND: The cause of Crohn's Disease (CD) remains unknown. Recently a decrease in the global lymphocyte population in the peripheral blood of CD patients has been reported. This decrease was more evident in γδ T lymphocytes, especially γδ CD8+T subsets. Furthermore, a decrease of IL-7 was also observed in these patients. We propose the hypothesis that microsporidia, an obligate intracellular opportunistic parasite recently related to fungi, in CD patients can take advantage of the lymphocytes and IL-7 deficits to proliferate and to contribute to the pathophysiology of this disease. METHODS AND FINDINGS: In this case-control study, serum samples were collected from 36 CD patients and from 36 healthy individuals (controls), IgE and IgG anti-Encephalitozoon antibodies were determined by ELISA; and forty-four intestinal tissue samples were analyzed through real time Polymerase Chain Reaction (PCR), twenty CD patients, nine with others diseases and 15 healthy subjects. We observed that IgE anti-Encephalitozoon levels were significantly higher in patients with CD: 0.386(±0.256) vs control group, 0.201(±0.147), P<0.001. However, IgG anti-Encephalitozoon values were significantly lower in CD patients: 0.361(±0.256) vs control group, 0.876(±0.380), P<0.001. In the group of CD patients, 6/20 (30%) were positive by real time PCR for microsporidia and, all the patients of the control group were negative by real time PCR. CONCLUSIONS: These results suggest that CD patients are a group at risk for microsporidiasis and, moreover that microsporidia may be involved as a possible etiologic factor of CD.