Michaela Cvanová

Immunogenomic analysis of insect bite hypersensitivity in a model horse population.

Equine insect bite hypersensitivity (IBH) is a seasonal IgE-mediated dermatosis caused by bites of insects of the genus Culicoides. A familial predisposition for the disease has been shown but, except for the MHC, the genes involved have not been identified so far. An immunogenomic analysis of IBH was performed in a model population of Old Kladruby horses, all living in the same environment. Clinical signs of IBH were used as phenotypic manifestation of IBH. Furthermore, total serum IgE levels were determined in the sera of these horses and used as an independent phenotypic marker for the immunogenetic analysis. Single nucleotide polymorphisms (SNPs) in candidate immunity-related genes were used for association analyses. Genotypes composed of two to five genes encoding interferon gamma -IFNG, transforming growth factor beta 1 -TGFB1, Janus kinase 2 -JAK2, thymic stromal lymphopoietin -TSLP, and involucrin -IVL were associated with IBH, indicating a role of the genes in the pathogenesis of IBH. These findings were supported by analysis of gene expression in skin biopsies of 15 affected and 15 unaffected horses. Two markers associated with IBH, IFNG and TGFB1, showed differences in mRNA expression in skin biopsies from IBH-affected and non-affected horses (p<0.05). Expression of the gene coding for the CD14 receptor molecule -CD14 was different in skin biopsies at p<0.06. When total IgE levels were treated as binary traits, genotypes of IGHE, ELA-DRA, and IL10/b were associated with this trait. When treated as a continuous trait, total IgE levels were associated with genes IGHE, FCER1A, IL4, IL4R, IL10, IL1RA, and JAK2. This first report on non-MHC genes associated with IBH in horses is thus supported by differences in expression of genes known to play a role in allergy and immunity.

MDR1 in Paroxetine-Induced Sexual Dysfunction

Paroxetine-induced sexual dysfunction represents a frequent treatment complication of otherwise efficient antidepressants. The genetic polymorphism of pharmacokinetic genes may contribute to the occurrence of such dysfunctions. This study presents the effect of MDR1 gene polymorphisms on sexual function in 18 women with bulimia nervosa, 18 women with anxiety disorders, and 19 healthy control subjects. It also deals with the relation between MDR1 gene polymorphisms and paroxetine-induced sexual dysfunction. The results demonstrated that MDR1 G2677T/A gene polymorphism allele carriers treated with paroxetine presented with difficulties with orgasm (p = .008) and lubrication (p < .001).

ATM and TGFB1 genes polymorphisms in prediction of late complications of chemoradiotherapy in patients with locally advanced cervical cancer.

The purpose of our study was to evaluate a possible correlation between genetic polymorphisms in ATM and TGFB1 genes and late toxicity of chemoradiotherapy for locally advanced cervical cancer. Fifty five patients with FIGO stage IIB and higher without a disease recurrence with a mean follow up of 6 years were included. Late toxicity was assessed by EORTC/RTOG late toxicity criteria. Univariate and multivariate logistic regression model was used for statistical analysis. Degree of association between polymorphisms and late toxicity of chemotherapy was assessed on the basis of phi-coefficient (φ) as well. We did not find any association between 5557G>A polymorphism in the ATM gene or single TGFB1 polymorphisms and late toxicity. TGFB1 compound homozygosity (-1552delAGG, -509C>T, L10P) was a significant predictive factor of grade III-IV and any grade of complications in both univariate and multivariate logistic regression analyses and statistical significance of association between polymorphisms and late toxicity of chemoradiotherapy was confirmed also by the evaluation of phi-coefficient (φ). We conclude that haplotypes instead of single nucleotide polymorphic sites in the genes may better characterize the individual radiosensitivity. Keywords: cervical cancer, radiotherapy, ATM, TGFB1, late toxicity.

Toxic epidermal necrolysis data from the CELESTE multinational registry. Part I: Epidemiology and general microbiological characteristics

INTRODUCTION Toxic epidermal necrolysis (TEN) is a rare, life-threatening autoimmune disease predominantly manifested in the skin and mucous membranes. Today, infectious complications have the dominant share in mortality of TEN patients. Due to the nature of the therapy and administration of immunosuppressive medications, a wide range of potentially pathogenic microorganisms, which cause infectious complications in different compartments in these patients, is not surprising. MATERIAL AND METHODOLOGY This is a multicentric study, which included all patients with TEN hospitalized between 2000-2015 in specialized centres in the Czech Republic and Slovakia. The total catchment area was over 12.5 million inhabitants. The actual implementation of the project was carried out using data obtained from the registry CELESTE (Central European LyEll Syndrome: Therapeutic Evaluation), when specific parameters relating to epidemiological indicators and infectious complications in patients with TEN were evaluated in the form of a retrospective analysis. RESULTS In total, 39 patients with TEN were included in the study (12 patients died, mortality was 31%), who were hospitalized in the monitored period. The median age of patients in the group was 63 years (the range was 4-83 years, the mean was 51 years), the median of the exfoliated area was 70% TBSA (total body surface area) (range 30-100%, mean 67%). SCORTEN was calculated for 38 patients on the day of admission. Its median in all patients was 3 (range 1-6; mean 3). Any kind of infectious complication in the study group was recorded in 33 patients in total (85%). In total, 30 patients (77%) were infected with gram-positive cocci, 27 patients (69%) with gram-negative rods, and yeast cells or fibrous sponge were cultivated in 12 patients (31%). A total of 32 patients (82%) were found to have infectious complications in the exfoliated area, 15 patients (39%) had lower respiratory tract infections, 18 patients (46%) urinary tract infections and 15 patients (39%) an infection in the bloodstream. The most common potentially pathogenic microorganism isolated in our study group was coagulase neg. Staphylococcus, which caused infectious complications in 24 patients. Enterococcus faecalis/faecium (19 patients), Pseudomonas aeruginosa (17 patients), Staphylococcus aureus (11 patients) and Escherichia coli (11 patients) were other most frequently isolated micro-organisms. CONCLUSION The published data were obtained from the unique registry of TEN patients in Central Europe. In the first part, we have succeeded in defining the basic epidemiological indicators in the group of patients anonymously included in this registry. The study clearly confirms that infectious complications currently play an essential role in TEN patients, often limiting the chances of survival. The study also shows a high prevalence of these complications in the period after 15days from the start of hospitalization, when most patients already have completely regenerated skin cover.

Effect of timing of tracheostomy on changes in bacterial colonisation of the lower respiratory tract in burned children

OBJECTIVE The study aims to evaluate the impact of early and late tracheostomy on microbiological changes in the airways in severely burned children. MATERIALS AND METHODS Early tracheostomy is sometimes performed within 3 days after the start of mechanical ventilation regular microbiological surveillance of the respiratory tract was done in all patients. From each sputum, tracheobronchial aspirate and bronchoalveolar lavage (BAL), a microscopic slide was made and the material was seeded in a culture medium. The standard culture media used for the growth of respiratory pathogens are blood agar, McConkey agar, VL agar and chocolate agar. The obtained values were statistically analysed. RESULTS In the observed period, a total of 68 children underwent mechanical ventilation in our department. A total of 31 (45.59%) children had undergone surgical tracheostomy (18 patients with early tracheostomy and 13 patients with late tracheostomy). The most common bacterium isolated from the lower respiratory tract in patients with early and late tracheostomy was Acinetobacter baumannii (31.53% resp. 44.30% of all bacterial strains). In patients with early tracheostomy, the ratio of G+/G- during the 6-7th day of mechanical ventilation was 1.29:1 and during the 8-10th day, 1:1.43. In patients with late tracheostomy the G+/G- ratio was 1:2.25 and during the 8-10th day, 1:2.25. There was not any statistically significant deviation in the G+/G- ratio in patients with early and late tracheostomy in any of the monitored periods. CONCLUSION The main reasons for performing early tracheostomy are: extent, localisation and depth of the burn. Difficult weaning in an uncooperative patient, failure of extubation with subsequent reintubation and other complications may be an indication for late tracheostomy. The study confirms that the use of appropriately indicated early tracheostomy provides a microbiological benefit for burned children.

Predicting factors for locoregional failure of high-dose-rate brachytherapy for early-stage oral cancer

AIM Brachytherapy is an alternative to surgery in the treatment of the early stages of oral tongue cancer. The aim of this retrospective study was to analyze the clinical risk factors and possible candidate biomarkers of local and regional tumor control. PATIENTS & METHODS Twenty-four patients were treated between the years 2001 and 2010. Median follow-up was 37.4 months. Correlation between disease-free survival and clinical stage, tumor grade, resection margin, depth of invasion, and p16, EGF receptor, NF-κB, HIF-1α, HER2, Ku-80, COX-2 and VEGF expression was evaluated. RESULTS The estimated 5-year local control was 81% and locoregional control was 62%. Depth of tumor invasion (p = 0.018) and higher VEGF expression (p = 0.016) were significantly predictive for worse disease-free survival in Cox multivariate analysis. CONCLUSION Intensity of VEGF expression and depth of tumor invasion may be significantly negative predictors of disease-free survival in tongue cancer patients treated by brachytherapy alone. Predictive value of VEGF deserves evaluation in larger studies.

Toxic epidermal necrolysis data from the CELESTE multinational registry. Part II: Specific systemic and local risk factors for the development of infectious complications

The aim of the study was to identify the most important systemic and local risk factors for the development of infectious complications in patients with toxic epidermal necrolysis (TEN). MATERIAL AND METHODOLOGY This is a multicentric study that included all patients with TEN who were hospitalized between 2000-2015 in specialized centres in the Czech Republic and Slovakia. The total catchment area included a population of over 12.5 million inhabitants. The actual implementation of the project was carried out using data obtained from the CELESTE (Central European LyEll Syndrome: Therapeutic Evaluation) registry, wherein specific parameters related to epidemiological indicators and infectious complications in patients with TEN were evaluated as a retrospective analysis. RESULTS A total of 38 patients (97%) of the group were treated with corticosteroids. The comparison of patients with different doses of corticosteroids did not exhibit a statistically significant effect of corticosteroid administration on the development of infectious complications (p=0.421). There was no effect of the extent of the exfoliated area on the development of infectious complications in this area. The average extent of the exfoliated area was 66% TBSA (total body surface area) in patients with reported infectious complications and 71% TBSA (p=0.675) in patients without infectious complications. In the case of the development of an infectious complication in the bloodstream (BSI), the increasing effect of the SCORTEN (SCORe of Toxic Epidermal Necrosis) value was monitored during hospitalization. Within 5days from the beginning of the hospitalization, the average SCORTEN value was 2.7 in 6 patients with BSI and 3.0 in 32 patients without BSI (p=0.588). In the period after the 15th day of hospitalization, 7 patients with BSI had an average SCORTEN value of 3.4, and 16 patients without BSI had an average SCORTEN value of 2.5 (p=0.079). In the case of low respiratory tract infection (LRTI), the effects of the necessity for artificial pulmonary ventilation and the presence of tracheostomy were monitored. The statistically significant effect of mechanical ventilation on the development of LRTI occurred only during the period of 11-15days from the beginning of the hospitalization (p=0.016). The effect of the tracheostomy on the development of LRTI was proven to be more significant. CONCLUSION We did not find any statistically significant correlation between the nature of immunosuppressive therapy and the risk of developing infectious complications. We failed to identify statistically significant risk factors for the development of BSI. Mechanical ventilation and tracheostomy increase the likelihood of developing LRTIs in patients with TEN.

The role of antithrombin in patients with toxic epidermal necrolysis

Toxic epidermal necrolysis (TEN) is a rare systemic disease, which is predominantly manifested in the skin and mucous membranes. Its indicated incidence in the population is 0.5–1.5 cases per million inhabitants a year. It is the most severe syndrome from the SCARs group (Severe Cutaneous Adverse Reactions) with mortality around 30–50%.