Effect of Graphene Oxide and Silver Nanoparticle Hybrid Composite on Acinetobacter baumannii Strains, Regarding Antibiotic Resistance and Prevalence of AMP-C Production.

Background and Objectives: Growing antibiotic resistance among bacteria is a global issue that is becoming harder and more expensive to solve. Traditional treatment options are becoming less effective, causing more fatal outcomes of nosocomial infections. Since the development of new antibiotics has stagnated in the last decade, a novel approach is needed. Materials and Methods: Graphene-based materials are being developed and tested for various applications, and the medical field is no exception. We tested 98 clinical A. baumannii strains for antibiotic resistance, AMP-C production and the effectiveness of a graphene oxide and silver nanoparticle hybrid nanocomposite. The disc diffusion method was used to determine antibiotic susceptibility results. Antibiotic discs containing cefotaxime, cloxacillin and clavulanate were used to detect AMP-C production. The effectiveness of the GO-Ag hybrid nanocomposite was determined by counting colony forming units (CFUs) after a suspension of A. baumannii and the GO-Ag hybrid nanocomposite was plated on MH agar and incubated overnight to grow colonies. Results: In our research, we found that A. baumannii strains are resistant to the majority of commonly used antibiotics. Antibiotic resistance levels and AMP-C production can be factors, indicating the better effectiveness of the graphene oxide and silver nanoparticle hybrid nanocomposite. Conclusions: In this study, a GO-Ag hybrid nanocomposite was shown to have the potential to fight even the most problematic bacteria like A. baumannii.

Antiphospholipid antibodies and the risk of thrombosis in myeloproliferative neoplasms.

The morbidity and mortality of BCR-ABL-negative myeloproliferative neoplasia (MPN) patients is highly dependent on thrombosis that may be affected by antiphospholipid antibodies (aPLA) and lupus anticoagulant. Our aim was to evaluate the association of the aPLA together with platelet receptor glycoprotein (GP) Ia/IIa c.807C>T CT/TT genotypes and thrombotic complications in patients with MPNs. The study included 108 patients with BCR-ABL-negative MPN with data of previous thrombosis. Two different screening and one confirmatory test for the lupus anticoagulant were performed. Thrombotic complications were present in 59 (54.6%) subjects. aPLA were more frequently found in MPN patients with thrombosis vs no thrombosis (25.4 and 6.1%; p = 0.007). MPN patients with arterial thrombosis were more frequently positive for aPLA vs no arterial thrombosis (38.8 and 11.9%; p = 0.001). aPLA were more frequently found in patients with cerebrovascular events vs other arterial thrombotic complications or no thrombosis, respectively (39.3, 6.1, and 12.9%; p < 0.001). MPN patients with thrombosis were more frequently positive with aPLA and had platelet receptor GP Ia/IIa c.807C>T CT/TT genotypes compared to MPN patients without thrombosis (18.6 and 2.0%; p = 0.006). aPLA alone or with coexistence with platelet receptor GP Ia/IIa c.807C>T CT/TT polymorphism could be associated with thrombotic complications in patients with MPN.

IL-6 597A/G (rs1800797) and 174G/C (rs1800795) Gene Polymorphisms in the Development of Cervical Cancer in Lithuanian Women.

Our study aimed to evaluate the distribution of genotypes and allele frequencies of IL-6 597A/G (rs1800797) and 174G/C (rs1800795) polymorphisms in HPV infected and uninfected healthy women and cervical cancer patients. A PCR based Multiplex HPV genotyping test kit was used for in vitro detection and differentiation of high risk HPV genotypes. Genotyping of two polymorphisms, IL-6 597A/G (rs1800797) and 174G/C (rs1800795), was performed using the KASP genotyping assay kit. Cervical cancer patients were more likely to be HPV positive than control patients. Allele C of IL-6 rs1800795 was associated with a higher risk of cervical cancer by 2.26-fold and genotype CC by 5.37-fold. Genotype CC of IL-6 rs1800795 was more frequent in the HPV positive group compared with the HPV negative group (p = 0.002). Allele G of IL-6 rs1800797 was more frequently found in women with HPV16/HPV18 compared to other HPV types (p = 0.045). Women with AA genotypes of IL-6 rs1800797 were less frequently infected with HPV16/HPV18 compared to other HPV types (p = 0.045). The major finding of the study is the significant association of C allele and CC genotype of IL-6 1800795 gene with cervical cancer in the Lithuanian population. Genotype CC of IL-6 rs1800795 has a significant association with HPV infection as well.

Effects of Different Bone Substitutes on Reactive Oxygen Species Release in Leukocytes in Vitro: A Pilot Study.

PURPOSE: To evaluate the formation of reactive oxygen species in human leukocytes promoted by bone substitutes that are different in origin and morphology used for jawbone tissue regeneration. MATERIALS AND METHODS: This preclinical prospective randomized crossover study involved 10 subjects, from whom venous blood samples were taken. Leukocytes were separated and standardized. Sixty experimental samples consisted of leukocytes incubated with allogeneic, xenogeneic, or alloplastic bone substitutes at different bone weights (12.5 and 25 mg). The control samples consisted only of incubated leukocytes. Reactive oxygen species were quantitatively determined with the fluorimetric method. Statistical analysis was carried out using SPSS 23 software. RESULTS: The highest average reactive oxygen species values were obtained in the allogeneic bone substitute group (P < .05), while the xenogeneic bone substitute group and control group presented equal reactive oxygen species formation rates (P > .05). A proportional difference (P < .05) of reactive oxygen species emission was obtained between different masses of bone substitute in the samples. CONCLUSION: Allogeneic and alloplastic bone substitutes affect leukocytes and promote reactive oxygen species emission. Xenogeneic bone substitute presents no leukocyte stimulation and maintains anti-inflammatory conditions. Larger bone substitute mass provokes greater oxidative stress.

Circulating inflammatory markers in cervical cancer patients and healthy controls.

There is increasing evidence that host inflammatory responses play an important role in the development and progression of cancers. There are some data that cancer is associated not only with inflammation at the site of the lesion, but also with dysregulations of the host overall systemic immune response. In the case of cervical cancer, inflammation is an important factor associated with the development, progression, and potential metastasis of the disease. What is unclear still in the potential for modifications of host responses to human papillomaviruses (HPV) - a known causative agent of CC, that could be induced by cigarette smoking. In particular, it remains to be determined how the inflammation induced by HPV infection could impact on CC incidence/severity. In this prospective study, serum levels of 10 cytokines were evaluated using Multiplex and ELISA assays. The samples were the sera of 43 CC patients and 60 healthy (NILM) controls. All outcomes were evaluated in relation to host HPV and to their smoking status. The results in indicated that serum sTREM-1, TNFα, IFNß, IL-1ß, and IL-6 levels were significantly increased in CC (HPV+) patients compared to healthy NILM controls. A similar trend was observed for IL-10 and IL-2 levels. Within the two groups, differences in cytokine levels between smokers and never smokers were not remarkable. The findings here support the hypothesized role of systemic inflammation in the pathophysiology of CC.

Coagulation System Disorders and Thrombosis Prophylaxis During Laparoscopic Fundoplications.

BACKGROUND: The aim of this study was to assess and recommend the optimal deep vein thrombosis (DVT) prophylaxis regimen during and after laparoscopic fundoplication according to the blood coagulation disorders and the rate of DVT in 2 patient groups, receiving different DVT prophylaxis regimens. MATERIALS AND METHODS: This was a prospective randomized, single-center clinical study. The study population, 121 patients, were divided into 2 groups: group I received low-molecular-weight heparin 12 hours before the operation; group II received low-molecular-weight heparin only 1 hour before the laparoscopic fundoplication. Both groups received intermittent pneumatic compression during the entire procedure. Bilateral Doppler ultrasound to exclude DVT was performed before the surgery. Venous phase computed tomographic images were acquired from the ankle to the iliac tubercles on the third postoperative day to determine the presence and location of DVT. Hypercoagulation state was assessed by measuring the prothrombin fragment F1+2 (F1+2), the thrombin-antithrombin complex (TAT), and tissue factor microparticles activity (MP-TF) in plasma. The hypocoagulation effect was evaluated by measuring plasma free tissue factor pathway inhibitor (fTFPI). RESULTS: F1+2, TAT, and MP-TF indexes increased significantly, whereas fTFPI levels decreased significantly during and after laparoscopic fundoplication, when molecular-weight heparin was administered 12 hours before the operation. Computed tomography venography revealed peroneal vein thrombosis in 2 group I patients on the third postoperative day. Total postsurgical DVT frequency was 1.65%: 3.6% in group I, with no DVT in group II. CONCLUSION: Molecular-weight heparin and intraoperative intermittent pneumatic compression controls the hypercoagulation effect more efficiently when it is administered 1 hour before surgery: it causes significant reduction of F1+2, TAT, and MP-TF indexes and significant increases of fTFPI levels during and after laparoscopic fundoplication.

Comparative Analysis of Blood Clot, Plasma Rich in Growth Factors and Platelet-Rich Fibrin Resistance to Bacteria-Induced Fibrinolysis.

Alveolar osteitis (AO) is a common, painful postoperative complication after tooth extraction. Fibrinolytic activity in the extraction socket is one etiological factor. Platelet concentrates are used to prevent and treat AO. The aim of this study was to find out whether the positive effect of platelet concentrates can be related to resistance to bacteria-induced fibrinolysis. Blood from 45 human volunteers was used to prepare four media: blood clot medium as control group; PRF and PRGF first fraction (PRGF I) and PRGF second fraction (PRGF II) as study groups. Additionally, collected blood was used for blood plasma preparation on which evaluation of initial value of d-dimer concentration was performed. A solution of five different microbes (Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumonia, Bacillus cereus, and Candida albicans) was adjusted to 0.5 McFarland (1 × 108 CFU/mL) and then diluted to 0.25 McFarland (0.5 × 108 CFU/mL). The d-dimer concentration was evaluated after one and three hours of bacteria exposure. The resistance to fibrinolysis was not statistically distinguished among any media groups at any time. S. pneumoniae was statistically active in PRF after three hours. C. albicans was statistically active in PRGF II after one hour and in PRF between the first and third hour and after three hours. S. aureus and B. cereus were statistically active in PRGF II after three hours. S. pyogenes was statistically active after one hour, between the first and third hour, and after the third hour in all groups. S. pyogenes was the most active bacterium. Different blood formulations were not distinguishable based on resistance to bacteria-induced fibrinolysis. Low fibrinolytic properties of the found major microbes suggests that bacteria-induced fibrinolysis is one of the leading causes of absence of a clot in a post-extraction socket to be clinically insignificant. The initial absence of a clot or its mechanical elimination during formation or the healing period are major causes of dry socket.

Organised Versus Opportunistic Cervical Cancer Screening in Urban and Rural Regions of Lithuania.

Background and Objectives: In 2004, Lithuania started the Nationwide Cervical Cancer Screening Programme. However, screening is more opportunistic than population-wide and the programme's coverage is insufficient. The aim of this study was to assess the effect of systematic personal invitation on coverage of cervical cancer (CC) screening in urban and rural regions of Lithuania. Materials and Methods: The study was conducted in an urban primary healthcare centre (PHCC) and in a rural PHCC, where prevailing CC screening practice was highly opportunistic. Over the first year, all women aged 25-60 who had not received a Pap smear test within the last three years in urban (n = 1591) and rural (n = 1843) PHCCs received a personal invitation letter to participate in the screening. Over the second year, the reminder letter was sent to the non-attendees (n = 1042 in urban and n = 929 in rural PHCCs). A random sample of women (n = 93), who did not attend for screening after two letters, was contacted by phone in order to identify the barriers of non-attendance. Results: Before the study, only 9.6% of the target population in urban and 14.7% in rural PHCCs participated in CC screening. After the first invitation letter, the participation in CC screening increased up to 24.6% in urban and 30.8% in rural areas (p < 0.001). After the reminder letter, the attendance was 16.4% in urban and 22.2% in rural PHCCs (p < 0.001). The most common barriers for the non-attendance were lack of time, long waiting time for family doctor's appointment, worries that a Pap test might be unpleasant and preventive gynaecological examination outside of the screening program. Conclusions: A systematic personal invitation with one reminder letter significantly increased the coverage of CC screening and was more effective in rural regions than in urban regions. The assessed barriers for non-attendance can be used to improve the coverage of screening.

Associations among Serum Lipocalin-2 Concentration, Human Papilloma Virus and Clinical Stage of Cervical Cancer.

Background and objective: Lipocalin 2 (LCN2) has an oncogenic role in promoting tumorigenesis through enhancing tumor cell proliferation and the metastatic potential. The aim of our study was to determine whether serum LCN2 could serve as a diagnostic marker of cervical cancer (CC) and to evaluate the correlation between its serum concentration, the clinical stage of the cancer and Human Papilloma Virus HPV infections in women. Materials and methods: A total of 33 women with histologically proven cervical cancer (CC), 9 women with high- grade cervical intraepithelial neoplasia (HSIL) and 48 healthy women (NILM) were involved in the study. A concentration of LCN2 was assayed with the Magnetic LuminexR Assay multiplex kit. An HPV genotyping kit was used for the detection and differentiation of 15 high-risk (HR) HPV types in the liquid-based cytology medium (LBCM) and the tissue biopsy. Results: The majority (84.8%) of the women were infected by HPV16 in the CC group, and there was no woman with HPV16 in the control group (P < 0.01). Several types of HR HPV were found more often in the LBCM compared to in the tissue biopsy (P = 0.044). HPV16 was more frequently detected in the tissue biopsy than the LBCM (P < 0.05). The LCN2 level was higher in HPV-positive than in HPV-negative women (P = 0.029). The LCN2 concentration was significantly higher in women with stage IV than those with stage I CC (P = 0.021). Conclusions: Many HR HPV types, together with HPV16/18, can colonize the vagina and cervix, but often HPV16 alone penetrates into the tissue and causes CC. The serum LCN2 concentration was found to be associated not only with HR HPV infection, irrespective of the degree of cervical intraepithelial changes, but also with advanced clinical CC stage. LCN2 could be used to identify patients with advanced disease, who require a more aggressive treatment.

Psychological and Physiological Biomarkers of Neuromuscular Fatigue after Two Bouts of Sprint Interval Exercise.

The main aim of our study was to determinate whether a repeated bout (RB) (vs. first bout [FB]) of sprint interval cycling exercise (SIE) is sufficient to mitigate SIE-induced psychological and physiological biomarker kinetics within 48 h after the exercise. Ten physically active men (age, 22.6 ± 5.2 years; VO2max, 44.3 ± 5.7 ml/kg/min) performed the FB of SIE (12 repeats of 5 s each) on one day and the RB 2 weeks later. The following parameters were measured: motor performance (voluntary, electrically induced and isokinetic skeletal muscle contraction torque, and central activation ratio [CAR]); stress markers [brain-derived neurotrophic factor (BDNF), cortisol, norepinephrine, and epinephrine]; inflammatory markers (IL-6, IL-10, and TNF-α); metabolic markers (glucose and lactate); muscle and rectal temperature; cycling power output; and psychological perceptions. The average cycling power output and neuromuscular fatigue after exercise did not differ between the FB and RB. There were significant decreases in cortisol and BDNF concentration at 12 h (P < 0.05) and 24 h (P < 0.001) after the FB, respectively. The decrease in cortisol concentration observed 12 h after exercise was significantly greater after the RB (P < 0.05) than after the FB. The immune-metabolic response to the RB (vs. FB) SIE was suppressed and accompanied by lower psychological exertion. Most of the changes in psychological and physiological biomarkers in the FB and RB were closely related to the response kinetics of changes in BDNF concentration.

Associations of HLA DRB1 alleles with IgG oligoclonal bands and their influence on multiple sclerosis course and disability status.

BACKGROUND AND AIM: Oligoclonal bands (OCB) may be associated with the genes of HLA complex, which allows to consider the possible interaction of genetic and immunological factors and its importance in the development and progression of multiple sclerosis (MS). The aim of this study was to evaluate the associations between HLA DRB1 alleles and oligoclonal bands (OCBs) in the disease course and disability of multiple sclerosis (MS) patients. MATERIALS AND METHODS: This was a prospective study of 120 patients with MS. HLA DRB1 alleles were genotyped using the polymerase chain reaction. Matched cerebrospinal fluid (CSF) and plasma samples were analyzed using isoelectric focusing and IgG specific immunofixation to test for the presence of intrathecal specific OCB. RESULTS: HLA DRB1*08 allele was related to a lower degree of disability. Oligoclonal bands were an independent and significant factor that influenced disability status irrespective of HLA DRB1* 04, *07, *08, *13, *15 and *16 alleles. Age at the onset and duration of the disease were independent and significant factors for MS progression in all logistic regression models with each newly added HLA DRB1 allele. HLA DRB1*08 allele was related to 75% lower odds that relapsing remitting (RR) MS will change to a progressive course MS irrespective of the other factors investigated. Detection of OCBs in the CSF was associated with the higher possibility of RR MS progression in all cases, except when the *08 allele was present. CONCLUSIONS: OCBs had an influence on disability status, while HLA DRB1*08 allele was significantly associated with lower possibility that RR MS will change to progressive course MS.

Duffy and kidd genotyping facilitates pretransfusion testing in patients undergoing long-term transfusion therapy.

OBJECTIVE: Conventional serologic typing of red blood cell systems other than ABO and RhD can be inaccurate and difficult to interpret in patients who have recently undergone blood transfusion. While molecular-based assays are not used routinely, the usefulness of genotyping was investigated in order to determine patients who may benefit from this procedure. MATERIALS AND METHODS: Blood samples were taken from 101 patients with haemato-oncological, chronic renal, or gastroenterological diseases and from 50 donor controls; the samples were tested for Fya and Fyb by applying serologic and genetic methods. All patients had received 3 or more units of RBCs during the last 3 months. An average of 6.1 RBC units were transfused per patient. The average length of time from transfusion until blood sampling was 24.4 days. The haemagglutination test was applied for serological analysis, and the restriction length polymorphism assay was used for genotyping. RESULTS: In total, 33 (32.7%) patients showed positive reactions with anti-Fya or anti-Fyb while being negative genetically. False-positive Fya results were found in 23 samples, and false-positive Fyb in 10 specimens. During the last 3 months, significantly more RBC units were transfused to patients with discrepant results than to those with accurate phenotyping/genotyping results: median of 5 (mean ± SE: 6.85±0.69) versus median of 4 (mean: 5.71±0.51), respectively (p=0.025). The median length of time after the last transfusion was 25 days (mean: 28.72±2.23 days) in the group with accurate phenotyping/genotyping results versus a median of 14 days (mean: 15.52±1.95 days) in the group with discrepant results (p=0.001). Phenotypes and genotypes coincided in all donor samples. CONCLUSION: Genotyping assays for the Duffy system should be considered if the patient underwent blood transfusion less than 3 or 4 weeks before the sample collection. If the time frame from RBC transfusion exceeds 6 weeks, Duffy phenotyping can provide accurate results.

Time course of physiological and psychological responses in humans during a 20-day severe-cold-acclimation programme.

The time course of physiological and psychological markers during cold acclimation (CA) was explored. The experiment included 17 controlled (i.e., until the rectal temperature reached 35.5°C or 170 min had elapsed; for the CA-17 session, the subjects (n = 14) were immersed in water for the same amount of time as that used in the CA-1 session) head-out water immersions at a temperature of 14°C over 20 days. The data obtained in this study suggest that the subjects exhibited a thermoregulatory shift from peripheral-to-central to solely central input thermoregulation, as well as from shivering to non-shivering thermogenesis throughout the CA. In the first six CA sessions, a hypothermic type of acclimation was found; further CA (CA-7 to CA-16) led to a transitional shift to a hypothermic-insulative type of acclimation. Interestingly, when the subjects were immersed in water for the same time as that used in the CA-1 session (CA-17), the CA led to a hypothermic type of acclimation. The presence of a metabolic type of thermogenesis was evident only under thermoneutral conditions. Cold-water immersion decreased the concentration of cold-stress markers, reduced the activity of the innate immune system, suppressed specific immunity to a lesser degree and yielded less discomfort and cold sensation. We found a negative correlation between body mass index and Δ metabolic heat production before and after CA.

The importance of HLA DRB1 gene allele to clinical features and disability in patients with multiple sclerosis in Lithuania.

BACKGROUND: The association of HLA DRB1 alleles with susceptibility to multiple sclerosis (MS) has been consistently reported although its effect on the clinical features and disability is still unclear probably due to diversity in ethnicity and geographic location of the studied populations. The aim of the present study was to investigate the influence of HLA DRB1 alleles on the clinical features and disability of the patients with MS in Lithuania. METHODS: This was a prospective study of 120 patients with MS. HLA DRB1 alleles were genotyped using the polymerase chain reaction. RESULTS: The first symptoms of MS in patients with HLA DRB1*15 allele manifested at younger age than in those without this allele (28.32 +/- 5.49 yrs vs. 30.94 +/- 8.43 yrs, respectively, p = 0.043). HLA DRB1*08 allele was more prevalent among relapsing-remitting (RR) MS patients than among patients with progressive course of MS (25.0% vs. 8.3%, respectively, chi^2 = 6.000, p = 0.05). MS patients with this allele had lower relapse rate than those without this allele (1.00 +/- 0.97 and 1.44 +/- 0.85, respectively, p = 0.043). Degree of disability during the last visit was lower among the patients with HLA DRB1*08 allele (EDSS score 3.15 +/- 1.95 vs. 4.49 +/- 1.96, p = 0.006), and higher among those with HLA DRB1*15 allele (EDSS score 4.60 +/- 2.10 vs.4.05 +/- 1.94, p = 0.047) compared to patients without these alleles but there were no significant associations between these alleles and the duration of the disease to disability. HLA DRB1*08 allele (OR = 0.18, 95% CI 0,039-0,8, p = 0.029) was demonstradet to be independent factor to take a longer time to reach an EDSS of 6, while HLA DRB1*01 allele (OR = 5.92, 95% CI 1,30-26,8, p = 0.021) was related in a shorter time to reach and EDSS of 6. Patients with HLA DRB1*08 allele had lower IgG index compared to patients without this allele (0.58 +/- 0.17 and 0.73 +/- 0.31, respectively, p = 0.04), and HLA DRB1*15 allele was more often found among MS patients with oligoclonal bands (OCBs) in cerebrospinal fluid than among those without OCBs (OR 2.3, CI 95% 1.017-5.301; p = 0.043). CONCLUSIONS: HLA DRB1*15 allele was related with an earlier manifestation of the first MS symptoms, progressive course of the disease and higher degree of disability. HLA DRB1*08 allele was more prevalent among the RR MS patients and was associated with the lower rate of relapse, degree of disability and IgG index.

Frequency of HLA-DRB1 gene alleles in patients with multiple sclerosis in a Lithuanian population.

The aim of the present study was to investigate the influence of HLA-DRB1 alleles on the genetic susceptibility to multiple sclerosis in the Lithuanian population. MATERIAL AND METHODS. A total of 120 patients with multiple sclerosis and 120 unrelated healthy controls were enrolled in this case-control study. Allelic frequencies were compared between the groups. HLA-DRB1 alleles were genotyped using the polymerase chain reaction. RESULTS. HLA-DRB1*15 was present in 55.8% of the patients with multiple sclerosis and 10.0% of the controls (OR, 5.58; 95% CI, 3.19-9.77; P<0.0001). The protective alleles that were found to be more prevalent among the controls compared with the patients with multiple sclerosis were HLA-DRB1*01 (26.7% vs. 7.5%, P<0.0001), *03 (17.5% vs. 8.3%, P=0.034), and *16 (11.7% vs. 3.3%, P=0.014). HLA-DRB1*15 was more common among the female patients with multiple sclerosis than among the male patients (68.4% vs. 34.1%; OR, 4.18; 95%, CI 1.90-9.22; P=0.001). The heterozygous inheritance of HLA-DRB1*15 allele was more common in the patients with a history of maternal multiple sclerosis than in those with a history of paternal multiple sclerosis (29.4% vs. 9.8%; P=0.045). CONCLUSIONS. HLA-DRB1*15 was found to be associated with multiple sclerosis in the Lithuanian population. This allele was more prevalent among the female patients with multiple sclerosis. Maternal multiple sclerosis was more common than paternal multiple sclerosis, but the relationship with HLA-DRB1*15 allele was not established. HLA-DRB1*01, *03, and *16 appeared to be the protective alleles in this series.

Changes in the dependence of Pseudomonas aeruginosa O serogroup strains and their resistance to antibiotics in a university hospital during a 5-year period.

UNLABELLED: The aim of our study was to determine the changes in antibiotic resistance and O serogroup dependence of P. aeruginosa strains isolated from lower respiratory tract specimens of patients in 2003 and 2008; the patients were treated in intensive care units of the biggest treatment facility in Lithuania (Hospital of Lithuanian University of Health Sciences, HLUHS, former Hospital of Kaunas University of Medicine) MATERIAL AND METHODS: The study included 90 P. aeruginosa strains serotyped in 2003 and 101 P. aeruginosa strains serotyped in 2008, which were randomly selected. The resistance of P. aeruginosa strains was determined by the disc diffusion method based on the standard guidelines. The sizes of inhibition zones were interpreted according to the National Committee for Clinical Laboratory Standards (M(2)-A(6)). Isolates were serotyped using sera with specific antibodies against the O antigens of P. aeruginosa (Bio-Rad, France). RESULTS: Comparison of changes in the distribution of P. aeruginosa serogroups in 2003 and 2008 showed that P. aeruginosa strains of serogroups O:1, O:2, and O:3 were more prevalent in 2003 as compared with 2008 (23.3%, n=21; 27.8%, n=25; 12.2%, n=11 vs. 9.9%, n=10; 10.9%, n=11; 4.0%, n=4, P<0.05). P. aeruginosa strains of serogroups O:6 and O:11 were isolated more frequently in 2008 than 2003 (26.7%, n=27; 34.7%, n=35 vs. 4.4%, n=4; 10.0%, n=9, P<0.001). The results showed that 18 of the 90 P. aeruginosa strains in 2003 and 25 of the 101 P. aeruginosa strains in 2008 were resistant to three or more antibiotics tested, i.e., they were multidrug-resistant. Analysis of the distribution of serogroups among these P. aeruginosa strains isolated in 2003 and 2008 revealed a significantly higher frequency of O:11 serogroup than other serogroups. Meanwhile, in the group of nonmultidrug-resistant P. aeruginosa strains, P. aeruginosa O:11 serogroup strains were identified less frequently and accounted only for 2.8% (n=2, P<0.001) of the isolates in 2003 and 27.6% (n=21, P<0.01) in 2008. CONCLUSIONS: During the 5-year period, the isolation rate of P. aeruginosa strains belonging to serogroup O:11 increased. P. aeruginosa strains isolated in 2003 and 2008 belonging to serogroup O:11 were more frequently multidrug resistant. The increasing resistance of P. aeruginosa to reserve antibiotics of carbapenem group was observed.

Changes in antibiotic resistance level of nosocomial Pseudomonas aeruginosa isolates in the largest university hospital of Lithuania.

UNLABELLED: The aim was to estimate changes in the resistance rates of Pseudomonas aeruginosa (P. aeruginosa) strains isolated from patients treated in intensive care units of the largest university hospital. MATERIALS AND METHODS: Isolates were identified with the Phoenix ID system (Becton Dickinson, USA). The minimum inhibitory concentration (MIC) of ceftazidime, ciprofloxacin, and amikacin were determined by the E-test and evaluated following the recommendations of the Clinical Laboratory Standards Institute. RESULTS: In 2003, the proportion of P. aeruginosa strains resistant to piperacillin was greatest followed by strains resistant gentamicin and ciprofloxacin. In 2008, the resistance rates markedly changed being the highest to ciprofloxacin. An increase in the resistance rates to ciprofloxacin (+24%, P<0.001) and ceftazidime (+8.3%, P<0.05) was documented. In 2003, there were 66.7% of P. aeruginosa strains sensitive to all antibiotics tested, and this percentage decreased to 47.5% in 2008 (P<0.05). During the study, a significant increase in the median MICs for ciprofloxacin and amikacin was observed (P<0.001); however, no significant change was documented for ceftazidime. CONCLUSIONS: P. aeruginosa remains an important nosocomial pathogen with relatively high overall resistance to antimicrobial agents, and the resistance level is increasing.

Characteristics of carbapenem-resistant Pseudomonas aeruginosa strains in patients with ventilator-associated pneumonia in intensive care units.

UNLABELLED: The aim of this study was to determine the characteristics of carbapenem-resistant Pseudomonas aeruginosa (P. aeruginosa) strains and 5-year changes in resistance in a tertiary university hospital. MATERIAL AND METHODS: The study included 90 and 101 randomly selected P. aeruginosa strains serotyped in 2003 and 2008, respectively. The standardized disk diffusion test and E-test were used to determine resistance to antibiotics. P. aeruginosa strains were considered to have high-level resistance if a minimum inhibitory concentration (MIC) for imipenem or meropenem was >32 µg/mL. To identify serogroups, sera containing specific antibodies against O group antigens of P. aeruginosa were used. P. aeruginosa isolates resistant to imipenem or/and meropenem were screened for metallo-ß-lactamase (MBL) production by using the MBL E-test. RESULTS: Comparison of the changes in resistance of P. aeruginosa strains to carbapenems within the 5-year period revealed that the level of resistance to imipenem increased. In 2003, 53.3% of P. aeruginosa strains were found to be highly resistant to imipenem, while in 2008, this percentage increased to 87.8% (P=0.01). The prevalence of MBL-producing strains increased from 15.8% in 2003 to 61.9% in 2008 (P<0.001). In 2003 and 2008, carbapenem-resistant P. aeruginosa strains were more often resistant to ciprofloxacin and gentamicin than carbapenem-sensitive strains. In 2008, carbapenem-resistant strains additionally were more often resistant to ceftazidime, cefepime, aztreonam, piperacillin, and amikacin than carbapenem-sensitive strains. MBL-producing P. aeruginosa strains belonged more often to the O:11 serogroup than MBL-non-producing strains (51.7% vs. 34.3%, P<0.05). A greater percentage of non-MBL-producing strains had low MICs against ciprofloxacin and amikacin as compared with MBL-producing strains. CONCLUSIONS: The results of our study emphasize the need to restrict the spread of O:11 serogroup P. aeruginosa strains and usage of carbapenems to treat infections with P. aeruginosa in the intensive care units of our hospital.

Pseudomonas aeruginosa bacteremia: resistance to antibiotics, risk factors, and patient mortality.

UNLABELLED: The aim of our study was to determine the prevalence of Pseudomonas aeruginosa bacteremia, risk factors, and outcome of patients treated at the Hospital of Kaunas University of Medicine. MATERIAL AND METHODS: All hospitalized patients with blood culture positive for Pseudomonas aeruginosa during the 5-year period were included. A retrospective data analysis was performed to evaluate patients' risk factors and mortality caused by P. aeruginosa bacteremia. RESULTS: A total of 47 (58.8%) bacteremia episodes occurred in an intensive care unit (ICU). A primary source of bacteremia was identified in 50 (62.5%) episodes. Overall mortality rate was 58.8%. Univariate risk factors analysis showed the factors, which significantly increased the risk of death: mechanical ventilation (13.67 times, P<0.001), patient hospitalization in the ICU (8.51 times, P<0.001), acute respiratory failure (8.44 times, P<0.001), infection site in the respiratory tract (4.93 times, P=0.003), and central vein catheter (4.44 times, P=0.002). Timely and appropriate treatment and surgery were significant protective factors for 30-day mortality (11.1 and 5.26 times, respectively; P=0.001). Meropenem-resistant Pseudomonas aeruginosa strains caused bacteremia more frequently in patients older than 65 years than meropenem-sensitive strains (57.9%, n=11). All 19 patients with meropenem-resistant Pseudomonas aeruginosa bacteremia received inappropriate empirical antibiotic therapy. CONCLUSIONS: Treatment at the intensive care unit, mechanical ventilation, acute respiratory failure, source of infection in respiratory tract, and central vein catheter are the major risk factors associated with an increased mortality rate in patients with Pseudomonas aeruginosa bacteremia. The patients older than 65 years are at increased risk for bacteremia caused by carbapenem-resistant Pseudomonas aeruginosa strains. Carbapenems are not antibiotics of the choice of treatment for Pseudomonas aeruginosa bacteremia at the Hospital of Kaunas University of Medicine.

HLA class II alleles and haplotypes in Lithuanian children with type 1 diabetes and healthy children (HLA and type 1 diabetes).

OBJECTIVE: Type 1 diabetes mellitus is a slowly progressive autoimmune disease. The genetic background of type 1 diabetes mellitus is polygenic with the major disease locus located in the human leukocytes antigen (HLA) region. High risk and protective alleles, haplotypes, and genotypes have been determined in Lithuanian children with type 1 diabetes mellitus and healthy children. MATERIAL AND METHODS: In this case-control study, 124 children with diabetes (55 males and 69 females; mean age, 9.2±3.9 years) were tested for HLA class II and compared with 78 healthy controls (43 males and 35 females; mean age, 10.8±3.4 years; range, 0-15 years). HLA DRB1, DQA1, and DQB1 alleles were genotyped using a polymerase chain reaction. RESULTS: T1D risk-associated haplotypes (DR4)-DQA1*0301-DQB1*0302, (DR3)-DQA1*0501-DQB1*0201, and (DR1)-DQA1*0101-04-DQB1*0501 were more prevalent among children with diabetes than controls (50.0%, 41.1%, and 37.9% vs. 10.3%, 5.1%, and 24.4%, P<0.001). The haplotypes (DR4)-DQA1*0301-DQB1*0302 and (DR3)-DQA1*0501-DQB1*0201 increased T1D risk by 8.75 and 12.93 times, respectively (P<0.001). Protective haplotypes (DR2)-DQA1*0102-B1*0602, (DR11/12/13)-DQA1*05-DQB1*0301, and (DR13)-DQA1*0103-DQB1*0603 were significantly more prevalent among controls than children with diabetes (25.6%, 33.3%, 19.2% vs. 0%, 3.2%, 0%; P<0.001). These frequencies are quite similar to those from neighbor countries with varying incidence of type 1 diabetes mellitus. CONCLUSIONS: HLA class II haplotypes associated with type 1 diabetes mellitus positively or negatively were the same in Lithuanian children as in other European Caucasian populations. Differences in incidence and clinical manifestations of type 1 diabetes might be due to different environmental factors and/or lifestyle.