Increased expression of ubiquitin C-terminal hydrolase L1 in astrocytomas of ascending grades.

BACKGROUND: The ubiquitin-proteasome pathway controls the monitoring and degradation of important proteins and is involved in several cellular processes, such as development, differentiation, and transcriptional regulation. Recent evidence has shown that ubiquitin carboxy-terminal hydrolase-L1 (UCH-L1), a member of the deubiquitinating enzyme family that removes ubiquitin from protein substrates, is overexpressed in many types of cancer. AIM: This study thus examined the expression of UCH-L1 in human astrocytoma tissues. MATERIAL AND METHODS: Formalin-fixed, paraffin-embedded astrocytoma samples were obtained from 40 patients, after which histopathological examination, typing, and grading were performed. The study group included 10 histologically normal brain tissues, which served as the control group, and 10 WHO grade II, 10 WHO grade III, and 10 WHO grade IV (glioblastoma) samples. Normal brain tissue samples were obtained from the histologically normal, non-tumoral portion of the pathology specimens. UCH-L1 expression was evaluated using quantitative reverse transcription-polymerase chain reaction and immunohistochemistry. RESULTS: Astrocytoma tissues exhibited higher UCH-L1 expression compared to the control group. UCH-L1 overexpression increased significantly together with the increase in astrocytoma grades (from II to IV). CONCLUSION: UCH-L1 could be a good diagnostic and therapeutic marker for determining astrocytoma development and progression.

Seroprevalence of Toxoplasma gondii in Different Patient Groups in Our Hospital

Objective: Toxoplasma gondii (T. gondii) is an obligate intracellular parasite. It is regarded as an important cause of morbidity and mortality in congenital contamination and immunosuppressive patients. This study aimed to determine the seropositivity of T. gondii in various ages and patient groups, as well as to reveal the current immune status, especially in risk groups. Methods: Results of T. gondii serology conducted between 2015 and 2019 in the medical microbiology laboratory in a university hospital were retrospectively analyzed. In the study, anti-T. gondii IgM, anti-T. gondii IgG antibodies, and anti-T. gondii IgG avidity test results were investigated by the enzyme-linked fluorescent assay method. Additionally, seropositivity rates among immunosuppressed patients and pregnant women, which are risk groups for toxoplasmosis, were revealed. In the identification of the immunosuppressed patients, groups with significant immunosuppression were retrospectively determined by examining their files. Results: The serology of T. gondii was investigated in serum samples of a total of 20.875 individuals, among which 6.220 (29.8%) are males and 14.655 (70.2%) are females. Anti-T. gondii IgM and IgG positivity rates were significantly higher in women than in men. When all years are evaluated, IgM positivity in 16.448 patients and IgG positivity in 4.427 patients were investigated. In the 5-year period, T. gondii IgM seropositivity and T. gondii IgG seropositivity was among all the patients was 2.4% and 24.1%, respectively. While the rate of T. gondii IgG seropositivity in women of childbearing age was 36.1%, it was 42.4% in pregnant women and 14.6% in immunosuppressed patients. Conclusion: T. gondii serology follow-up of pregnant women and immunosuppressed patients in terms of reactivity of latent infection should be advised and toxoplasmosis should be considered in suspicious clinical cases.

Relationship between Selective IgA Deficiency and COVID-19 Prognosis.

The prevalence and mortality rates of coronavirus disease 2019 (COVID-19) widely vary among populations. Mucosal immunity is the first barrier to the pathogen's entry into the body. Immunoglobulin A (IgA) is the primary antibody responsible for mucosal immunity. We explored the relationship between selective IgA deficiency (SIgAD) and COVID-19 severity. We included 424 patients (203 women) with COVID-19. Eleven patients had SIgAD. Laboratory data of patients with SIgAD and normal IgA levels were compared. The relationship between SIgAD and severe COVID-19 infection was explored using logistic regression analysis. In the univariate logistic regression analysis, the risk of severe COVID-19 disease in patients with SIgAD was approximately 7.7-fold higher than that in other patients (odds ratio [OR], 7.789; 95% confidence interval [CI], 1.665-36.690, P = 0.008), while it was 4-fold (OR, 4.053; 95% CI, 1.182-13.903, P = 0.026) higher in the multivariate logistic regression analysis. Serum IgA levels were positively correlated with total lymphocyte counts and negatively correlated with C-reactive protein levels, which was a risk factor for severe COVID-19. In patients with SIgAD, the number of severe acute respiratory coronaviruses 2 that pass through mucosal membranes may be increased, leading to complications such as cytokine storm syndrome and acute respiratory distress syndrome.

Memory B cells and serum immunoglobulins are associated with disease severity and mortality in patients with COVID-19.

PURPOSE OF THE STUDY: The aim of this study was to investigate the relationship of B cell-mediated immunity with disease severity and mortality in patients with COVID-19. STUDY DESIGN: In this retrospective cohort and single-centre study, 208 patients with laboratory-confirmed COVID-19 were recruited. A COVID-19 severity score, ranging from 0 to 10, was used to evaluate associations between various factors. Serum immunoglobulin levels and the number of cells in B lymphocyte subsets were measured and their association with disease severity and mortality in patients with COVID-19 examined. RESULTS: The median age of the patients was 50 (35-63) years and 88 (42%) were female. The number of deceased patients was 17. The median COVID-19 severity score was 8 (6-8) in deceased patients and 1 (0-2) in survivors. Deceased patients had significantly lower levels of total B lymphocytes, naive B cells, switched memory B cells, and serum IgA, IgG, IgG1 and IgG2 than recovered patients (all p<0.05). In addition, a significant negative correlation was found between the number of these parameters and COVID-19 severity scores. Decrease in the number of total B cells and switched memory B cells as well as lower serum IgA, IgG and IgG1 levels were independent risk factors for mortality in patients with COVID-19. CONCLUSION: In the present study, the prognosis of patients with COVID-19 was shown to be associated with the B cell subset and serum immunoglobulin levels.

Meningitis recurrente por Streptococcus pneumoniae en una niña con un implante coclear y traumatismo craneoencefálico a pesar de haber recibido la vacuna neumocócica conjugada de 13 serotipos / Recurrent meningitis by Streptococcus pneumoniae in a girl with cochlear implant and head trauma despite 13-valent conjugated pneumococcal vaccine

La meningitis bacteriana recurrente es un fenómeno muy poco frecuente en los niños. Las fracturas de la base del cráneo y los implantes cocleares son factores predisponentes importantes, y el agente aislado con mayor frecuencia es el Streptococcus pneumoniae. La implementación de la vacuna neumocócica conjugada de 13 serotipos (VNC13) redujo la incidencia de enfermedades neumocócicas invasivas. La incidencia de enfermedades neumocócicas intercurrentes en pacientes vacunados suele estar relacionada con afecciones predisponentes preexistentes. En este artículo, presentamos un caso de meningitis neumocócica recurrente en una paciente con un implante coclear que sufrió un traumatismo craneoencefálico luego de haber recibido la vacunación completa con la VNC13. La paciente tuvo tres episodios de meningitis en el transcurso de un año. Se detectó la presencia de S. pneumoniae en el cultivo de líquido cefalorraquídeo (LCR) en el primer y tercer episodios, y mediante la prueba de reacción en cadena de la polimerasa (PCR, por su sigla en inglés) en el segundo episodio. Se realizó una intervención neuroquirúrgica luego del tercer episodio de meningitis, y la paciente no tuvo problemas de recurrencias durante los siguientes dos años. Hasta donde sabemos, en la bibliografía no se han descrito casos de meningitis de serotipo 1 por S. pneumoniae luego de la inmunización completa con PCV13.

Recurrent bacterial meningitis is a very rare phenomenon in children. Skull base fractures and cochlear implant are the important predisposing factors and, Streptococcus pneumoniae is the most frequently isolated agent. Implementation of 13-valent conjugated pneumococcal vaccine (PCV13) has reduced the occurence of invasive pneumococcal diseases. Vaccination breakthrough is typically related to underlying predisposing conditions. Herein, we reported recurrent pneumococcal meningitis in a patient with a cochlear implant who experienced a head trauma after being fully vaccinated with PCV13. The patient experienced three meningitis episodes within one year. S.pneumoniae was determined on CSF culture in the first and third episodes and detected by PCR at the second episode. Neurosurgical intervention was performed after the third meningitis episode, and the patient had no recurrence problems for the following two years. To our knowledge, breakthrough S.pneumoniae serotype 1 meningitis after full PCV13 immunization has not been reported elsewhere in the literature.

Recurrent meningitis by Streptococcus pneumoniae in a girl with cochlear implant and head trauma despite 13-valent conjugated pneumococcal vaccine. / Meningitis recurrente por Streptococcus pneumoniae en una niña con un implante coclear y traumatismo craneoencefálico a pesar de haber recibido la vacuna neumocócica conjugada de 13 serotipos.

Recurrent bacterial meningitis is a very rare phenomenon in children. Skull base fractures and cochlear implant are the important predisposing factors and, Streptococcus pneumoniae is the most frequently isolated agent. Implementation of 13-valent conjugated pneumococcal vaccine (PCV13) has reduced the occurence of invasive pneumococcal diseases. Vaccination breakthrough is typically related to underlying predisposing conditions. Herein, we reported recurrent pneumococcal meningitis in a patient with a cochlear implant who experienced a head trauma after being fully vaccinated with PCV13. The patient experienced three meningitis episodes within one year. S.pneumoniae was determined on CSF culture in the first and third episodes and detected by PCR at the second episode. Neurosurgical intervention was performed after the third meningitis episode, and the patient had no recurrence problems for the following two years. To our knowledge, breakthrough S.pneumoniae serotype 1 meningitis after full PCV13 immunization has not been reported elsewhere in the literature.

La meningitis bacteriana recurrente es un fenómeno muy poco frecuente en los niños. Las fracturas de la base del cráneo y los implantes cocleares son factores predisponentes importantes, y el agente aislado con mayor frecuencia es el Streptococcus pneumoniae. La implementación de la vacuna neumocócica conjugada de 13 serotipos (VNC13) redujo la incidencia de enfermedades neumocócicas invasivas. La incidencia de enfermedades neumocócicas intercurrentes en pacientes vacunados suele estar relacionada con afecciones predisponentes preexistentes. En este artículo, presentamos un caso de meningitis neumocócica recurrente en una paciente con un implante coclear que sufrió un traumatismo craneoencefálico luego de haber recibido la vacunación completa con la VNC13. La paciente tuvo tres episodios de meningitis en el transcurso de un año. Se detectó la presencia de S. pneumoniae en el cultivo de líquido cefalorraquídeo (LCR) en el primer y tercer episodios, y mediante la prueba de reacción en cadena de la polimerasa (PCR, por su sigla en inglés) en el segundo episodio. Se realizó una intervención neuroquirúrgica luego del tercer episodio de meningitis, y la paciente no tuvo problemas de recurrencias durante los siguientes dos años. Hasta donde sabemos, en la bibliografía no se han descrito casos de meningitis de serotipo 1 por S. pneumoniae luego de la inmunización completa con PCV13.

New Clues in the Malignant Progression of Glioblastoma: Can the Thioredoxin System Play a Role?

AIM: To evaluate and compare the expression of thioredoxin reductase 1 (TrxR1) in primary and secondary glioblastoma samples. MATERIAL AND METHODS: Surgically resected human glioblastoma samples from 40 patients who underwent surgery at our institution were extracted from their histopathological specimens and divided into three groups. Ten histopathologically regular cerebral tissue samples, acquired from the non-neoplastic portion of the specimens, were assigned as the control group. Twenty specimens that included tumoral tissue from each type of glioblastoma (WHO grade IV, primary and secondary) were assigned as the primary and secondary glioblastoma groups. TrxR1 expression was analyzed by using both quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. Isocitrate dehydrogenase 1 (IDH1) mutation was analyzed by immunohistochemistry. Ki-67 proliferative index and apoptosis were also analyzed by immunohistochemistry. The differences between the groups were statistically compared and the correlation between these parameters was analyzed. RESULTS: The expressions of TrxR1 and Ki-67 values were significantly higher in primary glioblastoma. IDH1 mutation was significantly higher in secondary glioblastoma. TrxR1 expression was found to be highly correlated with the Ki-67 index. The apoptotic index was similar between primary and secondary glioblastoma. CONCLUSION: This study showed a high TrxR1 expression in primary glioblastoma which could indicate a role of the Trx system in promoting the malignant progression by some complex processes.

Telmisartan ameliorates oxidative stress and subarachnoid haemorrhage-induced cerebral vasospasm.

OBJECTIVES: Growing evidence suggests that oxidative stress is one of the factors contributing to subarachnoid haemorrhage (SAH)-induced cerebral vasospasm. SAH-induced cerebral vasospam alters thioredoxin (Trx) cycle enzymes and thioredoxin-interacting protein (TXNIP) as an important endogenous antioxidant system. In this study, we have explored the effects of telmisartan on the vascular morphological changes, endothelial apoptosis, tissue oxidative stress status and the level of Trx cycle enzymes/ TXNIP in a rabbit SAH model. METHODS: Forty male New Zealand rabbits were randomly divided into five groups of eight rabbits each: control group, sham group, SAH group, SAH + vehicle group and SAH + telmisartan group. SAH was created by a single cisterna magna blood injection. SAH + telmisartan group received telmisartan treatment (5 mg/kg intraperitoneal, once daily) for 72 h. The brainstem tissue Trx1, Trx2, Trx reductase (TrxR), TrxR1and TXNIP levels were investigated. Total oxidant status (TOS), total antioxidant status (TAS), malondialdehyde (MDA) levels and tumour necrosis factor alpha (TNF alpha) levels were investigated. Basilar artery segments were investigated for cross-sectional area, wall thickness measurements and endothelial apoptosis. RESULTS: Telmisartan treatment restored the lowered level of Trx1, TrxR, TAS and the expression of TrxR1 seen in SAH. Telmisartan treatment also decreased TXNIP expression, TOS, MDA and TNF alpha levels. Morphological changes of cerebral vasospasm were attenuated after treatment. Endothelial apoptosis significantly reduced. DISCUSSION: Treatment with telmisartan ameliorates oxidative stress and SAH-induced cerebral vasospasm in rabbits. These effects of telmisartan may be associated with downregulation of TXNIP and upregulation of Trx/TrxR.

A novel modified PAIR technique using a trocar catheter for percutaneous treatment of liver hydatid cysts: a six-year experience.

PURPOSE: We aimed to demonstrate the success and reliability of a novel puncture, aspiration, injection, and reaspiration (PAIR) technique in liver hydatid cysts. METHODS: Percutaneous treatment with ultrasonographic guidance was performed in 493 hepatic hydatid cysts in 374 patients. Patients were treated with a new PAIR technique by single puncture method using a 6F trocar catheter. The results of this novel technique were evaluated with regards to efficacy and safety of the procedure and complication rates. RESULTS: Out of 493 cysts, 317 were Gharbi type I (WHO CE 1) and 176 were Gharbi type II (WHO CE 3A). Of all cysts, 13 were referred to surgery because of cystobiliary fistulization. Recurrence was observed in 11 cysts one month later. Therefore, the success rate of the PAIR technique was 97.7% (469/480). Minor complications (fever, urticaria-like reactions, biliary fistula) were seen in 44 treated patients (12%, 44/374); the only major complication was reversible anaphylactic shock which was observed in two patients (0.5%, 2/374). CONCLUSION: This novel modified PAIR technique may be superior to catheterization by Seldinger technique due to its efficiency, easier application, lower severe complication rate, and lower cost. Further comparative studies are required to confirm our observations.

High thioredoxin reductase 1 expression in meningiomas undergoing malignant progression.

Thioredoxin (Trx) is a redox active protein that regulates several physiological and biochemical functions, such as growth, apoptosis and cellular defense. The function of Trx itself is regulated by thioredoxin reductase (TrxR). This study was designed to determine the expression of TrxR1 in meningioma tissues of different World Health Organization grades (grade I-III). Meningioma tissues were extracted from the histopathological specimens of 29 patients. These samples included seven histologically normal meningeal tissues that served as a control group and 12 grade I, 12 grade II and 5 grade III meningioma samples. TrxR1 expression was evaluated using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunostaining. The proliferative and apoptotic indices of the specimens were investigated by Ki-67 immunostaining and TUNEL assay, respectively. TrxR1 expression, as assessed by qRT-PCR, increased significantly with meningioma grade (p < 0.001). The immunostaining intensity of TrxR1 increased significantly with meningioma grade (p < 0.001). Ki-67 index values increased significantly in accordance with grade progression (p < 0.001). The apoptotic index values were not significantly different in any group (p > 0.05). Trx system seems to be involved in the malignant progression of meningiomas. Further, large studies are required to elucidate the exact role of this system.

Tissue thioredoxin reductase-1 expression in astrocytomas of different grades.

Thioredoxin (Trx) is a redox active protein that regulates several physiological and biochemical functions, such as growth, apoptosis and cellular defense. The function of Trx itself is regulated by thioredoxin reductase (TrxR). Studies performed in a variety of human primary tumors have shown that thioredoxin reductase 1 (TrxR1) is overexpressed in tumoral tissues compared with corresponding normal tissues. This study was designed to determine the expression of TrxR1 in astrocytoma tissues of different World Health Organization (WHO) grades (grade I-IV). The proliferative (Ki-67) and apoptotic indices of the specimens were also investigated for correlation analysis. Astrocytoma tissues were extracted from the histopathological specimens of 40 patients. These samples included seven histologically normal brain tissues that served as a control group and ten tumoral samples for each grade of astrocytoma (grade I-IV). The histologically normal brain tissues were obtained from the non-tumoral portions of the pathological specimens of grade I (2 cases), grade II (2 cases), grade III (2 cases) and grade IV (1 case) astrocytomas. TrxR1 expression was evaluated using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunostaining. The proliferative and apoptotic indices of the specimens were investigated by Ki-67 immunostaining and TUNEL assay, respectively. TrxR1 expression, as assessed by qRT-PCR, increased significantly with astrocytoma grade (p = 0.01). The immunostaining intensity of TrxR1 in grade IV astrocytomas was significantly greater than that in the control tissue and all other astrocytoma grades (p < 0.001). Similarly, immunostaining intensity of TrxR1 in the grade III astrocytomas was significantly greater than that in the control group and grade I astrocytomas (p < 0.001). All astrocytoma tissues showed more intense staining in ascending grades, but the differences between grade I and the control, grade II and the control, grades II and I, grades III and II were not statistically significant (p > 0.05). Ki-67 index values increased significant in accordance with grade progression (p = 0.01). The apoptotic index values were not significantly different in any group (p > 0.05); however, the differences between grade IV and the control and between grades IV and I were statistically significant (p < 0.05). Expression of TrxR1, as assessed by both qRT-PCR and immunostaining, correlated highly with both the astrocytoma grade and Ki-67 index.

The presence of Torque teno virus in chronic obstructive pulmonary disease.

Torque Teno Virus (TTV) has been identified as transfusion-transmitted virus in humans, initially. Although TTV viremia is extremely common in the general population worldwide, there is no direct causal evidence linking TTV infection to specific clinical manifestations. Our hypothesis was that TTV might play a role in Chronic obstructive pulmonary disease (COPD) by inducing inflammatory mechanisms previously identified. The study was conducted on 57 COPD patients and 39 healthy control groups. COPD patient groups included: the patients (n:20) with exacerbation needed noninvasive ventilation, the patients (n:19) who received only medical treatment, and the invited patients (n:18) for outpatient control. Serum samples were collected from patients and voluntary blood donors. TTV DNA quantification was carried out with a real time PCR by the hybridization probe system and viral load was interpreted through the crossing point value. TTV DNA was detected in the majority of both patients and healthy control groups. The prevalence was 94.4% (17/18) in patients for outpatient control, 94.7% (18/19) in patients who received only medical treatment, 100% (20/20) in patients with exacerbation needed noninvasive ventilation and 84.6% (33/39) in healthy controls. This difference was not statistically significant. However, CP values was statistically different in all the patient groups from the control group. TTV DNA prevalence was higher in patients than healthy individuals. More interesting thing, viral load was highest in the patients with exacerbation needed noninvasive ventilation. As a result, TTV may be associated with COPD and the severity of it.

Comparison of the performance of TK system with LJ and MGIT methods in the diagnosis of tuberculosis.

Tuberculosis is a common infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis (TB). Various liquid or solid media are used for the diagnosis of tuberculosis. TK Rapid Mycobacterial Culture System has been developed recently. In our study, we aimed to compare TK Rapid Mycobacterial Culture System with LJ and MGIT systems in the diagnosis of tuberculosis. 200 clinical specimens (152 sputum, 41 Bronchoalveolar lavage fluid (BAL), 4 gastric aspirations, 2 urine and 1 wound) obtained from 192 patients from different clinics were included for the diagnosis of TB. All specimens were decontaminated by using the same-common procedure in all the methods. The obtained sediment was used for inoculation for the BACTEC MGIT 960, TK and LJ. Additionally, smears were prepared from the residual suspension for Ehrlich-Ziehl-Neelsen (EZN) staining for microscopic examination. Contamination was observed in 23 sputum and 4 BAL samples. Contamination rates for TK, LJ, and BACTEC MGIT 960 systems were determined as 3 (1.5%), 13 (6.5%), and 18 (9%) respectively. Mycobacterium tuberculosis growth was determined as 15 (7.5%), 14 (7%) and 13 (6.5%) by TK culture system, MGIT and LJ, respectively. In our study, the total mean detection times of Mycobacterium tuberculosis by the LJ, TK, and MGIT method were 20.1, 17.1, and 8.3 days, respectively. TK system showed a dramatically lower contamination rate than the others. There was no difference in growth rates for each of the three methods. We concluded that the TK culture system is disadvantageous in terms of turnaround time.

A rare cause of bacteremia in a pediatric patient with Down syndrome: Sphingomonas paucimobilis.

Sphingomonas paucimobilis, is a yellow-pigmented, aerobic, non fermentative, gram negative motile bacillus. S. paucimobilis which is widely found in nature and hospital environments rarely cause serious or life threatening infections. In this report, a case of hospital acquired bloodstream infection due to S. paucimobilis in a patient with Down syndrome who was on treatment for presumed pneumonia is presented. A one year-old child patient who was a known case of Down syndrome and had previously experienced cardiac surgery was hospitalized and treated for pneumonia. On the 12th day of hospitalization, blood cultures were taken because of a high body temperature. One of the blood cultures was positive for gram-negative rods. After 48 hour of incubation, the sub-cultures on blood agar medium yielded pure growth of a yellow, non-fermentative, gram-negative, rod-shaped bacterium. The microorganism was positive for oxidase, and esculin hydrolysis, while negative for urea and nitrate reduction, citrate utilisation and motility. The isolate had been identified as S. paucimobilis by using Vitek 2 system. The antibiotic susceptibility test was also performed with the same system and the strain was found to be susceptible to piperacillin-tazobactam and other antibiotics. Treatment with intravenous piperacilin-tazobactam (150 mg/kg/day) was initiated. He responded well to the treatment and was discharged after 10 days. This case is reported to emphasize that S. paucimobilis should be kept in mind as a nosocomial infectious agent in patients with Down syndrome and immunosuppressive patients and the infections should be treated according to the sensitivity test results.

A comparison of immuncapture agglutination and ELISA methods in serological diagnosis of brucellosis.

BACKGROUND: Different serological tests are used in serologic diagnosis of brucellosis. The most widely used of these are Standard Tube Agglutination and Coombs anti-brucella tests. Whereas ELISA Ig M and Ig G tests have been in use for a long time, immuncapture agglutination test has been recently introduced and used in serological diagnosis. The aim of this study was to compare diagnostic values of ELISA Ig M and Ig G and immuncapture agglutination tests with Coombs anti-brucella test. METHODS: Sera from 200 patients with presumptive diagnosis of brucellosis were included into the study. Coombs anti-brucella test, ELISA Ig M and Ig G tests and Immuncapture test were investigated in these sera. Then, sensitivity, specificity, negative predictive and positive predictive values were calculated. RESULTS: Sensitivity, specificity, negative predictive and positive predictive values were found to be 90.6%, 76.3%, 94.2%, and 65.9% respectively for the Immuncapture test, whereas they were found to be 73.7%, 58.9%, 84.2%, and 42.8% for Ig G and 72.2%, 67.8%, 85.2%, and 48.7% for Ig M. The Immuncapture test was found to be compatible with ELISA Ig M and Ig G tests but it was statistically incompatible with Coombs anti-brucella test. CONCLUSIONS: Immuncapture agglutination test yields similar results to those of Coombs anti-brucella test. This test is a useful test by virtue of the fact that it determines blocking antibodies in the diagnosis and follow-up of brucellosis.

[Investigation of microbial colonization of computer keyboards used inside and outside hospital environments]. / Hastane ve hastane disi ortamlarda kullanilan bilgisayarlarin klavyelerinde mikrobiyal kolonizasyonun arastirilmasi.

Computers have been commonly used in daily life and at hospitals by medical staff. This study was carried out to search the microbial colonization of computer keyboards and mice used inside and outside hospital environments. Keyboards and mice samples from a total of 398 computers were included to the study, in which 38 were used by doctors and nurses in the hospital clinics (Group 1); 32 by the medical faculty students (Group 2), and 328 by university students (Group 3) in the computer laboratories of Selcuk University, Konya (located at middle Anatolia). Of the computers, 96.7% (n:385) have been found to be colonized by coagulase-negative staphylococci (CONS), 13.1% (n:52) by gram-positive spore-forming bacilli and 8.8% (n:35) by corynebacteria; followed by Candida spp. (4.2%), gram-negative bacilli (1.7%) [Acinetobacter spp. (n:4), Pseudomonas sp. (n:l), Klebsiella sp. (n:l), E. coli (n:1)], Staphylococcus aureus (1.5%), and molds (Penicillium, Aspergillus; 1.2%). The isolation rates of CoNS were similar between the groups (94,7%, 93.7%, and 97.2%, respectively). However it was noted that all of the gram-negative bacterial isolates (7/38; 18.4%) were from the samples collected from hospital computers (Group 1). Susceptibility rates of CoNS isolates to cefoxitin were detected as 26.2% in Group 1, 79.2% in Group 2, and 91.3% in Group 3. Five out of six S. aureus strains were found susceptible to cefoxitin, except one isolated from a sample of Group 1. Linezolid resistance in both CoNS and S. aureus isolates were not determined in any groups. As a result, according to the data obtained from this study as well as from the other foreign studies, the computer keyboards and mice which are widely used in the hospital settings, are being the source of potential cross contamination in the development of nosocomial infections. Therefore the computers should be cleaned properly frequently and hand washing procedures and disinfection rules should be obeyed after the use of computers before handling the patients.