Analysis of 5-year hospitalization data of patients with systemic lupus erythematosus: Damage is a risk factor for frequent and longer stays.

OBJECTIVE: The annual hospitalization rate of patients with systemic lupus erythematosus (SLE) is approximately 10%, and hospitalizations are responsible for most of the healthcare expenses. Herein, we analyzed 5-year hospitalization data of SLE patients and determined factors leading to hospitalization. METHODS: Clinical, laboratory, and hospitalization data of SLE patients admitted to our rheumatology clinic in 2015-2020 were retrieved from our SLE database and analyzed. SLICC SLE damage index (SDI) and disease activity at admission (SLEDAI-2K) were determined. RESULTS: Among 161 hospitalized patients, 86% were females. Total rheumatologic hospitalization number was 298, and 38% of the patients were hospitalized more than once (1.85 ± 1.56). The mean hospitalization duration covering all stays for each patient was 25 ± 26.5 days. Active disease, infection, and damage-related complications were first three causes of hospitalization. Compared to patients hospitalized for active disease or damage, patients hospitalized for infection had a significantly higher number of readmissions (p < .05) and their total hospital stay was longer (p < .01).The frequency of patients with damage and the mean SDI score was significantly lower in the active disease group (68%, 1.93 ± 2.05) than hospitalizations for infection (90%, 2.68 ± 1.63) and damage-related causes (96%, 3.04 ± 1.65) (p < .05). The mean SDI score and duration (r = 0.551, p < .001) and the number of hospitalizations (r = 0.393, p < .001) were positively correlated. The mean disease activity scores of patients hospitalized for active disease, infection, and damage-related reasons were 11.03 ± 6.08, 3.21 ± 2.80, and 2.96 ± 3.32, respectively (p < .001). Renal active disease was the most common (44%), followed by hematological (34.8%), articular (21.7%), and mucocutaneous (21%) activity.Ten percent of the patients all of whom had damage were admitted to intensive care unit (ICU). Total hospitalization duration, mean SDI, antiphospholipid syndrome, lupus anticoagulant, thrombocytopenia, serositis, pulmonary hypertension, history of alveolar hemorrhage, and cardiac valve involvement were associated with ICU admission (p < .05 for all). CONCLUSION: Disease activity, infections, and damage are the leading causes of hospitalization in SLE patients. Damage prolongs hospital stay and increases hospitalization rate and ICU need. Tight control of disease activity with rational use of immunosuppressive treatment is important to reduce damage and hospitalizations.

The correlation between pregnancy, disease activity and adverse pregnancy outcomes in patients with systemic lupus erythematosus.

OBJECTIVE: In this study, our pregnant systemic lupus erythematosus (SLE) cohort, which was under medical surveillance of both our Rheumatology and Obstetrics departments, was analyzed. We intended to determine the effects of pregnancy on disease activity and the correlation between disease flares and adverse pregnancy outcomes. METHODS: One hundred sixty eight pregnancy data involving 136 patients with SLE were examined. Cumulative clinical, laboratory, and serological parameters were described. Disease activity and flares were calculated using the systemic lupus erythematosus disease activity index 2000 (SLEDAI-2K) in the pre/postpartum periods and the SLEPDAI in the three trimesters of pregnancy. Patients with a SLEDAI-2K or SLEPDAI ≥ 4 were classified as "active." Patients with lupus low disease activity state (LLDAS) during each of these periods were identified.Fetal/neonatal death, premature birth due to pre-eclampsia, eclampsia or hemolysis, elevated Liver enzymes (HELLP) syndrome, and neonates small for gestational age were determined as adverse pregnancy outcomes (APO). RESULTS: Out of 168 pregnancies, there were 60 (35.7%) pregnancies with flares covering the pregnancy and 6 months of postpartum period. The mean SLEDAI in the 6 months postpartum period was significantly higher compared to mean disease activity during pregnancy (p < .05). Of all pregnancies, 132 (78.6%) were in LLDAS during pregnancy. Comparison of the frequency of severe postpartum flares in patients who were in LLDAS during pregnancy revealed a lower percentage of flares compared to those who were not in the LLDAS group (11 vs 29%, p < .05). APO was observed in 33.9% of 168 pregnancies. The mean SLEPDAI score was significantly higher in APO+ pregnancies than in APO- pregnancies (4.9 ± 6.1 vs 2.8 ± 4.9, p = .002). Comparison of SLICC damage score between APO - and + pregnancies revealed a significantly higher score in APO+ pregnancies (1.8 ± 2.1 vs 0.8 ± 1.3, p = .001). CONCLUSION: Postpartum six-month period appears to have the highest risk for disease flares during SLE pregnancies. Disease activity during pregnancy increases the risk of APO. In order to achieve a positive pregnancy outcome and lower maternal morbidity, regular follow-up of patients is necessary.

Criteria for Hyperinflammation Developing in COVID-19: Analysis of 2 Cohorts From Different Periods of the Pandemic.

OBJECTIVE: Hyperinflammation (HI) that develops in week 2 of COVID-19 contributes to a worse outcome. Because week 2 laboratory findings can be relatively mild, the available criteria for classification of hemophagocytic lymphohistiocytosis or macrophage activation syndrome are not helpful. METHODS: Our study included a discovery cohort of patients from Turkey with symptomatic COVID-19 who were followed up while hospitalized during the initial wave and a replication cohort of hospitalized patients from a later period, all of whom required oxygen support and received glucocorticoids. Diagnosis of HI was made by an expert panel; most patients with COVID-19-associated HI (HIC) received tocilizumab or anakinra. Clinical and laboratory data from start day of treatment with tocilizumab or anakinra in HIC patients were compared with the data from day 5-6 in patients without HIC. Values maximizing the sensitivity and specificity of each parameter were calculated to determine criteria items. RESULTS: The discovery cohort included 685 patients, and the replication cohort included 156 patients, with 150 and 61 patients receiving treatment for HI, respectively. Mortality rate in HI patients in the discovery cohort (23.3%) was higher than the rate in patients without HI (3.7%) and the rate in patients in the overall replication cohort (10.3%). The 12-item criteria that we developed for HIC showed that a score of 35 provided 85.3% sensitivity and 81.7% specificity for identification of HIC. In the replication cohort, the same criteria resulted in 90.0% sensitivity for HIC; however, lower specificity values were observed because of the inclusion of milder cases of HIC responding only to glucocorticoids. CONCLUSION: The use of the 12-item criteria for HIC can better define patients with HIC with reasonable sensitivity and specificity and enables an earlier treatment start.

Performances of different classification criteria for systemic lupus erythematosus in a single-center cohort from Turkey.

OBJECTIVE: Sensitivity and specificity of SLE classification criteria may vary in different populations and clinical settings. In this study, we aimed to compare the performances of three criteria sets/rules (1997, 2012, and 2019) in a large cohort of patients and relevant diseased controls. METHODS: The medical records of consecutive SLE patients and diseased controls were reviewed for clinical and laboratory features relevant to all sets of criteria. Criteria sets/rules were analyzed based on sensitivity, positive predictive value, specificity, and negative predictive value, using clinical diagnosis with at least 6 months of follow-up as the gold standard. A subgroup analysis was performed in ANA positive patients. RESULTS: A total of 393 SLE patients and 308 non-SLE diseased controls were included. Sensitivity was 78.4% for 1997 criteria and was more than 90% for both 2012 (91.9%) and 2019 (94.4%) criteria. Specificity was the highest (95.1%) for 1997 ACR criteria, 91.5% for 2012 SLICC criteria and 91.2% for 2019 EULAR/ACR criteria. When only ANA positive patients were analyzed, sensitivity of each criteria increased by 1%, 0.8%, and 2.2%, respectively. Specificity of 1997 criteria decreased by 2% and specificity of 2012 and 2019 criteria both decreased to less than 90%. CONCLUSION: EULAR/ACR criteria were more sensitive than 1997 criteria and had a comparable performance with SLICC criteria. When only ANA positive patients were analyzed, the presence of false positive results (originated from patients with Sjögren's disease and antiphospholipid syndrome mainly) decreased the specificity of both SLICC and EULAR/ACR criteria.

Description of damage in different clusters of patients with antiphospholipid syndrome.

OBJECTIVE: To identify the different clinical phenotypes of antiphospholipid syndrome (APS) by using cluster analysis and describe cumulative damage of disease clusters. METHODS: This retrospective study includes patients with APS (±systemic lupus erythematosus (SLE)). Two-step cluster analysis was applied by considering clinical data. Damage was calculated for all patients by applying damage index for APS (DIAPS). RESULTS: A total of 237 patients (198 females; median age of 43 years; median follow-up of 9.5 years) were classified into four clusters. Cluster 1 (n = 74) consisted of older patients with arterial-predominant thrombosis, livedo reticularis, and increased cardiovascular risk; cluster 2 (n = 70) of SLE+APS patients with thrombocytopenia and heart valve disease; cluster 3 (n = 59) of patients with venous-predominant thrombosis, less extra-criteria manifestations; and cluster 4 (n = 34) of patients with only pregnancy morbidity with lower frequency of extra-criteria features and cardiovascular risk. Patients with SLE+APS (n = 123) had the highest mean DIAPS. Regarding clusters, 1 and 2 had high cumulative damage. While cumulative survival rates of clusters did not differ, cluster 2 and 3 had lower survival rates at further years. There was no correlation between DIAPS and mortality. CONCLUSION: SLE+APS patients with extra-criteria manifestations and older APS patients with arterial thrombosis and increased cardiovascular risk have higher cumulative damage. Effective treatment of SLE disease activity and control of cardiovascular risk may help to reduce cumulative damage in these patients.

Mortality-associated factors of candidemia: a multi-center prospective cohort in Turkey.

Candidemia may present as severe and life-threatening infections and is associated with a high mortality rate. This study aimed to evaluate the risk factors associated with 30-day mortality in patients with candidemia. A multi-center prospective observational study was conducted in seven university hospitals in six provinces in the western part of Turkey. Patient data were collected with a structured form between January 2018 and April 2019. In total, 425 episodes of candidemia were observed during the study period. Two hundred forty-one patients died within 30 days, and the 30-day crude mortality rate was 56.7%. Multivariable analysis found that SOFA score (OR: 1.28, CI: 1.154-1.420, p < 0.001), parenteral nutrition (OR: 3.9, CI: 1.752-8.810, p = 0.001), previous antibacterial treatment (OR: 9.32, CI: 1.634-53.744, p = 0.012), newly developed renal failure after candidemia (OR: 2.7, CI: 1.079-6.761, p = 0.034), and newly developed thrombocytopenia after candidemia (OR: 2.6, CI: 1. 057-6.439, p = 0.038) were significantly associated with 30-day mortality. Central venous catheter removal was the only factor protective against mortality (OR: 0.34, CI:0.147-0.768, p = 0.010) in multivariable analysis. Candidemia mortality is high in patients with high SOFA scores, those receiving TPN therapy, and those who previously received antibacterial therapy. Renal failure and thrombocytopenia developing after candidemia should be followed carefully in patients. Antifungal therapy and removing the central venous catheter are essential in the management of candidemia.

Symptomatic osteonecrosis of the hip and knee in patients with systemic lupus erythematosus: Prevalence, pattern, and comparison of natural course.

OBJECTIVE: Osteonecrosis (ON), also known as avascular necrosis, is characterized by the collapse of the architectural bone structure secondary to the death of the bone marrow and trabecular bone. Osteonecrosis may accompany many conditions, especially rheumatic diseases. Among rheumatic diseases, osteonecrosis is most commonly associated with systemic lupus erythematosus (SLE). We assessed prevalence and distribution pattern of symptomatic ON in patients with SLE and compare the natural courses of hip and knee ON. METHODS: 912 SLE patients admitted between 1981 and 2012 were reviewed. SLE patients with symptomatic ON were retrospectively identified both from the existing SLE/APS database. The prevalence of symptomatic ON was calculated; with ON, the joint involvement pattern was determined by examining the distribution of the joints involved, and then the data about the hip and knee joints were entered in the Kaplan-Meier analysis. Kaplan-Meier methods were used to calculate 5- and 10-year rates of ON-related hip (the hip group) and knee survival (the knee group). RESULTS: Symptomatic ON developed in various joints in 97 of 912 patients with SLE, and the overall prevalence of ON was detected as 10.6%. The mean age at the time of SLE and ON diagnoses were 27.9 ± 9.9 (14-53) and 34.2 ± 11.3 (16-62) years, respectively. The mean duration from diagnosis of SLE to the first development of ON was 70.7± 60.2 (range = 0-216) months. The most common site for symptomatic ON was the hips (68%, n=66), followed by the knees (38%, n = 37). According to Kaplan-Meier analysis, hip and knee joint survival rates associated with 5-year ON were 51% and 88%, and 10-year survival rates were 43% and 84%, respectively. CONCLUSION: We observed that the prevalence of symptomatic ON in patients with SLE was 10.6%. With the estimated 10-year survival rates of 40% versus 84% for the hip and knee joints, respectively, hip involvement may demonstrate a more aggressive course to end-stage osteoarthritis than the knee involvement.

Comparison of the effectiveness of caspofungin and liposomal amphotericin-B for the treatment of C. tropicalis-induced peritonitis in mice.

In order to compare the effectiveness of liposomal amphotericin B (LAB) and caspofungin monotherapy in Candida tropicalis-induced peritonitis in an experimental mice model 56 healthy male BALB/c mice (10-12 weeks; 20-25 g) were divided into groups and C. tropicalis strains were intraperitoneally (IP) inoculated into mice groups except the control group. After the injection, three doses of LAB (0.5, 1.0, 2.0 mg/kg/day) and caspofungin (1.0, 2.0, 5.0 mg/kg/day) were administered to groups for five consecutive days, starting 48-h post-infection. The mice were then followed up for 14 days and killed by cervical dislocation. When their peritoneal fluid was examined, the difference in fungal growth between the treatment group and control group was significant (p <0.05). Evaluation of the treatment groups revealed that fungal growth decreased with increasing dose of the antifungal agent (p >0.05). There was no dose-related difference from mice which received LAB or those which received caspofungin in our experimental model. During our study, no death was detected despite the similar injection doses compared with other studies using Candida species. The results of this study suggest that C. tropicalis could have lower virulence, perhaps limited by natural immunity, and causes mortality at much higher doses.

Imported Malaria in Turkey: The Importance of Diagnosis and Treatment of Plasmodium falciparum/Plasmodium vivax Mixed Infection.

The most common types of malaria in the world are Plasmodium vivax and P. falciparum. In countries where both species are endemic, P. vivax and P. falciparum coinfection also occurs. Thus, the possibility of mixed malaria in Turkey should always be considered in cases with a traveling history to these countries. Here, we report a case of P. vivax/P. falciparum mixed infection that was diagnosed as P. falciparum malaria in Ethiopia. However, the administered treatment was inadequate, and infection recurred because of the miss in the diagnosis of P. vivax malaria, for which an effective drug for hypnozoites was not administered. This case report emphasizes the importance of diagnosis, correct and adequate treatment of infections, and a close follow-up of diseases.

Effects of Web-Based Educational Intervention on Self-Management in Kidney Recipients.

Information technology and the Internet are rapidly becoming effective tools for teaching. Selfmanagement skills are important for adaptation and long-term survival in kidney recipients. Web-based training may help patients develop self-management skills through information access. This literature review aimed to determine the effects of Web-based educational intervention on self-management in kidney recipients. The Internet supports effective health education intervention strategies by providing a learning environment that is always available. Medicine management, routine follow-up, awareness of the signs and symptoms of rejection, infection prevention, self-monitoring, physical activity, and nutrition are important during the posttransplant period. Another important component of achievement in related matters is the competence of individuals with their own self-management. Webbased training is beneficial for appointment follow-up, nutritional adaptation, and treatment of anxiety and depression. Web-based training allows kidney recipients to access information at any time and place; this information promotes proper self-management.

Colistin efficacy in the treatment of multidrug-resistant and extremelydrug-resistant gram-negative bacterial infections.

BACKGROUND/AIM: Colistin is used as a salvage therapy for multidrug-resistant and extremely drug-resistant gram-negative bacterial infections. Our aim was to evaluate colistin efficiency and toxicity in the treatment of these resistant gram-negative bacterial infections. MATERIALS AND METHODS: This is a retrospective study carried out in a tertiary care hospital during 2011-2013. Study data were collected from the medical records and consultations of the infectious diseases clinic. RESULTS: The study group included 158 patients with nosocomial infections and 136 (86.1%) of them were hospitalized in the ICU. Respiratory tract infections were the most commonly observed ones (n = 103, 65.2%). The most frequently isolated microorganism was Acinetobacter baumannii (72.2%). A total of 98 (62.0%) patients had clinical cure. There was no statistically significant difference between monotherapy (n = 3/6, 50.0%) and combination therapies (n = 95/152, 62.5%) according to clinical response. Underlying ultimately fatal disease, previous renal disease, and total parenteral nutrition were independent risk factors for poor clinical response. Nephrotoxicity developed in 80 (50.6%) patients and clinical cure was statistically unrelated with nephrotoxicity. CONCLUSION: Colistin may be used as an effective agent for multidrug-resistant and extremely drug-resistant gram-negative bacterial infections with close monitoring of renal functions, especially for older and critically ill patients.

Evaluation of patients with zygomycosis.

AIM: Zygomycosis is a severe angioinvasive infection caused by Zygomycetes. We retrospectively investigated 16 cases of zygomycosis. MATERIALS AND METHODS: The data of patients, who had been followed between 2004 and 2010 in 8 tertiary-care teaching hospitals, were reviewed. Demographic characteristics, underlying diseases, and clinical signs and symptoms of the patients, as well as diagnostic methods, data obtained by radiological imaging methods, and the therapies, were recorded. Therapeutic approaches, antifungal agents and duration of use, and the characteristics of the cases were identified. RESULTS: The study included 11 female and 5 male subjects. The most common symptoms and clinical signs were fever (n = 9) and retro- orbital pain (n = 7). Rhinocerebral zygomycosis was the most common form. The mean time elapsed for diagnosis was 14.26 + 13.96 (range: 2-52) days. Antifungal therapy was given to 15 patients (94%). In addition to antifungal therapy, 12 patients underwent surgical intervention 1 to 4 times. The mean duration of receiving antifungal therapy was 61.4 + 58.02 (range: 1-180) days. The median duration of treatment was 62.5 (range: 42-180) days in survivors. CONCLUSION: Zygomycosis is an infectious disease with high mortality despite antifungal therapy and surgical interventions.

Relationship of antioxidant enzyme activities with myelomeningocele.

AIM: To investigate the role of erythrocyte free radical scavenging enzyme activities (FRSE), carbonic anhydrase (CA) activity and malondialdehyde (MDA) in infants with myelomeningocele (MM). MATERIAL AND METHODS: We compared antioxidant enzyme activities and MDA level in 40 individuals (10 infants with MM, 10 healthy infants; and mothers of these two groups) with age-matched subjects. Erythrocyte FRSE included catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione-S- transferase (GST). RESULTS: CA, CAT, SOD, GPX and GST concentrations were lower in all of the infants with MM compared to healthy infants. The mothers of infants with MM also had lower CA, CAT, SOD, GPX and GST activities than healthy mothers. It was also found out that the MDA level as a marker of oxidative damage was higher in infants with MM and their mothers than in healthy infants and their mothers. CONCLUSION: Lower FRSE activities indicate an increased frequency of MM. Free radicals (FRs) such as MDA may play a significant role in the etiology of MM.

Measurement of evaporation rates of different kind of aqueous solutions under microwave irradiation.

The evaporation rate of water is, of course, different under the same heating conditions of different aqueous solutions. Under conventional heating conditions, the evaporation rate of water is much higher than the evaporation rate of water of aqueous solutions of different kinds of solute materials, which is well accordance with the classical Raoult's law. The results obtained in this study have clearly shown that the chemical characteristics of dissolved materials in water very seriously affect the evaporation rates of water under the microwave heating. This generally causes contradictory results to Raoult's law and this can be explained with the additional microwave energy absorption by the ionic or molecular solute materials found in the solutions other than the microwave energy absorption by water molecules themselves.

Brucellosis: a rare cause of febrile neutropenia in acute myeloblastic leukemia.

Brucellosis is a zoonotic disease and endemically seen in the Middle East, Eastern Europe and continental America. Febrile neutropenia related to Brucellosis has been reported only in a few cases. Brucella was cultured from the bone marrow of a 42-year-old woman who was admitted to hospital with symptoms of fever and fatigue and later diagnosed as acute myeloblastic leukemia (AML). The patient was treated for both AML and Brucellosis without any problems and discharged from the hospital after scheduling her follow-up visits. Brucellosis might be considered in the etiology of febrile neutropenia in endemic regions and must be treated effectively to prevent possible morbidity and mortality during or after chemotherapy.

Serum trace element levels in patients with bladder cancer.

Trace elements are essential components of biological structures, but they can be toxic at concentrations beyond those necessary for their biological functions. In the present study, groups of 35 patients with bladder cancer and 34 healthy volunteer controls were measured for trace elements using a furnace atomic absorption spectrophotometer. Serum levels of Cd, Ni and Co were increased (p<0.05) and Mn and Zn were decreased (p<0.05) in patients with bladder cancer. In the present study, a relationship was seen between the level of trace elements and the occurrence of bladder cancer, suggesting that an increase in the serum level of Cd, Ni, Co and a decrease in the levels of Zn and Mn might be important causes of bladder cancer occurrence; however, defining such a cause-and-effect relationship needs several prospective studies to be done, which seems necessary with regard to the high prevalence of this cancer.

[Investigation of nasal carriage of community-acquired methicillin resistant Staphylococcus aureus in primary and high school students]. / Ilkögretim ve lise ogrencilerinde toplum kökenli metisiline dirençli Staphylococcus aureus burun tasiyiciliginin arastirilmasi.

The aim of this study was to evaluate the carriage rate and risk factors of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) among the students in Manisa, Turkey. A total of 2015 students (1012 from the last phase of high schools and 1003 from the first phase of primary schools) were included in the study. None of the students had nasal MRSA carriage. Methicillin-sensitive S. aureus (MSSA) colonization rate was 14.7% (296/2015). Nasal carriage of MSSA was significantly higher in the primary school students (17.8%) than the high school students (11.6%) (p < 0.001). MSSA carriage was also higher in students of higher socioeconomical status than the students of lower status (p < 0.05). A statistically significant relationship was not determined between the nasal carriage and the risk factors (history of hospitalisation or surgical operation in the previous one year, use of antibiotics or history of skin/soft tissue infection in the last 6 months, presence of children < 15-years-old in the family, presence of healthcare workers in the same house, living in a crowded house). Penicillin and erythromycin resistance was found in 93.6% and 14.2% of MSSA strains, respectively. No resistance was detected against ciprofloxacin, co-trimoxazole, linezolid and vancomycin. There was a statistically significant difference between erythromycin resistance and antibiotic use within the last six months and the number of family members (p < 0.05). In conclusion, current treatment regimens still seem to be affective and safe for the empirical treatment of community-acquired S. aureus infections. Although CA-MRSA infections seem not to be a serious threat in our region yet, it is essential to carry out prevalence studies in the different populations of the community.

Experimental sinusitis in a rhinogenic model.

OBJECTIVES/HYPOTHESIS: The objectives were to determine the optimal sinusitis induction period and to examine microbiological and histopathological changes of sinusitis recovery stage in a rhinogenic sinusitis model. METHODS: A synthetic sponge was inserted into the right-side nasal cavities of rabbits. The sponge was impregnated with a Streptococcus pneumoniae strain in group 1 and with sterile saline solution in groups 2 and 3. After the fourth day of sponge insertion, sinuses were examined by coronal computed tomography scans at two-day intervals until any radiological evidence of sinusitis was observed. When sinusitis was detected radiologically, five rabbits each from groups 1 and 2 were killed for histological examination. To determine the recovery period of sinusitis, sponges were removed from the rest of the rabbits in groups 1 and 2. Rabbits were selected randomly and killed on the 15th and the 30th days of the recovery period, immediately after radiological examinations. Group 3 was considered a sham group. RESULTS: Sinusitis induction was performed in all rabbits in groups 1 and 2 until the 8th day. After the sponges were removed, inflammation persisted until the 30th day of the study. CONCLUSION: In a rhinogenic sinusitis model, although histological features of sinusitis were demonstrated, further studies are required to standardize this model and to examine whether or not the studied bacterial strain spreads from nasal cavity into sinus.

Emergence of phenotypic resistance to ciprofloxacin and levofloxacin in methicillin-resistant and methicillin-sensitive Staphylococcus aureus strains.

The emergence of phenotypic resistance to ciprofloxacin and levofloxacin in methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MRSA) strains was studied. Twenty MRSA and 77 methicillin-sensitive S.aureus (MSSA) strains susceptible to both quinolones were investigated for resistance after single step or serial passages. No growth of 20 MRSA strains was observed at 4xMIC of levofloxacin after 48 h incubation, but 4 of 77 (5%) MSSA strains grew at the same concentration. At 4xMIC concentration of ciprofloxacin, 10 MSSA (13%) and five MRSA (25%) strains were grown. In the serial passages of MRSA strains, resistance to ciprofloxacin was 75 and 5% for levofloxacin by the third passage. In the seventh passage this resistance was 100 and 15%, respectively. In MSSA strains, resistance to ciprofloxacin was 75 and 19% to levofloxacin at the third passage and at the seventh passage, 100 and 61%, respectively. Emergence of ciprofloxacin resistance was more common and developed more rapidly than resistance to levofloxacin in both MRSA and MSSA strains.

Experimental sinusitis in nasally catheterised rabbits.

AIM: The aim of the study was to create an experimental rabbit model for investigating the effects of nasal catheterization on rhinosinus mucosa, bacterial flora and observing the development of bacterial sinusitis. METHODS: Healthy adult white rabbits of either sex and with body weights of 2.5-3 kg were used. Rabbits were randomly separated into two groups; the first group was catheterized by 12 French and the second group was catheterized by 8 French catheters blindly and the non-catheterized left sides were accepted as control. Three randomly chosen rabbits from each group were examined by computerized tomography scans (CT) and sacrified in the first, second and the fourth week of the study. Microbiological and histopathological examinations were performed. RESULTS: In both study groups after the first week of nasal catheterization, opacity or air-fluid level was detected in maxillary sinuses by CT scans, which was significant in group 1. Inflammation spread by the prolongation of nasal catheterization and rapidly development of sinusitis was observed by thicker catheters' usage. CONCLUSION: In this study, the role of nasal catheterization as a predisposing factor in the development of sinusitis and the increase of sinusitis development risk in relation with the catheterization period and the catheters' thickness was shown.