[Treatment of hemodialysis catheter-associated bacteremia due to methicillin-resistant Staphylococcus aureus by daptomycin lock method]

Treatment of catheter-associated infections caused by Staphylococcus aureus is difficult without catheter removal, because of the biofilm formation and its high virulence. In this report, we presented our clinical and microbiological experience with systemic daptomycin (6 mg/kg/on alternate days IV) as well as antibiotic lock therapy (filling of the catheter lumen with 3.5 mg/ml daptomycin together with 0.045 mg/ml calcium) in the treatment of a catheter-associated bloodstream infection caused by methicillin-resistant S.aureus in a patient with hemodialysis catheter which could not be removed.

[Investigation of the frequency of PER-1 type beta-lactamase and antimicrobial resistance rates in nosocomial isolates of Pseudomonas aeruginosa]

Pseudomonas aeruginosa which is a common cause of nosocomial infections, usually leads to treatment difficulties due to multi-drug resistance. PER-1 type extended-spectrum beta-lactamase (ESBL) producing bacteria are shown to be common in Turkey. Since limited number of antibiotics such as antipseudomonal penicillins, cephalosporins, aminoglycosides, fluoroquinolones and carbapenems are available for the treatment of P.aeruginosa infections, it is essential to monitor and eventually control the spread of antibiotic resistance genes. The aims of this study were to investigate the presence of PER-1 type ESBLs in nosocomial P.aeruginosa isolates and to evaluate their resistance to some commonly used antibiotics. A total of 110 P.aeruginosa strains isolated from clinical samples [40 urine, 26 exudate, 20 blood, 24 others (sputum, tracheal aspirate, tissue biopsy, cerebrospinal fluid, pleural fluid, conjunctiva)] of the inpatients who were proven to have nosocomial infections in Ondokuz Mayıs University Faculty of Medicine Hospital between May 2002-June 2003 were included in the study. Identification of the isolates was performed by ATB system ID 32 GN (bio-Merieux, France). Antibiotic susceptibilities were detected by standard disk diffusion method and PER-1 type ESBL was searched by polymerase chain reaction using PER-1 and PER- 2 primers. PER-1 positivity was detected in 62 of 110 (56.4%) P.aeruginosa isolates and 51 of 65 (78.5%) ceftazidime-resistant strains. The highest susceptibility rate was detected for ciprofloxacin (76.4%), while the lowest susceptibility rate was for ticarcillin-clavulanic acid (22.7%). Rates of resistance to beta-lactam agents (excluding piperacillin/tazobactam), amikacin and gentamicin were statistically significantly higher for PER-1 positive strains than PER-1 negative ones. Resistance rates to ceftazidime, cefepime, aztreonam, piperacillin and ticarcillin-clavulanic acid in PER-1 positive isolates versus negative ones were as 82.3% vs. 29.2% (p< 0.01), 75.8% vs. 25% (p< 0.01), 83.9% vs. 30.4% (p< 0.01), 73.8% vs. 52.2% (p< 0.05), 85.5% vs. 66.7% (p< 0.05), respectively. Considering resistance rates to piperacillin-tazobactam and ciprofloxacin, PER-1 positive isolates versus negatives were 35.5% vs. 31.3%, and 19.4% vs. 29.2%, respectively, revealing no statistical significance (p> 0.05). As a result, PER-1 type ESBL frequency and beta- lactam and aminoglycoside resistance rates were found remarkably high in nosocomial P.aeruginosa strains isolated in our hospital. It was concluded that antibiotic resistance should be continously monitorized and necessary measures to prevent further increase in resistance should be promptly established.

Comparison of the adherence of E.Coli and S. Aureus to ten different prosthetic mesh grafts: In vitro experimental study

BACKGROUND

The prosthetic mesh grafts used to repair the abdominal wall may become infected, primarily by S. aureus and E. coli. This study sought to provide a rational basis for the choice of mesh used to repair a hernia when there is a likelihood of infection or contamination.

METHODS

S. aureus and E. coli were incubated with ten types of prosthetic mesh graft (Table 1) in liquid growth medium. After sequential dilution of samples from the prosthetic mesh grafts, the colony forming units of adherent S. aureus and E. coli were counted.

RESULTS

There was no significant difference in the numbers of E. coli and S. aureus adherent to simple polypropylene mesh grafts. Significantly more of both species were adherent to the polyester, expanded polytetrafluoroethylene (ePTFE), and composite prosthetic mesh grafts, except for E. coli on graft 5. Significantly fewer E. coli were adherent to composite mesh grafts 5, 8, and 10 than S. aureus.

CONCLUSION

S. aureus and E. coli adhere to polypropylene similarly. In vitro, fewer S. aureus and E. coli adhere to simple polypropylene mesh grafts than to polyester, ePTFE, or composite prosthetic mesh grafts.

[A rare case of endocarditis due to Moraxella catarrhalis in an immunocompetent patient]

Moraxella catarrhalis is a gram-negative, catalase and oxidase positive diplococcus. While it causes otitis media, sinusitis, bronchitis and conjunctivitis in children and adults, it has a tendency to cause lower respiratory tract infections in older ages. More severe clinical pictures with the range of sepsis to endocarditis are also seen in immunocompromised patients. In this report, a case of M. catarrhalis endocarditis in an immunocompetent host who needed valve replacement has been presented. Forty three years old female patient was admitted to our hospital with the complaints of fever, nausea, night sweating and arthralgia for 20 days. Physical examination revealed systolic murmurs on the apex, and vegetation on the atrial surface of mitral valve was detected by transthoracic echocardiography. Intravenous (IV) ampicillin (4 x 3 g/day) and gentamicin (3 x 80 mg/day) treatment was started empirically with prediagnosis of infective endocarditis. The treatment was modified to IV ceftriaxone (1 x 2 g/day) and gentamicin (3 x 80 mg/day) due to the reporting of gram-negative bacilli in blood culture (BacT/ALERT 3D, bioMérieux, France) on the next day. Gram-negative cocobacilli/diplococci were detected with Gram stain on the smear prepared from the blood culture bottle. Simultaneous subcultures to blood agar and eosin methylene blue agar yielded white colored, S-type, non-hemolytic colonies on only blood agar. Catalase and oxidase tests were positive, while beta-lactamase activity was negative. The isolate was identified as M. catarrhalis by using API NH (bioMérieux, France) identification strips. M. catarrhalis was isolated from five different blood culture specimens of the patient. The focus for bacteremia could not be detected. The patient underwent mitral valve replacement operation as an emergency since the vegetation exhibited rapid growth on the fifth day of medical treatment. Antibacterial therapy was completed for 6 weeks. Control echocardiography revealed that artificial mitral valve was open and functional, thus the patient recovered completely without sequela. In conclusion, M. catarrhalis should be considered as a possible cause of infective endocarditis even in immunocompetent patients.

[Case report: a nosocomial infection caused by vancomycin resistant enterococcus]

Vancomycin resistant enterococcus (VRE) was recovered from the urine culture of a 61 years old female patient, who was being treated for sepsis, on the 15th day of hospitalization in Ondokuz Mayis University Hospital Infectious Disease Unit. The underlying diseases of this patient were chronic renal failure and diabetes mellitus. The patient died due to septic shock on the day of VRE isolation. Since this case was the first VRE infection in our hospital, a point prevalence study was planned. For this purpose, rectal swab samples collected from 10 patients from the same unit and 27 personnel who worked in the same unit, were screened for the presence of VRE. Nasal swabs and finger tip samples were also taken from the staff to determine if the transmission has occured in this way. As a result, a second VRE strain was isolated from another patient with chronic renal failure who was under treatment due to multiple pulmonary abscesses. Immediate isolation of this patient prevented a possible epidemic in this specific unit. In this report, the importance of VRE screening and isolation of the patients after the recovery of VRE has been emphasized.

[Seroprevalence of hepatitis B and C infections in surgical personnel and evaluation of predisposing factors]

The aim of this study was to investigate the seroprevalence of hepatitis B and C infections in the personnel of the operating room of Ondokuz Mayis University Hospital, to detect the carriers and actively infected individuals, to find out the health-workers' behaviours for the prevention from these infections, and to ascertain the risk factors of these diseases. HBsAg, anti-HBc, anti-HBs and anti-HCV antibodies were examined in the serum samples of 190 personnel, and their gender, education, working time (year), the daily working time in operating theatre (part/full time), the history of past hepatitis B infection, hepatitis B immunization, history of a past operation and blood transfusion, and the use of gloves during working (continuously-intermittent) were questioned. As a result, no carrier and/or actively infected personnel with hepatitis B and C were detected, while 36 (18.9%) of them had a history of past hepatitis B infection, and 132 (69.5%) of them had hepatitis B vaccine. The continuous glove use was more common in part-time workers than those of full-time workers, the history of past hepatitis B infection was increasing as the duration of working years increase, and the rates of being vaccinated against hepatitis B was decreasing as the duration of working years increase (p < 0.05).

Acute renal failure in leptospirosis in the black-sea region in Turkey

Leptospirosis is an infectious disease caused by pathogenic leptospires and is characterized by a broad spectrum of clinical manifestations, varying from inappearent infection to fulminant, fetal disease. Eighty-five to 90% of leptospirosis infections are self-limiting. However, 5-10% of infection by L. interrogans can cause renal tubular damage, microvascular injury, acute renal failure (ARF), and interstitial nephritis. We studied 36 patients with leptospirosis. Twenty-seven (65%) cases of 36 patients had ARF. Fourteen (51%) had nonoliguric ARF. In thirteen (48%) oliguria appeared on the third or fourth days of hospitalization. Serum BUN, creatinine, serum bilirubine, ALT, AST, potassium and thrombocytopenia levels were higher in oliguric than nonoliguric patients (p < 0.05). However, serum sodium, CPK levels were not different between oliguric and nonoliguric groups (p > 0.05). Thirteen patients (48%) needed in renal replacement therapy (RRT). 8 of them were treated by hemodialysis (HD) alone and 5 patients by HD in combination with hemoperfusion. Twenty-five patients (92%) recovered completely after 3-5 weeks. Two patients (7.4%) who had severe hepatorenal and hemorrhagic syndromes, died. We concluded that till now leptospirosis is actual problem for nephrologist in the developing countries because of very high percentage of renal disease, with good prognosis in patients without multiorgan failure and early treatment.

Thrombocytopenia complicating the clinical course of leptospiral infection

Leptospirosis can present with a wide clinical spectrum, and haematological manifestations are often apparent. We retrospectively analysed platelet counts in 49 patients with leptospirosis. Forty-three patients (87.8%) had thrombocytopenia. Mean baseline platelet counts rose from 69 x 10(9)/l to 151 x 10(9)/l following treatment. Haemorrhagic episodes were observed in 11 patients. Platelet nadir was 29 x 10(9)/l in the group experiencing bleeding and 64 x 10(9)/l in the remainder. Six patients died due to bleeding and one due to sepsis. Thirty-six patients (73.5%) had acute renal failure; their means platelet count was 46 x 10(9)/l. Liver enzyme levels were elevated in all patients. Thrombocyte count, liver enzyme levels and bilirubin levels were significantly correlated. Forty-three (87.8%) patients showed signs of sepsis; mean thrombocyte count was 46 x 10(9)/l in these patients, and 133 x 10(9)/l in those without sepsis. Multiple organ involvement and fulminant disease is usually associated with renal failure and/or thrombocytopenia in leptospirosis.

Surveillance of antimicrobial resistance among gram-negative isolates from intensive care units in eight hospitals in Turkey

With the participation of eight major reference hospitals in Turkey, 749 aerobic Gram-negative isolates obtained from 473 intensive care patients in 1997 were tested for their susceptibility to 13 commonly employed antibacterial agents. The frequency with which species were isolated and resistance rates were compared with data from the previous 2 years. Imipenem was the most active agent against the majority of isolates (75%), followed by ciprofloxacin, cefepime and amikacin. The per cent susceptibility to all antibiotics declined from 1995 to 1996. With the exception of imipenem, for which there was no change in resistance, the per cent susceptibility somewhat increased in 1997. However, it was still lower than in 1995.

A surveillance study of antimicrobial resistance of gram-negative bacteria isolated from intensive care units in eight hospitals in Turkey

This study was carried out with the participation of eight hospitals in Turkey to determine the frequency of gram-negative bacteria isolated in intensive care units (ICU) and to compare their resistance rates to selected antibiotics. Aerobic gram-negative bacteria isolated from ICUs during 1996 were studied. Antibiotic susceptibilities to imipenem, ceftazidime, ceftazidime-clavulanate, ceftriaxone, cefotaxime, cefepime, cefodizime, cefuroxime, piperacillin/tazobactam, amoxycillin-clavulanate, gentamicin, amikacin and ciprofloxacin were determined by Etest. A total of 748 isolates were obtained from 547 patients. The majority of organisms were isolated from the respiratory (38.8%) and urinary tracts (30.9%). Pseudomonas spp. were the most frequently isolated gram-negative species (26.8%), followed by Klebsiella spp. (26.2%). Escherichia coli, Acinetobacter spp. and Enterobacter spp. were the other commonly isolated organisms. High resistance rates were observed for all antibiotics studied. Imipenem appeared to be the most active agent against the majority of isolates. Although resistance rates exceeded 50%, ciprofloxacin, cefepime and amikacin were found to be relatively effective. Extended-spectrum beta-lactamase (ESBL) production appeared to be a major mechanism of resistance to beta-lactam antibiotics. In contrast to ceftazidime-clavulanate, piperacillin/tazobactam showed poor activity against organisms thought to produce ESBL, suggesting the presence of an enzyme resistant to tazobactam action. This study has yielded high rates of resistance in aerobic gram-negative isolates from ICUs in Turkey. High resistance rates to all the other antibacterials studied leave imipenem as the only reliable agent for the empirical treatment of ICU infections in Turkey.

[Hepatitis markers in hemodialysis patients]

In this study, antibodies against blood-borne hepatitis viruses (Hepatitis B, C and D) were investigated by ELISA in 43 patients with chronic renal insufficiency, at Hemodialysis Unit of Ondokuz Mayis University, Faculty of Medicine. 32 (76.2%) of the patients were found positive Anti-HBc total antibody and 12 (27.5%) patients were HBsAg carriers. 14 (32.5%) patients had Anti-HBs which showed protective immunity. Anti-HBs antibody was found negative in 6 patients after Hepatitis B infection. 9 (75%) of the HBsAg carriers had Anti-Delta antibody. 34 (79.1%) patients showed Anti-HCV positivity, 6 (18.2%) of HCV seropositive patients were found to be positive for HBsAg. There wasn't any correlation between length of time on hemodialysis, age and seropositivity of hepatitis markers. A correlation was detected between multiple transfusion and Anti-HCV seropositivity. The prevalence of HBsAg, Anti-HBc total and Anti-HCV were sequentially found 6%, 38%, 1% among healthy blood donors taken as a control group. Hepatitis virus infection was frequently seen in hemodialysis patients because of multiple blood transfusion. Chronicity is high because of insufficiency of cellular and humoral immunity. Testing blood for hepatitis viruses markers before blood transfusion and Hepatitis B vaccination programme might control viral hepatitis infection in hemodialysis units.

[Hepatitis b seroprevalence in hospital personnel]

To investigate the epidemiology of viral hepatitis B (VHB) infection in Ondokuz Mayis University Hospital staff sera of 243 workers and 100 blood donors examined for HBsAg and Anti-HBs with ELISA. The prevalences of HBsAg and Anti-HBs among the workers were 8.6% and 33.7% and among the blood donors were 5 and 24%, respectively. The overall prevalence of donors was 29%. The risk of infection showed a correlation with age and working period but there was no difference according to the jobs and departments. According to these results hospital staff have a great risk for VHB and should be vaccinated for protection from the infection.

[Importance of the enzyme-linked immunosorbent assay (ELISA) for the serologic diagnosis of tuberculosis]

Tuberculosis is still a major granulomatosis disease in developing countries. The diagnosis of tuberculosis infection frequently creates problems which is related to clinical, radiological and bacteriological investigations. Recently, immunoenzymatic assays provide hopeful results for the serodiagnosis of tuberculosis. In this study, ELISA was evaluated as a serodiagnostic test for tuberculosis. Sera were obtained from 40 pulmonary tuberculosis patients and 15 healthy volunteer donors. The results showed that ELISA could be used in the serologic diagnosis of pulmonary tuberculosis.