[Fosfomycin susceptibility of urinary Escherichia coli isolates producing extended-spectrum beta-lactamase according to CLSI and EUCAST recommendations]. / CLSI ve EUCAST önerilerine göre genislemis spektrumlu beta-laktamaz üreten Escherichia coli idrar izolatlarinda fosfomisin duyarliligi

The increasing rate of antibiotic resistance in Escherichia coli, the most common pathogen of urinary tract infections (UTIs), leads to difficulties in choosing appropriate antibiotic treatment and achieving treatment success. The aim of this study was to investigate in vitro activity of fosfomycin, presented as a favorable choice for the treatment of UTIs caused especially by extended-spectrum beta-lactamase (ESBL)-producing strains. A total of 244 E.coli strains, of them 118 were ESBL positive and 126 were negative, isolated from urine samples of inpatients and outpatients between May 2011-May 2012, were included in the study. Antibiotic susceptibilities of the isolates were determined by disk diffusion method (DDM) and ESBL production was confirmed by double-disc diffusion method according to the CLSI (Clinical and Laboratory Standards Institute) recommendations. Minimum inhibitor concentration (MIC) values for fosfomycin were detected by E-test method. Fosfomycin zone diameters and MIC values of isolates were interpreted according to the breakpoints of both CLSI and EUCAST (European Committee on Antimicrobial Susceptibility Testing). Susceptibilities of ESBL positive and negative isolates to fosfomycin and other antibiotics, and the results of fosfomycin susceptibility tests obtained by different methods were compared. The correlation between fosfomycin zone diameters and MIC values was calculated. In the study, the resistance rates of ESBL-producing isolates to ciprofloxacin, trimethoprim-sulfamethoxazole, gentamicin and amikacin were detected as 67%, 51%, 51% and 19%, respectively, while those rates were as 9%, 21%, 4% and 11%, respectively in non-ESBL producers. The difference between the two groups were found statistically significant (p< 0.001). Fosfomycin resistance of ESBL-producing and non-producing isolates were 3% and 1%, respectively, indicating no significant difference between the two groups (p= 0.356). According to fosfomycin MIC breakpoints defined by CLSI, 98.3% of ESBL-producing isolates and 100% of non-producing isolates were found susceptible to fosfomycin. According to EUCAST recommendations 98.3% of ESBL-producing isolates and 99.2% of non-producing isolates were found susceptible to fosfomycin. There was no significant difference between ESBL-positive and -negative strains according to CLSI and EUCAST recommendations (p= 0.233 and p= 0.611, respectively). When the methods were compared with each other, there were significant differences between DDM and CLSI-MIC or EUCAST-MIC (p= 0.033 and p= 0.049, respectively) and between CLSI-MIC and EUCAST-MIC (p< 0.001). There was a weak reverse linear correlation between fosfomycin zone diameters and MIC values (r= -0.138, p= 0.032). It was concluded that fosfomycin which had a high activity against ESBL-producing isolates was an appropriate alternative antibiotic in the treatment of UTIs.

[A predisposing clinical condition for disseminated tuberculosis: hairy cell leukemia]. / Disemine tüberküloz için predispozan klinik durum: Tüylü hücreli lösemi.

Hairy cell leukemia (HCL), a rare and slow-progressive B-cell lymphoproliferative disease, enhances predisposition to infectious complications, especially to disseminated mycobacterial infections. Although the association between HCL and mycobacterial disease has been established, disseminated Mycobacterium tuberculosis infection has been reported only in a few case series. In this report, a disseminated tuberculosis (TB) case who had been diagnosed as HCL with histopathologic examination of the bone marrow after being investigated for the etiology of fever of unknown origin, was presented. A 56-year-old male patient who was admitted to our clinic with the complaints of three weeks' duration fever, chills, night sweats and cough was hospitalized. On physical examination, the body temperature of the patient who appeared very ill, was 39°C. Dispersed macular rash that turned pale when pressure was applied, was detected on the legs, arms and back. There were no signs of peripheral lymphadenopathy, hepatomegaly or splenomegaly. Laboratory results revealed haemoglobin 10 g/dl, white blood cell count 1000/mm3, thrombocytes 143.000/mm3, erythrocyte sedimentation rate 41 mm/h, CRP 200 mg/L, uric acid 9.5 mg/dl, AST 118 IU/L, ALT 102 IU/L and LDH 429 IU/L. Thorax computed tomography showed mediastinal and bilateral hilary lymphadenopathy. Although preliminary diagnosis was lymphoma, examination of acid-fast bacilli in three days sequential sputum samples and sputum culture for the growth of mycobacteria (Bactec MGIT 960 TB system, Becton Dickinson, Md) were performed to rule out miliary TB. Blood cultures were also performed with non-radiometric fully automated TB hemoculture bottles (Bactec TB, Becton Dickinson, Md). Sputum cultures yielded no mycobacterial growth, however M.tuberculosis growth was detected in blood culture on the 27th day of inoculation. Bone marrow biopsy revealed HCL. However the patient died on the 14th day of hospitalization. In conclusion, disseminated tuberculosis should be considered for differentional diagnosis in patients with HCL or similar hematologic malignancies since TB is endemic in Turkey.