Free Papers/International Journal of Antimierobial Agents 26S (2005) $65 Sl12 dosage schedules of antibiotics, suplainhibitoiy concentrations will always be followed by subinhibitory levels. The aim of this research was to determine which of the studied antibiotics exhibits the most desirable effect on the serum resistance of/~ aeruginosa strains. Study Design: Ex vivo study Setting: Two medical wards Hid an intensive care unit in a tertiary government university hospital Population: Clinical isolates of Pseudomonas aerztginosa Methodology: A total of 20 serum resistant/~ aerugmosa strains iso lated from different specimens (urine, bronchial secretions, endotracheal and wound aspirates) were selected. The MICs of ceftazidime, meropenem and gentamicin weie detelmined for each investigated strain. Bacteria were exposed to 1~, 1/4, 1/8, 1/16, and 1/32 of tile MIC of each antibiotic tested. Sensitivity of P. aeruginosa strains to the bactericidal action of normal human serum before and after bacterial exposure to subMICs was determined. Results: Significant difference in serum sensitivity of tile strains was observed after tile bacteria weie exposed to subMICs of ceftazidime and meropenem, wine tile exposuie to subMICs of gentasnicin did not affect the resistance of investigated strains to the bactericidal action of the serum. Upon comparison of the number of serum resistant strains before and after exposure to subMICs of antibiotics, statistically significant differences were determined (p<0.01) Conclusiml: Tile alterations in bacterial mmphology caused by subMICs of ceftazidime and meropenem could be related to subsequent bacterial sensitivity to serum bactericidal activity.
G4.3 Invasion of Bacteria of the Respiratory Tract into Epithelial Cells Apostolos GEORGOPOLrLOS, Clnistina KRATZER, Wolfgmlg GRANINGER. Medical University of Vienna, Austria Objectives: To determine and compare the invasiveness of macrolide sensitive and lesistant GAS and ~-lactamase-producing and non-producing NTHi strains. Significance: Bacterial strains in wlfich tile two features of intracellulas localization and antibiotic resistance occur together fulfill the best qual ifications to persist in the human respiratory tract despite antimicrobial therapy. Group A betwhemolytic streptococcus (GAS) and non typeable Haemophilzts inflztenzae (NTHI), two primary extracellular respiratory tract pathogens, are able to invade and persist inside human epithelial ceils. The intracellulm" compartment protects tile bacteria against tile local host immune system, and provides a partial barrier against the effect of antimicrobial agents. Study Design: In vitro cell culture invasion study Setting: Clinical Department of Infectious Diseases Population: Macrolide-sensitive and iesiatant GAS and ~-lactamaseproducing and non-producing NTHi strains from clinical isolates and nomlal human bronchial epithelial cells (NHBE) and human nasal epithelial cells (HNEpC p). Methodology: All tested bacteria were randomly selected among clinical isolates from patients with community acquired respiratory tract infections in 2003. Tile uptake of bacteria in epithelial cells was evaluated by quantifying tile number of viable intracellulm" bacteria recovered from epithelial cells at tile end of a standm'd antibiotic protection assay after lysis of the epithelial cells. As infection rate, 100 bacterial cells per epithelial cell were used. The incubation times were two hours for streptococci and four hours for haemophili. Results: Tile tested GAS throat isolates exlfibited only weak invasivehess in epithelial cells, and no difference in tile distribution of intracellular macrolide-sensitive and resistant strains was found. For NTHi, an obvious difference of ampicillin sensitive and ~ lactamase positive strains was detected. Only ~ lactamase producing haemophili showed high invasion efficiency. Conclusiml: For S. pyogenes, no association between macrolide-
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resistance and invasiveness was found. On tile other hand, ~-lactasnasepositive NTHI were more invasive than ampicillin sensitive strains
CR. Case Reports CR.1 Aspergillosis: A Case Series Ryan M. LLORIN, Jennifer A. CHUA. St. Luke's Medieal Cente~ Quezon
Ci~, Philippines
Objective: To present a clinical profile of aspergillosis patients encountered in our institution Significance: Aspergillosis has become the most common life threatening invasive mycosis as tile population at risk increases dramatically in tile past decades. Given its wide spectrum of clinical manifestations, a physician should possess a high index of suspicion to recognize this infection. The introduction of newer antifungal agents in re cent years has prompted clinicians to be knowledgeable of its recognition, for early diagnosis portends better outcome. Study Design: Retrospective descriptive study Setting: Tertiary urban mfiversity hospital Population: Hospitalized patients with aspergillosis Methodology: In this retrospective, descriptive study, we reviewed tile charts of patients diagnosed with Aspergillosis who were admitted to the St. Luke's Medical Center from 1998 to 2004. We profiled their clinical characteristics, radiological features, histopathological and culture results, treatment regimens and their outcome. Results: There were 14 cases of Aspergillosis from 1998 to 2004. Tile median age was 54 years. Nine patients (164.3%1) were immunocompromised. The most common immunocompromised states were diabetes mellitus (36%1) and kidney transplantation (121%). Pulmonary aspergillosis was seen in 11 patients while 3 patients had extrapulmonary aspergillosis. In tile pulmonary aspergillosis group, 6 (172%1) had invasive disease. Tile most common manifestations were cough (55%), hemoptysis (155%1) and dyspnea (45%). The most common radiological features were pasenchymal consolidations and infiltrates (64% each) on cheat x-lay and cavitations (180%1) on CT scan. Only one patient was diagnosed by means of both histopathology and culture. Seven patients were diagnosed through culture while three were diagnosed by histopathology. Different antifungal agents were given to patients, with Amphotericin B tile most common treatment regimen and with the most number of adveize reactions. In tile extrapulmonary group, clinical presentation was based on site of involvement. Two were diagnosed through histopathology while one had culture growth. Radiological exams showed tissue masses. Surgical resections were per formed successfully while one underwent oral antifungal therapy. The case fatality rate of pulmonary aspergillosis was 27% wine all survived in tile extrapulmonaxy aspergillosis group. Conclusiml: Aspergillosis has become a foianidable infection in a time of increasing immunosuppression. Early diagnosis is important in achieving favorable results. With newer antifungal agents, prognosis may eventually improve. In the meantime, novel treatment strategies are being exploied.
CR.2 Tuberculosis of the Cervix Uteri Mimicking Cervical Malignancy: A Case Report Ma. Angela S. RODRIGUF~ BANDOLA, Ricardo M. MANALASTAS JR.. Phihpp#ze General Hospital - Universi~ of the Philippines, Manila,
Philippines Objectives: To discuss a case of cervical tuberculosis presenting as cervical cancer mid to review tile literature regarding cervical tubelculosis.