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SURVEY ON PENICILLIN SUSCEPTIBILITY OF STREPTOCOCCUS PNEUMONIAE ISOLATED FROM HUNGARIAN CHILDREN AT A PAEDIATRIC HOSPITAL IN BUDAPEST

D. Boriszova, I. Budai, C.L. Marodi, F. Rozgonyi
Pal Heim Children’s Hospital, Hospital of the Ministry of Home Affairs, Budapest, Semmelweis University, Institute of Medical Microbiology, Budapest, Hungary

Objective: To present the penicillin susceptibility of 784 S. pneumoniae isolates from different samples in Hungarian children during the period between April 1, 2000 and August 1, 2002.

Methods and materials: Samples were obtained from children aged between 1 month and 14 years as follows: blood culture 12; pleural fluid 5; CSF 4, tympanocentesis and sinus aspirates 48; conjunctiva 8; nasal and throat swabs 707. Susceptibility tests were performed with 1 mcg oxacillin (Oxoid) screening disc, and penicillin E-test (AB Biodisk, Sweden).

Results: The oxacillin disc screening identified 244 (31%) oxacillin resistant (diameter of the zone of inhibition < 20 mm) isolates. With penicillin E-test, results differed significantly; only 8 isolates (1%) appeared to be penicillin resistant (MIC 2 mg/L); and 194 isolates (25%) were intermediate resistant (MIC 0.12-1 mg/L).

Conclusion: Applying the up to date method (E-test) and NCCLS 2000 guidelines, penicillin resistance of S. pneumoniae isolates appeared to be much lower than it was predicted by the 1 mcg oxacillin disc. Consequently, the value of 1 mcg oxacillin disc screening is questionable.

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STREPTOCOCCUS PNEUMONIAE AND HAEMOPHILUS INFLUENZAE RESISTANCES
IN SANTIAGO DE COMPOSTELA (SPAIN)

E. Leon Muiños, P. Ordoñez Barrosa, E. Prieto Rodriguez, F. Pardo
Perez del Molino Bernal, M.L. Servicio de Microbiologia, Hospital Clinico
Universitario Santiago de Compostela, Spain

It has been studied antibiotics resistances for S. pneumoniae and H. influenzae isolated from 1 January to 30 June 2002; most of them associated with respiratory disease, in the area of Santiago de Compostela (300.000 hab.), Spain. Sensitivity patterns obtained from 96 clinical strains of S. pneumoniae were as follow: penicilin 64.8%; amoxicillin-clavulanate 90.4%; cefotaxime 89.2%; clarithromycin 67.3%; azithromycin 64.6%; telithromycin 100%; ciprofloxacin 64.1 %; ofloxacin 85.3% and levofloxacin 92.8%. Percentages of isolates susceptible to the antibiotics tested of 89 strains of H. influenzae were: amoxicillin-clavulanate 100%; cefuroxime 92.68%; cefotaxime 100%; clarithromycin 69.8 %; azithromycin 97.64%; telithromycin 100%; ciprofloxacin 100%; levofloxacin 100%; cotrimoxazole 74.69% and also 19.3% producing B-lactamases. A multiple-antibiotic resistance pattern was shown by 81.8% of all penicillin high and intermediate-resistance S. pneumoniae. We found 64% multiple-resistances for H. influenzae in those which had betalactamases. Obtained results strongly suggest the necessity for permanent microbiological monitoring of development of the resistance to these organisms, due to frequent use of empirical therapy, almost when new antibiotics are introduced.

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STUDY OF PENICILLIN RESISTANT PNEUMOCOCCI ISOLATED IN ROMANIA BETWEEN 2001-2002

M. Pana, M. Ghita, I. Rebedea, S. Iacob, O. Dorobat, V. Ungureanu,
R. Papagheorghe, N. Popescu, M. Andrei, S. Botea, G. Bancescu, I. Nistor
Cantacuzino Institute, Matei Bals Institute, Victor Babes Hospital, Coltea Hospital,
Emergency Hospital, Carol Davila University, Grigore Alexandrescu Hospital, Romania

Objective: To study the antibiotic resistance in pneumococci isolated last years in Romania.

Methods: 517 strains of Streptococcus pneumoniae coming from sputum or tracheal aspirate (N=263), blood (N=152), CSF (N=79) and others (N=23): ear and eye fluid, sinus, were collected between 2001-2002 at the National Reference Center for Streptococcus. The isolates were tested for susceptibility (MICs) to the following antibiotics: penicillin (Pc), erythromycin (Em), tetracycline (Te), chloramphenicol (Cm), cephalothin (Kf), cefuroxim (Cxm), cefotaxim (Ctx), amoxicillin (Amx), trimethoprim/sulfamethoxazole (Sxt), ofloxacin (Ofx), vancomycin (Va) by standard dilution MIC testing.

Results: Breakpoints were used as proposed by NCCLS 2002. During the study period penicillin-resistant strains (55%) of S. pneumoniae were noted as follows: 65% (MIC50=0.25 mg/l, MIC90=2 mg/l) in sputum and tracheal aspirate, 38.1% (MIC50=0.12 mg/l, MIC90=1 mg/l) in blood, 10% (MIC50=0.06 mg/l, MIC90=2 mg/l) in CSF and 72.4% in others (MIC50=1 mg/l, MIC90=4 mg/l). The penicillin-resistant strains (coming from sputum and tracheal aspirate) showed susceptibility to 3 antibiotics: Amx (100%), Ofx (98.3%), Ctx (86.5%) and resistance to the following antibiotics: Sxt (74%), Em (45%), Kf (43%), Cxm (28.7%), Cm (21%). No resistant strain to vancomycin was found.

Conclusion: The most efficient drugs against penicillin-resistant pneumococci were Amx, Ofx and Ctx. In Romania there is an urgent need for a stronger partnership between clinical medicine and public health for the surveillance of the antimicrobial usage.

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CLINIC AND BACTERIOLOGIC EVALUATION OF COMMUNITY-ACQUIRED PNEUMONIA (CAP) DUE TO STREPTOCOCCUS PNEUMONIAE

S. Iacob, I. Rebedea, M. Pana, A. Cristescu, D. Cocioaba, L. Benea,
C. Marin, M. Ioan
Matei Bals Inst. of Infectious Diseases, Cantacuzino Institute, Bucharest, Romania

Objective: To assess the clinical and bacteriologic characteristics of patients hospitalized with pneumococcal pneumonia in Infectious Diseases Matei Bals Institute (Romania).

Methods: Hospital based retrospective study over a 1 year period (2001-2002).
The patients were diagnosed with CAP according to classical clinical and radiologic criteria. S. pneumoniae was identified at hospitalisation, before antibiotic administration, in sputum samples or hemoculture, from all the patients. Identification and susceptibility testing of S. pneumoniae from clinical samples was performed with API bioMérieux system. The tested antibiotics analyzed were: penicillin, ceftriaxone, levofloxacin, azitromycin, erytromycin, clindamycin, trimethoprim/sulfamethoxazole.

Results: The study included 58 patients between 18-80 years; 60% of the patients were aged 60 or more. Average length of stay was 7 days. Risk factors were associated in 50% of cases (predominently cardiovascular diseases 33% and chronic obstructive pulmonary diseases 17%). Acute onset with fever, chills, and pleuritic pain was observed only in 66% of cases. The pneumonia was complicated in 48% of cases (34% with pleural effusion and 14% with). 24% of patients showed also Ig M seroconversion for Mycoplasma pneumoniae (8 patients 14%), Chlamydia pneumoniae (4 patients 7%), Legionella pneumophila (2 patients 3,5%). The percentages of S. pneumoniae resistance to the tested antibiotics were: penicillin 20%, ceftriaxone 9%, azitromycin and
erytromycin 75%, clindamycin 37%, trimethoprim/sulfamethoxazole 100%, levofloxacin 0%.

Conclusion: Aged patients with cardiovascular diseases and chronic obstructive pulmonary diseases are at high risk for pneumococcal pneumonia. In this group of patients hospitalisation is important to establish the associated pathogens, the antibiotic susceptibility of S. pneumoniae, and also to follow the clinical outcome. In our country levofloxacin seems to be the most appropriate antibiotic in pneumococcal CAP, due to large spectrum and excellent in vitro activity.

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PHARMACODYNAMIC OF NEW SLOWLY-RELEASED PHARMACEUTICAL FORM OF CLARITHROMYCIN FOR PNEUMOCOCCAL PNEUMONIA

N.S. Yutanova, S.V. Sidorenko, S.V. Yakovlev, S.A. Grudinina
State Scientific Center on Antibiotics; Moscow Medical Academy; Moscow, Russia

Study objective: To study pneumococcal susceptibility to Clarithromycin and plasma concentration of the drug after oral administration of new slowly-released pharmaceutical form.

Patients and methods: Clarithromycin blood concentrations after oral administration of slowly-released pharmaceutical form at the dose of 500 mg were studied in 12 patients with community-acquired pneumonia. Susceptibility of freshly isolated S. pneumoniae strains to Clarithromycin was studied using serial dilution method. Strain susceptibility was assessed according to current NCCLS guidelines.

Results: A total of 214 S. pneumoniae strains isolated from patients with community-acquired pneumonia in Moscow in 2002 were tested. 85% of the strains were inhibited by Clarithromycin in concentration of 0.25 mcg/ml or lower. 14% of S. pneumoniae strains were resistant to Clarithromycin. Half (7%) of resistant S. pneumoniae strains demonstrated high-level resistance (MIC 16-32 mcg/ml), the same strains were Clindamycin resistant (MLSB-phenotype). Another half of resistant strains showed low level resistance to Clarithromycin (MIC 1-4 mcg/ml) with retained susceptibility to Clindamycin (M-phenotype). MIC50 and MIC90 Clarithromycin for S. pneumoniae were 0.032 and 4.0 mcg/ml, respectively. Clarithromycin average plasma concentrations in 12 and 24 hours after administration of 500 mg in single oral dose of slowly-released tablets were 1.71 and 0.95 mcg/ml, respectively. Clarithromycin blood concentrations in 12 hours after oral administration (50% of dosing interval) exceeded MIC for 90% of isolated S. pneumoniae strains.

Conclusion: The results of pharmacodynamic studies of Clarithromycin slowly-released pharmaceutical form allow predicting good efficacy of the drug in patients with community-acquired pneumococcal pneumonia.