Ana Kaftandzieva, Zhaklina Cekovska, Igor Kaftandziev, Milena Petrovska and Nikola Panovski
Bacteriology of Wound - Clinical Utility of Gram Stain Microscopy and the Correlation with Culture
Aim: To determine the most common bacteria isolated from wound specimens and to compare those culture results to Gram stain slides.
Material and methods: A total of 1970 specimens from 1788 patients, treated in the University Clinics in Skopje during a one year period were examined by standard microbiology techniques (inoculation onto standard agar media and direct Gram-stained smears). Automatized Vitek system was used for identification of all anaerobes.
Results: Out of a total of 1970 specimens, 1094 (55.5 %) were positive by culture. A total of 1462 strains were isolated: 753 Gram positive (Gram+), 661 Gram negative (Gram-) and 48 anaerobic bacteria. The number of specimens yielding one, two or more different strains was 788, 244 and 62, respectively. Gram + bacteria, in 44.7 % of positive samples were a single isolate. The most commonly isolated potential pathogen was Staphylococcus. In 23.7% samples, Gram negative bacteria were a single isolate (E. coli was the most common isolate). 1094 specimens were positive by culture, 419 (38.3%) were positive by both culture and Gram stain and 675 (61.7%) were negative by Gram stain (leukocytes were present in 276 specimens). 876 specimens were negative by culture, 789 (90%) were negative by both culture and Gram stain (leukocytes were present in 271 specimen) and 87 (9.9%) were positive only by Gram stain.
Conclusion: Our study demonstrated only a 38.3 % of microbiological correlation between Gram stain and culture. This data makes the clinical utility of Gram stain for the microbiological analysis of wounds questionable.
Ana Kaftandzieva, Elena Trajkovska-Dokic, Vesna Kotevska, Zaklina Cekovska and Gordana Jankoska
The aim of the study was to evaluate the association of drug resistance with β-lactamase gene types in ESBL positive E. coli and Klebsiella pneumoniae-Kp.
Material and methods: A total of 251 ESBL-positive E. coli and Kp isolates obtained from urine, tracheal aspirate, wound swab and blood from patients hospitalised at the University Clinics in Skopje were detected using the ESBL set and automated Vitek 2 system. Vitek was also used for susceptibility testing (determination of MIC of 17 antimicrobial agents). Multiplex PCR was used to identify genes for different types of ESBLs in a 100 randomly selected, ESBL positive strains.
Results: More of the 87 ESBL typeable isolates (61%) harbour two or more bla genes and the frequency of antibiotic resistance was high in these isolates, compared to those with a single gene. Isolates with ≥ 3 genes were highly resistant to beta-lactams and non-beta lactams used. The degree of resistance to 3rd generation cephalosporins was also high in these isolates (MIC ≥ 64). More of the ESBL-positive isolates showed higher resistance to cefotaxime than to ceftazidime.
Conclusion: Identification of the genes is necessary for the surveillance of their transmission in hospitals. Surveillance of antibiotic resistance patterns are crucial to overcome the problems associated with ESBLs.
Zhaklina Cekovska, Ana Kaftandzieva, Milena Petrovska, Nikola Panovski, Zoran Spirovski and Hamza Abdulai
Mediastinitis Due to Actinomyces Naeslundii
A 48-year-old man with retrosternal chest pain and upper abdominal pain with propagation to the back, with clinical signs of nausea, dyspnea and dysphagia was referred to the Clinics of thoracic surgery. After esophagography, operative treatment was indicated. Left thoracotomy with mediastinothomy were performed. During the operation, a sample of pus was taken and sent for a microbiological examination at the Institute of Microbiology and Parasitology, Medical Faculty in Skopje. Standard microbiological procedures were used. The sample was cultured anaerobically on Schaedler agar and incubated for 48 hours at 37°C. Oval, smooth colonies were observed. Gram stained smear revealed short branching Gram-positive filaments suspected for genus Actinomyces. For a definitive diagnosis and differentiation of the Actinomyces species, an automated VITEK system was used. Two weeks after treatment by ceftriaxon, metronidazol and analgetics, all clinical signs improved and patient was released in good physical condition.
Ana Kaftandzieva, Margarita Peneva, Branka Petrovska and Zhaklina Cekovska
Pasteurella spp are the first organisms to consider in any patient who presents with a soft tissue infection following cat scratches, or cat or dog bites or licks. Pasteurella canis is most common isolate of dog bites. A case of a 55- year- old woman with symptoms of infected right leg after a dog bite was described. Microbiological examination of the wounds was performed. The collected specimen was used for Gram stain and culture. No bacteria were detected on a direct gram-stained smear from wound specimens. Both aerobic and anaerobic cultures were performed. After 24 hours, growth of smooth, greyish-white colonies was observed only on Columbia agar. Another Gram stained slide was performed from those colonies and Gramnegative cocobacilli to short rodshaped morphology with bipolar staining was observed. They demonstrate positive catalase and oxidase positive reaction. The bacterium was susceptible to all tested antimicrobial agents. Although systemic forms of Pasteurella are possible, cutaneous infections from animal bites is the most common presentation. Most animal-bite injuries can be treated with oral antimicrobials on an outpatient basis. This patient had been managed aggressively at the very early stage, including surgical debridement and peroral antibiotic, which most likely contributed to the absence of further complications