ATYPICAL AGENTS OF WOUND INFECTION AND TARGETED SAMPLES

Sve otvorene rane su primarno kontaminirane, zatim kolonizirane mikroorganizmima, dominantno bakterijama. Samo neke ~30% kroničnih rana je i inficirano. čimbenici koji pogoduju razvoju infekcije su: velika količina bakterija, prisustvo čimbenika virulencije, te njihova količina i broj, sinergija djelovanja aerobnih i anaerobnih bakterija dominantno, stvaranje formacije biofilma. uobičajeni uzročnici infekcije akutnih i kroničnih rana su: Staphylococcus aureus, MrSA, Streptococcus _-haemolyticus, Pseudomonas aeruginosa, Bacteroides spp, Candida albicans. razlika između akutne i kronične rane je u dominaciji pojedinih uzročnika, s napomenom da Staphylococcus aureus u oba slučaja dominira. Atipični uzročnici infekcija kronične rane su rijetki, neuobičajeni, ne nalazimo ih na području na kojem živimo, ne dokazujemo ih klasičnim standardnim mikrobiološkim metodama, već su nužne molekularne metode. Dominantno su oportunisti, varijabilno iskazuju čimbenike virulencije, ili su izmijenili svoje fenotipske značajke i nisu uzročnici primarnih infekcija rana nego sekundarnih infekcija. Atipični uzročnici infekcija kroničnih rana su raznoliki; iz grupe anaeroba, Peptoniphilus spp, Anaerococcus spp, Bacteroides ureolyticus, Finegoldia magma, zatim grupa gram pozitivnih štapića roda Corynebacterium , grupa bakterija iz akvatične okoline Myocbacterium fortuitum kompleks, Vibrio lginolyticus. Ciljani uzorci su: bioptat - „Zlatni standard“ i/ili aspirat, pri prisustvu značajne količine eksudata. Ciljani uzorci obvezni su pri progresiji i raspadu ležišta rane, povećanju veličine, dubine rane, izolaciji višestruko otpornih mikroba, kada nema kliničkog odgovora na empirijsko antimikrobno liječenje. Pri dijagnostici oportunističkih patogena ili atipičnih uzročnika infekcija kroničnih rana nužna je temeljitost, strpljenje, te revizija bolesnika, dijagnoza, liječenja i uzoraka. Ključno za otkrivanje uzročnika infekcija atipičnih rana je rasprava i dogovor s kliničkim mikrobiologom. Bitno za kvalitetnu dijagnostiku je dekontaminacija rane prije uzimanja ciljanih uzoraka. Ciljani uzorak je bioptat – zlatni standard, rjeđe aspirat što ovisi o količini i sadržaju rane. obrisak kao uzorak se ne preporuča. Ako nema drugog izbora, iznimno se mogu uzeti i površinski obrisci, ali samo uz sljedeće uvjete: dekontaminacija rane uz primjenu lavinove ili Z-tehnike uzimanja obrisaka.All open wounds are primarily contaminated and subsequently colonized by microorganisms, predominantly bacteria. Only about 30% of chronic wounds are also infected. Factors which favor the development of infection are the following: large quantity of bacteria, presence of virulence factors, their quantity and number, predominantly the synergy of aerobic and anaerobic bacteria, and formation of biofilm. Common agents of infection of acute and chronic wounds are Staphylococcus aureus, MRSA, Streptococcus _-haemolyticus, Pseudomonas aeruginosa, Bacteroides spp., and Candida albicans. Difference between acute and chronic wound is in the predominance of individual agents, with an observation that Staphylococcus aureus is predominant in both cases. Atypical agents of chronic wound infection are rare, unusual, not found in the area in which we live, not proven by standard microbiological methods, but molecular methods are needed instead. They are predominantly opportunists, varying in the expression of virulence factors, or they have changed their phenotype characteristics and are not the agents of primary wound infections. They are the agents of secondary infections. Atypical agents of the chronic wound infection are diverse, from the anaerobe group, Peptoniphilus spp., Anaerococcus spp., Bacteroides ureolyticus, Finegoldia magma, the group of gram positive rods of the Corynebacterium genus, the group of bacteria from aquatic environment Mycobacterium fortuitum complex, and Vibrio alginolyticus. The targeted samples are biopsy sample as the “gold standard” and/or aspirate, when a significant quantity of exudate is present. Targeted samples are obligatory when there is a progression and decomposition of the base of the wound, increase in the size or depth of the wound, isolation of multiresistant microbes, or absence of clinical response to empirical antimicrobial therapy. In the diagnosis of opportunistic pathogens or atypical agents of chronic wound infection, it is necessary to be thorough, meticulous, and conduct revision of the patient, diagnosis, treatment and samples. Crucial for the detection of the agents atypical wound infection is discussion and agreement with clinical microbiologist. Essential for the quality diagnosis is decontamination of the wound before taking targeted samples. The targeted sample is biopsy specimen as the “gold standard”, less frequently aspirate, depending on the quantity and content of the wound. Swab as a sample is not recommended. If there is no other choice, only exceptionally surface swabs may be taken, but only under the following conditions: decontamination of the wound with the application of Levine’s or Z-technique of taking of swabs