Hyperbaric oxygen therapy in necrotizing soft tissue infections caused by Vibrio species from the Baltic Sea - three clinical cases.

We read with great interest the report on the presence of Vibrio spp in the Gulf of Gdansk, Baltic Sea, Poland by Kurpas et al. [1]. So far, the vast majority of identifications of Vibrio spp in open waters concerned the subtropical zone. In an analysis of 19 publications describing 2,227 patients with NSTI caused by Vibrio vulnificus, 95% of cases concerned such subtropical zones [2]. However, there are also reports describing the changing location of Vibrio, mainly due to the gradual increase in open water temperature [3]. The identification of Vibrio spp in the climatic zone of the Baltic Sea is a new observation that is of great importance not only from the microbiological point of view but also for clinical reasons. Vibrio is one of the more common bacteria in tropical or subtropical waters. It is a gram-negative rod that can cause necrotizing soft tissue infection (NSTI), which also includes necrotizing fasciitis, and often leads to septic shock and an immediate threat to life. From the aetiology point of view, NSTI most often has a polymicrobial aetiology, often described as type I, or monomicrobial, usually described as type II (most often caused by group A beta-haemolytic streptococci, e.g. Streptococcus pyogenes), sometimes in combination with Staphylococcus aureus [4, 5]. According to the same classification, infections caused by Vibrio spp are referred to as type III related to other less common causative agents (e.g., Clostridium spp, Aeromonas spp, Vibrio spp). Type IV describes fungal infections (e.g., Candida spp, Zygomycetes). Regardless of aetiology, the treatment of any form of NSTI is multimodal and includes surgery, antibiotic therapy, and haemodynamic sepsis management [4–8]. In the case of Vibrio NSTI, the importance of surgical interventions is emphasized [9]. Most of the recommendations also suggest using hyperbaric oxygen therapy (HBOT). In the literature, one can find descriptions of clinical cases successfully treated with HBOT, but in most of those reports the infections came from sub-tropical waters of the United States or Japan [10, 11]. An interesting coincidence is a fact that at almost the same time as the publication by Kurpas et al. [1] on the occurrence of Vibrio spp in the Gulf of Gdansk, a clinical case report of a 68-year-old patient with NSTI caused by Vibrio vulnificus, most probably from the south-western part of the Baltic Sea, treated with adjunctive HBOT in our department was published [12]. In summary, after injuring while swimming in Baltic seawater, the patient developed NSTI of the lower extremity. Vibrio vulnificus was identified in blood. Initially, this patient was treated in a local municipal hospital. However, due to the progression of NSTI confirmed in computed tomography scan, with increasing inflammatory markers and general deterioration with sepsis, the patient was transferred to our department, where he underwent surgical debridement with general care using antibiotics (ceftriaxone, ciprofloxacin, doxycycline), septic shock management and adjunctive HBOT. After 5 days of treatment in our department, where 10 HBOT sessions were performed, the general and local condition improved. Control cultures were negative and inflammation markers decreased: white blood cell (WBC) count from 13.93 G/L to 8.58 G/L; C-reactive protein (CRP) from 137.9 mg/L to 36.9 mg/dL, procalcitonin (PCT) from 8.52 ng/mL to 1.3 ng/mL. After this treatment, the patient was transported back to the referring unit for further treatment.