Epidemiology, antibiotic resistance, treatment and consequences of infections in cancer patients with solid tumors

Infections are the most seen complications in cancer patients. They occur as a result of underlying malignancy and various treatment modality. Cancer patients are tend to develop infection due to an ongoing catabolic situation, malnutrition, ulserative lesions on epidermal and mucosal surfaces, obstructions, invasive procedures, permanent devices, chemotherapy, radiotherapy or malignancys' itself. Despite the great developments in survival, infections are still an important cause of mortality and morbidity in cancer patients. In this study, risk factors, infection sites, distribution of infection factors, antibiogram sensitivities, antibiotic treatment and results of infections in cancer patients with solid tumors are evaluated retrospectively. Among 273 adult patients who were followed up as indoor patients in Akdeniz University Faculty of Medicine Hospital, Department of Internal Medicine, Medical Oncology Clinic between January 2017 and September 2019, patients with pathological diagnosis of solid tumor who hasn't got a hematologic malignancy, with at least one clinically detected infection site, whose infection factor has been isolated with cultur were included in the study and evaluated retrospectively. The most common tumor types are found as lung cancer (71 patients %26,0), upper gastrointestinal tract cancer (39 patients %14,3), and lower gastrointestinal tract cancer (38 patients %13,9), respectively. The risk factors that can create a predisposition to infections in patients with solid tumors were found neutropenia in 31 patients (%11,3), distruption of anatomic barrier in 163 patiens (%59,7), obstruction due to tumor in 85 patients (%31,1), surgery or devices like stents, shunts, prostheses in 42 patients (%15,4), malnutrition in 103 patients (%37,7), loss of the gag reflex in 11 patients (%4,0), and prior antibiotic usage in 151 patients (%55,3). The most common infection sites are found as bloodstream infections in 113 patients (%41,4), respiratory tract infection in 112 patients (%41,0), and genitourinary tract infection in 98 patients (%35,9). In total 369 isolates were extracted from various cultures of 273 patients (114 from blood, 91 from urine, 81 from sputum/trakeal secretion, 30 from pus, 7 from peritoneum, 2 from pleura, 2 from catheter). The most common pathogens are detected as E.coli (102), P.aeruginosa (32), E.fecalis (29). The percentages of types of causative agents are %63,8 for gram-negative bacteria, %27,9 for gram-positive bacteria, %7,5 for fungus, and %0,5 for anaerobic bacteria. In univariate logistic regression analysis, presence of metastasis, inappropriate empirical treatment, having infections which MDR gram-negative bacteria is the causative agent, presence of bloodstream infection, having more than one infection sites and getting total parenteral nutritional support are found significantly associated with mortality. In multivariate logistic regression analysis, the association between mortality and presence of metastasis, getting total parenteral nutritional support are found independently significant. Considering the infection sites, causative infection agents, and local antimicrobial resistance rates, appropiate empirical antibiotic treatment is suggested in infections of cancer patients with solid tumor. Antimicrobial resistance is a global problem who threatens the public health, so appropiate antibiotic usage strategies should be developed in line with epidemiological data in order to minimise the development of resistance. Keywords: Solid tumor, cancer, infection, antimicrobial resistance