Temenuga Stoeva

Objective: To assess the incidence, timing of onset and etiological spectrum of bacterial infections in patients with hematologic malignancies after allogeneic hematopoietic stem cell transplantation (HSCT), and to compare haploidentical and non-haploidentical recipients. Material and Methods: This retrospective single-center cohort study included 115 consecutive patients with hematologic malignancies who underwent allogeneic HSCT between December 2017 and December 2025 at the Transplant Department of University Hospital “St. Marina”—Varna, Bulgaria. Of these, 38 (33%) received haploidentical and 77 (67%) non-haploidentical grafts. Only microbiologically documented bacterial infections were analyzed. The cumulative incidence (CI) of first bacterial infection of any type and first bloodstream infection (BSI) was estimated using competing-risk methodology, with death before respective infection treated as a competing event. CI curves were compared using Gray’s test and the potential risk factors for first bacterial infection were assessed by Fine–Gray competing-risk regression. Results: Overall, 65 patients (56.5%) developed at least one bacterial infection, with a median time to the first infection of 11 days (IQR: 6–36). The CI of first bacterial infection was 40.0% at day +30 and 52.7% at 1 year; the corresponding cumulative incidences of first BSI were 27.8% and 35.0%, respectively. No statistically significant differences were observed between haploidentical and non-haploidentical recipients in the CI of first bacterial infection or first BSI. A total of 105 bacterial infectious episodes were documented. Their temporal distribution showed different patterns between the two groups, with a greater proportion of early episodes among the non-haploidentical recipients and a greater proportion of later episodes among the haploidentical ones. BSIs were the predominant infectious syndrome, occurring in 46 patients (40.0%; 46/115) and accounting for 63 episodes. Gram-negative bacteria represented 66.2% of BSI isolates, of which 44.2% were multidrug-resistant (MDR). None of the evaluated patient-, disease-, or transplant-related variables was significantly associated with the CI of first bacterial infection. Conclusions: Bacterial infections were common complications after allogeneic HSCT, particularly during the early post-transplant period, with BSIs representing the predominant infectious syndrome. Gram-negative bacteria accounted for most BSI isolates, and a substantial proportion exhibited MDR. No statistically significant differences in the CI of first bacterial infection were observed between haploidentical and non-haploidentical recipients, and donor type was not significantly associated with the risk of first bacterial infection. The distribution of all infectious episodes over the studied time periods showed different patterns between the two groups. These findings should be interpreted in the context of the retrospective single-center design and the relatively small haploidentical subgroup.

Background and Clinical Significance: Cladosporium cladosporioides is a ubiquitous dematiaceous mold that is rarely implicated in invasive human diseases and often considered a saprophyte and plant pathogen. Case Presentation: We report an extremely rare case of C. cladosporioides fungemia in a 61-year-old man with mantle cell lymphoma undergoing chemotherapy. The patient developed fever, dry cough and cavitary pulmonary lesions in the setting of profound immunosuppression. Blood cultures yielded slow-growing dark pigmented mold after prolonged incubation and species identification was achieved using MALDI-TOF mass spectrometry with an alternative fungal database, supported by microscopic morphology. Serum 1,3-β-D-glucan levels were markedly elevated, while galactomannan antigen testing was negative. Antifungal susceptibility testing demonstrated activity of triazoles and targeted therapy with voriconazole led to clinical improvement. A review of the literature identified only five previously reported cases of invasive C. cladosporioides infections worldwide, involving primarily pulmonary and central nervous system disease. Conclusions: To the best of our knowledge, this is the first documented case of fungemia caused by this species. The current report highlights the pathogenic potential of C. cladosporioides in immunocompromised hosts, the diagnostic challenges posed by slow-growing dematiaceous fungi, the importance of prolonged culture incubation, fungal biomarkers and advanced identification techniques for timely diagnosis and management.

Background: Pediatric sepsis is a life-threatening emergency and remains complex to diagnose promptly due to the absence of universally reliable biomarkers. C-reactive protein (CRP) and procalcitonin (PCT) are widely used but have limited effectiveness. We evaluated the diagnostic reliability of presepsin and soluble mannose receptor (sMR) and identified optimal biomarker combinations for distinguishing sepsis from non-infectious systemic inflammatory response syndrome (SIRS) in children. Methods: A total of 80 children were enrolled in this prospective study, including 53 consecutive admissions to the pediatric intensive care unit (PICU) (sepsis, n = 42; non-infectious SIRS, n = 11) and 27 healthy controls. The serum levels of new biomarkers presepsin and soluble mannose receptor (sMR) levels were quantified by ELISA methods and their diagnostic reliability (both individually and combined with CRP and PCT) was assessed using receiver operating characteristic (ROC) curves and multivariate logistic regression. Results: Significantly higher concentrations of all measured markers were found both in septic and other critically ill patients than in healthy controls (p < 0.05). No single biomarker reliably differentiated sepsis from non-infectious SIRS. The sMR + CRP + PCT combination demonstrated the highest diagnostic accuracy (AUC = 0.78, p = 0.0007), surpassing the CRP + PCT model (AUC = 0.71, p = 0.0087). Conclusions: The addition of sMR to the established markers CRP and PCT improves the diagnostic effectiveness in pediatric sepsis. Larger multicenter studies are warranted to confirm clinical utility.