Introduction to XIV updating course of antimicrobials and infectious diseases

Last February, the 14th Course on Antimicrobials and Infectious Diseases Update took place at the Hospital Clínico San Carlos in Madrid. This scientific activity was accredited by the Community of Madrid (Continuing Education Commission for Healthcare Professions of the Community of Madrid, file Exp. 07-AFOC-07063.7/2024) and endorsed by the Spanish Society of Clinical Microbiology and Infectious Diseases (SEIMC), the Spanish Society of Chemotherapy (SEQ), and the Madrid Society of Clinical Microbiology (SMMC). In this edition, the course was held in a hybrid format—both in-person and online—achieving participation from 155 attendees and 786 continuous online connections from Spain and several European and American countries (Figure 1). The audience consisted of multidisciplinary professionals from all infection-related specialities, and the faculty provided an update on the most relevant aspects of bacteriology, mycology, and virology. This issue of the journal includes summaries of the lectures presented.

Diagnostic update

González del Castillo at al. analyzed the usefulness of the Monocyte Distribution Width (MDW) parameter as an early biomarker of infection in critically ill patients seen in emergency departments. This index, integrated into automated blood counts, showed a diagnostic performance comparable to or better than classical biomarkers, with a sensitivity of 73% and a specificity of 72%. Its immediate availability and low cost make it a promising tool for early detection of sepsis (particularly in elderly patients) supporting its integration into clinical algorithms for suspected infection [1-2]. Cercenado and Candel reviewed the main characteristics of the new β-lactamase inhibitors (enmetazobactam, avibactam, relebactam, durlobactam, zidebactam, nacubactam, vaborbactam, taniborbactam, and xeruborbactam), their spectrum of activity, and the available therapeutic combinations. They emphasized how these molecules expand coverage against class A, C, and D enzymes and restore the usefulness of classic β-lactams against Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter baumannii. However, they also warn that emerging resistance during treatment (through KPC mutations, AmpC modifications, or porin loss) requires prudent, microbiologically guided use. Overall, the new BL-BLI combinations (ceftazidime-avibactam, meropenem-vaborbactam, imipenem-relebactam, aztreonam-avibactam, sulbactam-durlobactam, or meropenem-xeruborbactam) represent a crucial advance in managing infections caused by carbapenemase-producing microorganisms, always within an active surveillance framework [3-5]. Cantón and Halperín analyzed the importance of early diagnosis and diagnostic stewardship programs, highlighting the need for 24/7 active laboratories and the incorporation of rapid technologies such as MALDI-TOF or molecular panels. These tools reduce turnaround time, improve therapeutic adequacy, and strengthen collaboration between clinicians and microbiologists in the context of sepsis [6-7]. Sanz, Burillo, and García-Lechuz examined the role of syndromic platforms in the diagnosis of critically ill patients. The simultaneous detection of pathogens and resistance mechanisms through multiplex PCR or microarrays enables early treatment adjustment and reduces hospital stay, consolidating their use as an essential tool in antimicrobial stewardship programs [8-9]. Maldonado-Barrueco and colleagues updated advances in the diagnosis of invasive fungal infections, emphasizing the importance of galactomannan, β-D-glucan, and molecular techniques-together with mass spectrometry to improve early detection of pathogenic fungi and reduce mortality [10-12]. Muñoz-Echeverría and colleagues highlighted the importance of early clinical recognition and immunological and genetic characterization for the diagnosis and management of primary immunodeficiencies in adults, diseases that are often underdiagnosed [13-14].

Therapeutic update

Pina-Sánchez and colleagues reviewed therapeutic optimization strategies against bacteria carrying metalloenzymes, emphasizing the relevance of combinations with new β-lactamase inhibitors and the application of pharmacokinetic and pharmacodynamic principles in clinical decision-making [15-17]. Maseda and Suárez de la Rica focused their analysis on the epidemiological and therapeutic evolution of nosocomial peritonitis, highlighting the increase in multidrug-resistant pathogens and emerging antimicrobial options (ceftazidime–avibactam, meropenem–vaborbactam, imipenem–relebactam, or eravacycline). They addressed the usefulness of rapid molecular techniques for early pathogen identification, the limited role of echinocandins in intra-abdominal candidiasis, and the need to shorten therapy duration through strategies guided by procalcitonin and fungal biomarkers. Their analysis synthesizes a rational, up-to-date approach to complicated intra-abdominal infection in the ICU [18-19]. Soriano-Cuesta and colleagues underlined the importance of empirical treatment adjusted to risk and early de-escalation according to microbiological results. The new antibiotics active against carbapenemases and Acinetobacter spp. represent a key tool for improving clinical outcomes [20-21]. Blanes-Hernández and colleagues challenged the classical dogmas of antibiotic therapy (monotherapy versus combination, treatment duration, or actual impact on resistance), promoting a more rational use based on scientific evidence [22-23]. From the viral infection perspective, Fortún analyzed recent advances in the prophylaxis, monitoring, and treatment of cytomegalovirus, especially in the transplant setting. He highlighted the introduction of next-generation antivirals and the importance of personalized strategies according to risk and resistance [24-25]. Finally, Núñez-Orantos reviewed the latest advances in HIV infection, including long-acting therapies, simplified regimens, and combined prevention strategies (PrEP and vaccination) [26-27].

References

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