Case Report: pharmaceutical care in a case of complicated urinary tract infection combined with disseminated Nocardia brasiliensis infection.

Given the increasing prevalence of multidrug-resistant opportunistic pathogens and the high mortality rate associated with delayed diagnosis of disseminated infections, there is an urgent need for rapid diagnostic tools and closely monitored, individualized anti-infective strategies. This study aimed to explore the critical role of comprehensive pharmaceutical care in managing disseminated Nocardia infections complicated by complicated urinary tract infection (cUTI). Through detailed documentation of a 67-year-old male patient, this study focuses on optimizing antimicrobial regimens based on pathogenetic findings and adjusting treatments for severe adverse reactions. The patient was diagnosed with disseminated Nocardia brasiliensis infection complicated by Enterococcus faecalis urinary tract infection using metagenomic next-generation sequencing (mNGS). The treatment process underwent two critical adjustments. First, during the efficacy optimization phase, the initial empirical meropenem therapy was modified to a reinforced regimen centered on trimethoprim-sulfamethoxazole (TMP-SMX), combined with linezolid and short-term amikacin, effectively controlling the spread of infection. Subsequently, during the safety optimization phase, the patient developed severe thrombocytopenia during sequential oral therapy. Prompt identification and switching to amoxicillin/clavulanate potassium resolved the adverse reactions, enabling successful continuation of subsequent treatment. Follow-up revealed a favorable patient recovery. This case demonstrates that for such complex mixed infections, rapid pathogen diagnosis represented by mNGS serves as the starting point for precision treatment, whereas the intensive combination regimen centered on TMP-SMX forms the foundation for controlling disseminated Nocardia infection. More importantly, the core insight from this case is that successful treatment relies not only on appropriate initial medication, but more critically, on proactive, dynamic pharmaceutical monitoring throughout long-term therapy. This enables early intervention for severe adverse drug reactions and timely, flexible adjustments to treatment regimens, which are essential components for ensuring ultimate therapeutic success in patients with such complex infections.