Advances in the Diagnosis of Invasive Pulmonary Mold Infections: Focus on Diagnostic Performance and Cost-Effectiveness of Diagnostic Tests

Background/Objectives: Invasive pulmonary mold infections (IPMI) are critical complications in immunocompro-mised patients, contributing significantly to morbidity and mortality. Diagnosing pathogens like Aspergillus and Mucorales remains challenging due to non-specific clinical presentations and the limitations of traditional culture methods. This review provides an up-to-date synopsis of IPMI diagnostic tools, focusing on their diagnostic perfor-mance, turnaround time (TAT), and cost-effectiveness. Methods: We conducted a narrative review of current literature regarding clinical evaluation, radiographic findings (Computerized Tomography), invasive diagnostics (Bronchoalveolar Lavage and biopsy), and non-invasive assays, including next-generation sequencing (NGS) and volatile organic compounds (VOCs). Results: Chest CT remains a vital first step, though classic signs like the "halo" or "reversed halo" are neither sensitive nor specific. Traditional diagnostics are limited by low sensitivity and delayed results. While plasma microbial cell-free DNA (mcfDNA) NGS offers rapid TAT (24–48 hours) and high specificity, its suboptimal sensitivity for Aspergillus (< 50%) and high cost remain significant barriers. Investigational VOC "breath tests" show promising sensitivity (77%–96%) but lack standardization. Conclusions: Future research must prioritize the standardization of non-invasive microbiologic testing modalities, particularly those with rapid TAT such as bedside "breath tests" and high-throughput NGS. Furthermore, the de-velopment of clinical algorithms that balance cost-effectiveness with timely pathogen diagnosis based on the patient’s degree of immunosuppression is essential to improve survival in high-risk populations.