Invasive aspergillosis complicating diabetes mellitus: a scoping review

Abstract Background Invasive aspergillosis is classically a disease of profoundly immunocompromised hosts, such as those with prolonged neutropenia, haematological malignancy, or transplantation. Diabetes mellitus is increasingly reported as a predisposing condition, at times as the sole or principal risk factor, yet the clinical spectrum, diagnostic patterns, and outcomes of invasive aspergillosis in people with diabetes have not been systematically mapped. We aimed to describe the clinical characteristics, diagnostic approaches, and outcomes of invasive aspergillosis in people living with diabetes mellitus. Methods This scoping review followed the PRISMA extension for scoping reviews. PubMed/MEDLINE was searched for records published between 1980 and 2026, with supplementary searches of the Web of Science Core Collection and Scopus, and reference lists of included articles were hand-searched. In patients with diabetes mellitus as the principal risk factor, we included proven invasive aspergillosis defined by the 2020 EORTC/MSGERC criteria, together with probable disease classified by modified criteria, since diabetes is not a recognised EORTC/MSGERC host factor. Eligible designs were case reports, case series, and observational studies, and we excluded reviews, non-invasive forms, COVID-19-associated aspergillosis, and cases driven by competing immunosuppression. Data were charted and summarised descriptively. Results Of 1322 records screened in PubMed/MEDLINE and 3949 further unique records retrieved by the supplementary searches, 55 cases met the inclusion criteria. The median age was 63 years (range 6 to 84) and 65.3% of patients with reported sex were male. Most cases originated in Asia (60.0%). Rhino-orbital and sinonasal disease was the most frequent clinical form (43.6%), followed by pulmonary (14.5%) and central nervous system disease (12.7%). Where glycaemic status was reported, diabetes was poorly controlled in most patients. Aspergillus fumigatus was the commonest species identified. Overall, 90.9% of cases were proven and the remaining 9.1% were classified as probable by modified criteria. All-cause mortality was 33.3% (17 of 51 cases with a known outcome), and was highest in cardiovascular, disseminated, and pulmonary disease. Conclusions Invasive aspergillosis in people with diabetes mellitus spans a wide anatomical spectrum with a marked predilection for the sinuses and skull base and carries substantial mortality. Diabetes, frequently poorly controlled, may be the only identifiable risk factor. A high index of suspicion is warranted in diabetic patients presenting with invasive sinonasal, cerebral, or pulmonary disease, and tissue-based diagnosis, where it can be obtained safely, is likely to be of value given the limited contribution of non-culture tests in this literature.