Isolated renal and urinary tract aspergillosis: a systematic review.

Background: Aspergillosis localized to the kidneys and the urinary tract is uncommon. We conducted a comprehensive systematic review to evaluate risk factors and clinical outcomes of patients with isolated renal and genito-urinary tract aspergillosis.

Methods: We systematically searched Medline, CINAHL, Embase, African Journal Online, Google Scholar, and the Cochrane Library, covering the period from inception to August 2023 using the key terms 'renal' OR 'kidney*' OR 'prostate' OR 'urinary bladder' OR 'urinary tract*AND 'aspergillosis' OR 'aspergillus' OR 'aspergilloma' OR 'mycetoma'. We included single case reports or case series. Review articles, guidelines, meta-analyses, animal studies, protocols, and cases of genitourinary and /or renal aspergillosis occurring as a part of disseminated disease were excluded.

Results: We identified 91 renal and urinary aspergillosis cases extracted from 76 publications spanning 1925-2023. Among the participants, 79 (86.8%) were male, with a median age of 46 years. Predominantly, presentations consisted of isolated renal infections (74 instances, 81.3%), followed by prostate (5 cases, 5.5%), and bladder (7 cases, 7.7%) involvement. Aspergillus fumigatus (42.9%), Aspergillus flavus (9.9%), and Aspergillus niger/glaucus (1.1% each) were isolated. Underlying risk factors included diabetes mellitus (29.7%), HIV (12.1%), haematological malignancies (11%), and liver cirrhosis (8.8%), while common symptoms encompassed flank pain (36.3%), fever (33%), and lower urinary tract symptoms (20.9%). An autopsy was conducted in 8.8% of cases. Diagnostic work-up involved histopathology (70.5%), renal CT scans and urine microscopy and culture (52.6% each), and abdominal ultrasound (17.9%). Treatments included amphotericin B (34 cases, 37.4%) and azole-based regimens (29 cases, 31.9%). Nephrectomy was performed in 16 of 78 renal cases (20.5%). All-cause mortality was 24.4% (19 cases). No significant mortality rate difference was observed among antifungal regimens (p = 0.739) or nephrectomy status (p = 0.8).

Conclusion: Renal and urinary aspergillosis is an important cause of morbidity and mortality, particularly in immunocompromised and people with diabetes mellitus. While varied treatment strategies were observed, mortality rates showed no significant differences based on treatments or nephrectomy status. Further research is needed to refine diagnostics, optimize treatments, and enhance awareness among clinicians for early detection and management.

Prospero registration number: CRD42023430959.