The use of imaging to identify immunocompromised children requiring biopsy for invasive fungal rhinosinusitis

Background and purpose Children with severe immunocompromise due to cancer therapy or hematopoietic cell transplant are at risk both for potentially lethal invasive fungal rhinosinusitis (IFRS), and for complications associated with gold-standard biopsy diagnosis. We investigated whether early imaging could reliably identify or exclude IFRS in this population, thereby reducing unnecessary biopsy. Methods We reviewed clinical/laboratory data and cross-sectional imaging from 31 pediatric patients evaluated for suspicion of IFRS, 19 without (age 11.8 +/- 5.4 years) and 12 with proven IFRS (age 11.9 +/- 4.6 years). Imaging examinations were graded for mucosal thickening (Lund score), for fungal-specific signs (FSS) of bone destruction, extra-sinus inflammation, and nasal mucosal ulceration. Loss of contrast enhancement (LoCE) was assessed separately where possible. Clinical and imaging findings were compared with parametric or nonparametric tests as appropriate. Diagnostic accuracy was assessed by receiver operating characteristic (ROC) analysis. Positive (+LR) and negative likelihood ratios (-LR) and probabilities were calculated. Results Ten of 12 patients with IFRS and one of 19 without IFRS had at least one FSS on early imaging (83% sensitive, 95% specific, +LR = 15.83, -LR = 0.18;P < .001). Absolute neutrophil count (ANC) <= 200/mm(3)was 100% sensitive and 58% specific for IFRS (+LR = 2.38, -LR = 0;P = .001). Facial pain was the only discriminating symptom of IFRS (P < .001). In a symptomatic child with ANC <= 200/m(3), the presence of at least one FSS indicated high (79%) probability of IFRS; absence of FSS suggested low (<4%) probability. Conclusion In symptomatic, severely immunocompromised children, the presence or absence of fungal-specific imaging findings may effectively rule in or rule out early IFRS, potentially sparing some patients the risks associated with biopsy.