Invasive fungal rhinosinusitis versus bacterial rhinosinusitis with orbital complications: a case-control study

Radiological differentiation between bacterial orbital cellulitis and invasive fungal sino-orbital infections

PURPOSE

Invasive fungal orbital infections (IFOI) may be difficult to differentiate from sinogenic bacterial orbital cellulitis (OC). This study investigates the features differentiating OC from IFOI on magnetic resonance imaging (MRI).

METHODS

Retrospective study of adult patients with sinogenic OC and IFOI with pre-intervention MRI. Patients without post-septal involvement, non-sinogenic OC (e.g.: secondary to trauma) and poor-quality scans were excluded. Independent Sample's t test and Fisher's exact test were conducted with p < 0.05 deemed statistically significant.

RESULTS

Eleven cases each of OC (Mean age: 41.6 ± 18.4 years-old, Male: 10) and IFOI (Mean age: 65.0 ± 16.6 years-old, Male: 9) between 2006 and 2023. IFOI patients were older, more likely immunocompromised and had a lower mean white-cell count (p value = 0.005, 0.035 and 0.017, respectively). The ethmoid and maxillary sinuses were most commonly involved in both entities. Pre-septal and lacrimal gland involvement were more common in OC (p = 0.001 and 0.008, respectively). Infiltrative OC orbital lesions were poorly demarcated, whilst those in IFOI were expansile/mass-like invading the orbit from the adjacent paranasal sinuses. Specific IFOI features included loss-of-contrast-enhancement (LoCE) of paranasal sinus tissues with orbital extension. Extra-orbital and -sinonasal extension indicative of IFOI included contiguous skull base or pterygopalatine fossa involvement, retro-antral and masticator space stranding and vasculitis.

CONCLUSION

This study describes the key MRI features of IFOI including differentiating markers from OC. These specific features, such as LoCE of the paranasal and orbital soft tissues, the location and pattern of contiguous soft-tissue involvement, provide expedient identification of IFOI which necessitate early surgical intervention for microbiological confirmation of an invasive fungal pathology.

Managing acute invasive fungal sinusitis

Acute invasive fungal sinusitis is the most aggressive form of fungal sinusitis and can be fatal, especially in patients who are immunosuppressed. Early diagnosis and intervention are crucial and potentially lifesaving, so primary care providers must maintain a high index of suspicion for this disease. Patients may need to be admitted to the hospital for IV antifungal therapy and surgical debridement.

Impact of treatment time on the survival of patients suffering from invasive fungal rhinosinusitis

BACKGROUND

Invasive fungal rhinosinusitis is an uncommon disease with high mortality rates. There is currently no consensus on the best treatment timing. We studied the impact of the treatment timing on the survival of patients experiencing invasive fungal rhinosinusitis.

METHODS

We conducted a retrospective study of patients suffering from invasive fungal rhinosinusitis. The duration of symptoms, clinical presentations, clinical signs, diagnoses, treatments, and outcomes were collected.

RESULTS

It was observed that more than 70% of the mortalities occurred within the subgroup of patients who exhibited symptoms of the disease within 14 days before admission.

After adjusting for the confounders, the time taken to treat the patients was the most statistically significant predictor for mortality (P = 0.045). We found no significant relationships between mortality and its significant covariates, which included the underlying diseases (P = 0.91) or complications (P = 0.55).

CONCLUSIONS

Our study demonstrates that the time taken to treat the patients is an important determinant for the survival of patients who are afflicted with invasive fungal rhinosinusitis. The appropriate treatments should be administered within 14 days from the time the symptoms begin to manifest.