Frontal osteomyelitis post-COVID-19 associated mucormycosis

Abstract

Rhino-orbito-cerebral mucormycosis (ROCM) is the most commonly noted form of mucormycosis, which is the most common secondary fungal infection following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Osteomyelitis is one of the rare sequelae of ROCM, frontal osteomyelitis being the rarest. We present four patients of coronavirus disease 2019 (COVID-19)-associated mucormycosis, who presented with frontal bone osteomyelitis after being treated for ROCM surgically and medically. This is the first case series highlighting this complication in post-COVID-19 mucormycosis patients and needs utmost attention as it can be life-threatening and can cause extreme facial disfiguration. All four patients are alive with salvage of the affected globe and vision being preserved in one patient. If identified early, disfiguration of face and intracranial extension can be avoided.

Keywords: Frontal bone osteomyelitis; Pott's puffy tumor; fungal orbital and sinus infections; mucormycosis; post–COVID-19 mucormycosis.

Figure 1

(a) Clinical photograph showing the preoperative status. Soft, boggy swelling over the left eyebrow and forehead with mild upper lid edema and ptosis. (b) Postoperative picture showing left-sided craniotomy scar and improved left upper lid ptosis. (c) 3D reconstruction CT showing left-sided, ill-defined lytic and sclerotic lesions suggestive of frontal bone osteomyelitis. (d) Plain CT coronal section showing invasive mucormycosis with involvement of both maxillary antra and ethmoidal and frontal sinuses. Superomedial quadrant of the left orbit with left-sided frontal bone osteomyelitis and subperiosteal abscess. CT = computed tomography

Figure 2

(a) Clinical photograph showing status post-craniotomy and frontal bone excision. (b) 3D reconstruction CT showing postoperative changes with left-sided frontal bone with irregular lytic lesions of both maxillary bones. (c) Contrast CT scan (coronal section) showing postoperative changes post-frontal bone excision and frontal lobectomy, with few hyperdense foci and medial maxillectomy changes with minimal granulation in maxillary antra and ethmoid sinuses. (d) Histopathologic findings of nasal tissue biopsy showing aseptate, broad, ribbon-like fungal hyphae (hematoxylin and eosin stain 40 × magnification). (e) Nasal endoscopy- blackening and crusting of middle turbinate and inferior turbinate. CT = computed tomography

Figure 3

(a) Clinical photograph of patient showing left total ophthalmoplegia, post-craniotomy scar. (b) 3D reconstruction CT showing extensive left-sided irregular lytic and sclerotic lesions, with bone destruction involving bilateral maxillary bone, palatine bone, orbital bones, and postoperative changes in frontal bone on the left side. (c and d) Left-sided frontal craniotomy with aspiration and subtotal excision of abscess. CT = computed tomography

Figure 4

(a) Clinical photography showing right total ophthalmoplegia of the right eye. (b and c) CT orbit and paranasal sinuses coronal and axial sections showing recurrent involvement of ethmoid sinus with proptosis of the right eye, edematous medial rectus, superior rectus, and superior oblique. (d) Nasal endoscopy showing blackening and crustation of middle along with inferior turbinate. (e) Histopathologic examination of sinus tissue biopsy revealing sporangia of mucor with tissue debris (hematoxylin and eosin stain, 40× magnification). CT = computed tomography