COVID-19-Associated Bone Marrow Necrosis-A Case Report

Abstract

We report, herein, a rare case of vertebral bone marrow necrosis in a patient at 1-month post-novel coronavirus disease 2019 (COVID-19) pneumonia complicated with disseminated intravascular coagulation (DIC). The commonly observed radiological features on the imaging modalities like computed tomography (CT), magnetic resonance imaging (MRI), and 18-F fluorodeoxyglucose positron emission tomography (FDG PET) have been discussed here followed by a brief discussion on the role of in-phase and opposed-phase imaging in differentiating the disease from malignant infiltrative pathologies. Histopathological findings on bone marrow smear that confirm the diagnosis have also been illustrated.

Keywords: COVID-19; avascular necrosis; bone marrow necrosis; chemical shift imaging; computed tomography; disseminated intravascular coagulation; magnetic resonance imaging; opposed phase; positron emission tomography; signal intensity index.

Fig. 1

( A ) Axial schematic diagram of blood supply to bony vertebra showing anterior (AC) and posterior central (PC) arteries; black area represents watershed area between AC and PC arteries. ( B ) Midsagittal schematic diagram of two adjacent vertebral bodies with upper vertebra showing vascular territories of AC and PC arteries and lower vertebra showing watershed area (WSA; gray circles) in deep medullary portion and end arterial territory (EAT; white circles) near end plate. Black circles denote areas located within both EAT and WSA and may represent areas more vulnerable to ischemia.

Fig. 2

( A ) STIR mid sagittal image showing hyperintensity in the anterior two-third and hypointensity in the posterior one-third of the vertebral bodies. ( B ) T1 mid sagittal image showing hypointensity in the posterior one-third of the vertebral bodies.

Fig. 3

Axial T1 ( A ) and T2 ( B ) images of L2 lumbar vertebra showing well-defined hypointensity on both T1 and T2 in the posterior one-third of the L2 vertebral body.

Fig. 4

In-phase ( A ) and opposed-phase ( B ) images of cervicodorsal spine showing signal drop on opposed-phase images in the anterior two-thirds of the vertebral bodies signifying viable fatty marrow.

Fig. 5

In-phase ( A ) and opposed-phase ( B ) images of dorsolumbar spine showing signal drop on opposed-phase images in the anterior two-thirds of the vertebral bodies signifying viable fatty marrow.

Fig. 6

18-F FDG PET–CT fusion images ( A and B ) showing heterogeneously increased tracer uptake in the posterior parts of vertebral bodies. CT, computed tomography; FDG PET, fluorodeoxyglucose positron emission tomography.

Fig. 7

Reformatted mid-sagittal ( A, B ) and axial ( C ) CT images showing mild sclerosis with loss of normal trabecular pattern in the posterior parts of the vertebral bodies corresponding to the abnormal T1-hypointense areas seen in Fig. 2 . CT, computed tomography.

Fig. 8

( A, B ) Coronal STIR screening sequence of pelvis with both hips showing well demarcated serpiginous STIR hyperintensity in both femora with the well-described “double line sign” (yellow arrow). STIR, short-tau inversion imaging.

Fig. 9

( A, B ) Bone marrow trephine biopsy sections (A and B; ×40 magnification) with hematoxylin & eosin stain show lymphohistiocytic aggregates (black arrow) and areas of necrosis (white arrow) with neutrophilic debris (yellow arrow) and proliferating fibroblasts in an oedematous background.