Skeletal manifestations of eosinophilic granuloma (eg)

Skeletal manifestations of eosinophilic granuloma (EG)

Presented by Dr.laith Fadhel

reference David Sutton 1340

• Epidemiology /The skeletal system is the commonest site of involvement of Langerhans cell histiocytosis, and in for 60-80% of cases is the only organ system involved.

• Aged affected / children 3-12 years / young adult / male predominance • location / skull , pelvis , femora , diaphysial predilection • Symptoms / pain , swelling , fever • Presentation / solitary , multiple lesions • Radiological sign / lucent area of bone distraction , Sharpe oval or scalloped margin , bone expansion , in chronic phase with sclerotic margin , collapse vertebra • DDX / osteomyelitis , Ewing's tumor , in spine / metastases , atypical TB , neuroblastoma

Skull

1. Isolated lesion 2. Bone expansion 3. Sharpe margin Oval ,

scalloped 4. DDX / epidemoid or

fibrous dysplasia

Spine

1. collapse vertebra { vertebra plana }

2. wall bulging laterally 3. disc intact 4. Para spinal soft shadow

Spine

1. collapse vertebra { vertebra plana }

2. wall bulging laterally 3. disc intact 4. Para spinal soft shadow5. CT / cortical erosion and

soft tissue involvement

Spine MRI / T1 - typically low signal T2 - isointense to hyper intense STIR - hyper intenseT1 C+ (Gd) - often shows contrast enhancement

PT Bone scanVariable appearance on bone scintigraphy with lesions showing an increased or decreased tracer uptake depending on the histological picture. Nonetheless bone scans are helpful in other asymptomatic lesions.