Paraspinal soft tissue masses in a patient with a metabolic bone disease

Excerpt

The 49-year-old female patient presented to the emergency department with cough and shortness of breath for a few days. Her chest radiograph demonstrated a right upper lobe consolidation representing pneumonia. Incidentally, she was noted to have a lobulated paraspinal mass in her left hemithorax (Fig. 1). The patient was noted to have a history of pyknodysostosis, multiple related fractures including C1 vertebral body and hearing loss. Prior imaging workup performed included plain film radiography and CT of the face and neck. Plain films of the face and cervical spine revealed an obtuse gonial angle (Fig. 2), a hallmark feature of this entity. Other characteristic changes noted on CT face included calvarial thickening, non-closure of cranial sutures, underpneumatization of sinuses and mastoid air cells, and diffuse sclerosis of the visualized bones. CT of the neck demonstrated bilateral lobulated paraspinal soft tissue masses left larger than right (Fig. 1 *). These findings were consistent with extramedullary hematopoiesis. On further review of her charts, the patient had a history of long-standing fatigue, for which she was being followed by a hematologist. Her most recent hemoglobin (Hgb) was low − 7.1 and so was her platelet count − 95,000. Prior records confirmed that these counts had been low for several years. Her blood smear showed nucleated RBC, metamyelocytes, and myelocytes. Her TSH was elevated at 6.87. Her iron saturation was 22% and ferritin 98. Her Vitamin B12 and folate levels were normal. Her ESR and reticulocyte count were elevated at 46 and 3.1% respectively. There was no hemolysis on her blood smear. Her HIV, HBV and HCV test were normal. On clinical examination, she had hepatosplenomegaly, which was felt to represent additional sites of extramedullary hematopoiesis. In the background of pyknodysostosis, she was suspected to have myelophthisic anemia. Her WBC count had been reported as normal on several occasions and hence was not pancytopenic, and the pneumonia was likely an incidental finding. …