POSTGRADUATE EDUCATION CORNER

PULMONARY AND CRITICAL CARE PEARLS

A 62-Year-Old Woman With Dyspnea, Leukocytosis, and Diffuse Ground-Glass Opacities

Physical Examination

Vital signs were normal except for mild resting tachycardia with pulse 100 per min. Abdomen was soft, nontender, with hepatosplenomegaly present. Chest had fine inspiratory crackles, no wheezes. Cardiac had a grade 2/6 systolic murmur with the rest of the examination being unremarkable.

Laboratory Findings

Laboratory data were significant for WBC 42,000/μL with metamyelocytes 8,000/μL, hemoglobin 9.5 g/dL, platelet count 319,000/μL, and normal liver function tests. Echocardiogram was unremarkable. Complete pulmonary function testing showed FEV₁/FVC 81%, total lung capacity 2.02 L (44%), and FEV₁ 1.04 L (45%), suggestive of severe restrictive ventilatory defect with no bronchodilator response. The 6-min walk distance was 171 m without oxygen desaturation. Posteroanterior and lateral radiographs

Discussion

Myelofibrosis with myeloid metaplasia is a chronic myeloproliferative disorder caused by the clonal proliferation of pluripotent hematopoietic stem cells. It occurs de novo or secondary to essential thrombocythemia or polycythemia vera. The typical peripheral blood smear reveals a leukoerythroblastic picture with circulating immature WBCs, RBCs, and megakaryocytes. Bone marrow is often fibrotic in these cases. The clinical course results in progression of disease with multiple complications,

Clinical Pearls

• 1.

  Diffuse parenchymal lung disease pattern with underlying hematologic pathology should raise a concern for extramedullary hematopoiesis.

• 2.

  Transbronchial biopsies and BAL may be adequate for establishing a diagnosis along with appropriate clinical and radiologic findings.

• 3.

  Megakaryocyte, myeloid, erythroid precursor cells noticed on BAL or biopsy sample are highly suggestive of this disease entity.

Acknowledgments

Financial/nonfinancial disclosures: The authors have reported to CHEST that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.

Other contributions: This work was performed at the University of Florida, Health Science Center, Jacksonville, Florida.