Disseminated tuberculosis masquerading primary myelodysplastic syndrome

Tuberculosis is notoriously known to be a great mimicker of other diseases and may cause various haematologic abnormalities, especially with marrow involvement. A 61-year-old man who presented with right empyema and pancytopenia was diagnosed to have disseminated tuberculosis supported by the presence of caseating granuloma with Langhan's giant cells in the marrow and demonstration of acid-fast bacilli in the pleural fluid. Trilineage dysplasia from marrow aspirate was initially attributed to be reactive to the infection. A cytogenetic study was repeated after he showed poor response to a year of anti-tuberculosis treatment. The underlying primary myelodysplastic syndrome was unmasked when his cytogenetics showed trisomy 8. This case report has demonstrated the various haematological manifestations of tuberculosis and highlighted the importance of cytogenetic study in differentiating between primary and secondary myelodysplastic marrow changes.