| • Classic CMV intranuclear inclusions are deep purple, occupy
>50% of the nuclear diameter, have a clear perinuclear zone
and a rim of condensed nuclear chromatin
• In this case the perinuclear clear zone is obliterated by
the large size of the CMV inclusion
• Intracytoplasmic CMV inclusions can be present as small punctate dots(nicely seen in this case) |
| Cytomegalovirus Infection |
| Etiology |
• Cytomegalovirus, beta-group herpesvirus |
| Pathogenesis |
• Viral infection of endothelium and epithelial cells as well as stromal cells • Productive infection results in viral cytopathic changes described below • Endothelial cell damage can lead to vascular injury |
| Epidemiology |
• Widely distributed in normal population where it is acquired sexually, perinatally, in breast milk, intrauterine or by respiratory droplets • Causes asymptomatic or mononucleosis like infection; latent in leukocytes • In immunocompromised patient^s becomes disseminated |
| Clinical |
• May result in perforation • Bloody diarrhea |
| General Gross Description |
• Discrete ulcers when endothelial cell involvement pronounced. • May perforate. |
| General Micro Description |
• Cytopathic changes associated with viral infection and replication include marked cellular enlargement. • Large intranuclear and/or intracytoplasmic eosinophilic inclusions • Intranuclear inclusions occupying >50% of nuclear diameter are diagnostic • Necrosis with endothelial cell involvement |
| Reference |
• Diagnostic Surgical Pathology, 2d edition, Sternberg SS (ed). Philadelphia: Lippincott-Raven,1996, pp. 1335.
|
