Cytomegalovirus is a member of
and contain double-stranded
Description of the
by intra-nuclear inclusion with enlargement of both cell & nucleus. Cytoplasmic inclusions are also seen in the infected cells.
Nuclear inclusion: Single, measuring up to 20 µm in diameter, while the cytoplasmic
inclusions are much smaller, measuring 1 to 3 µm.
It is usually basophilic
but may be eosinophilic, round to oval, with a peripheral halo and
accentuation of the nuclear membrane.
At the edge of the viral inclusion, a
rounded clump of peripheral chromatin may be seen extending into the clear
region of the halo.
Following Ganciclovir therapy, the intranuclear
Cytomegalovirus has been reported to have a globular and eosinophilic
appearance due to loss of viral DNA.
inclusions: Basophilic to amphophilic and indistinct.
Special stain: Cytoplasmic inclusions stain
with the Periodic Acid-Schiff (PAS) and Gomori-Methenamine Silver(GMS)
The intranuclear inclusions are Feulgen positive and contain viral nuclear,
protein, and capsid material.
Cases in which the inclusions are not easy to
recognize or few in number and it is helpful to perform either immunohistochemical staining or in situ
hybridization as a diagnostic aid.
It is common all over the world. 40-100%
adult population is sero-positive.
1. From mother: i) In-uterus (transplacental)
; ii) birth canal secretion-during birth. iii) breast milk
2. From Day-Care-Center through saliva.
3. Commonly from venereal contact,
respiratory secretion & fecal-oral route.
(i) Blood transfusion ;
(ii) Transplant from infected donor ; (iii) Congenital
Mostly asymptomatic, Cytomegalovirus remains latent in
leucocytes (major reservoir). Some produce fatal syndrome, known as
Cytomegalic Inclusion Disease (CID).
Jaundice, petechiae, microcephaly,
thrombocytopenea, diarrhea & Central Nervous System disease.
Liver: Clinicopathological study of liver
involvement in cytomegalovirus infection in infant autopsy cases.
i) Persistence of hepatic hematopoesis. ; ii )P eriportal hepatic necrosis iii)Dense mononuclear infiltrate.
Mostly in immunosuppressed individuals.
Example: i) Organ transplant from seropositive
donor associated with immunosuppressive therapy.
ii) Bone marrow transplant-due to
immunosuppressive therapy & Graft vs Host reaction.
iii) AIDS patients primarily affect Lungs &
Cytomegalovirus can infect a variety of cell types and in the lung
Epithelial cells of
the airways and alveoli ; fibroblasts ; macrophages ; endothelial cells. The cytopathic effects of CMV include both nuclear and cytoplasmic
inclusions. Infected cells show cytomegaly or marked enlargement.
Cytomegalovirus infection of the lung :
pattern: Result from hematogenous spread ; shows multicentric
lesions ; consist of alveolar exudation by fibrin,
inflammatory cells, neutrophils, and chronic inflammatory cells. Centrally -
Lesions may show necrosis, hemorrhage, alveolar fibrin, and inflammatory
Cytomegalovirus inclusions are present in the nodular lesions.
interstitial pneumonitis: Features range from mild to a pattern of
diffuse alveolar damage. There may be interstitial edema, alveolar fibrin,
and hyaline membranes, or interstitial fibroblastic proliferation and type 2 pneumocyte
hyperplasia. Number of
Cytomegalovirus inclusions vary from a few to numerous.
iii) Hemorrhagic pneumonia
inclusions associated with minimal inflammation or lung injury:
frequently occurs in immunocompromised patients.
Combined infection of lung with Cytomegalovirus, is
commonly seen with
Pneumocystis carnii ,
Special techniques help to confirm the presence of multiple organisms,
especially if more than one virus is present .
PubMed links to related abstracts
Cytomegalovirus infection of Gastrointestinal tract patient presents with severe pain, loss of
weight, weakness, remitting fever.
Gastrointestinal lesions are
erosive-ulcerous or ulceronecrotic.
Infection and viral
replication, mostly occurs in ulcerative disease of intestine. Example: Crohns’
disease, Ulcerative colitis.
Inclusions are seen in
endothelial & mucosal cells.
infection in the gastrointestinal tract:
following pathogenetic chain of
infection course in the gastrointestinal tract was established:
microcirculatory disorders -> segmental ischemia -> necrosis with
inflammatory infiltration and CMV transformation of the cells-> fibrosing ->
cicatricial transformation of the organ wall. Some authors have suggested
that developing sclerosis due to
cytomegalovirus involvement of the intestine may
Few cases of
cutaneous involvement have been reported:
Non-specific dermal infiltrate ;
ii) Cells involved include - Endothelial cells in small dermal vessels ;
fibrocytes ; macrophages and rarely ductal epithelial cells.
'Blueberry muffin lesions' seen in congenital infections are due to dermal
1. Demonstration of CMV ; 2. Antiviral
antibody ; 3. PCR- detection of viral genome.