Organohalogen concentrations and a gross and histologic ...

Table 1
Results of histological examination of liver tissue from 88 polar bears sampled in East Greenland, 1999-2002 given as frequencies (no. of
observations in paranthesis). Changes considered were lipid content of Ito-cells (lipid), portal mononuclear cell infiltrations (infiltrations),
lipid granulomes (granulomes), portal fibrosis (fibrosis) and bile duct proliferation (proliferation). Histopathological findings were classified
according to severity (absent, mild and moderate). Sub: subadults of both sexes, AdF: adult females and AdM: adult males. In few cases
of autolysis and freeze damage, one or more of the changes considered could not be evaluated.
Group Lipid Infiltrations Granulomes Fibrosis Proliferation
Absent 41%
(14)
Mild 26%
(9)
Moderate 32%
(11)
148
Sub AdF AdM Sub AdF AdM Sub AdF AdM Sub AdF AdM Sub AdF AdM
10%
(3)
10%
(3)
80%
(23)
0%
(0)
16%
(4)
84%
(21)
3%
(1)
66%
(21)
31%
(10)
8%
(2)
72%
(18)
20%
(5)
21%
(5)
16%
(5)
54% (13) 68%
(21)
25%
(6)
16%
(5)
52%
(13)
36%
(9)
12%
(3)
33%
(8)
54%
(13)
13%
(3)
Mononuclear cell infiltrations and lipid granulomas
The second histological change was focal, mainly portal, mononuclear cell
infiltrations (lymphocytes, macrophages and neutrophils) and in few cases
necrosis (eosinophilic bodies) of individual hepatocytes (chronic multifocal
non-suppurativ hepatitis) (Fig. 2) and 1 case of fibrin exudation (focal acute
hepatitis). In cases with heavy cell infiltrations these were randomly distributed
(disseminated). The degree (absent, mild and moderate) of portal
mononuclear cell infiltrations was not age-related (p>0.4), and did not differ
between subadults and adults (p>0.4, Table 1). Additionally, granulomas
were noted, and frequently containing a central vacuole (lipid granulom) although
the vacuole could represent necrotic heaptocyte as well as lipid. Individual
exhibiting moderate granuloma score were signficant older compared
to individuals having mild granuloma score (p=0.005). There was a
tendency – although not statistically significant - of subadults having a
higher frequency of granulomas than adults (p