Clinical Biochemistry of Domestic Animals (Sixth Edition) - UMK ...

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Chapter | 8 Porphyrins and the Porphyrias
TABLE 8-6 Tissue Porphyrins in Bovine Congenital Erythropoietic Porphyria a
Tissue Uroporphyrins Coproporphyrins Protoporphyrins Total
Bone marrow Tr 162 Tr 1890 Tr 394 Tr 2,396
Bones 6,000 Tr Tr 6,000
Teeth 18,550 Tr Tr 18,550
Spleen 0–10 Tr 342 Tr 60 7–400
Liver 0–Tr 16–340 42–65 66–403
Lung 0–79 0–37 Tr 20 20–130
Kidney 0 Tr 117 5–16 5–133
Lymph node 0 0–40 1–7 1–49
Intestine 0 Tr 65 7–77 18–104
Stomach 0 Tr 58 12–82 12–111
Bile 0–690 112–12,205 0–856 112–13,750
Adrenal 0–6 Tr 202 19–170 19–378
Ovary 0 65 1 66
Testes 0 0 9–14 9–14
Skin 0 0 0 0
Muscle 0 10 30 40
Brain/spinal cord 0 23 57 80
a
Given in micrograms per 100 g of tissue.
anemia in the CEP cow. Excess PROTO IX is commonly
found in iron deficiency, hemolytic anemia, and in lead
poisoning. In iron deficiency, PROTO IX accumulates
because of failure to form hemoglobin, but in CEP, serum
iron is normal or elevated ( Kaneko, 1963 ; Kaneko and
Mattheeuws, 1966 ; Watson et al. , 1959 ). Similarly, PROTO
IX accumulates in lead poisoning because of inhibition of
ferrochelatase and a subsequent inability to insert iron into
hemoglobin.
iv . Tissue The range of concentrations of porphyrins
in the tissues of CEP cattle is given in Table 8-6 . The
deposition of porphyrins throughout the bones and
soft tissues is readily apparent at postmortem of severe
cases by the generalized discoloration. A reddish brown
discoloration is most apparent in the teeth, bones, and bone
marrow. Greatest discoloration of soft tissues occurs in
the lungs and spleen in which characteristic fluorescence
may be observed with UV light. The high concentration of
porphyrins in the spleen is consistent with the hemolytic
type of anemias in CEP. Discoloration of skin, muscle,
heart, liver, and kidney is also observed but only a part is
due to porphyrins. The discoloration is likely due to other
porphyrin derivatives and to hemoglobin staining.
c . Hematology
The hematological picture of the majority of reported
cases is one of a responsive hemolytic anemia. In general,
the degree of response is correlated with the severity
of the hemolytic anemia. The anemia in mild cases of
bovine CEP is normocytic and in the more severe cases is
macrocytic, a reflection of the severity of the hemolysis
and the acuteness of the response. In the severe cases of
bovine CEP, there is reticulocytosis, polychromasia, anisocytosis,
basophilic stippling, and an increase in nucleated
erythrocytes. A consistent monocytosis has been observed
( Kaneko, 1963 ; Rhode and Cornelius, 1958 ), but this
remains unexplained. There is a markedly decreased M:E
ratio in the presence of the anemia, indicating a marked
bone marrow hyperplasia. Bone marrow is also a principal
site of porphyrin deposition, and Watson et al. (1959)
found high concentrations of uroporphyrins in the bone
marrow of a CEP cow.
The presence of porphyrins in the nucleated erythrocytes
is clearly evident by examination of unfixed and
unstained bone marrow smears with a fluorescent microscope.
These fluorescent cells have been called fluorocytes.
This phenomenon was originally observed by Schmid et al .
(1955) in the bone marrow of a human patient and helped