American Journal of Hematology 2:41-46 (1977)

A Family Study of a Patient With Idiopathic Hemochromatosis Aaron Miller, Abraham Zimelman, and Mark J. Brauer Department of Nuclear Medicine and Medical Services, Boston Veterans Administration Hospital and Boston City Hospital and Boston University School of Medicine, Boston, Massachusetts

A family study of a patient with idiopathic hemochromatosis using noninvasive techniques is presented. All 6 of the patient’s asymptomatic children had an increase in transferrin saturation and/or an increase in the absorption of C O ~ ~ . The C057 absorption test was the most sensitive index of family involvement since one of the children had an increase in absorption at a time when transferring saturation was normal. The family data strongly support the hereditary nature of the disorder, with the mode of inheritance not clearly established from the available data.

Key words: hemochromatosis, iron, cobalt

I NT ROD UCT I ON

A number of studies of patients with idiopathic hemochromatosis have revealed functional derangements of iron metabolism in asymptomatic family members (1 -7). For this reason, most workers believe the disease to be due to an inborn error of metabolism (7-10). However, this view has been challenged by some (1 1). Since the mode of in- heritance is not understood, a study of the family of a patient with hemochromatosis using noninvasive techniques is presented. Five of 6 children ranging in age from 6 to 23 years had abnormalities of iron metabolism similar to those in the patient and other cases of hemochromatosis. Involvement of the 6th child was less definitive.

METHODS

Serum Iron and Total Iron Binding Capacity (TIBC)

different serum samples were analyzed for each subject.

Cobalt Absorption

in 0.01 N HC1 and administered to fasting subjects. Subjects under 21 received only 0.2 pCi. Urine was collected for 24 hr and the radioactivity counted as described by Sorbie et al. (13). Normal values were established on 9 healthy male and 3 female subjects ranging in age from 20 to 31 years.

TIBC was determined by the Technicon automated technique (12). At least 2

One mg of CoS7 Clz labeled with 0.5 pCi plus 10 mg of ascorbic acid was dissolved

Received May 24, 1976; accepted November 9, 1976

Address reprint requests to Aaron Miller, M.D., 150 South Huntington Avenue, Boston, MA 02130.

41 0 1977 Alan R. Liss, Inc., 150 Fifth Avenue, New York, NY 10011

42 Miller, Zimelman, and Brauer

Iron Absorption

The fasting patient received 1 mg of FeS04 labeled with 1 pCi of FeS9 together with 10 mg of ascorbic acid dissolved in 0.01 N HCl.

Desferrioxamine (DFO) - Chelatable Iron

This was measured by a total body counter method as described by Price et al. (14).

Ten mg of DFO (Ciba) per kg of body weight was injected intramuscularly, and urine collected for 24 hr. The concentration of iron was determined by an atomic absorp- tion method which will be subsequently described. Normal values were established on 8 healthy males ranging in age from 20 to 40 years.

Iron Stores Mobilized by Phlebotomy

previously described (1 5). Iron stores mobilizable by a weekly phlebotomy of 500 ml was performed as

R ESU LTS

Clinical Data

The propositus was a 52-year-old white male admitted with a 3 month history of diabetes. He drank 1-2 glasses of beer per day. He had received no blood transfusions and had never taken medicinal iron. One cousin had a history of diabetes mellitus. Physical examination revealed grayish color of the skin and a liver palpable 6 cm below the right costal margin.

Laboratory

Alkaline phosphatase 88 Mu/ml, SCOT 60 Mu/ml, and LDH 120 Mu/ml. Fasting blood sugars ranged from 140-200 mg%.

Liver biopsy demonstrated coarse hemosiderin granules in hepatocytes with lesser amounts found in Kupffer cells and in the portal tracts. Some fibrosis was present. The patient was begun on insulin and started on a weekly phlebotomy program. At the present time, serum iron levels have remained elevated despite the removal of 18 gm of iron. Following the removal of 1 gm of iron by phlebotomy, the patient’s Hct rose to 43% and has ranged from 43-46% ever since.

The patient’s wife, father and children were in good health except for the 10-year- old who had suffered from Legg-Perthes disease for 1 year. The patient’s mother had been well all her life when, at age 52, she developed a rapidly progressive fatal illness which was diagnosed as a “tumor of the brain” by a consultant neurologist. The patient’s brother and his 3 children were not available for study but were said to be in good health. Hemoglobin and hematocrits were normal in all the children except for a 10.8 gm% hemoglobin in the 6-yr-old girl. There was no glucosuria and no history of blood loss. Menses were normal for the 16- and the 2 1 -year-old female children. The family ate an average American diet. Iron pots were not used for cooking. There was no history of medicinal iron intake or excessive consumption of alcohol. Analysis of the water drunk by the family revealed no measurable iron.

Laboratory data were as follows: Hbg 11.5 gm%, Hct 39%, Albumin 4.3 gm%.

Idiopathic Hemochromatosis: A Family Study 43

Serum Iron and TIBC

The propositus and 4 of the 6 chldren had very high concentrations of serum iron with transferrin saturations above 80% (Table I). The 6-year-old girl had a minimally elevated serum iron and a saturation of transferrin above 60%. Serum iron and TIBC, when originally measured (2 determinations), was normal in the 10-year-old boy. How- ever, l .5 years later, the TIBC had fallen below normal, with the transferrin saturation now mildly increased (see second footnote to Table I). Serum iron and TIBC were normal in the wife and the father of the propositus.

CoS7 Absorption

CoS7 absorption, as measured by the urinary excretion test, was increased in the propositus (Table I). This was also true of FeS9 absorption, which was equal to 42% (normal range 9-21%). All S of the children tested had unequivocal increases in CoS7 absorption with the actual values comparable to, or greater than, that of the propositus. It should be noted that CoS7 absorption was increased in the 10-year-old boy at a time when his serum iron and TIBC were normal. Absorption in the father and wife of the propositus was normal.

DFO-Chelatable Iron

The amount of iron excreted into the urine after DFO administration was increased in the propositus. It was normal in his wife and in his 12-year-old son, who had the in- creased serum iron and CoS7 absorption (Table I).

The amount of storage iron mobilizable by phlebotomy was determined in the 3 older children. This was equal to 3.5 gm and 2.5 gm in the 2 girls, and 4.0 gm in the 21- year-old boy. These values are clearly in excess of the 690 mg (mean) that can be re- moved from normal males and the 210 mg (mean) from normal females (16).

TABLE I. Parameters of Iron Metabolism in Familv Members of a Patient With Hemochromatosis

Saturation of urinary c~~~ Serum Fe TIBC trans ferrin excretion DFO

Age pg/lOO ml pg/lOO ml (%) (%) mg Fe/24 hr

Father Patient * 'uife Daughter Son Daughter Son

Daughter Normals

Son7

71 70 52 220 41 100 23 217 21 220 16 230 12 220 10 100 6 166

50-160

275 240 246 265 268 280 25 6 280 259

240-420

26 92 40 82 82 82 86 35 64

30-40

24 41 6.6 22 1.2 45 52 49 40 1 .o 42

22$ 0.8$ (16-29) (0.5-1.2)

*The above observations were made 1 month after a series of phlebotomies had removed 4 gm of iron. ?Most recent measurements: serum Fe-110, pg/lOO ml; TIBC-207, pg/lOO ml; saturation of transferrin,

$Mean values. 5 3%.

44 Miller, Zimelman, and Brauer

DISCUSSION

The patient and 5 of his 6 children, ranging in age from 6 to 23 , manifested consistent increases in the concentration of serum iron and in the percent saturation of transferrin. Indeed, the only child who was normal when first studied 1.5 years ago, has now also de- veloped changes in transferrin saturation. Thus, an increase in transferrin saturation, an abnormality seen in the asymptomatic phase of hemochromatosis (8,9), was found in all 6 children. These findings cannot be ascribed to an increased intake of iron or to an ex- cessive exposure to alcohol and can best be explained by a hereditary transmission of the disorder. Also in support of this proposal is the finding of increased Co5’ absorption in the patient and the 5 children so tested. Cobalt has been shown to share a common absorptive pathway with iron, and increased absorption has been found in situations where iron absorption is increased, i.e., from deficiency and hemochromatosis (13, 17, 18). This study corroborates these findings and represents the first use of the cobalt absorption test in a family study of hemochromatosis. Interpretation of the results of the cobalt absorption test in the children is complicated by the fact that our normal values and those of others (13) were obtained on older subjects. Since the levels of cobalt absorption in the children were approximately twice that of the mean of the control groups, it seems likely that the absorption of cobalt was truly increased. Data on the cobalt absorption of normal 10--19- year-old subjects is needed to resolve this question. It should be noted that the 1 child with a normal serum iron had an increased absorption of Co” . Balcerzak et al. have similarly observed increased iron absorption and normal serum iron levels in the asympto- matic children of patients with hemochromatosis (6). This then represents the earliest phase of the disease, one in which iron and cobalt absorption is increased but where the body load of iron is as yet insufficient to elevate serum iron levels. Measurements of iron absorption involve the collection of stools for a number of days or access to a total body counter, whereas that of cobalt absorption can be rapidly performed by any Nuclear Medicine Unit. This makes it ideal for the detection of the initial phase of iron overloading disease, and, together with a measurement of serum and of chelatable and phlebotomy-mobilizable iron, permit a family study of hemochromatosis by noninvasive means. The recently described serum ferritin assay (19) may also prove useful, although it appears to be less sensitive than absorption tests and serum and chelatable iron determinations in the de- tection of the early phase of the disease (20,21).

The family presented is unusual in two respects: (a) the probable involvement of all 6 children; and (b) the early age at which abnormalities of iron metabolism were observed. A review of the literature revealed only 2 other large families where all children were possibly affected. However, the children in these studies were above age 35 and increased alcohol consumption was present in some (3,6). Despite the many family studies of hemochromatotic patients the mode of inheritance remains uncertain. Initial studies suggested transmission by an autosomal dominant gene of variable expressivity and/or penetrance (1,?-, 9). Other data have indicated that the disease results from the inheritance of a pair of autosomal recessive genes with the heterozygote manifesting varying degrees of abnormality (8,9). In view of the divergent data, Crosby has suggested that idiopathic hemochromatosis may not represent a single genetic disorder (22). Unequivocal proof of the mode of inheritance cannot be established from the data on the patient’s family (Fig. 1). The possible involvement of all 6 children is readily explicable if each had inherited 1 recessive mutant gene from their homozygotic father, whereas the probability of this occurring with an autosomal dominant gene would only be 1 in 64. However, the clear absence of any abnormality in the father and the wife of the pospositus, plus the

Idiopathic Hemochromatosis: A Family Study 45

Fig. 1. Pedigree of family with idiopathic hemochromatosis. Squares denote males, circles females. The lower half represents serum iron concentration, the upper half Co5' absorption. Area is lined or dotted when either increased. N indicates untested; the number below the age; the arrow, the propositus; and t dead.

magnitude of the iron overload in the 16-, the 2 1 -, and the 23-year-old children, favor the latter type of an inheritance. The present family study points out the difficulty in establishing the mode of inheritance in hemochromatosis despite the use of laboratory tests which detect the earliest abnormalities of iron metabolism.

predictable occurrence of frank hemochromatosis in juveniles, the degree of iron over- load in the 12-year-old was of clinical concern. Since assessment of iron stores by phlebotomy or liver biopsy were not possible for psychological and technical reasons, the normality of iron stores as measured by DFO was clinically reassuring.

In view of the uncertainty as to the genetic nature of the disease, plus the un-

ACKNOWLEDGMENTS

We wish to thank Mrs. Elisabeth S. Dell and Ms. Regina McLean for their capable technical assistance.

REFERENCES

1. DebrC R, Dreyfus J, FrCzal J, Labie D, Lamy M, Maroteaux P, Schapira F, and Schapira G:

2. Bothwell TH, Cohen I, Abraham L, and Perold SM: A familial study in idiopathic hemochromatosis.

3. Brick IB: Liver histology in six asymptomatic siblings in a family with hemochromatosis; Genetic

4. Johnson GB, and Frey WG: Familial aspects of idiopathic hemochromatosis. JAMA 179:747-

5. Williams R, Scheuer PJ, and Sherlock S: Inheritance of idiopathic hemochromatosis: Clinical

6. Balcerzak SP, Westerman MP, Lee RE, and Doyle AP: Idiopathic hemochromatosis: A study of

7. Lloyd HM, Powell LW, and Thomas J J : Idiopathic hemochromatosis in menstruating women. A

8. Saddi R, Feingold J : H6mchromatose idiopathique. Maladie recessive autosomique. Rev Franc

Genetics of hemochromatosis. Ann Hum Genet 23:16-30, 1958.

Am J Med 27:730-738,1959.

implications. Gastroenterology 40:210-214, 1961.

751,1962.

and liver biopsy study of 16 families. Q J Med 31:249-265, 1962.

three families. Am J Med 40:857-871, 1966.

family study, including the use of diethylene triamine pentaacetic acid. Lancet 2:555-557, 1964.

Etudes Clin et Biol 14:238-251. 1969.

46 Miller, Zimelman, and Brauer

9. Finch SC, Finch CA: Idiopathic hemochromatosis: An iron storage disease. Medicine 34: 381 - 430,1955.

10. Scheinberg HI: The genetics of hemochromatosis. Arch Intern Med 132:126-128, 1973. 11. MacDonald RA: Hemochromatosis: A perlustration. The Am J Clin Nutr 23:592-603, 1970. 12. Giovanniello TJ, DiBenedetto G, Palmer DW, and Peters T Sr: Fully and semi-automated methods

for the determination of serum iron and total iron-binding capacity. J Lab Clin Med 71:874- 883,1968.

13. Sorbie J, Olatunbosun D, Corbett WEN,and Valberg LS: Cobalt excretion test for the assessment ofbody iron stores. Can Med Assoc J 104:777-782,1971.

14. Price DC, Cohn SH, Wasserman LR, Reizenstein PG, and Cronkite EP: The determination of iron absorption and loss by whole body counting. Blood 20:517-531, 1962.

IS. Haskins D, Stevens AR, Jr, Finch SC, and Finch CA: Iron metabolism: Iron stores in man as measured by phlebotomy. J Clin Invest 31:S43-547, 1952.

16. Walters GO, Miller FM, and Worwood M: Serum ferritin concentration and iron stores in normal subjects. J Clin Path 26:770-772, 1973.

17. Pollack S, George JN, Reba RC, Kaufrnan RM, and Crosby W: The absorption of nonferrous metals in iron deficiency. J Clin Invest 44:1470-1473, 1965.

18. Olatunbosun D, Corbett WEN, Ludwig J, and Valberg LS: Alteration of cobalt absorption in portal cirrhosis and idiopathic hemochromatosis. J Lab Clin Med 75:754-762, 1970.

19. Addison GM, Beamish MR, Hales CN, Hodgkins M , Jacobs A, and Llewellin P: An immunoradio- metric assay for ferritin in the serum of normal subjects and patients with iron deficiency and iron overload. J Clin Path 25:326, 1972.

20. Beamish MR, Walker R, Miller F, Worwood M, Jacobs A, Williams R, and Corrigall A: Transferrin iron, chelatable iron and ferritin in idiopathic hemochrornatosis. Brit J Haematol 27: 219-228, 1974.

21. Wands JR, Rowe J A , Mezey SE, Waterbury LA, Wright SR, Halliday JW, Isselbacher K J , and Powell LW: Normal serum ferritin concentration in precirrhosis hemachromatosis. N Engl J Med 19: 302-305,1976,

22. Crosby W H : Hemochromdtosis. Arch Int Med 133:1072, 1974.