thalassaemia major, treated with long term subcutaneous desferrioxamine

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1 Iron stte nd heptic disese in ptients with thlssemi mjor, treted with long term subcutneous desferrioxmine J Clin Pthol 1987;4: BEATRIX WONKE,t A V HOFFBRAND,* D M FLYNN,$ M A ALDOURI,* MARTINE LAULICHT,* L A FENTON, P J SCHEUER, C C KIBBLER,tt C A ALLWOOD,tt D BROWN,tt H C THOMAStt From the Deprtments of *Hemtology, tpeditrics, Histopthology, nd ttmedicine, Royl Free Hospitl nd School ofmedicine, London, nd the tdeprtment ofhemtology, Whittington Hospitl, London SUMMARY Liver biopsies were performed on 51 regulrly trnsfused ptients with # thlssemi, ge rnge 5-36 (men 18-6) yers, who hd received regulr subcutneous desferrioxmine (DFX) tretment for periods between one nd eight yers (4 for eight yers). The biopsy specimens were exmined by light microscopy nd immunofluorescence for heptitis B virus surfce nd core ntigens (HBsAg nd HBcAg), nd the iron content ws determined chemiclly. The results were compred with serum ferritin concentrtion nd sprtte trnsminse (AST) ctivity nd with heptitis B virus serology. Biopsy specimens, in which chemicl liver iron hd been determined in 12, were lso vilble from 17 ptients. Men serum ferritin (± SD) hd fllen from 5885 (3245) jg/l to 1638 (976) pg/l in 36 ptients fter eight yers' cheltion, while men (± SD) liver iron concentrtion hd fllen from 2945 (9) yg/1 mg dry weight to 857 (435) jg/1 mg dry weight in 12 of them. All biopsy specimens exmined were negtive for HBs nd HBc ntigens. The presence of histologicl fetures of heptitis ws ssocited with incresed liver iron content, incresed fibrosis, nd with progression of fibrosis between the two biopsies. Procollgen III peptide ws ssyed in 28 ptients but did not correlte with the degree of heptitis, fibrosis, or with chemicl liver iron content. We conclude tht with regulr subcutneous DFX, men concentrtions of serum ferritin nd liver iron re mintined in these ptients t bout five nd 1 times the norml vlue, respectively, nd tht progression of liver dmge is more likely to be due to virl heptitis, presumbly relted to the prenterlly trnsmitted non-a, non-b gents thn to iron overlod. Liver dmge in regulrly trnsfused ptients with f thlssemi mjor results from incresed heptic iron content nd chronic heptitis ssocited with trnsfusion.`1 Regulr cheltion with subcutneous desferrioxmine (DFX) hs been shown to produce negtive iron blnce in these ptients with or without heptitis.6'-1 On the other hnd, heptitis fter trnsfusion remins common compliction which contributes to progressive liver dmge. In this study we performed liver biopsies on 51 such ptients receiving regulr blood trnsfusions who hd lso received subcutneous DFX for periods from one to eight yers to determine the extent of liver dmge nd ssess the vlue of serum ferritin concentrtions nd sprtte trnsminse (AST) ctivity s indi- Accepted for publiction 27 My 1987 ctors of liver iron content nd liver dmge, respectively. We lso investigted possible ssocition between serum concentrtions of procollgen type III peptide synthesis nd liver disese. Ptients nd methods Liver biopsies were performed on 51 ptients (22 femles, 29 mles, ged 8-36 (men 18 6) yers with f thlssemi mjor, who hd received blood trnsfusions every four to five weeks for four to 34 (men 16-5) yers to mintin pre-trnsfusion hemoglobin bove 1-5-l1 g/dl. Forty ptients hd received subcutneous cheltion for eight yers, four for six yers, nd seven for one to five yers. The biopsy ws performed to determine the extent of liver dmge nd liver iron overlod. Informed consent 1353 J Clin Pthol: first published s /jcp on 1 November Downloded from on 19 October 218 by guest. Protected by

2 1354 Aldouri, ws obtined from ech ptient. Thirty four ptients (66 7%) hd received trnsfusions only in the United Kingdom. Most lso received subcutneous cheltion with DFX 4-6 mg/kg on five to six nights ech week. A few poorly complint ptients used infusions less often (two to four times weekly). The biopsies were performed using stndrd Menghini needles, except in two ptients who hd wedge biopsy of the liver when their spleens were removed. There were no complictions relted to the biopsies. Ech biopsy smple ws divided into three prts for determintion of chemicl liver iron content, detection of heptitis B ntigens, nd for histology. The specimens were nlysed for chemicl liver iron using the method described by Brry nd Sherlock'2 (norml rnge pg/1 mg dry weight). The presence of HbsAg nd HBcAg in the biopsy specimens ws investigted using immunofluorescence. Briefly, fresh liver tissue ws snp frozen in OCT embedding compound nd kept in liquid nitrogen until nlysed. Sections (4 tm) were cut on to glss slides, dried under fn for one hour, nd fixed in cold cetone. The sections were wshed in phosphte buffer sline (PBS) nd then for 2 minutes with the pproprite dilutions of murine monoclonl ntibodies to either HBsAg or HBcAg (rised in our lbortories). Norml mouse serum ws used s negtive control. The sections were incubted t room temperture for 3 minutes nd then wshed in PBS for 2 minutes. Fluorescent rbbit ntiserum to mouse immunoglobulin (Dko Ltd, High Wycombe) ws then dded to ech section nd incubted t room temperture for 3 minutes nd mounted under coverslip in 5% glycerol in PBS. They were then viewed under ultrviolet light illumintion on Leitz Dilux 2 microscope. Wonke, Hoffbrnd, Flynn, Lulicht, Fenton, Scheuer, Kibbler, Allwood, Brown, Thoms severe inflmmtory infiltrte nd liver cell dmge. This method of grding ws chosen rther thn the more conventionl clssifiction of chronic persistent nd chronic ctive heptitis, becuse in our experience progression of liver disese in thlssemic ptients seemed to be minly by portl fibrosis nd focl lobulr inflmmtion nd necrosis rther thn by piecemel necrosis, the defining feture of chronic ctive heptitis. Fibrosis ws grded s follows:, no fibrosis; 1, portl expnsion; 2, septum formtion; 3, linking of portl trcts or perilobulr fibrosis; 4, cirrhosis. Serum ferritin ws mesured by immunordiometric ssy'3 before nd during subcutneous cheltion. The norml rnges for our lbortories re ig/l in mles nd ig/l in femles. Serum AST ws mesured throughout the study t HISTOLOGICAL ASSESSMENT The specimens were ssessed on severl occsions by one histopthologist nd finlly reviewed by nother. Smples obtined for histologicl ssessment were dequte in most cses. There ws homogeneous distribution of iron nd inflmmtory cells in both the percutneous nd wedge biopsy specimens., Fibrosis ws lso ssessed. Degree of siderosis in heptocytes, Kupffer cells, nd endothelil cells ws grded from -4, s shown by Perls's stin; grde I representing miniml mounts, nd grde 4 the degree seen in heptocytes in fully developed untreted hemochromtosis. Fetures of heptitis were lso clssified into five grdes: grde, no evidence of heptitis; grde 1, scnty lymphocytic infiltrte; grde 2, obvious inflmmtory cell infiltrte in the portl trcts nd lobules with little or no liver dmge; grde 3, lobulr component nd evidence of liver cell dmge (cidophil bodies or piecemel necrosis); grde 4, intervls of three months or less. Norml vlues re less thn 4 IU/l. Serologicl tests were crried out to determine the heptitis B virus stte of ech ptient. The immunordiometric ssy of Goodll et l'4 for HBsAg ws used. Totl ntibodies to HBsAg, ABcAg, nd HBeAg were mesured using commercilly vilble kits (Abbot Lbortories, Dignostic Division). Procollgen type III peptide is biosynthetic precursor of collgen type III nd ws mesured in serum s possible indictor of the degree of heptic fibrosis in these ptients. The method used ws rdioimmunossy using n RIA-ghost kit (Behringwerke AG, Mrburg, West Germny). Current AST nd serum ferritin results were compred with those before strting subcutneous cheltion. Liver biopsy specimens hd been performed on 17 ptients before cheltion begn, with chemicl liver iron content mesured in 12. Sttisticl nlysis ws crried out by the Kruskl- Wllis nd Mnn-Whitney nlyses for nonprmetric studies compring histologicl nd chemicl results, nd liner regression nlysis for correlting serum ferritin, chemicl liver iron content, nd AST. The Wilcoxon rnk sum test for pired smples ws used to compre chnges in serum ferritin nd chemicl liver iron fter eight yers of cheltion. Results SERUM FERRITIN AND CHEMICAL LIVER IRON All 51 ptients showed rised serum ferritin concentrtions rnging from 34-65, men (SD) 174 (133) pg/l, nd men (SD) chemicl liver iron concentrtions in 44 ptients rnged from 68-65, 139 (1558) pg/i mg dry weight. Only two ptients, both ged 8 yers who hd been chelted from the strt of trnsfusions, hd norml chemicl liver iron concentrtions. J Clin Pthol: first published s /jcp on 1 November Downloded from on 19 October 218 by guest. Protected by

3 Iron stte nd heptic disese in ptients with thlssemi mjor LIVER HISTOLOGY (tble 1) Siderosis Most ptients showed grdes 2 or 3 siderosis in heptocytes, Kupffer, nd endothelil cells; few hd no excessive iron visible; some showed grde 4 siderosis (tble 1). Heptitis All the ptients showed some fetures of heptitis lthough this ws miniml (grde 1) in 21 ptients. None showed grde 4 fetures, but 19 (37%) showed grde 3 fetures. Fibrosis All but six of the ptients showed some increse in fibrosis nd in five cirrhosis ws fully developed. The chemicl liver iron concentrtions of ptients with grdes, 1, or 2 heptocyte siderosis were not significntly different from ech other (fig 1). The chemicl liver iron of ptients with grdes, 1, nd 2 heptocyte siderosis, however, ws significntly less thn tht of ptients with grdes 3 (p = -1) nd 4 (p < 1) heptocyte siderosis. There ws lso significnt difference between the chemicl liver iron of ptients with grdes 3 nd 4 siderosis (p < 4). Heptocyte siderosis correlted slightly better with chemicl liver iron content thn did the degree of endothelil nd Kupffer cell siderosis. In the whole group there ws good correltion between serum ferritin nd chemicl liver iron content (r = -886, p < -1 (fig 2). We found closer correltion between serum ferritin concentrtion nd chemicl liver iron content in ptients with grdes 1 nd 2 heptitis (r = 963) thn in ptients with grde 3 heptitis (r = 775). The men chemicl liver iron content in the ptients with severe (grde 3) heptitis (men 2331) (1818) pg/1 mg dry weight) ws significntly higher thn tht in the group with mild (grdes I nd 2) heptitis (men 95 (1219) yg/1 mg dry weight) (p = 5). Men serum ferritin ws lso higher in the group with severe heptitis (2433 (1512) pg/l) compred with (1429 (1252) jg/l) in the group with mild heptitis (p = -25), but there ws no significnt difference between the two groups in the number of units trnsfused (p > -5) with moderte or severe fibrosis (grdes 2, 3, nd 4) (men ge 2-6 yers) (p = 3) (tble 2). Liver iron content of ptients with miniml fibrosis (grdes, 1) ws significntly less thn in those with severe fibrosis (grdes 3, 4) (p < -3). Liver iron content in ptients with grdes nd 1 fibrosis ws not significntly different from tht of ptients with moderte fibrosis (grde 2) (p > 1) nor ws there difference between ptients with moderte nd severe fibrosis (p > -3) (fig 3). On the other hnd, there ws significnt overll correltion between degree of heptic fibrosis nd the severity of heptitis (X2 = 22-8, p = -1) (fig 4). AST ws rised in 29 (37%) of the 51 ptients. RELATION BETWEEN HEPATIC FIBROSIS AND 1 AGE, CHEMICAL LIVER IRON CONTENT, OR - 4 Heptocytes histologicl siderosis HEPATITIS Ptients with miniml fibrosis (grdes, 1) were Fig 1 Reltion between chemicl nd histologicl liver iron significntly younger (men ge 14-2 yers) thn those content nd heptitis. Tble 1 Grde ofsiderosis, heptitis, ndfibrosis in 5I ptients studied Grde 651 6J 4 cm *i, 35 fi 3 cm 25-2 '3 2 ' Z O Heptitis grde I Heptitis grde 2 * Heptitis grde 3 - Medin..- 8 Liver histology Totl Siderosis: Heptocytes Kupffer cells Endothelil cells Heptitis Fibrosis* *Not evluble in two ptients. J Clin Pthol: first published s /jcp on 1 November Downloded from on 19 October 218 by guest. Protected by

4 1356 Aldouri, Wonke, Hoffbrnd, Flynn, Lulicht, Fenton, Scheuer, Kibbler, Allwood, Brown, Thoms 6-5- x,, 4- Fig 2, 3- E 2 ( Hepiitis grde 1 Heptitis grde 2 * Heptitis grde 3 r =.886 E~~ ~. oo~~~~~~~~~~~~~~o W * *d There were poor correltions between serum AST nd the serum ferritin (r = -283, p =.6) or between serum AST nd liver iron content (r = 136, p = 384). On the other hnd, serum AST correlted well with degree of heptitis ssessed histologiclly in tht ll the ptients with no evidence of heptitis or with grde I heptitis showed norml AST vlues wheres 19 of 3 ptients with moderte or severe heptitis hd rised AST vlues (p < -1) (tble 3). Indeed, nine ptients with grde 3 heptitis showed AST vlues more thn twice the norml rnge for periods longer thn six months. Nevertheless, interestingly, some ptients with moderte or severe heptitis ssessed histologiclly (grdes 2 nd 3) hd norml serum AST vlues. Twenty (39%) of the 51 ptients were serum HbsAb positive, 12 of whom were lso HBcAb positive. Tble 4 shows the reltion between heptitis B virus serology nd histologicl grde of heptitis. Only four of 21 (19%) ptients with grde 1 heptitis Tble 2 4 le JO de e le ol.1.41 le O Liver iron (p,g/loomg dry weight) Reltion between serum ferritin concentrtion nd chemicl liver iron content. were HBsAb positive compred with 16 of 3 (53%) with grdes 2 nd 3 heptitis. Of 34 ptients who received trnsfusions entirely in the United Kingdom, eight (23-5%) hd positive HBsAb or HBcAb, or Tble 3 Reltion ofbnorml serum AST to histologicl grde ofheptitis Heptitis grde No ofptients Abnorml serum AST Tble 4 Reltion between HbsAb nd histologicl evidence ofheptitis Histologicl heptitis grde HBsAb positive HBsAB negtive Reltion ofgrde ofheptic fibrosis to incidence ofsevere heptitis (grde 3) in 49 ptients Fibrosis grde No ofptients Age (yers) rnge (men) No (%) with severe heptitis (14 3) (14) (2 6) 3 (19) (2-6) 1 (63) (2 6) 5 (1) de 7 J Clin Pthol: first published s /jcp on 1 November Downloded from on 19 October 218 by guest. Protected by

5 Previous biopsy specimens performed six to eight yers go were vilble from 17 ptients. In 11 p- Iron stte nd heptic disese in ptients with thlssemi mjor both, compred with 12 (7 6%) of 17 trnsfused outside the United Kingdom in res medium or 65, pnendemic for heptitis B virus (Greece, Cyprus, Middle Est nd Indi). All liver biopsy specimens were negtive for HBs nd HBc ntigens by 6- immunofluorescence. Serum procollgen III peptide concentrtion ws mesured in 28 ptients: it ws c 35- rised in 14 (5%) but did not correlte with degree of cm heptitis, fibrosis, or chemicl liver iron, or with serum AST. 3 FOLLOW UP STUDIES The men serum ferritin concentrtion in 38 ptients hd dropped from 5885 (3245) ug/l to 1638 (976) pg/l (p < '1) fter eight yers' subcutneous DFX cheltion. Men chemicl liver iron content in 12 ptients hd dropped from 2945(9) to 857 (435)pg/1 mg dry weight (p <.1) fter five to eight yers on the sme tretment (fig 5). Abnorml serum AST ws defined s n AST ctivity bove the norml rnge for period of six months t the strt of subcutneous DFX or t the time of this study. The AST ctivity remined norml in 1 (28%) nd hd improved in 18 (5%) of 36 tested. It deteriorted in four (11 %) nd remined bnorml in further four (1 1%), ll eight of whom hd shown severe siderosis nd heptitis (tble 5). Tble 5 AST chnges in reltion to histologicl evidence of heptitis nd siderosis in 36 ptients fter eight yers of subcutneous cheltion AST (norml or improved) ASTbnorml* (28 of36) (8 of36) Heptitis histology Siderosis grde *Abnorml = remined bnorml or becme bnorml. Tble 6 Detils offive ptients with progression offibrosis. 25- CD ow O Heptitis grde 1 3 Hepttis grde 2 * Heptitis grde 3 -Medin o O U O- ~~~ -l Fibrosis grde Fig 3 Reltion between chemicl liver iron content, heptitis, nd severity offibrosis. tients there ws no progression of fibrosis-grde I (n = 1), grde 2 (n = 4), grde 3 (n = 5), nd grde 4 (n = 1); one showed n improvement (from grde 3 to 2) while five showed progression of fibrosis (tble 6). In one of these five (ged 16 yers) the progression ws from grde 1 to 2; three (ged 17, 27, nd 36 yers) progressed to grde 3 from grdes 2, 2, nd 1, respectively, nd one ged 18 yers from grde 3 to 4 (cirrhosis). All these ltter four ptients showed Serumferritin Chemicl liver iron content AST Heptitis Fibrosis Sex Age Dte (pg/l) (g/lgoo mg dry weight) (lu/i) grde grde M F F M M op op 1357 J Clin Pthol: first published s /jcp on 1 November Downloded from on 19 October 218 by guest. Protected by

6 frr 4, o cn3 E CD 4 v> 2. z Mrs Aldouri, Wonke, Hoffbrnd, Flynn, Lulicht, Fenton, Scheuer, Kibbler, Allwood, Brown, Thoms severe heptitis on histologicl exmintionon with pernly one ws Discussion sistently rised serum AST vlues, but o: grossly iron overloded (chemicl liver iron The two importnt cuses of liver dmge in regulrly 3428 jig/l mg dry weight). trnsfused ptients with f thlssemi re iron overlod nd heptitis fter trnsfusion. With regulr iron cheltion tretment the degree of iron overlod ws gretly reduced in most of our ptients, nd in most of them chemicl liver iron content ws less thn 223 jg/1 mg dry weight-the threshold t which fibrosis nd cirrhosis occur in genetic hemochromtosis.15 Men serum ferritin nd liver iron concentrtions were mintined t bout five nd 1 times the norml vlue, respectively. As in previous studies' good correltion ws found between histologicl nd chemicl liver iron ssessment. The finding tht serum ferritin nd chemicl liver iron vlues did not correlte with the ge of ptients my be Ir r-. r-- :7 p T :, '! F- L {severe prtly ttributed to differences in complince of ptients, s some of the oldest ptients hd very low Fig 4 Detils ofhistologicl heptitis grde in reltion to vlues nd vice vers, but it lso suggests tht with fibrosis grde in 49 ptients (miniml = 1, moderte 2, dequte cheltion there is no increse of iron lod severe = 3). with incresing number of trnsfusions, s occurs in unchelted ptients.6 Post-trnsfusion heptitis (due to HB or non-a,.., i- non-b viruses, or combintion) remins mjor problem in these ptients. Severe heptitis ssessed histologiclly strongly correlted with incresed fibrosis in the whole group, nd four of five ptients showed histologicl fetures of severe heptitis where fibrosis incresed while receiving subcutneous desferrioxmine for six to eight yers. A similr observtion ws reported by Mser et l.2 Ptients with severe heptitis lso hd significntly incresed chemicl liver iron content compred with those with moderte or no heptitis, nd this ws more thn could be nticipted from their serum ferritin vlues. De Virgilis et l' lso observed incresed heptic iron content in ptients with thlssemi mjor nd chronic ctive heptitis nd siderosis compred with those with siderosis lone, nd found no correltion of liver iron with number of units trnsfused. The explntion of this higher liver iron content in the fce of heptitis is uncler, but the finding suggests tht -C severe heptitis my contribute to liver dmge by both the chronic inflmmtory process nd by 19 higher liver iron content. Our finding tht liver iron in ptients with severe fibrosis (grdes 3 nd 4) ws significntly higher thn in those with miniml fibrosis (grdes nd 1) my hve resulted from the fct tht most of the ptients with severe fibrosis hd severe heptitis (fig 3). The overll correltion of fibrosis with heptitis ws greter thn it ws with Yer chemicl liver iron content but clerly both fctors Fig 5 Chemicl liver iron chnges in 12 ptientrs receiving (heptitis nd iron overlod) my contribute to the liver dmge. subcutneous desferrioxmine since Rised serum AST lso correlted better with the J Clin Pthol: first published s /jcp on 1 November Downloded from on 19 October 218 by guest. Protected by

7 Iron stte nd heptic disese in ptients with thlssemi mjor 1359 presence of heptitis ssessed histologiclly, thn with This study ws supported by the United Kingdom degree of iron overlod (tble 3), lthough seven of Thlssemi Society. We lso thnk Mrs Jckie eight ptients whose AST ctivity remined bnorml Wilkinson, Mrs Megn Evns, nd Mrs Leel on eight yers' follow up hd both severe heptitis Ghndi for word processing. nd gross iron overlod. Norml AST ctivities, however, did not exclude the presence of severe heptitis. References About 5% of ptients with moderte or severe heptitis hd ntibodies in serum to heptitis B virus components, lthough none hd HBs or HBc ntigens in the liver. These dt indicte previous HBV infection, most probbly cquired by blood trnsfusion.- It seems likely tht continuing heptitis is relted more to non-a, non-b virus infection tht lso stems from blood trnsfusions. Only five of 51 ptients were found to hve fully developed cirrhosis while 16 hd severe fibrosis. The men ge of these 21 ptients ws 26 yers. The incidence of severe fibrosis ws therefore less, nd in n older ge group thn previously reported by Jen et l.3 These uthors studied 86 liver biopsy specimens from ptients in northern Itly in the yers who were receiving intrmusculr desferrioxmine nd subsequently subcutneous desferrioxmine. In our study deteriortion of liver fibrosis seemed to be more relted to heptitis incurred s result of trnsfusion thn to iron overlod. The fct tht ptients with miniml fibrosis were significntly younger thn those with moderte or severe fibrosis my hve been due to the differences in the time excess iron hd been present but lso to the effect of erlier cheltion in the younger group. Interestingly, both ptients with norml liver iron concentrtions strted subcutneous desferrioxmine shortly fter blood trnsfusions begn. In conclusion, erly nd continuous cheltion is clerly effective in decresing liver iron overlod nd delying the onset of iron induced liver dmge in ptients with thlssemi. Prenterlly trnsmitted heptitis, however, seems to be n importnt fctor in the progression of liver cell dmge nd fibrosis. The reson for the ssocition of incresed heptic iron with heptitis found in this study is still unexplined. The serum ferritin concentrtion gve n overll indiction of liver iron content, but in ptients with severe heptitis chnges the serum ferritin ws disproportionlly low. Serum AST ctivity correlted better in this well chelted group with severity of heptitis rther thn with liver iron content. 1 Risdon RA, Brry M, Flynn DM. Trnsfusionl iron overlod: the reltionship between tissue iron concentrtion nd heptic fibrosis in thlssemi. J Pthol 1975;116: Mser G, Jen G, Czzol G, Movkov M. Role of chronic heptitis in development of thlssemi liver disese. Arch Dis Child 1976;51: Jen G, Terzoli S, Muri L, et l. Cirrhosis ssocited with multiple trnsfusions in thlssemi. Arch Dis Child 1984;59: Morni GA, Picentini G, Tenzoli S, Jen G, Mser G. Heptitis B or non-a, non-b virus infection in multitrnsfused thlssemic ptients. Arch Dis Child 1984;59: De Virgilis S, Corncchi G, Snn G, et l. Chronic liver disese in trnsfusion dependent thlssemi. Liver iron quntittion nd distribution. Act Hemtol 1981;65: Brry M, Flynn DM, Letsky EA, Risdon RA. Long term cheltion therpy in thlssemi mjor: Effect on liver iron concentrtion, liver histology nd clinicl progress. Br Med J 1974;2: Hussin MAM, Flynn DM, Green N, Hussein S, Hoffbrnd AV. Subcutneous infusion nd intrmusculr injection of desferrioxmine in ptients with trnsfusionl iron overlod. Lncet 1 976;ii: Propper RD, Cooper B, Rujo RR, et l. Continuous subcutneous dministrtion of desferrioxmine in ptients with iron overlod. N Engl J Med 1977;297: Hoffbrnd AV, Gormn A, Lulicht M, et l. Improvement in iron sttus nd liver function in ptients with trnsfusionl iron overlod with long term subcutneous desferrioxmine. Lncet 1979;i: De Virgilis S, Cossu P, Snn G, et l. Iron cheltion in trnsfusion dependent thlssemi with chronic heptitis. Acd Hemtol 1983;67: Cohen A, Mrtin M, Schwrtz E. Depletion of excess liver iron stores with desferrioxmine. Br J Hemtol 1984;58: Brry M, Sherlock S. Mesurement of liver iron concentrtion in needle biopsy specimen. Lncet 1971;i: Addison GM, Bemish MR, Hles CN, Hodgkins M, Jcobs A, Llewellin P. An immunordiometric ssy for ferritin in the serum of norml subjects nd ptients with iron deficiency nd iron overlod. J Clin Pthol 1972;25: Goodll AH, Meek FL, Wters JA, Miescher GC, Jnossy G, Thoms HC. A rpid one step rdiometric ssy for heptitis B surfce ntigen utilising monoclonl ntibodies. J Immunol Methods 1982;52: Bssett ML, Hllidy SW, Powell LW. Vlue of heptic iron mesurements in erly hemochromtosis nd determintion of the criticl iron level ssocited with fibrosis. Heptology 1986;1 16: Requests for reprints to: Professor AV Hofibrnd, Deprtment of Hemtology, The Royl Free Hospitl, Pond Street, Hmpsted, London NW3 2QG, Englnd. J Clin Pthol: first published s /jcp on 1 November Downloded from on 19 October 218 by guest. Protected by