RENALFUNCTION IN WILSON'S DISEASEI

By A. G. BEARN, T. F. YtU, AND A. B. GUTMAN

(From the Rockefeller Institute for Medical Research, and the Departments of Medicine, TheMount Sinai Hospital, and Columbia University College of Physicians and

Surgeons, New York, N. Y.)

(Submitted for publication November 30, 1956; accepted March 7, 1957)

Wilson's disease (hepatolenticular degenera-tion) is an hereditary disorder characterized by avariety of metabolic defects. There is excessiveabsorption of copper from the intestinal tract (1,2) and, as a consequence, an increase in the totalcopper content of the body, particularly in thebrain, liver (3) and kidneys (4). The serumceruloplasmin, the main copper-carrying proteinpresent in the serum, is abnormally low (5, 6).The total serum copper concentration also islower than normal (6, 7), although the smallfraction of copper bound to serum albumin, desig-nated by Cartwright and his co-workers as the"direct-reacting copper," is increased (7). Thereis excessive urinary excretion of copper (8).

The finding of marked aminoaciduria in pa-tients with Wilson's disease by Uzmanand Denny-Brown in 1948 (9) revealed still another meta-bolic abnormality which occurs in many but notall cases (10). There may also be increased uri-nary urate excretion, accompanied by a moderatedecrease in the serum urate level (11). Glycos-uria, in the absence of a raised blood glucose con-centration, is an occasional additional finding(12).

The occurrence of marked aminoaciduria, uri-cosuria and glycosuria in some patients with Wil-son's disease suggests the possibility of renal in-volvement in this disorder (12). Little informa-tion is available concerning the nature and extentof the presumed renal defect (13, 14).

The present investigation was designed to afforda more composite analysis of discrete renal func-tions in Wilson's disease by applying simultaneousclearance techniques. A preliminary report ofsome of the results has appeared elsewhere (15).

1 These studies were supported, in part, by a grant-in-aid (A-162) from the National Institute of Arthritis andMetabolic Diseases, National Institutes of Health.

CASESAND METHODS

The nine patients studied were in varying stages ofthe disease (Table I). The manifestations of the disorderin these patients were predominantly neurological.None gave evidence of advanced cirrhosis of the liverand none had ascites. All of the patients had a de-creased serum ceruloplasmin. In eight of the nine pa-tients the total serum copper excretion was reduced.The urinary copper excretion was excessive in every in-stance. The daily urinary output of a-amino nitrogenwas increased, or an increase could readily be inducedby a high protein intake. All of the patients had re-ceived considerable quantities of BAL medication but thiswas discontinued for at least three days prior to theclearance study.

Eleven renal clearance studies were performed in thesenine patients, using standard techniques (16). The glo-merular filtration rate was measured by inulin clearance;renal plasma flow by clearance of para-aminohippurate;tubular excretory mechanisms in six instances by esti-mation of TmpAH; tubular reabsorptive mechanisms byclearances of amino acids, urate and phosphate, and infour patients also by estimation of Tm glucose. As afurther measure of tubular excretory and reabsorptivecapacities, the inhibiting effect of probenecid on tubulartransport of PAH and urate was studied in seven pa-tients. The excretion of bicarbonate and titratable acidwas determined in four patients.

All experiments were performed in the morning withthe patient in the fasting, post-absorptive state. To en-sure adequate urine flow for the duration of the clearanceexperiments, liberal quantities of water were adminis-tered orally. Three or four urine collections were madeby indwelling catheter in every experiment, each collec-tion comprising a period of 20 minutes; in the experi-ments with probenecid, six 20-minute collections weremade. When the determination of bicarbonate was tobe included in the analysis, the customary air insufflationand bladder wash were omitted, and paraffin oil was usedto prevent loss of CO,. Urine pH determinations weremade by means of a Cambridge pH meter as soon as eachurine sample was procured.

Two patients (Cases Y.R. and LA.) were hospitalized.and maintained on a constant diet of 2,500 calories. Af-ter a control period of six days, ammonium chloride in,syrup of cherry was administered for four successivedays in doses of 10, 14, 14 and 16 Gm. per day, respec-tively. Observations were continued for five days aftercessation of medication. The urine, preserved with tolu-

1107

A. G. BEARN, T. F. YiJ, AND A. B. GUTMAN

TABLE I

General description of the nine cases of Wilson'sDisease studied

Approximate OsteomalaciaName duration or boneSex of overt Clinical fragmen-Age disease severity* tation Albuminurlat

years mg./24 oursM. F. 3 +++ 0 <10Male40

R.V. 4 + 0 <10Male13

M.G. 5 + + 180Male33

C.P. 6 + 0 270Male27

P. C. 7 ++ + <10Female36

F.L. 8 + + 20Male35

L.A. 20 + 0 140MaleS3

Y. R.t 23 ++ +Female37

B.R.t 23 ++ 0 60Female37

* Clinical severity: + Mildly incapacitated but employ-able, + + Severely incapacitated, + + + Bedridden.

t Normal range (10 to 20 mg. per 24 hours).t Uniovular twins.

ene, was collected daily throughout the 15-day period ofstudy and the pH, titratable acid, and bicarbonate weredetermined.

Analytical methods. Inulin, para-aminohippurate, urate,phosphate, ammonia, titratable acid, and creatinine weredetermined by the standard procedures indicated else-where (17). In estimating glucose Tm, samples for inu-lin analysis were digested with baker's yeast before colordevelopment with diphenylamine, instead of the Roemethod employed otherwise for determination of inulin.Glucose was determined by the Folin and Wu method.Plasma a-amino acid nitrogen was estimated by themethod of Hamilton and Van Slyke (18), urinarya-amino acid nitrogen by the method of Van Slyke, Mac-Fadyen, and Hamilton (19). Plasma and urinary bi-carbonate were determined by Van Slyke's manometrictechnique. The urinary excretion of albumin was esti-.mated by an immunological technique (20).

RESULTS

Except in one instance (Case R.V.), the glo-merular filtration rate, as measured by the inulinclearance, was reduced (Table II). The reduc-tion was moderate in Cases M.F., P.C., C.P.,M.G., and F.L. (range, 76.2 to 91.9 ml. per min.),more pronounced in Cases L.A., Y.R., and B.R.(range, 48.9 to 69.0 ml. per min.).

As another indication of glomerular involve-ment, the urinary excretion of albumin was in-creased in Cases C.P., M.G., L.A., and B.R. (270,180, 140, and 60 mg. per 24 hours, respectively).In the remaining four cases, the urinary excretionof albumin was within the normal range (< 10 to20 mg. per 24 hours) by the immunologic methodemployed. The blood urea nitrogen was not ele-vated in any of the patients.

Renal plasma flow, as measured by clearanceof para-aminohippurate, was consistently reduced.In six cases, CpAH ranged from 453 to 342 ml. permin. In two patients (Cases L.A. and Y.R.),CPAHwas less than 250 ml. per min. (Table II).The filtration fraction, CQ.Un/CpAH, was somewhathigher than normal in most instances, with a meanof 0.238. The blood pressure was normal inevery instance.

Tubular excretory capacity, as measured byTmpAH, was invariably reduced in the six patientsexamined (Table II). In four instances (CasesM.F., M.G., L.A., and Y.R.), the values obtainedwere below 40 mg. per min.; in Cases P.C. andF.L., TmPAHwas 59.1 and 43.5 mg. per min.,respectively.

Tubular reabsorptive mechanisms, in respect toa-amino nitrogen, urate, inorganic phosphate andglucose, were found to be impaired (Table II).

The Ca_EN/Cin,1in ratio in six of the nine caseswas considerably increased. The highest valueswere found in the three cases of longest durationof overt disease (L.A., Y.R., and B.R.), in whomCaN.,2N/C,,wjn was 15.8 per cent, 10.0 per centand 16.8 per cent, respectively. (Normal range,1.0 per cent to 3.0 per cent). The plasma a-aminonitrogen in these patients did not differ signifi-cantly from normal.

The plasma urate was less than 3.0 mg. per centin six patients (2.0 mg. per cent in Case B.R.),and in the remainder varied between 3.0 and 3.9mg. per cent-all below the minimum normal level

1108

RENAL FUNCTION IN WILSONS DISEASE

by the analytical method employed. (Normalrange, 4.0 to 6.0 mg. per cent). C,,.% was uni-formly increased, in four instances exceeding 20ml. per min. This increase is even more strikingwhen the reduced glomerular filtration rate istaken into account; the mean Cfrat/Cam, was28.0 per cent, range from 15.4 to 46.7 per cent.

The plasma inorganic phosphate was in thelower range of normal in five of the six cases ex-amined (2.4 to 3.3 mg. per cent) and distinctlyreduced in one instance (Case L.A., 1.5 mg. percent). Phosphate clearance exceeded the normalin each of these six cases, ranging from 18.7 to37.1 ml. per min., with a mean of 25.8 ml. permin. Calculation of the ratio, Cpo4/Cinju, empha-sized the increase in phosphate clearance, the meanvalue obtained being 34.1 per cent.

The fasting blood glucose in the four patients inwhom it was measured (Cases M.G., M.F., F.L.,and C.P.) was at low normal levels (78, 84, 87and 87 mg. per cent, respectively). The glucoseTmwas measured in these four patients. In two,the results obtained were somewhat below thelower limit of the normal range (Cases M.F. andF.L., 272 and 246 mg. per min., respectively).In one instance (Case M.G.), the glucose Tmwasreduced to 184 mg. per min. In Case C.P. thevalue obtained was strikingly low, 95 mg. permin. None of these patients had spontaneous gly-cosuria or hypoglycemia. Occasional spontaneousglycosuria was present in three cases (L.A., B.R.,Y.R.).

Effect of probenecid on tubular transport mecha-nisms (Table III)Probenecid is a potent inhibitor of renal tubu-

lar excretory systems (21), markedly suppressingtubular transport of PAH (17, 22); this effect isless pronounced if the transport mechanisms aredeficient, the diminished effect thus serving as afurther indication of the degree of impairment oftubular excretory mechanisms. In two patientswith clinical manifestations of Wilson's disease ofrelatively short duration (approximately fiveyears), probenecid given intravenously in a dosageof 26 to 32 mg. per Kg. body weight reducedTmpAH significantly, from 59.1 to a minimum of22.6 (Case P.C.) ; and from 39.2 to a minimum of29.5 mg. per min. (Case M.G.). This response

14

4Z)

r.,1)

P..

"I,,

04

Go00 m mA-Zrz A-iE06

NOto k- NO

i|a -., ql -O4U)Ci _u "

" 00 U)

%o ..to .

U) 0 t.* .

e UoroC4 In

u u M C4 V-eqeq04 M0eq.

aU

'00 0%

geel; 4 t: q i 4 i_. V_4 Vl _

I o0 'IC '0 'o O

QN e CMCel; el;qeq

0

F.

0-1

a

U

u

a

'44

'C4

C-44

csi

CN-e an oq

_

*E)O _jX

ECV)e

4s

SU. .

eq~e

_ ~

je 0005+*e .). ..Wje

Id4U)t000%0 4_

r.- 00 U)

od o6 e:~-eq W-

- U) U)

e q- C

'00\0CVl _ e

U) l4t - I- "4 %Oeqi ~4 -4 r.:-%

0.* *

0) C4 -

SU) -00to

0C,I q4 _ to CoN MmmmmeX_ c

.*. 0 U-) Ot-.0 t- " in

c 0% wf- U- .4 '0o NI

Q44* ;0 ;.r-o0mo

:2i04. 6 ; g.4 ...

1109

o.

0

0

00

mm

-H -

to

eq

-H -

-t00C40

eq

0t

6s0

U)

000

0

o.0

0

o,.CV 0'0U-o-H-

eq

eq

~400

eq

4-)0

I._

U

4)

4-.0

0

oe

S

UQ

0. o

> U) C;0

O ) Ce

1._4)

aM4

::cd.0

0 Cer.4)Co

~4Cd

- U)

00

0 C

0

0g

"0L) .

4)

0Cd

*HeE

o" 24,)Q a

.,U ." .-.4

A. G. BEARN, T. F. YU, AND A. B. GUTMAN

4 00 0

C'4

C.C14

UCC4 C.4 m

U) e1 U)

ox -bt-ne_

et0f_t1

X 0o _-'-* t-.. 0

eq. C.4 ".

(N M O 0-0%

CC4 iU q to t- 0% m,,RI .4t - C.4

0-U1)4)

v') u)to w0 Cd

.)r

*% * * * **U) t'

%O~u)t'

o' .- o Toeb ) o

~olOc~Ou)* * * . * * .

co

4)

4)C.

axX0E.0

4)

C.)

'04)j

I..

*)U )

U) 4

0

To

0 E

o 0,0 4)

o 4)U)

0o

I-

t. 0

a ..U; I.:.

Cef

* o

was somewhat less marked, however, than that ofa normal subject in whomprobenecid in oral dos-age of 20 mg. per Kg. body weight reduced TmpAfrom 83.4 to 26.4 mg. per min. (17). In two pa-tients with symptoms of some 20 years' duration(Cases L.A. and Y.R.: TmpA 14.5 and 21.5mg. per min., respectively), probenecid elicited, atmost, an equivocal further depression of Tmpsm.In three patients (Cases M.F., R.V., and F.L.),whose clinical symptoms were of relatively shortduration, and whose initial CpAH was but moder-ately reduced (422, 453, 341 ml. per min.), therewas marked further suppression of CPAHby pro-benecid. The response did not seem to differin degree from that of (gouty) subjects with in-tact kidney function (17).

Probenecid markedly suppresses tubular reab-sorption of urate and thus increases urate clear-ance in the intact kidney. In 10 gouty subjectswith little or no renal damage, probenecid in oraldosage of 20 to 30 mg. per Kg. body weightevoked an increase in Curte of approximately 300per cent, from a mean of 8.5 ml. per min. to peakvalues averaging 32.9 ml. per min. (range, 10.2 to51.3 ml. per min.) (17). In the seven patientswith Wilson's disease examined, there was an in-crease in Cra,,te of approximately 75 per cent afterintravenous administration of probenecid in com-parable dosage, from a mean of 20 ml. per min.to a mean peak of 35.6 ml. per min. This poorpercentile response is attributable in part to thehigh initial Curate. The results in the two patientswith symptoms of longest duration (Cases L.A.and Y.R.), in whom Curate increased from 18.7 toa peak of only 24.1 ml. per min. and from 16.2 to23.4 ml. per min., respectively, suggest deficienttubular response to probenecid. The findings inthese two patients were comparable to those ob-tained in the Fanconi syndrome, in which therewas no response to probenecid (17, 23).

Effect of ammonium chloride acidosis

It was observed in the course of the foregoingrenal clearance studies that the urine pH rangedfrom 6.6 to 8.0 (Tables II and IV). Thisprompted measurement of urinary bicarbonate ex-cretion which, in the four patients studied (CasesM.F., M.G., C.P., and F.L.), was found to varyfrom 0.088 to 0.034 mMper min. at levels ofplasma bicarbonate ranging from 25.0 to 20.7 mM

1110

I.1-1u

I

II-

0A1

c

' X

3 0

I2 I >

0

o

r.

01a A

M

0

u

.I"

QI"

ce

4)a

'0

0-

a,

I.)

P 4 )-

W4)i

011

04

:9 04 4; . a; i --.

RENAL FUNCTION IN WILSONS DISEASE

TABLE IV

Bicarbonate eretion i#tfeur pants wilk Wilson't Dis;ede

Urine Plasma Urine Urine Urine BHCO ,. BHCOs- BHCQO BICOsName flow Cmi BHCOs pH BHCOs H+ filtered reabsorbed reabsorbed

(ml./min.) (nIL/mis.) (mM/L.) (mM/mis.) (M/mis.) (MM/miS.) (mM/mis.) (mMJ1(M0mWuipuerauiarSe)M. F. 9.8-16.1 90.5 25.0 6.8-7.1 0.088 0.002 2.26 2.17 2.50 2.40F. L. 3.2-14.1 83.2 20.7 6.9-7.0 0.046 0.013 1.72 1.67 2.07 2.01C. P. 5.8- 9.4 85.7 22.0 7.0 0.062 0.010 1.89 1.83 2.20 2.14M. G. 4.0- 9.3 79.0 22.0 6.8 0.034 0.010 1.74 1.71 2.20 2.16

per L. The results (Table IV) suggest that tu-bular reabsorption of bicarbonate may not be quiteas efficient in some patients with Wilson's dis-ease as in the normal subject.

Ammonium chloride acidosis was produced inPatients Y.R. and L.A. In the six-day controlperiod, Case Y.R., in whom overt Wilson's dis-ease was of longest duration, excreted 18.8 to 26.4mMbicarbonate per day (mean, 21.7 mMperday) at a mean plasma bicarbonate level of 23.1mMper L. The urine pH varied from 6.9 to 7.2,the titratable acid averaged 4.4 mEq. per day.With induction of acidosis (plasma bicarbonatereduced to a minimum of 14.6 mMper L.), theurine pH fell to a low of 4.9, the titratable acidincreased to a maximum of 38.0 mEq. per day, bi-carbonate disappeared from the urine.

A similar response was noted in Case L.A. Inthe six-day control period, the excretion of bi-carbonate varied from 11.1 to 16.5 mMper day(mean, 14.1 mMper day) at a mean plasma bi-carbonate level of 27.6 mMper L. The range ofurine pH was 6.2 to 7.0, the titratable acid aver-

aged 11.7 mEq. per day. Administration of am-

monium chloride reduced the plasma bicarbonatelevel to a minimum of 19.1 mMper L. and theurine pH to a low of 5.1. The titratable acid in-creased to a maximum of 41.9 mEq. per day, uri-nary bicarbonate excretion became negligible.

The urinary excretion of ammonia in CasesY.R. and L.A. was within normal limits (means,25.2 and 22.7 mEq. per day, respectively) in thecontrol period.

DISCUSSION

The results of these renal clearance studies con-

firm and amplify previous reports indicating im-pairment of tubular transport systems and renalhemodynamics in patients with Wilson's disease,

at least in its more advanced stages. Somehither-to unrecorded abnormalities are described.

Hodges and co-workers (13, 14) noted markedand consistent reduction in CPAH 'and equivocaldecline in Cow in their study of four cases ofWilson's disease. The present investigation cor-roborates the substantial reduction in renal plasmaflow and discloses distinctly decreased glomerularfiltration rate in most instances. The degree ofimpairment seemed roughly to parallel the severityor duration of overt disease in this series of pa-tients, suggesting progressive deterioration of therenal vascular bed.

The tubular secretory capacity, as measured byTmpsm, was found to be reduced, strikingly so inthe more advanced cases. Associated with thisdecline was a diminishing effect of probenecid ineliciting a further reduction in TmpA.

Impairment of renal tubular reabsorptive ac-tivities in Wilson's disease has been suspected forsome time. The excessive aminoaciduria, for ex-ample, has been attributed to inadequate tubularreabsorption (12, 24). This interpretation is sup-ported by the high values obtained for CO.NHEN,and particularly for C _NH2-.N/Ctuinj in the face ofnormal plama levels of a-amino nitrogen. Simi-larly, diminished tubular reabsorption of filteredurate, suggested by Bishop, Zimdahl, and Talbott(11) and Mahoney, Sandberg, Gubler, Cart-wright, and Wintrobe (25), to explain the uri-cosuria and low plasma urate levels noted by themin patients with Wilson's disease, is indicated bythe augmented urate clearance ratios consistentlyobserved in the present study. The capacity ofprobenecid further to increase Cmt./Ci,.1l de-creased as the tubular transport systems for uratedeteriorated with progress of the disease, until thedrug finally was quite ineffective, as in the Fan-coni syndrome.

1111

A. G. BEARN, T. F. YU, AND A. B. GUTMAN

In all six of the patients so studied, an increasein Cpoo was observed, and in five of these the se-rum inorganic phosphate was in the low normalrange or reduced. Cooper, Eckhardt, Faloon, andDavidson (12) described a patient with Wilson'sdisease who was reputed to have had hypophos-phatemia prior to their study. Warnock (26)reported a patient with Wilson's disease with spon-taneous fractures, demineralization of bone, and aplasma inorganic phosphate level of 2.5 mg. percent. The low serum phosphate and increasedrenal clearance of phosphate may be responsible,in part, for the occasional occurrence of osteo-malacia in this disease (12, 26, 27).

The observation that glycosuria may be presentin some patients with Wilson's disease has beensomewhat amplified, in the present study, in whichthe tubular reabsorptive capacity for glucose wasmeasured. It is noteworthy that, although spon-taneous glycosuria was not usually present, themaximum tubular capacity to reabsorb glucosewas reduced in varying degree in all four casesstudied. These findings emphasize the fact thatfailure to find increased urinary excretion of glu-cose in Wilson's disease does not preclude a veryconsiderable defect in the capacity of the renaltubules to transport glucose across the tubularepithelium.

The tendency to excrete urine of high pH, dueto renal excretion of small quantities of bicarbo-nate at plasma bicarbonate levels which shouldnot be associated with urinary loss (28), sug-gests that there may be slight impairment of tu-bular reabsorption of bicarbonate in advancedstages of Wilson's disease. When ammoniumchloride acidosis was induced, there was a promptdecline in urine pH, increase in titratable acidity,and disappearance of urinary bicarbonate.

The precise mechanisms involved in the impair-ment of tubular functions observed in Wilson'sdisease must remain speculative so long as thenormal mechanisms of renal tubular transportare poorly understood (29). The hypothesis thatthe renal lesion is a primary effect of the abnormalgene on the functional integrity of the renal tubulereceives little support from this study. That theabnormal gene may result in an anatomical de-fect of the renal tubule, not necessarily related tothe described functional abnormalities, is sug-gested by the preliminary observations of Soothill

and Kark (30). They have observed a deformityin the proximal convolution of the tubule in renalbiopsy specimens obtained from patients withWilson's disease. It was not apparent to themwhether this abnormality was primary, as in theFanconi syndrome, or whether this was due to alocal change resulting from Wilson's disease. Dar-mady (31), however, was unable to discern anyanatomical defect in the proximal renal tubules inthe kidneys of patients who had died of Wilson'sdisease. But although the details of the pathogene-sis of the disease and its varied manifestations re-main largely unknown, a plausible hypothesis toexplain the renal lesions can be tentatively sug-gested as a result of this study. The deficiency ofserum ceruloplasmin in Wilson's disease is as-sociated with an increase in the copper looselybound to serum albumin. This loosely boundcopper can be deposited in any tissue where thereare substances which can compete successfullywith albumin for the copper ion. With increaseddeposition of copper in the kidney, the metal mayinterfere with essential enzyme systems responsi-ble for the transport of materials across the tubu-lar epithelium, such as is presumed to occur inchronic poisoning with other divalent metals (32).Initially, the brunt of the damage falls predomi-nantly on the proximal renal tubule, resulting indefective transport of PAH, phosphate, urate,amino acids, and glucose, in these respects re-sembling somewhat the defects occurring in Fan-coni syndrome. This emphasizes the desirabilityof excluding Wilson's disease in patients with de-fective renal tubular functions.

With progression of the renal lesion, otherfunctions of the kidney are disturbed and thefunctional abnormality is no longer restricted toany anatomical segment of the renal tubule. Adecreased glomerular filtration rate, and a tend-ency to excrete an alkaline urine, indicate morewidespread renal damage.

SUMMARY

1. Eleven renal clearance studies were carriedout in nine patients with Wilson's disease in vari-ous stages of the disorder.

2. The inulin clearance was below the lowerlimits of normal in eight patients. CPAH wasdecreased in every instance.

1112

RENAL FUNCTION IN WILSON'S DISEASE

3. Tubular secretory capacity, as measured byTmpAH, was reduced in the six patients examined.When TmPAHwas very low, probenecid elicitedlittle further decrease.

4. Tubular reabsorption of a-amino nitrogen,urate, phosphate, and glucose was defective, asindicated by the generally increased clearance ra-tios. Serum inorganic phosphate levels were inthe lower range of normal or reduced, and may ac-count for the osteomalacia occasionally encoun-tered in Wilson's disease. The blood glucose wasin the low normal range. The Tmglucose tendedto be low in the four patients so studied, prob-ably explaining the occasional glycosuria in thisdisorder. Serum urate levels were consistentlylow. Probenecid elicited a uricosuric response inmost instances but this was least pronounced inthose subjects who initially had the most impairedtubular reabsorption of urate.

5. The urine pH tended to be more alkalinethan normal, owing to slight urinary excretion ofbicarbonate at plasma bicarbonate levels not ordi-narily associated with renal loss of bicarbonate.The response of two subjects to ammonium chlo-ride-induced acidosis was essentially normal in re-spect to mechanisms for acidification of the urine.

6. The results indicate progressive deteriorationof certain discrete tubular functions, and also ofglomerular filtration and renal plasma flow, withadvance of the disease. It is suggested that theserenal changes may reasonably be ascribed to thedeleterious effects of the accumulation of copperin the kidneys; such effects are known to accom-pany the deposition of other heavy metals in thisorgan. In this view the renal abnormalities de-scribed are secondary to a disturbance in coppermetabolism rather than a direct consequence of theabnormal gene on renal function.

ACKNOWLEDGMENTS

It is a pleasure to acknowledge the assistance of Dr.Arnold B. Ritterband in some of the renal clearancestudies, and the help of the several consultants fromwhom advice was sought.

REFERENCES

1. Bush, J. A., Mahoney, J. P., Markowitz, H., Gubler,C. J., Cartwright, G. E., and Wintrobe, M. M.,Studies on copper metabolism. XVI. Radioactivecopper studies in normal subjects and in patients

with hepatolenticular degeneration. J. Clin. In-vest., 1955, 34, 1766.

2. Matthews, W. B., The absorption and excretion ofradiocopper in hepato-lenticular degeneration (Wil-son's disease). J. Neurol., Neurosurg., & Psy-chiat., 1954, 17, 242.

3. Cumings, J. N., The copper and iron content ofbrain and liver in the normal and in hepato-len-ticular degeneration. Brain, 1948, 71, 410.

4. Wintrobe, M. M., Cartwright, G. E., Hodges, R. E.,Gubler, C. J., Mahoney, J. P., Daum, K., and Bean,W. B., Copper metabolism in Wilson's disease.Tr. A. Am. Physicians, 1954, 67, 232.

5. Scheinberg, I. H., and Gitlin, D., Deficiency of ceru-loplasmin in patients with hepatolenticular de-generation (Wilson's disease). Science, 1952, 116,484.

6. Beam, A. G., and Kunkel, H. G., Abnormalities ofcopper metabolism in Wilson's disease and theirrelationship to the aminoaciduria. J. Chin. Invest.,1954, 33, 400.

7. Cartwright, G. E., Hodges, R. E., Gubler, C. 3.,Mahoney, J. P., Daum, K., Wintrobe, M. M., andBean, W. B., Studies on copper metabolism. XIII.Hepatolenticular degeneration. J. Clin. Invest.,1954, 33, 1487.

8. Mandelbrote, B. M., Stanier, M. W., Thompson, R.H. S., and Thurston, M. N., Studies on coppermetabolism in demyelinating diseases of the cen-tral nervous system. Brain, 1948, 71, 212.

9. Uzman, L., and Denny-Brown, D., Amino-aciduriain hepato-lenticular degeneration (Wilson's dis-ease). Am. J. M. Sc., 1948, 215, 599.

10. Stein, W. H., Beam, A. G., and Moore, S., Theamino acid content of the blood and urine in Wil-son's disease. J. Clin. Invest., 1954, 33, 410.

11. Bishop, C., Zimdahl, W. T., and Talbott, J. H., Uricacid in two patients with Wilson's disease (hepato-lenticular degeneration). Proc. Soc. Exper. Biol.& Med., 1954, 86, 440.

12. Cooper, A. M., Eckhardt, R. D., Faloon, W. W., andDavidson, C. S., Investigation of the aminoacid-uria in Wilson's disease (hepatolenticular degener-ation): demonstration of a defect in renal function.J. Clin. Invest., 1950, 29, 265.

13. Hodges, R. E., Kirkendall, W. M., Schwartz, C., andWild, J. B., Some aspects of kidney function inhepatolenticular degeneration (Wilson's disease).J. Clin. Invest., 1954, 33, 942.

14. Hodges, R. E., Kirkendall, W. M., and Gubler, C. 3.,Some aspects of kidney function in hepatolenticulardegeneration (Wilson's disease). J. Lab. & Clin.Med., 1956, 47, 337.

15. Beam, A. G., Yu, T. F., Ritterband, A. B., and Gut-man, A. B., Renal clearance studies in Wilson'sdisease. Federation Proc., 1956, 15, 12.

16. Goldring, W., and Chasis, H., Hypertension and Hy-pertensive Disease. New York, The Common-wealth Fund, 1944.

1113

A. G. BEARN, T. F. YU, AND AX B. GUTMAN

17. Sirota, J. H., Yii, T. F., and Gutman, A. B., Effectof benemid (p-[di-n-propylsulfamyll-benzoic acid)on urate clearance and other discrete renal func-tions in gouty subjects. J. Clin.-Invest., 1952, 31,692.

18. Hamilton, P. B., and Van- Slyke, D. D., The gaso-metric determination of free amino acids in bloodfiltrates by the ninhydrin-carbon dioxide method.J. Biol. Chen., 1943, 150, 231.

19. Van Slyke, D. D., MacFadyen, D. A., and Hamilton,P. B., The gasometric determination of aminoacids in urine by the ninhydrin-carbon dioxidemethod. J. Biol. Chem., 1943, 150, 251.

20. Kunkel, H. G., Unpublished data.21. Beyer, K. H., Functional characteristics of renal

transport mechanisms. Pharmacol. Rev., 1950, 2,227.

22. Beyer, K. H., Russo, H. F., Tillson, E. K., Miller,A. K., Verwey, W. F., and Gass, S. R., "Bene-mid," p- (di-n-propylsulfamyl) -benzoic acid: itsrenal affinity and its elimination. Am. J. Physiol.,1951, 166, 625.

23. Sirota, J. H., and Hamerman, D., Renal functionstudies in an adult subject with the Fanconi syn-drome. Am. J. Med., 1954, 16, 138.

24. Matthews, W. B., Milne, M. S., and Bell, M., Themetabolic disorder in hepato-lenticular degenera-tion. Quart. J. Med., 1952, n.s., 21, 425.

25. Mahoney, J.. P., Sandberg, A. A., Gubler, C. J.,Cartwright, G. E., and Wintrobe, M. M., Uric acidmetabolism in hepatolenticular degeneration. Proc.Soc. Exper. Biol. & Med., 1955, 88, 427.

26. Warnock, C. G., Hepatolenticular degeneration (Wil-son's disease); a report of five cases, with com-mentary. Ulster M. J., 1952, 21, 155.

27. Luthy, F., tber die hepato-lentikulare Degenera-tion (Wilson-Westphal-Striimpell). Deut. Ztschr.Nervenh., 1931, 123, 101.

28. Pitts, R. F., Ayer, J. L., and Schiess, W. A., The re-nal regulation of acid-base balance in man. III.The reabsorption and excretion of bicarbonate.J. Clin. Invest., 1949, 28, 35.

29. Combined Staff Clinic: Disorders of renal tubularfunction. Am. J. Med., 1956, 20, 448.

30. Soothill, J. F., and Kark, R. M., Personal Communi-cation, 1956.

31. Darmady, E. M., Renal lesions in relation to amino-aciduria and water diuresis. Ciba Foundation Sym-posium on the Kidney, Boston, Little, Brown andCompany, 1954, p. 27.

32. Wallis, L. A., and Engle, R. L., Jr., The adult Fan-coni syndrome. II. Review of eighteen cases.Am. J. Med., 1957, 22, 13.

33. Smith, H. W., The Kidney: Structure and Functionin Health and Disease. New York, Oxford Uni-versity Press, 1951.

1114