articles are used for each patient and the amounts

Transcription

1 CLCUM ND PHOSPHORUS METBOLSM N DSESES OF THE THYROPRTHYROD PPRTUS.. CLCUM ND PHOS- PHORUS BLNCE () FOLLOWNG THERPEUTC RD- TON OF THE HYPERPLSTC THYROD GLND, ND (B) N HYPERTHYRODC PTENTS TRETED WTH ODNE By DR. F. S. HNSMN, WTH STTSTCL NLYSS BY DR. W.. CRR FRSER 2 (From the Deprtment of Biochemistry, Royl Prince lfred Hospitl, Sydney, ustrli) n previous publiction () the detils of series of experiments on seven ptients suffering from hyperthyroidism, two of whom hd n ssocited hypoprthyroidism, were given. The following conclusions were drwn: Seven ptients suffering from hyperthyroidism hve been crefully studied. n nlysis of their experimentl dt provides definite evidence in fvour of n ssocited hyperprthyroidism being the direct cuse of the excessive mobiliztion nd excretion of clcium nd phosphorus. Two ptients suffering from hyperthyroidism with n ssocited hypoprthyroidism were studied. Both ptients were in clcium nd phosphorus equilibrium. Though hyperthyroidism is frequently ccompnied by negtive clcium nd phosphorus blnce, it is not invribly so. t is possible for clcium nd phosphorus equilibrium or positive clcium nd phosphorus blnce to be present. Hyperthyroidism per se his no specific effect on clcium nd phosphorus metbolism. (Received for publiction October 2, 937) The present study presents further evidence tht in hyperthyroidism the stte of the clcium nd phosphorus blnce is independent of the mount of circulting thyroxin nd demonstrtes tht severl months subsequent to rdition of the hyperplstic thyroid glnd the clcium nd phosphorus blnce becomes positive though the clinicl nd lbortory evidences of hyperthyroidism re still present. This study ws primrily undertken with three objectives: () To see if the informtion obtined by estimting the clcium nd phosphorus blnce for one period of four dys would be of vlue in the tretment of hyperthyroidism. Senior Honorry in the Deprtnent of Biochemistry, Royl Prince lfred Hospitl, Sydney. 2Fellow Royl Sttisticl Society, London; Sttist, Commonwelth dvisory Council on Nutrition, University of Sydney. (2) To try to correlte the signs nd symptoms of hyperthyroidism with the stte of clcium nd phosphorus blnce; it ws thought tht the degree of so-clled " symptheticotoni " present in ny individul cse my be proportionl to the negtive clcium nd phosphorus blnce. (3) To scertin the clcium nd phosphorus blnce t vrious periods fter rdition of the hyperplstic thyroid glnd. The prcticl vlue of estimting the clcium nd phosphorus blnce for period of four dys The sme experimentl diet ws employed s tht used formerly (). n this diet the sme rticles re used for ech ptient nd the mounts of ech rticle of the diet re incresed or decresed proportionlly; in this wy constnt clorie-nitrogen-clcium-phosphorus rtio is mintined. The cloric requirements of ech ptient re scertined from the bsl metbolic rte nd from the ppetite of the ptient, nd preliminry four dys re used to stbilize the ptient on the diet before the ctul period begins. 25- clorie diet contined pproximtely 6 grms of nitrogen, pproximtely.45 grm of clcium nd pproximtely.88 grm of phosphorus. 3- clorie diet contined six-fifths of these mounts, 2-clorie diet four-fifths, etc. The mounts of clcium nd phosphorus ctully present were estimted for ech period. The nitrogen content ws tken s the verge of lrge number of periods of the previous study. t is known tht fluctutions in the clcium nd phosphorus blnce my be considerble in consecutive periods, but the fluctutions re not so gret tht ptient would hve gross negtive blnce in one period nd be in clcium nd phophorus equilibrium in nother. From our results we consider tht 543

2 544 for clinicl purposes where lrge number of ptients re to be studied one period my be considered dequte to give fir ide of the stte of the clcium nd phosphorus blnce, provided the ptient is in nitrogen equilibrium. F. S. HNSMN ND W.. CRR FRSER The correltion of the stte of the clcium nd phosphorus blnce with the signs nd symptoms of the individul ptient The ttempt to give quntittive vlues to signs such s exophthlmos, tremor, hypotonus nd degree of nervous instbility, by using plus nd minus signs, ws unsuccessful. Ech ptient ws exmined independently by three physicins of the Senior Honorry Medicl Stff, but the physicl signs of the ptients were not constnt. Fctors influencing the stte of the ptient were: () Time of dy the exmintion ws mde. n generl the ptients were much more composed in the morning thn t the end of the dy, but it ws not prcticble to hve the exmintions lwys t stndrd time. (2) Unexplined vritions in the ptient from dy to dy. (3) Visitors. The ptient's signs tended to become exggerted following the effort of entertining reltives nd friends. (4) Different responses of the individul to the personlity of the three exminers. The sme exminer would pprently compose one ptient nd upset nother. The sister-inchrge of the cses frequently remrked on this phenomenon. s we were unble to develop stisfctory technique to give stndrdized findings, this spect of the study will not be further considered. Clcium nd phosphorus blnce () following therpeutic rdition of the hyperplstic thyroid glnd, nd (b) in hyperthyroidic ptients treted weith iodine This pper gives the results of studies on the clcium nd phosphorus blnce of twenty-seven ptients suffering from hyperthyroidism. The ptients re divided into four groups: Group.-Five ptients exmined before ny tretment for hyperthyroidism. Group 2.-Six ptients exmined while iodine ws being dministered. Group 3.-Twelve ptients exmined fter therpeutic rdition of the thyroid glnd. Group 4.-Four ptients exmined before nd fter therpeutic rdition of the thyroid glnd. Group. Cses exmined before tretment (5 cses) Cses nd were in definite negtive clcium nd phosphorus blnce. Both were subsequently operted on, nd the histology of the tumors removed showed diffuse hyperplsi. Cse ws in slight negtive clcium blnce but in positive phosphorus blnce. Cse V ws pproximtely in clcium nd phosphorus equilibrium. Cse V ws in definite negtive clcium blnce nd in pproximte phosphorus equilibrium. This ptient hd n extremely lrge goiter. t consisted of multiple denomt, some of which showed definite hyperplsi. Soon fter the experimentl period the ptient died. The postmortem findings of the thyroid re shown in the protocol. The size of the tumor cn be judged from its weight (59 grms). The bsl metbolism of the ptients in this group t the time of the exmintion rnged from + 6 to + 6 per cent, but there ws no reltionship between the level of the bsl metbolism nd the stte of the clcium nd phosphorus blnce. This cn be seen by referring to Figure, in which the bsl metbolic rte nd the clcium blnce re shown. Group 2. Ptients exmined while on iodine therpy (6 cses) Of these, Cses,,, nd V were in definite negtive clcium nd phosphorus blnce. Cse V ws in slight negtive clcium nd phosphorus blnce. Cse V ws prcticlly in clcium nd phosphorus equilibrium. Cse showed typicl hyperplstic thyroid histologiclly, while the tissue removed t opertion in Cses V nd V hd multiple denomt ssocited with hyperplsi (histologiclly) of the denomtous tissue. n this group lso there ws no reltionship between the level of the bsl metbolism t the time of the experimentl period nd the extent of the negtive clcium blnce (see Figure 2).

3 BMR.-C 4dy penod +3o FiQt CLCUM ND PHOSPHORUS METBOLSM Fi 2 Fit4 3 Fi 4, 4 + x Y +4 x *t'(wper sg. moire per hour) X(cs.per sq.metre per hovt) 545 X=BefWo rditiofn of thyr Y= ftr' it to C blnce Shwn thus BMR. Shewn thu-s FGURES To 4 Figures, 2, 3, nd 4 correspond to Groups, 2, 3, nd 4 respectively. These figures show the stte of the clcium blnce nd the level of the bsl metbolic rte (during experimentl period) on the sme ordinte. The cses re chrted in descending order of negtive clcium blnce. n Figure 4, in the lst cse, the results re expressed s clories per squre meter per hour. n Cse V the iodine ws suspended t the beginning of the experimentl period. n ll the other cses it ws given throughout the period. n Groups nd 2 there were three cses of multiple denomt (confirmed histologiclly), two of which (Cse V, Group, nd Cse V, Group 2) hd definite negtive clcium blnce, while Cse V, Group 2, ws prcticlly in clcium equilibrium. Group 3. Ptients who hd hd x-ry before the experimentl period (2 cses) Of these, Cses to X hd hd deep x-ry therpy to the thyroid glnd but ech still hd rised metbolism, rnge + 5 to + 56 per cent, t the time of the experimentl period. Cses to V inclusive were in positive clcium blnce nd either in positive phosphorus blnce or pproximtely in phosphorus equilibrium. Cse X ws privte ptient who ws exmined on two occsions; () three months fter dose of 4 r. to the thyroid he ws in slight negtive clcium blnce, nd (b) five months fter the ppliction of rdium collr to the thyroid region he ws in positive clcium blnce. Cse X ws exmined during her first course of x-ry therpy nd ws in negtive clcium blnce. Cses X nd X hd been treted with superficil x-ry; t the time of the experiment they both hd rised bsl metbolism, +26 nd + 53 per cent respectively, both were in very slight positive clcium blnce. The cses of Group 3 were selected for experimentl study becuse they hd remined hyperthyroidic in spite of x-ry therpy. Their fterhistories re shown in the protocol. Three cses

4 546 were subsequently operted on. Cses V nd V hd definite hyperplsi histologiclly. Cse X ws doubtful lymphdenoid goiter. study of Figure 3 will show the totl lck of reltionship between rised metbolism in hyperthyroidism nd mobiliztion of bone slt s evidenced by the stte of the clcium nd phosphorus blnce. Of the twelve cses only one hd negtive clcium blnce, nd this cse ws hving the first course of rdition t the time of the experimentl period. The result of the studies on clcium nd phosphorus blnce on these cses indictes tht thyroxin cnnot be the cuse of the mobiliztion of bone slt in hyperthyroidism. Group 4. Ptients studied before nd fter rdition of the thyroid (4 cses) Cses nd were in definite negtive clcium nd phosphorus blnce before nd definite positive clcium nd phosphorus blnce fter rdition. Cse ws in positive clcium nd phosphorus blnce before but in negtive clcium nd phosphorus blnce fter two courses of deep rdition. This ptient ws subsequently operted on, but within six months of opertion hd nother course of deep rdition becuse of recurrence of the hyperthyroidism. On the evidence of the clinicl condition nd the bsl metbolism, the x-ry seemed to stimulte the whole thyroprthyroid pprtus in this ptient. The fourth cse ws ged 4. She ws in gross negtive clcium nd phosphorus blnce before x-ry nd ws still in definite negtive clcium nd phosphorus blnce fter x-ry, but s only two months hd elpsed since the rdition it ws probbly too erly to get the finl effect of the rys on the prthyroid glnds. Nitrogen blnce in the mteril studied We endevored to hve ech ptient in nitrogen equilibrium but were not lwys successful; this is the most serious objection to using single four-dy period experiment. f such mens of investigtion should become routine, lrger nitrogen intkes re essentil. n our mteril, out of thirty-four periods there ws positive nitrogen blnce or equilibrium (less thn -. grm per dy) in twenty cses nd loss of 2 grms or F. S. HNSMN ND W.. CRR FRSER less dy in eight cses. The gretest loss ws in the 4-yer-old ptient, who lost 5 grms of nitrogen dy. There cn be little doubt tht definite negtive nitrogen blnce disturbs clcium metbolism nd introduces complictions into the interprettion of the results. However, in the present study if we excluded from our dt ll the ptients who hd negtive nitrogen blnce greter thn 2 grms dy-group, Cse ; Group 2, Cse ; Group 3, Cse X (two periods out of five); Group 4, Cses nd V-the generl tenor of the results would in no wise be ffected. DSCUSSON There is in generl negtive clcium nd phosphorus blnce in untreted hyperthyroidism. The negtive clcium blnce, however, is not invrible, nd its extent bers no reltionship to the mount of circulting thyroxin s mesured by the level of the bsl metbolism. The dministrtion of iodine, provided it does not bring the metbolism to norml, hs no pprent influence on the stte of the clcium nd phosphorus blnce. Therpeutic rdition (deep or superficil) to the neck determines in the mjority of cses profound chnge in the clcium nd phosphorus metbolism; two to three months fter irrdition the clcium nd phosphorus blnce tends to become positive irrespective of the level of the bsl metbolism t the time the blnces re estimted. n the series of ptients presented in this pper the clcium nd phosphorus blnces were positive in twelve out of fifteen ptients. The experiments were conducted two or more months fter irrdition nd t the time the bsl metbolism ws definitely rised in ech cse. The most probble explntion of the negtive clcium nd phosphorus blnce in untreted hyperthyroidism nd the shift towrds positive blnce in cses who hve received rdition is tht in hyperthyroidism the prthyroid glnds undergo vrying degrees of hyperplsi nd tht rdition hs more profound effect on hyperplstic prthyroid tissue thn on hyperplstic thyroid tissue. nother possible explntion is tht the thyroid glnd secretes second hormone nd tht the cells responsible for its production re more rdio-sensitive thn the cinr cells tht produce thyroxin. t seems unnecessry to dis-

5 CLCUM ND PHOSPHORUS METBOLSM cuss the possibility of the pituitry glnd being involved. Cope nd Donldson, in recent rticle in this Journl (2), discussed the clcium nd phosphorus metbolism of ptient who hd recurrent hyperthyroidism (postopertive) ssocited with hypoprthyroidism. This ptient ws found to be in clcium nd phosphorus equilibrium t time when the bsl metbolism, s result of the dministrtion of potssium iodide, ws somewht below norml, nd in negtive clcium nd phosphorus blnce when the bsl metbolism rose fter the potssium iodide ws left off. The uthors interpret their findings s follows: "The studies of the clcium nd phosphorus blnce mde on this ptient confirm the findings of ub nd his coworkers. The mrked increse in clcium nd phosphorus excretion to bove norml, occurring during the time of incresed metbolic rte with signs of thyrotoxicosis nd con- 547 tinued tetny, lends substntil support to the belief tht the incresed excretion in hyperthyroidism is not due to concomitnt overctivity of the prthyroid glnds." There is n obvious increse in the clcium nd phosphorus excretion in Cope nd Donldson's ptient when the bsl metbolism ws rised, but there re possibilities to be considered other thn tht this incresed excretion of clcium ws due to mobiliztion of clcium resulting from the " specific effect of the thyroxin circulting in excess " (3). Firstly, the diet being prcticlly the sme s tht given when the bsl metbolism ws low led to n incresed negtive nitrogen blnce, nd consequent lrge mobiliztion of phosphorus to which Cope nd Donldson refer; the incresed cidity of the orgnism thereby determined would ffect clcium metbolism. The degree of tetny ws not the sme on the two occsions; during the experi- BL X +6 t"& 4dt penod s ± *D t -4- r 4 'Pr 4 t " 4!, - Ft 5 9. Co bnce n Shown thus v &MR.. Shewn thus i FG. 5. STTE OF CLCUM BLNCE ND BSL METBOLC RTE (DURNG THE ExPER- MENTL PEROD) ON THE SME ORDNTE 3 OBSERVTONS ON 26 CSES, GROUPS TO 4 NCLUSVE. THE CHLD, GED 4, CSE 4, GROUP 4, EXCLUDED. The cses re chrted in descending order of clcium loss. This grph demonstrtes the bsence of correltion between the stte of the clcium blnce nd the degree of hyperthyroidism s mesured by the bsl metbolic rte.

6 548 F. S. HNSMN ND W.. CRR FRSER mentl period when the bsl metbolism ws low there ws ctive tetny, during the period when the bsl metbolism ws rised the tetny ws prcticlly bsent. The results of the experiments on this ptient re equivocl; they my denote specific effect of the incresed circultion of thyroxin on bone slt, s Cope nd Donldson interpret them, or the results my be simply n expression of the summtion of three other fctors, undernutrition, cidosis, nd incresed ctivity of the prthyroid glnds, ech of which of themselves re conducive to clcium loss. When the results obtined in the present study re considered, the sme mbiguity does not rise. Here we hve rnge of clcium blnces from -3. grms of clcium per four-dy period to grms per four-dy period, with n excess of circulting thyroxin in ech of the thirtyfive experimentl periods. The results of ll the observtions re chrted in Figure 5. Sttisticlly8 there is no correltion between the level of the bsl metbolism nd the stte of the clcium blnce. The evidence is complete tht thyroxin per se hs no effect on clcium ctbolism. The results do not prove tht vrition in prthyroid function is the true explntion of the observed phenomenon, but in the present stte of our knowledge it is the most logicl thesis. Physiologicl requlirements of diets for use in clcium nd phosphorus studies on humn beings t is importnt to consider the physiologicl requirements of diets for use in clcium nd phosphorus studies on humn beings. n experimentl work, stndrd conditions re essentil, but in metbolic studies there must be vribles; if constnt diet is used tht is indequte in vrious wys, the nutrition of different individuls suffers to vrying extent, nd in turn the metbolism of substnces under investigtion my be disturbed. f the components of the diet re kept constnt, but chnge quntittively though proportionlly to meet cloric requirements, vrible is introduced, s the subjects re not exmined on the sme diet. The clcium content of the diet of the present study pproximtes tht of " norml diets," nd is greter thn tht employed by Buer, lbright, 3 See ppendix for sttisticl nlysis of this dt. nd ub (3). ts use demonstrtes tht in hyperthyroidism wide rnge of clcium blnce is possible. The stte of the clcium blnce is independent of the degree of hyperthyroidism or the ctul clcium content of the diet, i.e., the stte of clcium blnce is pprently not directly influenced by the clcium content of the diet. n some ptients in whom the metbolism remined t comprtively constnt elevtion, nd the clcium content of the diet lso remined constnt, the clcium blnce ws observed to pss from gross negtive to definite positive blnce. When hyperthyroidism is ssocited with negtive clcium blnce, there is n pprent inbility to ssimilte the clcium of the food quite prt from the mobiliztion of clcium from the bones, or in other words, there is clcium dirrhe. stndrdized procedure for use in vrious lbortories would be very vluble, s the results of experiments on clcium nd phosphorus blnce must vry when diets re used s divergent in principle s tht of the Boston School nd tht of the present study. SUMMRY ND CONCLUSONS. Untreted hyperthyroidism is generlly but not invribly ssocited with negtive clcium nd phosphorus blnce. 2. There is no reltionship between the level of the bsl metbolism nd the mount of clcium nd phosphorus excretion. 3. The orl dministrtion of Lugol's iodine hs no specific effect on clcium nd phosphorus metbolism. 4. rrdition of the thyroid region, in hyperthyroidism leds to profound chnges in clcium nd phosphorus metbolism. n the mjority of ptients clcium nd phosphorus equilibrium or positive clcium nd phosphorus blnce occurs two months or more fter the irrdition. 5. The chnge in clcium nd phosphorus blnce tht follows irrdition of the thyroid region is independent of the ctivity of the thyroxinproducing mechnism. 6. The most likely explntion of the chnges in clcium nd phosphorus metbolism in hyperthyroidism nd of the effect of irrdition is tht in hyperthyroidism there is n ssocited hyperprthyroidism nd tht the hyperplstic prthyroid glnds re rdio-sensitive.

7 CLCUM ND PHOSPHORUS METBOLSM 549 *.. Cs P?

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11 CLCUM ND PHOSPHORUS METBOLSM 553 i co8 i ' l 25 i!ex} ' to 9-94 es z - - l l _ o~~~~~~~c + Oo Fe gco co $+ +S P i 9 i totoew *e!i! cwe 8,.%" s i c "- 8 s 's + < cm o - ~~ ~ ~ ~~ e4 e4 co - -4 t- C _ e " i s ! _'.4 6: 9 7 :4 - C) Mt C4 cq 9.VD

12 554 F. S. HNSMN ND W.. CRR FRSER STTSTCL NLYSS (By W.. Crr Frser) Correltion between the stte of the clcium blnce nd the bsl metbolic rte of the mteril of the present study The thirty-one experimentl periods cn be divided into two groups ccording to the stte of the clcium blnce: () 4 periods showing positive clcium blnce per four-dy period. (2) 7 periods showing negtive clcium blnce per four-dy period. The correltion between the stte of the clcium blnce nd the bsl metbolic rte of these two groups cn be investigted. Following Fisher's method (Section 34 (4)) significnce cn be ttributed to vlue of correltion coefficient derived from smple when correltion coefficient s lrge s the one found would be obtined t most once in every twenty or more rndom smples of similr size from n infinite popultion which showed zero correltion. Subjects in positive clcium blnce per four-dy period The correltion coefficient between the stte of clcium blnce nd the bsl metbolic rte is correltion coefficient s lrge s this would be obtined in one out of every four rndom smples of the 4 pirs of observtions drwn from n infinite popultion showing zero correltion. On the evidence, therefore, there is zero correltion between the bsl metbolic rte nd the stte of the clcium blnce per four-dy period for subjects in positive clcium blnce. Subjects in negtive clcium blnce per four-dy period The correltion coefficient between the stte of clcium blnce nd the bsl metbolic rte is +.8. correltion coefficient s lrge s this would be obtined in pproximtely one out of every two rndom smples of 7 pirs of observtions drwn from n infinite popultion showing zero correltion. On the evidence, therefore, there is zero correltion between the bsl metbolic rte nd the stte of the clcium blnce per four-dy period for subjects in negtive clcium blnce. Combintion of the two groups Hving shown tht ech group is equivlent to rndom smple drwn from n infinite popultion showing zero correltion between the stte of the clcium blnce per four-dy period nd the bsl metbolic rte, we cn estimte the weighted correltion coefficient of the two smples ccording to the method of Fisher (Section 35, exmple 33 (4) ). This estimte gives -.5 for the correltion between the stte of clcium blnce nd the bsl metbolic rte. correltion coefficient equl to this figure would be obtined in eight out of every ten rndom smples of this size by smpling n infinite popultion of which the correltion is zero. CONCLUSON This investigtion shows tht there is no correltion between the stte of the clcium blnce per four-dy period nd the bsl metbolic rte. BBLOGRPHY. Hnsmn, F. S., nd Wilson, F. H., Clcium nd phosphorus metbolism in diseses of the thyroprthyroid pprtus.. Clcium, phosphorus nd totl metbolism in hyperthyroidism nd the prt plyed by the prthyroid glnds. M. J. ustrli, 934,, Cope, O., nd Donldson, G.., Reltion of thyroid nd prthyroid glnds to clcium nd phosphorus metbolism. Study of cse with coexistent hypoprthyroidism nd hyperthyroidism. J. Clin. nvest., 937, 3, Buer, W., lbright, F., nd ub, J. C., Studies of clcium nd phosphorus metbolism.. The clcium excretion of norml individuls on low clcium diet, lso dt on cse of pregnncy. J. Clin. nvest., 929, 7, Fisher, R.., Sttisticl Methods for Reserch Workers-Oliver nd Boyd, London, 936, 6th ed., revised nd enlrged.