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Cycloserine treatment of out-patients with chronic drug resistant pulmonary tuberculosis
Tubercle, Lond., (1961), 42, 7
CYCLOSERINE DRUG
TREATMENT OF OUT-PATIENTS WITH CHRONIC RESISTANT PULMONARY TUBERCULOSIS J. WALLACE CRAIG and HOWARD WILLIAMS lslington Chest Clinic
J. M. ALSTON Whitthlgton Hospital, London
SUMMARY Twenty-four patients with chronic drug resistant pulmonary tuberculosis were included in a 'double-blind' trial of cycloserine. Sixteen patients were originally in the treatment group receiving cycloserine-isoniazid capsules, but three were removed as the trial progressed. There were eight patients in the control group receiving isoniazid alone at the start of the trial, and two of these were removed later. The trial consisted of one month in-patient and eleven months out-patient treatment, with a follow-up period of six months. The dosage ofcycloserine was 250 mg. twelve hourly and of isoniazid 150 mg. twelve hourly. Ten patients in the cycloserine group showed striking weight gains, seven pronounced clinical improvement and four radiographic improvement, compared with one patient showing such change in the control group. Temporary sputum 'conversion' occurred in only three of the cycloserine group patients. Toxic effects occurred in nine out of 16 cycloserine group patients; the drug was withdrawn in three. Five out of eight patients in the control series also complained of symptoms, the treatment having to be discontinued in two. In a dosage of 250 mg. twelve hourly, cycloserine was used without serious toxic effects, and this dose was considered safe for use in out-patients. In the three patients with detailed sputum sensitivity tests available two developed cultures with cycloserine resistance eight times that of the control strain H37Rv. after twelve months treatment, and this degree of resistance remained throughout the six months follow-up period.
Since the discovery of cycloserine in 1955 many papers on its use have been published. The drug is now available in Great Britain on prescription, but this was not so in March 1958 when a controlled trial was started at lslington Chest Clinic on chronic drug-resistant pulmonary tuberculosis patients. Among the earlier papers that by Epstein, Nair and Boyd (1955-6) influenced us in the mode of our investigations. These authors concluded that cycloserine was effective in patients with chronic pulmonary tuberculosis who had failed to respond to existing drugs, and reported that resistance to cycloserine did not develop either clinically or in vitro. Studies hi vitro by Cummings, Patnode and Huggins (1955) suggested a slight degree of synergism between cycloserine and isoniazid; and Epstein, Nair and Boyd (1957) treated a group of patients with reduced doses of both cycloserine and isoniazid. The results showed a degree of effectiveness against pulmonary tuberculosis thought to be superior to that seen when either drug is used alone. Early papers by Lillick and others (1955-6) on the treatment of respiratory tract infections, and by Herrold, Boand
8
TUBERCLE
and Kamp (1955-6) on the treatment of urinary tract infections showed that cycloserine was also effective against a wide range of gram-positive and gram-negative organisms. The toxic effects of cycloserine have been well documented. At the Veterans Administration Conference in 1956 on the chemotherapy of tuberculosis, one series was reported in which toxic effects occured in 17 of 76 patients receiving 1-1.5 g. ofcycloserine daily, and in only I of 22 receiving 0.5 g. daily (Epstein, Nair and Boyd, 1956). According to Modave (1957) the frequency of neuropsychic disturbance depends on the size of the daily dose. He stated that on a dose of less than 1 g. a day these disturbances are comparatively rare or benign and disappear spontaneously despite continued treatment. More serious incidents may be feared when the plasma concentration passes a certain threshold (around 30 ,~g./ml). A more recent paper by Holmes, Martin and Fetterhoff (1959) showed that if the serum level could be maintained between 20 and 40 ~g./ml. there was a therapeutic response without any evidence of drug toxicity, supporting Modave's views. Despite neurological side effects Epstein. Nair and Boyd reported no blood or urinary changes. In eight patients studied in detail, liver and kidney function tests remained normal throughout and there were no E.C.G. changes. Renzetti and others (1956) in a trial of the drug on seven patients discovered no abnormalities in red or white cell counts, or in complete urinalysis and liver function tests ca'tried out monthly. These factors were taken into consideration in planning our trial.
Methods The trial involved only twenty-four patients, twenty-one men and three women, and took the form of a 'double-blind' investigation. All the patients had chronic bilateral cavitated disease and were considered unsuitable for thoracic surgery. During the previous two years they had produced sputum persistently containing living tubercle bacilli, which were resistant to isoniazid and to either streptomycin or PAS on at least two occasions before the commencement of the trial. The patients were divided into two groups by random allocation, namely a control group and a treatment group. No one concerned in the trial, with the exception of the clinic head clerk and the biochemist, knew into which group patients had been placed. Both groups were given capsules identical in external appearance. They were supplied by the manufacturers according to our specifications. The control group capsules contained 75 mg. of isoniazid with purified talc, while the treatment group capsules contained 125 mg. of cycloserine in addition to 75 mg. of isoniazid. Both groups took two capsules at 8 a.m. and two at 8 p.m. also 50 mg. of pyridoxine with each dose. The trial lasted one year, with a follow-up period of six months. The patients spent the first month of the trial as in-patients, and the remaining period as out-patients. Monthly sputum tests were carried out up to the sixth month and thereafter at two-monthly intervals. The sputum was examined on smear and culture for acid-fast bacilli and sputum sensitivity tests were set up. The cultures were made by charging two cotton-wool swabs with sputum and treating the swabs for 35 minutes with 5 per cent oxalic acid, and, for 10 minutes with 5 per cent sodium citrate, then inoculating a slope of L6wenstein-Jensen medium with them (Nassau, 1958). The sensitivity tests were made by inoculating tubes of the same medium to which drugs were added as f o l l o w s : Streptomycin 3,10,30, ~g./ml. PAS . . . . . . 2,10,100 p.g./ml. Isoniazid . . . . 0.2,1,5,10,50 ~.g./ml. Cycloserine . . . . 20,40,80,160 ~g./ml. The results were read after 4 weeks incubation at 37 ~ C. The sputum was also examined for other organisms. Sputum volume measurements in mls. were made at each visit. A monthly chest radiograph was taken during the first six months and at two-monthly intervals
CYCLOSERINF
TREATMENT
IN DP, UG
RESISTANT
TUBERCULOSIS
until the end of the follow-up period. The radiographs were judged independently by three chest physicians. At the same time intervals the ESR (Westergren), haemoglobin and total and differential white cell counts were recorded. Monthly serum cycloserine levels were requested for the first six months and thereafter at two-monthly intervals until the end of the trial. The blood was taken four hours after the morning dose. These results were not made known until the end of the trial; but if, because of symptoms, it was considered necessary to discontinue treatment, results were requested. This happened in two cases only when it had already been decided to discontinue treatment; in both cases the patients were found to be in the group not receiving cycloserine and were withdrawn from the trial. Results were also disclosed if exceeding 30 [zg./ml. This happened in one case only, and treatment was continued. The patients were weighed at every visit; and a mid-stream specimen of urine was taken and examined for protein, glucose and ketones. Results
Because the patients were in the trial for one year, and had extensive disease with cultures resistant to isoniazid and to either streptomycin or PAS it was felt on ethical grounds that more patients should be included in the cycloserine-isoniazid group than in the control. Dr. lan Sutherland of the Medical Research Council's Statistical Research Unit was consulted on this point and he agreed that a moderate disparity in numbers was permissible; we are indebted to him for arranging that the allocations should be made at random, approximately in the proportion of three cycloserineisoniazid allocations to two isoniazid allocations. These were not known until the end of the trial. Then it was revealed that there were sixteen cycloserine and eight control group patients at the start of the trial. Three treatment group patients were removed from the trial after two days, two months and ten months, respectively, because of symptoms. Two control group patients were removed after two months also because of symptoms. There remained 19 patients, 13 in the cycloserine group and 6 in the control group. Clinical C h a i g e The results are given in Table 1, and are based on improvement or deterioration of the patients' general condition as assessed by the examining doctor and on the patients' symptoms. Weight Change Ten of the patients in the cycloserine-isoniazid group and one of the control group, made striking weight gains ranging from 9 to 19 ibs. which were maintained over the period of the trial. Both groups showed similar average weight gain during the first month of in-patient treatment. Thereafter the two groups differed, the cycloserine-isoniazid group continuing to gain until an average weight rise of approximately nine pounds was recorded. Only at the end of the trial did it start to decline. TABLE [,--CHANGES IN CLINICAL CONDITION
Drug
Cycloserine Group Control Group
Total CommenchL~ Trial 16 _8 ......
Removed fi'om Trial
Remahthsg
Change hi Clhficul Condition
3*
13
bnproved
Unchanged
7
5
l
3
2
_2~ . . . . . . . . 6 . . . . . . . . I. . . . . .
Worse
....... 7. . . . * O n e p a l i e n t r e m o v e d a f t e r t w o d a y s , o n e a f t e r t w o months and one after ten months. + Both removed after two months.
10
TUBERCLE TABLE ][I.--AVERAGE WEIGHT GAIN OR
Loss DURING
TREATMENT,
A verage weight change compared with pre-treatment weight (Ibs.) i. In-Patient[ Out-Patient Follow-Up Group I month 3 months 6 months 8 months 12 months 18 months
Cycloserine
-t-4"3
Control
+4
I
.1.8'4
.1.9
.1.9"1
-t-9
"
.1.1.2"5
+2
.1.2-2
-- I
i
-- 1
On the other hand the control group showed an average weight loss more marked as the trial progressed, becoming a deficit of one p o u n d at twelve months. (see Table II).
Sputum Voiurne N o important fall o f sputu:~
: :Be was noted in either group.
Bacteriological Changes In the isoniazid group one patient had negative sputum t h r o u g h o u t the trial, the remainder produced sputum cultures frequently positive. Three or more m o n t h s consecutive absence o f tubercle bacilli on smear and on culture was obtained in three out o f the thirteen cycloserine-isoniazid patients; all three later had further positive cultures. N o n e were negative on culture on completion o f the trial. Table ]II shows changes in sputum culture results in both groups during treatment. Cycloserh~e Resistance of Organisms : - - T h r o u g h o u t the trial and follow-up period bacilli from only three patients out o f thirteen in the cycloserine-isoniazid group were consistently tested for cycloserine resistance. In one patient sensitivity remained constant at approximately twice that o f the control strain H37Rv (resistance o f 2). In the other two the sensitivity decreased from being equal to that o f the control at the start o f the trial, to eight times more resistant at the end o f the trial. This degree of resistance was maintained during the follow-up period. In similar tests made with a group o f our patients outside the trial, at the time o f starting cycloserine treatment the cultures o f 13 out o f 27 patients showed sensitivity equal to the control; 12 showed resistance ratios o f 2. O f the remaining two patients one had a resistance ratio o f four, a n d the other eight. It appears therefore that the year's treatment with cycloserine may increase the resistance o f cultures from some patients to eight times that o f the H37Rv. strain. Other Organisms:--Cycloserine had no apparent effect on other organisms in the sputum. It was noted that the same types tended to recur in the same individual irrespective o f group.
Radiographic Change Four patients in the cycloserine-isoniazid group showed reduction o f cavity size and less mottling, seven no change, and two showed deterioration. In the isoniazid group one patient improved radiographically, three showed no change and two were worse.
Blood Changes The sedimentation rate showed no important change in either group. No abnormalities were noted in the blood films, or total and differential white cell counts. TABLE [[I.--CHANGES IN CULTURE RESULTS DURING TREATMENF
Group
Cycloserine
Control
Tolal ill Trial 13
6
No. With a Positive Culture i Before Months o f Treatment Trial 4 6 8 10 12 i 2 13
5*
, 6
6
5
6
8
6
: 4
4
3
5
5
4
* One patient had negative cultures throughout treatment.
C Y C L O S E R I N E TREATMENT IN DRUG-RESISTANT TUBERCULOSIS
II
TAaLE IV.--Tox~c EFFECTS
Serum Cycloserine Levels (Ltg/ml )
I
Group
Pt.
Urine Examination
Blood Urea (mg./lO0 ml.)
22
Albumentrace; sugar+
not done
16 9 at death
27
Albumen + + +.
145, 300 at death.
Symptoms
Month of i complaint CycIoserine +isoniazid
I*
Giddiness, transient loss of memory Drowsiness
2*
lsoniazid alone.
~ i : i
20
Highest !
3*
Giddiness, depressed,
24
30
Albumentrace.
17
4
I1
18
Sugar-trace.
22
5 6 7
Giddiness, emotionally labile. Giddiness. Drowsiness One blackout !
17 21
27 30 26
----
20 not done 26
8 9
Drowsiness. 2 blackouts.
13 17
23 23
---
30 30
I*
Drowsiness.
2*
15
--
Headaches.
--
--
--
--
Albumen + + --. --
5
.
. --
Unreliable witness. Unreliable witness. Amyloid.
not done
Chronic neurosis.
--
not done not done
Sugar-trace.
not done
.
Diabetes, chronic anxiety state. Uraemia, . anayloid, died 11 days. streptomycin giddiness before. Alcoholic.
35
i
Headache. Gastro . ! intestinal. ! Giddiness.
Comment
--
9 Removed from the trial.
Serum Cycloserine Levels O n o n e o c c a s i o n the s e r u m c y c l o s e r i n e level rose a b o v e 30 ~.g./ml. to 52 ~g./ml., o t h e r w i s e all v a l u e s o b t a i n e d w e r e b e l o w this. T h e l o w e s t r e c o r d e d s e r u m c y c l o s e r i n e level w a s 9 ~g./ml, a n d the m o n t h l y a v e r a g e v a r i e d b e t w e e n 18 a n d 26 p.g./ml.
Toxic Effects T h e s e are s h o w n in T a b l e IV, a n d for t h i s p u r p o s e all 24 p a t i e n t s a r e i n c l u d e d . N i n e o u t o f s i x t e e n in the c y c l o s e r i n e - i s o n i a z i d g r o u p c o m p l a i n e d o f s y m p t o m s , a n d five o u t o f e i g h t o f the c o n t r o l g r o u p . F o u r p a t i e n t s in the c y c l o s e r i n e - i s o n i a z i d g r o u p c o m p l a i n e d o f g i d d i n e s s , t h r e e o f d r o w s i n e s s , t h r e e h a d p s y c h o l o g i c a l d i s t u r b a n c e s a n d t w o h a d ' b l a c k o u t s ' . O f the t h r e e w h o h a d m e n t a l s y m p t o m s , o n e b e c a m e m i l d l y d e p r e s s e d , the s e c o n d m o r e e m o t i o n a l , w h i l e the t h i r d c o m p l a i n e d o f a s e n s e o f u n r e a l i t y a n d b e c a m e m o r e forgetful. T h e last p a t i e n t w a s an u n s t a b l e d i a b e t i c w i t h a c h r o n i c a n x i e t y state. B e c a u s e o f t h i s his t r e a t m e n t w a s d i s c o n t i n u e d a f t e r t w o months. T h e d r u g w a s a l s o d i s c o n t i n u e d in t w o o t h e r c y c l o s e r i n e g r o u p p a t i e n t s , o n e a f t e r t w o d a y s b e c a u s e o f d r o w s i n e s s a n d the o t h e r a f t e r ten m o n t h s b e c a u s e o f p e r s i s t e n t b u t m i l d g i d d i n e s s . In the c a s e o f t h e f o r m e r p a t i e n t , w h e n the d r u g w a s s t o p p e d a f t e r t w o d a y s the s e r u m c y c l o s e r i n e level w a s 16 ~.g./ml. T w o d a y s l a t e r it w a s 27 ~g./ml., the b l o o d u r e a w a s 145 m g . / 1 0 0 ml., a n d the u r i n e w a s l o a d e d w i t h a l b u m e n . T h e p a t i e n t d i e d a f t e r eleven days. J u s t b e f o r e d e a t h the b l o o d 6 r e a w a s 300 m g . / 1 0 0 ml. a n d t h e r e w a s still a seru.m c y c l o s e r i n e level o f 9 ixg./ml. A m y l o i d d i s e a s e w a s
12
TUBERCLE
confirmed at post mortem. The two cycloserine group patients who complained of 'blackouts' were both unreliable witnesses. Neither was seen during an attack, which in both patients lasted a few seconds. Loss of consciousness was not corroborated, nor was there a history of injury or of incontinence. Of the patients who complained in the control group, two were so persistent in their complaints that it was necessary to remove them from the trial after two months.
Discussion The number of. patients in t h i s t r i a l was inevitably small as only twenty four fulfilled all the conditions necessary for inclusion and were prepared to co-operate for the period involved. Nevertheless, as the trial was a controlled one, it was felt that some of our results might be of value. In planning the trial, it was considered that as all the patients had cultures resistant to isoniazid, any therapeutic affect attributable to that drug would be negligible, and any difference noted between the two groups would be due to the cycloserine. The pyridoxine was given to lessen any possible side-effects which might be induced by the isoniazid. Some American workers have used pyridoxine in an attempt to reduce toxic effects due to cycloserine (Raleigh, 1959). One of the notable features in many reports on the clinical effect of cycloserine has been gain in weight (Grove-White and Supramaniam, 1958; Ritchie and others, 1958; Leites, 1959). Our results support the findings of these and other authors. Four patients in the cycloserine-isoniazid group, compared with one of the control gronp showed radiographic improvement. This improvement was unexpected because of the chronic nature of the disease. Leites reported 23 per cent of radiographic improvement in her patients under conditionrs very similar to ours. Leites also reported a 'reversal of infectiousness' in 21 per cent who had failed to respond to pro}onged treatment with other drugs. In our trial three out of thirteen underwent temporary 'sputum conversion', in the cycloserine group, while one patient in the control group had negative sputum throughout. These results point to a mild therapeutic response to cycloserine in chronic drug resistant pulmonary tuberculosis patients. Weinberger, Lindars, and Pasha (1958) expressed concern that tl~e therapeutically effective dose of cycloserine might be too close to the toxic dose for the drug to be used universally. On a dosage of 250 rag. twelve hourly only infrequent toxic effects were encountered in our trial and no serious neurotoxic effects occurred. With the exception of the three patients already described, the drug was continued for twelve months. As five patients complained of symptoms with serum cycloserine levels below 20 ~g./ml. the significance of the symptoms is questionable, particularly as five out of eight control group patients also complained of symptoms. Two of the latter complained with such persistance as to cause them to be withdrawn from the trial, yet both had taken isoniazid previously without ill-effect. Provided renal function was not impaired, as in one of our patients with amyloid disease, 250 rag. cycloserine twelve hourly proxcd a safe dose to give out-patients from the point of view of drug toxicity. On this dosage deterv ;ons of serum cycloserine levels are unnecessary, unless the patient complains of symptoms. It is now generally accepted that bacillary resistance to cycloscrine therapy develops slowly. Epstein and others (1958) in a trial of cycloserine-isoniazid on eighty-one newly diagnosed patients with pulmonary tuberculosis used the same dosage combination as in our trial. They concluded that from 0.5 g. of cycloserine a day there was no evidence of decreased bacillary sensitivity. As far as conclusions may be drawn from our results, cultures from two out of three of our patients with detailed sensitivity tests available showed a resistance eight times that of the control at twelve months, a degree of resistance which was maintained during the follow-up period. Our limited evidence would suggest that cycloserine should not be given on its own. Epstein and others (1958)
CYCLOSERINE TREATMENT IN DP, UG RESISTANT TUBERCULOSIS
13
s t a t e t h a t c y c l o s e r i n e a n d i s o n i a z i d w o r k s y n e r g i s t i c a l l y a n d in t h e i r series t w e n t y - n i n e o u t o f t h i r t y - f i v e p a t i e n t s w e r e p r o d u c i n g s p u t u m n e g a t i v e a t six m o n t h s . A s a l u t a r y c o n c l u s i o n o f the p a p e r , h o w e v e r , w a s the a u t h o r s ' s t a t e m e n t t h a t r e s i s t a n c e to i s o n i a z i d d e v e l o p e d at the s a m e rate a s t h a t seen w h e n i s o n i a z i d is g i v e n alone. w e wish to express our thanks to Dr. G. P. Maher Loughnan for his advice and help in drawing up our original protocol. Dr. Joanna Ward gave great assistance in collecting and analysing the results. Mrs. Halls, the clinic head clerk, controlled the allocation of treatment and the clinic staff rendered valuable assistance. M iss M. F. Crowley, B.Sc., was in charge of all biochemical investigations. We express our appreciation to her and to Mr. R. Amon and Miss E. Hutchinson for, technical bacteriological help. Finally we are grateful to Mr. E. A. G. Cook of Messrs. Eli Lilly & Co. Ltd. who provided us with all the capsules for this trial. REFERENCES CUMMINGS, M. M., PATNODE, R. A., & HUGGINS, P. C. (1955) Antibiot. & CIwmother., 5, 198. EPSTEIN, I. G., NAIR, K. G. S., & BOYD, L. J. (1955-56). Antibiot. Amt., 141. EeSTEIN, I. G., NAIR, K. G. S., & BOY~, L. J. (1956). Transactions of the 15th Conference on the CI]emotheraphy of Tuberculosis, p. 365, Veterans Administration, Washington. ErSTEIN, I. G., NATR, K. G. S., & BOYD, L. J. (1957). Amer. Rev. Tuberc., 75, 553. EPSTEIN, I. G., NAm, K. G. S., BOYD, L. J., & AUSlnTZ, P. (1958). Dis. Chest, 33, 371. GROVE-WHITE, R. J., & SUPRAMANIAM,J. M. J. (1958). Tubercle, Lond., 39, 213. HERROLO, R. D., BOAND, A. V., & KAMP, M. (1955-56). Antibiot. Ann., 655. HOLMES, C. X., MARTIN, G. E., & FETTERHOFF, K. I. (1959). Dis. Chest, 36, 591. LEITES, V. (1959). Amer. Rev. resp. Dis., 80, 89. LJLLICK, L., STRANG, R., BOYD, L. J., SCraWqMMER, M., & MULINOS, M. G. (1955-56). Antibiot. Amt.. 15~. MODAVE, J. (1957). Antibiot. Med., 4, 535. NASSAU, E. (1958). Tubercle, Lond., 39, J8. RALEtGH, J. W. (1959). Antibiot. Med., 6, 242. RENZETrl, A. D., WRIGHT, K. W., EDL~NG,J. H., & BONN, P. (1956). Amer. Rev. Tuberc., 74, 128. RtTCHIE, J. A., CAMPBELL,A. E. R., CUTHBERT, J., & BRUCE, L. G. (1958). Tubercle, Lond., 39, 289. WEINBERGER, M., LINDARS, D. C., & PASHA, M. A. (1958). Tubercle, Lond., 39, 96.
CYCLOSERINE DRUG
TREATMENT OF OUT-PATIENTS WITH CHRONIC RESISTANT PULMONARY TUBERCULOSIS J. WALLACE CRAIG and HOWARD WILLIAMS lslington Chest Clinic
J. M. ALSTON Whitthlgton Hospital, London
SUMMARY Twenty-four patients with chronic drug resistant pulmonary tuberculosis were included in a 'double-blind' trial of cycloserine. Sixteen patients were originally in the treatment group receiving cycloserine-isoniazid capsules, but three were removed as the trial progressed. There were eight patients in the control group receiving isoniazid alone at the start of the trial, and two of these were removed later. The trial consisted of one month in-patient and eleven months out-patient treatment, with a follow-up period of six months. The dosage ofcycloserine was 250 mg. twelve hourly and of isoniazid 150 mg. twelve hourly. Ten patients in the cycloserine group showed striking weight gains, seven pronounced clinical improvement and four radiographic improvement, compared with one patient showing such change in the control group. Temporary sputum 'conversion' occurred in only three of the cycloserine group patients. Toxic effects occurred in nine out of 16 cycloserine group patients; the drug was withdrawn in three. Five out of eight patients in the control series also complained of symptoms, the treatment having to be discontinued in two. In a dosage of 250 mg. twelve hourly, cycloserine was used without serious toxic effects, and this dose was considered safe for use in out-patients. In the three patients with detailed sputum sensitivity tests available two developed cultures with cycloserine resistance eight times that of the control strain H37Rv. after twelve months treatment, and this degree of resistance remained throughout the six months follow-up period.
Since the discovery of cycloserine in 1955 many papers on its use have been published. The drug is now available in Great Britain on prescription, but this was not so in March 1958 when a controlled trial was started at lslington Chest Clinic on chronic drug-resistant pulmonary tuberculosis patients. Among the earlier papers that by Epstein, Nair and Boyd (1955-6) influenced us in the mode of our investigations. These authors concluded that cycloserine was effective in patients with chronic pulmonary tuberculosis who had failed to respond to existing drugs, and reported that resistance to cycloserine did not develop either clinically or in vitro. Studies hi vitro by Cummings, Patnode and Huggins (1955) suggested a slight degree of synergism between cycloserine and isoniazid; and Epstein, Nair and Boyd (1957) treated a group of patients with reduced doses of both cycloserine and isoniazid. The results showed a degree of effectiveness against pulmonary tuberculosis thought to be superior to that seen when either drug is used alone. Early papers by Lillick and others (1955-6) on the treatment of respiratory tract infections, and by Herrold, Boand
8
TUBERCLE
and Kamp (1955-6) on the treatment of urinary tract infections showed that cycloserine was also effective against a wide range of gram-positive and gram-negative organisms. The toxic effects of cycloserine have been well documented. At the Veterans Administration Conference in 1956 on the chemotherapy of tuberculosis, one series was reported in which toxic effects occured in 17 of 76 patients receiving 1-1.5 g. ofcycloserine daily, and in only I of 22 receiving 0.5 g. daily (Epstein, Nair and Boyd, 1956). According to Modave (1957) the frequency of neuropsychic disturbance depends on the size of the daily dose. He stated that on a dose of less than 1 g. a day these disturbances are comparatively rare or benign and disappear spontaneously despite continued treatment. More serious incidents may be feared when the plasma concentration passes a certain threshold (around 30 ,~g./ml). A more recent paper by Holmes, Martin and Fetterhoff (1959) showed that if the serum level could be maintained between 20 and 40 ~g./ml. there was a therapeutic response without any evidence of drug toxicity, supporting Modave's views. Despite neurological side effects Epstein. Nair and Boyd reported no blood or urinary changes. In eight patients studied in detail, liver and kidney function tests remained normal throughout and there were no E.C.G. changes. Renzetti and others (1956) in a trial of the drug on seven patients discovered no abnormalities in red or white cell counts, or in complete urinalysis and liver function tests ca'tried out monthly. These factors were taken into consideration in planning our trial.
Methods The trial involved only twenty-four patients, twenty-one men and three women, and took the form of a 'double-blind' investigation. All the patients had chronic bilateral cavitated disease and were considered unsuitable for thoracic surgery. During the previous two years they had produced sputum persistently containing living tubercle bacilli, which were resistant to isoniazid and to either streptomycin or PAS on at least two occasions before the commencement of the trial. The patients were divided into two groups by random allocation, namely a control group and a treatment group. No one concerned in the trial, with the exception of the clinic head clerk and the biochemist, knew into which group patients had been placed. Both groups were given capsules identical in external appearance. They were supplied by the manufacturers according to our specifications. The control group capsules contained 75 mg. of isoniazid with purified talc, while the treatment group capsules contained 125 mg. of cycloserine in addition to 75 mg. of isoniazid. Both groups took two capsules at 8 a.m. and two at 8 p.m. also 50 mg. of pyridoxine with each dose. The trial lasted one year, with a follow-up period of six months. The patients spent the first month of the trial as in-patients, and the remaining period as out-patients. Monthly sputum tests were carried out up to the sixth month and thereafter at two-monthly intervals. The sputum was examined on smear and culture for acid-fast bacilli and sputum sensitivity tests were set up. The cultures were made by charging two cotton-wool swabs with sputum and treating the swabs for 35 minutes with 5 per cent oxalic acid, and, for 10 minutes with 5 per cent sodium citrate, then inoculating a slope of L6wenstein-Jensen medium with them (Nassau, 1958). The sensitivity tests were made by inoculating tubes of the same medium to which drugs were added as f o l l o w s : Streptomycin 3,10,30, ~g./ml. PAS . . . . . . 2,10,100 p.g./ml. Isoniazid . . . . 0.2,1,5,10,50 ~.g./ml. Cycloserine . . . . 20,40,80,160 ~g./ml. The results were read after 4 weeks incubation at 37 ~ C. The sputum was also examined for other organisms. Sputum volume measurements in mls. were made at each visit. A monthly chest radiograph was taken during the first six months and at two-monthly intervals
CYCLOSERINF
TREATMENT
IN DP, UG
RESISTANT
TUBERCULOSIS
until the end of the follow-up period. The radiographs were judged independently by three chest physicians. At the same time intervals the ESR (Westergren), haemoglobin and total and differential white cell counts were recorded. Monthly serum cycloserine levels were requested for the first six months and thereafter at two-monthly intervals until the end of the trial. The blood was taken four hours after the morning dose. These results were not made known until the end of the trial; but if, because of symptoms, it was considered necessary to discontinue treatment, results were requested. This happened in two cases only when it had already been decided to discontinue treatment; in both cases the patients were found to be in the group not receiving cycloserine and were withdrawn from the trial. Results were also disclosed if exceeding 30 [zg./ml. This happened in one case only, and treatment was continued. The patients were weighed at every visit; and a mid-stream specimen of urine was taken and examined for protein, glucose and ketones. Results
Because the patients were in the trial for one year, and had extensive disease with cultures resistant to isoniazid and to either streptomycin or PAS it was felt on ethical grounds that more patients should be included in the cycloserine-isoniazid group than in the control. Dr. lan Sutherland of the Medical Research Council's Statistical Research Unit was consulted on this point and he agreed that a moderate disparity in numbers was permissible; we are indebted to him for arranging that the allocations should be made at random, approximately in the proportion of three cycloserineisoniazid allocations to two isoniazid allocations. These were not known until the end of the trial. Then it was revealed that there were sixteen cycloserine and eight control group patients at the start of the trial. Three treatment group patients were removed from the trial after two days, two months and ten months, respectively, because of symptoms. Two control group patients were removed after two months also because of symptoms. There remained 19 patients, 13 in the cycloserine group and 6 in the control group. Clinical C h a i g e The results are given in Table 1, and are based on improvement or deterioration of the patients' general condition as assessed by the examining doctor and on the patients' symptoms. Weight Change Ten of the patients in the cycloserine-isoniazid group and one of the control group, made striking weight gains ranging from 9 to 19 ibs. which were maintained over the period of the trial. Both groups showed similar average weight gain during the first month of in-patient treatment. Thereafter the two groups differed, the cycloserine-isoniazid group continuing to gain until an average weight rise of approximately nine pounds was recorded. Only at the end of the trial did it start to decline. TABLE [,--CHANGES IN CLINICAL CONDITION
Drug
Cycloserine Group Control Group
Total CommenchL~ Trial 16 _8 ......
Removed fi'om Trial
Remahthsg
Change hi Clhficul Condition
3*
13
bnproved
Unchanged
7
5
l
3
2
_2~ . . . . . . . . 6 . . . . . . . . I. . . . . .
Worse
....... 7. . . . * O n e p a l i e n t r e m o v e d a f t e r t w o d a y s , o n e a f t e r t w o months and one after ten months. + Both removed after two months.
10
TUBERCLE TABLE ][I.--AVERAGE WEIGHT GAIN OR
Loss DURING
TREATMENT,
A verage weight change compared with pre-treatment weight (Ibs.) i. In-Patient[ Out-Patient Follow-Up Group I month 3 months 6 months 8 months 12 months 18 months
Cycloserine
-t-4"3
Control
+4
I
.1.8'4
.1.9
.1.9"1
-t-9
"
.1.1.2"5
+2
.1.2-2
-- I
i
-- 1
On the other hand the control group showed an average weight loss more marked as the trial progressed, becoming a deficit of one p o u n d at twelve months. (see Table II).
Sputum Voiurne N o important fall o f sputu:~
: :Be was noted in either group.
Bacteriological Changes In the isoniazid group one patient had negative sputum t h r o u g h o u t the trial, the remainder produced sputum cultures frequently positive. Three or more m o n t h s consecutive absence o f tubercle bacilli on smear and on culture was obtained in three out o f the thirteen cycloserine-isoniazid patients; all three later had further positive cultures. N o n e were negative on culture on completion o f the trial. Table ]II shows changes in sputum culture results in both groups during treatment. Cycloserh~e Resistance of Organisms : - - T h r o u g h o u t the trial and follow-up period bacilli from only three patients out o f thirteen in the cycloserine-isoniazid group were consistently tested for cycloserine resistance. In one patient sensitivity remained constant at approximately twice that o f the control strain H37Rv (resistance o f 2). In the other two the sensitivity decreased from being equal to that o f the control at the start o f the trial, to eight times more resistant at the end o f the trial. This degree of resistance was maintained during the follow-up period. In similar tests made with a group o f our patients outside the trial, at the time o f starting cycloserine treatment the cultures o f 13 out o f 27 patients showed sensitivity equal to the control; 12 showed resistance ratios o f 2. O f the remaining two patients one had a resistance ratio o f four, a n d the other eight. It appears therefore that the year's treatment with cycloserine may increase the resistance o f cultures from some patients to eight times that o f the H37Rv. strain. Other Organisms:--Cycloserine had no apparent effect on other organisms in the sputum. It was noted that the same types tended to recur in the same individual irrespective o f group.
Radiographic Change Four patients in the cycloserine-isoniazid group showed reduction o f cavity size and less mottling, seven no change, and two showed deterioration. In the isoniazid group one patient improved radiographically, three showed no change and two were worse.
Blood Changes The sedimentation rate showed no important change in either group. No abnormalities were noted in the blood films, or total and differential white cell counts. TABLE [[I.--CHANGES IN CULTURE RESULTS DURING TREATMENF
Group
Cycloserine
Control
Tolal ill Trial 13
6
No. With a Positive Culture i Before Months o f Treatment Trial 4 6 8 10 12 i 2 13
5*
, 6
6
5
6
8
6
: 4
4
3
5
5
4
* One patient had negative cultures throughout treatment.
C Y C L O S E R I N E TREATMENT IN DRUG-RESISTANT TUBERCULOSIS
II
TAaLE IV.--Tox~c EFFECTS
Serum Cycloserine Levels (Ltg/ml )
I
Group
Pt.
Urine Examination
Blood Urea (mg./lO0 ml.)
22
Albumentrace; sugar+
not done
16 9 at death
27
Albumen + + +.
145, 300 at death.
Symptoms
Month of i complaint CycIoserine +isoniazid
I*
Giddiness, transient loss of memory Drowsiness
2*
lsoniazid alone.
~ i : i
20
Highest !
3*
Giddiness, depressed,
24
30
Albumentrace.
17
4
I1
18
Sugar-trace.
22
5 6 7
Giddiness, emotionally labile. Giddiness. Drowsiness One blackout !
17 21
27 30 26
----
20 not done 26
8 9
Drowsiness. 2 blackouts.
13 17
23 23
---
30 30
I*
Drowsiness.
2*
15
--
Headaches.
--
--
--
--
Albumen + + --. --
5
.
. --
Unreliable witness. Unreliable witness. Amyloid.
not done
Chronic neurosis.
--
not done not done
Sugar-trace.
not done
.
Diabetes, chronic anxiety state. Uraemia, . anayloid, died 11 days. streptomycin giddiness before. Alcoholic.
35
i
Headache. Gastro . ! intestinal. ! Giddiness.
Comment
--
9 Removed from the trial.
Serum Cycloserine Levels O n o n e o c c a s i o n the s e r u m c y c l o s e r i n e level rose a b o v e 30 ~.g./ml. to 52 ~g./ml., o t h e r w i s e all v a l u e s o b t a i n e d w e r e b e l o w this. T h e l o w e s t r e c o r d e d s e r u m c y c l o s e r i n e level w a s 9 ~g./ml, a n d the m o n t h l y a v e r a g e v a r i e d b e t w e e n 18 a n d 26 p.g./ml.
Toxic Effects T h e s e are s h o w n in T a b l e IV, a n d for t h i s p u r p o s e all 24 p a t i e n t s a r e i n c l u d e d . N i n e o u t o f s i x t e e n in the c y c l o s e r i n e - i s o n i a z i d g r o u p c o m p l a i n e d o f s y m p t o m s , a n d five o u t o f e i g h t o f the c o n t r o l g r o u p . F o u r p a t i e n t s in the c y c l o s e r i n e - i s o n i a z i d g r o u p c o m p l a i n e d o f g i d d i n e s s , t h r e e o f d r o w s i n e s s , t h r e e h a d p s y c h o l o g i c a l d i s t u r b a n c e s a n d t w o h a d ' b l a c k o u t s ' . O f the t h r e e w h o h a d m e n t a l s y m p t o m s , o n e b e c a m e m i l d l y d e p r e s s e d , the s e c o n d m o r e e m o t i o n a l , w h i l e the t h i r d c o m p l a i n e d o f a s e n s e o f u n r e a l i t y a n d b e c a m e m o r e forgetful. T h e last p a t i e n t w a s an u n s t a b l e d i a b e t i c w i t h a c h r o n i c a n x i e t y state. B e c a u s e o f t h i s his t r e a t m e n t w a s d i s c o n t i n u e d a f t e r t w o months. T h e d r u g w a s a l s o d i s c o n t i n u e d in t w o o t h e r c y c l o s e r i n e g r o u p p a t i e n t s , o n e a f t e r t w o d a y s b e c a u s e o f d r o w s i n e s s a n d the o t h e r a f t e r ten m o n t h s b e c a u s e o f p e r s i s t e n t b u t m i l d g i d d i n e s s . In the c a s e o f t h e f o r m e r p a t i e n t , w h e n the d r u g w a s s t o p p e d a f t e r t w o d a y s the s e r u m c y c l o s e r i n e level w a s 16 ~.g./ml. T w o d a y s l a t e r it w a s 27 ~g./ml., the b l o o d u r e a w a s 145 m g . / 1 0 0 ml., a n d the u r i n e w a s l o a d e d w i t h a l b u m e n . T h e p a t i e n t d i e d a f t e r eleven days. J u s t b e f o r e d e a t h the b l o o d 6 r e a w a s 300 m g . / 1 0 0 ml. a n d t h e r e w a s still a seru.m c y c l o s e r i n e level o f 9 ixg./ml. A m y l o i d d i s e a s e w a s
12
TUBERCLE
confirmed at post mortem. The two cycloserine group patients who complained of 'blackouts' were both unreliable witnesses. Neither was seen during an attack, which in both patients lasted a few seconds. Loss of consciousness was not corroborated, nor was there a history of injury or of incontinence. Of the patients who complained in the control group, two were so persistent in their complaints that it was necessary to remove them from the trial after two months.
Discussion The number of. patients in t h i s t r i a l was inevitably small as only twenty four fulfilled all the conditions necessary for inclusion and were prepared to co-operate for the period involved. Nevertheless, as the trial was a controlled one, it was felt that some of our results might be of value. In planning the trial, it was considered that as all the patients had cultures resistant to isoniazid, any therapeutic affect attributable to that drug would be negligible, and any difference noted between the two groups would be due to the cycloserine. The pyridoxine was given to lessen any possible side-effects which might be induced by the isoniazid. Some American workers have used pyridoxine in an attempt to reduce toxic effects due to cycloserine (Raleigh, 1959). One of the notable features in many reports on the clinical effect of cycloserine has been gain in weight (Grove-White and Supramaniam, 1958; Ritchie and others, 1958; Leites, 1959). Our results support the findings of these and other authors. Four patients in the cycloserine-isoniazid group, compared with one of the control gronp showed radiographic improvement. This improvement was unexpected because of the chronic nature of the disease. Leites reported 23 per cent of radiographic improvement in her patients under conditionrs very similar to ours. Leites also reported a 'reversal of infectiousness' in 21 per cent who had failed to respond to pro}onged treatment with other drugs. In our trial three out of thirteen underwent temporary 'sputum conversion', in the cycloserine group, while one patient in the control group had negative sputum throughout. These results point to a mild therapeutic response to cycloserine in chronic drug resistant pulmonary tuberculosis patients. Weinberger, Lindars, and Pasha (1958) expressed concern that tl~e therapeutically effective dose of cycloserine might be too close to the toxic dose for the drug to be used universally. On a dosage of 250 rag. twelve hourly only infrequent toxic effects were encountered in our trial and no serious neurotoxic effects occurred. With the exception of the three patients already described, the drug was continued for twelve months. As five patients complained of symptoms with serum cycloserine levels below 20 ~g./ml. the significance of the symptoms is questionable, particularly as five out of eight control group patients also complained of symptoms. Two of the latter complained with such persistance as to cause them to be withdrawn from the trial, yet both had taken isoniazid previously without ill-effect. Provided renal function was not impaired, as in one of our patients with amyloid disease, 250 rag. cycloserine twelve hourly proxcd a safe dose to give out-patients from the point of view of drug toxicity. On this dosage deterv ;ons of serum cycloserine levels are unnecessary, unless the patient complains of symptoms. It is now generally accepted that bacillary resistance to cycloscrine therapy develops slowly. Epstein and others (1958) in a trial of cycloserine-isoniazid on eighty-one newly diagnosed patients with pulmonary tuberculosis used the same dosage combination as in our trial. They concluded that from 0.5 g. of cycloserine a day there was no evidence of decreased bacillary sensitivity. As far as conclusions may be drawn from our results, cultures from two out of three of our patients with detailed sensitivity tests available showed a resistance eight times that of the control at twelve months, a degree of resistance which was maintained during the follow-up period. Our limited evidence would suggest that cycloserine should not be given on its own. Epstein and others (1958)
CYCLOSERINE TREATMENT IN DP, UG RESISTANT TUBERCULOSIS
13
s t a t e t h a t c y c l o s e r i n e a n d i s o n i a z i d w o r k s y n e r g i s t i c a l l y a n d in t h e i r series t w e n t y - n i n e o u t o f t h i r t y - f i v e p a t i e n t s w e r e p r o d u c i n g s p u t u m n e g a t i v e a t six m o n t h s . A s a l u t a r y c o n c l u s i o n o f the p a p e r , h o w e v e r , w a s the a u t h o r s ' s t a t e m e n t t h a t r e s i s t a n c e to i s o n i a z i d d e v e l o p e d at the s a m e rate a s t h a t seen w h e n i s o n i a z i d is g i v e n alone. w e wish to express our thanks to Dr. G. P. Maher Loughnan for his advice and help in drawing up our original protocol. Dr. Joanna Ward gave great assistance in collecting and analysing the results. Mrs. Halls, the clinic head clerk, controlled the allocation of treatment and the clinic staff rendered valuable assistance. M iss M. F. Crowley, B.Sc., was in charge of all biochemical investigations. We express our appreciation to her and to Mr. R. Amon and Miss E. Hutchinson for, technical bacteriological help. Finally we are grateful to Mr. E. A. G. Cook of Messrs. Eli Lilly & Co. Ltd. who provided us with all the capsules for this trial. REFERENCES CUMMINGS, M. M., PATNODE, R. A., & HUGGINS, P. C. (1955) Antibiot. & CIwmother., 5, 198. EPSTEIN, I. G., NAIR, K. G. S., & BOYD, L. J. (1955-56). Antibiot. Amt., 141. EeSTEIN, I. G., NAIR, K. G. S., & BOY~, L. J. (1956). Transactions of the 15th Conference on the CI]emotheraphy of Tuberculosis, p. 365, Veterans Administration, Washington. ErSTEIN, I. G., NATR, K. G. S., & BOYD, L. J. (1957). Amer. Rev. Tuberc., 75, 553. EPSTEIN, I. G., NAm, K. G. S., BOYD, L. J., & AUSlnTZ, P. (1958). Dis. Chest, 33, 371. GROVE-WHITE, R. J., & SUPRAMANIAM,J. M. J. (1958). Tubercle, Lond., 39, 213. HERROLO, R. D., BOAND, A. V., & KAMP, M. (1955-56). Antibiot. Ann., 655. HOLMES, C. X., MARTIN, G. E., & FETTERHOFF, K. I. (1959). Dis. Chest, 36, 591. LEITES, V. (1959). Amer. Rev. resp. Dis., 80, 89. LJLLICK, L., STRANG, R., BOYD, L. J., SCraWqMMER, M., & MULINOS, M. G. (1955-56). Antibiot. Amt.. 15~. MODAVE, J. (1957). Antibiot. Med., 4, 535. NASSAU, E. (1958). Tubercle, Lond., 39, J8. RALEtGH, J. W. (1959). Antibiot. Med., 6, 242. RENZETrl, A. D., WRIGHT, K. W., EDL~NG,J. H., & BONN, P. (1956). Amer. Rev. Tuberc., 74, 128. RtTCHIE, J. A., CAMPBELL,A. E. R., CUTHBERT, J., & BRUCE, L. G. (1958). Tubercle, Lond., 39, 289. WEINBERGER, M., LINDARS, D. C., & PASHA, M. A. (1958). Tubercle, Lond., 39, 96.