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The tuberculin test in pregnancy
The tuberculin test in pregnancy WILDER P. MONTGOMERY, M.D. ROSCOE C. YOUNG,
JR., M . D.
MARGARET P. ALLEN, R.N. K. ALBERT HARDEN, M.D., F.A.C.P . Washington, D. C. Of 2,357 Negro females tested for tuberculosis during the prenatal period, 9.6 per cent of them had positive reactions (a figure substantially less than that quoted for the gllneral population of thll District of Columbia). Excllpt for two known inactive cases of reinfection type tuberculosis, ·no new pulmonary lesions of Ihis Iype were found on subS/lquent x-ray. Thlls/l results compar. favorably with earlier investigations. In a limited study, variation in the amount of luberculin r.action in women in Ihe pr,gnant and nonpregnant states appear,d to parallel the fluctuations found in nonpregnant individuals. Tub,rculin tesling of pregnant womllR is still a valid and most feasible method of cas, finding and should be conlinued as loog as the incidenc, of posilive reaclors indicales a significant reservoir of preinfeclion. Our findings over a 6 year span sugg,SI a d,creas, in th, thl number of pregnant wom,n who wer, al some time infected by tuberculosis.
I N 1 9 4 0, Maeder and Myers1 stated, "The examination of the woman who presents herself for obstetric care should include the tuberculin test just as certainly as it should include a test for syphilis." They had in mind, of course, the economy of its use in a screening program, emphasizing that negative reactors were sufficiently numerous to make it a desirable procedure. Today, although the exposure to radiation in taking a chest x-ray is minimal (and perhaps negligible2 ) , it possibly assumes additional importance against a background of increasing world radiation at an uncontrolled and unpredictable rate, and when it is unknown at which point mutations may occur. These two factors, in any event, are offered in support of a case finding method which may, in fact, fail to uncover a minimal number of active cases of tuberculosis. a
M.thods This study covers the routine tuberculin testing (with chest x-rays of positive reacFrom Ih, Pulmonary Dis,as' Division, Howard UniliITsi/y alld F".dm.n', Hospital.
tors) of pregnant women from Freedmen's Hospital Prenatal Clinic during the period from May, 1960, to September, 1966. The study was divided into two 3 year periods, in order to permit us to follow-up the first three year group for overt tuberculosis. The senior member of our group recalled that the impression imparted by the older literature had been of the unreliability of the tuberculin test performed on pregnant women. For example, Poncher: in 1941, noted that "cutaneous reactivity may be depressed during menstruation, pregnancy, and lactation." In view of the later knowledge of steroids and pregnancy,5, I, T it would not be surprising that some depression should occur. To check on this point, the 142 pregnant Negro women who had positive tuberculin reactions that were found from May, 1960, to June, 1963, were asked to return for retesting beyond the postpartum period. We realized that these were, in the main, disadvantaged people now burdened with an infant or in· fants, and we anticipated their response might not be encouraging. We were able to repeat twenty-three tests with readings. All
830
Montgomery et 01.
Am.
Table I. Tuberculin skin tests during pregnancy and following delivery Case no. 1
2 3 4 5 6
7 8 9 10 11
12 13 14 15 16 17 18 19 20 21 22 23
During pregnancy
After delivery
15*
13
10 10 10 10 15 13 20 15 16 15 10
Negative
14
10
16 20 17 27 20 17 15
14
16
11
21
Negative 17 22 21 25 20
Negative 10 16 10 10 20 16 26 12 19 14
15 16
-Diameter of induration measured in millimeters.
testing and readings were done by a single observer (with 18 years' experience) or by her assistant (with 7 years' experience). In a series run for comparable reading reproducibility, these two rarely varied by more than a millimeter. The standard intermediate strength P.P.D. (0.0001 mg.) was used. Tests that varied less than 2 mm. were considered unchanged. None of the women retested were lactating. We lack data on their menstrual status at the time of retesting.
R.sults Five of these 23 patients retested showed decreased reactions. Three patients had negative reactions on retesting, 2 from 10 nun. and one from 16 nun. Seven patients' results were unchanged, while 8 showed increased reactions (Table I). Of the total of 1,710 pregnant women seen between May, 1960, and June, 1963, 142 had positive tuberculin test results. Of the total group, 216 (13 per cent) failed to return for skin test readings. Because of extensive dennatitis, 2 were excluded from
March 15, 1968 &: Gynec.
J. Obat.
tuberculin testing, and another 22 were left out because they were known to have had positive reactions. Of the latter, 2 had inactive pulmonary tuberculosis (previously treated by chemotherapy and with residua classified as moderately advanced and minimal, respectively). Two were not tested since they had current negative reactions when they were checked elsewhere. There were, thus, 164 positive reactors (approximately 11 per cent). All of these received chest x-rays (with abdominal shielding when done in the prenatal period). No new reinfection tuberculosis was found, so that there were only the 2 known inactive cases. The incidence of demonstrable reinfection tuberculosis was then 1.2 per cent, but for previously unknown reinfection tuberculosis, it was zero. In addition, we attempted to ascertain whether any of the positive reactors developed clinical tuberculosis after a 3 year period, as determined from our clinic files and a search of the District of Columbia Tuberculosis Registry.*t None apparently did. The 2 known inactive cases were still stable. An additional 933 tuberculin tests of pregnant women were administered from June, 1963, to September, 1966. Of these, 68 (7 per cent) did not return. There were 865 readings with a positive reaction in 72 (8 per cent). All of these received chest x-rays. No reinfection lesions were found. Comment
No definite pattern was discernible in the tuberculin tests, whether prenatal or post partum. Only 4 cases showed decreased induration of more than 5 mm.; 5 showed increased induration of more than 5 nun. The 3 revenions to negative tend to indicate further that what we have found is the normal fluctuation in tuberculin reactivity as
o'
"ThrOUlh the kiadMa Mn. K. V. Burke, Director, D. C., Tuberculolia RePtry. tsince these women would nol be financially prepared .. have tuberculooil treated privale1y, and .inee our Freedmen'. Hoopital or the Health Deparlmeal would treat Ibeaa, _ 'eel IhiI -1hocIoIosY bu presenled a reuonably IICCI&J'aIe pieture.
Volume 100 Number 6
seen in the nonpregnant individual, which was well delineated by Mascher. 8 Comparison of our cases with earlier studies. In 1938, Eisele and MasonS reported the incidence of unsuspected tuberculosis in the routine prenatal clinic to be 1.06 per cent in a series of 4,040 cases routinely fluoroscoped from 1934 to 1937 in Chicago. They preferred fluoroscopy to tuberculin testing on two counts. They feared their patients would not return for reading, and they felt that adult positive reactors were too numerous to make skin testing a desirable screening procedure. In 1939, Ianne and Muir 9 reported upon tuberculin tests in 805 pregnant women. Of this group, 114 (14 per cent) failed to return for tuberculin readings. Of the 691 women whose tests were read, 284 (41 per cent) were positive. Of these, 252 had chest x-rays. Twelve (1. 7 per cent) had active reinfection tuberculosis. In 1940, Maeder and Myers l reported upon their examination by skin test of 2,350 pregnant women. Eighteen (0.7 per cent) did not return for readings. There were 841 positive reactors, an incidence of 36 per cent. All had chest films. There were 26 probable reinfection type lesions, 3 per cent of the positive reactors. Now, although it is not news that the incidence of tuberculosis has shown a marked
Tuberculin test in pregnancy
831
decrease, it is gratifying to find, in a formerly high incidence group (young Negro pregnant women), only 9.6 per cent of them were tuberculin positive, with no reinfection tuberculosis other than the two known inactive cases. This was in the period May, 1960, to September, 1966, and embraced 2,357 adequately examined women. It may be noted that this incidence of positive reactors is considerably below that quoted by the Tuberculosis Association for the District of Columbia population as a whole (about 25 per cent). Conclusions 1. In a limited study, variation in the amount of tuberculin reaction in women in the pregnant and nonpregnant states appeared to parallel the fluctuations found in nonpregnant individuals. 2. Tuberculin testing of pregnant women is still a valid and most feasible method of case finding and should be continued as long as the incidence of positive reactors indicates a significant reservoir of preinfection. 3. That portion of our series from 1963 to 1966 suggests that the number of those at some time infected by tuberculosis (8.7 per cent tuberculin positive for the second 3 year period, as against 11 per cent for the first 3 years) is further decreasing.
REFERENCES
1. Maeder, E. C., and Myen, J. A.: AM. J. OBST. &: GVNEC. 40: 21B, 1940. 2. Skarn, J. H., and Gerbie, A. B.: M. Clin. North America 45: 127, 1961. 3. Mascher, W.: Am. Rev. Tuberc. 63: 501, 1951. 4. Poncher, H.: Sources of Error in the Clinical Interpretation of the Tuberculin Reaction, in Goldberg, B., editor: Clinical Tuberculosis, Philadelphia, 1941, F. A. Davis Company, p. E-51.
5. Venning, E. H.: Endocrinology 39: 203, 1946. 6. Hench, P. S., Kendall, E. C., Slocumb, C. H., and Polley, H. F.: Proc. Staff Meet., Mayo Clin. 24: IBl, 1949. 7. Salomon, H., and Angel, J. H.: Am. Rev. Reap. Dis. 83: 235, 1961. 8. Eisele, C. W., and MalOn, E. W.: AM. J. OBST. &: GVNEO. 36: 387, 1938. 9. lanne, C. L., and Muir, J. C.: AM. J. OBST. &: GVNEC. 38: 448, 1939.
JR., M . D.
MARGARET P. ALLEN, R.N. K. ALBERT HARDEN, M.D., F.A.C.P . Washington, D. C. Of 2,357 Negro females tested for tuberculosis during the prenatal period, 9.6 per cent of them had positive reactions (a figure substantially less than that quoted for the gllneral population of thll District of Columbia). Excllpt for two known inactive cases of reinfection type tuberculosis, ·no new pulmonary lesions of Ihis Iype were found on subS/lquent x-ray. Thlls/l results compar. favorably with earlier investigations. In a limited study, variation in the amount of luberculin r.action in women in Ihe pr,gnant and nonpregnant states appear,d to parallel the fluctuations found in nonpregnant individuals. Tub,rculin tesling of pregnant womllR is still a valid and most feasible method of cas, finding and should be conlinued as loog as the incidenc, of posilive reaclors indicales a significant reservoir of preinfeclion. Our findings over a 6 year span sugg,SI a d,creas, in th, thl number of pregnant wom,n who wer, al some time infected by tuberculosis.
I N 1 9 4 0, Maeder and Myers1 stated, "The examination of the woman who presents herself for obstetric care should include the tuberculin test just as certainly as it should include a test for syphilis." They had in mind, of course, the economy of its use in a screening program, emphasizing that negative reactors were sufficiently numerous to make it a desirable procedure. Today, although the exposure to radiation in taking a chest x-ray is minimal (and perhaps negligible2 ) , it possibly assumes additional importance against a background of increasing world radiation at an uncontrolled and unpredictable rate, and when it is unknown at which point mutations may occur. These two factors, in any event, are offered in support of a case finding method which may, in fact, fail to uncover a minimal number of active cases of tuberculosis. a
M.thods This study covers the routine tuberculin testing (with chest x-rays of positive reacFrom Ih, Pulmonary Dis,as' Division, Howard UniliITsi/y alld F".dm.n', Hospital.
tors) of pregnant women from Freedmen's Hospital Prenatal Clinic during the period from May, 1960, to September, 1966. The study was divided into two 3 year periods, in order to permit us to follow-up the first three year group for overt tuberculosis. The senior member of our group recalled that the impression imparted by the older literature had been of the unreliability of the tuberculin test performed on pregnant women. For example, Poncher: in 1941, noted that "cutaneous reactivity may be depressed during menstruation, pregnancy, and lactation." In view of the later knowledge of steroids and pregnancy,5, I, T it would not be surprising that some depression should occur. To check on this point, the 142 pregnant Negro women who had positive tuberculin reactions that were found from May, 1960, to June, 1963, were asked to return for retesting beyond the postpartum period. We realized that these were, in the main, disadvantaged people now burdened with an infant or in· fants, and we anticipated their response might not be encouraging. We were able to repeat twenty-three tests with readings. All
830
Montgomery et 01.
Am.
Table I. Tuberculin skin tests during pregnancy and following delivery Case no. 1
2 3 4 5 6
7 8 9 10 11
12 13 14 15 16 17 18 19 20 21 22 23
During pregnancy
After delivery
15*
13
10 10 10 10 15 13 20 15 16 15 10
Negative
14
10
16 20 17 27 20 17 15
14
16
11
21
Negative 17 22 21 25 20
Negative 10 16 10 10 20 16 26 12 19 14
15 16
-Diameter of induration measured in millimeters.
testing and readings were done by a single observer (with 18 years' experience) or by her assistant (with 7 years' experience). In a series run for comparable reading reproducibility, these two rarely varied by more than a millimeter. The standard intermediate strength P.P.D. (0.0001 mg.) was used. Tests that varied less than 2 mm. were considered unchanged. None of the women retested were lactating. We lack data on their menstrual status at the time of retesting.
R.sults Five of these 23 patients retested showed decreased reactions. Three patients had negative reactions on retesting, 2 from 10 nun. and one from 16 nun. Seven patients' results were unchanged, while 8 showed increased reactions (Table I). Of the total of 1,710 pregnant women seen between May, 1960, and June, 1963, 142 had positive tuberculin test results. Of the total group, 216 (13 per cent) failed to return for skin test readings. Because of extensive dennatitis, 2 were excluded from
March 15, 1968 &: Gynec.
J. Obat.
tuberculin testing, and another 22 were left out because they were known to have had positive reactions. Of the latter, 2 had inactive pulmonary tuberculosis (previously treated by chemotherapy and with residua classified as moderately advanced and minimal, respectively). Two were not tested since they had current negative reactions when they were checked elsewhere. There were, thus, 164 positive reactors (approximately 11 per cent). All of these received chest x-rays (with abdominal shielding when done in the prenatal period). No new reinfection tuberculosis was found, so that there were only the 2 known inactive cases. The incidence of demonstrable reinfection tuberculosis was then 1.2 per cent, but for previously unknown reinfection tuberculosis, it was zero. In addition, we attempted to ascertain whether any of the positive reactors developed clinical tuberculosis after a 3 year period, as determined from our clinic files and a search of the District of Columbia Tuberculosis Registry.*t None apparently did. The 2 known inactive cases were still stable. An additional 933 tuberculin tests of pregnant women were administered from June, 1963, to September, 1966. Of these, 68 (7 per cent) did not return. There were 865 readings with a positive reaction in 72 (8 per cent). All of these received chest x-rays. No reinfection lesions were found. Comment
No definite pattern was discernible in the tuberculin tests, whether prenatal or post partum. Only 4 cases showed decreased induration of more than 5 mm.; 5 showed increased induration of more than 5 nun. The 3 revenions to negative tend to indicate further that what we have found is the normal fluctuation in tuberculin reactivity as
o'
"ThrOUlh the kiadMa Mn. K. V. Burke, Director, D. C., Tuberculolia RePtry. tsince these women would nol be financially prepared .. have tuberculooil treated privale1y, and .inee our Freedmen'. Hoopital or the Health Deparlmeal would treat Ibeaa, _ 'eel IhiI -1hocIoIosY bu presenled a reuonably IICCI&J'aIe pieture.
Volume 100 Number 6
seen in the nonpregnant individual, which was well delineated by Mascher. 8 Comparison of our cases with earlier studies. In 1938, Eisele and MasonS reported the incidence of unsuspected tuberculosis in the routine prenatal clinic to be 1.06 per cent in a series of 4,040 cases routinely fluoroscoped from 1934 to 1937 in Chicago. They preferred fluoroscopy to tuberculin testing on two counts. They feared their patients would not return for reading, and they felt that adult positive reactors were too numerous to make skin testing a desirable screening procedure. In 1939, Ianne and Muir 9 reported upon tuberculin tests in 805 pregnant women. Of this group, 114 (14 per cent) failed to return for tuberculin readings. Of the 691 women whose tests were read, 284 (41 per cent) were positive. Of these, 252 had chest x-rays. Twelve (1. 7 per cent) had active reinfection tuberculosis. In 1940, Maeder and Myers l reported upon their examination by skin test of 2,350 pregnant women. Eighteen (0.7 per cent) did not return for readings. There were 841 positive reactors, an incidence of 36 per cent. All had chest films. There were 26 probable reinfection type lesions, 3 per cent of the positive reactors. Now, although it is not news that the incidence of tuberculosis has shown a marked
Tuberculin test in pregnancy
831
decrease, it is gratifying to find, in a formerly high incidence group (young Negro pregnant women), only 9.6 per cent of them were tuberculin positive, with no reinfection tuberculosis other than the two known inactive cases. This was in the period May, 1960, to September, 1966, and embraced 2,357 adequately examined women. It may be noted that this incidence of positive reactors is considerably below that quoted by the Tuberculosis Association for the District of Columbia population as a whole (about 25 per cent). Conclusions 1. In a limited study, variation in the amount of tuberculin reaction in women in the pregnant and nonpregnant states appeared to parallel the fluctuations found in nonpregnant individuals. 2. Tuberculin testing of pregnant women is still a valid and most feasible method of case finding and should be continued as long as the incidence of positive reactors indicates a significant reservoir of preinfection. 3. That portion of our series from 1963 to 1966 suggests that the number of those at some time infected by tuberculosis (8.7 per cent tuberculin positive for the second 3 year period, as against 11 per cent for the first 3 years) is further decreasing.
REFERENCES
1. Maeder, E. C., and Myen, J. A.: AM. J. OBST. &: GVNEC. 40: 21B, 1940. 2. Skarn, J. H., and Gerbie, A. B.: M. Clin. North America 45: 127, 1961. 3. Mascher, W.: Am. Rev. Tuberc. 63: 501, 1951. 4. Poncher, H.: Sources of Error in the Clinical Interpretation of the Tuberculin Reaction, in Goldberg, B., editor: Clinical Tuberculosis, Philadelphia, 1941, F. A. Davis Company, p. E-51.
5. Venning, E. H.: Endocrinology 39: 203, 1946. 6. Hench, P. S., Kendall, E. C., Slocumb, C. H., and Polley, H. F.: Proc. Staff Meet., Mayo Clin. 24: IBl, 1949. 7. Salomon, H., and Angel, J. H.: Am. Rev. Reap. Dis. 83: 235, 1961. 8. Eisele, C. W., and MalOn, E. W.: AM. J. OBST. &: GVNEO. 36: 387, 1938. 9. lanne, C. L., and Muir, J. C.: AM. J. OBST. &: GVNEC. 38: 448, 1939.