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THE ROUTE OF INFECTION IN POLIOMYELITIS
THE ROUTE OF INFECTION IN POLIOMYELITIS
may be tortuous. Other congenital defects-especially Fallot’s tetralogy-are often associated with a right-sided arch, and the appearances peculiar to them will then be added. The symptoms, which are not constant, are the result of local pressure, and are likely to lead to suspicion of growth, intrathoracic goitre, or aneurysm. Bedford and Parkinson’s study is based on 11 cases and attention to the points they raise should lead to correct diagnosis of this
interesting congenital anomaly. THE ROUTE OF INFECTION IN POLIOMYELITIS
authorities hold that the portal of infection is the nasopharynx-at any rate in the great majority of cases-and that the virus reaches the central nervous system by passing along the olfactory nerves, after which its spread to the cord is axonal. Briefly stated, the evidence in support of this conception is as follows. The virus of poliomyelitis is highly neurotropic ; nerve-cells are essential for its multiplication. In poliomyelitis the virus is found in the nasopharynx and in the central nervous system ; it does not appear in demonstrable quantity either in the blood or in the cerebro-spinal fluid. If monkeys are infected by the cerebral route and the course taken by the virus in its spread thence to the anterior horn cells is followed, as Fairbrother MOST
.
in poliomyelitis
given intravenously.
455
They thought
that
virus
introduced into the circulation reached the central nervous system by being excreted on to the nasopharyngeal mucosa and then passing inwards along the olfactory nerves, but the experiments of Sabin and Olitsky seem to show that this is not always so. The work of Sabin and Olitsky does not merely give additional support to the theory of axonal spread ; it goes some way to answer the question of the importance of the nasopharynx as the portal of infection in human poliomyelitis. If experimental poliomyelitis in the monkey is comparable to the human disease, then a study of the olfactory bulbs should tell us how often the virus enters the body by the nasopharyngeal route. Apparently there are very few observations on the incidence of lesions in the olfactory bulbs in poliomyelitis, and this gap in our knowledge will surely be rectified at the first opportunity-
BASOPHIL CARCINOMA OF THE PITUITARY GLAND WITH CUSHING’S SYNDROME
ALTHOUGH primary tumours of the anterior lobe of the pituitary gland often invade surrounding structures they very rarely give rise to metastases to remoter parts. Prof. Cohen and Prof. Dible1 now report a case of Cushing’s syndrome in association with a metastasising basophil carcinoma, and and Hurstand Faber and Gebhardthave followed this is probably the first of its kind to be recorded. patient was an unmarried woman of 50 and the it, the evidence obtained suggests axonal spread. The disturbance referable to the pituitary tumour clinical And lastly if the olfactory bulbs are destroyed then, began seven years before death. Examination as Schultz 3 has shown, the monkey becomes insusceptible to infection by the nasal route. Recent work about eighteen months before death revealed the clinical features of the syndrome. by A. B. Sabin and P. K. Olitsky4 provides an characteristic the to authors all features were present According important addition to this evidence. They argued but analysis of previously except polycythaemia; that if the virus reached the central nervous system recorded cases shows that this is a questionable the by way of olfactory nerves one might expect element of Cushing’s syndrome. Of the other the olfactory bulbs to be the seat of early and concharacteristic features all but amenorrhoea and stant change, and they carried out experiments to seem to have been clearly established. Amenorobesity see if this was so. Working with the M.V. strain of rhcea in a woman of 48, even though unattended by virus and having ascertained the dosage necessary is of course conspicuous menopausal any symptoms, via the studied to infect nose, they monkeys regularly of doubtful the seems to have significance ; obesity the olfactory bulbs in animals so inoculated. The been transient. examination of the urine Biological first rise of temperature in their infected monkeys for sex hormones yielded completely negative results. occurred 4-6 days after inoculation, paralysis appearTreatment of the pituitary region with X rays was ing in another three days. In monkeys killed and followed by an improvement which lasted for a examined on the fourth day the outer layers of the little over a year, but relapse then rapidly led to olfactory bulbs showed diffuse infiltration with the pituitary gland was greatly polymorphonuclear leucocytes, mononuclear cells, and death. At necropsy a lobulated basophilic tumour of the expanded by mitral cells were frequently lymphocytes, and the necrotic. At this time lesions were present in the anterior lobe. Cohen and Dible’s statement that change described by Crooke in the cytomesencephalon and pons but were absent from the the hyaline of the plasm basophil cells was not found in their cord. Later when paralysis had supervened the is case as not, might at first appear, a refutation of changes in the olfactory bulbs were more conspicuous Crooke’s observation. Their description is confined and well-developed cuffing of the vessels was observed. to the tumour cells; they do not describe the Lesions of varying extent were found in the olfactory the of basophil cells in such remnants appearances bulbs in every one of 18 monkeys infected by the of anterior lobe as may have been present in their the nasal route. They were absent in 13 monkeys infected preparations. According to Crooke2 this change by other routes, such as the cerebral, subcutaneous, is always found in the basophil cells of the anterior ocular, or sciatic. It is noteworthy that Sabin and lobe proper and only occasionally in the cells of any Olitsky only found lesions in the olfactory bulbs in tumour. In this connexion it is noteworthy that one of three monkeys infected by intravenous injection. Lennette and Hudson 5 produced evidence Rasmussen3 has lately confirmed the presence of that destruction of the olfactory bulbs protects the this hyaline change in three additional cases of syndrome. The first was in a woman monkey against infection with poliomyelitis virus Cushing’s aged 27 who had a large, not definitely basophilic, The second, in a woman tumour of the anterior lobe. 1 Fairbrother, R. W., and Hurst, E. W. (1930) J. Path. Bact. is in no tumour was found remarkable that 33, 17. 44, aged Faber, H. K., and Gebhardt, L. P. (1933) J. exp. Med. 57, in either the or suprarenal bodies ; there pituitary 933. was no hyperplasia of the suprarenal cortex. The 3 Schultz, E. W., and Gebhardt, L. P. (1934) Proc. Soc. exp. 2
Biol., N.Y. 31, 728. 4 Sabin, A. B., and Olitsky, P. K. (1937) J. Amer. med. Ass. 21. 108, 5 Lennette, E. H., and Hudson, N. P. (1935) Proc. Soc. exp. Biol., N.Y. 32, 1444.
1 Cohen, H., and Dible, J. H. (1936) Brain, 59, 2
395.
Crooke, A. C. (1935) J. Path. Bact. 41, 339. 3 Rasmussen, A. T. (1936) Endocrinology, 20, 673.
may be tortuous. Other congenital defects-especially Fallot’s tetralogy-are often associated with a right-sided arch, and the appearances peculiar to them will then be added. The symptoms, which are not constant, are the result of local pressure, and are likely to lead to suspicion of growth, intrathoracic goitre, or aneurysm. Bedford and Parkinson’s study is based on 11 cases and attention to the points they raise should lead to correct diagnosis of this
interesting congenital anomaly. THE ROUTE OF INFECTION IN POLIOMYELITIS
authorities hold that the portal of infection is the nasopharynx-at any rate in the great majority of cases-and that the virus reaches the central nervous system by passing along the olfactory nerves, after which its spread to the cord is axonal. Briefly stated, the evidence in support of this conception is as follows. The virus of poliomyelitis is highly neurotropic ; nerve-cells are essential for its multiplication. In poliomyelitis the virus is found in the nasopharynx and in the central nervous system ; it does not appear in demonstrable quantity either in the blood or in the cerebro-spinal fluid. If monkeys are infected by the cerebral route and the course taken by the virus in its spread thence to the anterior horn cells is followed, as Fairbrother MOST
.
in poliomyelitis
given intravenously.
455
They thought
that
virus
introduced into the circulation reached the central nervous system by being excreted on to the nasopharyngeal mucosa and then passing inwards along the olfactory nerves, but the experiments of Sabin and Olitsky seem to show that this is not always so. The work of Sabin and Olitsky does not merely give additional support to the theory of axonal spread ; it goes some way to answer the question of the importance of the nasopharynx as the portal of infection in human poliomyelitis. If experimental poliomyelitis in the monkey is comparable to the human disease, then a study of the olfactory bulbs should tell us how often the virus enters the body by the nasopharyngeal route. Apparently there are very few observations on the incidence of lesions in the olfactory bulbs in poliomyelitis, and this gap in our knowledge will surely be rectified at the first opportunity-
BASOPHIL CARCINOMA OF THE PITUITARY GLAND WITH CUSHING’S SYNDROME
ALTHOUGH primary tumours of the anterior lobe of the pituitary gland often invade surrounding structures they very rarely give rise to metastases to remoter parts. Prof. Cohen and Prof. Dible1 now report a case of Cushing’s syndrome in association with a metastasising basophil carcinoma, and and Hurstand Faber and Gebhardthave followed this is probably the first of its kind to be recorded. patient was an unmarried woman of 50 and the it, the evidence obtained suggests axonal spread. The disturbance referable to the pituitary tumour clinical And lastly if the olfactory bulbs are destroyed then, began seven years before death. Examination as Schultz 3 has shown, the monkey becomes insusceptible to infection by the nasal route. Recent work about eighteen months before death revealed the clinical features of the syndrome. by A. B. Sabin and P. K. Olitsky4 provides an characteristic the to authors all features were present According important addition to this evidence. They argued but analysis of previously except polycythaemia; that if the virus reached the central nervous system recorded cases shows that this is a questionable the by way of olfactory nerves one might expect element of Cushing’s syndrome. Of the other the olfactory bulbs to be the seat of early and concharacteristic features all but amenorrhoea and stant change, and they carried out experiments to seem to have been clearly established. Amenorobesity see if this was so. Working with the M.V. strain of rhcea in a woman of 48, even though unattended by virus and having ascertained the dosage necessary is of course conspicuous menopausal any symptoms, via the studied to infect nose, they monkeys regularly of doubtful the seems to have significance ; obesity the olfactory bulbs in animals so inoculated. The been transient. examination of the urine Biological first rise of temperature in their infected monkeys for sex hormones yielded completely negative results. occurred 4-6 days after inoculation, paralysis appearTreatment of the pituitary region with X rays was ing in another three days. In monkeys killed and followed by an improvement which lasted for a examined on the fourth day the outer layers of the little over a year, but relapse then rapidly led to olfactory bulbs showed diffuse infiltration with the pituitary gland was greatly polymorphonuclear leucocytes, mononuclear cells, and death. At necropsy a lobulated basophilic tumour of the expanded by mitral cells were frequently lymphocytes, and the necrotic. At this time lesions were present in the anterior lobe. Cohen and Dible’s statement that change described by Crooke in the cytomesencephalon and pons but were absent from the the hyaline of the plasm basophil cells was not found in their cord. Later when paralysis had supervened the is case as not, might at first appear, a refutation of changes in the olfactory bulbs were more conspicuous Crooke’s observation. Their description is confined and well-developed cuffing of the vessels was observed. to the tumour cells; they do not describe the Lesions of varying extent were found in the olfactory the of basophil cells in such remnants appearances bulbs in every one of 18 monkeys infected by the of anterior lobe as may have been present in their the nasal route. They were absent in 13 monkeys infected preparations. According to Crooke2 this change by other routes, such as the cerebral, subcutaneous, is always found in the basophil cells of the anterior ocular, or sciatic. It is noteworthy that Sabin and lobe proper and only occasionally in the cells of any Olitsky only found lesions in the olfactory bulbs in tumour. In this connexion it is noteworthy that one of three monkeys infected by intravenous injection. Lennette and Hudson 5 produced evidence Rasmussen3 has lately confirmed the presence of that destruction of the olfactory bulbs protects the this hyaline change in three additional cases of syndrome. The first was in a woman monkey against infection with poliomyelitis virus Cushing’s aged 27 who had a large, not definitely basophilic, The second, in a woman tumour of the anterior lobe. 1 Fairbrother, R. W., and Hurst, E. W. (1930) J. Path. Bact. is in no tumour was found remarkable that 33, 17. 44, aged Faber, H. K., and Gebhardt, L. P. (1933) J. exp. Med. 57, in either the or suprarenal bodies ; there pituitary 933. was no hyperplasia of the suprarenal cortex. The 3 Schultz, E. W., and Gebhardt, L. P. (1934) Proc. Soc. exp. 2
Biol., N.Y. 31, 728. 4 Sabin, A. B., and Olitsky, P. K. (1937) J. Amer. med. Ass. 21. 108, 5 Lennette, E. H., and Hudson, N. P. (1935) Proc. Soc. exp. Biol., N.Y. 32, 1444.
1 Cohen, H., and Dible, J. H. (1936) Brain, 59, 2
395.
Crooke, A. C. (1935) J. Path. Bact. 41, 339. 3 Rasmussen, A. T. (1936) Endocrinology, 20, 673.