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POLIOMYELITIS AND TOXOCARA INFECTION
27
tion of 1-in-30 savlon in distilled water. It has long been known that pH can influence the activity of disinfectants; but that a seemingly trivial change in reaction can produce a qualitative change is a point worth consideration not only in the preparation of solutions but also in laboratory testing of disinfectants and the selection of products for different hospital
Poliomyelitis is no longer a serious problem in Britain. Nevertheless, other enteroviruses still spread freely in the community, and concomitant helminth infection may conceivably facilitate transmission of these viruses from the intestinal tract to other tissues, including the central nervous system.
uses.
The chief influence determining which microare concerned in hospital-acquired infection is the pattern of antibiotic use in the hospital. Since the advent of the penicillinase-resistant penicillins there has been a swing from staphylococcal infection to infection with klebsiella, enterobacter, serratia, and pseudomonas. Although the antibiotic resistance of Ps. cepacia is remarkable, and includes drugs active against Ps. æruginosa (carbenicillin, colistin, and gentamicin), it was plainly not this property, but the ability to adapt to certain disinfectants and multiply in them, that made possible its role in hospital infection. Antibiotics have certainly been more important in the selection of the other
organisms
gram-negative organisms now commonly responsible for hospital infections, but widely used and misused disinfectants may well have played a part.
FUNGAL SEPTICAEMIA COMPLICATING INTRAVENOUS HYPERALIMENTATION
DURING
33 patients the University of 22 of them had received parenteral hyperalimentation (infusions of aminoacid solutions with sugar or alcohol) for severe gastrointestinal dysfunction. In this group the septicxmia was not related to steroid therapy or immunological deficiency, but all the patients had had intravenous catheters for long periods. Much the commonest infecting microorganism was Candida albicans, which was responsible for the septicaemia of 17 of the 22 patients. Torulopsis glabrata was found in 3 and C. parakrusei in 2. Cultures were taken from twelve of the catheter-tips, and in each the same fungal species grew as had been isolated from the blood. As would be expected, the incidence of septicaemia was related both to the duration of hyperalimentation and to the time since the last catheter an
eighteen-month period,
with fungal septicaemia Minnesota Hospital.1
were seen at
POLIOMYELITIS AND TOXOCARA INFECTION
change.
poliovirus infections are confined to the intestinal tract and produce no symptoms. How often
In a prospective investigation in the same unit, septicaemia complicated therapy in 13 of the 49 patients receiving parenteral hyperalimentation. In 8 of these, C. albicans was the causal organism. In several patients culture of the intravenous fluid was attempted
MOST
viræmia follows intestinal infection is not known for certain, but invasion of the central nervous system is rare. Paralysis results from perhaps one in every hundred infections with a virulent virus, and much less frequently with avirulent strains. Why is the central nervous system so seldom invaded ? The answer is not clear; but local irritation, such as that caused by some adjuvant-type vaccines, is believed to increase the susceptibility of the part of the spinal cord that supplies the infected area. Khalil and his colleagues’ have now shown that Egyptian children with poliomyelitis are more likely to show serological evidence of infection with Toxocara canis than the normal population-the prevalence of helminth infection in the two groups being 5-8% and 1-4%, respectively. This confirms the previous observations of Woodruff et a1. in Britain. There is not necessarily a direct relation between toxocara infection and poliomyelitis-the association may merely reflect similar standards of hygiene of those affected. Woodruff has suggested that toxocara larvm may act as vehicles, conveying additional amounts of virus from the lumen of the alimentary tract to the blood and through it to other tissues such as the central nervous system. It is also possible that the irritation resulting from intestinal infestation encourages invasion of the spinal cord in much the same way as adjuvant vaccines. 1.
2.
Khalil, H. M., Khattab, A. K., El-Fattah, S. M. A., Khalid, M. L., Awaad, S., Rifaat, M. A. Trans. R. Soc. trop. Med. Hyg. 1971, 65, 599. Woodruff, A. W., Bisseru, B., Dowe, J. C. Br. med. J. 1966, i, 1576.
the onset of fever, with negative results. The Minneapolis workers investigated the possibility that the glucose in the hyperalimentation fluid might have adversely affected the phagocytic powers of the hosts’ at
polymorphs, impairing their capacity to deal with the invading fungi. No evidence of this was found. Undoubtedly this dangerous complication of hyperalimentation also occurs in other hospitals. An inherent difficulty is that, by definition, parenteral hyperalimentation fluids are very nutritious; they contain high concentrations of glucose and are bound to support the growth of a wide variety of microorganisms, including pathogenic fungi. There is at present no safe method of preventing these infections. Antibacterial antibiotic ointments may be used the
infusion-sites, but would not control the fungus species. The Minneapolis workers do not seem to have tried antifungal antibiotic ointments, or prophylactic intravenous antifungal antibiotics. No doubt they thought that these would be too dangerous in patients already severely ill. Their findings highlight the need for aseptic methods of parenteral feeding. External arteriovenous shunts may be an at
answer.2,33 Curry, E. R., Quie, P. G. New Engl. J. Med. 1971, 285, 1221. Scribner, B. H., Cole, J. J., Christopher, T. G., Vizzo, J. E., Atkins, R. C., Blagg, C. R. J. Am. med. Ass. 1970, 212, 457. 3. Shils, M. E., Wright, W. L., Turnbull, A., et al. New Engl. J. Med. 1970, 283, 341.
1. 2.
tion of 1-in-30 savlon in distilled water. It has long been known that pH can influence the activity of disinfectants; but that a seemingly trivial change in reaction can produce a qualitative change is a point worth consideration not only in the preparation of solutions but also in laboratory testing of disinfectants and the selection of products for different hospital
Poliomyelitis is no longer a serious problem in Britain. Nevertheless, other enteroviruses still spread freely in the community, and concomitant helminth infection may conceivably facilitate transmission of these viruses from the intestinal tract to other tissues, including the central nervous system.
uses.
The chief influence determining which microare concerned in hospital-acquired infection is the pattern of antibiotic use in the hospital. Since the advent of the penicillinase-resistant penicillins there has been a swing from staphylococcal infection to infection with klebsiella, enterobacter, serratia, and pseudomonas. Although the antibiotic resistance of Ps. cepacia is remarkable, and includes drugs active against Ps. æruginosa (carbenicillin, colistin, and gentamicin), it was plainly not this property, but the ability to adapt to certain disinfectants and multiply in them, that made possible its role in hospital infection. Antibiotics have certainly been more important in the selection of the other
organisms
gram-negative organisms now commonly responsible for hospital infections, but widely used and misused disinfectants may well have played a part.
FUNGAL SEPTICAEMIA COMPLICATING INTRAVENOUS HYPERALIMENTATION
DURING
33 patients the University of 22 of them had received parenteral hyperalimentation (infusions of aminoacid solutions with sugar or alcohol) for severe gastrointestinal dysfunction. In this group the septicxmia was not related to steroid therapy or immunological deficiency, but all the patients had had intravenous catheters for long periods. Much the commonest infecting microorganism was Candida albicans, which was responsible for the septicaemia of 17 of the 22 patients. Torulopsis glabrata was found in 3 and C. parakrusei in 2. Cultures were taken from twelve of the catheter-tips, and in each the same fungal species grew as had been isolated from the blood. As would be expected, the incidence of septicaemia was related both to the duration of hyperalimentation and to the time since the last catheter an
eighteen-month period,
with fungal septicaemia Minnesota Hospital.1
were seen at
POLIOMYELITIS AND TOXOCARA INFECTION
change.
poliovirus infections are confined to the intestinal tract and produce no symptoms. How often
In a prospective investigation in the same unit, septicaemia complicated therapy in 13 of the 49 patients receiving parenteral hyperalimentation. In 8 of these, C. albicans was the causal organism. In several patients culture of the intravenous fluid was attempted
MOST
viræmia follows intestinal infection is not known for certain, but invasion of the central nervous system is rare. Paralysis results from perhaps one in every hundred infections with a virulent virus, and much less frequently with avirulent strains. Why is the central nervous system so seldom invaded ? The answer is not clear; but local irritation, such as that caused by some adjuvant-type vaccines, is believed to increase the susceptibility of the part of the spinal cord that supplies the infected area. Khalil and his colleagues’ have now shown that Egyptian children with poliomyelitis are more likely to show serological evidence of infection with Toxocara canis than the normal population-the prevalence of helminth infection in the two groups being 5-8% and 1-4%, respectively. This confirms the previous observations of Woodruff et a1. in Britain. There is not necessarily a direct relation between toxocara infection and poliomyelitis-the association may merely reflect similar standards of hygiene of those affected. Woodruff has suggested that toxocara larvm may act as vehicles, conveying additional amounts of virus from the lumen of the alimentary tract to the blood and through it to other tissues such as the central nervous system. It is also possible that the irritation resulting from intestinal infestation encourages invasion of the spinal cord in much the same way as adjuvant vaccines. 1.
2.
Khalil, H. M., Khattab, A. K., El-Fattah, S. M. A., Khalid, M. L., Awaad, S., Rifaat, M. A. Trans. R. Soc. trop. Med. Hyg. 1971, 65, 599. Woodruff, A. W., Bisseru, B., Dowe, J. C. Br. med. J. 1966, i, 1576.
the onset of fever, with negative results. The Minneapolis workers investigated the possibility that the glucose in the hyperalimentation fluid might have adversely affected the phagocytic powers of the hosts’ at
polymorphs, impairing their capacity to deal with the invading fungi. No evidence of this was found. Undoubtedly this dangerous complication of hyperalimentation also occurs in other hospitals. An inherent difficulty is that, by definition, parenteral hyperalimentation fluids are very nutritious; they contain high concentrations of glucose and are bound to support the growth of a wide variety of microorganisms, including pathogenic fungi. There is at present no safe method of preventing these infections. Antibacterial antibiotic ointments may be used the
infusion-sites, but would not control the fungus species. The Minneapolis workers do not seem to have tried antifungal antibiotic ointments, or prophylactic intravenous antifungal antibiotics. No doubt they thought that these would be too dangerous in patients already severely ill. Their findings highlight the need for aseptic methods of parenteral feeding. External arteriovenous shunts may be an at
answer.2,33 Curry, E. R., Quie, P. G. New Engl. J. Med. 1971, 285, 1221. Scribner, B. H., Cole, J. J., Christopher, T. G., Vizzo, J. E., Atkins, R. C., Blagg, C. R. J. Am. med. Ass. 1970, 212, 457. 3. Shils, M. E., Wright, W. L., Turnbull, A., et al. New Engl. J. Med. 1970, 283, 341.
1. 2.