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CYTODIAGNOSIS OF VIRAL ENCEPHALITIS
609 before
conduction
in
the
cord
becomes
severely
compromised. It is fortunate that this patient did not have a lumbar which is often used in the management of
epidural block,
labour in this hospital. Had she been given epidural analgesia the development of the abscess would have been attributed to the procedure. This has obvious medicolegal implications. The incidence of infective complications of epidural analgesia must be very low. In a review of 32,000 cases of epidural analgesia by both the lumbar and caudal routes in the world literature Dawkins 2 was unable to find even one case of epidural abscess. None the less, perhaps we should consider any general illness causing a possible diminished resistance to infection and pyogenic skin lesions anywhere on the body as contraindications to the
procedure. We should like to thank Mr A. B. for permission to report this case. Southmead
Hospital, Westbury-on-Trym, Bristol BS10 5NB.
Byles
and Mr D. G.
Phillips
C. G. MALE ROGER MARTIN.
DIAGNOSIS OF DEEP VENOUS THROMBOSIS
SIR,-In reviewing the literature on radioactivefibrinogen diagnosis of deep venous thrombosis, I found results relating to hernias, strokes, &c., but not controls. I realise in most studies the contralateral leg has been used " a control " and the venographic evidence appears incontrovertible, but the fact remains no-one appears to have studied controls (fit people). It is just conceivable that a significant number of the normal population if investigated by this technique might also have clinically silent D.v.T.s. It seems crucial to any argument regarding the natural history, prophylaxis, and treatment of this condition to have such information. I would, therefore, be most grateful if anyone could furnish me with details of any truly controlled studies of which they have knowledge. as
Faculty of Medicine, Surgical Division, 40 Fanshawe Street, Southampton SO9 4PE.
A. D. B. CHANT.
CYTODIAGNOSIS OF VIRAL ENCEPHALITIS
SlR,—Iread with interest the two reports by Dr Dayan and Miss Stokes (Jan. 27, p. 177) and by Dr Longson and others (Feb. 17, p. 371) about the early diagnosis of viral encephalitis with special reference to herpetic infection. I wish to draw attention to a paper3 by me and my colleagues about the use of cytology in the diagnosis of viral Atypical lymphoid central-nervous-system infections. cells have been recognised in the spinal fluid of patients with viral infections. It is not surprising that actual viral inclusions were observed by us in 2 patients who had evidence of viral encephalitis clinically, electroencephalographically, on brain biopsy, and in brain-biopsy viral cultures. I think
no
one test
should be used
to
establish the
diagnosis of a condition like viral encephalitis. Brain biopsy, although diagnostic and ideal, has its limitations. On the other hand, immunofluorescent examination of the cerebrospinal fluid is highly specific. A clinical picture, electroencephalographic findings, and immunofluorescent and cytological studies on the cerebro2. 3. 4.
Dawkins, C. S. M. Anœsthesia, 1969, 24, 554. Gupta, P. K., Gupta, P. C., Roy, S., Banerji, A. K. Acta cytol. 1972, 16, 563. Spriggs, A. I., Boddington, M. M. The Cytology of Effusions. London, 1968.
spinal fluid, if all corroborative, should be considered adequate for institution of specific therapy. Firm diagnosis -how firm ? Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, U.S.A.
PRABODH K. GUPTA.
IS LIPOPROTEIN ESTIMATION REALLY
NECESSARY ?
SIR,-Fredrickson’s classification1 of " lipoproteinsemias" represented a milestone in the description of derangements in lipid metabolism. The limitations of this classification were recognised by Fredrickson et al. and were subsequently emphasised in a report by W.H.O.2 Recent reviews 3,4 have highlighted the complex nature of lipoprotein metabolism and hinted at shortcomings 4 in Fredrickson’s classification, which is, nevertheless, widely used.5-10 With regard to therapy Levy8 stated: " Perhaps the greatest advantage of the typing system, however, lies in pharmacologic and dietary evaluation, and in the extension of the results of these studies to the practical management of the affected patient." This contention is at variance with the observations of Bricker,l1 whose therapeutic regimens for his hyperlipidasmic classes (based on triglyceride and cholesterol measurements) did not differ significantly from those used in the type-specified hyper-
lipoproteinaemias. e-lo One of the prime considerations in extending studies on plasma-lipoproteins has been the observed relationship between ischaemic heart-disease and plasma-lipids.s-7,lo It is evident from the findings of the Framingham study,12 however, that lipoproteins provide no better correlates with ischxmic heart-disease than
measurements of cholesterol or triglycerides. With regard to triglyceride metabolism, alterations in plasma-lipoprotein concentrations are secondary to changes in triglyceride output induced by drugs, disease, or diet.13 There is no evidence that hepatic triglyceride secretion or plasma transport is ever rate-limited by availability of apoprotein. Preoccupation with lipoprotein analysis and typing tends to obscure the fundamental feature of the primary lipid disturbance-that involving the triglycerides. Similar arguments may be applied to cholesterol metabolism. Alaupovic et al.14 have suggested a classification of lipoprotein abnormalities on the basis of the apoproteins-which are immunochemically definable, and which probably represent " the unique components and sole determinants of the chemical characteristics, and possibly metabolic functions of the corresponding lipoproteins ". This represents a rational approach as it focuses on the protein moiety, which, as with the individual lipids, may be subject 1. 2. 3. 4. 5. 6. 7. 8.
9. 10. 11. 12. 13. 14.
Fredrickson, D. S., Levy, R. I., Lees, R. S. New Engl. J. Med. 1967, 276, 34, 94, 148, 215, 273. Bull. Wld Hlth Org. 1970, 43, 89. Scanu, A., Wisdom, C. A. Rev. Biochem. 1972, 41, 703. Lewis, B. in Scientific Basis of Medicine: Annual Reviews (edited by I. Gilliland and J. Francis). London, 1972. Lancet, 1971, ii, 801. Lehmann, H., Lines, J. G. ibid. 1972, i, 557. Brock, J. F., Watermeyer, G. S. Afr. med. J. 1972, 46, 1958. Levy, R. I. in Lipids and Heart Disease (edited by F. Hoffman); p. 69. Amsterdam, 1968. Bagdade, J. D., Bierman, E. L. Med. Clin. N. Am. 1970, 54, 1383. Strisower, E. H., Adamson, G., Strisower, B. ibid. p. 1599. Bricker, L. A. ibid. 1971, 55, 403. Kannel, W. J. Am. J. clin. Nutr. 1971, 24, 1074. Robinson, D. S. in Comprehensive Biochemistry (edited by M. Florkin and E. H. Stotz); vol. XVIII. Amsterdam, 1970. Alaupovic, P., Lee, D. M., McConathy, W. J. Biochim. biophys. Acta, 1972, 260, 689.
conduction
in
the
cord
becomes
severely
compromised. It is fortunate that this patient did not have a lumbar which is often used in the management of
epidural block,
labour in this hospital. Had she been given epidural analgesia the development of the abscess would have been attributed to the procedure. This has obvious medicolegal implications. The incidence of infective complications of epidural analgesia must be very low. In a review of 32,000 cases of epidural analgesia by both the lumbar and caudal routes in the world literature Dawkins 2 was unable to find even one case of epidural abscess. None the less, perhaps we should consider any general illness causing a possible diminished resistance to infection and pyogenic skin lesions anywhere on the body as contraindications to the
procedure. We should like to thank Mr A. B. for permission to report this case. Southmead
Hospital, Westbury-on-Trym, Bristol BS10 5NB.
Byles
and Mr D. G.
Phillips
C. G. MALE ROGER MARTIN.
DIAGNOSIS OF DEEP VENOUS THROMBOSIS
SIR,-In reviewing the literature on radioactivefibrinogen diagnosis of deep venous thrombosis, I found results relating to hernias, strokes, &c., but not controls. I realise in most studies the contralateral leg has been used " a control " and the venographic evidence appears incontrovertible, but the fact remains no-one appears to have studied controls (fit people). It is just conceivable that a significant number of the normal population if investigated by this technique might also have clinically silent D.v.T.s. It seems crucial to any argument regarding the natural history, prophylaxis, and treatment of this condition to have such information. I would, therefore, be most grateful if anyone could furnish me with details of any truly controlled studies of which they have knowledge. as
Faculty of Medicine, Surgical Division, 40 Fanshawe Street, Southampton SO9 4PE.
A. D. B. CHANT.
CYTODIAGNOSIS OF VIRAL ENCEPHALITIS
SlR,—Iread with interest the two reports by Dr Dayan and Miss Stokes (Jan. 27, p. 177) and by Dr Longson and others (Feb. 17, p. 371) about the early diagnosis of viral encephalitis with special reference to herpetic infection. I wish to draw attention to a paper3 by me and my colleagues about the use of cytology in the diagnosis of viral Atypical lymphoid central-nervous-system infections. cells have been recognised in the spinal fluid of patients with viral infections. It is not surprising that actual viral inclusions were observed by us in 2 patients who had evidence of viral encephalitis clinically, electroencephalographically, on brain biopsy, and in brain-biopsy viral cultures. I think
no
one test
should be used
to
establish the
diagnosis of a condition like viral encephalitis. Brain biopsy, although diagnostic and ideal, has its limitations. On the other hand, immunofluorescent examination of the cerebrospinal fluid is highly specific. A clinical picture, electroencephalographic findings, and immunofluorescent and cytological studies on the cerebro2. 3. 4.
Dawkins, C. S. M. Anœsthesia, 1969, 24, 554. Gupta, P. K., Gupta, P. C., Roy, S., Banerji, A. K. Acta cytol. 1972, 16, 563. Spriggs, A. I., Boddington, M. M. The Cytology of Effusions. London, 1968.
spinal fluid, if all corroborative, should be considered adequate for institution of specific therapy. Firm diagnosis -how firm ? Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, U.S.A.
PRABODH K. GUPTA.
IS LIPOPROTEIN ESTIMATION REALLY
NECESSARY ?
SIR,-Fredrickson’s classification1 of " lipoproteinsemias" represented a milestone in the description of derangements in lipid metabolism. The limitations of this classification were recognised by Fredrickson et al. and were subsequently emphasised in a report by W.H.O.2 Recent reviews 3,4 have highlighted the complex nature of lipoprotein metabolism and hinted at shortcomings 4 in Fredrickson’s classification, which is, nevertheless, widely used.5-10 With regard to therapy Levy8 stated: " Perhaps the greatest advantage of the typing system, however, lies in pharmacologic and dietary evaluation, and in the extension of the results of these studies to the practical management of the affected patient." This contention is at variance with the observations of Bricker,l1 whose therapeutic regimens for his hyperlipidasmic classes (based on triglyceride and cholesterol measurements) did not differ significantly from those used in the type-specified hyper-
lipoproteinaemias. e-lo One of the prime considerations in extending studies on plasma-lipoproteins has been the observed relationship between ischaemic heart-disease and plasma-lipids.s-7,lo It is evident from the findings of the Framingham study,12 however, that lipoproteins provide no better correlates with ischxmic heart-disease than
measurements of cholesterol or triglycerides. With regard to triglyceride metabolism, alterations in plasma-lipoprotein concentrations are secondary to changes in triglyceride output induced by drugs, disease, or diet.13 There is no evidence that hepatic triglyceride secretion or plasma transport is ever rate-limited by availability of apoprotein. Preoccupation with lipoprotein analysis and typing tends to obscure the fundamental feature of the primary lipid disturbance-that involving the triglycerides. Similar arguments may be applied to cholesterol metabolism. Alaupovic et al.14 have suggested a classification of lipoprotein abnormalities on the basis of the apoproteins-which are immunochemically definable, and which probably represent " the unique components and sole determinants of the chemical characteristics, and possibly metabolic functions of the corresponding lipoproteins ". This represents a rational approach as it focuses on the protein moiety, which, as with the individual lipids, may be subject 1. 2. 3. 4. 5. 6. 7. 8.
9. 10. 11. 12. 13. 14.
Fredrickson, D. S., Levy, R. I., Lees, R. S. New Engl. J. Med. 1967, 276, 34, 94, 148, 215, 273. Bull. Wld Hlth Org. 1970, 43, 89. Scanu, A., Wisdom, C. A. Rev. Biochem. 1972, 41, 703. Lewis, B. in Scientific Basis of Medicine: Annual Reviews (edited by I. Gilliland and J. Francis). London, 1972. Lancet, 1971, ii, 801. Lehmann, H., Lines, J. G. ibid. 1972, i, 557. Brock, J. F., Watermeyer, G. S. Afr. med. J. 1972, 46, 1958. Levy, R. I. in Lipids and Heart Disease (edited by F. Hoffman); p. 69. Amsterdam, 1968. Bagdade, J. D., Bierman, E. L. Med. Clin. N. Am. 1970, 54, 1383. Strisower, E. H., Adamson, G., Strisower, B. ibid. p. 1599. Bricker, L. A. ibid. 1971, 55, 403. Kannel, W. J. Am. J. clin. Nutr. 1971, 24, 1074. Robinson, D. S. in Comprehensive Biochemistry (edited by M. Florkin and E. H. Stotz); vol. XVIII. Amsterdam, 1970. Alaupovic, P., Lee, D. M., McConathy, W. J. Biochim. biophys. Acta, 1972, 260, 689.