362 units. The highly infective ringworm lesions in domestic animals often show arthrospores in microscopic preparations (especially Microsporum canis infections y. 29 T. mentagrophytes infections provide the best support for the hypothesis because of their diversity and their uniquely wide epidemiological spectrum. However, support for the hypothesis is by no means limited to this

Methods and Devices DETECTION OF HEPATITIS-B SURFACE ANTIGEN IN BLOOD AND BLOOD PRODUCTS DRIED ON FILTER PAPER

organism. T. rubrum,3

T. concentricum,30 E. floccosum,31 and the yeast C. albicans4.5 produce experimental human skin infections only in the presence of occlusion, which suggests that they too require substances such as CO2 to form active infective units. Occlusion also enables T.

rubrum, usually classified

as

a

strictly human patho-

to cause experimental infections in lower animals.32 Like T. mentagrophytes, T. rubrum has a granular, sporulating morphological phase which is associated with increased virulence,33 and it can form arthrospores.24 These parallels with the hypothesised life-history and biological properties of T. mentagrophytes suggest that most if not all fungi which cause acute skin infections are similar in regard to the effects of occlusion and CO2 concentrations on their morphology, meta-

gen,"

bolism, and pathogenicity. POTENTIAL APPLICATIONS

postulated relations between occlusion of the skin, CO2 tensions, and infectivity of dermatophytes suggest ways in which ringworm infections might be prevented or controlled. Specifically, these are: (1) removal of occlusive materials from the skin; (2) application The

K. H. NOORI

H. FARZADEGAN

F. ALA Iranian National Blood

Transfusion Service,

Tehran

BLOOD-SAMPLES dried on a piece of filter paper have been used in various screening tests,I-3 but not for the detection of hepatitis-B surface antigen (HBsAg). This simple method has the following advantages: 1. Blood-samples may be obtained from newborn infants, children, anaemic patients, pregnant women, and other adults such as drug addicts or the aged, from whom it is difficult to obtain venous blood or who may refuse such a procedure. 2. Samples are dry, light, easy to post, and cannot be broken or

spilt.

,

3. Samples are easy to store; they take up little space, and remain stable for a long time. 4. The greater ease and economy of this procedure will be useful in large-scale population screening projects. Methods One drop on a

(>0.025 ml) of capillary whole blood was collected piece of filter paper (Whatman 4) from ten

circular

of substances to the skin which would interfere with the action of CO2 or would prevent its accumulation; and (3) development of clothing which would be non-occlusive when wet. The first approach has proven successful in at least one well-conducted trial,34 but its application is obviously limited. Prevention of infections by means of the second and third approaches has not yet been

attempted. Requests for reprints should be addressed to Editor, Letterman Army Institute of Research, San Francisco, California 94129, U.S.A. REFERENCES 1. 2.

Knight, A. G. J. invest. Derm. 1972, 59, 354. Reinhardt, J. H., Allen, A. M., Gunnison, D., Akers, W.

A. ibid.

1974, 63,

419. 3. Singh, G. Br. J. Derm. 1973, 89, 595. 4. Maibach, H. I., Kligman, A. M. Archs Derm. 1962, 85, 233. 5. Rebora, A., Marples, R. R., Kligman, A. M. ibid. 1973, 108, 69. 6. Fry, L., Almeyda, J., McMinn, R. Br. J. Derm. 1970, 82, 593. 7. Sulzberger, M. B., Witten, V. H. Archs Derm. 1961, 84, 1027. 8. Bothwell, J. W., Rovee, D. T. in Surgical Dressings and Wound Healing (edited by K. J. Harkiss); p. 78. London, 1971. 9. Rovee, D. T., Kurowsky, C. A., Labun, J., Downes, A. M. in Epidermal Wound Healing (edited by H. I. Maibach and D. T. Rovee); p. 159. Chicago, 1972. 10. Sulzberger, M. B., Griffin, T. B., Wiley, H. S. Dermatologica, 1967, 135, 414. 11. Stoughton, R. B. J. invest. Derm. 1964, 42, 228. 12. Marples, R. R., Kligman, A. M. in Epidermal Wound Healing (edited by H. I. Maibach and D. T. Rovee); p. 241. Chicago, 1972. 13. Leyden, J. J. Int. J. Derm. 1974, 13, 342. 14. Allen, A. M., Taplin, D. J. Am. med. Ass. 1973, 226, 864 15. Allen, A. M., Taplin, D. Proc. 3rd int. Conf. Mycoses (Scientific Publication P.A.H.O. no. 204) 1975, p. 215. 16. Allen, A. M., Reinhardt, J. H., Akers, W. A., Gunnison, D. Archs Derm.

1973, 108, 233. 17. Georg, L. K., Hand, E. A., Menges, R. A. J. invest. Derm. 1956, 27, 335. 18. King, R. D., Dillavou, C. L., Greenberg, J. H., Jeppsen, J. C., Jaeger, J. S. Can. J. Microbiol. 1976, 22, 1720. 19. Chin, B., Knight, S. G. J. gen. Microbiol. 1975, 16, 642.

Effect of storage-time (1, 3, 7, 14, and 30 days) and different elution volumes (1 and 10 ml) on results of R.I.A. (log mean c.p.m.) for HBsAg on positive capillary (and venous (---- ) blood dried on filter paper.

20. Moss, E.

S., McQuowan, A. L. Atlas of Medical Mycology, p. 195. Baltimore,

Maryland, 1962. Malten, K. E., Thiele, F. A. J. Br. J. Derm. 1973, 89, 565. King, R. D., Cunico, R. L., Maibach, H. I., Greenberg, J. H., West, M. L., Jeppsen, J. C. Acta derm.-vener., Stockh. (in the press). 23. Frame, G. W., Strauss, W. G., Maibach, H. I. J. invest. Derm. 1972, 59, 21. 22.

155. 24.

Marples, M. J. The Ecology of the Human

Skin. 1965. Georg, L. K. Ann. N.Y. Acad Sci. 1960, 89, 69. Harris, G. F. Proc. R. Soc. Med. 1962, 55, 562. Taplin, D. Personal communication. Georg, L. K. J. invest. Derm. 1954, 23, 123. Blakemore, J. C. Personal communication.

25. 26. 27. 28. 29. 30. Gonzalez-Ochoa,

p. 430. Springfield, Illinois,

A., Ricoy, E., Bravo-Becherelle, M. A. J. invest. Derm. 1964, 42, 55. 31. Sloper, J. C. ibid. 1955, 25, 21. 32. Mertz, P. M. Personal communication. 33. Wong, K. O., Chan, Y. F. Br. J. Derm. 1968, 80, 671. 34. Nickerson, W. J., Irving, L., Mehmert, H. E. Archs Derm. Syph. 1945, 52, 365.

363 RELATION BETWEEN R.I.A. RATIO UNITS AND RESULTS OF OTHER METHODS FOR DETECTING HBsAg IN BLOOD AND BLOOD COMPONENTS DRIED ON FILTER PAPER FOR 1, 7, AND 30 DAYS

Reviews of Books Recent Advances in Intensive Therapy

n

Ausria II, Abbott.

i

i

I

t Auscell, Abbott.

I

I

iI

I

I

I

I

I

w.B.c.=white blood-cells.

healthy carriers of HBsAg. Blood was also collected from these subjects by venepuncture and was subsequently processed to obtain packed red-cells, plasma, and platelets. A drop of each of these blood products and a known HBsAg-positive plasma Cohn fraction-ii sample was also put on filter papers. These samples were stored in small polyethylene tubes and left to stand for 1, 3, 7, 14, and 30 days at 4°C and 370C in order to simulate some of the various conditions encountered in field studies. After the drying period, 1, 5, or 10 ml of a 0.85% saline solution was added to the tube and the paper was left to soak for 30 min. This solution was checked for the presence of

HB,Ag by immunoelectro-osmophoresis (I.E.O.P.), haemagglutination inhibition (H.A.I.), reverse passive ha-magglutination (R.P.H.A.) by Abbot’s Auscell, and radioimmunoassay (R.I.A.) by Abbott’s Ausria ii methods. Results assays detected HBsAg in eluates from all dried even after a 30-day drying period at 37°C. The samples accompanying figure shows results for capillary and venous blood. Dilutions in 1 ml gave the most strongly positive results although even with dilutions up to 10 ml, HBsAg was always found. The best storage temperature was 4°C. There was a marginal reduction in counts per minute (R.I.A.) at 23 °C, and storage at 37°C gave still lower counts, although positive samples were readily identified. We were able to detect HBsAg in all tencapillary samples drawn from healthy carriers previously shown to have positive venous blood-samples by R.I.A. with ratio units (R.U.=c.p.m. [sample]/c.p.m. [mean of 7 negative controls]) ranging from 85 to 10 and 34 to 3 (very weak) after a drying period of 30 days on filter paper. R.I.A. and R.P.H.A. seem to be the best methods for detecting HBsAg detection on filter paper (see accompanyR.I.A.

ing table). Our evidence suggests that the filter-paper technique would have logistic and economic advantages in hepatitis-B surveillance programmes, and when used with detection methods such as R.I.A. or R.P.H.A. would not be associated with a loss of sensitivity or specificity. The original samples will further be analysed after they have been stored for up to a year.

Requests for reprints should be addressed to F.A., Iranian National Blood Transfusion Service, 138 Villa Avenue, Tehran, Iran. REFERENCES 1. Garrick, M.

D., Dembure, P., Guthrie, R. New Engl. J. Med. 1973, 288,

1265.

2. Guthrie, R., Susi, A. Pediatrics, 1963, 32, 338. 3. Thielmann, K., Moreira Aquino, A. Clinica chim. Acta, 1971, 35, 237.

Edited

by

stone.

1977.

I. McA. LEDINGHAM.

Edinburgh: Churchill Living-

Pp. 257./:10.

THIS book is not a comprehensive practical manual on intensive therapy but consists of papers, many of which are excellent reviews, written by specialists in different areas of intensive care. Most chapters are therefore aimed at those involved in research or for those wanting reviews. The use of abbreviations makes the book difficult to read and sometimes the meaning of an abbreviation is not readily apparent. Many of the chapters are written by specialists outside Britain where patient management may be different. For instance, the chapter on the management of massive gastrointestinal haemorrhage, does not mention the use of cimetidine. Some authors assume that experts will be readily available and fail to stress that some diagnostic procedures can be dangerous in inexperienced hands (e.g., selective angiography in gastrointestinal haemorrhage or pulmonary angiography for the diagnosis of pulmonary thromboembolism in the absence of bypass facilities). Chapters on pathogenesis of acute renal failure and gram-negative sepsis would interest the research-worker, and topics such as patient selection, prognostic indices, and mobile intensive care may be valuable for persons involved in administration. Chapters on practical patient management include acute pancreatitis, coagulation disorders, hepatic failure, and thromboembolism. Because of the diversity of topics covered, the book will probably be of greater value as a reference book than as a book to be read in its entirety.

Respiratory Distress Syndrome of Shock and Trauma Post-traumatic Respiratory Failure: Major Problems in Clinical Surgery, vol. XXI. F. W. BLAISDELL and F. R. LEWIS, SNR. Philadelphia and London: Saunders. 1977. Pp. 237. 12.50.

THIS book is written for general and orthopaedic surgeons and covers the syndrome of acute respiratory failure which may occur 24-48 hours after haemorrhagic shock, sepsis, or severe trauma. Although there is some dispute as to whether a single syndrome of "shock lung" exists, early recognition and treatment of post-traumatic respiratory failure has been associated with a considerable reduction in mortality. The opening chapter describes the apparent increase in frequency of respiratory failure in severely ill surgical patients and the initial poor prognosis. The next chapter on differential diagnosis is out of place and superficial; it comes before a clear and concise account of the natural history of clinical, radiological, and pathological changes in respiratory distress syndrome. The subsequent chapters discuss the aetiology of the rapidly progressive hypoxia, the decrease in lung compliance, and the radiological infiltration. The authors are biased towards a thromboembolic cause of the condition and deal briefly with other possible mechanisms; however each causal factor is well referenced so that the reader may assess the authors’ reasons for the bias. The bias towards a single aetiology with no discussion of the interrelation with other factors (such as neuronal or hormonal) mars this part of the book. The sections on general and respiratory management are sound but the indications for mechanical ventilation will be more helpful to anaesthetists than to surgeons; no simple guide is given on when to ventilate. The authors reason well and give good references for their preference for salt and blood administration rather than colloid, but admit that the latter may be beneficial under certain circumstances. The final chapter on overall management includes the treatment of intravascular coagulation, the use of steroids, possible sepsis, and parenteral feeding; these topics are useful reminders of the associated