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been gathered from a vast area over some 13 years. Twodistinct clinical syndromes were discernible, presumablyreflecting different portals of entry. Secondary infectionof superficial wounds or lacerations of the skin occurredin 15 instances; and so-called primary septicaemia in 24persons, 13 of whom died.

In the primary-septicxmia group, the illness beganabruptly with chills, fever, and then collapse, withoutany apparent foci of initial infection. The L+ vibrioin question was isolated by blood-culture from 20 of the24 patients. In many instances, ecchymoses, bullous

eruptions, or necrotic ulcers of the skin subsequently de-veloped, sometimes with other signs of blood-borne

spread. Despite intensive treatment, including antibi-otics such as penicillin, gentamicin, chloramphenicol,and tetracycline, 13 of these patients died. It is note-

worthy that all but 1 of the 24 patients either had ser-ious underlying disease, especially of the liver, or werealcoholics. In contrast, all but one of the wound infec-tions were in healthy people. Most of the cases, whethersepticxmic or septic, arose in summer, and the usual vic-tim was an elderly or middle-aged man. A somewhattenuous hypothesis is advanced for oysters, consumed

raw, as a likely source of infection in the patients withprimary septicaemia, though gastrointestinal upset wasuncommon. The natural habitat of L+ vibrios, by ana-logy with V. parahæmolyticus and V. alginolyticus, is

presumed to be the sea, but the actual incidence and dis-tribution are unknown. Although the American workerswere unable to calculate the risks to those eating sea-foods raw, they state that "patients with hepatic diseaseappear to be more susceptible than healthy persons toinfection with the L+ vibrio by the oral route". As tothe wound infections, they usually developed a day ortwo after a crab bite or exposure to sea-water; of the 15

patients, 1 with leukaemia died. There seems no way of

preventing these infections; but it does seem that somecases of "primary septicxmia" might be avoided if

people with liver disease ate their seafood well-cooked ornot at all.

ORAL IRON PREPARATIONS—DO WE NEEDTHEM ALL?

THERE are over forty oral iron preparations availableon prescription in the United Kingdom, varying fromsimple salts to complex formulations. Many owe theircontinuing success to the wide and erroneous belief thatelaborate formulations are less apt to cause gastrointes-tinal troubles. The side-effects are, in fact, much moredependent on the dose than on the nature of the prep-aration, and can be greatly reduced by prescription oflower doses2 and by getting the patient to take the medi-cine after food. Some iron intolerance also seems to havea psych6logical basis;3 so if the patient expects gastro-intestinal symptoms from iron, a word of explanationand reassurance from the doctor and dispensing phar-macist can be of great preventive value.

Iron-deficiency anaemia is common and there is a

temptation to correct it with large doses over a short

1. Drug Therapeut. Bull 1979, 17, 33.2. Crosby, W H. Archs intern. Med. 1978, 138, 616.3. Kerr, D. N. S , Davidson, L. S. P. Lancet, 1958, ii, 489.4. British National Formulary 1976-1978; p 157.

period. But, adverse effects apart, replacement of bodystores in an iron-deficient patient takes at least threemonths’ oral treatment of at least 100 mg elemental irona day after the haemoglobin deficit has been corrected,4and in most patients this can be achieved with twicedaily doses of ferrous sulphate 200 mg (60 mg Fe) or fer-rous fumarate taken after food. No advantage is offeredby preparations that contain trace amounts of othermetals such as copper or manganese. Furthermore, mostof the liquid and slow-release iron preparations are 2-10times more expensive with little, if any, evidence of

superiority. 1

SURGICAL TREATMENT OF CARPAL-TUNNELSYNDROME

Sir James Paget described the symptoms of carpal-tunnel compression in 1854, but it was nearly a centurybefore Sir James Learmonth did the first successful sur-gical operation to decompress the median nerve at thewrist. Nowadays this is one of the commonest oper-ations on the hand, but the result is not always perfect:from 1.2% to 25%6,7 of patients have residual symptomsof mild persistent numbness and continuing weakness inthe thumb. Precise diagnosis and careful operative tech-nique are essential for surgical relief of the pain andparæsthesiæ, which can be very unpleasant. Harris andothers8 survey the factors related to a successful out-come. In all their 124 cases the diagnosis was confirmedby nerve-conduction studies. Patients with motor-nervedelay had a more favourable result than those with onlysensory abnormalities. The preoperative duration ofsymptoms did not influence the surgical result. Classicsymptoms were sometimes present with normal nerveconduction times, and this is particularly true in the pa-tient with rheumatoid arthritis. Age did not affect theoutcome of operation. A common cause for surgical fail-ure is incomplete division of the volar carpal ligament.9This is most likely if the ligament is sectioned "blindly"through a small skin incision in the hope of producinga very small scar. The skin incision must be long enoughto display the whole length of the ligament. Another fac-tor predisposing to failure is tenosynovitis, either non-specific or associated with joint disease in the carpus.Synovectomy should be done if adequate decompressioncannot be obtained without removal of at least a portionof the synovium. The carpal tunnel should be inspectedfor possible occasional intrusions such as a ganglion, alipoma, or a large bony spur from an adjacent osteoarth-ritic joint. Harris et al.8 recommended neurolysis of themedian nerve when it is surrounded by thickened syno-vial tissue. The recurrent motor branch should be

decompressed when it passes through instead of aroundthe distal edge of the carpal ligament. Routine nerve-conduction tests are useful not only for indicating thedegree of nerve compression but also for providing abaseline for postoperative studies should recovery beslow.

’

5. Das, S. K., Brown, H. G. Hand, 1976, 8, 243.6. Hybbinette, C. H., Mannerfelt, L. Acta orthop. scand. 1975, 46, 610.7. Semple, J. C., Cargill, A. O. Lancet, 1969, i, 918.8. Harris, C., Tanner, E., Goldstein, M. N., Pethee, D. S. J. Bone Jt Surg.

1979, 61A, 93.9. Langloh, N. D., Linscheid, R. L. Clin. Orthop. 1972, 83, 41.