the Editor

AMPICILLIN-RESISTANT HÆMOPHILUS INFLUENZÆ IN OTITIS MEDIA SIR,-Since the letter of Thomas et al.l on ampicillinresistant Hamophilus influenzce at least 40 such strains have

reported. Most of them seem to be capsulated and produce i-lactamase.2 It has been pointed out that acute


otitis media is


of the most


infections caused

by H. influenza and that the

appearance of resistant strains reflect the intensive use of ampicillin in this disease.3 We want to report 3 cases of H. influenza otitis which

support this view. The patients suffered from repeated episodes of otitis media and were first treated with penicillin V. Later they received ampicillin or azidocillin in several courses before the isolation of the resistant H. influenzce strains. In 1 case H. infiuenzae sensitive to azidocillin was isolated from the middle-ear exudate on the same day azidocillin treatment started. Seven days later, while still under therapy, ear exudate yielded resistant H. influenza. In the 2nd case culture before ampicillin therapy yielded H. influenzce sensitive to ampicillin in ear exudate. Five days after treatment was discontinued, resistant H. influenzce were found in ear exudate and a mixture of sensitive and resistant bacteria in the nasopharynx. In the 3rd case resistant bacteria were found in ear exudate on the third day of ampicillin therapy. No culture was obtained

prior to therapy. All strains were non-capsulated and produced 0-lactamase. Using the agar-plate dilution technique and an inoculate of about 10° bacteria the minimum inhibitory concentrations exceeded 80 :jLg. per ml. of ampicillin, penicillin G, penicillin V, and azidocillin.

In at least 2 of the 3 cases ampicillin or azidocillin therapy caused a selection in vivo of resistant H. influenzce in a sensitive bacterial population. This has to our knowledge not been reported in treatment with penicillin V since this drug was introduced about twenty years ago. Further, repeated treatment of relapsing otitis media or other respiratory-tract infections, in which the strain has a pronounced ability to persist in the patient, seems to increase the possibility for the selection of resistant H. tM/hMKjM strains more than the high-dose treatment of meningitis or epiglottitis given over a short period of time. Therefore, it may be justified to modify the widespread opinion that ampicillin and azidocillin are the drugs of choice in treatment of several respiratory-tract infections and to restrict the use of these drugs. Departments of E.N.T., Infectious Diseases, and Medical Microbiology, University Hospital, S-221 85, Lund, Sweden.

3970: part 1: 1966 (amended Aug. 28, 1969), a pass in the Bowie and Dick test, in conjunction with the signal " sterile " at the end of the run, indicates the absence of significant amounts of air in the sterilising chamber, complete penetration of the challenge pack by steam within the selected temperature range, and a sterilising holding period of appropriate duration. Maintenance of some sterilisers is substandard and automatic control systems may become defective, thus leading to a Bowie and Dick test fail. However, the test sheet showing a pass will not by itself indicate the erroneous use of temperatures in the range 121--2-0° C instead of 134—4—0° C, or a holding time at temperature for 3 minutes instead of 15 minutes. A time/temperature record chart sensing from the drain and/or simulator for the run attached to the test sheet would of course reveal the error, but these recorders are not mandatory in the British Standard; further, a fault may develop in the recorder system such as a small leak at the simulator. Those responsible for sterile supply may therefore desire reassurance in addition to that given by time/temperature charts together with the Bowie and Dick test. They may, for instance, desire to have direct confirmatory evidence of exactly how long the centre of the standard challenge pack was at sterilising temperature. We have therefore carried out trials with the standard pack, thermocouple charts, 3M 1222 tape, and Vac and Diack tubes. Vac pellets start to melt at 132° C. Using the recognised British temperature/time relationship 134—4—0° C for 3 minutes, complete melting of the pellet definitely indicates the attainment of a temperature within the desired range, but complete melting occurs so long before the end of the necessary holding time to render the device valueless as an indicator of time at temperature. Similarly, Diack pellets start to melt at 121° C but are valueless as indicators of the required 15 minutes at temperature 121-i-2-0° C. We are at present working with test papers surface impregnated with inks whose change in colour indicates clearly exposure to steam at 134-f-4-0° C related to time of exposure and a warning of excessive exposure time. The inked papers are small enough to be stuck on to the Bowie and Dick test sheet near the centre, but not overlying the



SIR,-Robert F. Smith (June 29, p. 1349) and Reid and Dixon (Jan. 11, p. 104) support the advice given by the New Zealand Department of Health in 1970 about the use of Smith and Underwood Diack ’ and Vac ’ fusible pellets in conjunction with other indicators such as the 3M tape within the standard challenge pack. In properly maintained high pre-vacuum sterilisers designed to, at least, conform with British Standard 1. Thomas, W. J., McReynolds, J. W., Mock, C. R., Baily, D. W. Lancet, 1974, ii, 313. 2. Khan, W., Ross, S., Rodriguez, W., Controni, G., Saz, A. K. J. Am. med. Ass. 1974, 229, 298. 3. Controni, G., Rodriguez, W., Pumphrey, R., Ross, S., Deane, C., Khan, W. Lancet, 1974, ii, 1398.

test cross. Lothian Health Board, 11

Drumsheugh Gardens, Edinburgh EH3 7QQ. Theatre Service Centre, Royal Infirmary of Edinburgh. Central Sterilising Department, Royal Infirmary of Edinburgh.



SIR,-Dr Richards and others (April 5, p. 812) reiterate the question of whether osteitis condensans ilii (o.c.i.) " is a fortuitous radiological finding in some patients with back pain and fibrositis or whether it is a cause of these symptoms ". The radiologist is obviously not the one to answer that clinical question. He might, however, be able to establish a clue to activity by doing isotopic bone-scans on all such patients, as Richards et al. have already done on 5 female patients with O.C.l., in whom the bone-scans were normal. Condensation of bone is the hallmark of ischsemia, demineralisation is the hallmark of hyperamiia. It comes as no surprise that there is an increased uptake in ankylosing spondylitis. One should expect a decreased uptake in O.C.l. if the condition has stabilised. I have been able in one case to observe the appearance of o.c.i. after pregnancy in a young woman whose sacroiliac joints had been normal a few years earlier. Such retrospective studies would also be helpful.

Letter: Ampicillin-resistant Haemophilus influenzae in otitis media.

1135 Letters to the Editor AMPICILLIN-RESISTANT HÆMOPHILUS INFLUENZÆ IN OTITIS MEDIA SIR,-Since the letter of Thomas et al.l on ampici...
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