Letters
to the
Editor
319
standard agar dilution techniques using chocolate agar plates. Inocula were standardized to 10’ cfu ml-’ using the method of Miles & Misra. The plates were examined after an overnight incubation at 37°C in air + 5% CO,. All the strains were sent to Colindale CPHL in London for serotyping. The findings are shown in Table I. Nose and throat swabs from 150 ward contacts (patients, doctors, nurses, cleaning staff) were taken and also screened for penicillin-resistant pneumococci. We detected no carriers. This report highlights the fact that penicillin-resistant pneumococci will probably become more common in the near future. Regional resistance rates may be higher or lower than the national figures. Hence all laboratories should be encouraged to record sensitivity to several antibiotics for use in their own areas so as to enable them to advise clinicians on appropriate antibiotics to use in empirical treatment of infection. If drug-resistant pneumococci become widespread the treatment of pneumococcal infection will need re-evaluation. Curiously there was no evidence of patient-to-patient transmission. J. Myint H. Panigrahi
North
Department Manchester
of Microbiology, General Hospital, Delaunays Road, Crumpsall, Manchester M8 6RB
References 1. Hansman D, Bullin MM. A resistant pneumococcus. Lancet 1967; 2: 264-265. 2. Jacobs MR, Koornhof HJ, Robins-Browne RM et al. Emergence of multiply resistance pneumococci. N Engl J Med 1978; 299: 735-740. 3. Casal J, Fen011 A, Vicioso MD, Munoz R. Increase in resistance to penicillin in pneumococci in Spain. Lancet 1989; 1: 735.
Sir, Ciprofloxacin-resistant Staphylococcus
methicillin-sensitive aureus
We read with interest the recent report in theJournal of Hospital Infection by Dyas & Seymour-Shove (16: 175-177) of an outbreak of ciprofloxacinresistant methicillin-sensitive Staphylococcus aweus on a geriatric ward. While we agree with their recommendation for routine monitoring of ciprofloxacin sensitivity in S. aureus, our own experience does not support their assertion that the role of ciprofloxacin in the treatment of staphylococcal infection would seem to be curtailed.
320
Letters
to the Editor
For the past 2 years ciprofloxacin has been used for the empirical treatment of patients presenting to the Renal Unit at St Thomas’ Hospital with peritonitis complicating continuous ambulatory peritoneal dialysis (CAPD). Ciprofloxacin has been given by the intraperitoneal route at a dose of 50 mg 1-l of dialysate fluid for 7’ or 5 days,’ or at half this dose for 5 days.3 To date, 22.5 episodes have been treated, with a success rate for all organisms, including staphylococci, equivalent to that achieved with standard regimens. Nineteen of these episodes were caused by S. aureus (all were methicillin sensitive), and none has been resistant to ciprofloxacin (MIC > 4-O mg 1-l). The mean MIC of these isolates was 0.6 mg 1-l with a range of 0.25-2.0 mg 1-l. We have previously reported the emergence of resistance to ciprofloxacin (MIC > 4.0 mg 1-l) amongst the organisms most commonly responsible for CAPD peritonitis, coagulase-negative staphylococci (CNS).4 However, the rate of recovery of ciprofloxacin-resistant CNS has not increased (85% over the past year), and ciprofloxacin retains its position as our first-line agent for the treatment of patients presenting with CAPD peritonitis. We have screened 52 CAPD patients for skin carriage of ciprofloxacin-resistant staphylococci one year after the introduction of ciprofloxacin.4 Carriage of resistant CNS has been detected in one-third of CAPD patients, but resistance has not been found amongst S. uureus. The majority of our CAPD patients are out-patients and receive treatment as such. Cross-infection is a rarity; CAPD peritonitis caused by all staphylococci usually results from auto-infection.5-7 Thus, the reservations of Dyas & Seymour-Shove, based on the observation of outbreaks of cross-infection amongst in-patients of hospital units where there has been a strong selective pressure, are not universally applicable. Such outbreaks have been described for a wide variety of organisms and antibiotics, many of which remain in common use. We feel that the available data does not justify the condemnation of ciprofloxacin for the treatment of staphylococcal infection. Two years after its introduction ciprofloxacin continues to be a valuable agent for the treatment of such infections in CAPD patients at St Thomas’ Hospital. M. S. Dryden
Department of Microbiology, UMDS, St. Thomas’ Hospital, London SE1 7EH *Department of Microbiology, St Bartholemew’s Hospital, London EClA 7BE
H. A. Ludlam* I. Phillips
References 1. Ludlam HA, Barton I, White ciprofloxacin for the treatment peritoneal dialysis. J Antimicrob
LL, McMullin C, King A, Phillips I. Intraperitoneal of peritonitis in patients receiving continuous ambulator) Chemother 1990; 25: 843-851.
to the
Editor
319
standard agar dilution techniques using chocolate agar plates. Inocula were standardized to 10’ cfu ml-’ using the method of Miles & Misra. The plates were examined after an overnight incubation at 37°C in air + 5% CO,. All the strains were sent to Colindale CPHL in London for serotyping. The findings are shown in Table I. Nose and throat swabs from 150 ward contacts (patients, doctors, nurses, cleaning staff) were taken and also screened for penicillin-resistant pneumococci. We detected no carriers. This report highlights the fact that penicillin-resistant pneumococci will probably become more common in the near future. Regional resistance rates may be higher or lower than the national figures. Hence all laboratories should be encouraged to record sensitivity to several antibiotics for use in their own areas so as to enable them to advise clinicians on appropriate antibiotics to use in empirical treatment of infection. If drug-resistant pneumococci become widespread the treatment of pneumococcal infection will need re-evaluation. Curiously there was no evidence of patient-to-patient transmission. J. Myint H. Panigrahi
North
Department Manchester
of Microbiology, General Hospital, Delaunays Road, Crumpsall, Manchester M8 6RB
References 1. Hansman D, Bullin MM. A resistant pneumococcus. Lancet 1967; 2: 264-265. 2. Jacobs MR, Koornhof HJ, Robins-Browne RM et al. Emergence of multiply resistance pneumococci. N Engl J Med 1978; 299: 735-740. 3. Casal J, Fen011 A, Vicioso MD, Munoz R. Increase in resistance to penicillin in pneumococci in Spain. Lancet 1989; 1: 735.
Sir, Ciprofloxacin-resistant Staphylococcus
methicillin-sensitive aureus
We read with interest the recent report in theJournal of Hospital Infection by Dyas & Seymour-Shove (16: 175-177) of an outbreak of ciprofloxacinresistant methicillin-sensitive Staphylococcus aweus on a geriatric ward. While we agree with their recommendation for routine monitoring of ciprofloxacin sensitivity in S. aureus, our own experience does not support their assertion that the role of ciprofloxacin in the treatment of staphylococcal infection would seem to be curtailed.
320
Letters
to the Editor
For the past 2 years ciprofloxacin has been used for the empirical treatment of patients presenting to the Renal Unit at St Thomas’ Hospital with peritonitis complicating continuous ambulatory peritoneal dialysis (CAPD). Ciprofloxacin has been given by the intraperitoneal route at a dose of 50 mg 1-l of dialysate fluid for 7’ or 5 days,’ or at half this dose for 5 days.3 To date, 22.5 episodes have been treated, with a success rate for all organisms, including staphylococci, equivalent to that achieved with standard regimens. Nineteen of these episodes were caused by S. aureus (all were methicillin sensitive), and none has been resistant to ciprofloxacin (MIC > 4-O mg 1-l). The mean MIC of these isolates was 0.6 mg 1-l with a range of 0.25-2.0 mg 1-l. We have previously reported the emergence of resistance to ciprofloxacin (MIC > 4.0 mg 1-l) amongst the organisms most commonly responsible for CAPD peritonitis, coagulase-negative staphylococci (CNS).4 However, the rate of recovery of ciprofloxacin-resistant CNS has not increased (85% over the past year), and ciprofloxacin retains its position as our first-line agent for the treatment of patients presenting with CAPD peritonitis. We have screened 52 CAPD patients for skin carriage of ciprofloxacin-resistant staphylococci one year after the introduction of ciprofloxacin.4 Carriage of resistant CNS has been detected in one-third of CAPD patients, but resistance has not been found amongst S. uureus. The majority of our CAPD patients are out-patients and receive treatment as such. Cross-infection is a rarity; CAPD peritonitis caused by all staphylococci usually results from auto-infection.5-7 Thus, the reservations of Dyas & Seymour-Shove, based on the observation of outbreaks of cross-infection amongst in-patients of hospital units where there has been a strong selective pressure, are not universally applicable. Such outbreaks have been described for a wide variety of organisms and antibiotics, many of which remain in common use. We feel that the available data does not justify the condemnation of ciprofloxacin for the treatment of staphylococcal infection. Two years after its introduction ciprofloxacin continues to be a valuable agent for the treatment of such infections in CAPD patients at St Thomas’ Hospital. M. S. Dryden
Department of Microbiology, UMDS, St. Thomas’ Hospital, London SE1 7EH *Department of Microbiology, St Bartholemew’s Hospital, London EClA 7BE
H. A. Ludlam* I. Phillips
References 1. Ludlam HA, Barton I, White ciprofloxacin for the treatment peritoneal dialysis. J Antimicrob
LL, McMullin C, King A, Phillips I. Intraperitoneal of peritonitis in patients receiving continuous ambulator) Chemother 1990; 25: 843-851.
