Postgrad Med J: first published as 10.1136/pgmj.53.618.216 on 1 April 1977. Downloaded from Postgraduate Medical Journal (April 1977) 53, 216-218

Streptococcus agalactiae in urinary tract F. S. MHALU M.B., Ch.B., Dip. Bact. Department ofBacteriology, Royal Postgraduate Medical School, Hammersmith Hospital, London W12

Summary for all the isolates because no quantitative bacterio- agalactiae was found to be the cause logical data had been provided. Other reports of of approximately 1% of urinary tract infections in a group B streptococci in urinary tract infections London teaching hospital in the 2 years studied. include those by Feingold, Stagg and Kunz (1966), Of the forty-eight patients with this , forty- Anthony and Concepcion (1975) and Mhalu (1976) three were female. In nine patients the infection but to date, details of the types of patients with followed renal transplantation while in nine others it urinary infections with this organism have not been occurred in the presence of chronic renal failure. The documented. The reported high prevalence of group rest, who included seven females who developed the B streptococci in the urethra especially in those with infection following hysterectomies, had other clinical sexually transmitted diseases encouraged investiga- conditions which could have predisposed to such tion into the frequency with which they cause urinary infections. The rarity of by tract infections and the types of patient involved. S. agalactiae is in contrast to the high frequency with which the colonizes the normal urethra. Materials and methods

organism by copyright. III and II were the predominant isolates in In the period between July 1974 and June 1976, a these patients with urinary tract infections; this record was kept of all significant isolations of group corresponds to the distribution of the different sero- B streptococci from urine. The age, sex and contri- types in the genito-urinary tract of normal indivi- butory clinical condition of each patient were noted. duals. These were compared with a 10% random sample of all patients, seen in this hospital in 1975, with Introduction urinary tract infection due to organisms other than Streptococcus agalactiae (Lancefield's group B group B streptococci. The criteria used for urinary Streptccoccus) constitutes part of the normal tract infection were a bacterial of more

pure growth http://pmj.bmj.com/ bacterial flora of the human lower genito-urinary than 105 colony-forming units/ml of freshly voided tract. Carriage rates in this site vary according to midstream urine together with pyuria. The latter was methods of detection used but values up to 36% defined as more than five pus cells per high power have been reported from the more recent investiga- field on microscopy of the centrifuged deposit from tions (Christensen et al., 1976; Finch, French and 10 ml of urine resuspended in 0-5 ml. Culture was Phillips, 1976). Although venereal transmission of by streaking a 1/300 ml loopful of well mixed urine the organism has been suggested, there is no evidence on a MacConkey agar; a growth of 300 colonies to support its role as a cause of primary genital or more represented more than 105 organisms/mi. on September 25, 2021 by guest. Protected pathology (Wallin and Forsgren, 1975). Primary sensitivity tests with 25 ,ug; The major risk attaching to group B streptococci trimethoprim 1-25 ,tg; sulphafurazole 500 ,Ig and in the genital tract lies in their association with neo- nalidixic acid 30 ,ug or 200 jXg discs natal septicaemia and (Baker and Barrett, were done using the Stokes method (Stokes and 1973; Yow, 1974). Little work has been done on Waterworth, 1972) whenever pus cells or organisms their relationship to urinary tract infections. Eickhoff were evident in large numbers on microscopy. et al. (1964) reported three female patients with Throat and vaginal swabs were obtained from some acute pyelonephritis from two of whom 105 colony- of the patients for culture for group B streptococci. forming units of the organism/ml of urine were The streptococci were identified as belonging to isolated. The third was diagnosed by of the Lancefield's group B using the antigen extraction organism from blood culture. Wilkinson, Facklam method of Rantz and Randall (1955). Serotyping of and Wortham (1973) reported on 107 reference isolates from thirty-two of the patients was done at strains of group B streptococci from urinary tract the Streptococcus Reference Laboratory, Central infections but could not confirm an aetiological role Public Health Laboratory, Colindale, London. Postgrad Med J: first published as 10.1136/pgmj.53.618.216 on 1 April 1977. Downloaded from Streptococcus agalactiae in urinary tract infections 217 Results TABLE 2. Associated clinical conditions of a 10% random During the 2-year period, seventy-five isolates of sample of patients with urinary tract infections due to significant growth of S. agalactiae were obtained organisms other than S. agalactiae in 1975 from forty-eight patients with urinary tract infections. Sex This accounted for a 1% overall incidence of the group B Streptococcus in urinary tract infection. Clinical condition Female Male Total One patient had the organism isolated in significant Disease not directly related to numbers on separate occasions over a urinary tract pathology, e.g. eight period malignancies and congestive of4 months. Another had it isolated on four separate cardiac failure 13 8 21 occasions in 1 year. It was possible to get more than Urethral catheter in situ 8 4 12 one urine specimen from twenty-one of the patients Trauma to pelvis (including before antibacterial treatment was instituted and surgery to hip) 8 3 11 of B were Recurrent urinary tract infection 10 1 11 significant isolates group streptococci Normal young females (sexually confirmed in all of them. All but five of the patients active age) 9 - 9 were adult females varying in age between 19 and Pregnancy 7 7 81 years. The rest were males including a pre- No other condition 6 1 7 neonate whose was Post-hysterectomy 6 - 6 maturely born mother's vagina Malignancy of a pelvic organ colonized by group B Streptococcus. The primary (including urinary bladder) 1 4 5 clinical conditions of the forty-eight patients sub- Urine retention without to have tract infection with indwelling catheter 2 3 5 sequently proved urinary Ureteric obstruction 3 1 4 S. agalactiae are shown in Table 1, while the clinical Diabetes mellitus 4 - 4 conditions of those with urinary tract infection due Haematuria 2 1 3 to other organisms are shown in Table 2. Urinary incontinence 1 1 2 All the isolates grew optimally on MacConkey Chronic renal failure 2 2 with colonies in most cases. Occasional Puerperal pyrexia 1 1 agar pale pink Post-renal transplant 1 - 1 isolates gave obvious pink lactose fermenting colonies Cystic kidneys 1 1 by copyright. but these were easily distinguishable from the small Total 83 29 112 magenta colonies typical of S. faecalis. S. agalactiae could further be distinguished from S. faecalis on TABLE 3. Serotypes of S. agalac- the primary sensitivity plates by being fully sensitive tiae from patients with urinary to sulphafurazole while S. faecaiis is invariably tract infections resistant. All the isolates were sensitive to (ampicillin) and trimethoprim but, as expected, none No. of was sensitive to nalidixic acid. The few strains which Serotypes patients III 8 TABLE 1. Associated clinical conditions of patients with II 5 http://pmj.bmj.com/ urinary tract infections due to S. agalactiae Ia 4 Ib 4 Sex Ic 2 R 2 Clinical condition Female Male Total X 2 Post-renal transplant 8 1 9 II/III 1 Chronic renal failure 8 1 9 Non-typable 4 7 - 7 Total 32 Post-hysterectomy on September 25, 2021 by guest. Protected Pregnancy 4 - 4 Cystic kidneys 3 1 4 Normal young women (sexually were tested against nitrofurantoin proved sensitive active age) 3 - 3 to it. Of the five female patients who had high Disease not directly related to swabs taken in addition to urine urinary tract pathology, e.g. vaginal culture, congestive cardiac failure 3 - 3 four had identical S. agalactiae isolates. One patient Ureteric obstruction 2 - 2 who had urinary tract infection due to the Strepto- Recurrent urinary tract infection 1 - 1 1 month before labour, had identical strains Fracture of femur in elderly of the isolated from her throat and woman I - 1 organism vaginal Puerperal pyrexia 1 1 swabs and from various sites on her otherwise Diabetes mellitus 1 - 1 normal newborn infant. Post-transurethral prostatectomy - 1 1 Serotyping results shown in Table 3 indicated that Hypertension with hemiplegia 1 - type III constituted the majority of the isolates, Prematurity 1 1 followed by type II. The different serotypes were Total 43 5 48 widely distributed among the clinical conditions and Postgrad Med J: first published as 10.1136/pgmj.53.618.216 on 1 April 1977. Downloaded from 218 F. S. Mhalu within the various units where these patients were made and the opinions expressed are not necessarily those of nursed so that cross infection was the WHO. unlikely. I am grateful to Dr J. H. Darrell for advice and to Dr M. T. Parker for agreeing to have the strains Discussion serotyped. From the results, it is evident that despite its high in the S. is a rare References prevalence urethra, agalactiae ANTHONY, B.F. & CONCEPCION, N.F. (1975) Group B cause of urinary tract infection. Whereas coloniza- Streptococcus in a general hospital. Journal of Infectious tion rates are highest in the urethra of individuals Diseases, 132, 561. presenting with sexually-transmitted diseases (Chris- BAKER, C.J. & BARRETT, F.F. (1973) Transmission of group tensen et al., Wallin and B streptococci among parturient women and their neo- 1974; Forsgren, 1975), nates. Journal of Pediatrics, 83, 919. urinary tract infection by the organism occurs CHRISTENSEN, K.K., CHRISTENSEN, P., FLAMHOLC, L. & mostly in those with structural abnormalities in RIPA, T. (1974) Frequencies of streptococci of groups A, the urinary tract especially if associated with im- B, C, D and G in urethra and cervix swab specimens from deficiencies. Renal and patients with suspected gonococcal infection. Acta patho- munological transplantation logica et microbiologica scandinavica, Section B, 82, 470. chronic renal failure were the only significant CHRISTENSEN, K.K., RIPA, T., AGRUP, G. & CHRISTENSEN, P. predisposing clinical conditions to urinary tract (1976) Group B streptococci in human urethral and infection with S. agalactiae as compared to pre- cervical specimens. Scandinavian Journal of Infectious conditions to tract infection with Diseases, 8, 75. disposing urinary EICKHOFF, T.C., KLEIN, J.O., DALY, A.K., INGALL, D. & other organisms (P<0001 in each case). FINLAND, M. (1964) Neonatal and other infections Some of the patients had recurrence of infection due to group B beta-hemolytic streptococci. New England even after adequate therapy with appropriate agents Journal of Medicine, 271, 1221. and co-trimoxazole to which all FEINGOLD, D.S., STAGG, N.I. & KUNZ, L.J. (1966) Extra including ampicillin respiratory steptococcal infections. Importance of the the isolates were fully sensitive. Recurrence may have various serologic groups. New England Journal ofMedicine, been due to inadequate eradication of the organism 275, 356. from the reservoir of infection which includes the FINCH, R.G., FRENCH, G.L. & PHILLIPS, I. (1976) Group B and faeces. The streptococci in the female genital tact. British Medical of by copyright. vagina possibly predominance Journal, 1, 1245. serotypes III and II of the organism in urinary MHALU, F.S. (1976) Infection with Streptococcus agalactiae tract infections in this study accords with the findings in a London hospital. Journal of Clinical Pathology, of Wilkinson et al. (1973) and of Anthony and Con- 29, 309. cepcion (1975). This relative prevalence of serotypes RANTZ, L.A. & RANDALL, E. (1955) Use of autoclaved III extracts of hemolytic streptococci for serological grouping. and II also conforms to their prevalence in the Stanford Medical Bulletin, 13, 290. genital tract of normal individuals (Finch et al., STOKES, E.J. & WATERWORTH, P.M. (1972) Association of 1976; Anthony and Concepcion, 1975). This seems Clinical Pathologists Broadsheet No. 55 (revised). to indicate that the serotypes which manage to WALLIN, J. & FORSGREN, A. (1975) Group B streptococci in cause disease in the tract do not have venereal disease clinic patients. British Journal of Venereal urinary any Diseases, 51, 401. http://pmj.bmj.com/ special characteristics. They simply occur according WILKINSON, H.W., FACKLAM, R.R. & WORTHAM, E.C. (1973) to their predominance in colonizing the normal Distribution by serological type of group B streptococci genital tract. isolated from a variety of clinical material over a five- year period (with special reference to and meningitis). Infection and Immunity, 8, 228. Acknowledgments Yow, M. (1974) Group B streptococci: a serious threat to This work was done while the author was on a World the neonate. Journal of American Medical Association, Health Organization fellowship grant, but the statements 230, 1177. on September 25, 2021 by guest. Protected