- Email: [email protected]
Urinary tract infection in adult men
Journal of Infection (1981) 3, 71-78
Urinary tract infection in adult men Linda Pead and Rosalind Maskell
Public Health Laboratory, St. Mary's General Hospital, Portsmouth
Summary Evidence is presented which challenges the widely held view that urinary tract infection (UTI) in adult men under 50 years of age is rare, and usually associated with structural or functional abnormalities. During a 14 month period, 999 men in the age group presented to their general practitioners with symptoms suggesting UTI; 223 had bacteriuria and 63 had 'sterile pyuria'. Details are given of their symptoms, their response to antibacterial treatment, and the radiological findings in those referred for hospital investigation. We suggest that infection probably originates in the prostate in many of these patients, that antibacterial agents which penetrate prostatic tissue should be used for treatment, and that a wider search for pathogenic organisms in those with 'sterile pyuria' is indicated.
Introduction
'Urinary tract infection in male children is almost restricted to those with congenital obstructive lesions, and is reasonably rare in young adult males except when associated with neurological disorders' (Black, 1967). This view of urinary tract infection (UTI) in males before the onset of prostatic enlargement in middle life has remained the accepted teaching, and text books continue to discuss U T I as a problem almost exclusively of the female sex. Some recent studies (Cohen, 1976; Hallett, Pead and Maskell, 1976; Khan, Ubriani, Bombach, Agbayani, Ratner and Evans, 1978), have demonstrated that acute U T I is not u n c o m m o n in boys, and that the majority of these children have radiologically normal urinary tracts. In an attempt to see whether this observation applies also to adult males we have sought information about the patients from whom urine specimens have been sent to our laboratory over the course of 14 months. Methods
From October 1977 to N o v e m b e r 1978 records were kept of all urine specimens sent to the laboratory by general practitioners or out-patient departments from m e n between the ages of 15 and 50 years inclusive. Microscopy of the deposit, after centrifugation at 1500 r/min for five minutes, was carried out, and the urine was plated with a 0. 005 ml standard 0163-4453/81/010071
+ 08 $01.00/0
© 1981 The British Society for the Study of Infection
. \\\
72
L. Pead a n d R. Maskell
loop on cysteine lactose electrolyte deficient (CLED) agar and incubated overnight at 37°C in air. Pyuria was defined as the presence of two or more white blood ceils per high power field (hpf). If the specimen showed 'sterile pyuria' a further specimen was usually requested; this was plated on blood agar and CLED agar and incubated anaerobically and in seven per cent CO2 for up to three days. All growths were recorded semi-quantitatively, and organisms were identified by standard methods (Cowan and Steel, 1976). Sensitivity testing was by a modified Stokes method (Pearson and Whitehead, 1974). If the specimen showed no cells on microscopy and no growth on culture it was classified as negative; presenting symptoms in patients from whom negative specimens were received were recorded from the request form. If, however, there was any abnormality on microscopy or culture, a questionnaire about symptoms and response to treatment was sent to the requesting practitioner one month later. Subsequently the X-ray reports of those patients referred for investigation to local hospitals were recorded, with the consent of the appropriate clinicians. Results We present the findings on 999 patients who presented to their general practitioners during the period of the study; patients with a previous history of urinary infection and those already under the care of hospital departments were excluded. The patients were divided into categories according to the MSU findings (Table I). Eighty-three per cent of the questionnaires sent to general practitioners were returned. Table I
Classification of 999 patients Age (years)
Category Single negative specimen. Group A Two or more negative specimens. Group B At least one specimen with cells, but no infection. Group C At least one specimen with infection. Group D Total
15-25
26-40
41-50
Total
189
279
136
604
25
34
16
75
26
37
34
97
52
107
64
223
292
457
250
999
Presenting symptoms
Table II shows the distribution of symptoms; the group of patients with cells only is subdivided into those with red cells only (Group C,a) and those with white cells with or without red cells (Group C,b).
Urinary tract infection in adult men Table II
Category
Presenting symptoms of 999 patients
Number of DysuriaJ patients frequency
Group A
604
Group B
75
Group C,a
34
Group C,b
63
Group D
223
73
375 (62) 45 (60) 12 (35) 40 (63) 180 (81)
Loin/ abdominal Fever/ Epididymo- Urethral pain Haematuriamalaise orchitis discharge 219 (36) 24 (32) 19 (56) 19 (30) 70 (31)
38 (6) 8 (11) 16 (47) 7 (11) 77 (35)
------2 (3) 18 (8)
28 (5) 4 (5) --5 (8) 3 (1)
11 (2) ----7 (11) 9 (4)
Percentages in brackets. Group C,a = red cells only. Group C,b = white cells +--red cells. The distribution of s y m p t o m s was almost identical t h r o u g h o u t the age range, with the exception of urethral discharge and epididymo-orchitis. T w e n t y - f o u r (89 per cent) of those with urethral discharge, and 36 (90 per cent) of those with epididymo-orchitis were under 40 y e a r s . Group C,a T h i r t y - f o u r patients had sterile specimens with red cells; as would be expected, there was a high incidence of loin pain (56 per cent) and r e p o r t e d h a e m a t u r i a (47 per cent). Two patients subsequently passed stones, and 14 were referred for hospital investigation. O n e of the latter was f o u n d to be in terminal renal failure due to glomerulonephritis, and the X-ray findings of 11 of the others are shown in Table VI. Group C,b Follow-up information was available in 32 of the 63 patients with white cells, with or without red cells, and no growth on culture. T w e n t y (91 per cent) of the 22 who were k n o w n to have had antibacterial t r e a t m e n t responded well, as did five of those who received no treatment. Seventeen patients in this group were referred for investigation, and the X-ray results of 12 are shown in Table VI. Culture for acid-fast bacilli was subsequently requested on four patients in this group, and was negative in all. Group D The organisms isolated from 223 patients are shown in Table III. Table IV shows the bacterial counts of Gram-negative and Gram-positive organisms and relates t h e m to the presence of pyuria. T r e a t m e n t information was available for 178 patients (Table V). The table includes the additional 31 courses of t r e a t m e n t given to patients who failed to respond to the first drug.
74
L. Pead and R. Maskell Table III Organisms isolated from 223 patients Group D Number of patients
Organism Gram-negative Esch. coli Proteus spp. Klebsiella spp. Acinetobacter spp. Enterobacter cloacae Coliform (not identified) Mixed Gram-positive Streptococcus faecal& Group B haemolytic strep Staphylococcus aureus Staphylococcus albus Gram-positive bacilli1" Mixed
92 14 6 4 1
28 30 10
3 1
10" 14 10
Total
223
*One strain was novobiocin-resistant. tGrew only after prolonged incubation in seven per cent CO2.
Table IV Bacterial count and pyuria in patients with infection
(Group D) Count (organisms/l)
A Organisms Gram-negative Gram-positive Total
Number
> 108
107-10 s
< 10r
Pyuria
175 48
91 (52) 7(15)
43(25) 23(48)
41 (23) 18(37)
96(55) 22(46)
223
98(44)
66(30)
59(26)
118(53)
(Percentages in brackets.)
One hundred and twenty-five courses of co-trimoxazole were given; the outcome was not known in 28 patients, and there was a satisfactory clinical response, with or without a check MSU, in 81 of the others (84 per cent). The success rate with ampicillin or amoxycillin was 50 per cent, and with sulphonamides 30 per cent. The difference in success rates of treatment with co-trimoxazole, ampicillin, and sulphonamide is statistically significant at the 0.1 per cent level (P < 0.001). Erythromycin sensitivity was reported only for Gram-positive bacilli, and there was 100 per cent success rate in the three patients who were treated with it. Thirty-one patients failed to respond to the first drug given. With the exception of co-trimoxazole, to which six out of the 11 organisms were resistant in vitro, 16 (80 per cent) of the remaining 20 organisms were sensitive tO the agent used unsuccessfully. Ten patients had a good clinical response, two with positive, and four with
Urinary tract infection in adult men
Follow-up of patients with infection
Table V
Treatment Co-trimoxazole Ampicillin/ amoxycillin Erythromycin Nalidixic acid Tetracycline Nitrofurantoin Sulphonamide Cephalosporin Penicillin V None
75
Number of courses given
Good CR* negative MSU
Good CR No MSU
No CR negative MSU
Poor or no response
Good CR positive MSU
Response not known
2rid drug needed
125
50
31
1
12
3
28
11
26 3
6 3
10
6
7 2 4 10 4 2 --
2 1 -2 --4
2 -I -1 -12
2 1 1 7 2 1 --
2 .
-.
f -2 1 l 1 4
6 .
2 .
.
--------
2 1 1 7 1 1 4
----1 -2
.
* C R = clinical r e s p o n s e .
negative follow-up specimens, without treatment. The initial cultures in these patients were mixed growths in counts of less than 10r/1 with one exception, who had a pure growth of Group B haemolytic streptococcus in a count of 107-108/1. Only 14 (six per cent) of the 223 patients had recurrence or persistence of infection during the period of the study. Seventy-one patients were referred for hospital investigation, including 13 of the 14 with recurrent infection. The X-ray findings in 54 of these patients were available, and are shown in Table VI. Table VI
X-ray findings in 77 of the 102 patients referred to hospital Category of patient
X - r a y finding
f G r o u p C,a r e d cells only
G r o u p C,b • w h i t e cells
Group D infection
IVP normal IVP normal. Residual urine Single n o r m a l k i d n e y Duplex kidney Pyelonephritic changes Polycystic k i d n e y s Stones Hydronephrosis with bladder neck obstruction N e o p l a s m of b l a d d e r Calcification o f s e m i n a l vesicles P o s t e r i o r u r e t h r a l stricture
3 2* ----4
6 1" --1 -4
-2
---
1 1
---
---
1 1
Total
11
12
54
*A!I p a t i e n t s w e r e o v e r 45 y e a r s .
35 5* 1 1 2 l 5
76
L. Pead and R. Maskell
The infecting organisms were analysed for patients with normal and abnormal radiology (Table VII). Eighteen (51 per cent) of the 35 patients with normal radiology, and ten (53 per cent) of the 19 patients with abnormal radiology had had bacterial counts of less than 108/1. X-ray results were available on 11 of the 14 patients with recurrent or persistent infection. Five (45 per cent) had abnormal radiology. Table V I I
Bacterial counts in patients with normal and abnormal radiology
Radiology Normal (35 patients) Abnormal (19 patients)
~ 108 17(49) 9(47)
Bacterial count A 10~-10s 6(17) 4(21)
< 10~ 12(34) 6(32)
(Percentages in brackets.)
Discussion
It is apparent that many men in the age group studied complain of symptoms referable to the urinary tract. Information was collected on all patients with bacteriuria, whether in high or low count. It seems that contamination of urine specimens, even when collected under the variable conditions of general practice, was uncommon, as 68 per cent of all the specimens from patients with symptoms were completely negative; it may, however, have accounted for the low counts of mixed organisms in nine of the patients who were known to recover without treatment. The finding that 223 'new' patients had urinary infection (74 per cent with bacterial counts of 107/1 or greater) during the course of the study demonstrates that the disease is not a rarity; 65 per cent of those investigated had normal radiology. Recurrent or persistent infection was rare, but was associated with radiological abnormality in 45 per cent of those investigated. Over half the patients with radiological abnormality had had bacterial counts of less than 10S/l, and 32 per cent had had infection with Grampositive organisms. These findings reinforce the view that low bacterial counts, and cultures of Gram-positive organisms, especially in pure culture, from urine obtained from men should not be disregarded as always due to contamination (Stamey, Govan and Palmer, 1965). It is possible that the site of infection in many of these patients may have been the prostate. This hypothesis accords with the evidence of the high cure rate with co-trimoxazole (the trimethoprim component of which attains a good concentration in prostatic tissue), (Carroll, Robb, Tippett and Langstrom, 1971), compared with that found with amoxycillin or sulphonamides (Winningham, Nemoy and Stamey, 1968). In 80 per cent of the treatment failures with the latter agents the infecting organism was sensitive in vitro, suggesting that an inadequate concentration may have been obtained in vivo.
Urinary tract infection in adult men
77
It is possible that prostatic infection does not result in the high bacterial counts usually associated with incubation of organisms in the bladder, an additional reason for not applying rigid numerical criteria. The predominance of Esch. coli and other coliforms (59 per cent) over Proteus (six per cent) in this study confirms our previous figures for adult male patients (Maskell, Pead and Hallett, 1975), and contrasts markedly with the high incidence of Proteus as a pathogen in boys (Hallett, Pead and Maskell, 1976; Khan, Ubriani, Bombach, Agbayani, Ratner and Evans, 1978). It seems possible that this is related in some way to prostatic function. The response to antibacterial treatment and the radiological findings in the group of patients with white cells present in urine but negative cultures were similar to those with infection. It is possible that these patients may, in fact, have had infections with slow-growing COz dependent organisms (Leopold, 1953; Abercrombie, Allen and Maskell, 1978; Maskell, Pead and Allen, 1979); on the few occasions in this study when we were able to obtain repeat specimens before treatment, 14 such organisms were isolated. Other organisms which are known to be pathogenic in the lower urinary tract are mycoplasmas and chlamydia, but the search for these organisms in this country has been mainly at the instigation of venereologists, whose patients usually complain of urethral discharge. Very few of the patients we describe had this symptom; such patients tend to be treated by general practitioners or urologists, and the bacteriological techniques for diagnosis are usually limited to a search for the aerobic urinary pathogens. Possibly the distressing complaint of chronic prostatitis might be prevented in some patients if a wider search for pathogenic organisms was made at an early stage; we suggest that all laboratories, whether or not they have facilities for mycoplasma and chlamydia culture, should examine urines with unexplained persistent pyuria by prolonged incubation in COz. (We thank the many general practitioners who co-operated in this study by returning questionnaires, Mr John Lobb for statistical advice, and Mrs T. Diplock for invaluable secretarial help.)
References
Abercrombie, G. F., Allen, J. and Maskell, R. (1978). Corynebacterium vaginale urinary tract infection in a man. Lancet, i, 766. Black, D. A. K. Renal Disease. 2nd ed. Blackwell Scientific Publications, Oxford and Edinburgh (1967), p. 386. Carroll, P. T., Robb, C. A., Tippett, L. O. and Langstrom, J. B. (1971). Antibacterial activity of diaveridine, trimethoprim and selected sulphonamides in prostatic fluid. Investigative Urology, 8, 686. Cohen, M. (1976). The first urinary tract infection in male children. American Journal of Diseases in Childhood, 130, 810. Cowan, S. T. and Steel, K. J. Manual for the Identification of Medical Bacteria. Cambridge University Press, London (1976).
78
L. Pead and R. Maskell
Hatlett, R. J., Pead, L. and Maskell, R. (1976). Urinary tract infection in boys. Lancet, ii, 1107. Khan, A. J., Ubriani, R. S., Bombach, E., Agbayani, M. M., Ratner, H. and Evans, H. E. (1978). Initial urinary tract infection caused by Proteus mirabilis in infancy and childhood. Journal of Pediatrics, 93, 791. Leopold, S. (1953). Heretofore undescribed organism isolated from the genito-urinary system. U.S. Armed Forces Medical Journal, 4, 263. Maskell, R., Pead, L. and Hallett, R. J. (1975). Urinary pathogens in the male. BritishJournal of Urology, 47, 691. Maskell, R., Pead, L. and Allen, J. (1979). The puzzle of 'urethral syndrome'; a possible answer? Lancet, i, 1058. Pearson, C. H. and Whitehead, J. E. M. (1974). Antibiotic sensitivity testing: a modification of the Stokes method using a rotary plater. Journal of Clinical Pathology, 27, 430. Stamey, T. A., Govan, M. D. and Palmer, J. M. (1965). The localization and treatment of urinary tract infections: the role of bactericidal urine levels as opposed to serum levels. Medicine, 44, 1. Winningham, D. G., Nemoy, N. J. and Stamey, T. A. (1968). Diffusion of antibiotics from plasma into prostatic fluid. Nature, 219, 139.
Urinary tract infection in adult men Linda Pead and Rosalind Maskell
Public Health Laboratory, St. Mary's General Hospital, Portsmouth
Summary Evidence is presented which challenges the widely held view that urinary tract infection (UTI) in adult men under 50 years of age is rare, and usually associated with structural or functional abnormalities. During a 14 month period, 999 men in the age group presented to their general practitioners with symptoms suggesting UTI; 223 had bacteriuria and 63 had 'sterile pyuria'. Details are given of their symptoms, their response to antibacterial treatment, and the radiological findings in those referred for hospital investigation. We suggest that infection probably originates in the prostate in many of these patients, that antibacterial agents which penetrate prostatic tissue should be used for treatment, and that a wider search for pathogenic organisms in those with 'sterile pyuria' is indicated.
Introduction
'Urinary tract infection in male children is almost restricted to those with congenital obstructive lesions, and is reasonably rare in young adult males except when associated with neurological disorders' (Black, 1967). This view of urinary tract infection (UTI) in males before the onset of prostatic enlargement in middle life has remained the accepted teaching, and text books continue to discuss U T I as a problem almost exclusively of the female sex. Some recent studies (Cohen, 1976; Hallett, Pead and Maskell, 1976; Khan, Ubriani, Bombach, Agbayani, Ratner and Evans, 1978), have demonstrated that acute U T I is not u n c o m m o n in boys, and that the majority of these children have radiologically normal urinary tracts. In an attempt to see whether this observation applies also to adult males we have sought information about the patients from whom urine specimens have been sent to our laboratory over the course of 14 months. Methods
From October 1977 to N o v e m b e r 1978 records were kept of all urine specimens sent to the laboratory by general practitioners or out-patient departments from m e n between the ages of 15 and 50 years inclusive. Microscopy of the deposit, after centrifugation at 1500 r/min for five minutes, was carried out, and the urine was plated with a 0. 005 ml standard 0163-4453/81/010071
+ 08 $01.00/0
© 1981 The British Society for the Study of Infection
. \\\
72
L. Pead a n d R. Maskell
loop on cysteine lactose electrolyte deficient (CLED) agar and incubated overnight at 37°C in air. Pyuria was defined as the presence of two or more white blood ceils per high power field (hpf). If the specimen showed 'sterile pyuria' a further specimen was usually requested; this was plated on blood agar and CLED agar and incubated anaerobically and in seven per cent CO2 for up to three days. All growths were recorded semi-quantitatively, and organisms were identified by standard methods (Cowan and Steel, 1976). Sensitivity testing was by a modified Stokes method (Pearson and Whitehead, 1974). If the specimen showed no cells on microscopy and no growth on culture it was classified as negative; presenting symptoms in patients from whom negative specimens were received were recorded from the request form. If, however, there was any abnormality on microscopy or culture, a questionnaire about symptoms and response to treatment was sent to the requesting practitioner one month later. Subsequently the X-ray reports of those patients referred for investigation to local hospitals were recorded, with the consent of the appropriate clinicians. Results We present the findings on 999 patients who presented to their general practitioners during the period of the study; patients with a previous history of urinary infection and those already under the care of hospital departments were excluded. The patients were divided into categories according to the MSU findings (Table I). Eighty-three per cent of the questionnaires sent to general practitioners were returned. Table I
Classification of 999 patients Age (years)
Category Single negative specimen. Group A Two or more negative specimens. Group B At least one specimen with cells, but no infection. Group C At least one specimen with infection. Group D Total
15-25
26-40
41-50
Total
189
279
136
604
25
34
16
75
26
37
34
97
52
107
64
223
292
457
250
999
Presenting symptoms
Table II shows the distribution of symptoms; the group of patients with cells only is subdivided into those with red cells only (Group C,a) and those with white cells with or without red cells (Group C,b).
Urinary tract infection in adult men Table II
Category
Presenting symptoms of 999 patients
Number of DysuriaJ patients frequency
Group A
604
Group B
75
Group C,a
34
Group C,b
63
Group D
223
73
375 (62) 45 (60) 12 (35) 40 (63) 180 (81)
Loin/ abdominal Fever/ Epididymo- Urethral pain Haematuriamalaise orchitis discharge 219 (36) 24 (32) 19 (56) 19 (30) 70 (31)
38 (6) 8 (11) 16 (47) 7 (11) 77 (35)
------2 (3) 18 (8)
28 (5) 4 (5) --5 (8) 3 (1)
11 (2) ----7 (11) 9 (4)
Percentages in brackets. Group C,a = red cells only. Group C,b = white cells +--red cells. The distribution of s y m p t o m s was almost identical t h r o u g h o u t the age range, with the exception of urethral discharge and epididymo-orchitis. T w e n t y - f o u r (89 per cent) of those with urethral discharge, and 36 (90 per cent) of those with epididymo-orchitis were under 40 y e a r s . Group C,a T h i r t y - f o u r patients had sterile specimens with red cells; as would be expected, there was a high incidence of loin pain (56 per cent) and r e p o r t e d h a e m a t u r i a (47 per cent). Two patients subsequently passed stones, and 14 were referred for hospital investigation. O n e of the latter was f o u n d to be in terminal renal failure due to glomerulonephritis, and the X-ray findings of 11 of the others are shown in Table VI. Group C,b Follow-up information was available in 32 of the 63 patients with white cells, with or without red cells, and no growth on culture. T w e n t y (91 per cent) of the 22 who were k n o w n to have had antibacterial t r e a t m e n t responded well, as did five of those who received no treatment. Seventeen patients in this group were referred for investigation, and the X-ray results of 12 are shown in Table VI. Culture for acid-fast bacilli was subsequently requested on four patients in this group, and was negative in all. Group D The organisms isolated from 223 patients are shown in Table III. Table IV shows the bacterial counts of Gram-negative and Gram-positive organisms and relates t h e m to the presence of pyuria. T r e a t m e n t information was available for 178 patients (Table V). The table includes the additional 31 courses of t r e a t m e n t given to patients who failed to respond to the first drug.
74
L. Pead and R. Maskell Table III Organisms isolated from 223 patients Group D Number of patients
Organism Gram-negative Esch. coli Proteus spp. Klebsiella spp. Acinetobacter spp. Enterobacter cloacae Coliform (not identified) Mixed Gram-positive Streptococcus faecal& Group B haemolytic strep Staphylococcus aureus Staphylococcus albus Gram-positive bacilli1" Mixed
92 14 6 4 1
28 30 10
3 1
10" 14 10
Total
223
*One strain was novobiocin-resistant. tGrew only after prolonged incubation in seven per cent CO2.
Table IV Bacterial count and pyuria in patients with infection
(Group D) Count (organisms/l)
A Organisms Gram-negative Gram-positive Total
Number
> 108
107-10 s
< 10r
Pyuria
175 48
91 (52) 7(15)
43(25) 23(48)
41 (23) 18(37)
96(55) 22(46)
223
98(44)
66(30)
59(26)
118(53)
(Percentages in brackets.)
One hundred and twenty-five courses of co-trimoxazole were given; the outcome was not known in 28 patients, and there was a satisfactory clinical response, with or without a check MSU, in 81 of the others (84 per cent). The success rate with ampicillin or amoxycillin was 50 per cent, and with sulphonamides 30 per cent. The difference in success rates of treatment with co-trimoxazole, ampicillin, and sulphonamide is statistically significant at the 0.1 per cent level (P < 0.001). Erythromycin sensitivity was reported only for Gram-positive bacilli, and there was 100 per cent success rate in the three patients who were treated with it. Thirty-one patients failed to respond to the first drug given. With the exception of co-trimoxazole, to which six out of the 11 organisms were resistant in vitro, 16 (80 per cent) of the remaining 20 organisms were sensitive tO the agent used unsuccessfully. Ten patients had a good clinical response, two with positive, and four with
Urinary tract infection in adult men
Follow-up of patients with infection
Table V
Treatment Co-trimoxazole Ampicillin/ amoxycillin Erythromycin Nalidixic acid Tetracycline Nitrofurantoin Sulphonamide Cephalosporin Penicillin V None
75
Number of courses given
Good CR* negative MSU
Good CR No MSU
No CR negative MSU
Poor or no response
Good CR positive MSU
Response not known
2rid drug needed
125
50
31
1
12
3
28
11
26 3
6 3
10
6
7 2 4 10 4 2 --
2 1 -2 --4
2 -I -1 -12
2 1 1 7 2 1 --
2 .
-.
f -2 1 l 1 4
6 .
2 .
.
--------
2 1 1 7 1 1 4
----1 -2
.
* C R = clinical r e s p o n s e .
negative follow-up specimens, without treatment. The initial cultures in these patients were mixed growths in counts of less than 10r/1 with one exception, who had a pure growth of Group B haemolytic streptococcus in a count of 107-108/1. Only 14 (six per cent) of the 223 patients had recurrence or persistence of infection during the period of the study. Seventy-one patients were referred for hospital investigation, including 13 of the 14 with recurrent infection. The X-ray findings in 54 of these patients were available, and are shown in Table VI. Table VI
X-ray findings in 77 of the 102 patients referred to hospital Category of patient
X - r a y finding
f G r o u p C,a r e d cells only
G r o u p C,b • w h i t e cells
Group D infection
IVP normal IVP normal. Residual urine Single n o r m a l k i d n e y Duplex kidney Pyelonephritic changes Polycystic k i d n e y s Stones Hydronephrosis with bladder neck obstruction N e o p l a s m of b l a d d e r Calcification o f s e m i n a l vesicles P o s t e r i o r u r e t h r a l stricture
3 2* ----4
6 1" --1 -4
-2
---
1 1
---
---
1 1
Total
11
12
54
*A!I p a t i e n t s w e r e o v e r 45 y e a r s .
35 5* 1 1 2 l 5
76
L. Pead and R. Maskell
The infecting organisms were analysed for patients with normal and abnormal radiology (Table VII). Eighteen (51 per cent) of the 35 patients with normal radiology, and ten (53 per cent) of the 19 patients with abnormal radiology had had bacterial counts of less than 108/1. X-ray results were available on 11 of the 14 patients with recurrent or persistent infection. Five (45 per cent) had abnormal radiology. Table V I I
Bacterial counts in patients with normal and abnormal radiology
Radiology Normal (35 patients) Abnormal (19 patients)
~ 108 17(49) 9(47)
Bacterial count A 10~-10s 6(17) 4(21)
< 10~ 12(34) 6(32)
(Percentages in brackets.)
Discussion
It is apparent that many men in the age group studied complain of symptoms referable to the urinary tract. Information was collected on all patients with bacteriuria, whether in high or low count. It seems that contamination of urine specimens, even when collected under the variable conditions of general practice, was uncommon, as 68 per cent of all the specimens from patients with symptoms were completely negative; it may, however, have accounted for the low counts of mixed organisms in nine of the patients who were known to recover without treatment. The finding that 223 'new' patients had urinary infection (74 per cent with bacterial counts of 107/1 or greater) during the course of the study demonstrates that the disease is not a rarity; 65 per cent of those investigated had normal radiology. Recurrent or persistent infection was rare, but was associated with radiological abnormality in 45 per cent of those investigated. Over half the patients with radiological abnormality had had bacterial counts of less than 10S/l, and 32 per cent had had infection with Grampositive organisms. These findings reinforce the view that low bacterial counts, and cultures of Gram-positive organisms, especially in pure culture, from urine obtained from men should not be disregarded as always due to contamination (Stamey, Govan and Palmer, 1965). It is possible that the site of infection in many of these patients may have been the prostate. This hypothesis accords with the evidence of the high cure rate with co-trimoxazole (the trimethoprim component of which attains a good concentration in prostatic tissue), (Carroll, Robb, Tippett and Langstrom, 1971), compared with that found with amoxycillin or sulphonamides (Winningham, Nemoy and Stamey, 1968). In 80 per cent of the treatment failures with the latter agents the infecting organism was sensitive in vitro, suggesting that an inadequate concentration may have been obtained in vivo.
Urinary tract infection in adult men
77
It is possible that prostatic infection does not result in the high bacterial counts usually associated with incubation of organisms in the bladder, an additional reason for not applying rigid numerical criteria. The predominance of Esch. coli and other coliforms (59 per cent) over Proteus (six per cent) in this study confirms our previous figures for adult male patients (Maskell, Pead and Hallett, 1975), and contrasts markedly with the high incidence of Proteus as a pathogen in boys (Hallett, Pead and Maskell, 1976; Khan, Ubriani, Bombach, Agbayani, Ratner and Evans, 1978). It seems possible that this is related in some way to prostatic function. The response to antibacterial treatment and the radiological findings in the group of patients with white cells present in urine but negative cultures were similar to those with infection. It is possible that these patients may, in fact, have had infections with slow-growing COz dependent organisms (Leopold, 1953; Abercrombie, Allen and Maskell, 1978; Maskell, Pead and Allen, 1979); on the few occasions in this study when we were able to obtain repeat specimens before treatment, 14 such organisms were isolated. Other organisms which are known to be pathogenic in the lower urinary tract are mycoplasmas and chlamydia, but the search for these organisms in this country has been mainly at the instigation of venereologists, whose patients usually complain of urethral discharge. Very few of the patients we describe had this symptom; such patients tend to be treated by general practitioners or urologists, and the bacteriological techniques for diagnosis are usually limited to a search for the aerobic urinary pathogens. Possibly the distressing complaint of chronic prostatitis might be prevented in some patients if a wider search for pathogenic organisms was made at an early stage; we suggest that all laboratories, whether or not they have facilities for mycoplasma and chlamydia culture, should examine urines with unexplained persistent pyuria by prolonged incubation in COz. (We thank the many general practitioners who co-operated in this study by returning questionnaires, Mr John Lobb for statistical advice, and Mrs T. Diplock for invaluable secretarial help.)
References
Abercrombie, G. F., Allen, J. and Maskell, R. (1978). Corynebacterium vaginale urinary tract infection in a man. Lancet, i, 766. Black, D. A. K. Renal Disease. 2nd ed. Blackwell Scientific Publications, Oxford and Edinburgh (1967), p. 386. Carroll, P. T., Robb, C. A., Tippett, L. O. and Langstrom, J. B. (1971). Antibacterial activity of diaveridine, trimethoprim and selected sulphonamides in prostatic fluid. Investigative Urology, 8, 686. Cohen, M. (1976). The first urinary tract infection in male children. American Journal of Diseases in Childhood, 130, 810. Cowan, S. T. and Steel, K. J. Manual for the Identification of Medical Bacteria. Cambridge University Press, London (1976).
78
L. Pead and R. Maskell
Hatlett, R. J., Pead, L. and Maskell, R. (1976). Urinary tract infection in boys. Lancet, ii, 1107. Khan, A. J., Ubriani, R. S., Bombach, E., Agbayani, M. M., Ratner, H. and Evans, H. E. (1978). Initial urinary tract infection caused by Proteus mirabilis in infancy and childhood. Journal of Pediatrics, 93, 791. Leopold, S. (1953). Heretofore undescribed organism isolated from the genito-urinary system. U.S. Armed Forces Medical Journal, 4, 263. Maskell, R., Pead, L. and Hallett, R. J. (1975). Urinary pathogens in the male. BritishJournal of Urology, 47, 691. Maskell, R., Pead, L. and Allen, J. (1979). The puzzle of 'urethral syndrome'; a possible answer? Lancet, i, 1058. Pearson, C. H. and Whitehead, J. E. M. (1974). Antibiotic sensitivity testing: a modification of the Stokes method using a rotary plater. Journal of Clinical Pathology, 27, 430. Stamey, T. A., Govan, M. D. and Palmer, J. M. (1965). The localization and treatment of urinary tract infections: the role of bactericidal urine levels as opposed to serum levels. Medicine, 44, 1. Winningham, D. G., Nemoy, N. J. and Stamey, T. A. (1968). Diffusion of antibiotics from plasma into prostatic fluid. Nature, 219, 139.