Aust N Z J Med (1977). 7, pp 56-59
Torulopsis Glabrata-Urinary Patients in Singapore
Tract Infections in Diabetic
Rowland J. S. Tan*, Ek-Wang Limt and Baharudin lshakl
From the Department of Microbiology, Faculty of Medicine, University of Singapore
Summary: Torulopsis gfabrata- Urinary tract infections in diabetic patients in Singapore. Rowland J. S. Tan, Ek-Wang Lim and Baharudin Ishak, Aust. N.Z. J. Med., 1977. 7. pp 56-59. Urinary tract infections result mostly from ascending infection by micro - organisms introduced by way of the urethra. Bacteria are the usual causative agents, Occasionally, yeasts notably Candida al bicans, are involved. Females are more prone to acute infections than males because of shorter urethra and the higher risks of contamination in the females.
In Singapore, E. coli, Klebsiellu spp., Enterobacter aerogenes, Proteus spp., Pseudornonus spp. and Achromohucter spp. accounted for over 86", of all urinary tract infections.' Urinary tract infections due to Candida albicans occurred in only 0.3", of cases.' However, urinary tract infection due to another yeast, Torulopsis ylabratu was, hitherto, unknown in Singapore.' Very recently Torulopsis glabrata was isolated from urine specimens of nine patients suffering from urinary tract infections complicated by diabetes mellitus. This paper reports on the isolation of Torulopsis glabruta from urine specimens and describes the significance of T. ylabrata in these compromised patients. Materials and Methods
All the clinical specimens received at the Mycology Laboratory were immediately streaked onto Sabouraud Dextrose Agar with and without chloramphenicol and cycloheximide. The plates or slants were incubated at room temperature (25 C ) for two days before they were read. Positive isolates were inoculated into fermentation and assimilation tubes according to the method described by Silva-Hutner and Cooper.' Those isolates suspected of T. glahrata were also streaked onto blood agar.
"Lecturer. tResearch Technician. :Assistant Research Technician. Correspondence Dr. Rowland J. S. Tan, Department of Microbiology, Faculty of Medicine, University of Singapore, Singapore 3 Accepted for publication. 18 October, 1976
T. ylcihrorn ferments only glucose and assimilates glucose and trehalose. On blood agar, it produces small white to cream-coloured colonies approximately 0.5-1.5 mm in diameter as compared to C. ulhic-uns which produces big white colonies about 3-4 mm in diameter. Microscopic examination reveals globose to ovoid cells with no ascospores or pseudohyphae. The small-sized colonies on blood agar and the characteristic sugar fermentation and assimilation patterns clearly distinguish T. glnhrura from other yeasts. Two local strains of T. ylahrnra (P.25 and F.125) were confirmed by Dr. D. W. R. Mackenzie of the Mycological Reference Laboratory, London School of Hygiene and Tropical Medicine, England. Results
There were nine patients, all were diabetics and were women between the ages of 40 and 65. There were three Chinese, five Malay and one Indian women in this group. All of them complained of frequency of micturition and dysuria, as shown in Table 1. Four patients presented with fever. Haematuria (1 patient), pyuria (l), costovertebral tenderness (3). and lower abdominal pain ( 1 1 were the other symptoms recorded. Three patients had had one previously documented infection and one had had two previously documented infections. The latter patient, age 65, died of massive pulmonary embolism two months after the second recurrent infection. Cultures from mid-stream urine of all nine patients gave pure growth of T. ylabrutu. In two patients, repeat cultures from mid-stream urine were made daily for one week during treatment. T. glabrata was isolated from urine cultures during the first three days of treatment, but was absent from subsequent urine specimens. All the patients including those who had had previous infection recovered after amphotericin B or 5-fluorocytosine administration. Urine specimens were negative for T. glabrata from all recovered patients. Discussion
Urinary tract infections of bacterial origin are very ~ o m r n o nHowever, .~ urinary tract infections
FEBRUARY,
1977
57
URINARY INFECTIONS WITH TORULOPSIS GLABRATA
caused by yeasts such as Candida albicans and Torulopsis glubrata are quite rare.' T. glabruta is a yeast-like micro-organism with globose to elongated cell. It reproduces by multipolar budding but fails to produce septate hyphae or ascospores. On Sabouraud Dextrose Agar, the colonies are white or cream-coloured and have no carotenoid pigments." Like C. albicuns, T. glubrata is widely distributed in man and animals.' Evidence of its pathogenicity in healthy animals has not been consistent. Lodder and De Vries6 injected T. glabruta intracardially into five rats. Three died within three months, and T. glabrata was isolated from autopsied lungs of all the animals. However, in a subsequent study, Lodder and De Minjer7 found no pathological changes in a number of mice and rats following inoculation of T . glabrata intraperitoneally and also subcutaneously. They concluded that T . glabrata was not pathogenic for mice and rats. Fernandez' studied the pathogenicity of T. glabruta in a number of animals, including rabbits, guinea-pigs, rats and mice. He found that most of the animals were prone to infection, mice being the most susceptible animals. The characteristic pathological feature was the formation of nodular lesions with an intense elaboration of reticuloendothelial cells. Minkowitz er aL9 were able to produce typical lesions in mice by the intravenous and peritoneal routes. The virulence and tissue invasion by T. glabrata in mice was reportedly enhanced by the administration of steroids, X-irradiation and alloxan." In humans, T. glabrata is essentially a saprophyte which can establish itself as part of the normal microflora in the gastrointestinal and genito-urinary tracts. However, in the presence of pre-disposing factors such as diabetes mellitus, cancers or major surgical operations, T. glabrata has been reported responsible for a number of clinical mycoses." The localization of 7'. glabruta in the gastrointestinal and genito-urinary tracts, invariably, provides a convenient source of endogenous infection.12 The clinical data (Table 1 ) support the hypothesis that T. glabrata plays an important role in urinary tract infections in compromised hosts, i.e. patients with diabetes mellitus. Stab-
TABLE 1 Presenting symptoms of urinary tract infections in nine patients with Torulopsis glabratu Symptoms Fever Dysuria Haematuria Pyuria Frequency Loin pain (costovertebral tenderness) Lower abdominal pain Presence of T glahraro in stool Recurrent infection: Once Twice
No. of patients 4 9 1 1 9 7
&
I 4 3 1
ilization of diabetes did not help to clear T. ylabratcc from urine of patients with such infection. T. glabrura was isolated in pure cultures and in significant numbers (more than lo5 micro-organisms per ml) from mid-stream urine specimens. No bacteria were recovered from any of the urine specimens, suggesting that T. glabrata was the primary pathogen. These patients had dysuria and frequency of micturition as common symptoms associated with urinary tract infections. Four patients had had previously documented infections. T. glabrata was again the primary pathogen as it was isolated in pure cultures from urine specimens. All of them responded very well to either amphotericin B or 5-Auorocytosine administration. T. glabrata was completely eradicated from the urinary tracts of all recovered patients. Hence, the disappearance of symptoms following amphotericin B or 5-fluorocytosine treatment, the continued absence of bacteria from urine specimens and the absence of T. glabrata from urine specimens three days after treatment alblend support to T. glabrata being the most probable causative agent. The role of diabetes mellitus as an important pre-disposing factor to T. glabrata infection is well documented.l3-1 4 , 1 5 , l 6 Hyperglycaemia in diabetes mellitus has been demonstrated to inhibit phagocytosis by polymorpho-nuclear leukocytes.' Acidosis in these patients may further contribute to enhanced fungal dissemination into deeper tissues.I8 Ahearn et al.I3 recovered T. glabratu from 45 out of 1013 urine specimens and found that nine of the patients had diabetes mellitus.
58
TAN ET AL.
Speller14 reported two diabetic patients with T. glubrata urinary tract infections. The yeast was recovered from mid-stream urine of one patient for a continuous period of six months. No bacteria were isolated from all the specimens. Guze and Haley16 demonstrated T. glabrara in seven patients with urinary tract infections. Four of them were diabetics. Edebo and Spetz15 also reported a case of urinary tract infection caused by T glubruta in a diabetic patient who was subsequently treated by increasing the pH of the urine with sodium citrate. Treatment of patients with fungal urinary tract infections is often difficult." Before the advent of 5-fluorocytosine, most of the patients with urinary tract infections caused by yeasts were given intravenous infusions of amphotericin B.19 In T. glabratu infections, amphotericin B has been found to be most active in in uitro studies.20 However, it is well known that amphotericin B is highly toxic and has to be administered intravenously.21 Some authorities recommend bladder irrigation with amphotericin B in clearing lower urinary tract yeast infections, reserving the relatively toxic parenteral amphotericin B for cases with evidence of severe or disseminated tissue infection. 5-fluorocytosine is less toxic and is well absorbed orally.22 High serum and urine levels can be obtained in patients with normal renal function as well as those with moderate to severe renal impairment. were the first workers to Grunberg et employ 5-fluorocytosine in treating experimental mouse candidiasis. Since then, it has been the drug of choice in treating mycotic infections caused by Candida, Cryptococcus and Tordopsis species.14. 2 4 , 2 5 , 2 6 Unfortunately, strains of T. glubrata resistant to 5-fluorocytosine have occasionally emerged during in zlitro testing.22 Steer et al.27 reported two cases of chronic pyelonephritis caused by T. glubrata in two diabetic patients who failed to respond to 5fluorocytosine. They suggested that the administration of 5-fluorocytosine should be carefully monitored in patients during treatment. A daily dosage of 100-150 mg/kg body weight has been found adequate in treating Candida and Torulopsis infection^.'^ However, this dosage must be reduced in patients with moderate
VOL.
7,
NO.
1
renal impairment. In those with severe renal impairment, monitoring of plasma concentrations is essential. In addition, in zlitro sensitivity testing of 7'. glabruta to 5-fluorocytosine should always be carried out, in view of its likely resistance to the drug. Our findings together with the cases reported by other workers", 14, 2 0 , 27 strongly suggest that the frequency of urinary tract infections caused by T. glubrata could be higher than was previously suspected by clinical microbiologists. Greater awareness of the biochemical and morphological characteristics of T. glabraru and of its opportunistic pathogenicity in compromised hosts may enhance recognition of T. glabrata from clinical specimens. ,
Acknowledgements
We are indebted to Dr. D. W. R. MacKenzie of the Mycological Laboratory, London School of Hygiene and Tropical Medicine, England for confirming our 2'. gluhrutu isolates.
References 1. TAN,R J . S . , LIM. E W . and T s i . H R (1976): A survey ofurinary tract infections in Singapore-a 3 year study (In preparation.) 2. SILVA-HUTNER, M. and COOPER. B. H. (1974): Medically important yeasts. In: Munual of Clinxul Microbiology, ed. Lennette, E. H., Spaulding, E H. and Truant, J. P., 2nd. Edition, Amer. Soc. Microbiol, U S A . , p 491 3 SAhFoRn, J P. (1975). Urinary tract symptoms and infections, Ann. Rev. Med. 26, 485. 4. ~OCKlWA-l
Torulopsis Glabrata-Urinary Patients in Singapore
Tract Infections in Diabetic
Rowland J. S. Tan*, Ek-Wang Limt and Baharudin lshakl
From the Department of Microbiology, Faculty of Medicine, University of Singapore
Summary: Torulopsis gfabrata- Urinary tract infections in diabetic patients in Singapore. Rowland J. S. Tan, Ek-Wang Lim and Baharudin Ishak, Aust. N.Z. J. Med., 1977. 7. pp 56-59. Urinary tract infections result mostly from ascending infection by micro - organisms introduced by way of the urethra. Bacteria are the usual causative agents, Occasionally, yeasts notably Candida al bicans, are involved. Females are more prone to acute infections than males because of shorter urethra and the higher risks of contamination in the females.
In Singapore, E. coli, Klebsiellu spp., Enterobacter aerogenes, Proteus spp., Pseudornonus spp. and Achromohucter spp. accounted for over 86", of all urinary tract infections.' Urinary tract infections due to Candida albicans occurred in only 0.3", of cases.' However, urinary tract infection due to another yeast, Torulopsis ylabratu was, hitherto, unknown in Singapore.' Very recently Torulopsis glabrata was isolated from urine specimens of nine patients suffering from urinary tract infections complicated by diabetes mellitus. This paper reports on the isolation of Torulopsis glabruta from urine specimens and describes the significance of T. ylabrata in these compromised patients. Materials and Methods
All the clinical specimens received at the Mycology Laboratory were immediately streaked onto Sabouraud Dextrose Agar with and without chloramphenicol and cycloheximide. The plates or slants were incubated at room temperature (25 C ) for two days before they were read. Positive isolates were inoculated into fermentation and assimilation tubes according to the method described by Silva-Hutner and Cooper.' Those isolates suspected of T. glahrata were also streaked onto blood agar.
"Lecturer. tResearch Technician. :Assistant Research Technician. Correspondence Dr. Rowland J. S. Tan, Department of Microbiology, Faculty of Medicine, University of Singapore, Singapore 3 Accepted for publication. 18 October, 1976
T. ylcihrorn ferments only glucose and assimilates glucose and trehalose. On blood agar, it produces small white to cream-coloured colonies approximately 0.5-1.5 mm in diameter as compared to C. ulhic-uns which produces big white colonies about 3-4 mm in diameter. Microscopic examination reveals globose to ovoid cells with no ascospores or pseudohyphae. The small-sized colonies on blood agar and the characteristic sugar fermentation and assimilation patterns clearly distinguish T. glnhrura from other yeasts. Two local strains of T. ylahrnra (P.25 and F.125) were confirmed by Dr. D. W. R. Mackenzie of the Mycological Reference Laboratory, London School of Hygiene and Tropical Medicine, England. Results
There were nine patients, all were diabetics and were women between the ages of 40 and 65. There were three Chinese, five Malay and one Indian women in this group. All of them complained of frequency of micturition and dysuria, as shown in Table 1. Four patients presented with fever. Haematuria (1 patient), pyuria (l), costovertebral tenderness (3). and lower abdominal pain ( 1 1 were the other symptoms recorded. Three patients had had one previously documented infection and one had had two previously documented infections. The latter patient, age 65, died of massive pulmonary embolism two months after the second recurrent infection. Cultures from mid-stream urine of all nine patients gave pure growth of T. ylabrutu. In two patients, repeat cultures from mid-stream urine were made daily for one week during treatment. T. glabrata was isolated from urine cultures during the first three days of treatment, but was absent from subsequent urine specimens. All the patients including those who had had previous infection recovered after amphotericin B or 5-fluorocytosine administration. Urine specimens were negative for T. glabrata from all recovered patients. Discussion
Urinary tract infections of bacterial origin are very ~ o m r n o nHowever, .~ urinary tract infections
FEBRUARY,
1977
57
URINARY INFECTIONS WITH TORULOPSIS GLABRATA
caused by yeasts such as Candida albicans and Torulopsis glubrata are quite rare.' T. glabruta is a yeast-like micro-organism with globose to elongated cell. It reproduces by multipolar budding but fails to produce septate hyphae or ascospores. On Sabouraud Dextrose Agar, the colonies are white or cream-coloured and have no carotenoid pigments." Like C. albicuns, T. glubrata is widely distributed in man and animals.' Evidence of its pathogenicity in healthy animals has not been consistent. Lodder and De Vries6 injected T. glabruta intracardially into five rats. Three died within three months, and T. glabrata was isolated from autopsied lungs of all the animals. However, in a subsequent study, Lodder and De Minjer7 found no pathological changes in a number of mice and rats following inoculation of T . glabrata intraperitoneally and also subcutaneously. They concluded that T . glabrata was not pathogenic for mice and rats. Fernandez' studied the pathogenicity of T. glabruta in a number of animals, including rabbits, guinea-pigs, rats and mice. He found that most of the animals were prone to infection, mice being the most susceptible animals. The characteristic pathological feature was the formation of nodular lesions with an intense elaboration of reticuloendothelial cells. Minkowitz er aL9 were able to produce typical lesions in mice by the intravenous and peritoneal routes. The virulence and tissue invasion by T. glabrata in mice was reportedly enhanced by the administration of steroids, X-irradiation and alloxan." In humans, T. glabrata is essentially a saprophyte which can establish itself as part of the normal microflora in the gastrointestinal and genito-urinary tracts. However, in the presence of pre-disposing factors such as diabetes mellitus, cancers or major surgical operations, T. glabrata has been reported responsible for a number of clinical mycoses." The localization of 7'. glabruta in the gastrointestinal and genito-urinary tracts, invariably, provides a convenient source of endogenous infection.12 The clinical data (Table 1 ) support the hypothesis that T. glabrata plays an important role in urinary tract infections in compromised hosts, i.e. patients with diabetes mellitus. Stab-
TABLE 1 Presenting symptoms of urinary tract infections in nine patients with Torulopsis glabratu Symptoms Fever Dysuria Haematuria Pyuria Frequency Loin pain (costovertebral tenderness) Lower abdominal pain Presence of T glahraro in stool Recurrent infection: Once Twice
No. of patients 4 9 1 1 9 7
&
I 4 3 1
ilization of diabetes did not help to clear T. ylabratcc from urine of patients with such infection. T. glabrura was isolated in pure cultures and in significant numbers (more than lo5 micro-organisms per ml) from mid-stream urine specimens. No bacteria were recovered from any of the urine specimens, suggesting that T. glabrata was the primary pathogen. These patients had dysuria and frequency of micturition as common symptoms associated with urinary tract infections. Four patients had had previously documented infections. T. glabrata was again the primary pathogen as it was isolated in pure cultures from urine specimens. All of them responded very well to either amphotericin B or 5-Auorocytosine administration. T. glabrata was completely eradicated from the urinary tracts of all recovered patients. Hence, the disappearance of symptoms following amphotericin B or 5-fluorocytosine treatment, the continued absence of bacteria from urine specimens and the absence of T. glabrata from urine specimens three days after treatment alblend support to T. glabrata being the most probable causative agent. The role of diabetes mellitus as an important pre-disposing factor to T. glabrata infection is well documented.l3-1 4 , 1 5 , l 6 Hyperglycaemia in diabetes mellitus has been demonstrated to inhibit phagocytosis by polymorpho-nuclear leukocytes.' Acidosis in these patients may further contribute to enhanced fungal dissemination into deeper tissues.I8 Ahearn et al.I3 recovered T. glabratu from 45 out of 1013 urine specimens and found that nine of the patients had diabetes mellitus.
58
TAN ET AL.
Speller14 reported two diabetic patients with T. glubrata urinary tract infections. The yeast was recovered from mid-stream urine of one patient for a continuous period of six months. No bacteria were isolated from all the specimens. Guze and Haley16 demonstrated T. glabrara in seven patients with urinary tract infections. Four of them were diabetics. Edebo and Spetz15 also reported a case of urinary tract infection caused by T glubruta in a diabetic patient who was subsequently treated by increasing the pH of the urine with sodium citrate. Treatment of patients with fungal urinary tract infections is often difficult." Before the advent of 5-fluorocytosine, most of the patients with urinary tract infections caused by yeasts were given intravenous infusions of amphotericin B.19 In T. glabratu infections, amphotericin B has been found to be most active in in uitro studies.20 However, it is well known that amphotericin B is highly toxic and has to be administered intravenously.21 Some authorities recommend bladder irrigation with amphotericin B in clearing lower urinary tract yeast infections, reserving the relatively toxic parenteral amphotericin B for cases with evidence of severe or disseminated tissue infection. 5-fluorocytosine is less toxic and is well absorbed orally.22 High serum and urine levels can be obtained in patients with normal renal function as well as those with moderate to severe renal impairment. were the first workers to Grunberg et employ 5-fluorocytosine in treating experimental mouse candidiasis. Since then, it has been the drug of choice in treating mycotic infections caused by Candida, Cryptococcus and Tordopsis species.14. 2 4 , 2 5 , 2 6 Unfortunately, strains of T. glubrata resistant to 5-fluorocytosine have occasionally emerged during in zlitro testing.22 Steer et al.27 reported two cases of chronic pyelonephritis caused by T. glubrata in two diabetic patients who failed to respond to 5fluorocytosine. They suggested that the administration of 5-fluorocytosine should be carefully monitored in patients during treatment. A daily dosage of 100-150 mg/kg body weight has been found adequate in treating Candida and Torulopsis infection^.'^ However, this dosage must be reduced in patients with moderate
VOL.
7,
NO.
1
renal impairment. In those with severe renal impairment, monitoring of plasma concentrations is essential. In addition, in zlitro sensitivity testing of 7'. glabruta to 5-fluorocytosine should always be carried out, in view of its likely resistance to the drug. Our findings together with the cases reported by other workers", 14, 2 0 , 27 strongly suggest that the frequency of urinary tract infections caused by T. glubrata could be higher than was previously suspected by clinical microbiologists. Greater awareness of the biochemical and morphological characteristics of T. glabraru and of its opportunistic pathogenicity in compromised hosts may enhance recognition of T. glabrata from clinical specimens. ,
Acknowledgements
We are indebted to Dr. D. W. R. MacKenzie of the Mycological Laboratory, London School of Hygiene and Tropical Medicine, England for confirming our 2'. gluhrutu isolates.
References 1. TAN,R J . S . , LIM. E W . and T s i . H R (1976): A survey ofurinary tract infections in Singapore-a 3 year study (In preparation.) 2. SILVA-HUTNER, M. and COOPER. B. H. (1974): Medically important yeasts. In: Munual of Clinxul Microbiology, ed. Lennette, E. H., Spaulding, E H. and Truant, J. P., 2nd. Edition, Amer. Soc. Microbiol, U S A . , p 491 3 SAhFoRn, J P. (1975). Urinary tract symptoms and infections, Ann. Rev. Med. 26, 485. 4. ~OCKlWA-l
