Strain relatedness in persistent and recurrent candiduria.
OBJECTIVE
We assessed the value of determining strain relatedness in differentiating persistent from recurrent candiduria.


METHODS
Prospective monitoring of patients with candiduria (10(4) or greater colony forming units per ml.) during a 5-month period. All patients with persistent or recurrent infection after documented clearance were selected. Pair isolates were typed using restriction endonuclease analysis of genomic deoxyribonucleic acid with SfiI. Isolates were considered related if all deoxyribonucleic acid bands matched.


RESULTS
We encountered 22 and 5 patients with persistent and recurrent infection, respectively. The isolates were recovered 1 to 140 days apart (21.56 +/- 28.97). Most patients were women (85.2%) with a mean age of 66.41 +/- 18.11 years. Risk factors included antibiotics (100%), indwelling catheter (88.9%) and diabetes mellitus (40.7%). Of 15 individuals who received antifungal therapy candiduria persisted in 10 and resolved but recurred within 4 to 26 days (13.00 +/- 9.08) after treatment in 5. Candida albicans accounted for 34 of 58 isolates (58.6%), and it was mixed with other species in 4 cultures. Paired strains were genetically identical in 26 of 27 patients. Strain persistence was documented in 21 of 22 cases with persistent infection and in all 5 patients with recurrent disease.


CONCLUSIONS
These findings show that strain persistence is exceedingly frequent in candiduria. These results imply that determining strain relatedness of Candida urinary isolates may not be reliable in differentiating persistent from recurrent infection.
Khatib
R
R
Department of Medicine, St. John Hospital and Medical Center, Detroit, Michigan, USA.
Ayeni
O
O
Riederer
K M
KM
Briski
L E
LE
Wilson
F M
FM
D000368:Aged; D002175:Candida / Q000235:genetics; D002177:Candidiasis / Q000382:microbiology* / Q000652:urine*; D002908:Chronic Disease; D004271:DNA, Fungal; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors
D004271:DNA, Fungal