Detection of Candida casts in experimental renal candidiasis: implications for the diagnosis and pathogenesis of upper urinary tract infection.
ABSTRACT The distinction between upper versus lower urinary tract infection in patients with candiduria is a commonly encountered and therapeutically important diagnostic dilemma. Candida casts have been reported in the urine of several individual case reports of human renal candidiasis. The specificity of Candida casts would identify unequivocally a patient with upper urinary tract disease. Little is known, however, about the sensitivity and the formation of Candida casts. We therefore studied the diagnostic yield, methods for detection and pathogenesis of Candida cast formation in serially collected urine specimens from immunologically intact and granulocytopenic rabbit models of haematogenous disseminated candidiasis. Refractile blastoconidia and pseudohyphae of Candida encased in the granular matrix were seen on wet mounts while Candida stained a brilliant red in the fuschia pink tubular matrix on periodic acid Schiff (PAS) stained cytopathology filters. Among 24 rabbits with disseminated candidiasis, 11 (46%) had Candida casts detectable by wet mount and PAS-stained urine filters in comparison to none of 10 non-infected immunologically normal controls (P = 0.014). Fifteen (70%) of 21 episodes of Candida casts were detected within the first 3 days of infection, indicating possible utility in the early diagnosis of renal candidiasis. No Candida casts were detected in the urine of granulocytopenic rabbits, possibly due to the rapid destruction of tubules and abrogation of cast formation. This absence of detectable Candida in eight infected granulocytopenic rabbits differed significantly from that of 24 non-granulocytopenic infected rabbits, in which Candida casts were detected in 11 (46%) (P = 0.029). Candida cast formation occurred predominantly in the cortex. Histopathological examination demonstrated invasion of Candida into the glomerular tufts and peritubular capillaries, followed by development of Candida casts in the proximal and distal tubules, respectively. Detection of renal Candida casts may be a useful diagnostic marker in distinguishing upper versus lower urinary tract candidiasis.
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ABSTRACT: Invasive fungal infections are a major cause of morbidity and mortality in immunocompromised patients. Because the etiologic agents of these infections are abundant in nature, their isolation from biopsy material or sterile body fluids is needed to document infection. This review evaluates and discusses different human body fluids used to diagnose fungal infections.BioMed research international. 01/2013; 2013:698325.
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ABSTRACT: Invasive fungal diseases (IFDs) continue to cause considerable morbidity and mortality in patients with haematological malignancy. Diagnosis of IFD is difficult, with the sensitivity of the gold standard tests (culture and histopathology) often reported to be low, which may at least in part be due to sub-optimal sampling or subsequent handling in the routine microbiological laboratory. Therefore, a working group of the European Conference in Infections in Leukaemia was convened in 2009 with the task of reviewing the classical diagnostic procedures and providing recommendations for their optimal use. The recommendations were presented and approved at the ECIL-3 conference in September 2009. Although new serological and molecular tests are examined in separate papers, this review focuses on sample types, microscopy and culture procedures, antifungal susceptibility testing and imaging. The performance and limitations of these procedures are discussed and recommendations are provided on when and how to use them and how to interpret the results.Bone marrow transplantation 01/2012; 47(8):1030-45. · 3.00 Impact Factor
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ABSTRACT: The purpose of this investigation was to assess the prevalence of upper urinary tract involvement in patients with candiduria by means of (111)indium-oxine-labeled leukocyte scintigraphy. An observational cohort study of patients with confirmed candiduria was conducted in an acute-care teaching hospital in Spain from March 2006 through February 2009. An (111)In-labeled leukocyte scan was performed in order to assess the upper urinary tract involvement. A series of non-matched patients without candiduria nor bacteriuria undergoing scintigraphy to exclude infections in other sites than the urinary tract was also studied. Demographics, baseline illness, and clinical data were recorded. Candiduria was detected in 428 patients, and scintigraphy was performed in 35 of these patients. Twenty-nine patients without candiduria nor bacteriuria were also studied. Positive renal scintigraphy was documented in 24 (68%) patients with confirmed candiduria and in 3 (10%) patients without candiduria (p < 0.005). Renal uptake was not associated with a higher mortality nor with re-admissions. Subclinical pyelonephritis could be more frequent in patients with candiduria than it has been previously considered.European Journal of Clinical Microbiology 06/2011; 31(3):237-42. · 3.02 Impact Factor