Introduction
Urinary candidiasis is a frequent nosocomial fungal infection around the globe. Candida species and Candida albicans are the most opportunistic pathogenic fungi leading to nosocomial urinary tract infections.
Candida albicans and non-Candida albicans candida are significant components of the normal microbial flora of the oral cavity, vagina, and alimentary canal in a wide range of healthy individuals. These species colonize the external parts of the urethral openings in healthy and premenopausal women. Immunosuppression causes an imbalance in the non-Candida albicans candida, C.albicans, and other flora. During this, the commensal yeasts of Candida may convert into opportunistic pathogenic microorganisms causing candidal urinary tract infections in the host.
What Are the Predisposing Factors for Urinary Candidiasis?
The predisposing factors include:
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Age.
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Gender.
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An extended period of antibiotic consumption.
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Genetic inheritance.
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Sexual activity of the individual.
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Immunosuppression.
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AIDS (acquired immunodeficiency syndrome).
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Pregnancy.
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Surgeries.
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Hospitalization.
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Indwelling medical devices such as prostheses or catheters.
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Low-level individual hygiene.
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Social behaviors.
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Unsuitable air conditioning.
When Candida albicans and non-Candida albicans Candida are detected in urine, candiduria is seen in both symptomatic and asymptomatic urinary tract infections. Urinary candidiasis has a high rate of morbidity and a low mortality rate.
Candida Albicans and Virulence Factors:
Candida albicans is a diploid dimorphic fungus and causes systemic candidiasis and fungal nosocomial urinary tract infections throughout the globe. Dimorphic fungi have shape flexibility which helps in switching yeast and filamentous forms. Candida albicans have a pathogenic mechanism of invasion, adhesion, discharging hydrolytic enzymes, stereotropism, and biofilm formation.
Candida Albicans and Polymorphism:
Candida albicans help in fungal infection and colonization.
The three types of Candida albicans include:
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Spheroid.
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Ovoid shape of single-celled budding yeast.
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Loose septate pseudohyphae with an elongated ellipsoid appearance of the hyphae.
Studies have shown that yeast cells and true hyphae contribute to urinary tract infections and candidiasis. The pseudohyphal form of Candida albicans is called a switch construction of the fungus in vivo conditions. The invasive type of fungus is the filamentous type of Candida albicans seen in solid tissues such as kidneys capable of producing proteases.
How Do Individuals Acquire Urinary Candidiasis?
Yeast growth is common in the vagina for various reasons and is commonly seen in dark and moist areas. Nylon undergarments, tight-fitting clothes, and skin folds provide a suitable environment for yeast growth. Yeast also proliferates when the normal flora is disrupted or when there are hormone fluctuations, usually seen in women on birth control pills or during pregnancy.
What Is Candiduria?
Candiduria is classified into symptomatic and asymptomatic forms. Symptomatic candiduria is seen in individuals with cystitis, prostatitis, epididymo orchatitis, renal candidiasis, and pyelonephritis. Candida albicans are often the causative organisms of candiduria compared to other 200 species of candida. Catheterization is a significant risk factor for candiduria in individuals admitted to the intensive care unit. The prevalence is higher in ICU-admitted individuals.
The three most common species of Candida are:
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Candida albicans.
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Candida glabrata.
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Candida tropicalis.
Individuals with candiduria do not show any clinical demonstrations or abnormalities.
Candida Cystitis and Pyelonephritis:
The invasion may also affect the urinary bladder, and the invasion of Candida species can cause candiduria. Candida cystitis is recognized by symptoms such as dysuria, high urine frequency, and hematuria. Candida pyelonephritis, if left untreated, may lead to sepsis and candiduria.
Candidal Balanitis and Vulvovaginal Candidiasis:
Candidal balanitis is a sexually transmitted disease; most of the time, both partners are affected. Candidal balanitis usually affects men, and vulvovaginal candidiasis affects women. Vulvovaginal candidiasis affects almost 75 % of women and can be easily treated. These diseases correspond with sexual activities, individual hygiene, and social behaviors.
It is commonly seen in Brazil, the USA, Northeast Africa, and Australia. Some studies have reported a higher incidence of vulvovaginal candidiasis in older women, and the species affecting it is Candida glabrata. There has been an increase in antifungal drug-resistant strains over time. Therefore it is mandatory to control the prevalence of the infection.
How Is Urinary Candidiasis Diagnosed?
Before the diagnostic procedure, it is essential to check if the urine sample is infected or contaminated. There are no rapid tests for detecting urinary candidiasis; however, it is a step-by-step approach for differential urinary candidiasis. If the urine culture results are positive, then the tests are repeated to ensure accuracy.
A 103 to 105 CFU per ml provides confirmation for candiduria. If the individual is catheterized, then the catheter should be cultured. In asymptomatic urinary candidiasis, the treatment is paralleled with the diagnosis. Antifungal drugs like Fluconazole must be administered if the individual does not respond to antibiotics. Vaginal or urine samples are used for the diagnosis of urinary candidiasis. Clinical manifestations help in providing differentiating upper and lower urinary tract candidiasis.
What Is the Treatment of Urinary Candidiasis?
Treatment is done with oral and topical antifungal drugs that are commercially available. Depending on the type of infection, such as cystitis, candiduria, pyelonephritis, vulvovaginal candidiasis, and candidal balanitis may have different antifungal medications. Azole helps in the inhibition of lanosterol 14-β-demethylase activity.
The enzyme helps in the destruction of fungal cell membranes. Candiduria is treated based on microscopic findings and culture results. Individuals with high risks are administered oral Fluconazole. If the individual is resistant to Fluconazole, they are administered Amphotericin B. In asymptomatic cases, Amphotericin B may be combined with Flucytosine.
Conclusion
Urinary candidiasis is the most common fungal infection, and Candida albicans is the causative agent. Treatment involves antifungal therapy, and there is a risk of developing resistance to drugs. Early detection can avoid complications.
