Candidiasis

Basics

Description

Infection caused by species of the yeast, Candida; encompasses a spectrum of disease depending on host factors:

  • Mucosal infection: oral thrush, esophagitis, vaginitis
  • Cutaneous infection: diaper dermatitis, intertriginous dermatitis
  • Disseminated candidiasis: candidemia, hepatosplenic candidiasis, meningitis, endocarditis, endophthalmitis

Epidemiology

Incidence

  • Mucosal: Thrush occurs in ∼5% of normal newborns.
  • Disseminated: 3rd most common cause of bloodstream infection in hospitalized patients

Risk Factors

Immunocompromise (HIV, malignancy, neutropenia, transplant recipient, corticosteroid use), prematurity, burn injury, central venous catheter, parenteral nutrition, broad-spectrum antibiotic use

General Prevention

  • Sterilize bottle nipples and toys to prevent reinfection with oral candidiasis.
  • Avoid unnecessary broad-spectrum antibiotic use and limit duration when used.
  • Remove indwelling IV catheters as soon as possible and maintain sterility with line care.
  • Prophylaxis is indicated for some high-risk populations (preterm infants <750 g in high-incidence nurseries, neutropenic patients).

Etiology

  • 20% of patients have GI or respiratory tract colonization. Neonatal colonization is acquired from infected vaginal mucosa during birth. Incidence of colonization increases with age of the infant especially if exposed to antibiotics or poor hand washing. Colonization increases the risk of invasive infection.
  • Candida albicans is the most common species isolated in children; non-albicans species are increasing in incidence: Candida parapsilosis > Candida glabrata > Candida lusitaniae > Candida krusei > other.

Commonly Associated Conditions

Candida spp. may cause disease at any site.

  • Mucosal candidiasis
    • Oropharyngeal candidiasis (thrush) occurs in 5% of normal infants. In older children, it is associated with use of antibiotics, inhaled corticosteroids or immunosuppressive drugs, conditions of endocrine or immune dysfunction, and malignancy.
    • Perlèche (angular cheilosis) is characterized by fissuring, erythema, and pain at the corners of the mouth; more common in children who lick their lips frequently or have vitamin deficiencies
    • Esophageal candidiasis occurs in HIV-infected patients and those on immunosuppressive therapy; 30% have associated thrush.
  • Cutaneous candidiasis
    • Diaper dermatitis is most common during infancy because of predisposing factors found with diaper use—warm, moist environment. May co-occur with thrush.
    • Intertriginous candidiasis occurs in skinfolds where there are opposing skin surfaces; generally occurs in healthy patients with the risk factors of chronic moisture, recent antibiotic use, or obesity
  • Vaginal candidiasis: Oral contraceptives, antibiotics, pregnancy, corticosteroids, and immunodeficiency are predisposing conditions; classified as uncomplicated or complicated
    • Uncomplicated (90%): mild to moderate; sporadic; organism is C. albicans; normal host
    • Complicated (10%): presence of any one of the following factors defines a complicated infection: severe, recurrent (>4 episodes/year) infection by non-albicans Candida spp. or predisposing host factor (immunocompromised, diabetes mellitus [DM], etc.)
  • Congenital candidiasis: cutaneous infection acquired from infected amniotic fluid. Usually has an excellent prognosis.
  • Invasive candidiasis
    • Defined as candidemia and disseminated candidiasis (including hepatosplenic candidiasis). Candida from a blood culture should never be considered a contaminant.
    • Risk factors include prematurity, malignancy, immunodeficiency syndromes, DM, broad-spectrum antibiotic therapy, corticosteroids, chemotherapy, hyperalimentation, indwelling catheters, ICU stay, recent complex surgery, and stem cell or organ transplantation.
    • The most frequent sites of involvement are the GI tract, lungs, kidneys (pyelonephritis, mycetoma), liver, spleen, eyes, and brain (meningoencephalitis). Fungal sepsis may occur. Peritoneal, urinary tract, and cardiac valve candidal infections are most often related to instrumentation or catheterization in the immunocompromised host.
  • Chronic mucocutaneous candidiasis
    • Noninvasive infection of the skin, hair, mucous membranes, and nails
    • Typically seen in the 1st year of life, and almost all cases occur within the 1st decade
    • Caused by a T-cell defect resulting in decreased production of Candida-specific antibody. Patients lack a delayed-type hypersensitivity reaction to intradermal injection of candidal antigens. May be part of polyglandular autoimmune syndrome type 1.

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