161: Yeast Infections Flashcards
What are the common areas of involvement for Candida species in mucocutaneous candidiasis?
Common areas include: oral mucosa, lips, intertriginous zones, genital areas, skin and mucosal involvement.
Which Candida species are most commonly implicated in localized mucocutaneous candidiasis?
The most commonly implicated species include Candida albicans, Candida glabrata, Candida tropicalis, Candida krusei, Candida parapsilosis, and Candida dubliniensis.
What are the classic cutaneous findings associated with Candida infections?
Classic cutaneous findings include beefy-red patches and plaques with satellite papules and pustules, intertriginous areas, miliaria on occluded skin surfaces, pseudomembranous form in oropharyngeal mucosa, erythematous form in those with dentures, angular cheilitis, nipple candidiasis in breastfeeding women, and genital skin and mucosa involvement with itching and burning.
What is the classic clinical triad of candidemia?
The classic clinical triad of candidemia includes myalgia, rash, and fever.
What are the risk factors associated with onychomycosis caused by Candida?
Risk factors include moisture and occupational wet work, chronic exposure to water, use of the dominant hand, history of paronychia, and skin barrier breakdown due to dermatitis.
What is the significance of chronic mucocutaneous candidiasis?
It presents with erythematous plaques with overlying scale reminiscent of plaque psoriasis.
What is the role of Candida in chronic paronychia?
It can cause erythema of the proximal nailfold area with loss of the cuticle and skin breakdown.
What percentage of candidemia patients may experience myalgia?
25% of patients with candidemia.
What is the significance of myalgia, rash, and fever in a hospitalized patient with candidemia?
These findings suggest the classic clinical triad of candidemia. Empiric treatment should include echinocandins or fluconazole.
What are the typical characteristics of skin lesions in candidemia?
Typical skin lesions range from erythematous papules with central pallor or necrosis to erythematous nodules or plaques.
What are common sites of Candida colonization in healthy adults?
Common sites include skin, oropharyngeal, respiratory, gastrointestinal, and genital mucosa. Higher rates of carriage are observed in women and smokers.
What are the classic cutaneous findings of localized Candida infections?
Localized Candida infections typically present as beefy-red patches and plaques with satellite papules and pustules at the periphery.
Describe the clinical triad of candidemia and its implications for treatment.
The classic clinical triad includes myalgia, rash, and fever. Empiric treatment for presumptive invasive candidiasis is often initiated in hospitalized patients presenting with these symptoms.
What are the common non-cutaneous findings associated with candidemia?
Common non-cutaneous findings include myalgia, chorioretinitis, vitreitis, and endophthalmitis.
How does chronic mucocutaneous candidiasis present clinically?
It presents as erythematous plaques with an overlying scale, resembling plaque psoriasis.
What are the implications of Candida species in invasive candidiasis and candidemia?
While Candida albicans is the most common species, non-albicans species collectively account for the majority of invasive candidiasis and candidemia.
What are the common complications associated with candidemia?
Complications include multiorgan failure leading to septic shock, hematogenous dissemination to organs, and potential for painless retinal involvement resulting in permanent visual loss.
What are the risk factors for localized or superficial Candida infections?
Risk factors include extremes of age, diabetes, obesity, pregnancy, HIV/AIDS, use of broad-spectrum antibiotics, corticosteroids, and immunosuppressive medications.
What laboratory tests are used for the diagnosis of candidiasis?
Tests include swab culture from an intact pustule, tissue culture from biopsy specimens, and positive blood cultures.
What is the first-line management for cutaneous candidiasis?
First-line management includes topical imidazoles and nystatin topical, with oral antifungals for severe cases.
What are the clinical implications of the IL-17 pathway in Candida infections?
Defects in the IL-17 pathway can lead to increased susceptibility to chronic mucocutaneous candidiasis.
What is the prognosis for candidemia?
Candidemia has significant mortality, with rates exceeding 35% over 12 weeks in some studies.
What is the first-line treatment for oral candidiasis and its duration?
First-line treatment is Clotrimazole 10-mg troches taken 5 times daily or Miconazole 50-mg buccal tablets for 1 to 2 weeks.
What is the recommended treatment for Candida onychomycosis?
First-line treatment is Itraconazole given orally for a total minimum duration of 4 weeks for fingernails and 12 weeks for toenails.
What is the first-line treatment for Candida vulvovaginitis?
First-line treatment is topical Miconazole and Clotrimazole, with an alternative being oral Fluconazole.
What is the first-line treatment for chronic mucocutaneous candidiasis?
First-line treatment involves prolonged courses of oral imidazoles or triazoles.
What should be done for patients with disseminated candidiasis?
Patients should be managed with the assistance of an infectious disease specialist.
What are the diseases associated with Malassezia species?
Malassezia species are associated with diseases such as pityriasis versicolor and Malassezia folliculitis.
What is the first line treatment for oral candidiasis?
Clotrimazole 10-mg troches 5 times daily or miconazole 50-mg buccal tablets.
Duration is 1 to 2 weeks.
What is an alternative treatment for refractory oral candidiasis?
Itraconazole, posaconazole, voriconazole, and amphotericin B solutions and suspensions.
What is the recommended treatment for Candida onychomycosis?
Itraconazole given orally, with a total minimum duration of 4 weeks for fingernails and 12 weeks for toenails.
What adjunctive treatment can help prevent reinfection in oral candidiasis?
Denture disinfection using effervescent denture tablets or dilute bleach concentration of 1:32 or higher.
What is the first line treatment for chronic mucocutaneous candidiasis?
Prolonged courses of oral imidazoles or triazoles (voriconazole and posaconazole).
What should be done for patients with disseminated candidiasis?
They should be managed with the assistance of an infectious disease specialist.
What is the first line treatment for Candida vulvovaginitis?
Topical miconazole and clotrimazole.
What is the role of topical corticosteroids in chronic paronychia?
They help yield a higher cure rate than systemic antifungals.
What is the significance of Malassezia in skin infections?
Malassezia species can cause a variety of clinical presentations including pityriasis (tinea) versicolor and Malassezia folliculitis.
What is the recommended chronic suppressive therapy for recurrent oral candidiasis in a patient with HIV?
Chronic suppressive therapy involves fluconazole 150 mg orally three times weekly.
What additional diagnostic steps are recommended for a patient with candidemia and a positive blood culture?
Follow-up blood cultures and an ophthalmologic examination are recommended to monitor for complications such as endophthalmitis.
What is the primary insult leading to chronic paronychia, and what topical treatment has shown higher cure rates?
The primary insult is skin barrier breakdown from wet work and possible contact dermatitis. Topical corticosteroids have shown higher cure rates than systemic antifungals.
What alternative treatment can be considered for a patient with disseminated candidiasis resistant to azoles and echinocandins?
Lipid formulation amphotericin B.
What is the recommended duration of treatment with itraconazole for Candida onychomycosis?
A minimum of 4 weeks for fingernails and 12 weeks for toenails.
What alternative treatments might be required for a patient with chronic mucocutaneous candidiasis who develops resistance to triazoles?
Alternative treatments include echinocandins, liposomal amphotericin, or flucytosine.
What is the dosing regimen for severe or recurrent cases of Candida vulvovaginitis treated with oral fluconazole?
150 mg in 2-3 doses, 72 hours apart, and even longer for recurrent cases.
What is the first-line treatment for hemodynamically stable candidemia?
An echinocandin or fluconazole.
What is the rationale for using topical treatment as first-line therapy for Candida vulvovaginitis?
Topical treatment effectively targets localized infection with minimal systemic absorption.
What is the recommended initial treatment for a neutropenic patient with candidemia, and when can it be switched?
An empiric echinocandin, which can be switched to fluconazole once the patient is stable.
What is the mechanism of action of topical tacrolimus in chronic paronychia?
It acts as an immunomodulator, reducing inflammation.
What is the first-line treatment for Candida vulvovaginitis?
Topical miconazole and clotrimazole, with an alternative being oral fluconazole, usually 150 mg in a single dose.
What is the significance of resistance in the treatment of disseminated candidiasis?
Resistance to azoles and echinocandins is significant in non-Candida albicans species and in patients with prior exposure, necessitating alternative treatments.
What are the diseases associated with Malassezia species?
Pityriasis (tinea) versicolor and Malassezia folliculitis.
What are the common skin infections associated with Malassezia species in tropical climates?
Pityriasis versicolor and Malassezia folliculitis.
What role do Malassezia species play in internal infections?
They are frequently isolated from sinuses, urinary tract infections, meningitis, pneumonia, and nosocomial bloodstream infections.
What are the risk factors associated with Malassezia folliculitis and pityriasis versicolor?
Tropical climates, heavy sweating, immunosuppression, oral antibiotics, and corticosteroids.
How is pityriasis versicolor diagnosed?
Using dermoscopy, Wood lamp examination, KOH preparation, and staining.
What is the etiology of Malassezia infections?
Malassezia is normal flora of human skin, relying on hydrolysis of human host sebum triglycerides.
What are the cutaneous findings of pityriasis versicolor?
Asymptomatic to mildly pruritic patches and thin plaques with fine scale.
What distinguishes Malassezia folliculitis from acne vulgaris?
Malassezia folliculitis lacks comedones and tends to spare the centrofacial areas.
What are the common species of Malassezia associated with pityriasis versicolor?
Malassezia globosa.
What is the characteristic finding on KOH preparation for Malassezia folliculitis?
The ‘ziti and meatballs’ sign, showing short hyphae and yeast forms.
What is the role of Malassezia in seborrheic dermatitis?
Malassezia acts as an exacerbating factor rather than a true infection.
What is the expected finding under a Wood lamp for pityriasis versicolor?
Yellow-green fluorescence.
What is the mechanism behind hyperpigmentation in pityriasis versicolor?
Increased melanosomes and thickening of the stratum corneum.
What is the significance of azelaic acid in the context of Malassezia infections?
Azelaic acid inhibits tyrosinase, affecting melanin synthesis and can lead to hypopigmentation.
What organism is most likely responsible for a bloodstream infection in a preterm neonate receiving parenteral lipid infusions?
Malassezia pachydermatis.
What clinical feature can help differentiate Malassezia folliculitis from acne vulgaris?
Malassezia folliculitis lacks comedones.
What are the most frequently isolated species from the sinuses in chronic rhinosinusitis?
Malassezia restricta and Malassezia globosa.
What sample collection method is used for KOH preparation in Malassezia folliculitis?
A comedone extractor or needle is used to puncture an intact pustule.
What is the characteristic microscopic finding in KOH preparation for pityriasis versicolor?
The ‘ziti and meatballs’ sign.
What distinguishes Malassezia folliculitis from acne vulgaris?
It is characterized by follicularly based erythematous papules and pustules without comedones.
How does the colonization of Malassezia occur in infants?
By the age of 3 to 6 months, with earlier colonization associated with the length of NICU stays.
What are the clinical manifestations of pityriasis versicolor?
Asymptomatic to mildly pruritic patches and thin plaques with fine scale.
What diagnostic tools are used for pityriasis versicolor?
Diagnostic tools include dermoscopy to highlight fine scaling, Wood lamp examination showing yellow-green fluorescence, and KOH preparation revealing the ‘ziti and meatballs’ sign with short hyphae and yeast forms.
What is the significance of azelaic acid in the pathogenesis of pityriasis versicolor?
Azelaic acid, produced during the transition of Malassezia to its pathogenic mycelial form, inhibits tyrosinase, the enzyme responsible for melanin synthesis, leading to hypopigmentation especially in darker-skinned individuals.
What laboratory testing challenges are associated with culturing Malassezia species?
Culturing Malassezia is challenging due to its lipid requirement, necessitating the addition of a layer of olive oil and the use of special growth media such as modified Dixon. Culture is not typically used to confirm Malassezia infections.
What histopathological findings are associated with pityriasis versicolor and Malassezia folliculitis?
Histopathological findings include Malassezia yeast forms within the stratum corneum for pityriasis versicolor, and within dilated infundibula of plugged follicles in Malassezia folliculitis, often accompanied by perivascular lymphocytes, histiocytes, and neutrophils.
What is the first line of treatment for Pityriasis versicolor?
The first line of treatment for Pityriasis versicolor includes:
- Topical shampoos (pyrithione zinc or selenium sulfide)
- Propylene glycol in aqueous solution
- Azole antifungal creams (ketoconazole is the most studied).
What are the recommended treatments for Malassezia folliculitis?
For Malassezia folliculitis, the treatment options include:
- Monotherapy with topical antifungals (less reliable efficacy)
- Addition of keratolytics like propylene glycol may improve efficacy
- Systemic treatment may be required, with itraconazole 200 mg daily for 1 to 3 weeks being the best studied.
What are the risk factors for recurrence of superficial Malassezia infections?
Risk factors for recurrence of superficial Malassezia infections include:
- Strong risk factors such as preterm neonates and immunosuppressed patients
- Parenteral lipid infusions, which increase the risk of disseminated infection.
Why is ketoconazole not recommended for the treatment of Malassezia infections?
Ketoconazole is not recommended for the treatment of Malassezia infections due to the risk of liver damage and adrenal dysfunction.
What is the prognosis for superficial Malassezia infections?
The prognosis for superficial Malassezia infections is generally good, as most will respond readily to antifungal treatment. However, recurrence is common, particularly in patients with strong risk factors.
What is the recommended treatment for extensive or refractory Pityriasis versicolor?
Oral antifungal treatment with fluconazole or itraconazole.
What is the role of propylene glycol in the treatment of Malassezia folliculitis?
Propylene glycol acts as a keratolytic, improving the efficacy of antifungal treatment in Malassezia folliculitis.
What is the best-studied systemic treatment for Malassezia folliculitis?
Itraconazole 200 mg daily for 1 to 3 weeks.
What is the typical duration of itraconazole treatment for Malassezia folliculitis?
The typical duration of itraconazole treatment for Malassezia folliculitis is 1 to 3 weeks.
What is the recommended prophylactic dosing regimen for itraconazole?
The recommended prophylactic dosing regimen for itraconazole is 200 mg BID for 1 day per month for 6 months.
What are the first-line treatments for Pityriasis versicolor and their formulations?
The first-line treatments for Pityriasis versicolor include:
-
Topical shampoos:
- Pyrithione zinc
- Selenium sulfide
-
Topical antifungal creams:
- Azole antifungal creams (ketoconazole is the most studied)
- Propylene glycol in aqueous solution.
What are the long-term management strategies for preventing recurrence of Pityriasis versicolor?
Long-term management strategies for preventing recurrence of Pityriasis versicolor include:
-
Prophylactic long-term treatment in some patients:
- Periodic topical selenium sulfide shampoo
- Ketoconazole 2% shampoo
- Itraconazole 200 mg BID, 1 day/month for 6 months.
What factors increase the risk of disseminated Malassezia infection in patients?
Factors that increase the risk of disseminated Malassezia infection include:
- Preterm neonates
- Immunosuppressed patients
- Parenteral lipid infusions
What is the efficacy of monotherapy with topical antifungals for Malassezia folliculitis?
Monotherapy with topical antifungals for Malassezia folliculitis has less reliable efficacy. To improve treatment outcomes, the addition of a keratolytic agent like propylene glycol may enhance the efficacy of the antifungal treatment.
