Fungal Infections

javireva's version from 2015-11-29 05:36

Section 1

Question Answer
Explain 4 important functions regarding fungal structure1. sterols in cell membrane 2. no structures for locomotion 3. 2 morphological forms (yeast and mold) 4. yeast is round, mold is composed of filaments (hyphae)
Methods of reproduction:fission, budding, fragmentation of hyphae, spore formation by mold
Name superficial fungal infectionpityriasis versicolor
Name cutaneous fungal infectionsTineas or ringworms or dermatophytes
Name subcutaneous fungal infectionsporotichosis- rose handlers disease

Section 2

Question Answer
Pityriasis VersicolorMalassezia furfur
Diagnosis of pityriasis versicolormicroscopic exam- 10% KOH + calcofluor whit
Only contagious fungal infectionTineas
Tinea corporisnon hairy body parts
tinea capitis scalp
tinea pedisathletes foot
tinea barbaebeard
tinea cruris jock itch
tinea unguiumnails
Treatment for tinea corporismiconazole, clotrimazole, for 2-4 weeks and 1-2 weeks after it clears
Treatment for tinea capitis1-2 months oral and topical needed
Diagnosis of tinea capitisInfected hair fluorese in light- woods lamp
Rose handlers diseaseSporotrichosis
Characteristic lesion of sporotrichosisinitial lesion usually on extremity, multiple lesions in a line, develope along lymphatic tracts, few systemic s/s
Diagnosis of sporotrichosisculture of infected pus or tissue
Treatment for sporotrichosisrequires oral treatment- itraconazole for up to 6 months


Question Answer
4 main systemic mycoseshistoplasmosis, coccidiomycosis, blastomycosis, paracoccidiomycosis
Characteristics of systemic mycosesdimorphic (filamentous in nature, yeast at body temp), lung is primary focus of infection
Ohio, mississippi riverHistoplasmosis
Southwest U.S., mexico, south americaCoccidioidomycosis
Mississippi River basin, near great lakesBlastomycosis
No capsuleHistoplasma capsulatum
Bird, bad droppings, chicken coops, attics, barnsHistoplasmosis
80% of people in Ohio, Mississippi River Valley have pos skin testHistoplasmosis
Describe symptoms of systemic histoplasmosisfever, NS, WL, hepslen megaly,
Detect Ag in urine or blood for dxHistoplasmosis
Valley FeverCoccidiodomycosis
Inhaled in disturbed dust (construction, archeologists)Coccidiodomycosis
IgM response to recent infectionCocccidioidomycosis
Treatment and length for coccidioidomycosisamphotercin b
Pathogen for CoccidioidomycosisCoccidioides immitis
Pathogen for BlastomycosisBlastomyces dermatidis
10 times more common in dogs than peopleBlastomycosis
Chronic, painless skin lesionBlastomycosis
Very large, broad flat connectionsBlastomycosis
Diagnosis of blastomycosisConfirmation by culture necessary, serology is not reliable
Treatment for Blastomycosis - disseminatedAmphotericin B, Itraconazole,


Question Answer
Characteristic of opportunistic funginone are dimorphic
Most common opportunistic infection in HIV patientsPneumocystis jiroveci PN
Diagnosed by bronchoalveolar lavage + xray (diff bilat infiltrates)Pneumocystis jiroveci PN
Explain treatment for PJPprophylaxis used for HIV with CD4 < 200 with TMP-SMX, pentamidine. Treatment for 21 days
Most common serious mycosis in humansCandidiasis
3rd most common isolate from bloodCandidiasis
4th most common cause of nosocomial infectionsCandidiasis
Treatment for superficial candidiasistopical nystatin, miconazole, clotrimazole
Treatment for thrushnystatin, clotrimazole
Mortality rate for dissiminated disease is 40-60%Candidiasis
Germ tube testCandidiasis
elongated ends- pseudohyphaeCandidiasis
Only encapsulated yeast of medical importanceCryptococcus
Soil and bird droppings (particularly pigeons)Cryptococcus
Hallmark infection in AIDS patientCryptococcus meningitis
Not dimorphic- starts with pulmonary infection by yeastsCryptococcus
More CNS issues than PNCryptococcus
Slow developingCryptococcus
India ink testCryptococcus
Latex agglutination testCryptococcus
What does the Latex agglutination test showdetects capsular material shed into body fluids- 90% sens
Treatment for crytococcusAmphotericin B, then oral fluconazole- AIDS require for life
Cost common group of fungi in environmentAspergillosis
2 fungi that are NOT found more in HIVAspergillosis and Zygomycosis
fungus ballAspergillosis
Diagnosis for aspergillosisBC are NOT reliable, direct exam for branching septate, fungus ball on xray
Treatment for Aspergillosissurgical resection- drugs dont penetrate fungus ball
Organisms invade BV, cause thrombosis, and necrosisZygomycosis
Fatal within 72h of definitive symptomsZygomycosis
broad, non septate, ballooned hyphaeZygomycosis
Treatment for zygomycosisamphotericin B, posaconazole- often not successful