Fungi Flashcards
A cave-going hiker in Kansas presents with pulmonary symptoms such as pneumonia and lung lesions on X ray. The infection appears to have gone systemic and patient has hepatosplenomegaly and fibrotic calcification in the liver/spleen. KOH preo shows macrophages with ovoid bodies. What is the most likely infectious agent?
Histoplasma capsulatum
Patient from Michigan presents with symptoms resembling local pneumonia. X ray shows haziness due to alveolar infiltrate. Disseminated infection appears to be affecting the skin and bone. KOH prep shows broad based yeast budding. What is the most likely infectious agent?
Blastoomycosis dermatitidis
A patient from California presents with acute pneumonia, fever, sweats, and arthralgias. X ray is almost unremarkable but might have some small cavities/nodules. Patient claims there was an earthquake and following dust clouds that he was caught in. What is the most likely infectious agent?
Coccidioides immitis
A patient from Brazil area presents with cervical and upper lymphadenopathy. His lungs show granulomas on X ray and there are mucocutaneous ulcers in his gums with ragged borders. KOH prep/histology shows multiple buds that radiate out from a central vacuole, resembling a “Captains wheel”. What is the most likely infectious agent?
Paracoccidiodes brasiliensis
19 year old Pt comes in with ring shaped, pruritic lesions in his groin area which can be itchy. Hyphae are seen on KOH prep of the skin. The Pt admits to being active on many sports teams. What is the most likely infectious agent? Name the special test used to differentiate a particular one of these agents.
a Dermatophyte (Trichyphyton, Epidermophyton, or Microsporum) --> these cause Ringworm --Example in question: Tinea cruris (Jock Itch)
Microsporum can be specifically diagnosed with a Woods Lamp
A 20 year old female presents with ulcers along one side of her forearm. She says it started with one ulcer and then grew up her arm. Pt admits to being a caretaker of a home and gardens a lot. Culture shows cigar shaped budding yeast. What is the most likely infectious agent?
Sporothrix schenckii –> causes Sporotrichosis (Rose Gardener’s Disease)
25 year old male presents with white patches in the mouth that can be scraped off. Lab tests show a catalase positive organism and hyphae that grow on KOH prep. What is the most likely infectious agent? What form of this can be used as an AIDS-defining illness?
Candida albicans –> causes thrush / candidiasis
Candidal esophatitis is an AIDS-defining illness
This fungi is catalase positive with acute angle branching. It can cause an allergic reaction with wheezing, fever, & migratory pulmonary infiltrate or fungas balls associated with pre-formed lung cavities. What is the most likely infectious agent?
Aspergillus fumigatus
This organism produces aflatoxins, a highly carcinogenic agent known for causing hepatocellular carcinoma
Aspergillus flavus
50 year old man with leukemia presents with fever, cough, hemoptysis, kidney failure, endocarditis, & ring-enhancing lesions in the brain. He had TB in the past. KOH prep shows acute angle sepatation and conidiophores with fruiting bodies. What is the most likely infectious agent?
Aspergillus fumigatus
A 32 year old HIV+ man who manages a pigeon coop presents with cough, dyspnea, fever, and neurological symptoms resembling meningitis. India ink stain of CSF shows capsules that look like “halos” and a Latex Agglutination test is positive. His brain on gross pathology looks like it has “soap bubble” appearance due to lesions in gray matter. What is the most likely infectious agent?
Cryptococcus neoformans
-#1 cause of fungal meningitis
A 45 year old diabetic presents with tissue necrosis of the face, concentrated around the nose and eyes. KOH prep shows hyphae that are nonseptate and branch at wide, 90% angles. What is the most likely infectious agent?
Mucor
An elderly HIV+ patient presents with pneumonia-like symptoms like non-productive cough, dyspnea, and fever. X ray shows ground glass appearance. His CD4 count is less than 200. A Methamine silver stain is performed on a BAL/Bronchoalveolar lavage sample and shows disc-shaped ovoid yeast. What is the most likely infectious agent?
Pneumocystis jiroveci
