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30 Cards in this Set
- Front
- Back
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Endemic Mycoses
• Endemic mycoses of North America (3) • Other endemic mycoses (2) |
• Endemic mycoses of North America (usually inhaled, diagnosis depends on location)
– Histoplasmosis – Blastomycosis – Coccidioidomycosis • Other endemic mycoses – Penicilliosis – Paracoccidioidomycosis |
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Histoplasmosis – Microbiology
Histoplasma capsulatum •________ fungus – < 35°C – _____ • micro- and macroconidia - > 37°C – ______ • in tissue: small (2-4μm), ellipsoidal |
• Histoplasma capsulatum
• Dimorphic fungus – <35°C – mold • micro- and macroconidia – > 37°C – yeast• in tissue: small (2-4μm), ellipsoidal |
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Histoplasmosis - Epidemiology
• Present in much of the US – Most cases in _____ and ______ river valleys Global Distribution? • Associated with____ and ___ guano – soil with high ________ content • Local outbreaks associated with? (3) What else is associated with bird droppings? |
• Present in much of the US
– Most cases in Mississippi and Ohio river valleys • Exists worldwide – Foci of high reactivity in southern Mexico, Indonesia, Philippines, Turkey • Associated with bird and bat guano – soil with high nitrogen content • Local outbreaks associated with caves, bird roosts, construction Cryptococcus also associated with bird droppings |
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Histoplasmosis – Pathophysiology
• _________ disease • Similar to __ • Microconidia (1-5μm) easily dislodged with _______ – are _________ • Microconidia are _______ • Phagocytized by? • Divide within? |
• inhalational disease
• Similar to TB • Microconidia (1-5μm) easily dislodged with dehydration – are aerosolized • Microconidia are inhaled • Phagocytized by alveolar macrophages • Divide within macrophages and disseminate |
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Acute Histoplasmosis
Symptoms? Presentation? Therapy? • Most common cause in the U.S. of _______ ___________in lung, liver and spleen |
• May be asymptomatic
• May present as mild flulike illness • Self-limited (no therapy) • Most common cause in the U.S. of calcified granulomas in lung, liver and spleen |
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Progressive Disseminated
Histoplasmosis (PDH) • Acute PDH – Affects which patients? • Subacute and chronic PDH – Affects which patients? – Presentation? – _________ (may be confused with malignancy) – Liver/spleen? – CBC shows? (usually not severe) |
• Acute PDH
– HIV and profoundly immunocompromised • Subacute and chronic PDH – Non-immunosuppresed patients – Malaise, weight loss, fever – Oral ulcers (may be confused with malignancy) – Hepatosplenomegaly – May have bone marrow involvement with low white blood cells or anemia (usually not severe) |
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When you see chronic oral lesions, think:
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HISTO!
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Histoplasmosis - Diagnosis
• Direct microscopy – __________ • Culture – _________ – _____________ (HIV) • ___________ skin test • Serology (2) • Antigen testing (test which fluids?) |
• Direct microscopy
– Silver stain • Culture – Tissue – Isolator tube culture (HIV) • Histoplasmin skin test • Serology (measures antiBODY) – Complement fixation – Immunodiffusion • Antigen testing (measures antiGEN) – Urine and serum - usually only positive in HIV patients - very specific; rules in disease; negative antigen does NOT rule it out |
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Histoplasmosis - Therapy
What do you use for severe illness? • __________ for less severe illness and follow-up therapy (200 mg qD or BID) • Duration of therapy? |
• Amphotericin B for severe illness
• Itraconazole for less severe illness and follow-up therapy (200 mg qD or BID) • Prolonged therapy the rule • Voriconazole and posaconazole have activity, but there is very little clinical experience |
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Histoplasmosis: Other Disease
• _______________ – Can look like TB – Usually in patients with ________ – Dx - culture or serology – Tx - ____________ • ______________ – Chronic _____________ – Dx - CSF serology or culture – Tx - ____________ followed by prolonged ____________ |
• Cavitary pulmonary disease
– Can look like TB – Usually in patients with emphysema – Dx - culture or serology – Tx - itraconazole • Aseptic meningitis – Chronic lymphocytic meningitis – Dx - CSF serology or culture – Tx - amphotericin B followed by prolonged fluconazole |
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Which class of drugs have no effect on histoplasmosis?
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Echinicandins (from previous lecture from this dude)
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Mediastinal fibrosis
• aka _______________ • Exuberant immune response to what organism? • Characterized by deposition of _______, where? – Encroaches on _______?. • Treatment? |
• aka fibrosing mediastinitis
• Exuberant immune response to H. capsulatum • Deposition of fibrotic tissue in mediastinum – Encroaches on airway, esophagus, SVC, et al. • Drug therapy probably of little utility |
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Blastomycosis - Microbiology
Type of fungus? What is very characteristic of blasto? |
• Blastomyces dermatitidis
• Dimorphic fungus • Tissue – broad based budding (VERY characteristic of blasto) |
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Blastomycosis - Epidemiology
• Endemic in _______ and _______ U.S. – present in other areas:? • Cases associated with _______ _________ especially in wooded areas along waterways • Found in soil? |
• Endemic in Central and Eastern U.S.
– present in other areas: India, Africa, S. America • Cases associated with outdoor activity, especially in wooded areas along waterways • Isolated from soil only sporadically (rare) |
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Blastomycosis - Pathophysiology
• Portal of entry is the _______ • Initial symptoms? – Incubation __-__ days |
• Portal of entry is the lungs
• Initial infection usually asymptomatic – Incubation 30-45 days |
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Blastomycosis – Disease
(4)? |
Blasto - focal, not diffuse, Lungs, skin, and bone think Blasto
• Pulmonary • Cutaneous • Bone and joint • CNS |
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Blastomycosis - Disease
• Pulmonary - focal or diffuse? • Cutaneous - acute/chronic? lesions characterized by? • Bone and joint - focal/diffuse? • CNS - what kind of brain disease does it cause? |
• Pulmonary
– Usually focal lesions • Cutaneous – Chronic non-healing lesions that ulcerate • Bone and Joint – Invasive/destructive focal lesions • Central nervous system – Aseptic meningitis |
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Blastomycosis – Diagnosis
? |
• Biopsy
• Culture • Serology – EIA – Titer >1:16 – Complement Fixation not reliable • Urine antigen (just like histo antigen) there is cross reactivity between these tests - they are very specific - if positive, you have one or the other, but can't specify which with certainty |
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Blastomycosis - Therapy
Standard of therapy? Severe illness? |
• Itraconazole (200-400 mg/day)
• Amphotericin B for CNS or severe disease – Fluconazole 800 mg/day for CNS disease if can’t tolerate AmB • Voriconazole and posaconazole have activity, but there is very little clinical experience |
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Coccidioidomycosis - Microbiology
– most isolates outside of _______ (state) • _______ fungus (type) • _________ are infectious particles that these fungi possess • Tissue – characteristic features? |
– most isolates outside of California
• Dimorphic fungus • Arthroconidia are infectious particles • Tissue – spherules with endospores |
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Coccidioidomycosis - Epidemiology
• Endemic in soil in _______ (region) U.S. – Most cases in ___ (dry/wet?) months following ______ ______ • Significant differences in risk of dissemination – ______ >>> _______ descent > _______descent |
• Endemic in soil in Southwestern U.S.
– Most cases in dry months following winter rains • Significant differences in risk of dissemination – Filipino >>> African descent > European descent |
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Acute Coccidioidomycosis
Symptoms? CXR shows? Diagnosis made by? (just like it is with others) |
• 50-65% asymptomatic
• Non-specific respiratory illness • Infiltrates or hilar adenopathy on CXR • Diagnosis - changes in serology |
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Acute Coccidioidomycosis -Therapy
Treat who? Drug of choice? |
• Controversial - some treat everyone
• Recommended for patients at high risk for dissemination – HIV – Organ transplant – Pregnancy – ? Filipino or African descent • Reasonable for patients with severe or prolonged symptoms • Itraconazole probably drug of choice |
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Chronic Coccidioidomycosis
Presentation |
• Chronic fibrotic pneumonia
• Extrapulmonary disease – Bone and joint – Cutaneous – Meniningitis |
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Fibrotic lung disease + aseptic meningitis = think?
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coccidioidomycosis
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Coccidioidomycosis – Diagnosis
Serology: titer indicates what? (except when ______?) |
• Biopsy
• Culture • Serology – CF titer ≥1:32 indicates secondary disease – Titer indicates severity (except meningitis) – Also ID and tube precipitin tests available |
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Coccidioidomycosis – Treatment
For severe disease? What is NOT for CNS disease? What is better than fluconazole for bone & joint Duration of therapy? |
• Amphotericin B initial therapy for severe disease
• Itraconazole 200 mg BID – Not for CNS disease – Better than fluconazole for bone & joint • Fluconazole 400 mg/day (has more activity against cocci than the others) • Voriconazole and posaconazole have activity, but there is very little clinical experience • Prolonged therapy |
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Penicilliosis - Epidemiology
- Type of fungus? - Endemic area - ? - Seen in what population? |
• Dimorphic fungus
• Endemic area - Northern Thailand, Indochina Southern China • Prior to AIDS, systemic human infection extremely rare • Now very common AIDS-related opportunistic infection in endemic area ~20% • Seen elsewhere in immigrants and travelers |
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Penicilliosis – Clinical
• Disease – Symptoms? (3); usu. for >__ weeks – Usually with 1 or more _____ lesions – May have (3) • Diagnosis – ? • Therapy – _________ followed by __________ |
• Disease
– Fever, malaise, weight loss; usu. for >4 weeks – Usually with 1 or more skin lesions – May have lymphadenopathy, hepatosplenomegaly, cough • Diagnosis – Pathology or culture (skin lesion, bone marrow or lymph node biopsy) • Therapy – Amphotericin B followed by itraconazole |
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Paracoccidioidomycosis
•Caused by? • aka? (looks like blasto) |
Caused by paracoccidioides brasiliensis
Aka “South American blastomycosis” |
