Systemic Fungal Diseases Flashcards
Systemic candidiasis dx?
- may be difficult to isolate
- blood cultures are positive about 50% of the time
- May isolate organisms from urine or sputum (tx individualized (infection vs. colonization)
- isolated candida from blood cultures is considered a sign of serious disease until proven otherwise
- Fundoscopic exam to exclude endophthalmitis
Hepatosplenic candidiasis?
- secondary to aggressive chemotherapy and prolonged neutropenia
- fever and variable abdominal pain may be present
Invasive disease of systemic candidiasis?
- skin, brain, meninges, myocardium, eyes, muscles
- mortality is around 30%
- tx: IV antifungal tx such as fluconazole
What can be seen in disseminated candidiasis?
- tiny pustular lesions due to hematogenous dissemination of Candida albicans can be seen in pt also will see fever -> sepsis
- Can see large erythematous, nodular lesions with central necrosis in a pt with acute leukemia and disseminated candidiasis.
- Muscle abscess containing yeast
- go to the kidney: see abscesses in the kidney
Where is histoplasmosis found in the United states?
- Major river valleys: In Ohio and Mississippi river valleys
What is the source of histoplasmosis?
- How are humans infected?
- found in the soil: from bird or bat droppings
- inhalation of spores
- infection occurs 7-21 days post exposure
- lymphatogenous spread to other organs
What is the fungus that causes histoplasmosis?
- Histoplasma capsulatum
How are many cases of histoplasmosis detected?
- incidentally on X-ray because most cases are asymptomatic
- past infection may be noted by calcifications on routine X-rays: lungs and spleen
- This can’t reactivate but a lot of people from this regions will have nodules in lungs
What is acute pulmonary histoplasmosis?
- infection of the lungs
- can be relatively severe: severe fatigue and fever
- duration is 1 week - 6 months
- rarely fatal
Who does chronic pulmonary histoplasmosis effect? what will you see on a CXR?
- older pts and pts with underlying chronic lung disease
- CXR: apical cavities, infiltrates, nodules
What os progressive disseminated histoplasmosis and what can it be associated with?
- can be assoc. with underlying HIV (CD4 count hx is key)
Presentation of progressive disseminated histoplasmosis?
- may be similar to septic shock
- will have a fever, dyspnea, cough, and wt loss
- can be fatal within 6 weeks or less
What organs are involved in progressive disseminated histoplasmosis?
- ulcers in oropharynx
- hepatosplenomegaly
- GI involvement mimics inflammatory bowel disease
- CXR shows a miliary pattern (small lesions everywhere)
Dx studies for Histoplasmosis?
- CXR
- CBC, CMP
- alkaline phosphate, lactate dehydrogenase, and ferritin will all be elevated
- Sputum culture most likely to be negative in acute disease and positive in chronic disease.
- Bronchoalveolar lavage Ag testing
- **urine Ag test (>90% sensitivity)
- blood cultures: may takes weeks
What is the most helpful test in dx histoplasmosis?
- urine ag test (>90% sensitivity)
Tx of histoplasmosis
- refer to ID specialist
- Itraconazole 200-400 mg/d
- duration: weeks to months
- severe illness: IV amphoteracin B
- AIDS related histoplasmosis: lifelong suppressive therapy with itraconazole
Where is coccidioidomycosis endemic?
- Southwestern US, Mexico, Central America, South America
How does coccidioidomycosis occur?
Also called?
- infection occurs secondary to inhalation of molds from endemic areas
- Valley fever, San Joaquin valley fever
- more severe cases in immunocompromised pt
pt with coccidioidomycosis presents with what sxs?
- variety: can be asymptomatic pedal edema chest pain cough with blood tinged sputum fever, night sweats HA joint stiffness muscle pain anorexia erythema nodosum ****(hallmark)
When does erythema nudism occur with coccidioidomycosis?
- may occur 2-20 days after onset of respiratory symptoms
these are swollen red nodules
disseminated coccidiodomycosis can affect what?
- skin (erythema nudosum, verrucous skin lesions)
- lungs (cavities, infiltrates, empyema, pleural effusion)
- Bones (lytic lesions)
- soft tissues (abscesses)
- lymph nodes (hilar and/or mediastinal lymphadenopathy, lymphadenitis and abscess formation)
- meningitis
Most common presentation of coccidioidomycosis?
acute pneumonia
What will labs look like in coccidioidomycosis?
- leukocytosis
- eosinophilia
- ELISA fro IgM and IgG abs
- Tissue or bone bx may reveal spores (pleural lesion: empyema, or lymph node)
- blood cultures rarely positive
- spinal fluid: complement fixing abs (dx in 90%), increased cell count, lymphocytosis, reduced glucose, culture positive in only 30%
If you see multiple thin walled cavities, and patchy areas with ill defined borders on CXR what would be your differential?
- Coccidioidomycosis, lung abscesses, chronic pulmonary tb, chronic pulmonary histoplasmosis
Tx of coccidioidomycosis?
- Refer to ID specialist
- Fluconazole or itraconazole daily for months
- Amphotericin B IV for severe disseminated cases
- may required prolonged therapy
- surgical incision and drainage of abscess formation
What causes Cryptococcosis?
- caused by Cryptococcus neoformans
yeast that is found in the soil and on dried pigeon poop
What is cryptococcus neoformans the most common cause of?
- most common cause of fungal meningitis
RFs of cryptococcosis?
- chemo for hematologic cancer, Hodgkin lymphoma, corticosteroid therapy, transplant recipients, TNF inhibitor therapy, HIV (immunocompromised pts)
- rare in immunocompetent persons
3 forms of cryptococcosis infection?
- cutaneous
- respiratory
- meningeal
Signs and sxs of cryptococcosis?
- pulmonary: can lead to respiratory failure
- any organ can be infected
- CNS predominates: (meningitis)
HA usually first sx
confusion
mental status changes
cranial nerve abnormalities
N/V, fever
Dx of cryptococcosis?
- cryptococcal antigen can be found in the infected organ and often in the serum of AIDS patients
- resp: sputum culture or pleural fluid
- lumbar puncture for meningeal involvement: increased opening pressure, increased protein, decreased glucose
- india ink prep shows budding, encapsulated fungal cells: meningitis
- *cryptococcal capsular antigen testing (dx)
Tx of cryptococcosis?
- referral to ID specialist
- Amphotericin B IV x 2 weeks
- followed by fluconazole x 8 weeks
Sxs of cryptococcosis?
HA, abnormal mental status, meningismus, respiratory sxs
Dx test for cryptococcosis?
- capsular polysaccharide Ag in CSF, sputum or urine is diagnostic
where is Aspergillosis found?
- in dead leaves (or other decaying vegetation), compost piles, stored grain, and on marijuana leaves
What is usually the cause of Aspergillosis?
- Aspergillus fumigatus
- ubiquitous in nature
When would tissue invasion of Aspergillus fumigatus occur?
- with immunosuppression: tx for autoimmune disease cancer bone marrow transplant solid organ transplant HIV - severe and prolonged neutropenia - high dose glucocorticoids
What is the most common cause of non-candidal invasive fungal infection in bone marrow and solid organ transplant pts?
- Aspergillus fumigatus
Manifestations of Aspergillosis?
- allergy (chronic allergic response)
- airway or lung invasion (most common): tracheobronchitis, rhinosinusitis
- cutaneous
- extrapulmonary dissemination: brain, eyes, kidney, liver, heart, GI
What does aspergillosis most commonly affect and what are the sxs assoc’d with this?
- most commonly affects the lungs
- sxs: fever, chest pain, SOB, cough, hemoptysis
What will you see on a CXR of aspergillosis?
- single or multiple nodules with or w/o cavitation, patchy or segmental consolidation, peribronchial infiltrates
Dx of aspergillosis?
- allergic disease: high levels of IgE and IgG Aspergillus precipitins in the blood
- Galactomannan Ag from serum or bronchioalveolar lavage fluid (parts of cell wall of Aspergillus sp)
- beta-d-glucan assay (new): part of cell wall of mult types of fungus, use for invasive candidial infections and Aspergillus
- ***PCR for aspergillus
- culture
- Bx
- CT scan of lungs: ground glass infiltrates with “halo sign” then development of a cavitary lesion, converts to air-crescent sign after neutrophil recovery
When does allergic bronchopulmonary aspergillosis occur?
- with preexisting asthma and worsening bronchospasm and pulmonary infiltrates
- waxing and waning course
- may result in bronchiectasis and fibrotic lung disease
- will see high levels of IgE and IgG Aspergillus
Tx of Allergic bronchopulmonary aspergillosis?
- antifungals and steroids (would generally want to stay away from steroids but since it involves airway we want to decrease inflammation and ease breathing)
What are some features of invasive life-threatening aspergillosis?
- seen in profound immunodeficiency
- pulmonary manifestations: patchy infiltrates, necrotizing pneumonia
- sinus invasion
- multi-organ involvement: tissues infarct as organism grows into blood vessels
- ## Hematogenous spread is possible
Tx of invasive life-threatening aspergillosis?
- high dose multiple agent anti fungal therapy
- systemic azole, amphotericin B
