Systemic Fungal infections Flashcards
1
Q
Systemic Candidiasis
- how do you isolate the organisms?
- signs/sx
- Tx
A
isolate organisms from urine or sputum or blood.
- if candida can be isolated from blood cultures this is a serious disease until proven otherwise.
- blood cultures are only positive 50% of the time
- Signs/sx:
- -hepatosplenic candidiasis may be secondary to aggressive chemotherapy and prolonged neutropenia, fever and variable abd pain may be present.
- -may infect skin, brain, meninges, myocardium, eyes, muscles
- -tiny pustular lesions d/t hematogenous dissemination or large erythematous nodular lesions with central necrosis
- -abscess in leg/kidney
-Tx: IV antifungal tx such as fluconazole
2
Q
Histoplasmosis -what region is most likely to contract? -where is this fungus found? -transmission? -fungal infection site in the body? -what are the three types of histoplasmosis and their sx/findings?
A
- ohio mississippi river valley
- bird and bat droppings in the soil
- inhalation of the spores
- fungal infection has lymphatogenous spread to other organs.
- 3types
- Acute pulmonary
- -sever fatigue & fever (1wk to 6mo)
- Chronic Pulmonary
- -older pt
- -underlying chronic lung disease
- -CXR shows apical cavities, infiltrates, and nodules
- Progressive Disseminated:
- -fever, multiorgan system involvement
- -presentation similar to septic shock
- -fever, dyspnea, cough, weight loss
- -may be fatal within 6 weeks
- may be associated with underlying HIV or other states of immunosuppression
- -ulcer in oropharynx, hepatosplenomegaly, GI involvement, CXR show miliary patter.
Sx:
- infection occurs 7-21 days post exposure
- most cases are asymptomatic and detected incidentally on xray
- past infection may be noted by calcification on lung/spleen on xray
3
Q
Diagnostic Studies: Histoplasmosis
A
- CXR, CBC, CMP, alkaline phosphatase, LDH, and ferritin are all elevated.
- sputum culture most likely to be negative in acute disease and positive in chronic disease
- bronchoalveloar lavage ag testing
- URINE AG TEST*** (90% sensitivity)
- Blood cultures (may take weeks for results)
4
Q
Tx Histoplasmosis
A
- refer to ID specialist
- Itraconazole 200-400mg/d (systemic)
- duration: weeks to months
- severe illness IV amphoteracin B
- AIDS related histoplasmosis: lifelong suppressive therapy w/ itraconazole
5
Q
Coccidiodomycosis
- what region most likely to contract this?
- what causes infection?
- sx
A
- endemic in southwest US, parts of mexico
- inhalation of molds
Sx:
- asymptomatic
- pedal edema
- chest pain
- cough w/ blood tinged sputum
- fever, night sweats
- HA
- Joint stiffness
- muscle pain
- anorexia
- erythema nodosum
- disseminated sx:
- -skin (erythema nodosum, verrucous skin lesion)
- -lungs (cavities, infiltrates, empyema, plueral effusion)
- -bones (lytic lesion)
- -Soft tissues (abscesses)
- -Lymph nodes (hilar and or mediastinal lymphadenopathy
- -meningitis
6
Q
what is erythema nodosum? WHen does this occur?
A
- swollen painful red nodules typically on the legs or arms in pts infected with coccidiodomycosis
- may occur 2-20 days after onset of respiratory sx
7
Q
what is the most common presentation of coccidiodomycosis?
A
acute pneumonia
8
Q
Lab findings in coccidiodomycosis
A
- leukocytosis
- eosinophilia
- ELISA for IgM or IgG aby to coccidoidmycosis
- Tissue or bone biopsy may reveal spores
- blood cultures rarely positive
- Spinal fluid* (diagnostic in 90%), increased cell count, lymphocytosis, reduced glucose
9
Q
CXR findings in Coccidiodomycosis
A
multiple thin walled cavities 2-4cm diameter. , have poorly defined borders.
10
Q
Tx Coccidiodiomycosis
A
- Refer to ID
- fluconazole or itraconazole daily for months
- amphoteracin B IV for severe disseminated
- surgical incision and drainage of abscess formation
11
Q
Cryptococcus
- what causes infection?
- risk factors
- what are the 3 forms of infection?
A
-cryptococcus neoformans yeast that is found in soil and on dried pigeon poop
- Risk:
- chemo for hematologic cancer, hodgkin lymphoma, corticosteroid therapy, transplant pt, TNF inhibitor therapy, HIV
- 3 forms infection:
1. ) cutaneous
2. ) respiratory
3. ) meningeal
12
Q
What is the most common cause of fungal meningitis?
A
-Cryptococcosis
13
Q
Sings and Sx of Cryptococcus
A
- pulmonary*: may lead to respiratory failure
- any organ can be affected
- CNS predominates***:
- HA (usualy 1st sx)**
- Confusion
- Mental status change*
- cranial nerve abnormalities
- n/v
14
Q
Dx Cryptococcus
A
- cryptococcal ag can be found in the infected organ and often in the serum of AIDS patients
- Respiratory: sputum culture or pleural
- LP for meningeal involvement: increased opening pressure, increased protein, decreased glucose, cryptococcal capsular ag*****
- india ink prep; shows budding, encapsulated fungal cells
15
Q
Tx Cryptococcus
A
- Refer to ID
- Amphoteracin B IV x2wk
- followed by fluconazole x 8wks
