Term
| Factors predisposing to infection |
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Definition
- neutropenia and defects in phagocytic defenses
- defect in cellular immunity
- defects in humoral immunity
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Term
| neutropenia and phagocytic defense defects (epidemiology and infection severeity) |
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Definition
- pts post chemo or other myelosuppresive therapy, bone marrow transplat pts, acute leukemia
- incidence and severity of infection inversely proportional to absolute neutrophli count
- risk of infection significant at ANC less than 500
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Term
| neutropenia and defects in phagocytic defenses (location of infection) |
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Definition
- offending organism usually colonizes area that becomes infected
- location
- skin- catheter related with staph, gram neg. fungi
- oropharynx- oral candidiasis, HSV
- lungs- bacterial, fungal pneumonia
- colon/perianal area- abscess
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Term
| neutropenia/phagocyte defect (causative agents |
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Definition
- gram negatives: E coli, P. aeruginosa, K. pneumoniae
- gram positives: S aureus and epidermidis
- fungi: Candida, Aspergillus, Mucor
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Term
| defect in cellular immunity (epidemiology) |
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Definition
- commonly in pts with AIDS, Hodgkin's lymphoma, monoclonal Ab therapy, long term corticosteroid use
- infection usually due to opportunistic infection
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Term
| cell immunity defects: opportunistic pathogens |
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Definition
- bactera: L. monocytogenes, Mycobact, Nocardia, Legionella, Salmonella
- Fungi- Cryptococcus, Histoplasma, Coccidioides, Pneumocytis
- Virus: VZV, HSV, CMV
- helminths: strongyloides, stercoralis
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Term
| defect in humoral immunity: epidemiology |
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Definition
- commonly in pts with agammaglobinemia, MM, CLL w/hypogammaglobinemia, splenectomized pts, sickle cell disease
- offending organisms are encapsulated, pyogenic bacteria (ex: S. pneumonia, H. influenza)
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Term
| pt with fever and neutropenia: clinical approach |
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Definition
- rapid initiation of empiric antimicrobial therapy manditory
- fever may be the only symptom
- predict ID of causitive agent is difficult
- perform thorough physical exam
- baseline studies
- labs: CBC
- live, renal function tests
- urinalysis
- blood and urine culture
- CXR
- direct specific dx test at most likely sites of infection
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Term
| common infections of neutropenic hosts |
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Definition
- septicemia/bacteremia
- oropharyngeal infection
- pulmonary
- skin/ST
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Term
| infections of neutropenic hosts: septicemia/bacteremia clinical approach |
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Definition
- high mortality
- outcome correlate to neutrophil count and control of underlying disease
- fever may be only symptom
- consider fungemia in pts already on antibacterials
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Term
| infections of neutropenic hosts: oropharyngeal infections (cauitive agents, symptoms) |
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Definition
- signs/symptoms
- mucositis
- mucosal ulcerations
- gingivostomatitis
- peridontal infections
- causative agents
- HSV
- Candida
- bacterial infections
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Term
| neutropenic host infections: pulmonary infections (cause, dx, causative agents) |
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Definition
- either primary infection or secondary to bacteremia
- spectrum of infection includes bacterial, fungal, and viral (CMV in setting of BMT)
- dx
- bronchoscopy
- transbronchial biopsy
- open lung biopsy
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Term
| neutropenic host infections: skin and ST infections (epidemiology, causative agents) |
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Definition
- epidemiology- pts usually with long term intravascular devices
- causative agents
- offending organisms usually skin flora
- hospitalized pts- gram negatives and fungi
- cutaneous punctures from any procedure lead to sever infections
- perianal cellulitis may result in gram negative sepsis or anaerobic infections
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Term
| principles of therapy in neutropenic hosts |
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Definition
- initial antimicrobial therapy is empiric
- gram negative coverage is mandatory
- pathogen IDed, change antibiotic regimen according to susceptibility pattern of organism
- recovery of neutrophil count is a major prognostic factor
- control of underlying illness important prognostic factor
- pts remaining febrile despite antibacterial coverage- begin antifungal therapy
- modify therapy according to clinical event
- ex: anti Staph coverage if catheter site appears erythematous
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Term
| preventative measures for neutropenic hosts |
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Definition
- isolation
- consider px antimicrobials
- G-CSF
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Term
| HIV related opportunistic infection: risk based on what? |
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Definition
- risk of acquiring infection based on degree of immunosuppression
- CD4 less than 200: PCP
- CD4 less than 100: Crytpococcal infections, MAI, CMV, toxo, cryptosporidium
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Term
| HIV related opportunistic infections: the oropharyngeal infections |
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Definition
- oral candidiasis
- oral hairy leukoplakia
- oral ulcers
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Term
| HIV opportunisitic infections: oral candidiasis (causative agents, clinical features, dx) |
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Definition
- causative agent: Candida albicans
- clinical features
- appear as white plaques
- involve soft/hard palate, tonsils, esophagus
- can occur in pts with high CD4 counts
- dx- exam, KOH smear
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Term
| HIV opportunistic infections: oral hair leukoplakia (clinical features, causative agent, dx) |
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Definition
- clinical features
- appear as raised, white lesions on lateral aspect of tongue
- causative agent- EBV replication in epithelium of mucosa
- dx- exam, biopsy
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Term
| HIV related infections: oral ulcers (causative agent, clinical feature, dx) |
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Definition
- causative agent and clinical feature
- HSV 1 and 2: small painful ulcers on erythematous base
- CMV- large, shallow ulcers
- aphthous stomatitis- ulcerations with exudate at base
- dx- culture, biopsy, EM for CMV
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Term
| HIV related infections: name the cutaneous infections |
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Definition
- HSV
- VZV
- bacilliary angiomatosis
- molluscum contagiosum
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Term
| HIV related infections: HSV (clinical features, dx) |
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Definition
- dx- Tzanck smear, culture
- clinical features
- genital lesions may coalesce, form large ulcers
- ulcers may be secondarily infected by bacteria
- infection can be complicated by radiculomyelitis and proctitis
- frequent recurrences can occur irrespective of high CD4 count
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Term
| HIV related infections: VZV (dx, clinical features) |
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Definition
- recurrent dermatomal outbreaks and disseminated disease can occur
- reactivation can occur at high CD4 counts
- dx by smear and culture
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Term
| HIV related infections: baciliary angiomatosis (causative agent, clinical disease) |
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Definition
- causes both cutaneous and visceral disease
- causative agent: Bartonella henselae
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Term
| HIV related infection: molluscum contagosum (causative agent, appearance) |
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Definition
- appearance- small flesh colored umbilicated lesions
- causative agents- poxvirus
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Term
| HIV related infections: CMV retinitis (clinical features, prognosis w/o tx, dx) |
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Definition
- clinical symptoms
- progressive visual loss
- blurring
- "floaters"
- dx- fundascope exam reveal coalescing white exudates with surrounding hemorrhage and edema
- prognosis- w/o tx, will progress to retinal detachment and visual loss
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Term
| HIV related infections: name pulmonary infection |
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Definition
- recurrent bacerial pneumonias (S pneumonia, H flu, S aureus, gram negative)
- PCP
- other fungal pneumonias
- Aspergillis
- Histoplasma
- Cryptococcus
- mycobacterial infections
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Term
| HIV related infections: PCP clinical manifestations |
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Definition
- insidious onset of fever, sweats, fatigue, non productive cough
- dyspnea is initially exertional, but progesses with impairment of gas exchange
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Term
| HIV related infections: PCP dx |
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Definition
- blood gases reveal reduced oxygen levels and commonly low PCO2 levels
- CXR most commonly reveal interstitial infiltrates, but lobar, nodular, cavitary, asymmetric patterns can also occur
- sputum, bronchoalveolar lavage or biopsy specimens are sent for staining (ex: silver, Diff Quik)
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Term
| HIV related infections: mycobacterial infections (prognosis, causative agents, dx) |
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Definition
- increased risk of primary and reactivation TB
- pts with more advanced HIV infection are more likely to have disseminated disease
- MAI associated pulmonary disease is rare
- M kansaii is most common non-TB pulmonary mycobacterial infection
- dx- sputum analysis and bronchoscopy
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Term
| HIV related infections: name the GI infections |
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Definition
- CMV
- cryptosporidium
- other interstitial parastic infections
- Microsporidium
- Isospora
- Giardia lambila
- Entamoeba histolytica
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Term
| HIV related infections: CMV GI infection (clinical features, dx) |
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Definition
- clinical features
- can effect entir GI system: esophagitis, gastritis, colitis
- present with odynophagia, diarrhea, proctitis, fever, abdominal pain
- can cause acalculous cholecystitis
- dx- endoscopy/colonoscopy with biopsy and EM
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Term
| HIV related infection: cryptosporidum |
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Definition
- clinical features
- usually causes persistant diarrheal disease
- can also cause acalculous cholecystitis
- dx- examine stool for ova, parasites
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Term
| HIV related infections: name CNS infections |
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Definition
- Cryptococcus
- Toxo
- CMV
- progessive multifocal leukoencephalopaty (PML)
- JC virus
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Term
| HIV related infections: CMV CNS infection (clinical features, dx) |
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Definition
- clinical features
- polyradiculopathy- ascending weakness and loss of relfexes as well as meningoencephalitis
- can progress to flaccin paralysis
- dx- CSF analysis, CSF CMV PCR, CT scan
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Term
| HIV related infections: PML (clinical features, dx, causative agent) |
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Definition
- clinical features
- rapidly progressive focal neurological deficits, most commonly hemiparesis, visual field defects, cognitive impairments
- causative agent- polyomavirus (JC virus)
- dx- CSF JC virus PCR, MRI
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Term
| HIV related infections: MAC disseminated infections (clinical features, dx) |
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Definition
- clinical features
- fever, sweats, wt loss, hepatosplenomegaly, adenopathy, anemia
- focal disease with isolated adenitis can also occur
- dx- blood culture, bone marrow biopsy, LN biopsy
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Term
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Definition
- px at CD4 less than 200
- SUF-TRI prefered
- other options: pentamidine, dapson, atovaquone
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Term
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Definition
- begin px at CD4 count less than 100
- px with Clarithromycin/Azithromycin
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Term
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Definition
| px with INH for all pts with positive PPD or close contacts of pt with TB |
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Term
| prevention of recurrent pneumococcal infections |
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Definition
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