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163 Cards in this Set
- Front
- Back
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Viral capsid and envelope are sensitive to . . .?
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Capsid: bleach
Envelope: detergents and bleach |
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Measles (Rubeola) (type of virus, main symptom)
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Paramyxovirus
-ssRNA enveloped Fever then rash w/ head first, Koplik's spots |
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Measles (transmission, prevention, complications)
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Respiratory transmission very infectious
Live attenuated vaccine Complications in < 5yo: otitis media, pneumonia |
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DNA viruses
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HHAPPPPY
Hepadna Herpes Adeno Pox Parvo Papilloma Polyoma |
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German measles (Rubella) (type, transmission, symptoms, prevention)
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Togavirus, +RNA, enveloped
Respiratory Mild URI, variable rash Congenital rubella syndrome Live attenuated vaccine |
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Congenital rubella syndrome
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Intrauterine 1st trimester infection
Deafness, growth retardation, 20% mortality |
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Mumps (type, transmission, symptom, prevention)
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Paramyxovirus, -RNA, enveloped
Salivary gland swelling Respiratory transmission Live attenuated vaccine |
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Smallpox (type, transmission, symptom)
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Poxvirus, dsDNA, enveloped
High mortality Respiratory transmission Cutaneous pustules w/ central depression |
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Erythema infectuosum, Fifth disease (type, symptoms, who does it effect?)
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Parvovirus B19, ssDNA, enveloped
"Slapped cheeks" -> red/lacy trunk rash effecting children |
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Roseola infantum, 6th disease (HSV-6) (Type, who it infects, 3 symptoms)
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Herpesvirus, dsDNA, enveloped
Children < 2yo Minor respiratory symptoms and fever w/ postfebrile rash |
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Viruses a/w respiratory infections (6)
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Influenza
Respiratory syncytial virus (RSV) Paramyxovirus Adenovirus Rhinovirus Coronavirus |
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Influenza (type, transmission, sx, complications)
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Orthomyxovirus, -RNA, envelope
Respiratory transmission Fever, chills, headache Cx - secondary bacterial infections can be fatal |
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Antigenic drift vs antigenic shift
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Drift - point mutation in HA or NA causing lack of Ab recognition -> different strains -> epidemics and changing flu vaccines
Shift - reassortment of HA and NA segments b/w different species strains -> pandemics |
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Influenza genomes and key proteins
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Segmented RNA
Hemagglutinin - binds cell receptor (sialic acid) for fusion Neuraminidase - cleaves sialic acid for virion release M2 - ion channel necessary for uncoating |
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Influenza types (severity, what animals are infected, shift or drift?)
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A - severe; birds, mammals, humans; shift and drift
B - moderate; humans; drift C - mild; humans; drift |
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Influenza Dx and Rx (4)
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Dx - Rapid antigen testing, viral culture+isolation, RT-PCR
Rx - symptoms: hydration, rest, antipyretics antivirals w/in 2 days: amantadine, rimantadine (for type A), tamiflue, relenza |
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Respiratory syncytial virus (who is infected, transmission)
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By 2yo everyone infected
Transmission by direct contact Severe in infants |
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Parainfluenza virus causes:
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Croup
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Adenovirus
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Common cold
Pharyngitis |
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Which viruses cause common cold?
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40-50% rhinoviruses
10-30% coronaviruses rest adenoviruses |
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Dengue (type, serotypes, where?)
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Flavivirus, +RNA, enveloped, mosquito borne
4 serotypes which don't offer cross resistance Tropics |
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Dengue (clinical, labs, rx, prevention)
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Clinical: sudden fever, malaise, Break-bone fever, 1% progress to dengue hemorrhagic fever
Labs: leukopenia, thrombocytopenia Rx: supportive Prevention: none |
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Dengue hemorrhagic fever (what happens, 1 positive test)
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More common w/ 2nd infection
Plasma leakage Positive tourniquet test |
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Chikungunya (type, where, how, common symptom, rx, prevention)
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RNA
Tropical africa, asia mosquito borne Joint pain lasting months Rx - supportive Prevention - none |
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Yellow fever (type, how, where)
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Flavivirus, +RNA, enveloped
Mosquito borne Tropics |
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Yellow fever (symptoms, rx, prevention
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Fever, flu, some progress to hemorrhagic fever, jaundice, shock
Rx - supportive Prevention - live attenuated vaccine |
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Fecal-oral viruses (3, what family?, type)
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Picornaviruses -> enteroviruses
Poliovirus Coxsackie Echovirus +RNA, non enveloped |
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Polio (type, symptoms, prevention)
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Picornavirus, +RNA, non-env
Anterior horn motor and autonomic nerves affected Spinal most common Prevention - inactivated injection vs oral live attenuated |
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Coxsackie (type, symptoms, 3 diseases)
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Picornavirus, +RNA, non-env
90% asymptomatic w/ undiff fever Hand-Foot-Mouth syndrome Herpangina - febrile pharyngitis Myocarditis |
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Rotavirus (type, main clinical and path, prevention)
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Reovirus, dsRNA, non-env
Main cause of gastroenteritis in infants/children via loss of brush border enzyme by viral toxin Prevention - rotateq live oral rotarix live attenuated |
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Norovirus (type, main system, and where?)
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Calcivirus, RNA
Gastroenteritis outbreaks a/w nursing homes, cruise ships, traveler's diarrhea |
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5 major causes of encephalitis
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VIRUSES
Tumors Drugs Vasculitis (lupus) Acute demyelinating encephalomyelitis |
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Viral causes of encephalitis (4 main classes)
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Arboviruses (WEE, SEE, WNV)
Picornaviruses (Coxsacki, polio, echo) Herpes Adeno |
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Most treatable cause of sporadic fatal encephalitis
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Herpes simplex
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Herpes simplex encephalitis (entry, main finding, dx, rx)
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Entry: peripheral nerves to CNS
Temporal lobe necrosis Dx - PCR for HSV BUT TREAT FIRST Rx - acyclovir |
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Eastern equine encephalitis (hosts, entry, 2 clinical)
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Birds -> mosquitos -> humans and horses
Hematogenous entry Abrupt onset fever and pleocytosis |
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West Nile Virus (type, clinical, who is at highest risk, 3 clinical)
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Flavivirus, +RNA
Most common encephalitis in USA Fever, elderly at highest risk Encephalitis, meningitis, polio-like flaccid paralysis |
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Negri bodies
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Rabies
Eosinophilic cytoplasmic inclusions - viral particles |
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Acute hepatitis (incubation, clinical 4)
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Months incubation
Prodrome - flu-like, highly infectious Dark urine, jaundice, hepatomegaly |
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Hepatitis A (type, transmission, epi, outcome, prevention)
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Picornavirus, +RNA
Fecal-oral transmission Endemic in developing countries Self-limited - no chronic infectin Prevention - inactivated vaccine |
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Hepatitis E (type, incubation, outcomes)
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Enteric, expectant mothers, epidemic
RNA hepesvirus Short incubation w/ no chronic disease Pregnant women are 20% of fulminant -> death |
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Hepatitis B (type, transmission, incubation, outcome, prevention)
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Hepadnavirus, dsDNA
Blood-borne Long incubation 10% chronic (HBsAg +) Prevention - vaccine of recombinant HBsAG |
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Outcomes of chronic viral hepatitis (3 endpoints)
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After 20 yrs of fibrosis -> cirrhosis ->
Stable or Liver failure or Hepatocellular carcinoma |
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Hepatitis D (type, transmission, outcomes 2)
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Defective RNA virus that requires HBsAG from HBV
Blood-borne Superinfection much more likely to be chronic compared to coinfection w/ HBV |
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Hepatitis C (type, transmission (1 big one), incubation, outcomes, serology)
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RNA flavivirus
Blood-borne (IVDU) Long incubation 70% chronic (worse w/ HIV) and HCV-RNA+ Anti-HCV + NO VACCINE |
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Hepatitis transmission
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HAV and HEV - fecal-oral
HBV, HCV, HDV - blood-borne |
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Viral hepatitis genomes and incubations
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All are RNA except HBV
Enteric viruses have short incubations at 1 month (HAV, HEV) and do not cause chronic infection |
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HIV (genome and 3 major proteins)
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Enveloped lentivirus, retrovirus
Gag: core proteins Pol: RT polymerase Env: envelope proteins |
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HIV p24
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Capsid protein
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HIV gp41 and gp120
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Envelope proteins
gp41 - fusion and entry gp120 - attachment to host T cell |
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4 stages of HIV infection
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1. Flu-like, rash (acute)
2. Feeling fine (latent) - virus replicates in lymph nodes 3. Falling CD4 count 4. Final crisis |
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B-cell activation in late stage HIV (3)
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Hypergammaglobulinemia
Non-specific production of Ab Risk for encapsulated organism infection |
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HIV serology
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Antibodies to HIV don't occur til 2-6 wks after infection, so serology is not useful in early diagnosis
Order HIV RNA levels |
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2 HIV phenotypes
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Non-syncytium (CCR5) - normal virus that is transmitted
Syncytium (CXCR4) - fusion of infected and uninfected CD4 cells -> higher virulence HIV can progress from NSI to SI |
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HIV chemokine co-receptors
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Necessary for HIV entry
M-tropic virus uses CCR5 on mac, monos, and T cells T-tropic virus uses CXCR4 on T cells Homozygous CCR5 mutation = immunity |
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AIDS OIs (8)
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PCP
Cryptococcal meningitis Recurrent bacterial pneumonia Candidal esophagitis CNS toxoplasmosis TB Disseminated MAC CMV |
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AIDS OI Prophylaxis (3 w/ rx)
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PCP (CD4 < 200, thrush) - Bactrim
Toxoplasma (CD4 < 100, positive toxo Ab) - Bactrim MAC (CD4 < 50) - Azithromycin |
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Immune reconstitution inflammatory syndrome (IRIS) (what happens, clinical)
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AIDS pt has low CD4, started on ART ->
Immune system recovers a little -> Now is strong enough to mount response to previously acquired OI Fever |
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IRIS associated infections (7)
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TB, MAC
PCP Toxo HBC/HCV CMV VZV |
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Mucocutaneous candidiasis (CD4, 2 types, Rx)
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CD4 < 200
Oropharyngeal or esophageal (painful) Rx: thrush - nystatin swallow, fluconazole; candidal esophagitis - fluconazole |
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Pneumocystis Pneumonia (PCP) (CD4, 2 clinical, rx, prophlyaxis)
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CD4 100-200
Progressive dyspnea on exertion Butterfly pattern on CXR Rx - bactrim, prednisone + TMP-SMX Prophylaxis when CD4 < 200 w/ TMP-SMX |
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Cryptococcal neoformans (CD4, 3 cardinal clinical, rx, prophylaxis)
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CD4 100-200
Meningitis Opening pressure > 200 India ink stain -> budding yeast Rx - amphotericin -> fluconazole Prophylaxis - no primary, but secondary until cd4 > 200 for 6 mo |
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Mycobacterium avium intracellulare complex (CD4, 4 clinical, rx, prophylaxis)
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CD4 < 50
Anemia, incr Alk Phos+LDH Lymphadenitis, granulomas Rx - COMBO clarithromycin+ethambutal Prophylaxis - CD4<50 -> azithromycin |
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Toxoplasmosis (CD4, 2 main clinical, rx, prophylaxis)
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CD4 < 100
Cerebral abscesses: ring-enhancing lesions in basal ganglia Eye pain/problems (chorioretinitis) Rx - pyrimethamine + leucovorin + antibiotic Prophylaxis - CD4 < 100 and toxo+ -> TMP-SMX |
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Cytomegalovirus (Cd4, 2 clinical, rx, prophylaxis)
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CD4 < 50
Any organ, but mostly retinitis Scrambled-eggs and ketchup Rx - intraocular gancilovir Prophylaxis - none of note |
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Cryptosporidia (CD4, 2 clinical, rx, prophylaxis)
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CD4 < 100
Enteritis, diarrhea Rx - HAART Prophylaxis - none |
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Scrambled-eggs and ketchup
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CMV
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Butterfly CXR
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PCP
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Opening pressure > 200
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Cryptococcal meningitis
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Lymphadenopathy, elevated alk phosph and ldh
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MAC
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Ring-enhancing brain lesions (basal ganglia predilection)
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Toxoplasmosis
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When to start ART in HIV
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History of AIDS-defining illness
Asymptomatic CD4 < 500 Pregnant |
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First line HAART
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2 NRTIs w/ one of either
NNRTI, protease inhibitor, or ritonavir |
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HAART classes (5)
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NRTIs
NNRTIs Protease inhibitors Integrase inhibitors Ritonavir |
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Nucleoside reverse transcriptase inhibitors (MOA, 4 examples)
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MOA - after phosphorylation by thymidine kinase in infected cell -> chain terminates polymerase
Ziduvine, tenofovir, emcitrabine, abacavir |
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NRTIs toxicity (3)
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Old drugs:
lactic acidosis (due to mito-toxicity) peripheral lipoatrophy New drugs: no mito toxicity |
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Non-nucleotide reverse transcriptase inhibitors (MOA, 3 examples)
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MOA - bind HIV-RT at different site than NRTIs, don't have to be phosphorylated
Nevirapine, efavirenz, declaviridine |
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Efavirenz (type, 2 SE)
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NNRTI
Teratogenic neural tube defects CNS effects |
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Nevirapine (type, SE)
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NNRTI
Serious hepatitis |
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HIV protease inhibitors (MOA, examples, SE (3))
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MOA - prevent viron assembly dependent protein cleavage
-navir: ritonavir, indinavir SE: lipohyperatrophy, hyperglycemia, GI intolerance |
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Ritonavir (use, SE)
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Protease inhibitor used to inhibit CYP3A4 metabolism of many other antiretrovirals
Drug interactions: lots of drugs |
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Raltegavir (MOA, SE)
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HIV integrase inhibitor
Few side effects but prone to resistance |
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Maraviroc (MOA, SE)
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CCR5 entry inhibitor by binding CCR5
Virus can shift preference for CXCR4 and evade drug SE: few |
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Enfuvirtide (MOA, use, SE)
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Entry inhibition by binding gp41 so virus can't fuse w/ CD4 cells
Used in advanced drug resistance SE: hypersensitivity reaction at injection site |
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HBV treatment indications and first line therapy (2 drugs)
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Active liver disease (chronic hepatitis or cirrhosis)
Nucleoside/tide analog (entecavir or tenofovir) |
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Lamivudine
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Cytosine nucleoside analog
Old drug for HBV |
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Entecavir
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Nucleoside/tide analog for HBV phosphorylated intracellularly
Avoid in HIV/HBV |
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Tenofovir and adefovir (MOA, use, SE)
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Adenosine nucleotide for HBV analog phosphorylated intracellularly
SE: renal tubular damage, tenofovir much safer |
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Pegylated interferon (MOA, use, SE (2))
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HBV/HCV
Enhances antiviral state by inducing immune response/blocking viral protein synthesis SE: common: flu-like, bone marrow suppression |
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HCV treatment indications and standard treatment
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Chronic hepatitis w/ significant fibrosis
Curable unlike HBV b/c RNA doesnt integrate PEG-IFN + oral ribavirin + PI |
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Ribavirin (use, MOA, 2 tox)
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HCV
Inhibits viral dependent RNA polymerases SE: severe hemolytic anemia, teratogenic |
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HCV protease inhibitors
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Telepravir, bocepravir
SE: anemia, drug interactions |
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8 human herpesviruses
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HSV-1 and 2
VZV EBV CMV KSHV HSV 6 and 7 (Roseala infantum) |
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HSV (transmisison, entry, spread, rx)
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HSV1 usually orally transmitted in childhood
HSV2 usually sexually transmitted in adults Mucosal entry, spreads to nerve -> ganglia (TNG or sacral) Rx - nothing for primary, only for reactivations |
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Recurrent oral herpes (path, symptom, rx)
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Reactivation of primary infection
Cold sores w/ prodrome of tingling/warmth Rx - acyclovir |
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Genital herpes
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>50% of reactivations can be asymptomatic but still shedding virus
Dx - clinical is insufficient, must do lab DFA or PCR Rx - acyclovir to shorten duration/severity of outbreaks |
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Severe HSV infections (3)
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Herpes encephalitis
Neonatal herpes Disseminated herpes in immunocompromised |
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Herpes simplex encephalitis (2 types, cardinal clinical finding, rx)
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Acute, necrotizing encephalitis
Neonatal - diffuse, mortality 100%, Children/adults - reactivation where virus travels to brain from TNG -> temporal lobe Rx - IV acyclovir |
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Neonatal herpes (transmission, 3 types, rx)
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Acquired at delivery
3 manifestations 1) mild disease - skin and mouth 2) severe encephalitis 3) disseminated Rx - acyclovir |
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VZV in children (transmission, entry, spread, 3 clinical, rx)
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Respiratory entry -> lymphoids -> other organs
Generalized vesicular rash, fever, lymphadenopathy Rx - self-limited |
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Congenital varicella
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Birth defects
Very rare |
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Varicella vaccine (2)
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Varivax live attenuated virus
Vaccinated pt still can get shingles! VariZIG - varicella Ig for urgent protection <96h from exposure |
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Smallpox vs chickenpox
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Chickenpox localized more to trunk
Smallpox everywhere evenly and lesions all at same stage |
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Shingles (clinical, whats unique about immunocompromised?, dx, rx (2), which ganglia?)
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Single (EXCEPT IMMUNOCOMPROMISED) recurrent infection decades after initial VZV infection
Unilateral painful vesicular eruptions in head or upper trunks Dx - clinical sufficient but can get labs for VZV DNA Rx - acyclovir and pain relievers for post herpetic neuralgia DORSAL ROOT GANGLIA, NOT TNG OR SACRAL |
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Zoster vaccine
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Zostavax for everyone >60 reduces occurrence and pain
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Epstein-Barr Virus (transmission, primary infections, entry and latency, rx)
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Transmission - saliva contact
Primary infection in children asymptomatic, in adolescents 50% get mono Enters epithelial cells in pharynx -> B lymphocytes latency Rx - supportive (no antivirals) |
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Infectious mononucleosis symptoms (4) and differential (3)
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White exudate on tonsils
Lymphadenopathy Pharyngitis Splenomegaly DDx- EBV > CMV (monospot neg, older patients) > adenovirus (no fatigue) |
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EBV diagnosis (2)
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> 10% atypical lymphocytes
+Monospot - transient appearance of EBV specific heterophile antibodies |
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Endemic EBV disease (2)
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Burkitt's lymphoma - NHL, affects jawbone, africa, children
Nasopharyngeal carcinoma - south china/taiwan, adults |
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Cytomegalovirus (transmission, latency, rx)
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Vertical and horizontal transmission thru saliva
Usually asymptomatic Latent in hematopoietic cells Rx - ganciclovir |
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CMV outcomes (4)
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Asymptomatic seroconversion
Congenital infection (10% microcephaly CMV mononucleosis (can occur more than once unlike EBV IM) Reactivations in immunocompromised |
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Influenza antivirals (4)
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Amantadine + rimantadine - M2 inhibitors (Influenza A)
Oseltamavir, zanamavir - NA inhibitors (A+B) |
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Amantadine (MOA, use, resistance?, tox (1))
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M2 inhibitor
Influenza A Resistance Tox: CNS |
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Rimantadine (MOA, use, resistance?, tox)
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M2 inhibitor
Influenza A Resistance Tox: fewer CNS |
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Zanamavir (MOA, use, resistance?, tox)
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NA inhibitor
Influenza A+B No resistance Tox: bronchospasm |
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Oseltamavir (MOA, use, resistance?, tox)
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NA inhibitor
Influenza A+B Low resistance Tox: GI |
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HSV antivirals (3, MOA)
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Acyclovir
Also valacyclovir and famciclovir Require phosphorylation to monophosphate by viral thymidine kinase -> triphophate inhibits viral DNA pol |
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Acyclovir (MOA, use, resistance?, tox
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Chain terminates viral DNA pol
HSV1,2, VZV Resistance via thymidine kinase independent mutants Tox: nephro, CNS |
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Famciclovir and valacyclovir
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Like acyclovir but don't have to dose as much
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Ganciclovir (MOA, use, resistance?, tox (2))
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Monophosphate formed by viral thymidine kinase -> inhibits viral pol
CMV (HSV1,2) (CMV lacks right thymidine kinase Resistance common if > 3 months rx Tox: nephro, bone marrow suppresion |
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Valganciclovir (what is it, 2 uses)
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Metabolized to ganciclovir
Prophylaxis in CMV or IV in severe CMV |
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Foscarnet (MOA, use, resistance?, tox (2))
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Inhibits viral DNA pol w/o having to be activated by a kinase
CMV, HSV No resistance Tox: considerable nephro, electrolytes |
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Cidofovir (MOA, use, resistance?, tox)
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Nucleotide analogue inhibits viral DNA pol
CMV, small pox No resistance Tox: nephro |
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Nematodes (transmission, 2)
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Roundworm
Fecal-oral Enterobius (pinworm) Strongyloides |
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Trematodes (1)
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Flatworm
Schistomiasis |
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Cestodes (3)
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Tapeworm
Echinococcus Taenia solium - teniasis, neurocysticercosis |
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Enterobius (type, clinical, dx, rx)
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Nematode
Pruritic anae Dx - scotch tape test Rx - whole family, pyrantel pamoate |
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Pyrantel pamoate (MOA, use, SE 2)
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Binds NMJ
Enterobius SE: GI, avoid in pregnancy |
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Strongyloides (type, entry+spread, clinical 1 KEY, dx, rx)
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Nematode
Penetrate skin -> blood vessels -> lungs -> cough up -> intestine -> hatch in bowel Subclinical for years w/ mild eosinophilia (HYPERINFECTION IN IMMUNOSUPPRESSED) Dx - larvae in stool Rx - Ivermectin |
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Ivermectin (MOA, use, SE)
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Blocks ion channels
Strongyloides SE: Pruritis |
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Teniasis (caused by, dx, rx)
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Taenia solium (cestodes-tapeworm)
Dx - eggs in stool Rx - praziquantel |
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Cysticercosis (type, 2 clinical, Dx, Rx
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Taenia solium (cestodes) -PIGS
Subq nodules in muscles, seizures due to host inflammation Dx - MRI Rx - steroids + anti epileptic + albendazole |
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Seizures, brain lesions, suq nodules, PIGS
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(neuro)cysticercosis (taenia solium)
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Sheeps, dogs, liver, abd pain
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( Cestodes)Echinococcus
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Praziquantel (MOA, 2 use, 3 SE)
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Damages integument of worm
Unmasking Ag Chlonorchiasis, schistomiasis SE: n/v, GI |
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Schistosomiasis (type, hosts, 4 clinical, rx, dx)
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Via snails
Liver fibrosis, cercarial dermatitis (hours), fever/chills/megaly (acute), liver (chronic) Rx - serology Dx - praziquantel |
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Malaria: falciparum vs vivax (where?)
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Falciparum - fever every 3nd day, global, knobs bind ICAM-1 and sequester in microvasculature
Vivax - every 3rd day, not in central or west africa, prefers reticulocytes |
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Malaria lifecycle (7)
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Mosquito injects sporozites ->
Infected hepatocytes make schizonts -> Ruptured schizonts into circulation -> [[Merozites infect RBC -> make trophozites (ring) -> schizont -> burst RBC -> merozites infect RBC]] -> Some trophozites make gametocytes taken up by next mosquito where sex happens [[erythrocyte cycle can persist indefinitely]] |
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Malara: sequestration
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Unique to falciparum
Infected RBC form knobs w/ PfEMP1 allowing iRBC to stick to endothelium -> accumulation of RBC in capillaries CEREBRAL and iRBC avoid splenic clearance |
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Malaria virulence factors (2)
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Duffy blood group Ag: P.vivax requires this Ag to enter into RBC (Africans lack it, so are immune)
PfEMP1 - protective immune responses are against it, but it's highly variant |
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Malaria mediators of host immunity (4)
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Sickle cell
GP6D deficiency B thal Ovalocytosis |
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Malaria clinical
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Fevers every 2nd day (3rd for P.malaria)
Anemia Splenomegaly |
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Malaria severe clinical (5)
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Cerebral malaria
Severe anemia Hemoglobinuria/renal failure Pulmonary edema/ARDS Hypoglycemia (utilization by parasites) |
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Malaria Dx (Falciparum vs vivax
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Presence of parasites in thick and think smears
Falciparum - normal sized RBC, stereo headphone ring forms Vivax - enlarged RBC, Shuffner's dots |
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Malaria Rx
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First line - chloroquine
Effective against erythrocyte stages - mefloquine Effective against liver stages and ovale hypnozoite - primaquine |
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Quinolines (MOA, use)
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Block the parasite action of free heme -> hemozoin which is necessary to detoxify the RBC for it to live
Malaria |
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Artemisin derivatives (MOA, use)
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Active against schizont stages
Bind free heme and produces free radicals Use in combination |
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Pyrimethamine (MOA, use)
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Inhibit dihydrofolate reductase
Effective against liver stages but not hypnozoites |
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Malarial antibiotics (3)
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Clindamycin, atovaquone, tetracyclines
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Artemisin derivatives (MOA, use)
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Active against schizont stages
Bind free heme and produces free radicals Use in combination |
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Pyrimethamine (MOA, use)
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Inhibit dihydrofolate reductase
Effective against liver stages but not hypnozoites |
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Malarial antibiotics (3)
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Clindamycin, atovaquone, tetracyclines
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Malaria prophylaxis (4)
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Chloroquine
Mefloquine Atovaquone-proguanil Doxycycline |
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Toxoplasma gondii (transmission , clinical)
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Humans ingest oocytes from cat feces, undercooked meat, transplacental, transplant
Immunocompetent: asymptomatic Immunocompromised: cerebral and ocular cysts Congenital: severe if in 1st trimester |
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Toxoplasma (Dx, Rx)
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Dx - serology, MRI
Rx primary - nothing Rx reactivation - pyrimethamine+sulfadiazine |
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Leishmaniasis (transmission, 3 clinical manifestations)
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Sandfly
Localized cutaneous: red ulcerating papule heals spontaneously Mucocutaneous: erosive only in New World Visceral: amastigotes enter macs -> spiking fevers, hepatosplenomegaly, pancytopenia |
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Visceral leishmaniasis (Dx, Rx)
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Macrophages containing amastigotes
Pentostam (stibogluconate), glucantine |
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Intestinal protozoa (3)
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Entamoeba
Giardia Cryptosporidium |
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Entamoeba histolytica (transmission, clinical, dx, rx)
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Cysts in water
Amebiasis: bloody diarrhea, liver abscess, can disseminate to other organs INVASIVE Dx - stool microscopy shows trophozoites and cysts Rx - metronidazole |
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Giarrdia lambia (transmission, clinical, dx, rx
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Cysts in water
Bloating, abd cramps, diarrhea, can be chronic Dx - trophozoites or cysts in stool (Owl eyes) Rx - Metronidazole |
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Metronidazole (2 uses)
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For protozoa infections
Giaradia Entamoeba |
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Cryptosporidiosis (transmission, clinical, DX, rx)
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Cysts in water
Severe diarrhea in AIDS, watery diarrhea in normal Dx - cysts on acid-fast Rx - prevention by filtering |
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Amastigotes in macrophages
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Leishmaniasis (protozoa)
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