My Micro Part 2, USMLE Flashcards
Rapidly fatal meningoencephalitis
Naegleria fowleri
Tachyzoite on biopsy
T. gondii
Swimming in freshwater lakes; enters via cribriform plate
Naegleria
[Think Nalgene bottle filled
with fresh water containing Naegleria]
Toxoplasma gondii, treatment
Sulfadiazine + Pyrimethamine
Amoebas in spinal fluid
Naegleria fowleri
Diagnosis of trypanosome brucei
Blood smear
Origin of single flagellum of hemoflagellates
Kinetoplast
Location of kinetoplast in trypomastigote
Posterior
Falling leaf motility
G. lamblia
Scrub typhus
R. tsutsugamushi
Leishmania, vector
Sandflies (phlebotomus)
Trypanosoma brucei, vector
Glossina/tsetse fly
Trypanosoma cruzi, vector
Reduviid bug
Hemoflagellate that characteristically assumes a C or U shape in stained blood films
T. cruzi
Has an intracellular amastigote stage in cardiac muscles and other tissues
T. cruzi
Winterbottom sign
T. brucei
Romaña sign
T. cruzi
West African sleeping sickness
T. brucei gambiense
Eastern and central african sleeping sickness
T. brucei rhodesiense
T. brucei gambiense vs T. brucei rhodesiense: More severe
T. brucei rhodesiense
T. brucei, treatment for blood-borne diseases
Suramin
T. brucei, treatment for CNS penetration
Melarsoprol
Tertian malaria
1) P. vivax
2) P. ovale
Quartan malaria
P. malariae
Fever on 1st and 3rd day (every 48 hours)
P. vivax and ovale
Fever every 72 hours
P. malariae
Dormant form in the liver
Hypnozoite
Plasmodia that have dormant forms in liver
P. vivax and ovale
Contain merozoites
Schizonts
Anti-malarial that blocks heme polymerise of plasmodium
Chloroquine
Malaria treatment: Alternative for resistance to Chloroquine
Mefloquine or atovaquone/proguanil
Treatment for life-threatening malaria
IV quinidine or artesunate
Anti-malarial for hypnozoites
Primaquine
Use of these drugs require test for G6PD
1) Artesunate
2) Primaquine
Maltese cross on blood smear
Babesia
Fever and hemolytic anemia; asplenia increases risk of serve disease
Babesia
Dilated cardiomyopathy with
apical atrophy, megacolon, megaesophagus;
T. cruzi
Visceral leishmaniasis
Leishmania donovani
Visceral leishmaniasis is aka
Kala-azar
T/F T. vaginalis can form cysts hence can exist outside human
F, cannot form cysts, cannot exist outside humans
Unilateral periorbital swelling during the acute stage of disease
Chagas disease (Romaña sign)
T. cruzi, treatment
Benznidazole or nifurtimox
Spiking fevers, hepatosplenomegaly, pancytopenia
Visceral leishmaniasis
L. donovani diagnosis
Amastigotes in macrophages
L. donovani, treatment
Amphotericin B
Strawberry cervix
T. vaginalis
Roundworm obstructing ileocecal valve
A. lumbricoides
Roundworm that causes epigastric pain, feeling like peptic ulcer
S. stercoralis
Roundworms that cause anemia
Hookworms
Treatment for roundworms
Bendazoles
Treatment for S. stercoralis
Ivermectin
Treatment for hookworms
Pyrantel pamoate
Larvae enter bloodstream and encyst in striated muscle cells
T. spiralis
Black flies, black skin nodules, black sight (river blindness)
Onchocerca volvulus
Treatment for O. volvulus
Ivermectin
Deer fly, horse fly, mango fly
Loa loa
Elephantiasis
W. bancrofti
Allergic reaction to microfilaria
O. volvulus
Swelling in skin, worm in conjunctiva
Loa loa
W. bancrofti, vector
Female mosquito
Visceral larva migrans
Toxocara canis
Blockage of lymphatics by W. bancrofti becomes symptomatic when
9 mod-1 year after bite
Treatment for Loa loa and W. bancrofti
DEC
Nematode routes of infection: Ingested
Enterobius, Ascaris, Toxocara, Trichinella
[You’ll get sick if you EATT these!]
Nematode routes of infection: Cutaneous
Strongyloides, Ancylostoma, Necator
[These get into your feet from the SANd.]
Nematode routes of infection: Bites
Loa loa, Onchocerca volvulus, Wuchereria bancrofti
[Lay LOW to avoid getting bitten.]
Ingestion of larvae from raw freshwater fish causes infection
D. latum
Means by which T. solium is acquired causing INTESTINAL infection
Ingestion of encysted larvae in undercooked pork
Cysticercosis, neurocysticercosis
T. solium
Means by which T. solium is acquired causing cysticercosis and/or neurocysticercosis
Ingestion of eggs
Intermediate host of E. granulosus
Sheep
Cestode: Vitamin B12 deficiency
D. latum
Hydatid cyst
E. granulosus
Done prior to removal of hydatid cyst to prevent anaphylaxis from released daughter cysts from liver
Injection with ethanol or hypertonic saline
Treatment for cestodes except E. granulosus
Praziquantel
Treatment for E. granulosus
Albendazole
Treatment for neurocysticercosis
Albendazole
Host of schistosoma
Snails
Mode of transmission of schistosoma
Penetration of skin
Schistosoma: Hepatosplenomegaly
S. mansoni
Schistosoma: SCC of bladder with chronic infection
S. haematobium
Schistosoma: Pulmonary hypertension with chronic infection
S. haematobium
Schistosoma: Lateral spine
S. mansoni
Schistosoma: Terminal spine
S. haematobium
Treatment for Schistosoma infection
Praziquantel
Treatment for Clonorchis sinensis
Praziquantel
Biliary tract disease, cholangiocarcinoma
Clonorchis sinensis
Brain cysts, seizures
Taenia solium (neurocysticercosis)
Microcytic anemia
Ancylostoma, Necator
Myalgias, periorbital edema
Trichinella spiralis
Portal hypertension
Schistosoma mansoni, Schistosoma japonicum
Megaloblastic anemia
D. latum
Viral genetics: Exchange of genes between 2 chromosomes by crossing over within regions of significant base sequence homology.
Recombination
Viral genetics: When viruses with segmented genomes (e.g., influenza virus) exchange genetic material. For example, the 2009 novel H1N1 influenza A pandemic.
Reassortment
Viral genetics: Human flu, swine flu, bird flu
Reassortment
Viral genetics: When 1 of 2 viruses that infect the cell has a mutation that results in a nonfunctional protein
Complementation
Viral genetics: Hep D and Hep B
Complementation
Viral genetics: Occurs with simultaneous infection of a cell with 2 viruses
Phenotypic mixing
Live attenuated viral vaccines
1) Smallpox
2) Yellow fever
3) Rotavirus
4) VZV
5) Sabin polio
6) MMR
7) Influenza (intranasal)
[Live! See SMALL YELLOW ROTATING CHICKENS get vaccinated with SABIN and MMR! It’s INcredible!
T/F Live attenuated vaccines can be given to HIV-positive patients who do not show signs of immunodeficiency
T
Killed viral vaccines
RIP Always Rabies Influenza Polio (Salk) HAV
Viral vaccines made of viral subunits
1) HBV
2) HPV
The only ssDNA DNA virus
Parvovirus
The only dsRNA RNA virus
Reovirus
T/F Naked nucleic acids of negative strand ssRNA and dsRNA are not infectious
T, require polymerases
The only DNA virus that does not replicate in the nucleus
Poxvirus
The inly RNA viruses that does not replicate in the cytoplasm (2)
1) Influenza
2) Retroviruses
Naked viruses
[Give PAPP smears and CPR to a naked Heppy (hippy).] [PAPP=DNA; CPR=RNA] Papilloma Adeno Parvo Polyoma Calici Picorna Reo Hepe
Enveloped viruses acquire their envelopes from
Plasma membrane when they exit from cell
The only enveloped virus that acquires its envelope from nuclear membrane
Herpesvirus
All DNA viruses are linear except
1) Papilloma (circular, supercoiled)
2) Polyoma (circular, supercoiled)
3) Hepadna (circular, incomplete)
All DNA viruses are icosahedral except
Poxvirus
Virus that carries its own DNA-dependent RNA polymerase
Poxvirus
Largest DNA virus
Poxvirus
Smallest DNA virus
Parvovirus
Oral (and some genital) lesions, spontaneous temporal lobe encephalitis, keratoconjunctivitis
HSV-1
Genital (and some oral) lesions
HSV-2
Chickenpox, zoster (shingles)
VZV (HHV-3)
Mononucleosis
EBV (HHV-4)
Infection in immunosuppressed patients (AIDS retinitis)
CMV
Burkitt lymphoma
EBV
Transplant recipients
CMV
Roseola (exanthem subitum)
HHV-6
Hodgkin lymphoma
EBV
Kaposi sarcoma
HHV-8
Nasopharyngeal carcinoma
EBV
Not a retrovirus but has reverse transcriptase
HBV
Hepatitis: Hepadnavirus
HBV
Hepatitis: Picornavirus
HAV
Conjunctivitis —“pink eye”
Adenovirus
Acute hemorhhagic cystitis
Adenovirus
Aplastic crises in sickle cell disease, “slapped cheeks” rash in children
Parvovirus B19
Transplant patients, commonly targets kidney
BK virus
Erythema infectiosum/Fifth disease
Parvovirus B19
RBC destruction in fetus leads to hydrops fetalis and death, in adults leads to pure RBC aplasia and rheumatoid arthritis–like symptoms
Parvovirus B19
Milkmaid blisters
Cowpox
Most common cause of sporadic encephalitis,
HSV-1
HSV-2, latent in
Sacral ganglia
Most common complication of shingles
Post-herpetic neuralgia
Fever, hepatosplenomegaly, pharyngitis, and lymphadenopathy (especially posterior cervical nodes)
Mono (EBV)
EBV infects B cells through this CD
CD21
Atypical lymphocytes in EBV infection
Reactive cytotoxic T cells
Diagnosis of EBV
Monospot test for heterophile antibodies
Owl eye inclusions
CMV
CMV are latent in
Mononuclear cells
Roseola transmission
Saliva
Dark/violaceous plaques or nodules representing vascular proliferations, seen in HIV/AIDS and transplant patients
HHV-8 (Kaposi sarcoma)
HHV-8 mode of transmission
Sexual contact
Multinucleated giant cells on tzanck smear
HSV 1 and 2, VZV
Colorado tick fever
Reovirus (Coltivirus)
1 cause of fatal diarrhea in children
Rotavirus
Aseptic (viral) meningitis
1) Echovirus
2) Coxsackie virus
3) Poliovirus
4) Mumps
“Common cold”
Rhinovirus
Herpangina (mouth blisters, fever)
Coxsackie virus
Hand, foot, and mouth disease; myocarditis; pericarditis
Coxsackie virus
Hepatitis: Hepevirus
HEV
Hepatitis: Flavivirus
HCV
T-cell leukemia
HTLV
Retroviruses (have reverse transcriptase)
1) HIV
2) HTLV
“Common cold” and SARS
Coronavirus
Orthomyxovirus
Influenza
Paramyxovirus
[PaRaMyxovirus]
Parainfluenza
RSV
Measles, Mumps
Bronchiolitis in babies
RSV
Filoviruses
Ebola/Marburg hemorhhagic fever
Hepatitis: Delta virus
HDV
Must transcribe ⊝ strand to ⊕. Virion brings its own RNA-dependent RNA polymerase.
Negative-stranded viruses
Segmented viruses
[BOAR] Bunya Orthomyxo Arena Reo
All picornaviruses are enteroviruses (decal-oral spread) except
Rhinovirus (acid labile)
Picornaviruses
[PERCH; PicoRNAvirus, all are RNA viruses] Poliovirus Echovirus Rhinovirus Coxsackievirus HAV
Reservoir of yellow fever virus
Monkey or humans
Most important global cause of infantile gastroenteritis
Rotavirus
Black vomitus
Yellow fever virus
Diarrhea in day care centres and kindergartens
Rotavirus
Councilman bodies (eosinophilic apoptotic globules) on liver biopsy
Yellow fever virus
Influenza: Promotes viral entry
Hemagglutinin
Influenza: Promotes progeny virion release
Neuraminidase
Genetic/Antigenic SHIFT vs DRIFT: Causes pandemics
Shift
Genetic/Antigenic SHIFT vs DRIFT: Causes epidemics
Drift
Genetic/Antigenic SHIFT vs DRIFT: Reassortment of viral genome segments, such as when segments of human flu A virus reassort with swine flu A virus.
Shift
Genetic/Antigenic SHIFT vs DRIFT: Random mutation in hemagglutinin or neuraminidase genes.
Drift
T/F Sudden shift is more deadly than gradual drift
T
Rubella: Family
Togavirus
Croup: seal-like barking cough)
Parainfluenza
German measles
Rubella
All contain surface F (fusion) protein, which causes respiratory epithelial cells to fuse and form multinucleated cells.
Paramyxoviruses
Fever, postauricular and other lymphadenopathy, arthralgias, and fine rash
Rubella
Inspiratory stridor; Narrowing of upper trachea and subglottis leads to characteristic steeple sign on X-ray
Croup/acute laryngotracheobronchitis
Measles
Rubeola
Prodromal fever with cough, coryza, and conjunctivitis
Measles
Mild disease in children but serious congenital disease (a ToRCHeS infection)
Rubella
“blueberry muffin” appearance, indicative of extramedullary hematopoiesis
Rubella
Koplik spots
Measles
Spread of maculopapular rash of measles
From head and neck downward
Parotitis, orchitis, aspetic meningitis
Mumps
[Mumps makes your parotid glands and testes as big as POM-poms]
Vitamins given in measles infection to educe measles
mortality in malnourished or vitamin-deficient children
Vitamin A
Lymphadenitis with Warthin-Finkeldey giant cells (fused lymphocytes)
Measles
Subacute sclerosing panencephalitis (SSPE)
Measles
Bright red spots with blue-white center on buccal mucosa that precede the measles rash by 1–2 days.
Koplik spots of measles
Negri bodies commonly found in Purkinje cells of cerebellum and in hippocampal neurons
Rabies
Rabies virus bind to what nerve receptors
Ach
A filovirus that targets endothelial cells, phagocytes, hepatocytes
Ebola
