Bugs!

Front 1

Candida Albicans

Back 1

Dz= Thrush, vaginitis, esophagitis, systemic infection (immunocompromised)
Path= Normal flora overgrowth; cutaneous looks red/macerated; occurs in creases/folds (warm/moist environ.); Vaginitis from Abx. Esophagitis=> substernal burning pain. Systemic=> retinitis.
Dx= Creamy white exudate w/ reddish base (can't scrape off w/ tongue blade); KOH prep shows pseudohyphae/budding yeast. Blood culture if systemic.
Tx= Nystatin mouthwash (oral thrush), fluconazole, imidazole cream. If systemic; ampho B or fluconazole PO.
Prev= Difficult- b/c is normal flora

Front 2

Entamoeba Histolytica

Back 2

Dz= Amebic dysentery, liver abscess.
Path= Fecal-oral. Cyst ingested-> becomes trophozoite in ileum... then either: asymptomatic carriage (trophozoite to 4 nuclei cyst in stools: binary fission), invasive amebiasis (trophozoite to portal circulation to liver and abcess forms), intestinal amebiasis (trophozoite to local necrosis and dysentery: bloody diarrhea)
Dx=Stool. trophozoite w. ingested RBCs (active) or 4 nuclei cyst (carrier)
Tx= Metronidazole (active state), drainage (hepatic abscess), iodoquinol or diloxanide furoate (carrier state)
Prev= BOIL it! Chlorination doesn't kill.

Front 3

Rabies (Rhabdoviridae lyssavirus)

Back 3

Dz= Rabies (dysphagia, encephalitis w/ seizures/hydrophobia, FATAL!)
Path= Bullet shaped glycoprotein spikes bind ACh receptors. Infects many mammals- to humans via animal bite. Gives CYTOPLASMIC INCLUSIONS of neurons in brainstem/brain. Death from resp center dysfunc.
Dx=Negri bodies in neurons/infected cells. PCR for viral RNA, serology
Tx= Wash wound immediately! HRIG (Human Rabies Immune Globulin) antibodies for passive immunity. Human diploid cell vaccine (live attenuated virus) to give post bite.
Prev= Human diploid cell vaccine (live virus) immunize animals.
"foaming at mouth" from inability to clear saliva from dyshphagia.
SS-non-segmented RNA, helical nucleocapsid, enveloped.

Front 4

HSV 1/HSV 2

Back 4

Dz=Genital herpes, gingivostomatitis, herpes labialis (cold sores)
** HSV-2 is MOST COMMON CAUSE of viral encephalitis in INFANTS**
Path= only human resevoir. Spit=> invades mucous membrane => local 1` infection=> asymptomatic=> vasicular lesions that ulcerate.
1` infection gone in 2-3 wks; virus travels up local sensory nerves to sensory ganglion cell body (latent infection). Stress=> viral reactivation, virus from ganglion to nerve ending=> recurrent local infection.
** During pregnancy: Can travel to placenta or during delivery. Infected child= congenital defects, abortion, neonatal encephalopathy.
Dx= PCR. Multinucleate giant cells on Tzank smear of lesions ("Tzank god i don't have herpes!"), eosinophilic Cowdry intranuclear inclusion bodies on skin biopsy.
Tx= Acyclovir
Prev= No glove, no love. C-sec if preg.

Front 5

Coccidioides

Back 5

Disease: Coccidioidomycosis- mild/asympto pneumonia (if immuno-comp) or systemic infection (immunocompromised)
Path: Spores from SW USA inhaled. become spherules w/ infective endospores-- local lung infection. IF immunocompr- pnuemonia, systemic (GRANULOMAS throughout body... can kill you!)
Dx= Serology, Culture (hyphae at 25 degrees; single cell at 37 degrees). Intradermal injection will cause DTH if have exposure hx.
Tx= supportive, Ampho B if systemic w/o CNS. Fluconazole if w/ CNS.
Prev= No SW travel!
"HINT: Cock a gun in the SW, Mr. Fungus shoots bones, CNS, skin, lungs.)

Front 6

Giardia Lamblia

Back 6

Disease: Non-bloody, fatty diarrhea (asympt carrier in 5%)
Path: Fecal-oral cyst ingestion (contaminated water). Cyst to trophozoite in duodenum (no invasion= no blood) Attached via suction disk. microvilli damage= inflammation/malabsorption/gas!
Dx= Stool sample: trophozoites (kite w/ two nuclei and 4 prs flagella) and cysts. Giardia immunoassay (ELISA); string test (historical)
Tx- metronidazole
Prev- good sanitation; don't drink dirty water (boil it or iodine it)

HINT: classic story= young camper drinks out of stream around beavers/rodents; or day-care centers.

Front 7

Staphylococcus Aureus

Back 7

Disease: skin/subq, respiratory, acute endocarditis (esp. IVDUs), meningitis, osteomyelitis, septic arthritis, bacteremia, sepsis, UTIs; TOXIN- TSS (TSST-1= superantigen; gives excess IL-1/TNF-a, scalded skin syndrome (Ritters dz in newborns), food poisoning (toxin; abrupt, self-limited; 8-24 hr. nausea).
Path: Colonize-> overgrowth via:
Protein A (Fc portion of IgG)
Coagulase (fibrin coat around orgs)
Hemolysins, leukocidins
Teichoic acid (attached fibronectin on mucosa)
--Neutrophils to infection-> purulent abscesses form, skin/subq infections, pneumonia.
Blood invasion via:
Hyaluronidase,
Staphylokinase
Lipase
DNAase
Dx: Gram pos cocci in clusters, catalase +, coagulase +, betahemolytic w/ gold pigment on mannitol salt agar.
Tx: MSSA: methicillin, dicloxacillin; MRSA: vancomycin
Prev: wash hands, good food storage.
*** Pts w/ chronic granulomatous dz (impaired neutrophil func) are at increased risk!
Cytotoxins
PV leukocidin

Front 8

Borrelia Burgdorferi/ Ehrlichia

Back 8

Disease: Lyme Dz
Stage 1- Erythema chronicum (spreading annular lesion)
Stage 2- CNS (bell's palsy, aseptic meningitis, peripheral neuropathy); CV (carditis, myopericarditis, av block); skin (2ary annular lesions) joints (migratory arthritis) eye (conjuctavitis, panophthalmitis (w/ or w/o retinal detach)
Stage 3= chronic arthritis (HLA-DR1; HLA DR4), encephalopathy, acrodermatitis chronicum atrophicans.
Path: Carried in rodents; Ixodes tick carries to humans-> spirochetes disseminate.
(stage 1= local infection, bacteria spread); stage two; disseminated spirochetes proliferate and give inflamm damage; stage three: persis infection- inflamm damage to all and local areas of skin atrophy (acrodermatitis chronicum atrophicans)
Dx= spirochete on skin biopsy- motile under dark field. (or ELISA, western blot, clinical dx, CSF= 100 lymphs, inc protein, normal glucose.
Tx= doxycycline or amoxacillin for stage 1; ceftriaxone for later stages
Prev= Tick checks.