Micro Flashcards
BCG vaccine
Variable efficacy in studies
Some studies say protects against miliary and TB meningitis
Given to at risk infants
Mycobacterium bovis
Mycobacterium avium-intracellulare
Bad for AIDS patients
Mycobacterium marinum
Fishtanks
Single clusters papules/plaques
Leprosy
Aka Hansen’s disease.
Mycobacterium leprae and M. lepromatous
Skin depigmentation, sensory neuropathy
Tuberculoid form
Lepromatous form (worse)
Tends to affect peripheries (cooler temp)
Armadillo natural reservoir
Caseating granuloma differential
TB
Fungus (especially if they are from Minnesota)
Pneumonia
Inflamm alveoli
Lobar, interstitial, or broncho-pneumonia
Fever and chills, productive cough with yellow-green sputum, pleuritic CP and tachypnea, decreased breath sounds, dullness to percussion, elevated WBC count
Lobar pneum
Consolidation entire lobe on CXR
MCC: S. pneum (95%) and Kleb pneum
Stages:
- Consolidation
- Red hepatization
- Grey hepatization
- Resolution
Klebsiella pneumoniae as cause pneumonia
Enteric flora….so aspirated somehow.
Think drunks and physically disabled
CURRENT JELLY SPUTUM
Strep pneum as cause pneumonia
MCC community-acquired pneum and secondary pneum
Rusty colored sputum
Secondary pneumonia
Bacterial pneumonia superimposed on viral URTI
S. aureus as a cause pneumonia
2nd MCC secondary pneum.
Oft complicated by abscess or empyema (NB coagulase positive)
Pseudomonas aeruginosa as cause pneum
Associated with CF patients
Moraxelle catarrhalis as a cause of pneum
Assoc with COPD
H. influenzae as cause pneum
Comm cause secondary pneum and superimposed on COPD (smokers)
Legionella pneumophila as cause pneumonia
Community acquired…water source
Superimposed on COPD or immunocompromised
Silver stain
Causes bronchopneum
S aureus H. flu P. aerug M. catarrhalis Legionella
Bronchopneum on CXR
Patchy consolidation around bronchioles. Oft multifocal and B/L
Interstitial pneumonia
=Atypical pneum, "walking pneumonia" Relatively mild upper resp sxs **M pneum, Chlamydia pneum College dorms, military recruits Influenza in elderly, RSV in infants, Coxiella in farmers
Q fever
Coxiella burnetti
Atypical pneum with high fever
Farmers/vets…spores from ticks on cattle or in cattle placentas
Why is Coxiella unique?
Although Rickettsial organism, causes pneum, does not require arthropod vector, and does not produce skin rash
(As opposed to other rickettsial diseases)
Chlamydia psittaci
Birds.
RTI + AIDS
PCP
TB
Cryptococcus
RTI + neutropenia
Aspergillus/fungi
RTI + Splenectomy
Encapsultaed orgs: SHiN
Abx mild-mod CAP
Amoxicillin or macrolide
Abx: mod-severe CAP
Co-amoxiclav + clarithromycin
Macrolides
erythromycin, clarithromycin
Inhibit 50S subunit
Aminoglycosides
"GNATS" Gentamicin Neomycin Amikacin Tobramycin Streptomycin
Inhibit 30S subunit
Abx: Hosp-Acquired pneum
Cipro + Vanco
Abx: aspiration pneum
Cefuroxime + metronidazole
Abx: legionella
Macrolide + Rifampicin
Abx: pseudomonas pneum
Piperacillin + tazobactam
Abx: MRSA
Vancomycin
STIs with discharge
Gonorrhea Chlamydia Trichomonas Candida BV
STIs with ulceration
Syphilis HSV LGV Chancroid Donovanosis
STIs with Rashes, lumps, growths
Scabies
Pubic lice
Genital warts (HPV)
Molluscum contagiosum
PAINFUL genital ulcers
Herpes>chancroid
Painless genital ulcer
Syphilis>LGV and granuloma inguinale
Pregnant + gonorrhea
Opthalmia neonatorum
Tx: gonorrhea
250mg IV ceftriaxone
Dx-chlamydia
NAAT
Tx-chlamydia
Azithromycin 1g (Can do 7d doxy but less compliance)
LGV
Lymphatic infection, Chlamydia trachomatis L1-L3
Developing world, MSM developed
Tx: doxy 100mg BD 21d
Syphilis
- bug
- Dx
Treponema pallidum
Majority cases in those with HIV
Dark-ground microscopy
VDRL, RPR
Primary syphilis
Ulcer
Secondary syphilis
Systemic sxs, rash
Can have neuro involvement
Tertiary syph
Gumma (granuloma), 2-20 yrs later
Aortitis
Neurosyph/tabes dorsalis, argyll robertson pupils
Tx-syph
IM Ben-pen
Jarisch-Heimer reaction
Fever, HA, myalgia in response to Abx for syph
Congenital syphilis
HSM, rash, fever, neurosyph, pneumonitis, hutchinson teeth
Chancroid
H. ducreyo (G-)
Tropical
Mult painful ulcers
Donovanosis
Granuloma inguinale Klebsielle granulomatis (G-) Africa, India, Aboriginal communities Giemsa stain Tx-azithro
Trichomonas
- cause
- Dx
- Tx
Trichomonas vaginalis
Dx-wet prep microscopy
Tx-metronidazole
BV
Gardnerella, decreased lactobacilli Increased pH Fishy odor, discharge Whiff test (KOH prep), Gram stain, clue cells Tx: metronidazole
Candidiasis
- sxs
- associations
- Tx
Thick white “cottage cheese” discharge, extremely itchy
May be associated with immunodeficiency, diabetes
Fluconazole
Molluscum contagiosum
dsDNA pox virus Hands and feet in children Adults-genital lesions, sexual contact In adult=HIV until proven otherwise. Giant lesions if immunocompromised Tx-trauma, cryotherapy
Genital warts
HPV 6,11 Oft asxs. Warts can recur after tx Incubation: 3/52-8/12 Home tx: podophyllin cream Clinic tx: cryotherapy, imiquimod
Superficial fungal infxn-diagnostic tool
Wood’s lamp
Tinea versicolor
Caused by malassezia furfur.
Skin depigmentation
Dx candida
Culture, mannan Abs
Also beta-D-glucan
Dx-aspergillus
ELISA, PCR, beta-glucan
Dx-cryptococcus
Cryptococcal antigen in serum/CSF
TB
do this later
Meningitis-definition
Inflamm process of meninges and CSF
Meningoencephalitis-definition
Inflamm process of meninges and brain parenchyma
Routes of entry for CNS infections
Hematogenous spread
Direct implantation (instrumentation)
Local extension (secondary to infxn)
PNS to CNS, e.g. polio
Meningitis-Signs and Sxs
Fever, HA, stiff neck, brain fn disturbance
Causative agents-meningitis
N. men S. pneum H. flu TB Cryptococcus
Encephalitis-signs and symptoms
Brain function disturbance
Encephalitis-causes
HSV
Rabies, arboviruses, trypanosoes, prions, amoeba
Myelitis
Disturbance nerve transmission
Poliovirus
Neurotoxins
Paralysis, rigid (tetanus) or flaccid (botulism)
TB meningitis
Immunosuppressed pts
meninges and basal cisterns of brain and spinal cord
Can result in tuberculous granulomas, tuberculous abscesses
DON’T give steroids…call a specialist.
Aseptic meningitis
Most common CNS infection HA, stiff neck, photophobia Non-specific rash No white cells and normal gluc in CSF Coxsackie B and echoviruses =80-90% Self-limiting and resolves in 2/52
Reportable GI infections
Campylobacter Salmonella Shigella E. coli O157:H7 Listeria Norovirus
Secretory diarrhea
No fever/low grade
No WBCs in stool
V cholerae
ETEC, EPEC, EHEC
Inflammatory diarrhea
Fever
WBC in stool (neutrophils)
C. jejuni
Shigella spp
Non-typhoidal salmonella
EIEC
Enteric fever
Gastroenteritis:
Fever
WBC in stool (mononuclear cells)
Typhoidal salmonella (S typhi, S paratyphi)
Yersinia spp
Brucella spp
Bloody diarrhea-gastroenteritis causes
Campylobacter, E. coli, shigella, salmonella (non-typhoidal), vibrio parahemolyticus
Cholera
Need high infective dose
Kills esp children and those on PPIs
Mimics adenylyl cyclase
C. perfringens food poisoning
Normal flora of colon, but not small bowerl–where enterotoxin acts (superantigen)
8-16 hr incubation
Watery diarrhea, crmaps, little vomiting lasting 24 hrs
C. difficile
Pseudomembranous colitis
Abx related–mainly cephalosporins, cipro, clindamycin
Forms pseudomembranous colitis ->toxic megacolon.
Tx: metronidazole, vanco, stop other unnec Abx, avoid PPIs if poss
Listeria monocytogenes
Outbreaks febrile gastroenteritis
Beta hemolytic TUMBLING MOTILITY
Watery diarrhea, cramps, HA, fever, little vomiting
Perinatal infxn: prem, neonatal bacteremia/meningitis
Tx: ampicillin, ceftriaxone, cotrimoxazole
Vibrio parahemolyticus
Ingestion raw/undercooked seafood
Major cause of diarrhea in Japan/Caribbean
Campylobacter
Curved, comma, or S shaped Microaerophilic C. jejuni grows at 42 C Oxidase positive Self limiting but sxs can last weeks Only tx if immunocompromised (macrolide)
Vibrio cholerae
Contamination water and food from human feces
Colonization small bowel and secretion enterotoxin A/B causing persistent activation adenylate cyclase
Rice water stools without inflamm cells
Giardia lamblia
Trophozoite
Pear shaped
Ingestion of cyst from fecally contaminated water/food
Protein and fat malabsorption–foul smelling non-bloody diarrhea, cramps, flatulence, no fever
Dx: stool micro, ELISA, “string test”
Tx-metronidazole
Cryptosporidium parvum
Infects jejunum
Severe diarrhea in immunocompromised
Oocysts seen in stool
Tx: reconstitution immune system
Rotavirus
dsDNA
Replicates in mucosa small intestine
Secretory diarrhea, no inflamm
“ROTA=Right Out The Anus”
By age 6, most have Abs of at least one type
Two exposures result in lifelong immunity
Adenovirus
Non-bloody diarrhea. Usu
Hepatitis A
Fecal-oral transmission Often subclinical Tourists, MSM, sewage workers Rise in ALT Vaccine to MSM, travelers
Hepatitis B
Chronic carrier if >6/12
2-6mo incubation
G+ rods
Clostridium Corynebacterium Listeria Bacillus Mycobacteria
G+ branching filamentous
Actinomyces
Nocardia
Alpha hemolysis
S. pneum
Strep viridans
Beta hemolysis
S pyogenes
S agalactiae
Group B strep
S pyogenes
Group A strep
S. agalactiae
Gamma hemolysis
Enterococci
S. pneum is most comm cause of which diseases?
"MOPS" Meningitis Otits media Pneumonia Sinusitis
Corynebacterium diphtheriae
Causes diphtheria: pseudomembranous pharyngitis, LAD, myocarditis, arrhythmias.
Toxoid vaccine
Gram negative rods
H. influenzae
Pasteurella
Brucella
Bordetella pertussis
Gram negative–comma shaped
C. jejuni
V. cholerae
H. pylori
Gram neg rods
Klebsiella E coli Enterobacter Serratia Shigella Salmonella Proteus Yersinia Pseudomonas
Legionnaire’s disease
Legionella pneumophila
Severe pneumonia, fever, GI and CNS symptoms
Hyponatremia
Pontiac fever
Legionella pneumophila
Mild flu-like illness
Pseudomonas aeruginosa
Grape-like odor
Wound/burn infections, sepsis, external otitis (swimmer’s ear), UTI, drug use, diabetic osteomyelitis
Typhoid
Salmonella typhi
Rose spots on abdo, fever, HA, diarrhea
Can remain in GB as carrier state
Yersinia
Mesenteric adenitis, resembling Crohn’s or apendicitis
H pylori
Urease positive, creating alkaline environment
RF for peptic ulcers, gastric adenocarcinoma, lymphoma
Spirochetes
Borrelia
Leptospira
Treponema
Bartonella
Cat scratch disease
Borrelia burgdoferi
Lyme disease
Borrelia recurrentis
Relapsing fever
Ehrlichia chafeensis
Ehrlichiosis
Lone Star ticks
Fransisca tularensis
Tularemia
Rabbits
pasteurella multocida
Cellulitis
Animal bites
Treatment for all rickettsial diseases
Doxycycline
Mucor, Rhizopus spp
Mucormycosis in DKA, leukemic pts
Palms and soles rash-ddx
Rocky Mountain spotted fever
Coxsackie A (hand, foot, and mouth)
Secondary syphilis
Rickettsial diseases
Rocky Mountain spotted fever Typhus Ehrlichiosis Anaplasmosis Q fever
Herpes viruses
HSV1, 2 EBV VZV CMV HHV6-roseola HHV8-Kaposi's
DNA viruses
Hepadna Herpes Adeno Pox Papilloma Polyoma Parvo
All double stranded except parvo
HBsAg
HBV infection
anti-HBs
Immunity to HBV
HBeAg
Active viral replication, infectivity
Anti-HBeAg
Low transmissibility
Marker immunization to HBV
anti-HBs
Bloody diarrhea
Campylobacter EHEC EIEC Shigella Salmonella E. histolytica Yersinia enterocolitica
Watery diarrhea
C diff C perfringens ETEC Protozoa V cholerae Viruses (noro, rota)
Positive nitrites on urine dip
Gram negative bacteria
Positive leukocyte esterase on urine dip
Bacteria
ToRCHeS infections
Cross placenta
Toxo Rubella CMV HIV, HSV2 Syphilis
Blueberry muffin rash in neonate
Congenital rubella, congenital CMV
Abx, antivirals, antifungals to avoid in pregnancy
Sulfonamides Aminoglycosides Fluoroquinolones Clarithromycin Tetracyclines Ribavirin Griseofulvin Chloramphenicol
Flying saucer cysts on methensmine silver stain
PCP
Which bug causes hyponatremia
Legionella
Tumbling motility
Listeria
Entamoeba histolytica
Flask shaped ulcers in colon, cecum
Dysentery, weight loss, liver abscess
HHV-8
Kaposi’s
Primary effusion lymphoma
Castleman’s
HIV treatment regimen
Two NRTIs
One NNRTI or PI
Phialophora verrucosa
Saprophyte on rooting wood.
Warty lesion resembling cauliflower
Tinea corporis
Ringworm
Cerebral Negri bodies (inclusion bodies)
Pathognomonic for rabies
Fite stain
Leprosy
Acyclovir-mech
Guanosine analogue.
Phosphorylated by viral thymidine kinase
When do infants get Men C vaccine?
3m, 4m, 12m
When do infants get PCV?
2m, 13m
Visceral leishmaniasis
L. Donovani, l. Infantum Kala-azar Fever, splenomegaly, can get hepatomegaly. Can get blackened skin/hyperpigmentation May closely resemble malaria
Cutaneous leishmaniasis
L. Major, L. Tropica
Itchy papule that becomes ulcer with raised edges.
Heals within 8m, leaving depigmented scar.
Most common type leishmaniasis
Mucocutaneous leishmaniasis
L. braziliensis
Destructive and disfiguring facial lesions.
May start in same way as cutaneous but years later, ulceration in mucous membranes and mutilation.
Novy-macneal-michelle medium
Leishmaniasis
First Hep B antibody to appear after infection
HBsAg
C diff treatment
14 days metronidazole PO
Can repeat if doesn’t work
Then use vanco
Vanco if severe, ileus
Sporadic CJD
"Demented LAMB": Dementia around age 65 LMN signs Akinetic mutism Myoclonus Cortical blindness
EEG for dx
Test for variant CJD
Tonsillar biopsy
LP in CJD
Looks for protein 14-3-3
Features if variant CJD
Younger (ave age 26)
Median survival longer (14m versus 4m)
Psych before neuro features
CSF findings: bacterial, viral, TB meningitis
Bacterial has neutrophils, increased protein, decreased glucose
Viral has high lymphos
TB like viral but very high protein
Spontaneous bacterial peritonitis
Boozers with ascites and signs infection
MCCs are E. coli, enterococci
Tx with cefotaxime or third gen ceph
Significant factor in whether or clears HCV
Virus genotype.
Type 1 harder to clear
Sleeping sickness
Africa
Tsetse fly
Trypanosomes
When crosses BBB, causes neuro sxs like disturbed sleeping patterns
Tx with pentamidine, suramin
Trypanosoma brucei gambiense
West and central Africa.
Gradual onset
More common
Trypanosoma brucei rhodiense
South and East Africa. Rapid onset (weeks to months)
Tx-Chagas
Benzimidazole or nifurtimox
Plasmodium knowlesi
SE Asia/Borneo
Daily fever
Sporozites
What mosquito injects into bloodstream
Merozites
Sporozites that have multiplied in liver Contain shizonts ("diamond rings")
Hypnozoites
Dormant forms in liver
Vivax, oval
Tx-falciparum
Admit Quinine and doxy 5-7 days Or Co-artem 3 days Or Malarone 3d
Malarone
Atorvaquone-proguanil
Tx-non-falciparum malaria
Chloroquine (kills RBC parasites) Then primaquine (kills hynozoites)
Maurer’s clefts
Seen in falciparum
Schuffner’s dots
Seen in Vivax, ovale