Infectious Disease Flashcards
Botulism
Bacterial Diseases
Clostridium botulinum, Gram+ anaerobic bacilus,
canned food products
Sxs
- muscle weakness, difficulty swallowing
- respiratory paralysis “floppy babies”
- diplopia, eyelid drooping,
Dx
- Toxin assays or electromyography
- Foodborne botulism - C. botulinum toxin in stool or serum
- Would botulism - serum toxin or anaerobic wound
Tx
- Equine heptavalent antitoxin
- Wait until baby is 12 mos old before givine honey
- Heat 120 degrees for 30 mins
Campylobacter jejuni
Bacterial Disease
MCC acute bacterial diarrhea
contaminated poultry
Sxs
- fever, watery-bloody diarrhea, abd pain
- post campylobactr Guillain-Barre syndrome & reactive arthritis possible
Dx
- Skirow agar culture at 42 degrees (CAMPing in the heat)
- Comma or S shaped w/ polar flagella a
Tx
- azithromycin or FQ
Candidiasis
Fungal Disease
Common in opportunistic infx, C albicans
Dx - KOH smear
Esophageal candidiasis
- linear erosions on endoscopy, tx with flucanozole
Vaginal Candidiasis
- vulva itching, erythema, white curdy dc
- tx w/ miconazole cream x7d or fluconazole (diflucan) 150mg PO x1
Oral thrush
- friable white plaques that bleed if scraped
- tx w/ nystatin
Intertrigo
- moist macerated areas, pruritis rash - Beefy red erythema w/ distinct scalloped borders and satellite lesion
- Tx w/ clotrimazole, ketoconazole, miconazole
Cholera
Bacterial Disease
Undercooked shellfish or contaminated water
Vibrio colerae, G-, oxidase positive, comma shaped bacteria
Sxs
- rice water diarrhea
Dx
- Stool culture
- electrolytes, BUN, and Cr measured
Tx
- _Fluid replacement ***_
- Doxy, azithromycin, furazolidone, Bactrim, ciprofloxacin
Congenital Varicella Zoster
Prenatal transmission Disorders
If infx in first 28 wks => congenital varicella syndrome + risk of developing herpes zoster in first 4 years of life.
Dx - PCR of fetal blood or amniotic fluid for VZV DNA + US
Tx - VariZIG immune globulin for non-immune preg for exposure to VZV w/in 10d
Cryptococcosis
Fungal Disease
Cryptococcus neoformans, common in AIDs and IMC
From pigeon/bird droppings transmitted through inhalation
Sxs:
- Meningoencephalitis - MCC fungal menigitis
- AMS, HA, meningismus
- Pna - cough w/ little sputum + pleuritic chest pain
Dx
- CSF (incr protein, decr glucose) and serum
- indian ink stain** showing cysts
- CT ror MRI if + cryptococcoma
Tx
- Amp B + Flucytosine for 2 wks then Fluconazole x 10 wks
- prophy CD4 < 100 with Fluconazole
Cytomegalovirus
Viral Diseases
DS linear DNA in herpes family HHV5
- Similar to infectious mononucleosis but no pharyngitis
- pneumona and inflammation of retina in IMC and transplant pts CD4 <50
- one of the ToRCH
Dx
- Tissue biopsy with owl’s eyes inclusion
Tx
- Ganciclovir, valganciclovir, foscarnet, cidofovir
- Initial IV then maintenance
Diphtheria
Bacterial Diseases
URI w/ thick gray pseudomembrane in the throat that bleeds if scrapped
unvaccinated (2,4,6, and 15-18 mos; booster at 4-6 yo)
Sxs
- neck swelling = enlarged cervical lympadenopathy (bull neck)
- pharyngitis
- low grade fever
- systemic toxicity + hoarseness, palatal paralysis, stridor
Dx
- PCR - rapid detection
- Culture
Tx
- Diphtheria antitoxin
- Erythromycin or Penicillin x 2 wks
- Post exposure Abx - contact monitor for 7d, nasopharyngeal and throat culture
- Asymptomatic = tx w/ macrolide abx (erythromycine 500 mg PO q6h x 7 or Pencilling G benzathine x1)
- Vaccine
- Myocarditis common complication
EBV
Viral Diseases
Epstein barr mononucleosis, incubates 30-50d, transmission via oropharyngeal secretions and saliva
Sxs
- fever + cervical posterior chain lymphadenopathy + pharyngitis
- maculopapular rash develops in 80% of pts when tx with amox
- RUQ pain 2/2 splenomegaly for splenic rupture
Dx
- Monospot or heterophile antibodies test - EB IgM
- Atypical lymphocytes
Tx
- Supportive tx, abx not helpful
- Splenic rupture
- recover in 1-4 wks
- Rash after given amoxicillin
Erythema Infectiosum
Viral Diseases
Parvovirus B-19
Sxs
- Slapped cheek rash on face,
- circumoral pallor 2-4d lacy reticular rash on extremities
- no prodromal
Dx
- Clinic - enlarged nuclei
- Parvo B19 IgM ab and PCR
Tx
- symptomatic
Genital Herpes Simplex Virus Infection
Congenital Disorders
HSV is ToRCH => neonatal herpes
Sxs
- multiple vesciular lesion on skin, involvement of internal organs or CNS
Tx - antiviral drugs or C section
Hand Foot Mouth Disease
Viral Exanthems
Coxsackie type A virus
Children < 10 yo; very contagious in 1st week - spread via direct contact w/ saliva and mucus
Herpangina Is blister located to just the mouth
Sxs:
- Small, tender, erythematous papules or vesicles on pharynx, mouth, hands, feet
- Punched out, cratered
- Irritability
- Loss of appetite
- General irritability
- Feeling unwell
Dx - clinical
Tx
- clears up in 10 days
- pain meds for sxs relieve
- Good hand hygiene
Helminth
Parasitic Infections
intestinal infections - worm like parasites
Nematode - GI symptoms and cough
- pinworm - anal pruritus morning, scotch tape test
- Ascaris lumbricoide - roundworm - vague abd symp
- tx w/ mebendazole
Cestodes - tapeworm - cause GI symp and wt loss
- tx w/ praziquantel
Trematodes - flukes - Schistoma - swimmers itch
Herpes Zoster
Varicella (chickenpox) - reactivation causing maculopapular rash along one dermatome
Dx - Tzanck Smear - multinucleated giant cells
Zoster Opthalmicus
- shingles w/ CN V - dendritic lesions on slit lamp
Zoster Oticus (Ramsay-Hunt Syndrome)
- facial n CN 7, otalgia
- lesion on ears, auditory canal and TM
- facial palsy auditory symptoms
- ddx Bell’s palsy
Tx:
-
Acyclovir, valacyclovir, famciclovir - given w/in 72 hrs to prevent post-herpetic neuralgia
- Disseminated IV acyclovir
- Post herpetic Neuralgia pain > 3 mos- parethesias or decreased sensation
- Vaccine - Shingrex (not live) > 50yo, 2x shot
- Zostavax - live attenuated virual vaccine
Histoplasmosis
Fungal Disease
Histoplasma capsulatum;
- HIV pts low grade fevers = CD4 < 150
- _bat droppings, bat caves, Mississippi and Ohio River valley_s; inhalation of fungal spores
Sxs
- low grade fevers
- cough
- hepatosplenomegaly
- tongue ulceration
Dx
- Fungal staining
- ele Alkaline phosphatase and LDH
Tx
- Ampho B
- Itraconazole PO - mild to mod dz
- no need for prophy
HIV
AIDS = CD4 < 200 ;suspectible to many opportunistic infx
Sxs
- Acute HIV syndrome: mononucleosis like illness - rash and mucocutaneous ulceration**
Dx
- EIA = 4th gen antigen/antibody combo HIV 1/2 immunoassy - measure HIV antibodies and antigen
-
confirmatory HIV Viral Load
- detect sooner exposure
- ELISA and confirmed by Western blot
Tx
- HAART if CD4 <350 or viral load PCR RNA > 55,0000
- 2NRTIs + NNRTI or PI
- NRTI - Emtricitabine, and Tenofovir
- NNRTI - Efavirenz - can cause CNS disengagement*
- PI - Darunavir
- NRTIs + INSTI
- INSTI - Raltegravir, Dolutegravir
- can cause lipodystrophy + metabolic SEs (lactic acidosis and N/V/D)
- INSTI - Raltegravir, Dolutegravir
HPV
Viral Diseases
DS DNA,
Cervical intraepithelial neoplasia - 16, 18, 21, 33 are cancerous
Condyloma acuminatum - genital warts, 6 & 11 w/ kiocytes
Condyloma lata - 2/2 syphillis
Cutaneous warts - 1, 2, 4
Dx
- Shave or punch biopsy
- Koilocytic squamous epithelia cells in clumps
- HPV DNA on cervical swabs
Tx
- Skin warts - self limited or podofilox or cryotherapy
-
Gardasil quadrivalent vaccine against 6, 11, 16, 18
- M and F 11 to 12 and approved through 9 to 26
Influenza
Viral respiratory infx by orthomyxovirus (three strains A, B, C)
sxs
- fever, coryza, cough, headache, malaise
Dx
- rapid antigen test in clinic
- rapid serology more accurate
- CXR - bilateral diffuse infiltrates
Tx
- symptomatic for most
- antivirals w/in < 48-72 hrs
- Tamiflu/Oseltamivir or Zanamivir/Relenza for influ A & B
- hospitalized pts
- outpt with severe progressive illness
- high complications risk
- IMC
- chronic med conditions
- >65yo
- pregnant or 2 wks pp
Lyme Disease
Borrelia burgdorferi from Ixodes/deer tick
Sxs
- Early localized - 7 to 10d after bite, erythema migrans rash “bullseye”
- Early Disseminated - 1-12 wks after bite
- flu-like syndrome (malaise, fatigue, chills, fever, HA, stiff neck, myalgias, arthralgias)
- Late Disease - persistent synovitis and arthritis, AV block
Dx - ELISA + by 3rd week
Tx - Doxycycline 200 mg x 1d w/in 72 hrs
Malaria
Parasitic Infections
Plasmodium vivax, p. malaria, p. ovale, p. falciparum (most virulent), knowlesi (new)
transmitted by anopheles mosquito
Sxs
- Periodic chills, fever, and sweats (fever every 3 days)
- Splenomegaly > 4d of sxs
- travel hx
Dx
- Giemsa stain peripheral smear
- thick/thin blood microscopy
Tx
- Chloroquine,
- chloroquine resistance - atovaquone-proguanil> mefloquine (night terrors, nightmares)
- Primaquine - P. Vivax but G6PD
MRSA
Bacterial Diseases
Common in diabetics, hospitals, prisons, IVDU, nursing homes = people with open wounds, invasive devices (catheters) and weakened immune systems
Sxs:
- Boil or pimple type lesion = spider type lesion
- “pustule on erythematous base”
- transmission via direct contact
Dx - culture
Tx
- Irrigation and debridement
- Mupirocin 2% = small lesions
- PO Abx for bigger lesion = Bactrim, Doxy, clinda
- IV Abx for severe = Vanco, linezolid,
Mumps
Viral Diseases
Paramyxovirus family; transmitted w/ respiratory droplets
incubats 12-14 d;
Sxs
- parotitis
- orchitis
- aseptic meningitis
- MCC of pancreatitis in children
Dx:
- Clinical, PCR if needed
- amylase ele if +inflammation of salivary gland
Tx:
- supportive; lasts 7-10 days
- Contagious up to 9d after onset
- isolate pt 5 days
- MMR vaccine 12 -15 mos, then 4-6yo
Mycobacterial
Fungal Disease
Mycobacterium avium complex (MAC) - CD4 <50
- fever, diarrhea, wt loss, anemia
- present in soil and water
- dx w/ AFB and culture
- Tx w/ clarithromycin + ethambutol for at least 12 mos
- Prophy w/ azithro or clarithro if CD4<50
Tuberculosis - Mycobacterium tuberculosis
- cough, nt swts, wt loss, IMC
- XRay cavitary lesion, infiltrates ghon complexes
- Acid fast bacilli, caseating granulomas
- Mantoux Skin test - check TB slide in pulm
- tx
Pinworms
Parasitic Infections
Enterobiasis vermicularis
Sxs
- perianal itching at night
- eggs transmitted via food or surfaces
Dx
- scotch tape test - eggs under microscopy
Tx
- Mebendazole or albendazole
Pneumocystis
Fungal Disease
P. jiroveci - transmitted by aerosol route, no disease in IMC pts
CD4< 200
Sxs
- Subactue fever, SOB, non productive cough - exam often not consistent w/ degree of hypoxia
Dx
- CXR - diffuse, bilateral perihilar infiltrates
- gold std - silver stain vs PCR
- ele LDH
Tx
-
Bactrim
- if allergic tx with pentamidine
- add prednisone if PaO2 < 72mmHg
- proph bactrim CD4<200
Rabies
Viral Diseases
CNS infection with RNA Rhabdovirus
transmission via dogs, raccoons, skunks, bats, fox, coyote
Incubate 1-3 mos
Sxs
- Hydrophobia**
- pharyngeal spasms, aerophobia (fear of drafts of fresh air)
- Hyperactivity
Dx
- Negri bodies - eosinophilic inclusion bodies, found in brain of dead bodies
- animals observed for 7-10d
Tx
- Once sxs occur, patients rarely survive
- Post exposure prophy
- HDCV (Rabies vaccine) given day 0, 3, 7, 14 PLUS
- rabies Immune globulin 1/2 injected into wound, 1/2 IM
- If previous exposure or vaccine - rabies vaccine day 0 and 3 w/o immune globulins
Rheumatic Fever
Bacterial Diseases
Inflammatory reaction to GABHS pharyngitis w/ formation of antistreptolysin antibodies (ASO) => reacts with synovium, myocardium, and heart valves
Sxs
- initial sxs 2-4 wks after strep infection
Dx
- GAS culture or ASO, ESR, CRP
- EKG
-
Jones Criteria (2 major criteria, 1 major + 2 minor)
- Major
- J - joint involvementpolyarthritis
- O - myOcarditis
- N - subcut nodules
- Erythema marginatum
- Sydenham Chorea - rapid involuntary movement on face, hands and feet
- Minor
- CRP incr
- Arthralgia
- Fever
- ESR incr
- Prolonged PR invtl on EKG
- Major
Tx
-
pen G benzathine 1.2mil units IM q 3-4 wks
- if < 27kg, 600k unites IM q 3-4wks
Rocky Mountain Spotted Fever
Bacterial Diseases
Rickettsia rickettsii, spread by American dog tick
Sxs
- 2-14 days after tick bite => develop flu like symptoms
- fever, chills, myalgias, headache
- red maculopapular rash on starts wrists and ankles (palms and soles) spread centrally over 2-3 days. face is spared
Dx - Indirect fluorescent antibody (IFA)
Tx -
- doxycycline or
- chloramphenicol 2nd line for preg
Roseola (6th Disease)
Viral Diseases
Caused by HHV 6 and 7; Between 6mos-2yo
Sxs:
- Sudden high fever (102-104)
- Red rash appears as fever subsides
- blanching maculopapular rash - neck/trunk => face => extremities
- rash lasts for 1-2 days
Dx - clinical
Tx - bed rest, fluids, antipyretics
Rubella (German’s Measles)
Rubella virus - spreads through sneezing/coughing
Contagious 1-2 wks before sxs
Teratogenic in 1st Trimester
Sxs:
- Erythematous, discrete maculopapular exanthem
- First on face, spreads to trunk and extremities; generalized w/in 24 hrs
- lasts for 3 days
- Fever
- Lymphadenopathy
Dx -
- EIA
- Serological assays
- Rubella specific IgM abs remain + for > 1 year.
- MMR vaccine - 12-15mos, then 4-6yo
Measles (Rubeola)
Viral Diseases
Paramyxovirus via respiratory droplets
Sxs:
- 10-12 days incubation
- Prodrome
-
1-3 d; 3 C’s
- Cough, Coryza, Conjunctivitis
-
1-3 d; 3 C’s
- Enanthem
- 48 hrs before Exanthem
- Koplik’s spots - red/white/blue spots In mouth
- Exanthem
- 4 days after fever onset
- Morbilliform - maculopapular, blanching rash
- Cephalocaudal - head to extremities spread
Dx: Clinical, Measles IgM abs
Tx:
- supportive, anti-inflammatories, isolate 1 wk after rash onset
- MMR vaccine - 12-15mos, then 4-6yo
Salmonellosis
Bacterial Disease
Typhoid & Enteric fever vs Gastroenteritis; transmitted via fecally contaminated food
Sxs
Enteric/ Typhoid fever - salmonella typhi = flu like bacterial infection
- Constitution sxs, HA, rose spots on abd, constipation or diarrhea, returning traveler
- Tx FQ or ceftriaxone 1g IM or IV q 12h for 14 d
Gastroenteritis
- egg yolk or improperly handled food
- GI symptoms “pea soup diarrhea”, HA
- tx w/ FQ
Dx
- Leukocytosis, low plts
- Stool culture
Sepsis
Systemic Inflammatory Response Syndrome (SIRS) in repsonse to toxins
RF - increased aged, immunosuppressed, prolonged hospitalization
Sxs
- fever, hypotension, incr WBC, change in LOC, Tachycard/pnea
Severe Sepsis
- poor organ function or insufficient blood flow, evident with low blood pressure, high blood lactate, or low UO
Septic Shock
- low BP d/t sepsis that does not improve with IV fluids
Quick SOFA - predict mortality
- new or worsened mentation
- RR >/=22
- Systolic BP = 100 mmHg
Tx
- IV fluids/pressors
- empiric abx, send blood cultures
- remove all existing lines
Shigellosis
Bacterial Disease
Gram neg bacteria; crowded conditions - daycare, transmission via direct person-person or contaminated foods and water
Sxs
- Diarrhea, lower abd cramps, tenesmus
- fever, chills, anorexia, headache, malaise
- Stools loose and mixed with blood, mucus
- Dehydration common
Dx
- HLA-B27
Tx
- Fluid resus
- Abx - Bactrim > Cipro > FQ
Loperamide, or diphenoxylate
Syphilis
Treponema pallidum - 3 phases, 3 weeks incubation
Primary syphilis
- painless chancre in genital or groin region = 3-6 weeks
Secondary syphilis
- erythematous rash on palms and soles
- condyloma lata
Tertiary syphilis (latent)
- major vessel change (aorta), neurosyphilis or gummas
Neurosyphilis - years later
-
Tabes dorsalis - slow degen of nerve fibers
- small nonreactive pupils, sensory ataxia, lancinating pain
Dx - RPR/VDRL confirmed with treponemal antibody-absorption test (FTA-ABS)
Tx
- IM Penicillin G
Tetanus
Bacterial Disease
Clostridium tetani - anaerobic toxin; neurotoxin that interferes with neurotransmission; uncontrolled spasms and exaggerated relfexes; usu from puncture wounds; incubation - 5d to 15 wks
Sxs
- pain and tingling at inoculation site - spasticity of muscles nearby
- Jaw and neck stiffness, dysphagia, irritability
- Hyperreflexia & muscle spasms (trimus) develop
- Painful tonic convulsions, glottis spasms, respiratory muslces, asphyxia
Dx
- Culture but can have false negative
Tx
- post exposure prophy - Vaccination Td, Tdap
- Hyperimmune human globulin (TIG) neutralizes toxin
- Metronidazole or penicillin = high mortality
- spasmolytic drug - diazepam
Toxoplasmosis
Toxoplasma gondii - parasitic protozoan
pregnant female exposure to cat feces
Sxs:
- encephalitis + chorioretinitis + intracranial calc in AIDS pts CD4 <100
Dx
- ring enhancing lesion
- toxo IgG and IgM
- part of ToRCH syndrome
Tx
- Prophy CD4 < 100 with bactrim
Trichomoniasis
Parasitic Infections
Sexually active women
foul smelling, greenish dc
Vaginal pH > 4.5
strawberry cervix
motile flagellated protozoa
Tx metronidazole 2g PO x 1
Zika Virus
Congenital Disorders
SS RNA transmitted through Aedes mosquito; screen pregnant women 1st and 2nd trimester
Sxs
- Macular pruritic rash
- arthralgia, conjunctivitis, low grade fever, and miscarriage
- Fetus w/ microcephaly, Intracranial calcifications, cerebral malformation
Dx
- Serum or urine Zika virus IgM w/ real time PCR for confirmatory
Tx
- self limited, conservative and supportive care
- avoid aspirin and NSAID
Coccidioides
Fungal
Western US
Non-remitting cough, not responding to usu treatment
Dx - EIA for IgM and IgG
Tx - fluconazole and itraconazole
