infectious stuff Flashcards
HIV and Aids Related Infections
Ophthalmologic illnesses
*CMV Retinitis
- Blurry or worsening vision
- Eye pain
- Treat with ganciclovir
HIV and Aids Related Infections
GI/Diarrheal illnesses
- Cryptosporidium
- Isospora
- Oral/Esophageal candida
HIV and Aids Related Infections
Neurologic illnesses
- Cryptococcus
- Headaches
- AMS
- High opening pressure on LP
- Diagnosed with India Ink or Ag titer
- Treat with Amphotericin B +/- Flucytosine
- Toxoplasmosis
- More focal neuro symptoms
- CT with “ring enhancing lesions”
- Treat with Pyrimethamine + Sulfadiazine + Folinic Acid
HIV and Aids Related Infections
Pulmonary illnesses
-Not always PCP!
-Most common sources for pneumonia are still the common bugs (Strep pneumo and H. flu)
- With AIDS also consider:
— TB
—Pneumocystis pneumonia
———-Bilateral “ground-glass” opacities on CXR
High LDH on labs
———-Treat with TMP-SMX
———-Add steroids if very unwell
HIV and Aids Related Infections
Oncologic illnesses
*Kaposi Sarcoma
- Most common cancer in AIDS patients
- Subcutaneous, red/brown or red/blue nodules on face and extremities
- Can also occur within GI tract
- Call Oncology
Many adverse drug reactions related to HIV/AIDS therapy including
- Didanosine → pancreatitis
- Indinavir → kidney stones
- Efavirenz → psychosis
- Pentamide → hypo/hyperglycemia
Bacterial food poisoning
Reheated fried rice
what kind of bug?
Bacillus cereus
Bacterial food poisoning
Traveler’s diarrhea
what kind of bug?
E. coli
Bacterial food poisoning
Contaminated meat and poultry
what kind of bug?
Clostridium perfringens
Bacterial food poisoning
- Contaminated water or shellfish
- Watery diarrhea
- Dehydration
- Metabolic acidosis
- Rehydration therapy
what kind of bug?
Vibrio cholera
Bacterial food poisoning
- Tuna, mackerel, and mahi-mahi
- Histamine release
- Metallic or peppery taste
what kind of bug?
Scombroid
Bacterial food poisoning
- Snapper, barracuda and grouper
- Paresthesias
- Reversal of hot/cold perception
what kind of bug?
Ciguatera
- Potentially fatal neuroparalytic syndrome caused by Clostridium botulinum
- Descending motor neuron process, no sensory component
- Neurotoxin acts at motor end plate → weakness → affects diaphragm → causes respiratory failure
Botulism
_________ is spread by:
- Foodborne
- Improper canning techniques
- Honey ingestion before age of 1
*IV drug users contract it in wounds
- Spectrum of disease in infants
- Constipation → Poor feeding → Weak cry → Floppy baby
Botulism
Botulism treatment
- Treatment based on clinical presentation- don’t wait for test results
- Treat with immunoglobulin
Febrile Traveler
Africa
- African Sleeping Sickness
- Spread by tsetse fly
- Present with lethargy, sometimes psychosis
- Treat with pentamidine or suramin
- Ebola
- Spread via direct contact with blood or bodily fluids/tissues of infected animals/people
- Supportive treatment
Febrile Traveler
Central or South America
*Chagas Disease
- Reduviid “kissing” bug
- Edema, cardiac and GI problems
- Treat with anti-trypanosomals (benznidazole or nifurtimox)
Febrile Traveler
Southeast Asia and Australia
*Leptospirosis
- Animal vectors, contaminated soil, water
- Severe forms of illness cause pulmonary hemorrhage
- Treat with doxycycline or ceftriaxone
Febrile Traveler
Tropics in general
*Dengue
- Aedes mosquito
- Fever, rash, and joint pain
- Supportive treatment
African Sleeping Sickness
treatment:
Treat with pentamidine or suramin
Ebola
treatment:
Supportive treatment
Chagas Disease
treatment:
Treat with anti-trypanosomals (benznidazole or nifurtimox)
Leptospirosis
treatment:
Treat with doxycycline or ceftriaxone
Dengue
Supportive treatment
what kind of fungal infection?
- Rhizopus fungus, aggressive infections
- Nasopharynx of immunocompromised patients
- Prompt surgical debridement
Mucormycosis
what kind of fungal infection?
- Pulmonary disease most common
- Increased risk if have asthma or COPD
- Cavitary lesions
- Consider chronic form in patients whose respiratory symptoms do not respond to prolonged antibiotic therapy
Aspergillosis
Mucormycosis
Treatment:
Prompt surgical debridement
what kind of fungal infection?
- Southwest USA, aerosolized spores from soil
- Pulmonary disease
- Synovitis
- Hepatosplenomegaly
- Meningitis leading to hydrocephalus
- Treat with “azoles”, amphotericin B if disseminated
Coccidioidomycosis
Coccidioidomycosis
Treatment:
Treat with “azoles”, amphotericin B if disseminated
what kind of fungal infection?
- Ohio, Missouri and Mississippi River Valleys, bird droppings in damp soil
- Pulmonary disease to disseminated disease
- Disseminated form includes GI, cardiac, ocular and CNS effects
- Treat with “azoles”
Histoplasmosis
Histoplasmosis
Treatment:
Treat with “azoles”
what kind of fungal infection?
- Great Lakes region, inhalation of spores
- Pulmonary disease
- Skin lesions- sharply demarcated, grey to violet verrucal lesions, irregular borders
- Lytic bony lesions
- Prostatitis
- Treat with “azoles”
Blastomycosis
Blastomycosis
Treatment:
Treat with “azoles”
what kind of gangrene?
- “Mummified” appearance
- Poor vascular supply
- Not infected
- Toes/fingers often auto-amputate
- Well-demarcated regions
Dry gangrene
what kind of gangrene?
- Bacterial infection
- Poor blood supply
- Malodorous
- Erythema
- Drainage
- Ulceration
- Aggressive antibiotic therapy
- Can cause sepsis
Wet gangrene
what kind of gangrene?
- Gas forming bacterial infection (Clostridium, Strep, Vibrio)
- Necrotizing soft tissue infection
- Crepitus on palpation
- Gas on X-ray
- Aggressive resuscitation and early surgical debridement
- Immunocompromised patients are at high risk
Gas gangrene
- South West USA, spread via aerosolized mouse urine
- Non-specific viral prodrome → respiratory failure/ ARDS/cardiovascular collapse
- Supportive treatment
Hantavirus
- Sudden onset high fever, myalgias, sore throat
- Pediatric population often present with GI symptoms
- Risk of primary influenza pneumonia or secondary bacterial pneumonia
- Treat with antivirals for high risk groups
Influenza
- Water-borne (plumbing, sprinklers) intra-cellular bacteria
- Does not spread person-to-person
- Usually pneumonia PLUS one or more of the following
- GI symptoms
- Hyponatremia
- Proteinuria
- Hematuria)
- CXR may look atypical
- Confirmatory test is urine legionella Ag
- Treatment is azithromycin/quinolone
Legionella
Legionella
treatment:
Treatment is azithromycin/quinolone
- Spirochete Borrelia that uses deer tick as host
- Tick must be attached approx. 72 hrs. or longer to transmit disease
- Lyme disease progresses in stages (days-months-years)
- Classic case description:
- Pennsylvania hiker (Northeast USA)
- Erythema migrans (target lesions) spreading out from bite within days
- Bell’s palsy (bilateral in particular)
- AV block within months
- Treat with doxycycline, or ceftriaxone for the ixodes tick
- No doxycycline if under age 8 or if pregnant
- Jarisch-Herxheimer reaction
- Spirochete deaths → SIRS-like response (usually syphilis, but so see in Lyme)
Lyme Disease
Lyme Disease
treatment :
*Treat with doxycycline, or ceftriaxone for the ixodes tick
Malaria
Test
Thick and thin peripheral blood smear
Malaria
Treatment
- Depends on type of malaria and where contracted
* Antimalarials (quinidine, artemisinins) and/or antibiotics such as doxycycline or clindamycin
- Animal reservoirs
- Raccoons
- skunks
- foxes
- bats
- coyotes
- Spread via bites/scratches from these animals
- If bat found in house, residents should be treated for rabies (bats = high risk reservoir)
*Bite/scratch injects virus into muscle from where it travels into CNS
- Presentation
- Viral prodrome → Furious stage (agitation) → “Dumb” stage (incoordination, paralysis) → Death
Rabies
Rabies
treatment:
- Inject as much rabies IG as possible directly into bite (depends on bite size and location)
- Inject remaining amount via IM route in thigh
- Initiate rabies vaccine series
- Toxoplasma gondii from cat feces
- If immunocompetent might have flu-like illness, not usually severe presentation
- Immunocompromised patients at higher risk of more serious illness, including
- CNS infections
- Retinitis
- Myelopathy
- Primary infection during pregnancy can cause severe congenital infections
- Ring enhancing lesions on head CT/MRI
- See IgM (early) and IgG (late)
Toxoplasmosis
Toxoplasmosis
Treatment:
Treat with pyrimethamine or TMP-SMX
*Mosquito-borne
- Clinical features
- Usually flu-like illness
- 1% develop meningoencephalitis
- Labs
- CSF pleocytosis
- Send for West Nile Ab
- CSF negative gram stain
- CSF high protein count
West Nile Virus
West Nile Virus
treatment:
- Start treating immediately, don’t wait for cultures
- Antibiotics and steroids
- Antivirals
what kind of worm?
- Perianal itching, worse at night
- “Scratch then ingest” cycle
- Scotch tape tes
Pinworm
what kind of worm?
- GI infection → bloodstream → lungs → GI tract
- Can cause eosinophilia
Roundworms (common roundworm, hookworm, strongyloides)
what kind of worm?
- Elephantiasis
- River blindness
- Pulmonary problems
Flukes from soil and stool cause
what kind of worm?
- Pork variant → cysts in muscles and brain → seizures
- Fish variant → B12 deficiency
Tapeworms from raw pork/beef/fish
Worms
tx:
Albendazole and mebendazole for most; ivermectin for river blindness
*Hospital-acquired Device infections Indwelling lines
- Community-acquired “Spider bite”o PVL gene association in the bacteria itself People living in close quarters
- Members of sports teams
- I&D if abscess
- Clindamycin, TMP-SMX, or vancomycin
- If recurrent infections, consider decolonization protocol (mupirocin in nose and skin cleaning for one week)
MRSA
MRSA
tx:
Clindamycin, TMP-SMX, or vancomycin
*Group A Strep, Staph aureus or polymicrobial most common
- Clinical Features:
- Erythema with poorly defined regions
- Edema extends beyond regions of erythema
- Hemorrhagic bullae
- “Dishwater fluid”
- Crepitus
- Pain out of proportion
- Hyponatremia
- Leukocytosis
- Lactic acidosis
- High CRP
- Gas in soft tissues on X-ray or CT
- May exhibit “la belle indifference” where they are clearly severely ill but don’t seem to care
- Requires early and aggressive surgical debridement
- Clindamycin or broad-spectrum antibiotics
Necrotizing Fasciitis
- Usually secondary to Candida albicans
- Newborns and immunocompromised patients are more susceptible
- White/gray plaques in mouth/throat that can be scraped off
- Swab shows yeast and micro-hyphae
- Treatment
- Nystatin swish and swallow QID
- If treating breastfeeding newborn treat the mother’s breasts as well
Oral Candidiasis (Thrush)
Oral Candidiasis (Thrush)
treatment:
- Nystatin swish and swallow QID
* If treating breastfeeding newborn treat the mother’s breasts as well
*Bordetella pertussis, highly contagious acute respiratory infection
- Different phases of Bordetella pertussis
- Catarrhal (URI) → Paroxysmal (cough and whoop) → Convalescent (weeks to months)
- Serious complications
- Secondary bacterial/viral pneumonias or other infection
- Neonates can present with apneic, seizures/encephalitis/ICH
- Supportive treatment unless secondary bacterial pneumonia, then antibiotics
- Admit neonates
- Macrolides to shorten illness and for post-exposure prophylaxis
- Vaccinations and involve public health
Pertussis
- SIRS criteria = at least 2 of the following:
- Temp >38º (100.4º) or <36º (96.8º)
- RR >20 bpm (or PaCO2 <32)
- HR >90 bpm
- WBC >12,000 OR <4,000 OR >10% bands
- Sepsis = SIRS + confirmed Infection
- Severe Sepsis = Sepsis + 1 or more signs of organ dysfunction
- Septic Shock = Severe Sepsis + hypotension refractory to fluids
Sepsis & Bacteremia
Sepsis & Bacteremia
treatment:
- Fluids
- Antibiotics
- Pressors
Sepsis & Bacteremia
Treatment Goals
- MAP >65
- Urine output >0.5-1cc/kg/hr
- Central venous pressure >8mm Hg
- Central venous O2 sat >70%
- Decreasing serum lactate levels
- Haemophilus ducreyi (gram negative rod)
- Highly infectious genital ulcerative disease
- Increases risk of HIV transmission (as do all ulcerative STIs)
- Don’t confuse with HSV
- Chancroid ulcerations and inguinal lymphadenitis
- Ulcers and bubos usually present at same time
Chancroid
Chancroid
Treatment
Options include azithromycin, ceftriaxone, ciprofloxacin or erythromycin
*Wide range of clinical presentations (e.g. discharge, cervicitis, pelvic pain, dysuria)
- Fitz-Hugh-Curtis syndrome
- Ascending PID infection, presents with RUQ pain
- “Violin string” adhesions around liver capsule
*NAAT test (urine or vaginal swab)
Chlamydia
Chlamydia
Treatment
Azithromycin or doxycycline
*Common co-infection with chlamydia
- Common sites of infection
- Oral
- Pharyngeal
- Conjunctival
- Anorectal
- Cervical
- Urethral
- Disseminated Gonococcal Infection (DGI) has two common presentations (that may overlap)
- Arthritis-dermatitis syndrome
- Purulent arthritis without skin findings
- May not have mucosal symptoms at time of presentation with DGI
- Tenosynovitis and skin lesions are common in DGI but rare in other forms of infectious arthritis
Gonorrhea
Gonorrhea
Treatment:
- Ceftriaxone IM PLUS azithromycin or doxycycline (for likely co-infection with Chlamydia)
- Longer course of treatment for DGI
- DGI may need repeated surgical wash-outs
- HSV-1 and HSV-2
- Common viral syndrome in children
- Clinically see:
- Grouped vesicles, sometimes painful or tingling rash
- Viral prodrome
- Classic anatomical presentations:
- Gingivostomatitis/pharyngitis-Oral infections
- Herpetic whitlow-Infections on fingers (do not I+D these!)
- Herpetic keratitis-Periorbital infections (Ophtho consult!)
- Herpetic gladiatorum-Lesions on head, neck or trunk (think wrestlers)
- Neonatal HSV-After transmission from active maternal infection during delivery
- Eczema herpeticum-With supra-infection of eczematous lesions (potentially fatal!)
- Urogenital outbreak
- Can cause urinary retention (always check the genital region!)
Herpes Simplex
Herpes Simplex
Labs
Tzanck smear
Herpes Simplex
Treatment
Acyclovir or other antivirals
*Bacteria usually Staph or Strep
- Contracted from:
- Prolonged use of tampons
- Nasal packing
- Burns
- Surgical sites
- Secondary infection
*Classic sign is erythroderma
- If Staph
- Diffuse rash with erythroderma/desquamation
- Mucosal hyperemia
- Septic shock
- Rule out necrotizing soft tissue infection
- High mortality
Toxic Shock Syndrome
Toxic Shock Syndrome
Treatment:
- Aggressive resuscitation
- Fluids
- Antibiotics
- Unilateral dermatomal rash - “dew drops on a rose petal”
- Patients may get neuropathic pain preceding rash
- Post-herpetic neuralgia can occur and can be hard to control
- Treat with antivirals if rash has been present for < 72 hours of rash
- Hutchinson sign
- If see lesions on tip of nose, look for dendritic pattern on cornea
- If corneal lesions, consult Ophthalmology urgently
Varicella Zoster
- 8th cranial nerve
* Ipsilateral facial paralysis, ear canal/pinna lesions, ear pain and vertigo
Ramsay Hunt Syndrome
Ramsay Hunt Syndrome
Treatment
- Antivirals
- Steroids
- Pain meds
