ID Flashcards
Factors that increase risk for fungal infection
- immunity
- Recent of current use of antifungal medication
- Risk of exposure
- Neutropenia (Invasive candidiasis and aspergillosis)
List oppurtunistic
fungal infections
virus
Parasite
Fungus
- Cryptococcus
- Histoplasma
- Candida
- Pneumocystis
Virus - Cytomegalovirus
Parasite - Toxoplasma
pathogen responsible for Criptococcus
C. neoformans and C. gattii
transmission of Criptococcus
Transmission via air droplets and bird dropping
Spores are inhaled, lodge into the lung alveoli then disseminate hematogenously and cause infection
Si/Sx of Criptococcus
what is most common??
The most common is meningitis
- Malaise (76%)
- Headache (73%)
- Fever (65%)
- N/V(42%)
- Cough/ SOB (31%)
- Altered MS (28%)
- Temperature above 38.4 (56%)
- Papilledema (33%)
- Meningeal signs (27%)
Dx & Tx of Criptococcus
Dx: cryptococcal antigen in CSF
Tx:
- Amphotericin B (80%)
- Fluconazole (50%).
Tranmission of Histoplasmosis
inhalation & Exposure to chicken coop
si/sx of Histoplasmosis
Fever
weight loss
skin ulcers
Hepato-splenomegaly
lymphadenopathy
Dx & Tx of Histoplasmosis
Dx: Urine: H. capsulatum antigen sensitivity 95%
Tx:
- Amphotericin B an/or
- Itraconazole total 12 weeks
the strain causing the disease is from the patient’s own GI flora
Candidiasis
2 types of canidiasis
CD4 counts?
Oropharyngeal candidiasis (OPC) - CD4 <300.
Esophagitis - CD4 <100.
types of Oropharyngeal candidiasis (OPC)
- Erythematous
- Hyperplastic
- Angular Cheilitis
- Pseudomembranous
tx of Candidiasis
avoid??
Itraconazole (97%) or Fluconazole (87%)
Avoid topical treatments (nystatin)
- Lower cure rates
- Higher relapses rates
the most common cause of dysphagia and odynophagia in AIDS.
Esophageal candidiasis
Dx & Tx of Esophageal candidiasis
Dx: EGD
Tx: Fluconazole - If unable to swallow use IV
pathophys of Pneumocystis Jirovecii
unique tropism for the lung and rarely invading the host.
•By attaching to the alveolar epithelium cause inflammation, interstitial edema and diffuse alveolar damage
si/sx of Pneumocystis Jirovecii
Gradual onset and progression of
- Fever
- dry cough
- dyspnea.
Average 1 month before medical consultation
Dx of Pneumocystis Jirovecii
best imaging & best lab??
Best imaging test: HRCT chest.
- If normal no PCP
Best lab test: BAL+ immunofluorescence
tx of Pneumocystis Jirovecii
TMT-SMX
Adjunctive steroids if PO2 <70
most important form of Cytomegalovirus
CMV can affect mainly retina ( the most important form of CMV), CNS and GI tract. Rare in lung.
CMV retinitis
si/sx of CMV retinitis
- No pain but floaters, blurry vision, decreased peripheral vision
- Light flashes or sudden vision loss can occur
- Usually start in one eye but often involves both eyes
- Blindness due to retina detachment 2-6 months if untreated
Dx & Tx of CMV retinitis
Dx: Perivascular fluffy yellow-white retinal infiltrate +/- hemorrhage
Tx: IV Ganciclovir , lifelong
pathogen for Toxoplasmosis
30% of people in USA are seropositive (IgG) for T. gondii.
The annual risk of of developing Toxoplasmosis encephalitis among patients with a
- CD4<100 and positive serology is ___%
- ___% if CD4<50 if they do not receive prophylaxis
The annual risk of of developing Toxoplasmosis encephalitis among patients with a
- CD4<100 and positive serology is 30%
- 75% if CD4<50 if they do not receive prophylaxis
Si/sx of toxoplasmosis
HA
Confusion
Fever
Lethargy
Seizure
Focal Sign
AMS
Psychomotor Retardation
Menignismus
Dx toxoplasmosis
Best imaging: MRI brain
Bc CNS lymphoma may look similar then:
- Obtain IgG serology for T. gondii
- Order MRI brain and look for more than 1 lesion
- If LP was done then order cytology for malignant cells and EBV PCR
- Where available order PCR for T. gondii
Tx toxoplasmosis
Pyrimethamine+ Sulfadiazine + Leucovorin
Brain biopsy - if no clinical or radiological improvement after 14 days of anti-Toxoplasma therapy.
Most common tick-borne illness in the US & Europe
Lyme Dz
pathogen responsible for lyme
US
Europe & Asia
Borrelia burgdorferi in the US
Borrelia afzelii and Borrelia garinii in Europe and Asia
Si/Sx of Lyme
Early Localized Disease
Early Disseminated Disease
Late Lyme Disease
Post Lyme Syndrome
Early Localized Disease-7-14 days after bite
- Erythema migrans (EM) – bullseye rash
Early Disseminated Disease
- Neurologic – meningitis, facial nerve palsies, radiculopathy (TRIAD)
- Carditis – heart block
- Ocular manifestation
Late Lyme Disease
- Arthritis - knee
- Neurologic fts Lyme encephalopathy – subtle cognitive disturbances & polyneuropathy
- Fibromyalgia
Post Lyme Syndrome
nonspecific symptoms that may persist for month after treatment of Lyme Disease
- Headache
- Fatigue
- Arthralgia
- Cognitive difficulties
- Musculoskeletal pain
Dx Lyme
Spirochetemia on blood culture
ELISA (Enzyme linked immunosorbent assay)
- Most common initial serologic test
- Available for IgM (early), IgG (late), and combined IgM and IgG antibody detection
- If + or indeterminate –> send for western blot
Western Blot Test
- Provides more information regarding which agent of B. burgdorferi are reacting to the serum antibody
Tx of lyme
Doxycycline
Later in dz –> IV abx
Alt: amoxicillin or ceftriaxone
Criteria for Lyme prophylaxis (ALL):
- Attached tick identified as adult or nymph I. scapularis and attached for >36 hours
- Prophylaxis can be started within 72 hours of the time the tick was removed
- Ecologic information indicated local rate of infection of ticks is ≥ 20%
- Doxycycline is not contraindicated
Babesiosis pathogen & transmsission
Ixodes scapularis ticks – typically in nymph stage, size of a poppy seed
During nymph stage the tick searching for a blood meal, B.microti
si/sx of babeosis
Babesia can infect and destroy RBCs -> hemolytic anemia
Jaundice, dark urine
Rash is UNCOMMON
Life threatening to asplenic patients
Dx of babeosis
peripheral blood smear
- On smear may look like Malaria – look for the tetrads and extra cellular mezozites.
- no hemozoin pigments.
Tx of babeosis
Atovaquone + Azithromycin;
OR
Clindamycin + Quinine
Educate the patient to not donate blood products
transmission of Ehrlichiosis
Lone star tick
Blacklegged tick
Blood transfusions
si/sx of Ehrlichiosis
- Malaise, rigors, nausea, high fevers and headache
- Rash – infrequent!!!, if present consider other tick-borne co-infections
- Immunocompromised patients can have severe presentations
dx & Tx of Ehrlichiosis
Dx:
Peripheral Smear – see the bacteria in leukocytes
(PCR)– identify specific genes unique anaplasmosis – most sensitive in the 1st week of illness
(IFA_)_ – not commonly used, measures the antibody to the bacteria. Can take 3 weeks for results
Tx: Doxycycline
- Rifampin for pregnant & families
Dx differentiation b/w
Ehrlichiosis
Anaplasmosis
Ehrlichiosis: Peripheral Smear – see the bacteria in leukocytes
Anaplasmosis: Peripheral Smear – see bacteria in monocytes
Males >40 years in age
Weakened immune system
Residence or time spent in tick habitats, contact with the white tail deer and white-footed mouse
Anaplasmosis
Spread from the bite of an infected tick
Rare cases can be spread thru blood transfusions
si/sx of anaplasmosis
early
late
Bites are usually PAINLESS
People don’t remember being BITTEN
Early Illness (1-5 days)
- Fevers, chills, Severe headache, myalgia, N/V, diarrhea, anorexia
Late Illness
- Respiratory failure
- Bleeding problems
- Organ Failure , Death (RARE <1%)
Dx & Tx of anaplasmosis
Dx:
Peripheral Smear – see the bacteria in the monocytes
(PCR)– identify specific genes unique anaplasmosis – most sensitive in the 1st week of illness
(IFA) – not commonly used, measures the antibody to the bacteria. Can take 3 weeks for results
Tx: Doxycyline
tick borne illness that:
Loves endothelial cells –> inc permeability –> leaky blood vessles
Rocky Mountain Spotted Fever
Si/Sx of Rocky Mountain Spotted Fever
SICK FAST!!! 4-10 days after bite
*Blanching erythematous rash with macules (3rd-5th day of illness)
“Spotless” RMSF may be severe and have fatal outcomes
- Rash initially involves wrists and ankles, spreading centrally to arms, legs and trunk. Involves palms and soles!
- Facial flushing, conjunctival injection and hard palate lesions may occur
Dx of rocky mtn spotted fever
CXR = interstitial infiltrates on chest x-ray, consistent with early pulmonary edema
Echo - minimal myocardial dysfunction
(IFA) assay for IgG R. Rickettsii antigen
- Frequently negative in first few weeks of illness. IgM only available thru some labs and not as specific
Positive PCR helpful but does not rule out if negative as may not have large amounts of DNA in blood because invasive of endothelial.
Tx of rocky mtn spotted fever
Doxycycline
Chloramphenicol – safe in preg up to 3rd tri
Continue abx for 3 days after patient becomes afebrile
Complications of rocky mtn spotted fever
- Encephalitis
- Noncardiogenic pulmonary edema
- Adult respiratory distress syndrome
- Cardiac arrhythmias
- Coagulopathy
- Gastrointestinal bleeding
- Skin necrosis
si/sx of rabies
Encephalitic
Paralytic
Encephalitic (furious) rabies (80%) –
- Hydrophobia & Aerophobia (fear of breathing)
- Hyperactivity of muscle subsiding to paralysis
- “goose flesh”
Paralytic (dumb) rabies (<20%) –
- hypo reflexive
- CN palsy
- ascending paralysis
dx of rabies
_Rabies serum antibody tite_r – will not be positive until later in course
Spinal tap – elevated protein, normal glucose, anti-rabies antibiodies
Skin biopsy –> Saliva
CT head = Cerebral edema
Tx of rabies
Pre-exposure Vaccination: 3 IM injections given at days 0, 7 , and 21 or 28
Post-exposure Vaccination:
- Immunocompetent: 4 IM
- Immunocompromised: 5 IM
NEED vaccine on day 0
*Anopheles mosquito→P. falciparum & P. vivax
transmitted from a female Anopheles gambiae mosquito
- P. falciparum most commonly transmitted disease
- 2nd is P. vivax
Malaria
sporozoites goes to the liver within 1 to 2 hours and can remain dormant for years asymptomatic for 12 - 35 days –> invade RBCs
Malaria
Si/sx of malaria
mild
severe
Mild: Cycle of cold, hot, sweating occurring Every 2 days or every 3 days (cyclical fever!!)
Severe Clinical Presentation
- “cerebral malaria” – confusion, obtunded, seizures, coma
- Hemolysis, hemoglobinuria
- ARDS – inflammation in lungs which impairs O2 exchange
dx malaria
Rapid diagnostic test (RDT) : if + →blood smear
- Evidence of hemozoin – breakdown products of the red cells seen in digestive tracts of the parasites
Smear for speciation & degree of parasitemia
If negative at first, continue testing each day for 2 more days
tx of malaria
Chloroquine
Malarone (atovaquone + proguanil) - NIGHTMARES
Coartem (arthemether + lomefantone)
Mefloquone
Quinine + Doxycycline, Clindamycin or Tertacycline
Most severe encephalitis in America
EEE
Dead-end hosts are HUMANS, EQUINE, SWINE, PHEASANTS
partho of EEE
After a bite, EEE virus is inoculated in dermal tissue, it stats affecting dendritic and Langerhans cell which migrate to Lymphoid tissues. There is replicated
si/sx of EEE
“Encephalitis”
dx of EEE
CBC – leukocytosis (lymphocyte predominant)
ELISA and IFA
Radiologic findings:
- Brain MRI T2 weighted images can report f_ocal lesions in basal ganglia, thalamus and cortex._
Pro Tip: early involvement of the thalamus and basal ganglia can help differentiate between Herpes simplex and EEE
tx of EEE
No antiviral drug has proven beneficial
Supportive care
Steroids worse outcomes!!-avoid
pathophys of west nile
Enters through dermal layer and replicates in dermal dendritic cells and keratinocytes. Then there is visceral-organ dissemination phase followed by third phase which it spreads to CNS
Unclear how it enters the CNS.
cayse of west nile
Culex species of mosquito most common
West Nile can infect birds, dogs and other mammals
Humans are “Dead-end” hosts
si/sx of west nile
50% maculopapular rash on trunk
Virus incubation 2-14 days
Fever – typically 5 days, headache 10 days, fatigue – 1 month
Patients with features of encephalitis progress rapidly.
Neuro changes, muscular weakness, seizures, flaccid paralysis
Dx & Tx of west nile
Dx:
CBC – leukocytosis
Serological detection in blood and CSF – IgM antibody
If high suspicion and initial negative, repeat in 10 days
May see hyponatremia when CNS is involved
Lumbar Puncture: CSF shows elevated protein, + leukocytes, normal glucose levels.
Tx:
Supportive care – will recover
As they recover, may need PT and OT as loss of gross and fine motor skills.
pathogen responisble for tularemia
Francisella tularensis – infected animals
Inhale, touch, rub eye
si/sx of tularemia
RAPID ONSET
Late presentation specific manifestations:
Ulceroglandular tularemia – skin lesion with adenopathy
Glandular tularemia – tender regional lymphadenopathy
Oculogladular tularemia – infection involving the eye
Pharyngeal tularemia – infection involving mouth or throat
Pneumonic tularemia – pulmonary involvement
Typhoid tularemia – systemic illness
dx of tularemia
F. tularensis serology – initial presentation and 2-4 weeks after
Culture and gram-stain – rarely positive
tx of tularemia
mild
severe
severe complications
Mild illness:
- Doxycycline
- Ciprofloxacin
Severe illness:
- Streptomycin
- Gentamicin
Severe complications : Meningitis & Endocarditis
si/sx of plague
Bubonic plaque (80-95%)
Septicemic Plague
Pneumonic plague
Bubonic plaque (80-95%)
- Skin lesions: eschars, pustules, necrotic lesions
- Purpura with associated intravascular coagulation
- Intense pain and swelling LNs (bubo)
- If untreated this can progress to disseminated infection (sepsis), meningitis, or secondary pneumonic plague
Septicemic Plague (10-20%) - Extremely ill
- Fever
- GI symptoms (N/V/D) & Abdominal pain
Pneumonic plague – Sudden dyspnea
- High fever
- Pleuritic chest pain
- Cough +/- blood sputum
- Rapidly fatal unless appropriate treatment is started within the first day
dx plague
Chest x-ray -
- Bronchopneumonia
- Consolidation
- Cavities
- Pleural effusions
Culture and staining
Blood serology
Rapid test
Tx of plague
Drug of choice: Streptomycin IM
- Alt: Doxycycline or Tetracycline
ISOLATION
3 important diagnostic clues of plague
- Presence of fever in a person with known contact with dead rodents or travel to plague-endemic region
- Presence of fever, hypotension, and unexplained regional lymphadenitis
- Presence of clinical findings of pneumonia in association with hemoptysis and sputum containing gram negative rods
•Intense pain and swelling LNs makes you think??
Bubonic plaque
Erythema migrans (EM) – bullseye rash
dx?
Lyme
hemolytic anemia, Jaundice, dark urine
dx?
Babesiosis
Blanching erythematous rash with macules
Rash initially involves wrists and ankles, spreading centrally to arms, legs and trunk. Involves palms and soles
dx?
Rocky Mountain Spotted Fever
Hydrophobia & Aerophobia & “goose flesh”
Dx
Encephalitic rabies
Encephalitic rabies has (hypo/hyper) reflexia
Paralytic rabies has (hypo/hyper) reflexia
Encephalitic rabies has HYPERreflexia
Paralytic rabies has HYPOreflexia
Cycle of cold, hot, sweating – cyclical fever!!
Dx
severe prrsentaion?
malaria
Severe Clinical Presentation: “cerebral malaria” – confusion, obtunded, seizures, coma
50% maculopapular rash on trunk
dx?
West Nile
Main HIV risk for males vs frmales
MSM main risk for males
heterosexual transmission for females
HIV Transmission Risk Fx:
↑Viral load
Lack of circumcision
STDs
Sexual partner number, practices
(Genetic)
HIV Risk Factor Estimator
↑ risk with:
↓ risk with:
↑ risk with:
- Anal sex
- STD (either partner)
- Acute HIV
↓ risk with:
- Condom use
- Pre-exposure prophylaxis
- ART plus undetected viral load
- (Not on the estimator) Circumcision
Dx HIV
Antibody/p24 antigen screen; (+) proceed per algorithm
Viral load as baseline
CD4 count
Ag/HIV1,2 Ab) – look for HIV antibody
- (-) and suspect very recent infection, repeat in a few days
- or jump to RNA viral load
(+), check:
- HIV1,2 Ab differentiation assay
- HIV1 viral load (RNA)
Si/Sx of HIV infection
Early
Latency
AIDS
Early Infection – Shortly after acquisition.
- HIGH VL
- Highly contagious.
- CD4 dips (CD4 about 500) – still protect from opportunistic infections
Clinical latency – No or subtle symptoms.
- VL drops.
- CD4 usually partially recovers.
AIDS: HIV Infection + either
- CD4 <200 regardless of symptoms, OR
- AIDS-defining condition (at any CD4 count)
who to test for HIV??
One-time: Anyone age 13-75
In all pregnancies
With ongoing risk factors (test yearly or more often)
With si/sx acute or chronic infection
Note that 1 of ___ infected persons (~14%) in US unaware! Have low threshold to test.
Note that 1 of 7 infected persons (~14%) in US unaware! Have low threshold to test.
tx of HIV
GENOME STUDY FIRST!!
Recommended starting regimes: use at least 3 drugs.
4 regimens recommended “for most people”
- INSTI (integrase inhib) + two nukes
One regimen with INSTI + 1 nuke but only if
- RNA <500k
- no nuke resistance
- no hep B coinfection.
Early Complications of HIV (CD4 >_____)
Early Complications of HIV (CD4 >200)
- Oral or vaginal candidiasis
- Oral hairy leukoplakia (EBV)
- Herpes Zoster (VZV)
- Seborrheic dermatitis
- Recurrent or atypical HSV
- Kaposi’s sarcoma (HHV-8)
- Extensive, recurrent condyloma (HPV)
Late Complications of HIV (CD4
Late Complications (CD4 <200)
- Pneumocystis jiroveci (carinii) infection
- Cryptococcus neoformans infection
- Toxoplasma gondii infection (reactivation)
- Cytomegalovirus reactivation
- Aspergillus infection
- Mycobacterium avium infection (and other NTMs)
- Cryptosporidiosis
- Lymphomas
- Wasting disease
How does HIV present differently in Elderly??
Tend to have lower CD4 counts at presentation (delay in diagnosis) –Less rise in CD4
define Immune Reconstitution Inflammatory Syndrome (IRIS)
Start tx with very low CD4 count Experience a rapid CD4 and virologic response when started on antiretroviral therapy and
•Develop new clinical pathologies from a new or previously diagnosed opportunistic organism
pathogens responsible for Immune Reconstitution Inflammatory Syndrome (IRIS)
Mycobacterium avium, M. Tuberculosis
Cryptococcus, Leishmania
M. Leprae, Histoplasm
Kapsosi’s sarcoma, CMV, and JC virus (PML) are some of the organisms associated with IRIS
who is at risk for Immune Reconstitution Inflammatory Syndrome (IRIS)
Usually occurs in patients with CD4 nadir <400
Occurs in up to 36% of those with TB who are started on antivirals at diagnosis
- consider deferring ARV’s
name the Integrase strand transfer inhibitors (INSTIs)
Raltegravir - N, HA, D, – ↑ transaminases & CPK
Elvitegravir
Dolutegravir - Impaired glucose tolerance
Bictegravir
Cabotegravir/rilpivirine
name the nRTIs (Nucleos(t)ide reverse transcriptase inhibitors: “Nukes”
Tenofovir (TDF) - bone demineralization
Lamivudine (3TC) - Must check pt to make sure not HLA B*5701 positive
emtricitabine (FTC) - Must check pt to make sure not HLA B*5701 positive
Abacavir - hypersensitivity reaction
Zidovudine (AZT)
All NRTIs Adverse Effects:
Lactic acidosis and hepatic steatosis (higher incidence with stavudine)
Lipodystrophy, fat redistribution (higher incidence with stavudine, zidovudine)
Rash
Drug-drug interactions
HIV tx Can be added when all else failing.
Monoclonal anti-CD4 injection
new HIV med thatv has NO ORALS
Cabotegravir + rilpivirine – 2
Cabotegravir + rilpivirine - 3
pt taking abacavir what should you warn them about?
- severe rash/fever reaction and to stop rx immediately should such occur
- Ought not to occur if HLA B*5701 negative, but the world is not perfect.
after initiating HIV therapy what do we need to monitor?
when?
Check basic labs and viral load in 2-4 weeks.
One expects at least 10-fold (“one log”) decline in viral load.
describe
HIVPost-exposure prophylaxis – I
HIV Post-exposure prophylaxis – II
Post-exposure prophylaxis – I
- Occupational, e.g. healthcare worker, first responder – Sharps injury from HIV-positive or HIV-unknown
- Splash, saliva, urine, etc: Negligible risk.
Post-exposure prophylaxis - II Sexual contact
- We often end up giving rx even if statistics suggest low risk
- Truvada plus an INSTI for almost all cases
describe
- Pre-exposure prophylaxis (PrEP) – I
- Pre-exposure prophylaxis (PrEP) – II
Pre-exposure prophylaxis (PrEP) – I – Truvada (TDF)
- Serodiscordant couples
- Sex workers
- Other patients with high risk for sexual exposure
- Highly effective if taken daily – Requires close monitoring, harm reduction counseling regarding other STIs
PrEP - II
Issues – Very few end up adhering 100% on all days every week. Probably 4 days/week OK.
- Take two pills 2 to 24 hours before sex
- One pill 24 hours after the initial dose
- One final pill 24 hours later
- If pt has sex more than 24 hours after taking first dose (two pills), or over multiple days, continue taking one pill every day until pt has taken two doses following last anal sex encounter, at which point can stop.
PrEP - II timeline for sexual intercourse
Take two pills 2 to 24 hours before sex
One pill 24 hours after the initial dose
One final pill 24 hours later
If pt has sex more than 24 hours after taking first dose (two pills), or over multiple days:
- continue taking one pill every day until pt has taken two doses following last anal sex encounter, at which point can stop.
Name the ssRNA viruses
Zika - Flavivirus-
Dengue Virus (DENV) - Flavivirus
CHIKV - Alphavirus
transmission of Zika
Mosquito Bite - Aedes
- Aedes aegypti mosquito- tropical
- Aedes albopictus mosquito- temperate climates
- Aedes can also carry Dengue and Chikungunya viruses
Maternal-Fetal
Sex
Blood transfusions (likely, not confirmed)
Organ transplants
Lab exposure
transmission of dengue
Mosquito Bite - Aedes
Rare in organ donation or blood transfusion
maternal-fetal transmission - spread through breast milk
No Sex transmission
transmission of CHIKV
Mosquito Bite-Aedes ONLY
si/sx of Zika
Viremic period- Direct virus detection is 3-5 days after onset of symptoms
Symptoms (25%)- Resolve in 2-7 days
- Fever
- Maculopapular pruritic rash
- Headache
- Arthralgia _(small joints of hands/fee_t)
- Myalgia
- Conjunctivitis (non-purulent)
which virus has 4 serotypes
dengue
WHO 2009 revised classification of Dengue
Dengue w/o warning signs
Dengue w/ warning signs
Severe dengue –> Can lead to shock, internal bleeding and death in hours
dengue Warning signs:
- Abd pain
- Persistent vomiting
- Fluid accumulation
- Mucosal bleed
- Liver enlargement >2cm
- ↑hematocrit w/ concurrent rapid ↓PLTs
dx of Zika
rRT-PCR for Zika Virus RNA == Detects active infection
- Serum, urine (some assays use whole blood)
- ≤7 days of symptoms
Zika Virus IgM === If positive, need to do PRNT
- Also test for Dengue Virus IgM
- >7 days up to 12 weeks
Plaque Reduction Neutralization test (PRNT)
- Will tell you if Recent Zika Virus or false positive test
Tx of Zika
Supportive
acetaminophen
- NSAIDS avoided until Dengue ruled out to reduce risk of bleeding
- ASA avoided in children due to risk of Reye syndrome
Complications of Zika
Fetal loss
Microcephaly
Guillian-Barre Syndrome
Brain ischemia
Myelitis
Meningoencephalitis
phases of dnegue
Febrile Phase -3-7 days, after recover w/o complications
- Sudden onset ↑ fever ≥38.5C (101.3F)
- headache, eye pain, transient rash, vomiting, myalgia, arthralgia
- Conjunctival injection, pharyngeal erythema, LAD, hepatomegaly, facial puffiness, petechiae -hemorrhagic features
Critical Phase- Lasts 24-48 hrs (appears days 3-7 @defervescence) à children & young adults
- Systemic vascular leak syndrome- plasma leak, bleeding, shock, organ failure
- Abdominal pain, lethargy, persistent vomiting, clinical fluid accumulation, mucosal bleed
- Tachycardia, hypotension, AMS, oliguria, cool mottled skin, thready pulse
Recovery Phase - lasts 2-4 days
- Plasma leakage and hemorrhage resolve
- Additional pruritic rash may appear
- profound fatigue that may takes days to weeks to recover
dx of dengue
rRT-PCR for Dengue Virus RNA - Detects active virus infection within first 5 days
Dengue Virus antigen - active virus infection within first 7 days
Dengue Virus IgM - If positive, need to do PRNT
Plaque Reduction Neutralization test (PRNT) –
- Will tell you if Recent Dengue Virus or false positive test
- Can tell you serotype of Dengue
Dengue Virus IgG - Depends on primary vs secondary
lab findings in dengue during
Febrile Phase:
Critical Phase:
Recovery phase:
Febrile Phase:
- Leukopenia
- thrombocytopenia
- ↑ liver enzymes
Critical Phase:
- Moderate to severe thrombocytopenia
- US chest/abdomen for fluid
Recovery phase: Labs: Normalize
tx dengue
Supportive
Fever management – Acetaminophen
- No NSAIDS
Bleeding management- blood transfusions
Plasma leakage- volume replacement
Shock treatment
dengue prevention
Vaccination – Dengvaxia (Sanofi)
- Only for dengue seropositive or hx of Dengue
- ONLY if had dengue in past
si/sx of CHIKV
Incubation period: 3-7 days : Persistent and severe polyarthralgia is most prominent symptom
Acute phase: 7-10 days – show symptoms
- Begin abruptly with ↑fever – Duration 3-5 days .w/ Malaise
Polyarthralgia - 2-5 days after fever onset
- involves multiple joints- bilateral & symmetrical (hands, wrists, ankles
- Pain is intense and disabling
- Joint swelling, synovitis, joint effusions
Pruritic Macular or Maculopapular Rash
- Appearing 3 days or later after illness onset
- Starts on limbs and trunk
Dx: CHIKV
Most common lab findings??
RT-PCT for Chikungunya RNA virus - Detects active virus infection within first 5 days
Chikungunya Virus IgM - Detects recent infection
Chikungunya Virus IgG - Detects prior infection
Most common lab findings:
- lymphopenia & thrombocytopenia
complications of chikv
Persistent debilitating and immobilizing arthritis
- Some patients have persistent or relapsing disease (18 mo.-3 years)
Respiratory, renal and cardiovascular failure
tx chikv
Supportive care
NSAIDS ok, but if suspect Dengue, then need to wait 14 days from symptoms and no fever for 48hrs or warning signs
Steroids - Avoid during acute infection
Methotrexate - Post-acute and chronic arthritis
- After trial with with steroids & NSAIDs
Sulfasalazine if refractory to methotrexate
etiology of ebola (EBV)
Ebola has 5 species:
Filoviridae family (Filo meaning thread-like)
- Resembles rhabdoviruses (rabies) and paramyxoviruses (measles, mumps)
Ebola has 5 species
- Zaire
- Sudan
- Tai Forest (Ivory Coast)
- Bundibugyo
- Reston- animal reservoir only
who is most at risk for ebola
- Health care workers- most risk
- Burial Preparation- most risk
si/sx of ebola
Incubation period: 6-12 days post exposure
Symptoms: 2-21 days after contact (avg 8-10 days)
Symptoms start abruptly and progress from “Dry” to “Wet”
Dry symptoms (1-3 days)
- Fever
- aches/pains
- HA, myalgia, arthralgia, abdominal
- fatigue
Wet symptoms (3-10 days)
- Diarrhea, vomiting
- Volume loss contribute more to severe illness
Major hemorrhage is less common
Rash, red eye
dx ebola
Abnormal CBC- Leukopenia, Thrombocytopenia,
Abnormal CMP- Hyponatremia, hypokalemia, renal insufficiency, Elevated AST/ALT
Coagulation abnormalities- PT/PTT/INR prolonged
- Increase in fibrin degradation products i_n DIC_ (mostly in severe, fatal case)s
RT-PCR- Ebola viral RNA in serum
ReEbov- rapid immunoassay- detects virus antigen, used in field
- Results in 15 minutes
Ebola IgG
_____- Ebola viral RNA in serum
_______- detects virus antigen
- used in field
- Results in 15 minutes
RT-PCR- Ebola viral RNA in serum
ReEbov- rapid immunoassay- detects virus antigen
- used in field
- Results in 15 minutes
tx ebola
2 Medications for Zaire Ebolavirus
- Monoclonal Antibodies (Inmazeb, Ebanga)
Supportive care
ebola complications
Internal and External Bleeding (5-7 days after symptoms)
- Blood in stool, vomit, blood with coughing
- Petechiae, purpura, ecchymosis, hematoma, mucosal bleeding
Death (fatality rate ~50%)
- Shock from volume loss
- Shock from blood loss
- Multiorgan failure
ebola Prophylaxis: Vaccine
rVSV-ZEBOV (called Ervebo®)
list examples of each type of COVID vaccine:
mRNA Vaccines
Adenovirus Vector
Inactivated Virus
mRNA Vaccines
- moderna
- Pfizer
Adenovirus Vector
- J&J
- AstraZeneca/Oxford
- Sputnik V
Inactivated Virus
- Sinovac
- Sinopharm
how adenovorus vaccine work
Adenovirus is a dsDNA virus
Stable once assembled- standard Refrigerator
Issue is that if adenovirus carrying the vaccine is recognized by host from prior infection, then body will attack vaccine before it works
how inactivated virus vaccines work
Virus is killed but spike protein remains intact
Injected into body and antigen presenting cells
T cells detect surface proteins and activates B cells
B cells make antibodies to the virus
tx of COVID
Dexamethasone (High flow O2 or noninvasive vent)
Remdesivir Monotherapy (Low flow supplemental O2
Remdesivir with Dexamethasone (Low flow supplemental O2)
Remdesivir with Baricitinib (Low flow supplemental O2)
- Immunomodulatory effect with potential antiviral effect
- Used, if glucocorticoids CI
Adding Tocilizumab - Case by case basis
si/sx of sepsis
Hypotension SBP <90
Tachycardia >90 bpm
Tachypnea >20
Fever >100.9
risk fx for sepsis
- ICU admission
- Bacteremia
- Advanced age ≥65 years
dx sepsis
Leukocytosis <12 or leukopenia <4
Hyperglycemia >140
↑CRP, Cr, serum lactate, procalcitonin
Coag abnormalities
Thrombocytopenia <100
↓ PaO2
tx sepsis
Supplemental oxygen
Aggressive IVF
Peripheral access/Central access
Empiric broad-spectrum ABX within 1 hour tailored to patient
Vasopressors
Bacteremia common pathogens
S. aureus
s. pneumoniae
Group A Streptococcus
Enterobacteriaceae
Haemophilus influenzae
Pseudomonas aeruginosa
Possible blood cx contaminants
Coagulase negative staphylococci
Corynebacterium species (also referred to as ‘diphtheroids’)
C. (formerly Propionibacterium) acnes
Bacillus species
Micrococcus species
tx bacteremia
Empiric Antibiotics then NARROW
Antibiotic Prophylaxis
- At least 2 weeks - From first negative blood cultures
field mgt of Venomous Snake bites
1.Transport to a Medical Facility for ABCs and Antivenom
- Remove any areas of constriction (rings, clothing, ect)
- Clean with soap and water, cover with dry dressing
- Position bitten area - Neutral position at heart level, Can splint if needed
Hospital Mgt of snake bites
- ABCs- May need fluid resuscitation or vasopressors
- Mark area every 15 minutes until stable
- Labs: CBC, blood T&C, CMP, coags, CK, Other tests: ABG, ECG, CXR
•Specific antivenom administration - Call poison control, SnakeBite911 ER- phone app
•Acetylcholinesterase inhibitors if neurological dysfunction
Cnidarians bite SHOULD NEVER …
Do not rub area as may worsen release of adherent cnidocysts
how to remove spiculues of sea sponge
Dry skin
Use adhesive tape, commercial face peel or rubber cement
Vinegar 10-30 min q6-8h 4
Glucocorticoid or antihistamine cream
first steo when stung by annelid worms
Remove spines -use forceps, tape, face peel or rubber cement
complications of retained Sea Urchins spines
Can develop granulomas from retained spines
Eye contact can cause blindness
Sea Cucumbers
How Cone Snails cause death
Paralysis –> respiratory failure –> coma –> death
Blue ringed Octopuses si/sx & tx
Within minutes, oral and facial numbness –> total flaccid paralysis
Apply circumferential pressure dressing- preserve arterial pulse
most severe Scorpionfish that has antivenom
Stonefish > Scorpionfish > Lionfish
Stonefish antivenom available in severe cases
where is venom in marine catfish
Venom in dorsal spine and pectoral spines
Marine Vertebrate Sting Treatment
- Immerse affected part in non-scalding hot water for 30-90 min until pain relief
- Repeat pain = Repeat hot water immersion à Opioids and nerve blocks are ok
- Debride and clean wound (image if needed for FB)
- Mostly leave open to heal by secondary intention or delayed primary closure
- Consider tetanus and antibiotics
No evidence supports antihistamines or steroids