ID Flashcards
1
Q
Factors that increase risk for fungal infection
A
- immunity
- Recent of current use of antifungal medication
- Risk of exposure
- Neutropenia (Invasive candidiasis and aspergillosis)
2
Q
List oppurtunistic
fungal infections
virus
Parasite
A
Fungus
- Cryptococcus
- Histoplasma
- Candida
- Pneumocystis
Virus - Cytomegalovirus
Parasite - Toxoplasma
3
Q
pathogen responsible for Criptococcus
A
C. neoformans and C. gattii
4
Q
transmission of Criptococcus
A
Transmission via air droplets and bird dropping
Spores are inhaled, lodge into the lung alveoli then disseminate hematogenously and cause infection
5
Q
Si/Sx of Criptococcus
what is most common??
A
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%)
6
Q
Dx & Tx of Criptococcus
A
Dx: cryptococcal antigen in CSF
Tx:
- Amphotericin B (80%)
- Fluconazole (50%).
7
Q
Tranmission of Histoplasmosis
A
inhalation & Exposure to chicken coop
8
Q
si/sx of Histoplasmosis
A
Fever
weight loss
skin ulcers
Hepato-splenomegaly
lymphadenopathy
9
Q
Dx & Tx of Histoplasmosis
A
Dx: Urine: H. capsulatum antigen sensitivity 95%
Tx:
- Amphotericin B an/or
- Itraconazole total 12 weeks
10
Q
the strain causing the disease is from the patient’s own GI flora
A
Candidiasis
11
Q
2 types of canidiasis
CD4 counts?
A
Oropharyngeal candidiasis (OPC) - CD4 <300.
Esophagitis - CD4 <100.
12
Q
types of Oropharyngeal candidiasis (OPC)
A
- Erythematous
- Hyperplastic
- Angular Cheilitis
- Pseudomembranous
13
Q
tx of Candidiasis
avoid??
A
Itraconazole (97%) or Fluconazole (87%)
Avoid topical treatments (nystatin)
- Lower cure rates
- Higher relapses rates
14
Q
the most common cause of dysphagia and odynophagia in AIDS.
A
Esophageal candidiasis
15
Q
Dx & Tx of Esophageal candidiasis
A
Dx: EGD
Tx: Fluconazole - If unable to swallow use IV
16
Q
pathophys of Pneumocystis Jirovecii
A
unique tropism for the lung and rarely invading the host.
•By attaching to the alveolar epithelium cause inflammation, interstitial edema and diffuse alveolar damage
17
Q
si/sx of Pneumocystis Jirovecii
A
Gradual onset and progression of
- Fever
- dry cough
- dyspnea.
Average 1 month before medical consultation
18
Q
Dx of Pneumocystis Jirovecii
best imaging & best lab??
A
Best imaging test: HRCT chest.
- If normal no PCP
Best lab test: BAL+ immunofluorescence
19
Q
tx of Pneumocystis Jirovecii
A
TMT-SMX
Adjunctive steroids if PO2 <70
20
Q
most important form of Cytomegalovirus
A
CMV can affect mainly retina ( the most important form of CMV), CNS and GI tract. Rare in lung.
CMV retinitis
21
Q
si/sx of CMV retinitis
A
- 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
22
Q
Dx & Tx of CMV retinitis
A
Dx: Perivascular fluffy yellow-white retinal infiltrate +/- hemorrhage
Tx: IV Ganciclovir , lifelong
23
Q
pathogen for Toxoplasmosis
A
30% of people in USA are seropositive (IgG) for T. gondii.
24
Q
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
A
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
25
Si/sx of toxoplasmosis
HA
Confusion
Fever
Lethargy
Seizure
Focal Sign
AMS
Psychomotor Retardation
Menignismus
26
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_
27
Tx toxoplasmosis
**Pyrimethamine+ Sulfadiazine + Leucovorin**
_Brain biopsy_ - if no clinical or radiological improvement after 14 days of anti-Toxoplasma therapy.
28
Most common tick-borne illness in the US & Europe
Lyme Dz
29
pathogen responsible for lyme
US
Europe & Asia
Borrelia burgdorferi in the US
Borrelia afzelii and Borrelia garinii in Europe and Asia
30
Si/Sx of Lyme
## Footnote
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
31
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
32
Tx of lyme
**Doxycycline**
Later in dz --\> IV abx
_Alt_: amoxicillin or ceftriaxone
33
Criteria for Lyme prophylaxis (ALL):
1. Attached tick identified as adult or nymph I. scapularis and attached for \>36 hours
2. Prophylaxis can be started within 72 hours of the time the tick was removed
3. Ecologic information indicated local rate of infection of ticks is ≥ 20%
4. Doxycycline is not contraindicated
34
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
35
si/sx of babeosis
Babesia can infect and destroy RBCs -\> **hemolytic anemia**
**Jaundice, dark urine**
Rash is UNCOMMON
Life threatening to asplenic patients
36
Dx of babeosis
_peripheral blood smear_
* On smear may look like Malaria – _look for the tetrads and extra cellular mezozites._
* **no hemozoin pigments.**
37
Tx of babeosis
Atovaquone + Azithromycin;
OR
Clindamycin + Quinine
*Educate the patient to not donate blood products*
38
transmission of Ehrlichiosis
Lone star tick
Blacklegged tick
Blood transfusions
39
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
40
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
41
Dx differentiation b/w
## Footnote
Ehrlichiosis
Anaplasmosis
**Ehrlichiosis**: Peripheral Smear – see the bacteria in _leukocytes_
**Anaplasmosis**: Peripheral Smear – see bacteria in _monocytes_
42
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
## Footnote
Spread from the bite of an infected tick
**Rare cases can be spread thru blood transfusions**
43
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%)
44
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
45
tick borne illness that:
Loves endothelial cells --\> inc permeability --\> leaky blood vessles
Rocky Mountain Spotted Fever
46
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
47
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.
48
Tx of rocky mtn spotted fever
Doxycycline
Chloramphenicol – safe in preg up to 3rd tri
Continue abx for 3 days after patient becomes afebrile
49
Complications of rocky mtn spotted fever
* Encephalitis
* Noncardiogenic pulmonary edema
* Adult respiratory distress syndrome
* Cardiac arrhythmias
* Coagulopathy
* Gastrointestinal bleeding
* Skin necrosis
50
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
51
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
52
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
53
\*Anopheles mosquito→P. falciparum & P. vivax
transmitted from a female Anopheles gambiae mosquito
* P. falciparum most commonly transmitted disease
* 2nd is P. vivax
Malaria
54
sporozoites goes to the liver within 1 to 2 hours and can remain dormant for years asymptomatic for 12 - 35 days --\> invade RBCs
Malaria
55
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
56
dx malaria
Rapid diagnostic test (**RDT**) : _if + →blood smear_
* **Evidence of hemozoi**n – 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
57
tx of malaria
Chloroquine
Malarone (atovaquone + proguanil) - NIGHTMARES
Coartem (arthemether + lomefantone)
Mefloquone
Quinine + Doxycycline, Clindamycin or Tertacycline
58
Most severe encephalitis in America
EEE
## Footnote
Dead-end hosts are HUMANS, EQUINE, SWINE, PHEASANTS
59
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
60
si/sx of EEE
“Encephalitis”
61
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
62
tx of EEE
No antiviral drug has proven beneficial
Supportive care
**Steroids worse outcomes!!-avoid**
63
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.
64
cayse of west nile
**Culex species of mosquito most common**
West Nile can infect birds, dogs and other mammals
Humans are “Dead-end” hosts
65
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
66
Dx & Tx of west nile
Dx:
## Footnote
**CBC** – leukocytosis
**Serological detection in blood and CS**F – 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.
67
pathogen responisble for tularemia
Francisella tularensis – infected animals
Inhale, touch, rub eye
68
si/sx of tularemia
RAPID ONSET
Late presentation specific manifestations:
**Ulceroglandular tularemia** – skin lesion with adenopathy
**Glandular tularemia** – tender regional lymphadenopathy
**Oculogladular tularemi**a – infection involving the eye
**Pharyngeal tularemia** – infection involving mouth or throat
**Pneumonic tularemia** – pulmonary involvement
**Typhoid tularemia** – systemic illness
69
dx of tularemia
**F. tularensis serology** – initial presentation and 2-4 weeks after
Culture and gram-stain – rarely positive
70
tx of tularemia
mild
severe
severe complications
**Mild illness:**
* Doxycycline
* Ciprofloxacin
**Severe illness**:
* Streptomycin
* Gentamicin
**Severe complications** : Meningitis & Endocarditis
71
si/sx of plague
## Footnote
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
72
dx plague
Chest x-ray -
* Bronchopneumonia
* Consolidation
* Cavities
* Pleural effusions
Culture and staining
Blood serology
Rapid test
73
Tx of plague
_Drug of choice:_ Streptomycin IM
* _Alt:_ Doxycycline or Tetracycline
_ISOLATION_
74
3 important diagnostic clues of plague
1. Presence of fever in a person with known contact with dead rodents or travel to plague-endemic region
2. Presence of fever, hypotension, and unexplained regional lymphadenitis
3. Presence of clinical findings of pneumonia in association with hemoptysis and sputum containing gram negative rods
75
•Intense pain and swelling LNs makes you think??
Bubonic plaque
76
Erythema migrans (EM) – bullseye rash
dx?
Lyme
77
hemolytic anemia, Jaundice, dark urine
dx?
Babesiosis
78
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
79
Hydrophobia & Aerophobia & "goose flesh"
Dx
Encephalitic rabies
80
Encephalitic rabies has (hypo/hyper) reflexia
Paralytic rabies has (hypo/hyper) reflexia
**Encephalitic** rabies has _HYPERreflexia_
**Paralytic** rabies has _HYPOreflexia_
81
Cycle of cold, hot, sweating -- cyclical fever!!
Dx
severe prrsentaion?
malaria
## Footnote
Severe Clinical Presentation: “cerebral malaria” – confusion, obtunded, seizures, coma
82
50% maculopapular rash on trunk
dx?
West Nile
83
Main HIV risk for males vs frmales
MSM main risk for males
heterosexual transmission for females
84
HIV Transmission Risk Fx:
↑Viral load
Lack of circumcision
STDs
Sexual partner number, practices
(Genetic)
85
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
86
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)
87
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)
88
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
89
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.
90
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.
91
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)
92
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
93
How does HIV present differently in Elderly??
Tend to have lower CD4 counts at presentation (delay in diagnosis) –Less rise in CD4
94
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
95
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
96
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
97
name the Integrase strand transfer inhibitors (INSTIs)
**Raltegravir** - N, HA, D, – ↑ transaminases & CPK
**Elvitegravir**
**Dolutegravir** - Impaired glucose tolerance
**Bictegravir**
**Cabotegravir/rilpivirine**
98
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)**
99
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**
100
HIV tx Can be added when all else failing.
Monoclonal anti-CD4 injection
101
new HIV med thatv has NO ORALS
Cabotegravir + rilpivirine – 2
Cabotegravir + rilpivirine - 3
102
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.
103
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.
104
describe
## Footnote
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 - I**I Sexual contact
* We often end up giving rx even if statistics suggest low risk
* Truvada plus an INSTI for almost all cases
105
describe
## Footnote
* 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.
106
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.
107
Name the ssRNA viruses
Zika - Flavivirus-
Dengue Virus (DENV) - Flavivirus
CHIKV - Alphavirus
108
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
109
transmission of dengue
Mosquito Bite - Aedes
Rare in organ donation or blood transfusion
maternal-fetal transmission - spread through breast milk
**No Sex transmission**
110
transmission of CHIKV
Mosquito Bite-Aedes ONLY
111
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)**
112
which virus has 4 serotypes
dengue
113
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
114
dengue Warning signs:
* Abd pain
* Persistent vomiting
* Fluid accumulation
* Mucosal bleed
* Liver enlargement \>2cm
* ↑hematocrit w/ concurrent rapid ↓PLTs
115
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
116
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
117
Complications of Zika
Fetal loss
**Microcephaly**
**Guillian-Barre Syndrome**
Brain ischemia
Myelitis
Meningoencephalitis
118
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
119
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
120
lab findings in dengue during
## Footnote
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
121
tx dengue
Supportive
Fever management – Acetaminophen
* **No NSAIDS**
Bleeding management- blood transfusions
Plasma leakage- volume replacement
Shock treatment
122
dengue prevention
**Vaccination -- Dengvaxia (Sanofi)**
* Only for dengue seropositive or hx of Dengue
* ONLY if had dengue in past
123
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
124
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_
125
complications of chikv
**Persistent debilitating and immobilizing arthritis**
* Some patients have persistent or relapsing disease (18 mo.-3 years)
**Respiratory, renal and cardiovascular failure**
126
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
127
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_
1. Zaire
2. Sudan
3. Tai Forest (Ivory Coast)
4. Bundibugyo
5. Reston- animal reservoir only
128
who is most at risk for ebola
* Health care workers- most risk
* Burial Preparation- most risk
129
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
130
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**
131
\_\_\_\_\_- 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
132
tx ebola
2 Medications for Zaire Ebolavirus
* Monoclonal Antibodies (Inmazeb, Ebanga)
Supportive care
133
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
134
ebola Prophylaxis: Vaccine
rVSV-ZEBOV (called Ervebo®)
135
list examples of each type of COVID vaccine:
## Footnote
**mRNA Vaccines**
**Adenovirus Vector**
**Inactivated Virus**
**mRNA Vaccines**
* moderna
* Pfizer
**Adenovirus Vector**
* J&J
* AstraZeneca/Oxford
* Sputnik V
**Inactivated Virus**
* Sinovac
* Sinopharm
136
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
137
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
138
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
139
si/sx of sepsis
Hypotension SBP \<90
Tachycardia \>90 bpm
Tachypnea \>20
Fever \>100.9
140
risk fx for sepsis
* ICU admission
* Bacteremia
* Advanced age ≥65 years
141
dx sepsis
Leukocytosis \<12 or leukopenia \<4
Hyperglycemia \>140
↑CRP, Cr, serum lactate, procalcitonin
Coag abnormalities
Thrombocytopenia \<100
↓ PaO2
142
tx sepsis
Supplemental oxygen
Aggressive IVF
Peripheral access/Central access
Empiric broad-spectrum ABX within 1 hour tailored to patient
Vasopressors
143
Bacteremia common pathogens
**S. aureus**
s. pneumoniae
Group A Streptococcus
Enterobacteriaceae
Haemophilus influenzae
**Pseudomonas aeruginosa**
144
Possible blood cx contaminants
**Coagulase negative staphylococci**
**Corynebacterium species (also referred to as 'diphtheroids’)**
C. (formerly Propionibacterium) acnes
Bacillus species
Micrococcus species
145
tx bacteremia
Empiric Antibiotics then NARROW
Antibiotic Prophylaxis
* At least 2 weeks - From first negative blood cultures
146
field mgt of Venomous Snake bites
1**.Transport to a Medical Facility for ABCs and Antivenom**
2. Remove any areas of constriction (rings, clothing, ect)
3. Clean with soap and water, cover with dry dressing
4. Position bitten area - Neutral position at heart level, Can splint if needed
147
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
148
Cnidarians bite SHOULD NEVER ...
Do not rub area as may worsen release of adherent cnidocysts
149
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
150
first steo when stung by annelid worms
Remove spines -use forceps, tape, face peel or rubber cement
151
complications of retained Sea Urchins spines
Can develop granulomas from retained spines
152
Eye contact can cause blindness
Sea Cucumbers
153
How Cone Snails cause death
Paralysis --\> respiratory failure --\> coma --\> death
154
Blue ringed Octopuses si/sx & tx
Within minutes, _oral and facial numbness_ --\> total flaccid paralysis
Apply _circumferential pressure dressing_- preserve arterial pulse
155
most severe Scorpionfish that has antivenom
_Stonefish_ \> Scorpionfish \> Lionfish
_Stonefish_ antivenom available in severe cases
156
where is venom in marine catfish
Venom in dorsal spine and pectoral spines
157
Marine Vertebrate Sting Treatment
1. Immerse affected part in non-scalding hot water for 30-90 min until pain relief
2. Repeat pain = Repeat hot water immersion à Opioids and nerve blocks are ok
3. Debride and clean wound (image if needed for FB)
4. Mostly leave open to heal by secondary intention or delayed primary closure
5. Consider tetanus and antibiotics
No evidence supports antihistamines or steroids
