Infectious Diseases #5 Flashcards
Babesiosis is an infectious disease caused by Malaria-like protozoa of Babesia Microti. It is transmitted by
Ixodes Scapularis (same tick as Lyme Disease)
Risk Factors for Babesiosis
- Elderly
- Asplenia
- Immunocompromised
- Midwest and Northeast US
What is the pathophysiology of Babesiosis
Similar to Malaria, the protozoa infect and lyse red blood cells and lead to hemolysis
On a peripheral blood smear with Giemsa or Wright stain, what is seen with babesiosis?
Pathophnomonic tetrads (Maltese cross appearance) -Intraerythrocytic rings with central pallor
However, what is the most accurate test for babesiosis?
PCR for detection of Babesia DNA
Treatment for Babesiosis?
Atovaquone + Azithromycin
OR
Quinine + Clindamycin
Leishmaniasis is transmitted through
female Sand fly in Mediterranean, Central, South America and Asia
Symptoms of Leishmaniasis
- Localized cutaneous papule that has satellite pustules at bite site
- Mucocutaneous ulcers of the skin, mouth, and nose
- Hepatosplenomegaly
Treatment for Leishmaniasis
- Infectious disease consult
- Sores heal spontaneously
What is the cause and causative agent of Cat Scratch Disease?
- From scratch or bite from an infected cat or exposure to cat fleas
- Bartonella Henselae
Most common diagnostic used for cat scratch disease?
Serologic: via ELISA or Immunofluorescence assay
Treatment for Cat Scratch Disease
- Mild: Symptomatic and self-limited
- Azithromycin (first line) or Doxycycline
How is the Zika Virus transmitted?
Flavivirus transmitted by Aedes mosquito
Associated conditions to Zika Virus
- Guillan Barre Syndrome
- Congenital Zika Syndrome: microcephaly, intracranial cerebral malformation, ocular lesions
Initial test of choice for Zika Virus
-Serum or urine Zika virus IgM
What can be used as a screening test for Zika Virus in pregnant women?
Reverse-transcriptase PCR
Treatment for Zika Virus
Supportive: hydration, acetominophen
-Aspirin should not be used until Dengue Fever ruled out due to Reye Syndrome in kids
How is Tularemia transmitted?
-Rabbits, ticks, deer, deer flies
Symptoms of Tularemia
- Single papule at site of inoculation with central eschar formation and tender LAD
- At hand and arm most common after animal exposure
What is the drug of choice for Tularemia?
Streptomycin
Hot tub folliculitis is a benign self-limited condition with skin lesions caused by
Pseudomonas Aeruginosa
When does hot tub folliculitis happen?
-8-48 hours after exposure to water in a contaminated spa, swimming pool, or hot tub (especially made of wood)
Treatment for hot tub folliculitis
No treatment needed in most cases
-Ciprofloxacin orally if persistent
Q fever is caused by
Coxiella Burnetii
Transmission of Q fever
Inhalation of spores or ingestion. Exposure to farm animals and their products
-Individuals living downwind from farms and contaminated manure, straw, or dust
Main manifestations of Q Fever
- Pneumonia
- Culture negative endocarditis if Chronic Q Fever
Initial treatment of choice for Q Fever
Doxycycline
-Rifampin if chronic
Brucellosis, although rare in the US, is transmitted through
Ingestion of infected dairy products (unpasteurized milk, cheese) and consumption of undercooked meat
-veteranarians, farmers, contact with livestock
Symptoms of Brucellosis
- Undulent fever (rises and falls)
- Sweating (moldy, wet hay smell)
- Migratory arthralgia or myalgia
Treatment for Brucellosis
- Doxycycline + Rifampin in adults
- Bactrim + Rifampin in kids
Complications of Brucellosis
- Endocarditis (most lethal)
- Osteomyelitis of lumbar spine (most common)
Plague is caused by
Yersinia pestis (gram-negative rod)
Plague is transmitted through ______ and the MC form of plague is
flea bites (rodent fleas)
-Bubonic: acutely swollen, red, painful nodes (buboes) in groin, cervical, and axilla regions
Diagnostics for plague
-Gram stain from tissue: bipolar staining (safety pin appearance)
Treatment for plague
- Streptomycin or Gentamicin (1st line)
- Doxycycline second line
- Strict isolation for 48 hours after therapy begins
Anthrax, caused by Bacillus Anthracis, is naturally found in
Livestock
Symptoms of anthrax
-Erythematous papule at site of inoculation that runs into a painless black eschar
Treatment for Anthrax
-Fluoroquinolones (Ciprofloxacin)
Cytomegalovirus, also known as _____, is mostly seen in immunocompromised patients with a CD4 < ____.
HHV
< 50
What are some symptoms of reactivation of Cytomegalovirus HHV5
- Colitis (MC) in CD4 < 100
- Retinitis: hemorrhage with yellow white soft exudates, blurry vision when CD4 < 50
- Esophagitis: large superficial ulcers on endoscopy
Diagnostics for Cytomegalovirus HHV5
- Serologies: PCR
- Biopsy of tissues: owl eye appearance (epithelial cells with enlarged nuclei surrounded by clear zone and cytoplasmic inclusions)
Treatment for reactivation Cytomegalovirus HHV5
-Ganciclovir (first line)
What is given to HIV+ patients for prophylaxis against CMV HHV5 if CD4 <50?
Valganciclovir
What is the most common congenital viral infection?
Congenital CMV
Most common sequelae of CMV HHV5 congenital?
Sensorineural hearing loss
Listeriosis is caused by Listeria monocytogenes, a non-spore forming _________, gram-positive bacili
Endotoxin-producing
How is Listeriosis transmitted?
Contaminated foods (cold deli meats, hot dogs, unpasteurized dairy products such as soft cheese and milk)
Symptoms of Listeriosis
- Listeriosis: bacteremia and/or meningitis in infants < 2 months, elderly, and immunocompromised
- Febrile illness: fever, flu like symptoms
- Pregnancy: third trimester; febrile illness associated with premature labor, stillbirth, infected newborns
Diagnostics for listeriosis
Cultures: blood or CSF
Treatment for Listeriosis (not including meningitis)
- IV Ampicillin is initial management of choice (or Penicillin G)
- Gentamicin is added in meningitis, endocarditis, and immunocompromised
- Batrim if PCN allergy
Treatment for meningitis associated with Listeriosis
- if < 1 month old: Ampicillin + Cefotaxime + Gentamicin
- if > 50 years old: Ampicillin + Ceftriaxone + Vancomycin
Scarlet Fever (Scarlatina) is a diffuse skin eruption that occurs in the setting of _____ Infection
Group A Strep (Strep Pyogenes) infection
Symptoms of Scarlet Fever
- Pharyngitis, Fever
- Diffuse erythematous rash with a sandpaper texture (starts in axillae and groin and spreads to trunk)
- Circumoral pallor, strawberry tongue, flushed face
Treatment for Scarlet Fever
- Penicillin G or VK (first line)
- Macrolides if PCN-allergy
How long after antibiotic administration can children return to school with Scarlet Fever?
24 hours after starting ABX
