Infectious Diseases Part 1 Flashcards
What type of bacteria is Clostridium Botulinum?
Anaerobic, gram-positive spore forming rod (Bacillus)
What is the pathophysiology of the botulism neurotoxin?
Neurotoxin inhibits acetylcholine release at the neuromuscular junction, leading to weakness, flaccid paralysis and respiratory arrest
What are the two most common transmission routes for Botulism?
- Adults: ingestion of toxin in canned, smoke, and vacuum-packed foods
- Infants: ingestion of honey before age 1
Symptoms of Botulism occur how long after ingestion of toxin
12-36 hours
Symptoms of Botulism
- Prodromal GI symptoms
- 8 D’s: Diplopia, Dysphagia, Dilated/Fixed Pupils, Dysarthria, Dysphonia, Descending Decreased muscle strength, Decreased DTRs
- Floppy Baby Syndrome: flaccid paralysis, weak cry, poor feeding
Diagnostics for Botulism
- Clinical
- Can be confirmed via toxin assay from stool, wound, or serum
Treatment of Foodborne Botulism
If > 1 year old: Equine-derived heptavalent antitoxin
If < 1 year old: human-derived botulism immune globulin
NO ABX IF FOOD DERIVED OR INFANTILE it may lyse the bacteria
If Botulism comes from a wound, what is the treatment?
Antitoxin + Penicillin G (Metronidazole if PCN allergy)
True or False: Campylobacter Jejuni is the MCC of bacterial enteritis in the US
True
What is the main source of Campylobacter Jejuni?
Contaminated food (raw or undercooked poultry), raw milk, contaminated water, dairy cattle. Puppies are an important source in children.
Symptoms of Campylobacter Jejuni
- Fever, crampy peri umbilical abdominal pain (may mimic appendicitis)
- Diarrhea that begins as watery and progresses to bloody
What shape bacteria is Campylobacter Jejuni?
S, comma, or “seagull shaped” gram-negative organisms
-Vibrio
What is the diagnostic of choice for Campylobacter Jejuni
Stool culture
Treatment for Campylobacter Jejuni
- Fluid and electrolyte replacement is mainstay of treatment
- In severe or high risk patients, Macrolides (Azithromycin) when needed
MC overall bacterial cause of STI’s in the US
Chlamydia
Symptoms of Chlamydia (remember associated with different conditions)
- Urethritis: purulent or mucopurulent discharge, pruritus, dysuria, hematuria
- PID: Cervical motion tenderness
- Reactive arthritis: urethritis, uveitis, arthritis
What is the diagnostic of choice for Chlamydia?
NAAT (vaginal swab or first catch urine)
Treatment for Chlamydia?
Azithromycin or Doxycycline
-Also treat for Gonorrhea with Ceftriaxone
Vibrio Cholerae (Cholera) is what shape bacteria?
Gram-negative comma-shaped rod
How is Cholera transmitted
Contaminated food and water
-Outbreaks occur during poor sanitation and overcrowding situations (abroad)
Symptoms of Cholera
-Copious watery diarrhea = rice water stools (gray with flecks of mucus and may have a fishy odor but no blood or pus)
Treatment of Vibrio Cholera
- Oral rehydration therapy and electrolyte replacement
- Tetracyclines
Symptoms of Diphtheria
- Tonsillopharyngitis or Laryngitis
- Myocarditis
- Pseudomembrane (friable gray white membrane on pharynx) that bleeds if scraped
- Cervical LAD with bull neck
Treatment for Diphtheria
- Diphtheria Antitoxin (horse serum) + Erythromycin or Penicillin x 2 weeks
- Place respiratory droplet isolation
Prophylaxis for Close Contacts of Diphtheria
-Erythromycin x 7-10 days or Penicillin G x 1 dose
Gonorrhea is what shape?
Gram-negative diplococci
Most sensitive diagnostic for gonorrhea
NAAT
Symptoms of Gonorrhea
-Urethritis: discharge, PID, prostatitis
-If the gonorrhea is disseminated, what are the symptoms?
-Triad of dermatitis, polyarthralgias, and tenosynovitis (tenderness along tendon sheath)
Purulent gonococcal septic arthritis occurs in which joint most frequently
The knee
Especially in women during menses
Treatment for Gonococcal arthritis
-IV Ceftriaxone
Treatment for Urethritis and cervicitis associated with gonorrhea
-Ceftriaxone 250 IM + Doxy or Azithromycin
What four medications are usually used Orally for treatment of MRSA
- Clindamycin
- Doxycycline
- Trimethoprim-Sulfamethazole
- Linezolid
IV: Vancomycin, Linezolid
Rheumatic Fever generally occurs in what age range?
Children 5-15 years old
Rheumatic Fever is due to an infection of
Group A Streptococcus (Strep Pyogenes)
The Jones Criteria is associated with Rheumatic Fever. Explain what is included in the JONES criteria MAJOR criteria
J: Joint (migratory polyarthralgia)
O: Oh My heart (active carditis)
N: Nodules (Subcutaneous)
E: Erythema Marginatum (macular, non-pruritic rash with clear borders on trunk and extremities)
S: Sydenham’s Chorea (Sudden, involuntary jerky purposeless movements)
What is included in the MINOR JONES Criteria?
- Fever
- Arthralgia (Joint Pain)
- Increased ESR/CRP/Leukocytosis
- ECG: Prolonged PR Interval
In regards to the JONES criteria, you need major and minor, PLUS what?
- Supporting evidence of a recent group A Strep infection
- -Positive throat culture
- -Rapid strep antigen
- -Elevated Strep Ab titers
Treatment for Rheumatic Fever
- Aspirin
- Penicillin G (Erythromycin if PCN allergy)
What is one major complication of Rheumatic Fever?
Rheumatic Heart Disease (mitral MC or aortic)
Rocky Mountain Spotted Fever is caused by what organism?
Rickettsia Rickettsii
What are two vectors of Rickettsia Rickettsii
Dermacentor Andersoni (Wood tick) & Variabilis (Dog Tick)
Where is Rocky Mountain Spotted Fever MC?
South-central and Southeastern US
Symptoms of RMSF
- Rash, headache, fever, chills, myalgias
- -Rash: blanching, erythematous macular rash on wrists and ankles (palms and soles) then spreads to trunk
- Periorbital or pedal edema in kids
- ARDS, cardiac problems, retinal abnormalities
True or False: RMSF is a clinical diagnosis and you should not wait for serologies?
True!
Treatment in a non-pregnant patient for RMSF
Doxycycline, even if < 8 years old
What is the treatment of choice for a patient who is pregnant with RMSF?
Chloramphenicol
-All treatment for RMSF should begin within 5 days of symptom onset to reduce mortality.
Causes of Salmonellosis
- Poultry, eggs, milk products, fresh produce
- Contact with reptiles
Symptoms of Salmonellosis
- nausea, vomiting, fever, abdominal cramping
- Pea soup diarrhea
- May be bloody, malaise, headaches
Treatment for Salmonellosis
- Oral rehydration and electrolyte replacement therapy (usually self-limited)
- Fluoroquinolones are first line when needed (-oxacin)
Shigellosis is caused by Shigella Sonnei. What is the shape of this bacteria?
-Gram negative rod (bacillus)
Which population is the most at risk for Shigellosis?
Children < 5 years in a daycare
Shigellosis is transmitted via fecal-oral route and is highly virulent. name some symptoms of this disease
- Lower abdominal pain
- Explosive watery diarrhea that progresses to mucoid/bloody diarrhea
- Febrile seizures
Diagnostics for Shigellosis
- Stool Cultures
- CBC: Leukemoid Reaction ( WBC > 50,000)
- Sigmoidoscopy: punctate areas of ulceration
Treatment for Shigellosis
- Oral rehydration and electrolyte replacement are mainstay
- Anti-motility drugs should be avoided (can worsen disease)
- Fluoroquinolones if severe (-oxacin)
Transmission of Tetanus
-In Soil; germinates especially in puncture wounds and crush wounds
Pathophysiology of Tetanus
-Neurotoxin blocks neuron inhibition by blocking release of inhibitory neurotransmitters GABA and glycine. This leads to severe muscle spasm.
Symptoms of Tetanus
- Local muscle spasms
- Neck of jaw stiffness (trismus)
- Risus sardonicus (facial contractions)
- Increased DTR
Treatment for Tetanus
- Metronidazole + IM Tetanus immune globulin
- Benzodiazepines to reduce spasms or IV Mag
Prophylaxis for patients with close contact with someone with Tetanus (both if vaccinated and if not vaccinated)
- If vaccinated: Tdap or booster every 10 years
- Never vaccinated: Tetanus immune globulin + tetanus toxoid vaccine
