Infectious Disease #1 Flashcards
Tetanus, caused by Clostridium tetani (gram positive rod) is transmitted through the soil, and germinates especially in….
Explain the pathophysiology of this.
-Puncture and crush wounds
-Neurotoxin (tetanospasmin) blocks neuron inhibition by blocking release of GABA and glycine. This leads to severe muscle spasm.
Symptoms of Tetanus
-Local muscle spasms, neck or jaw stiffness, trismus (lockjaw)
-Trismus is earliest symptom
-May affect respiratory muscles
-Spasm
-Increased DTR’s
-Spatula Test: reflex spasm of masseter muscles instead of normal gag reflex when pharynx touched
-Pain and tingling of inoculation site
Treatment for Tetanus
-Metronidazole + IM Tetanus immune globulin (5,000 units)
What can be used to reduce spasms associated with Tetanus?
Benzodiazepines (Diazepam)
For Tetanus prophylaxis, if the patient was previously vaccinated, what should be given? When?
Tdap or Td vaccine booster every 10 years (or more than 5 years for major wounds)
If never vaccinated, what should be given?
-Tetanus immune globulin 250u + initiation of tetanus toxoid vaccine
True or False: a Tetanus booster is recommended for every pregnancy?
True
What is the vaccine schedule for Tetanus?
-5 doses given at 2, 4, 6, months of age, between 15-18 months and between 4-6 years old
Gas Gangrene, a life threatening muscle infection, is MCC by __________.
What are the symptoms of this condition?
Clostridium Perfringens
-Sudden onset of edema and extreme muscle pain + skin discoloration
-Bullae with blood tinged exudates
-Crepitus (Gas) in tissues on palpation
-Systemic toxicity (fever, chills, tachy, shock)
Radiographs for gas gangrene show…
-Air in the soft tissues
What is seen on culture or smear of exudates in gas gangrene?
-gram-positive bacilli with few leukocytes
Treatment for Gas Gangrene
-Emergent and aggressive surgical debridement (may need fasciotomy) + IV PCN + Clindamycin
Botulism, is a condition caused by ________.
What is the pathophysiology of this?
-Clostridium botulinum
-Neurotoxin inhibits acetylcholine release at the neuromuscular junction, leading to weakness, flaccid paralysis, and respiratory arrest
There are three common ways Botulism is transmitted…explain
-Adult: canned, smoked, and vacuum-packed foods
-Infant: ingestion of honey
-Wound: Puncture wound, IVDU
Symptoms of Botulism
-Symptoms occur 12-36 hours after ingestion
–8 D’s: Diplopia, Dysphagia, Dry Mouth, Dilated/Fixed Pupils, Dyarthria, Dysphonia, Descending Decreased muscle strength, decreased DTR’s
-Floppy Baby Syndrome: constipation followed by weakness, feeding problems, flaccid paralysis, weak cry
If Botulism is food borne, what is the treatment?
-Antitoxins
–> 1 year old: Equine derived
– <1 year old: human derived
If Botulism is wound related, what is the treatment?
-Antitoxin + Penicillin G
Symptoms of Diphtheria
-Tonsillopharyngitis or Laryngitis
-Myocarditis
-Pseudomembrane: friable grey to white membrane on pharynx that bleeds if scraped
-Cervical LAD
Treatment for Diphtheria
-Diphtheria antitoxin (horse serum) + Erythromycin or Penicillin x 2 weeks
-Respiratory droplet isolation
What should be given as prophylaxis for close contacts of those with Diphtheria?
-Erythromycin or Penicillin Benzathine G
The DTaP schedule is the same as in Tetanus for the vaccine. What is it?
5 doses at 2, 4, 6, 15-18 months, and 4-6 years old
Neisseria Gonorrhoeae is a ______________ bacteria that has symptoms such as ….
-Gram-negative diplococci
-Urethritis and Cervicitis: discharge, PID, epididymitis, prostatitis
-Triad of dermatitis, polyarthralgias, and tenosynovitis: rash, joint pain, tenderness along tendon sheath.
-Purulent gonococcal septic arthritis in the knee: in women, occurs during menses MC
What is the most sensitive and specific diagnostic for C. trachomatis, N. Gonorrhoeae?
Nucleic acid amplification taken at multiple sites (urethral, rectal, pharyngeal, cervical)
What is the treatment for Gonoccocal Infections?
Arthritis: IV Ceftriaxone
Urethritis or Cervicitis: Ceftriaxone 250mg IM + Doxy or Azithromycin
What else should you treat for when treating Gonorrhea?
Chlamydia, as they commonly co-infect
MC overall bacterial cause of STI in the US
Chlamydia Trachomatis
Symptoms of Chlamydia if…
-Urethritis:
-PID:
-Reactive Arthritis:
-Purulent discharge, pruritus, dysuria, dyspareunia, hematuria
-Abdominal pain, cervical motion tenderness
-Urethritis, uveitis, arthritis (HLA-B27)
Most sensitive diagnostic for Chlamydia
-NAAT (vaginal swab or first-catch urine preferred)
Treatment for Chlamydia
-Azithromycin or Doxycycline
-Also treat for Gonorrhea (Ceftriaxone)
What is Lymphogranuloma Venereum?
-Genital ulcer disease caused by Chlamydia Trachomatis
What are the symptoms of Lymphogranuloma Venereum?
-Painless genital ulcer at the site of inoculation
-Secondary stage: painful inguinal and/or femoral LAD (buboes)
-May develop proctocolitis (rectal discharge, constipation, fever, tenesmus)
Treatment for Lymphogranuloma Venereum?
-Doxycycline 100mg BIG x 21 days
Acute Rheumatic Fever MC affects….
Children 5-15 years old
What bacteria is involved with Acute Rheumatic Fever?
-Group A Strep (Strep Pyogenes)
Symptoms of Acute Rheumatic Fever (Remember JONES)
-Joint (migratory poly arthritis) = 2 or more joints, heat, redness, swelling, severe joint tenderness
-Oh my heart (active carditis) = heart condition including myocarditis, pericarditis, etc.
-Nodules (Subcutaneous) = seen over extensor surfaces, scalp, spinal column
-Erythema Marginatum = Macular, non-pruritic rash with sharp, annular borders on trunk and extremities.
-Sydenham’s Chorea = Sudden, involuntary, jerky purposeless movements involving head and arms.
What diagnostics can be done for Rheumatic Fever?
-Positive throat culture for GAS
-Rapid Strep Antigen
-Increased antistreptolysin O titers
Management for Rheumatic Fever
-Anti-inflammatory:
-ABX of choice:
-Aspirin (2-6 weeks)
-Penicillin G (or Erythromycin if PCN allergic)
What is the MC complication of Rheumatic Fever?
Rheumatic Valvular disease; MC mitral valve
Scarlet Fever is a diffuse skin eruption that occurs in the setting of a _________ infection
-Group A Strep (Strep Pyogenes)
Symptoms of Scarlet Fever
-Pharyngitis
-Fever, chills
-Diffuse erythema that blanches with pressure and multiple small papular elevations with sandpaper texture. Rash starts in axillae and groin and spreads to trunk and extremities (spares palms and soles)
-Circumoral pallor and strawberry tongue
Explain the rash in Scarlet Fever
Diffuse erythema that blanches with pressure and multiple small papular elevations with sandpaper texture. Rash starts in axillae and groin and spreads to trunk and extremities (spares palms and soles)
Treatment for Scarlet Fever
-Penicillin G or VK
-Macrolides (-mycins) if PCN allergic
Rocky Mountain Spotted Fever is a tick-borne disease caused by ___________
Some known vectors are __________________
Rickettsia rickettsii
Dermacentor andersoni and variabilis (wood and dog tick)
Where is RMSF MC in?
South-central and Southeastern US (Spring and Summer)
Explain the rash of RMSF
-Headache, fever, chills, malaise, myalgias
-Blanching, erythematous macular rash first on wrists and ankles (palms and soles common) then spread to trunk
-Rash starts as faint macules and becomes petechial.
-Periorbital and pedal edema
-Conjunctivitis
-Retinal abnormalities
-ARDS
RMSF is a clinical diagnosis, DO NOT wait for serologies. What is the treatment?
Doxycycline first line for non-pregnant and children
What is the treatment for RMSF is the patient is pregnant?
-Chloramphenicol
When should treatment for RMSF begin to reduce mortality?
ideally within 5 days of symptom onset
