Infectious Disease Flashcards
Acute rheumatic fever
Autoimmune inflammatory process that develops as a sequela of streptococcal infection
Dx of acute rheumatic fever
There is no specific diagnostic test for dx
Focus is on prevention with tx of strep and avoid repeated untreated infections
Rheumatic heart dz
The most significant complication of acute rheumatic fever which occurs after repeated bouts of acute illness
Abx and rheumatic heart dz
Antibiotic therapy does not alter the course, frequency, or severity of cardiac involvement once a pt develops rheumatic heart dz
Clinical manifestations of acute reheumatic fever
Polyarthritis Carditis Erythema marginatum Chorea Subcutaneous nodules
PE of acute rheumatic fever
80% of pts present early on with painful migratory arthritis in large joint such as knees, ankles, elbows, or shoulders
Chorea is a rare late-onset sign
Carditis (with progressive CHF, a new murmur, or pericarditis) may be the presenting sign and most lethal
Work up of acute rheumatic fever
ASO titers should be combined with a careful clinical evaluation and other antibodies such as antistreptokinase and anti-DNAse.
Throat culture may only be positive in 25-40% at time of rheumatic fever
Tx of acute rheumatic fever
PCN: either an injection of benzathine benzylpenicillin, or pcn
OR
Oral cephalosporin if allergic to pcn and pt is ok with risk of 20% cross-reactivity and risk of allergic reaction with cephalosporin
Organisms of chlamydia
C. pneumoniae- mild pna or bronchitis in adolescents and young adults
-Older adults can have more severe infection
C. psittaci- Psittacosis after exposure to infected birds
-Transmission of both C. pneumoniae and C. psittaci is through repsiratory secretions
-Chlamydia causes 10-20% of cases of CAP
C. trachomatis- sexually transmitted
Hx/PE of chlamydia
Incubation period is 3-4 wks, with gradual onset of mild sx (low grade fever, rhinitis, laryngitis, pharyngitis, sinusitis) to more cough with scant sputum, then malaise, hoarseness and HA in 58%
Rhonchi and rales present even in mild dz
C. psittaci pneumonia when exposed to birds (sick birds) with high fever 103-105 degrees
Best test is isolation in sputum culture (for pts not responding to outpatient therapy)
Tx of chlamydia- non STI
Tetracyclines and macrolides are the drugs of choice
- Doxycycline if >9 yo and not pregnant- 100 mg BID x 10-14 days
- Clarithromycin 500 mg BID x 10 days (or azithromycin 500 mg daily for 7-10 days)
When to suspect STI chlamydia in women
If pt has deep internal pain with intercourse
With bimanual exam she will experience intense pain with manipulation of cervix
S/sx of chlamydia in women
May be asymptomatic and the onset often indolent. It can cause cervicitis, endometritis, PID, urethritis, epididymitis, neonatal conjunctivitis, and pediatric PNA
Tx for STI chlamydia
Azithromycin 1 g PO in a single dose (OK in pregnancy) OR
Doxycycline 100 mg PO BID x 7 days (NOT OK in pregnancy)
Alternatives:
Erythromycin base 500 mg PO QID x 7 days
OR
Erythromycin ethylsuccinate 800 mg PO QID x 7 days
OR
Ofloxacin 300 mg PO BID x 7 days
OR
Levofloxacin 500 mg PO once daily x 7 days
Gonorrhea
A purulent infection of ANY mucus membrane surfaced caused by N. gonorrhea, but usually affects the genital mucous membranes
What should occur in pts positive for any STI?
Should have a full eval for risk of other diseases such as Chlamydia, syphilis, Hep B and C, and HIV. If high risk- the pt should be tested.
But insurance may not always reimburse every time- pts need to be made aware of risk, cost, and importance of prophylaxis
Hx/PE of gonorrhea in females
Vaginal discharge: MC presenting symptom -Thin, purulent, and mildly odorous Dysuria Intermenstrual bleeding Dyspareunia Mild lower abdominal pain
Hx/PE of gonorrhea in females if it progresses to PID
Lower abdominal pain, the MC symptom of PID
Increased vaginal discharge or mucopurulent
Dysuria: usually without urgency or frequency
Cervical motion tenderness
Adnexal tenderness (usually bilat) or adnexal mass
Intermenstrual bleeding
Fever, chills, nausea, and vomiting (less common)
Hx/PE of gonorrhea in males
Urethritis: the major manifestation of gonococcal infection in men; initial characteristics include burning upon urination and a serous discharge; a few days later, the discharge usually becomes more profuse, purulent, and at times, tinged with blood
Acute epididymitis: Usually unilateral and often occurs in conjunction with a urethral exudate
Urethral strictures: Have become uncommon in the antibiotic era, but they can present with a decreased and abnormal urine stream, as well as with the secondary complications of prostatitis and cystitis
Tx of gonorrhea
Ceftriaxone 250 mg intramuscular single dose PLUS
Azithromycin 1 g PO single dose OR
Doxycycline 100 mg PO BID x 7 days
Diphtheria
Either an upper respiratory tract or cutaneous infection caused by aerobic Gram pos bacteria Corynebacterium diphtheria.
Occurs in spring or winter mos and continues for 2-6 wks without antibiotic tx
Who is susceptible to diphtheria?
Those not immunized or those with a weak antibody level exposed to diphtheria
Hx/PE of diphtheria
Sx start as nonspecific upper respiratory sx, then sore throat
Development of a localized pseudomembrane- dense, gray debris in the posterior pharynx
Removal of the membrane reveals a bleeding, edematous mucosa
Cervical adenopathy and swollen mucosa gives a bull’s neck appearance
Tx of diphtheria
Admit for tx
Horse serum antitoxin is given in early stages, then a macrolide
