Clinical Cases Flashcards
Staph Aureus
Clinical: toxic shock syndrome, scalded skin syndrome, ritter’s disease in newborns, food poisoning
Diagnosis: blood culture gram +, catalase +, coagulase + (coagulase is the most diagnostic)
Group A strep:
clinical presentation: pharyngitis, impetigo (“honeycomb crust”), erysipelas, cellulitis
Diagnosis: Gram + chains, throat/nose culture, beta hemolytic, bacitracin sensitive; ASO+, anti-streptolysin O antibodies present
Staphylococcus Aureus
Clinical p: LOCAL: skin/subcutaneous: impetigo, cellulitis, folliculitis, furuncles, carbuncles, respiratory: pneumonia with cavitations
Clinical p: SYSTEMIC: acute endocarditis, meningitis, osteomylitis, septic arthritis
Diagnosis: blood culture gram + clusters, catalase +, coagulase + COAGULASE is the most diagnostic
Staphylococcus saprophyticus
Clinical presentation: young sexually active female, URI, cystitis
Diagnosis: gram+, catalase +, coagulase, novobiocin resistant
Staphylococcus epidermidis
clinical p: infection of indwelling medical devices
diagnosis: gram + clusters, catalase +, coagulase -, NOVOBIOCIN sensitive
Streptococcus Pyogenes: toxin mediated
Clinical p: scarlet fever “sandpaper rash”, strawberry tongue, toxic shock syndrome, necrotizing fascitis
Diagnosis: gram + cocci in CHAINS, throat/skin culture showing beta hemolytic, bacitracin sensitive. ASO+: anti streptolysin O antibodies present
Erythema Marginatum (E in JONES criteria of Strep. Pyogenes)
subcutaneous nodules, JONES criteria (the N). Part of diagnosis for Strep Pyogenes
Soon after birth, an infant develops seizures, a marked irritability, poor feeding, and fever. The infant’s birth records note a prolonged labor with premature rupture of membranes. An LP was done and the infant was started on antibiotics.
Blood culture:
Gram +
CAMP test was (+)
Hippurate test was (+)
Bacitracin resistant
Group B strep: Steptococcus agalactiae
most common cause of meningitis in newborns.
Also causes pneumonia and sepsis.
Neonates acquire in mother’s birth canal during vaginal delivery.
Mother’s vagina swabbed @ 35-36 weeks for group B strep
an elderly woman presented with a cough producing rusty-colored sputum, she complains of sharp right-sided chest pains, chills, and fevers. Physical exam: fremitus, dullness to percussion, bronchial breath sounds on the lower right side. CXR shows right lower lobe consolidation, and gram stain of sputum shows:
GRAM + diplococci
catalase-
alpha hemolytic
optochin sensitive
bile-soluble
1 cause of community acquired pneumonia in adults
Streptococcus phenumoniae
Attacks lower lobes
“rust colored sputum” and lobar pneumonia
other systemic infections caused by S. pneumoniae include osteomylitis, septic arthritis, endocarditis.
Asplenic patients especially susceptible because unable to revmoe Ab coasted organisms; sickle cell dx patients are also particularly susceptible
LOBAR PNEUMONIA/Otitis media+meningitis
Most common BACTERIAL cause of “MOPS”:
Meningitis
Otitis media
Penumonia
Sinusitis
http://jaoa.org/data/Journals/JAOA/932168/863fig.jpegA middle aged womean presents with low grade fever and general malaise. Physican exam results showed in the image below in additon to this (http://jaoa.org/data/Journals/JAOA/932168/863fig.jpeg) and this (http://medicalpicturesinfo.com/wp-content/uploads/2011/09/Janeway-lesion-1.jpg)
An echocardiogram indicates vegetations on the mitral valve. In the doctor’s office, she recounts a dentist appointment a few weeks ago and several bouts of sore throat as a child.
Lab tests:
Gram+
alpha hemolytic
optochin-resistant
Bile-insoluble
Streptococci viridans
This includes: strep mutans (associated with dental/carries infections), Strep intermedius (brain, abdominal abscesses)
Important systemic infection is subacute bacterial endocarditis (SBE)
Three images: splintering hermorrhages of the finger nails, Jane way lesions on the hand, and Roth spots on the retina
Veridians step group known to be a common colonoizer of previously damaged heart valves .
Intermedis often present in abscesses
