decrease the risk of pneumococcal meningitis☆dexamethasone
dexamethasone prior to the antibiotics has shown to decrease the risk of adverse events(eg seizures, focal neurologic deficits) and death microbiologypharmacologyUWorld Jul 11, 2020, 1:04 AM HirotoShishido
when do anti-HIV antibodies, HIV p24 antigen, and plasma HIV RNA become positive?RNA→ 2 months after the first infection
p24→ 2 and half months
antibodies→ 3 months microbiologyUWorld Jul 11, 2020, 12:47 AM HirotoShishido
coxiella burnetiiSpores inhaled as aerosols from ☆cattle/sheep amniotic fluid. Presents with headache, cough, influenza-like symptoms, pneumonia, possibly in combination with ☆hepatitis.
Common cause of culture ⊝ endocarditis (especially with the patient with valver disease) microbiologyUWorld Jul 10, 2020, 8:49 AM HirotoShishido
EIEC, ETEC, EPEC, EHECEIEC invasion, bloody diarrhea, similar to Shigella
ETEC heat labile and stable, no inflammation Traveller's diarrhea
causative bacteria for pseudoappendicitisYersinia enterocolitica
Gram ⊝ ☆pleomorphic rod/coccobacillus.
Usually transmitted from pet feces (eg, puppies), contaminated milk, or pork.
Can cause acute bloody diarrhea, pseudoappendicitis (right lower abdominal pain due to mesenteric adenitis and/or terminal ileitis), reactive arthritis in adults. microbiology Jul 10, 2020, 7:54 AM HirotoShishido
toxins of Pseudomonas aeruginosaProduces PEEP:
Phospholipase C (degrades cell membranes→ C perfringens too!);
Endotoxin (fever, shock);
Exotoxin A (inactivates EF-2);
☆Pigments: pyoverdine and pyocyanin (blue-green pigment ; also generates reactive oxygen species). microbiologyUWorld Jul 10, 2020, 7:39 AM HirotoShishido
brucellaGram ⊝, aerobic coccobacillus.
Transmitted via ingestion of contaminated animal products (eg, unpasteurized milk).
Survives in macrophages in the reticuloendothelial system. Can form non- caseating granulomas. Typically presents with undulant fever, night sweats, and arthralgia.
Treatment: doxycycline + rifampin or streptomycin. microbiology Jul 10, 2020, 7:32 AM HirotoShishido
histopathology of actinomyces(actinomycosis)
Diagnosis is made by identifying the bacteria with unique filamentous, branching patterns and the characteristic sulfur granules, which are formed by calcified mycelial fragments.
Sulfur granules grossly appear yellow; however, hematoxylin and eosin staining gives them an ☆amorphous (rosette -like) basophilic (purple/blue) appearance under light microscopy. microbiologyUWorld Jul 10, 2020, 6:52 AM HirotoShishido
mecA geneencodes for penicillin binding protein (PBP) 2a
unlike other PBP, PBP 2a has ☆low affinity for beta-lactams and continues to cross link peptidoglycan in the presence of oxacillin, methicillin, ☆cephalosporins, and other beta lactam medications microbiologypharmacologyUWorld Jul 10, 2020, 5:07 AM HirotoShishido
P aeruginosa (☆cystic fibrosis pneumonia (adult, child→ S aureus), contact lenses)
Nontypeable (unencapsulated) H influenza (most common cause of mucosal infections like ☆otitis media, conjunctivitis, sinusitis) microbiologyUWorld Jul 10, 2020, 4:38 AM HirotoShishido
