haemophilus/fastidious

hemin, hematin

NAD

• GN coccoid/rod

• non motile

• aerobic to facultatively anaerobic

• nitrate reduction

• ox pos, cat pos

10% normal flora of URT

• adherence: pili

• capsule: serotypes a-f (type b concern)

  • ribose, ribitol, phosphate = antiphagocytic and anticomplement

• IgA protease

• outer membrane proteins/LPS (paralyze the cilia so can’t clear lungs)

• causes disease in children

• unvaccinated kids get meningitis

• the vaccine has lowered incidence of disease

• invade the resp tract and tissues located around same area

• localized infections: pink eye, otitis media, sinusitis

• meningitis

• epiglottitis

• septicemia, septic arthritis, pneumonia

• invasion of resp tract

• bacteremia: spread to meninges and CSF

• infants/kids 3mos-6yrs

• acute inflamm and swelling causing airway obstruction

• affects kids 2-4yrs

• emergency tracheostomy

pinkeye: acute, contagious, purulent conjunctivitis

• pinkeye

• brazilian purpuric fever (BPF): warm tropical climates in kids

  • recurrent conjunctivitis, high fever, petechiae, purpura, septicemia, shock

  • mortality up to 70%

• STI: chancroid

• 4-14 day incubation

• painful lesion with irregular edge on genital/perianal areas

• enlarged and draining lymph nodes (buboes)

• very low incidence of pathogenicity

• rarely implicated in endocarditis

may cause some pharyngitis in absence of other pathogens

• bite wound infections, endocarditis

• reclassified as aggregatibacter (HACEK)

• dies rapidly so plate w/in 10 min

• ducreyi: clean specimen site with sterile saline/gauze and swab base of ulcer

• inoculate primary plates plus additional media for suspecting haemophilus

  • BAP only have X

  • CHOC has X and V (heat deactivates NADases)

  • no MAC growth

CHOC with bacitracin: inhibits other resp normal flora

CHOC with 1% isovitalex (choc usually comes with this already)

GC agar (hgb, fetal bovine serum, vanc - all reduce normal genital flora)

• h. hemolyticus, parahaemolyticus, sometimes ducreyi are beta hemolytic

• lack NADases so factor V is available (allows growth and hemolysis)

• keep humid and capnophilic to prevent drying

• GN pleomorphic usually more ccb than rods

• intra and/or extracellularly

• grows on CHOC, no BAP/MAC

• translucent, moist, smooth, convex

• mousy odor

• encapsulated strains are more mucoid

• influenzae and others: GN ccb and rods longer than the direct smear

• ducreyi: GN ccb arranged in groups (school of fish)

• ox pos, cat pos

• non motile

• nitrate reduction

• satellite test pos (except in aphrophilus and ducreyi)

• grow in nutrient broth, lawn streak a mueller hinton and add X, V, XV strips

• incubate 35-37C, 5-10% CO

• read and record where growth occurs

• speciates based on X/V requirements and horse blood hemolysis

• add loopful suspension to each quadrant and incubate with CO2

• Q1 = X factor

• Q2 = V factor

• Q3 = XV factor

• Q4 = V, horse blood

• if no X required = ALA is produced

  • PBG made from ALA via PGB synthase and converted to protoporphyrin IV which is the precursor to X factor

• detect porphyrin presence with wood’s lamp

  • tube: add organism with ALA reagent and incubate, add kovac’s and observe

    • red fluoro = pos (hemin not required)

  • agar

  • rapid disk 2hr incubation

• cefotaxime or ceftriaxone recommended

• alternative: bactrim, imipenem, cipro, chloramphenicol

  • amp was used but now there is resistance

    • check nitrocefin to check

• ducreyi: erythromycin, cipro, ceftriaxone, azithromycin

• GNR

• capnophilic

• significant cause of endocarditis (heart valves)

• normal flora in oral cavity (bite wounds/subacute endocarditis)

• opportunists in immunocomp

• foam loving

• most involved HACEK member in endocarditis

• animal pathogen but found in human oral cavity

• capnophilic; up to 72 hrs to grow

  • distinctive star formation in center of colonies

• SBE: wound infections, bacteremia, dental infections

• ferments carbs in presence of serum (not lactose/sucrose)

• cat pos, ox V

• no MAC growth

• neg urease, indole, esculin, citrate

• pleomorphic, nonmotile, GNR (looks GP sometimes)

• swollen at one end (tear drop, dumbbell, lollipop)

• rosette formation in gram stain

• normal flora of nose, mouth, throat

• exclusively endocarditis: aortic valve, prosthetic valves

  • resistant to antibiotics so must be replaced

• grows on BAP/CHOC in 3 days, not MAC

• capno, pitting possible

• ox pos, indole pos

• neg urease, cat, nitrate, gelatin, esculin

• normal flora in oral/bowel cavities (fight/bite wounds)

• periodontitis, meningitis, empyema, pneumonia, osteomyelitis, arthritis, post op infections, cellulitis (licked clean needles), endocarditis (least common in HACEK)

• capno with factor X (hemin)

• GN ccb, slender, fusiform

• bleach like odor, pale yellow colonies pit agar

• ox pos, cat neg, non motile

• ccb or short rods in pairs/chains (resistant to decolorization)

• nonmotile but may twitch

• ox pos, cat neg, sugar ferm

• predilection for bones/joints (osteoarthritis in kids <4yr)

• cause endocarditis

• may pit agar and grow on TM (resemble n. gonorrhoeae)

• nitrate pos

• neg urea, indole, citrate

• spreading, corroding or smooth, convex and beta hemolytic

• produced yellow brown pigment

• pos glucose, maltose

• neg nitrate

• pos X, V

• neg hemolysis, ALA

• pos V, ALA

• neg X, hemolysis

• pos X, V, hemolysis

• neg ALA

• pos V, ALA, hemolysis

• neg X

• pos X

• neg V, ALA, hemolysis