1 yo or 20yo

-respiratory spread

-complement deficiency, asplenia, hepatic disease, multiple myeloma are possible underlying conditions

-acute onset of fever, chills, arthralgias, myalgias

-rapid petechial rash/purpura fuminans

WHAT is it? What would you culture?

Neisseria meningitidis

CSF

• pneumonia in pre-existing lung disease
• fulminant bacteremic supraglottitis-swollen tongue
• meningococcal conjunctivitis
• complications resulting from hematogenous dissemination-osteomyelitis, pericarditis

Prophylaxis against meningococcal disease

who and what?

• college freshman living in dormitories
• microbiologists
• military recruits
• travelers to the belt
• people w/ complement component deficiencies, asplenia
• rifampin, ceftriaxone, azithromycin NOT fluoroquinolone
• VACCINE
• tetravalent polysaccharide capsule vaccine->T-cell indepedent antigens
• conjugate vaccine->Tcell dependent immune response in infants

• capsular vaccine is only temporary immunity
• Group B antigen is poorly immunogenic b/c it is like NA in human CNS
• Outer membrane proteins are immunogenic but too specific to create a vaccine

MTM-specialized chocolate-agar based

G: endocervix, urethra discharge

-rectum, urethra, pharynx, blood, skin lesions

M: CSF, blood, skin lesions, nasopharyngeal swabs, biopsies, rectal

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-colonies are mucoid wet appearing b/c encapsulated

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Oxidase test with cytochrome c

Neisseria is oxidase +

catalase variable

• fluorescent Ab tests-not sensitive
• coagglutination and other immunologic tests
• Nucleic acid amplification tests-current
• use genital swabs or urine sample
• ferments glucose only

Gonorrhea-ceftriaxone or 3G cephalosporins

follow up treatment w/ azithromycin or doxycyclin for chlamydia

NO fluoroquinolones

Meninitidis-penicillin and 3G cephalosporins

-small, fastidious, pale staining gram - bacilli

[image]

-Do not grow on sheep blood agar but grow on chocolate agar

-meningitis, otitis media, sinusitis, epiglottitis, tracheobronchitis, bacteremia, pneumonia

-satellite test for ID

Haemophilus influenza

requires X factor=hemin and V factor=NAD

How do you identify Haemophilus species?

Treatment for H. influenzae

1. hemolysis on horse blood agar

2. satellite test

3. determination of X and V requirements on TSA

4. carbohydrate utilization tests

Ampicillin or 3G ceph-parenteral

Amoxicillin

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satellite test

S. aureus lyses rbc's->X factor

S. aureus secretes V factor

on sheep agar

-Haemophilus species needs both V and X factor

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horse blood agar has no hemolysis

What is the haemophilus species?

-Papular lesion that becomes ulcerated w/ ragged, non-indurated and painful

-gray-yellow exudate w/ easy bleeding

-may have supperative inguinal lymphadenopathy

[image][image]

gram- with chain arrangement or school of fish arrangement

Haemophilus ducreyi with a chancroid

-inguinal buboes may need to be drained to prevent rupture and sinus formation

Isolating and IDing H. ducreyi

biochemistry-oxidase, catalase, carb, factor requirement, nitrate reductase, alkaline phosphatase

difficult to culture-chocolate agar w/ vancomycin to inhibit gram +

-incubate at 33C for 7-10 days

-high humidity and lower oxygen tension (candle jar)

pale gram - coccobacilli in railroad track or school of fish arrangement

Oxidase + (like Neisseria)

Catalase -

asaccharolytic

requires X factor

nitrate reductase +

alkaline phosphatase +

Fastidious Gram Negative Bacteria

AACEK Group

• Normal flora of the human upper respiratory tract
• slow growing
• capnophilic
• hemin enhances initial recovery
• grow only on enriched media-chocolate or blood
• No growth on MacConkey/EMB agar
• Fermentative-except Eikenella corrodens

AACEK are normal flora of the upper respiratory tract

• Bacteremia and endocarditis
• Head and neck infections
• Dental infections
• Pleuropulmonary infections
• Soft tissue infections
• cellulitis, fasciitis, "clenched fist" injuries
• Bone and joint infections
• CNS infections

Primary agent in Periodontal disease in adolescents and adults

AACEK

oxidase -

catalase +

non B-hemolytic

IND -

Nitrate reduction +

AACEK

slow growing and only on blood cultures

found in gingival sulci

associated w/endocarditis

• native valves
• prosthetic valves
• pacemaker lead wires

Ox +

Cat -

non B-hemolytic

IND +

Fermenter

NIT - 

Cardiobacterium hominis

gram stain from blood culture

Rosette and Clustered cell arrangements

• Ocular infections
• Head/neck infections
• Pleuropulmonary infections
• Intra-abdominal infections
• Endocarditis-Dental work or IV drug users
• Cellulitis and osteomyelitis

Highest in 6mo-4 years

Day-care common for transmission

Osteoarticular infection in children <3 yo

Bacteremia, osteomyelitis, septic arthritis

B-hemolytic

NIT RED -

Kingella kingae

-children often have underlying disease

Congenital heart disease, ALL

fastidious gram - nonmotile coccobacillus

biochemically inert

Grows on Bordet-Gengou and Regan-Lowe media

No growth on chocolate, blood, or enteric media

"stoccato cough," cyanosis, vomiting

pediatric population are more symptomatic

PCR is done for?

Bordetella pertussis in the paroxysmal stage

• 7-14 after infection b/c cough appears after prodromal/infectious stage
• complications: otitis, encephalopathy, hernia, rectal prolapse, secondary infections
• Convalescent stage should occur w/in 4 weeks of onset

• adenylate cyclase hemolysin-inhibits PMN chemotaxis and phagocytosis
• tracheal cytotoxin-damages epithelial cells and inhibits DNA synthesis
• heat-labile toxin
• lipopolysaccharide
• pertussis toxin-lymphocytosis that stimulates immune response
• filmanetous hemagglutinin
• pertactin-adherence and cytokine release
• fimbriae-adherence

"staccato cough"

small gram - coccobacillus

cat +

ox -

Urease + after 24 hrs

grows on Bordet-gengou, Regan-Lowe, and chocolate agar

• dog owner w/ dog recently in kennel
• IC patient has sepsis, meningitis, peritonitis, pneumonia
• Ox +/Cat +
• gram - motile bacillus
• grows on BG, RL, chocolate, and MacConkey
• asaccharolytic
• urease + in 4 hours

nonmotile gram - bacilli

facultative anaerobes

OX +/CAT +

NIT RED +

Fermentative

-think animals!

Pasteurella spp.

P. canis

P. dagmatis-dog bites

P. caballi-horse bites

P. gallinarum-chickens and sepsis, endocarditis in humans

P. bettyae-human GU tract, post-partum bacteremia, salpingitis, PID

• facultative, non-motile gram - bacilli
• grows on blood and chocolate but not MacConkey agar
• Ox +/Cat +
• IND +
• penicillin-susceptible
• bite and scartch from a cat

Pasteurella multocida

• may colonize the resp tract of vets
• mostly wound infection/cellulitis
• may be more severe and deep in IC (diabetics)
• resp tract infections: pneumonia, empyema, lung abscess
• bacteremia/endocarditis
• CNS infection-brain abscess
• Eye infections

Principal reservoir in goats

acquired by eating infected unpasteurized milk and cheese

Endemic to Arabia, LA, Peru, Mexico, Argentina, Spain, Italy, Greece

2-3 weeks after exposure->symptoms

fever, night sweats, chills, malaise

lymphadenopathy, hepatosplenomegaly

undulating fevers for weeks-months

grows on blood and chocolate agar but not MacConkey agar

small gram - non-hemolytic coccobacilli

Ox +/Cat +

asaccharolytic

Brucella melitensis

Brucellosis is a chronic disease that has a long treatment period to act on phagocytic cells

Best specimens for Brucella?

Ways to ID different species?

Blood and bone marrow

-organism is sequestered in granulomas in tissue and bone marrow (RES)

Complications can occur on every system!

-Species identification can be done by

1. urease production

2. susceptibility to aniline dyes

3. direct fluorescent antibodies to individual species

Ulceroglandular _

Glandular _

Oculoglandular _

Pharyngeal _

Typhoidal _

Penumonic _

Tularemia

-transmitted Amblyomma americanum tick or direct inhalation

Patient has general symptoms of chills, fever, malaise, anorexia, fatigue. Cough, chest and abd pain, vomiting, sore throat, and diarrhea.

Tick bite

Sputum is non-diagnostic

Chest Xray shows widened mediastinum.

TBlike granulomas on pleural biopsies

Pneumonic Tularemia

Francisella tularensis

• Blood, pleural fluids, lymph nodes, wounds, conjunctival swabs, tissue, respiratory tract secretions (NOT cough sputum)
• Culture on blood/chocolate agar and incubate for 3-4 weeks, but often falsely negative
• very small, non-motile, obligately aerobic, gram - coccobacilli
• ox -/cat +
• organism is dangerous for laboratory personnel
• ID w/ agglutination, DFA, or PCR

• Small, slightly curved fastidious, aerobic gram - bacilli
• very slow growing requires freshly prepared blood or chocolate agar media incubated in CO2
• growth in 25-37C
• reservoir in wide variety of animals
• Specimens-BA lesions, lymph node biopsies & aspirates; blood cultures w/ blind staining of media w/ acridine orange

• outbreaks, poor sanitation, poor hygiene=globally endemic
• no known vertebrate reservoir except man
• vector is human body louse
• cycling fevers
• small, slightly curved, very fastidious, aerobic gram - bacilli
• headache, eye pain, conjunctival injection, myalgias, arthralgias, hepatosplenomegaly and leukocytosis

Bartonella quintana

Trench fever

• Homeless alocholic man with fever, bacteremia, endocarditis
• IV drug user
• Pre-existing valvular damage
• Immunosuppressed patients have Bacillary Angiomatosis
• red papule w/ scaly "collarette" that enlarge to form violacious dome-shaped nodular lesions
• lesions may ulcerate and bleed
• Warthin-Starry silver stain

2 Bartonella?

Bartonella quintana and B. henselae

Urban Trench Fever

papule that becomes pustular a week after a scratch

fever/malaise

regional lymphadenopathy in axillary, cervical, and submandibular areas

Parinaud's Oculoglandular syndrome: Granulomatous Conjunctivitis

CSD Neuroretinitis: Papilledema Associated with Stellate Macular Exudates

Disease and Agent?

Bartonella henselae and Bartonella clarridgeiae

Cat scratch disease

• Adherent, white, "cauliflower like" colonies
• small slightly curved, pleomorphic gram - bacilli
• Ox -/Cat - except B. henselae is catalase variable
• biochemically inert otherwise
• asaccralytic
• very fastidious
• detection w/ antibodies

Bartonella spp.

• use indirect fluorescent antibodies esp for B. henselae and B. quintana (B. Clarridgeiae soon)
• cross-reactions w/ chlamydiae and Coxiella burnetii
• CSD is usually self-limited

Listeria spp.

Erysipelothrix spp.

Lactoacillus spp.

Corynebacterium spp.

Arcanobacterium spp.

Bacillus spp.

Nocardia spp.

Rhodococcus spp.

Listeria spp.

Nonsporeforming, facultative, gram + bacilli

motile at room temp

-blood cultures positive in meningitis in 75% of cases

-gram stain of CSF is mostly neg

-low CSF glucose or normal

-predominance of mononuclear cells

-replication in phagosome and propelled by actin to neighboring cells

-raw milk and vegetables, fish, poultry, resh and processed meats and fish, cabbage, cole slaw, soft cheeses, shrimp

-may cause self-limited febrile enteritis w/

• acute, less common nuchal rigidity, move disorders (ataxia, tremors, seizeures), fluctuating mental status=meningitis
• Neonatal sepsis/meningitis
• Meningitis or parenchymal brain infection in patients with underlying disease of adults>50
• Fever during 3trimester b/c it can cross the placenta
• self-limited febrile enteritis w/ N/V/D

Listeria monocytogenes

• non-sporeforming gram + bacilli
• soft B-hemolysis/CAT+/motile at 25/ BBE+-like L. innocua except hemolysis
• isolate from blood, CSF, amniotic fluid, genital tract, biopsies, tissue
• CSF gram stain is often neg, glucose is low, and predominanted by mononuclear cells
• blood cultures are 75% +
• cold enrichment for recovery from stool, food, or environmental specimens
• raw milk, vegs, meats, cabbage, soft cheeses

• Meningitis (neonatal, IC, adults>50)
• acute onset
• less common nuchal rigidity
• movement disorders (ataxia, tremors, seizures)
• fever in 3 trimester pregnancy
• TX-amp + gen/TMP/SMX

Erysipelothrix rhusiopathiae

• nonsporeforming gram + rods
• swine infected
• cat -/nonmotile/H2S +, bottle brush growth in gelatin stab culture

• sepsis and bacteremia
• native and prosthetic valve endocarditis

Lactobacillus

• gram +, nonsporeforming, slender rods
• glucose fermentation
• CAT-/OX-/H2S-/NIT-/IND-
• facultative-produce H2O2
• normal flora of the vagina, GI, oropharynx and other animals; in nature

• facultative strains may represent non-specific defense mechanism for prevention of bacterial vaginosis and candida vaginitis

[image]

• opportunistic agent
• endocarditis
• bacteremia in IC hosts (neutropenia, antibiotic usage, transplant, chemotherapy, invasive GI, resp tract, Gyn procedures)
• pleuropulmonary infections
• rare infections

Corneybacterium genus

• mycolic acids
• meso-DAP
• Cat +
• lipophilic variable
• "club"-shaped, nonmotile

Non-lipophilic

• C. diptheriae
• C. amycolatum
• C. striatum
• C. pseudodiphtheriticum

Lipophilic

• C. jeikeium
• C. urealyticum

-grows on both chocolate and RBCs

-grows on trypitcase-soy agar

Cornyebacterium diphtheriae

• non-lipophilic gram + club shaped bacteria
• grey-white smooth nonhemolytic colonies on SBA
• toxin associated w/ lysogenization w/ B-corynephage
• AB toxin-ADP-ribosylates the EF-inhibits protein synthesis
• culture of throat or cutaneous specimens grows black colonies w/ brown haloes on cystine tellurite agar
• place swabs on Loeffler's coagulated serum medium-beaded appearance
• NIT +/Glucosidase +/Urease -/ GLU, RIB, MAL +
• Elek test for toxin detection

• diphtheritic "pseudomembrane" in posterior oro- and nasopharynx
• cutaneous diphtheria mistaken for anthrax
• both toxic and nontoxic strains associated w/ endocarditis and serious infection in IV drug users

C. amycolatum

• lacks cell wall mycolic acids
• forms dry, matte,"waxy" and "wrinkly" colonies on blood agar
• isolated from wounds, blood, joint fluid, bone, and UT
• NIT-/PYZ-/ALKPAL+/GLU, RIB, SUC +
• same as C. striatum

fatal sepsis in a premature infant

C. striatum

non-lipophilic/API like C. amycolatum

creamy, white, target colonies on BA

found in human nares and on skin

OI-bacteremia and endocarditis

wound and conjunctival infections

colonization of prosthetic devices

C. pseudodiphtheriticum

• NIT-/PYZ-/PYR-/PAL+
• Urease+ in 24 h
• asaccharlytic

-resp tract infections in IC hosts

-endocarditis on valves

wound infections

Tx-B-lactam, vancomycin, and aminoglycosides

Corynebacterium jeikeium

-lipophilic

NIT-/PZY and PAL+/URE-

GLU and RIB +

-colonizes the skin of hospitalized

-Infection in IC, neutropenia, indwelling medical devices

-under arm or groin area

C. urealyticum

lipophilic, small gray nonhemolytic colonies at 24h

-URE+ Rapidly (w/in mins)

-asaccharolytic

found on skin of humans and animals

acute and chronic UTIs in elderly, IC, and animals

-urolithiasis and alkaline-ecrusted cystitis in those w/ pyelonephritis (struvite)

-osteomyelitis, bacteremia, endocarditis, soft tissue and wound infection

Arcanobacterium haemolyticum

lipophilic, gram+ bacillus

CAT-

small, dull colonies after 48h showing "soft" B-hemolysis

pharyngitis and wound infections in children and young adults

"scarlatinaform rash"

-may be mistaken for group A strep pharyngitis

Bacillus spp.

gram + (variable) rods

Endospore forming under aerobic conditions

CAT+

Virulence factors of B. anthracis

produces toxins of 3 proteins (PA, EF, LF)

PA-binds to target cell receptors and aggregate to form ring-shaped hexamers->pores through the target cell membrane

EF and LT-inhibit phagocytosis, block oxidative burst of PMNs and increase intracellular cAMP levels

LT in macrophages-inhibits macromolecular synthesis, promotes apoptosis and hydrolyzes protein kinases involved in singal transduction

Capsule-resides on second plasmid-inhibtis phagocytosis

synthesis influenced by levels of CO2 and bicarbonate

Bacillus anthracis

• swabs/biopsies from supsected eschars
• stool, blood, hemorrhagic fludis from nose, mouth or anus, aspirates from peritoneum, spleen, mesenteric lymph nodes, paired serum specimens
• gram+ broad rod; oval central/subterminal spores
• non-hemolytic, ground glass w/ "egg white" consistency and "Medusa-head" margins
• Negative motility and neg hydrolysis of gelatin
• India ink + (capsules)
• CAT+ 

• cutaneous anthrax-most common; spores under skin; small papules that ulcerate surrounded by vesicles; painless eschar w/ edema
• GI-fever, acute gastroenteritis, vomiting, bloody diarrhea, intestinal eschar-bleeds, generalized toxemia
• Inhalational-spores; 1-2days high fever, dyspnea, hemorrhagic; mediastinal widening 
• NO pneumonia
• tx-penicillin except inhalation

Bacillus cereus and other nonanthrax spp.

• B-hemolytic
• motile
• hydrolyzes gelatin

• diarrheal syndrome-LT; abd pain w/ watery diarrhea after ingestion of meat, veg, cakes, suaces, dairy products
• emetic syndrome-LT; N/V w/ fried rice dishes left out in a buffet

Nocardia

• smears are only <50% sensitive
• invasive techniques for diagnosis-bronchalveolar lavage, TTA, bronchoscopy, bronchial brushings
• scans may show mass lesion in the brain w/ a normal CSF
• gram stain-beaded, 90degree branching
• Modified AFbacilli and lysozyme resistant
• Culture-blood, CSF, aspirates, sputum, and other resp tract specimens
• colony is white, tan, orange, pink; dig into the agar to remove, cerebriform powdery surface and musty, earthy odor
• ID w/ HPLC b/c hydrolysis tests are timeconsuming

-infections in IC hosts beginning in the lung->blood, skin, and CNS (brain abcess)

-assc w/ malignancies, chronic pul disease, collagen vascular disease, transplantation, diabetes and HIV

-SUBQ infection following traumatic implantation

Rhodococcus equi

• clear-to-white, nonhemolytic and frequently mucoid, often turning salmon-pink to red (4-7 days)
• asaccharolytic, NIT variable, URE+
• blood cutures w/ be + in IC hosts

-slowly progressive penumonia w/ lobar infiltrates progressing to cavitating lesions

IC infection