AEROBIC GRAM-NEGATIVE BACTERIA: C. HAEMOPHILUS AND SIMILAR ORGANISM

Haemophilus & similar organism

a. Most are normal _______ biota

b. Members of HACEK are fastidious and important cause of _____

d. They typically inhabit the _____ of humans

e. Pleomorphic gram - ____ ranging from very small to filamentous

f. Growth requirements:

1. _____- released form Hemoglobin

2. _______ - heat labile

Haemophilus & similar organism

a. Most are normal UPPER RESPIRATORY TRACT biota

b. Members of HACEK are fastidious and important cause of endocarditis

d. They typically inhabit the oral cavity of humans

e. Pleomorphic gram - cocobacilli ranging from very small to filamentous

f. Growth requirements:

1. Hemin (X factor) - released form Hemoglobin

2. Nicotin Adenine Dinucleotide (NAD V factpr) - heat labile

• Exhibits satellitism 

• Do not grow on SBA because of NADase in the agar (it inactivates NAD) BUT grows on horse or rabbit blood agar which does not contain NADase

• Smooth, round, flat, opaque, and tan on Chocolate agar

Haemophilus spp.

• Motility = NEGATIVE

• Catalase, Oxidase = POSITIVE

• Chocolate agar is routinely used for culture

• Grows at 35–37°C with 5–10% CO2 and is susceptible to drying and temperature changes

Haemophilus spp.

Haemophilus Influenzae

• Can be isolated from: Blood, Sputum, CSF, Eye swab 

• Was a major cause of Meningitis in children, but the used of ______ vaccine has reduced it and other invasive disease caused

• Serotypes other than oreviously mentioned are frequent cause of respiratory tract infection, including:

1. Acutesinusitis

2. Chronic bronchitis

3. Pneumoniaby this serotype

Haemophilus Influenzae

• H.infuenzae type B (Hib)

• Similar to H.influenzae with the exception of it being Sucrose = POSITIVE

• Causes pinkeye, a very contagious conjunctivits

Haemophilus aegyptIus

• Resembles H.influenzae biotype III that is:

1. Indole = NEGATIVE

2. Urease = POSITIVE

3. Ornithine Decarboxylase

• Causes conjunctivitis that is followed by an invasive disease known as ______

H.influenzae biogroup aegyptius

• “Brazilian Purpuric Fever”

• Causes gentital ulcers, an STD

• Produces: Chancroids, Buboes (swollen lymph nodes)

• Chocolate Agar with vancomycin is used for the recovery as it inhibits the normal biota and contaminants

Haemophilus ducreyi 

Kingella

1. _____

• MOST clinically relevant species

• throat of children

• best isolated from joints and bones in blood culture media

2. ____

• has been isolated form the mouth of adults

3._____

• can be confused with N.gonorrhoeae

• also produce glucose and does not grow on MAC

• Nitrate reduction = POSITIVE

• forms coccobacilli instead of diplococci

1. K.kingae

2. K.oralis

3. K.denitrificans

Can be grown on:

a. SBA

b. Chocolate Agar

c. Modified Thayer- Martin Agar

d. NOT GROWN on MAC Agar

Kingella

• Gram-negative, curved bacilli

Bartonella