MOD 4 QUIZLET

• Pfeiffer in 1890

  and was erroneously named during the influenza pandemic

  that ravaged the world from 1889 to 1890.

  Haemophilus influenzae was first isolated by ?
• fastidious


  special nutrients for isolation and identification, hence the term
• Factor X and/or Factor V


  Species in the genus Haemophilus require———————- for optimal growth.
• nicotinic acid


  a form of vitamin B3
• Bordetella species,


  require niacin (also known as nicotinic acid, a form of vitamin B3), cysteine, and usually methionine.
• Factor X

  Heat-stable and is frequently supplied by the incorporation of heat-lysed ("chocolatized") blood cells in agar such as in chocolate agar or Fildes medium.
• Factor y


  Nicotinamide adenine dinucleotide (NAD) or NAD phosphate

  COMMON NAME

  (NADP).
• thiamine, niacin, and biotin.

  Brucella species require ?
• General Characteristics

  •Small, pleomorphic, gram-negative bacilli. The cells are typically coccobacillary or short rods.

  • Nonmotile.

  • Facultative anaerobes.

  • Growth is enhanced in a 5% to 10% CO2-enriched atmosphere.

  • Are "blood-loving", requiring enriched media, usually containing blood or its

  derivatives, that provide preformed growth factors, X and V; isolation usually requires the presence of X and/or V factor in the culture medium.

  Haemophilus species
• Factor V

  - May also be provided by a suspension of hemolytic strains of bacteria (e.g., staphylococci, pneumococci, and neisseriae)
• Factor X


  An important component of cytochromes, catalase, and

  peroxidase
• Factor v


  Heat-labile and is commonly supplied by the incorporation of yeast extract or other appropriate supplements in the medium
• Pfeiffer's bacillus


  Haemophilus influenzae common name?
• Requires both X and V factor for growth

  Haemophilus influenzae requires?
• occurs only in humans and can be found in the upper respiratory tract (oropharynx and nasopharynx) of 20% to 80% of healthy persons.


  HABITAT of haemophilus influenzae
• transmitted from person- to-person by respiratory droplets.

  Haemophilus influenzae is trasnmittes?
• Typeable strains

  These are encapsulated strains of H. influenzae
• Nontypeable strains

  may cause mild localized infections (otitis media and sinusitis in children), and is associated with respiratory tract infections (pneumonia
• Until the availability of the Hib vaccine, H. influenzae was the most common cause of meningitis

  was the most common cause of meningitis in children between 3 months and 6 years of age when nearly all passive immunity has waned, and the child enters a vulnerable non immune period of life.
• type a, b, c, d, e, or f; all have potential to invade deeper tissues

  Typeable strains are separated into six groups which are
• H. influenzae; serotype b (Hib) strains


  90% of invasive———— infections are caused by
• Nontypeable strains


  These are most commonly encountered as normal inhabitants of the upper respiratory tract of man
• Haemophilus influenzae

  type b (Hib)

  most commonly encountered in serious infections in humans which include meningitis esp. in infants and children; and several other diseases such as epiglottitis and bacteremia.
• Nontypeable strains


  They do not produce capsule
• Meningitis

  Older children, adolescents and adults can less frequently be infected particularly those who are immunocompromised.
• Meningitis


  disease has very similar presentation with meningococcal meningitis,
• fever, malaise, occasionally vomiting, stiff neck and neurological impairment.


  Symptoms of meningitis?
• Epiglottis


  can be "cherry red" in children; "thumb sign" on lateral neck x-ray
• Meningitis

  fever, malaise, occasionally vomiting, stiff neck and neurological impairment.
• Bacteremia

  is an early

  Epiglottitis. Endoscopic appearance of epiglottis in [A] can be "cherry red" in children; "thumb sign" on lateral neck x-ray [B].

  manifestation of acute H. influenzae type b meningitis but in some infants, may occur without meningitis.
• Meningitis

  Untreated cases have high fatality (up to 90%) even with prompt diagnosis
• H. influenzae is the most common cause

  Epiglottitis most common cause
• Epiglottis

  H. influenzae is the most common

  cause of this potentially fatal disease in

  children between the ages of 2 and 4.
• Bacteremia


  It is mostly seen in children with underlying diseases (e.g., sickle cell)
• Epiglottitis

  It has a rapid onset, with sore throat, dysphagia, fever, and swollen, cherry red epiglottis above the larynx at the base of the tongue.
• airway obstruction and suffocation.

  Acute inflammation and intense edema of the epiglottis may cause complete
• Bacteremia

  fever, lethargy and high neutrophil count
• Sinusitis

  characterized by persistent cold symptoms, purulent nasal or post nasal discharge, cough, fever, headache, and often facial pain.
• Pneumonia

  characteristics are similar to pneumococcal pneumonia — lobar,

  segmental and purulent pneumonia.
• Otitis media

  Signs and symptoms include fever, irritability, headache, occasionally nausea and vomiting, ear pain, hearing loss, discharge from the ear.