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S. pneumoniae bleongs to the a-hemolytic group that characteristically produces a _______ color on blood agar because of the reduction of iron in hemoglobin.
greenish
Pneumococci are fastidious and grow best in _____ but require a source of _______(eg., blood) for growth on agar plates, where they develop mucoid (smooth/shiny) colonies.
5% CO2
catalase


Pneumococci w/o capsule produce colonies with rough surface.
Pneumococci, unlike other a-hemolytic streptococci, their growth is inhibited in the presence of _______ (ethylhydrocupreine hydrochloride), and they are bile soluble.
optochin
S. pneumoniae, as distinguished with rabbit polyclonal antisera; capsules swell in the presence of specific antiserum (_______ reaction).
Quellung reaction
S. pneumoniae
______1. is a secreted cytotoxin though to  result in cytolysis of cells and tissues and Lyt A enhances pathogenesis.
_____2. impedes formation of C3 converstase.
_____3. also known as choline-binding protein A (CbpA), binds factor H and is thought to  accelerate the breakdown of C3.
1. pneumolysin
2. H inhibitor (Hic)
3. pneumococcal surface protein C (PspC)

Psp A and CbpA inhibit the deposition of or degrade C3b
Pneumococcal cell surface, with key antigens and their roles

______1. secreted cytolytic/cytotoxic protein; activates complement and stimulates proinflammatory cytokines
______2. prevents complement binding; therefore antiphagocytic, target for protective antibody
______3. Interferes with complement deposition by blocking alternative complement pathway activation.
1. Pneumolysin
2. Polysaccharide capsule
3. Pneumococcal surface protein A
Pneumococcal _______ and ______1. lipoprotein components of iron ABC transporters, essential for iron uptake.
Pneumococcal ______2. principal pneumococcal adhesion molecule
________3. cleaves host extracellular matrix, aiding adhesion.
1. iron acquisition and iron uptake A
2. surface protein C (choline-binding protein A)
3. Choline-binding protein G
Pneumococcal ________1.  metal-binding lipoprotein (Zn and Mn); may have a role in adhesion
________2. degrades human IgA1
________3. degrades hyaluronan and chondrointin sulfate in extracellular matrix
1. surface antigen A
2. IgA1 protease
3. Hyaluronate lyase
Pneumococcal cell surface
_______1. Binds to platelet-activating factor receptor on human epithelial cells
_______2. Releases peptidoglycan, teichoic acid, pneumolysin, and other intracellular contents on autolysis
_______3. catalyze polymerization of glycan chains and transpeptidation of pentapeptidic moieties within structure of peptidoglycan.
1. Phosphorylcholine
2. Autolysin
3. Penicillin-binding proteins
Pneumococcal cell surface
______1. contributes to adherence; removes sialic acids on host glycopeptides and mucin to expose binding sites.
______2. Binds to fibronectin in host tissues
______3. PhtA, B, D, E: cell-surface exposed proteins, unknown function.
______4. on cell surface; inhibit phagocytosis, promote invasion
1. Neuraminidase
2. Enolase
3. Histidine triad
4. Pili
In developed-world setting, ______ serve as the major vectors of pneumococcal transmission.
Children
Pneumococci are intermittent inhabitants of the healthy human ________ and are transmitted by respiratory droplets.
nasopharynx
Invasive pneumococcal dis. (infection of a normally sterile site), rates highest among children less than __ years of age and among adults more than __ years of age.
less than 2 years of age
more than 65 years of age
Pneumonia is the most common of the serious pneumococcal disease syndrome.

Most of the pneumococcal pneumonia are not associated with ______, and in these cases a definitive etiologic diagnosis is difficult.
bacteremia
Clinical Risk groups for pneumococcal infection
1.
2.
3.
4. Chronic Kidney Disease
5. Chronic Liver Disease
6. Diabetes Mellitus
7. Immunocompromise/ Immunosuppression
8. Cochlear implants
9 Cerebrospinal fluid leaks
1. Asplenia or splenic dysfunction
2. Chronic respiratory disease
3. Chronic heart disease

Miscellaneous: Infancy and old age; prior hosp., alcoholism, cigarette smoking, day care center attendance...
Pneumoccoi can cause disease in almost any organ or part of the body; however, 
1.
2.
3.
4.
are most common.
1. otitis media
2. pneumonia
3. bacteremia
4. meningitis
The mucus itself is a component of local defense mechanisms, and the flow of mucus(driven in part by cilia in what is known as the _______ _______) effects mechanical clearance of pneumococci.
mucociliary clearance
Innate Immunity
______1. binds phosphorylcholine in the pneumococcal cell wall, inducing complement activation and leading to bacterial clearance
______2. recognizes both pneumococcal lipoteichoic acid and cell wall peptidoglycan
1. C-reactive protein (CRP)
2. Toll-like receptor 2 (TLR2)
Innate Immunity
______1. necessary for the proinflammatory effect of pneumolysin on macrophages.
______2. essential for the normal functioning of several TLRs
1. Toll-like receptor 4 (TLR 4)
2. IRAK-4 - IL-1 receptor-associated kinase 4

The gold standard for etiologic diagnosis of pneumococcal pneumonia is?
pathologic examination of lung tissue
In children, ________ a distincly spherical consolidation on chest radiography, is associated with a pneumococcal etiology.

Round pneumonia

-uncommon in adults

In cases of pneumococcal pneumonia, blood cultures are positive ____%.
less than 30%
Assay facilitated etiologic diagnosis in Adults, among whom the prevalence of pneumococcal nasopharyngeal colonization is relatively low, if it is (+), has a high predictive value?

Same is not true for children
Urinary pneumococcal antigen

Most cases of pneumococcal pneumonia are diagnosed by Gram's staining and culture of sputum.
Is the most common focal complication of pneumococcal pneumonia, occuring in less than 5% of cases?
Empyema

When fluid in pleural space is accomp. by fever and leukocytosis after 4-5 days of appropriate antibiotic treatment, empyema should be considered.
Pleural fluid with frank pus, bacteria (detected by microscopic examination) or a pH of less than ___ indicates empyema and demands aggressive and complete drainage, usually through chest tube insertion.
7.1
Now that type b vaccine is routinely used,
1.
2.are the most common bacterial causes of meningitis in both adults and children.
1. S. pneumoniae
2. Neisseria meningitidis
A definitive diagnosis of pneumococcal meningitis rests on the examination of CSF for:
1. evidence of ______ (visual inspection)
2. elevated _____ level, elevated ____ and reduced glucose concentration
3. specific identification of the etiologic agent (Culture, GS, antigen testing, PCR)
1. turbidity
2. protein level, WBC
3
Considered confirmatory for pneumococcal meningitits
1.
2.
1. blood culture (+) for S. pneumonaie
in conjunction with

2. clinical manifestations of meningitis
Mortality rate for pneumococcal meningitis is ___%.
20%
The 2 major noninvasive syndromes caused by S. pneumonaie
1.
2.
the latter is the most common pneumococcal syndrome and most often affects young children.
1. sinusitis
2. otitis media

Redness of the tympanic membrane is not sufficient for the diagnosis of otitis media.
For susceptible strains of S. pneumoniae _______ remains the most commonly used agent, with daily doses ranging from 50,000 U/kg for minor infections to 300,000 U/kg for meningitis.
Penicillin G

Macrolides and Cephalosporins are alternatives for penicillin-allergic patients.
For many years, Penicillin susceptibility breakpoints have been defined by MICs as follows:
1. Susceptible: less than _____ug/mL
2. Intermediate:  ___-__ug/mL
3. Resistant: more than ______ ug/mL
1. 0.06 ug/mL
2. 0.12-1.0 ug/mL
3. 2.0 ug/ml
As a result of increased prevalence of resistant pneumococci, first-line therapy for person more than 1 mo. of age is a:
Combination of:
________1. (adults, __-___ mg/kg/day in 6 divided doses) and
________2. (Adults, _-_ g/d in 4 to 6 divided doses)
1. Vancomycin 30-60 mg/kg/day
2. Cefotaxime 8-12 g/d
or Ceftriaxone 4 g/d in 1 dose or 2 divided doses

If hypersensitive to B-lactam
-Rifampin 600mg/d

rpt Lumbar puncture after 48 hrs
For outpatient mgt. _______ _g every _hrs. provides effective treatment for virtually all cases of pneumococcal pneumonia.
Amoxicillin 1 g every 8 hrs.
S. pneumoniae
________ __-__ mg/kg/day is recommended for children with acute otitis media except in situations where observation and symptom-based treatment without antibiotics are advocated.
Amoxicillin 80-90 mg/kg/day
PPSV 23 is effective, the duration of protection following a single dose of vaccine is estimated to be _____ years.
5 years
Near elimination of vaccine serotype nasopharyngeal colonization in immunized infants, which reduces spread to adults. This protection of unimmunized community members through vaccination of a subset of the community is termed the ______ effect.
Indirect Effect
x of y cards