M17: CC3: Common Things are Common Flashcards Preview

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Flashcards in M17: CC3: Common Things are Common Deck (14)

Respiratory Tract Infections, presenting to a Family Practitioner:

We have all suffered multiple respiratory tract infections. These infections can be divided into (4).

These infections are respectively of the (4).


nasal passages


Community-acquired pneumonia:

As the name implies, community-acquired pneumonia (CAP) is pneumonia acquired _.

CAP is an extremely common cause of presentation to _, although patients with less severe CAP may not need _ admission.

Cardinal symptoms are (4).

_ is the most common cause of CAP by far.

_ and _ are other common causes of CAP.

A number of “atypical” organisms also commonly cause CAP – these include _, _, and _.

Influenza pneumonia occurs in epidemics and other viral causes are common but not often identified such as _ and _ in children.

outside of the hospital


cough productive of sputum, pleuritic chest pain, shortness of breath and fever

Streptococcus pneumoniae

Haemophilus influenzae and Moraxella catarrhalis

Chlamydophila pneumoniae, Legionella pneumophila and Mycoplasma pneumoniae

Respiratory Syncitial virus (RSV) and metapneumovirus


Hospital-acquired pneumonia:

Pneumonia may also be acquired in hospital (a _ infection).

Critically ill patients who are mechanically ventilated are particularly prone to pneumonia, a condition called _.

The most common organisms to cause VAP are (5).

Hospital-acquired organisms are frequently resistant to multiple classes of antibiotics.


ventilator-associated pneumonia (VAP)

Pseudomonas aeruginosa
Staphylococcus aureus
Acinetobacter spp.
Enterobacter cloacae
Klebsiella pneumoniae


Urinary tract infection:

Urinary tract infection (UTI) is a common complaint.

In young women, the most common etiology of cystitis (inflammation of the bladder) is _, followed by _.

Symptoms include _ (burning or stinging on passing urine) and increased _.

Patients with _ (inflammation of the kidney) have fever and flank pain, in addition to urinary tract symptoms.

Community acquired pyelonephritis is most often caused by _.

People who are incontinent of urine may require urethral _. The presence of a foreign body in the bladder provides a hospitable habitat for bacteria and other organisms – these include (4). This urinary colonization is inevitable and does not need to be treated in most cases-a change or removal of the catheter may be sufficient.

Escherichia coli
Staphylococcus saprophyticus

frequency of passage of urine

acute pyelonephritis

E. coli

E. coli, Enterococcus faecalis, Proteus mirabilis and Candida albicans


Bloodstream Infection:

The bloodstream should be a _ place. The presence of bacteria in the bloodstream (_ or _) is clearly a very serious event. Many times it results in a clinical syndrome called severe _, where basic physiologic functions are affected.

Patients with severe sepsis typically have (5).

Patients with pneumonia or pyelonephritis may become _ – the organisms causing these bloodstream infections are those that cause the underlying infection.

Patients with intravascular lines or devices may become _ because these foreign bodies serve as a ready portal for bacteria from skin to the blood.

Vascular line related bacteremia is therefore usually due to skin organisms such as _ or _.

If patients have prolonged bacteremia than an _ source is likely, the bacteria have attached to an _ (catheter or pacemaker) or _ (endocarditis). _ and _ are the most likely pathogens in this case.

bacteremia or septicemia

low blood pressure, a high heart rate, cold mottled extremities, confusion and decreased production of urine



Staphylococcus aureus or coagulase negative staphylococci

intravascular device
heart valve

Staphylococcus aureus and streptococci


Meningitis and Encephalitis:

Like the bloodstream, the _ and the _ bathing it should be a sterile place. Indeed, the brain has a series of protective barriers that prevent organisms entering it.

_ is inflammation of the brain, _ is inflammation of the meninges and _ is inflammation of both the brain and the meninges.

The most important etiologies of encephalitis are _ and _ (for example, West Nile virus).

The most important causes of meningitis are (4).

cerebrospinal fluid


herpes simplex virus and vector borne infections

Neisseria meningitidis, Streptococcus pneumonia, Listeria monocytogenes and the enteroviruses


Sexually transmitted infections:

Sexually transmitted diseases (STI’s) can be divided into those that cause _, those that cause _ and those that cause _.

The most important causes of urethritis are _ and _.

The most important causes of genital ulcers are _ and _.

Genital warts are due to _.

genital ulcers
genital warts

Chlamydia trachomatis and Neisseria gonorrhoeae

herpes simplex virus and syphilis (Treponema pallidum)

human papillomavirus



Diarrhea occurring outside of hospital is most commonly due to _ (E.coli, Salmonella, Campylobacter etc), _ (Giardia lamblia, Cryptosporidium etc) and _ (noroviruses, rotavirus, etc).

Within hospitals, _ is the most common infectious cause of diarrhea although many patients develop diarrhea as side effect of medications such as _ and _.


Clostridium difficile
laxatives and antibiotics


Cutaneous infections:

_ (inflammation of the skin) may have non-infectious etiologies such as allergic reactions or eczema.

Cutaneous infections commonly present to family practitioners. Important infectious etiologies include _ and _.

Superficial cellulitis is often caused by _ while deeper skin infections such as abscesses are most commonly caused by _.

In hospitalized patients, many systemic (generalized) infections have manifestations in the skin. Examples include (3).


dermatophytes (Tinea spp) and Candida spp

Streptococcus spp.
Staphylococcus aureus

infective endocarditis
Pseudomonas aeruginosa bacteremia
disseminated fungal infections


Infection susceptibility and Immunodeficiencies:

People are susceptible to infections when exposed to _ (legionellosis from air-conditioning units or coccidiomycosis from aerosolized desert soil), to _ (rabies after contact with bats) or to _ (influenza from a sick household member).

The breakdown of normal barriers such as skin by catheterization of blood vessels or a burn wound typically predisposes to infections with the _, although environmental contaminants (hospital, water) need to be considered as well.

The definition of an immunodeficiency is _. Immunodeficiencies can be _ or _ and put people at risk for _.

A normal host can be colonized but is rarely infected by the organisms causing OI’s who exploit some weakness in the host defense such as (4).

environmental pathogens
people with contagious diseases

resident flora of the anatomical site compromised

“a state in which the response of the host to a foreign antigen is not normal”
congenital or acquired
opportunistic infections (OI’s)

splenectomy, neutropenia, T-cell depletion (HIV, transplant), or hypogammaglobulinemia


Typical opportunistic organisms for...

Abnormalities in opsonization and reticulo-endothelial system (RES):

Complement deficiency
- Lupus (SLE)

- Liver cirrhosis, splenectomy, sickle cell disease

1) Encapsulated organisms (3)

Haemophilus influenzae
Neisseria meningitidis
Streptococcus pneumoniae


Typical opportunistic organisms for...

Granulocyte or neutrophil abnormalities:

Neutrophil dysfunction
- Chronic granulomatous disease (CGD)

Neutropenia (low number of neutrophils)

1) Catalase positive organisms (3)

Staphylococcus aureus
Pseudomonas aeruginosa


Typical opportunistic organisms for...


- IgA deficiency
- IgG deficiency
- Multiple Myeloma
- Common Variable Imm-Def. (CVID)

- Immunosuppressant medications
--> Glucocorticosteroids
--> Tumor Necrosis Factor antagonists
--> Anti-lymphocyte antibodies
--> Cytokine inhibitors (Cyclosporine)
--> Anti-metabolites (Azathioprine)

1) General
2) Encapsulated organisms
3) Fungi and yeasts
4) Parasites
5) Mycobacteria
6) Viruses

1) Giardia
Neisseria meningitidis
Haemophilus influenzae
Streptococcus pneumonia
Pneumocystis jaroveci
4) Toxoplasma
5) Tuberculosis, MAC


Respiratory Tract Infections, presenting to a Family Practitioner:

Rhinitis is almost always due to _ or _ (such as allergies) – so much so, that antibiotics can routinely be withheld from patients with a runny nose.

Most patients with “colds” have some degree of _; hence the mere presence of symptoms is not an indication for antibiotic therapy.

Some patients with sinusitis do develop bacterial infections (most commonly _), but there is no role for antibiotics during viral sinusitis in preventing bacterial sinusitis.

_ (middle ear infection) is a common infection in children – viruses are the usual etiology but _ or _ may occur.

Pharyngitis presents with a _ – this is usually due to viruses, but _ needs to be excluded in isolated pharyngitis.

Like the other respiratory infections already mentioned, acute bronchitis is usually due to viral infections. However, when it is due to bacteria, _ or _ are the most common etiologies.

Influenza is the condition, caused by Influenza A or B viruses, which presents with sudden onset of _, _, and _. Drugs are available which are active against influenza virus if used early in the disease.

viruses or to non-infectious causes


Streptococcus pneumoniae

Otitis media
Streptococcus pneumoniae or Haemophilus influenzae

sore throat
Group A Streptococcus (also called Streptococcus pyogenes)

Streptococcus pneumoniae or Haemophilus influenzae

fever, muscle aches and cough