Johns Hopkins CF Center | What is CF? | Basic Science | Lung Problems

Johns Hopkins CF Center

Overview
Basic Science
   - CFTR
        - Structure
       - Function
       - Cellular Processing
       - Mutations
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       - Bacteria/Infection
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        - Lung Damage
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     Problems
        - What Enzymes Do
        - Malabsorption
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Effects of CF
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Ask the Experts

Although the reason for frequent infection is unclear, two aspects of CF offer clues:

• The mucus within the ASL is thick and not easily cleared from the lung, trapping bacteria.

• The mucus itself is a good source of nutrients for the bacteria to survive.

What?	The bacteria Staphylococcus aureus that causes skin infections and pneumonia.
Where?	Commonly carried on the skin and in the nose.
Treatment?	Once easily treated by antibiotics, a methicillin-resistant strain known as MRSA is becoming more common.

What?	The bacteria Pseudomonas aeruginosa, the principle bacteria responsible for lung injury in CF patients.
Where?	Commonly found in soil, water and salad bars.
Treatment?	P. aeruginosa can be treated with oral, inhaled or intravenous antibiotics. Once easily treated by several types of antibiotics, multiple-drug resistant strains known as MDR-Pa are becoming increasingly prevalent and much more difficult to treat.
Quick Fact?	Forms large colonies, known as biofilms, which help it avoid consumption by neutrophils. One form of P. aeruginosa produces large amounts of a sugar (alginate) matrix and adheres to the damaged epithelial cell surfaces making the organism virtually impossible to eradicate. This type of P. aeruginosa is described as “mucoid”.

Both Pseudomonas aeruginosa and Staphylococcus aureus have enhanced ability to bind to the CF airway epithelium because of the altered CF mucus.

What?	The bacteria family Burkholderia cepacia, a complex family of bacteria that cause a chronic bacterial infection of the lungs associated with a more rapid decline in lung function.
Where?	B. cepacia can live on moist surfaces for a week and in water for years.
Treatment?	A tough bacteria to treat as it is resistant to most antibiotics.
Quick Fact?	There are nine family members that have slightly different DNA (called a genomovar) and have different names, for example B. multivorans and B. cinocepacia.

The fungus Aspergillus fumigatus may also live in the lungs of both children and adults. This infection typically does not cause problems unless patients develop and allergy to the Aspergillus fumigatus called allergic bronchopulmonary aspergillosis or ABPA.

Select from the menu above to compare the normal lung airway to the lung airway with CF and bacterial infection or with CF and inflammation.