Browsed by
Tag: pneumoniae

Dear Dr. K; 

Dear Dr. K; 

I just turned 65 and I want to get a pneumonia vaccine, but quite honestly, I’m confused by the choices.   

The confusion is not unique to you.  There has been a longitudinal/temporal change/improvement in the vaccine.   To cut to the chase the CDC Advisory Committee on Immunization Practices recommends you (as previously unvaccinated) receive PCV21 followed a year later by PPSV23.   

By way of explanation, PPSV stands for pneumococcal polysaccharide vaccine.  It is the original vaccine and is similar in formulation to the tetanus vaccine.  PCV stands for pneumococcal conjugate vaccine.  In this format the polysaccharide antigens are conjugated to a diphtheria protein to elicit a more robust immune response.  With the learning curve of time, scientists have found using both formats leads to the best and most durable immune response.   

The earliest conjugate vaccine was PCV13 (protecting against 13 of the most common pneumonia types).  Over time PCV15, PCV20 and then PCV21 have come along.  PCV21 includes 8 serotypes not included in any of the other vaccines.  Hence, the CDC’s current advice. 

Tiniest cells causing big misery in young and old

Tiniest cells causing big misery in young and old

An infection that previously was mostly seen in children, over the past 15 years has been showing up more frequently in older adults. With its extended incubation period (2-4 weeks), it is difficult to diagnose, and capable of emerging as bronchitis or pneumonia.

And it is caused by the smallest free-living organisms — Mycoplasma pneumoniae — that were originally thought to be viruses, but have been shown to be bacteria. Unlike most bacteria they lack a cell wall and are bounded by only a thin plasma membrane.

These unique properties extend to their clinical features. Hence, the individual patient can have an extended period of “feeling like they are getting sick, but not really being sure.” Then the steamroller hits, often presenting as bronchitis or pneumonia, along with symptoms in other areas: headache, muscle aches, arthritis and GI symptoms. It can also cause a very painful type of ear infection with blisters on the ear drum.

Because of its lack of a cell wall it’s very difficult to grow in a culture and can be “missed” by this test; a fairly accurate blood test exists. It may be best recognized by its slow onset with attendant non-respiratory symptoms. It does respond to a few specific antibiotics: tetracyclines, macrolides and fluoroquinolones.