STREPTOCOCCUS PNEUMONIAE
STRESS AND HEART RATE
The graph shows how a person’s heart rate varies over a typical day. Exercise and
stress both activate the body’s “fight-or-flight” system and increase heart rate,
but repeated alerting of the system without accompanying physical activity is
probably harmful. Although the home and workplace both present stress, for many
city workers the most stressful parts of the day are those spent commuting.
C e r t a i n t y p e s o f s t r e p t o c o c c i a r e p r e s e n t
h a r m l e s s l y i n t h e m o u t h a n d t h r o a t o f
m o s t p e o p l e .
I f t h e
b a c t e r i a e n t e r t h e
b l o o d s t r e a m
( w h i c h
m a y
h a p p e n
a f t e r
d e n t a l t r e a t m e n t ) ,
t h e y
a r e
u s u a l l y
d e -
s t r o y e d . H o w e v e r , i n s o m e p e o p l e w i t h
h e a r t - v a l v e d e f e c t s , b a c t e r i a c a n s e t t l e i n
t h e h e a r t t o c a u s e b a c t e r i a l
endocarditis
.
A n o t h e r
t y p e
o f
s t r e p t o c o c c u s
i s
n o r m a l l y
p r e s e n t
h a r m l e s s l y
i n
t h e
i n t e s t i n e s b u t c a n s p r e a d t o c a u s e a
uri-
nary tract infection
.
H a e m o l y t i c
s t r e p t o c o c c i
c a n
c a u s e
tonsillitis
, strep throat, scarlet fever, otitis
media
( m i d d l e - e a r
i n f e c t i o n ) ,
pneumo-
nia
, erysipelas,
a n d w o u n d i n f e c t i o n s .
Streptococcus pneumoniae
A l s o
c a l l e d
P n e u m o c o c c u s ,
a
t y p e
o f
S t r e p t o c o c c u s
b a c t e r i u m
t h a t
c a n
c a u s e
p n e u m o n i a a n d o t h e r s e r i o u s d i s o r d e r s
s u c h a s
meningitis
a n d
septicaemia
.
s tre p to k in a s e
A
thrombolytic drug
t h a t i s u s e d t o d i s -
s o l v e b l o o d c l o t s f o l l o w i n g a
myocardial
infarction
( h e a r t
a t t a c k )
o r
pulmonary
embolism
( a c l o t w h i c h b l o c k s a b l o o d
v e s s e l i n a l u n g ) . S t r e p t o k i n a s e i s g i v e n
u n d e r
s t r i c t
s u p e r v i s i o n
d u e
t o
t h e
s i d e e f f e c t o f e x c e s s i v e b l e e d i n g ;
o t h e r
a d v e r s e e f f e c t s i n c l u d e n a u s e a , r a s h , a n d
c a r d i a c
arrhythmias
.
s tre p to m y c in
A n
antibiotic drug
t h a t i s
u s e d t o t r e a t
c e r t a i n u n c o m
m o n i n f e c t i o n s , i n c l u d i n g
tuberculosis
,
tularaemia, plague,
a n d
bru-
cellosis
.
I t
m a y
d a m a g e
n e r v e s
i n
t h e
i n n e r e a r , d i s t u r b i n g b a l a n c e a n d c a u s -
i n g
d i z z i n e s s ,
tinnitus
( n o i s e s
i n
t h e
e a r s ) ,
o r
d e a f n e s s .
O t h e r
s i d e
e f f e c t s
i n c l u d e f a c i a l n u m b n e s s , t i n g l i n g i n t h e
h a n d s , a n d h e a d a c h e .
s t re s s
A n y
d i s t u r b a n c e
o f a p e r s o n ’s
m e n t a l
a n d p h y s i c a l w e l l b e i n g .
S t r e s s m a y b e
f e l t i n r e s p o n s e t o a r a n g e o f p h y s i c a l
a n d e m o t i o n a l s t i m u l i . I n s t r e s s f u l s i t u a -
t i o n s , t h e b o d y r e s p o n d s b y i n c r e a s i n g
p r o d u c t i o n o f t h e h o r m o n e s
adrenaline
( e p i n e p h r i n e ) a n d
hydrocortisone
,
w h i c h
p r o d u c e
c h a n g e s
i n
h e a r t
r a t e ,
b l o o d
p r e s s u r e ,
a n d
m e t a b o l i s m
t o
i m p r o v e
p e r f o r m a n c e .
A b o v e
a
c e r t a i n
l e v e l ,
h o w e v e r , t h e y i m p a i r a p e r s o n ’s a b i l i t y
t o
c o p e .
C o n t i n u e d e x p o s u r e t o s t r e s s
o f t e n
l e a d s
t o
m e n t a l
a n d
p h y s -
i c a l s y m p t o m s s u c h a s
anxiety
a n d
de-
pression
,
indigestion
,
p a l p i t a t i o n s ,
a n d
m u s c u l a r a c h e s a n d p a i n s .
Post-traumatic
stress disorder
i s a s e v e r e r e s p o n s e t o a
s p e c i f i c s t r e s s f u l e v e n t .
( S e e a l s o
relax-
ation techniques; stress ulcer
.)
s t r e s s fra c tu re
A
fracture
t h a t r e s u l t s f r o m r e p e t i t i v e j a r -
r i n g
o f a b o n e .
C o m m o n s i t e s i n c l u d e
t h e
m e t a t a r s a l b o n e s
i n
t h e
f o o t
( s e e
march fracture
) ,
t h e
tibia
a n d
fibula
( l o w e r
l e g b o n e s ) , t h e n e c k o f t h e
femur
( t h i g h
b o n e ) ,
a n d
t h e
l u m b a r
s p i n e
( l o w e r
b a c k ) . T h e m a i n s y m p t o m s a r e p a i n a n d
t e n d e r n e s s a t t h e f r a c t u r e s i t e . D i a g n o s i s
i s b y
bone
imaging
. T r e a t m e n t c o n s i s t s o f
r e s t i n g t h e a f f e c t e d a r e a f o r f o u r t o s i x
w e e k s , d e p e n d i n g o n t h e s i t e ; t h e f r a c -
t u r e m a y b e i m
m
o b i l i z e d i n a
cast
.
s t r e s s u lc e r
A n a c u t e
( o f s u d d e n o n s e t )
peptic ulcer
t h a t d e v e l o p s a f t e r
shock
,
a s e v e r e b u r n
o r i n j u r y , o r d u r i n g m
a j o r i l l n e s s . S t r e s s
u l c e r s
a r e
u s u a l l y
m u l t i p l e
a n d
m o s t
c o m
m o n l y
o c c u r i n t h e
s t o m a c h . T h e
e x a c t
c a u s e
i s
u n k n o w n .
S e v e r e l y
i l l
h o s p i t a l p a t i e n t s a r e o f t e n g i v e n d r u g s
t o p r e v e n t s t r e s s u l c e r s f r o m d e v e l o p i n g .
s tre tc h e r
A h o r i z o n t a l f r a m e u s e d t o c a r r y s e r i -
o u s l y i l l o r i n j u r e d p e o p l e . T h e s t r e t c h e r
k e e p s t h e p e r s o n ’s b o d y f l a t a n d s t i l l ,
m
i n i m i z i n g t h e r i s k o f f u r t h e r i n j u r y o r
d i s t u r b a n c e t o t h e b o d y
s tre tc h -m a rk
S e e
stria
.
s tria
A l s o
c a l l e d
a s t r e t c h - m a r k ,
a
l i n e
o n
t h e
skin
c a u s e d b y t h i n n i n g a n d l o s s o f
e l a s t i c i t y i n t h e d e r m i s . S t r i a e a p p e a r a s
r e d ,
r a i s e d l i n e s ,
b e f o r e t u r n i n g
p u r -
p l e ; t h e y e v e n t u a l l y f a d e t o f o r m
s h i n y ,
s i l v e r y s t r e a k s .
S t r i a e o f t e n d e v e l o p , d u r i n g t h e a d o -
l e s c e n t g r o w t h s p u r t , o n t h e s h o u l d e r s
i n b o y s a n d o n t h e h i p s a n d t h i g h s i n
a t h l e t i c g i r l s . T h e y a r e a c o m
m o n f e a -
t u r e
o f p r e g n a n c y ,
o c c u r r i n g
o n
t h e
b r e a s t s ,
t h i g h s ,
a n d
l o w e r
a b d o m e n .
P u r p l e s t r i a e a r e a c h a r a c t e r i s t i c f e a t u r e
o f
Cushing’s syndrome.
T h e m a r k s a r e t h o u g h t t o b e c a u s e d
b y a n e x c e s s o f
corticosteroid hormones,
w h i c h
d e c r e a s e s
t h e
l e v e l
o f
collagen
( f i b r o u s t i s s u e ) i n t h e s k i n . T h e r e i s n o
m e a n s o f p r e v e n t i o n , b u t i n s o m e c a s e s
l a s e r t r e a t m e n t m a y b e u s e d .
K
Striae
Commonly known as stretch-marks, striae often
develop on the abdomen, thighs, and breasts of
pregnant women. The striae shown here result from
obesity associated with
C u s h i n g ' s s y n d r o m e .
716
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