Transcript Cardinal Manifestations of Disease: ALTERATIONS

Cardinal Manifestations of Disease:
ALTERATIONS IN BODY TEMP.
Dr. Gerrard Dennis Uy
Fever and Hyperthermia
• hypothalamic thermoregulatory center –
regulates body temperature (core BT 37 C)
• A.M. temperature of >37.2°C (>98.9°F) or a
P.M. temperature of >37.7°C (>99.9°F) would
define a fever
• Rectal temperatures are
generally 0.4°C (0.7°F) higher
than oral readings
Fever
• Elevation of body temperature that
exceeds the normal daily variation
• occurs in conjunction with an increase in
the hypothalamic set point
• Vasoconstriction in hands and feet shunts
blood to the internal orgrans
• shivering = heat conversion and
production
• until the temperature of the blood
bathing the hypothalamic neurons
matches the new thermostat setting
Fever
• Pathogenesis
– Pyrogen – any substance that causes fever
• Exogenous (microbial products, microbial toxins, or
whole microorganisms)
– E.g. LPS endotoxin – gram negative bacteria
• Endogenous a.k.a Pyrogenic cytokines (IL-1, IL-6, tumor
necrosis factor (TNF), ciliary neurotropic factor (CNTF),
and interferon (IFN) )
– Elevation of Hypothalamic Set point
• levels of prostaglandin E2 (PGE2) are elevated in
hypothalamic tissue and the third cerebral ventricle
Hyperthermia
• uncontrolled increase in body temperature
that exceeds the body's ability to lose heat
• setting of the hypothalamic thermoregulatory
center is unchanged
• does not involve pyrogenic molecules
• Exogenous heat exposure and endogenous
heat production
Hyperthermia
• Can be rapidly fatal
• Does not respond to antipyretics
The Decision to Treat Fever
• Most fevers are associated with self limiting
infections
• There is no significant clinical evidence that
antipyretics delay the resolution of viral or
bacterial infections nor there is evidence that
fever facilitates recovery from infection
• Fever can provide important diagnostic clues
in different disease conditions
The Decision to Treat Fever
• The objective in treating fever is to reduce the
elevated set point and to facilitate heat loss
• Reducing fever also reduces systemic
symptoms
• Treatment of fever in some patients is highly
recommended (cadiac, cerebrovascular, and
pulmonary diseases)
Mechanism of antipyretics
• Acts by reducing the level of PGE2
• Common antipyretics
– Acetaminophen
– Aspirin
– NSAIDS
– glucocorticoids
FEVER and RASH
Approach to the patient with fever and
rash
• A thorough history if often needed
• Includes:
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Immune status
Medications taken within the previous month
Travel history
Immunzation status
Exposure to domestic pets
Recent exposure to ill individuals
• The history should also include onset and
direction and rate of spread
Types of lesions
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Macules - flat lesions defined by an area of changed color
Papules - raised, solid lesions <5 mm in diameter
plaques ->5 mm in diameter with a flat, plateau-like surface
nodules ->5 mm in diameter with a rounded configuration
Wheals (urticaria, hives) - papules or plaques that are pale
pink and may appear annular (ringlike) as they enlarge
• Vesicles (<5 mm) and bullae (>5 mm) are circumscribed,
elevated lesions containing fluid
• Pustules are raised lesions containing purulent exudate
Types of lesions
• Nonpalpable purpura: - flat lesion that is due
to bleeding into the skin.
– <3 mm --- petechiae
– >3 mm --- ecchymoses
MACULES
PAPULES
PLAQUES
NODULES
PUSTULES
WHEALS
VESICLES
BULLA
PETECHIAE
ECCHYMOSES
RUBEOLA
• Also known as measles/first dse
• Caused by paramyxovirus
• rash starts at the hairline 2–3 days into the
illness and moves down the body, sparing the
palms and soles
• Associated with cough, conjunctivitis, coryza,
and severe prostration
• Koplik's spots - seen during the first 2 days
RUBEOLA
• Infection is spread by contact with droplets
from the nose, mouth, or throat of an infected
person
• Sneezing and coughing can put contaminated
droplets into the air.
• Resolves spontaneously after 1-2 weeks
RUBELLA
• also known as German measles/3rd disease or
3 day measles
• Caused by togavirus
• also spreads from the hairline downward, but
tend to clear from originally affected areas as
it migrates, and it may be pruritic
• Usually accompanied by postauricular,
suboccipital and posterior cervical
lymphadenopathy
RUBELLA
• Forschheimer spots – red spots (petechiae)
seen on the soft palate in 20% of patients
– Not diagnostic of rubella
ERYTHEMA INFECTIOSUM
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also known as the fifth disease
Caused by human parvovirus B19
primarily affects children 3–12 years old
develops after fever has resolved as a bright
blanchable erythema on the cheeks (slapped
cheek appearance)
– more diffuse rash (often pruritic) appears the next day
on the trunk and extremities and then rapidly
develops into a lacy reticular eruption that may wax
and wane over 3 weeks
ERYTHEMA INFECTIOSUM
• Only supportive treatment
• No known complications
SLE
• typically develop a sharply defined,
erythematous eruption in a butterfly
distribution on the cheeks (malar rash)
• Etiology is autoimmune
Still’s Disease
• Juvenile rheumatoid arthritis
• manifests as an evanescent salmon-colored
rash on the trunk and proximal extremities
that coincides with fever spikes
• Etiology unknown
Fever of Unknown Origin (FUO)
Classic Definition
• 1) temperatures of >38.3°C (>101°F) on
several occasions
• (2) a duration of fever of >3 weeks
• (3) failure to reach a diagnosis despite 1 week
of inpatient investigation
Fever of Unknown Origin
New Classification
• (1) classic FUO
• (2) nosocomial FUO
• (3) neutropenic FUO
• (4) FUO associated with HIV infection
Classic FUO
• temperatures of >38.3°C on several occasions
• a duration of fever of >3 weeks
• 3 outpatient visits or 3 days in the hospital
without elucidation of a cause or 1 week of
"intelligent and invasive" ambulatory
investigation
• CAUSES:
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Undiagnosed – 30%
Infections (e.g. Tuberculosis) – 26%
Non-infectious Inflammatory (e.g.PR, SLE)– 24%
Neoplasms – 12.5%
FUO
• Nosocomial FUO – more than 50% are
infected
– Intravascular lines, septic phlebitis, and prostheses
are all suspect
– Multiple blood, wound, and fluid cultures are
mandatory
– Threshold for CT scans, ultrasonography, 111In
WBC scans, noninvasive venous studies is low
FUO
• Neutropenic FUO - neutrophil coun < 500/ul
– Neutropenic patients are susceptible to focal
bacterial and fungal infections, to bacteremic
infections, to infections involving catheters
(including septic thrombophlebitis), and to
perianal infections
– Candida and Aspergillus infections are common
– 50–60% of febrile neutropenic patients are
infected, and 20% are bacteremic
FUO
• HIV- associate FUO
– Due to HIV alone
– due to Mycobacterium avium or Mycobacterium
intracellulare, tuberculosis, toxoplasmosis, CMV
infection, Pneumocystis infection, salmonellosis,
cryptococcosis, histoplasmosis, non-Hodgkin's
lymphoma, and (of particular importance) drug
fever
Hypothermia and Frostbite
• Accidental hypothermia - unintentional drop
in the body's core temperature below 35°C
• Primary accidental hypothermia is a result of
the direct exposure of a previously healthy
individual to the cold
• Secondary hypothermia is a result from
complication of a serious disorder
Hypothermia
• Causes:
– Climate
– Endocrine dysfunction
– Adrenal insufficiency
– Hypopituitarism
– Neurologic injury
– sepsis
Hypothermia
• Heat loss occurs through five mechanisms:
– radiation (55–65% of heat loss)
– conduction (10–15% of heat loss, but much
greater in cold water)
– convection (increased in the wind)
– Respiration
– evaporation (which are affected by the ambient
temperature and the relative humidity)
Hypothermia
• Hypothermia is confirmed by measuring the core
temperature, preferably at two sites.
– Rectal probes should be placed to a depth of 15 cm
– Simultaneous esophageal probe placed 24 cm below
the larynx
• cardiac monitoring should be instituted, along
with attempts to limit further heat loss
• Supplemental oxygenation is always warranted
• NGT, FBC
• Establish IV line with warm saline
BACK AND NECK PAIN
Anatomy Review
• Anterior portion of the spine consist of
cylindrical vertebral bodies separated by
intervertebral disks
• The disks are responsible for 25% of spinal
column strength
• The function of the anterior spine is to absorb
shock of body movements
Anatomy Review
• The posterior portion of the spine consists of
the vertebral arches and seven processes
• The function of the posterior spine is to
protect and spinal cord and nerves and to
stabilize the spine by providing sites for
attachments of muscles and ligaments
• Nerve root injury (radiculopathy) is a common
cause of neck, arm, and low back and leg pain
• Pain sensitive structures in the spine:
– Periosteum of the vertebra
– Dura
– Facet joints
– Annulus fibrosus
– Epidural veins
– Posterior longitudinal ligaments
Types of back pain
• Local Pain
– Caused by stretching of pain sensitive structures
that compress or irritate sensory nerve endings
• Pain referred to the back
– May arise from abdominal or pelvic viscera
– Usually unaffected by posture
– Nonspecific back pains
Types of back pain
• Pain of spine origin
– Diseases affecting the upper lumbar spine tend to
refer pain to the lumbar region, groin, or anterior
thighs
– Diseases affecting the lower lumbar spine tend to
refer pain to the buttocks, posterior thighs, calves
• Radicular back pain
– Sharp and radiates from the lumbar spine to the leg
– Pain may increase in postures that stretch the nerves
and nerve roots
Examination of the back
• Straight leg – raising test (SLR test):
– Also called lasegue test
– to determine whether a patient with low back
pain has an underlyingherniated disk, mostly
located at L5
– With the patient lying flat, passive flexion of the
extended leg at the hip stretches the L5 and S1
nerve roots and the sciatic nerve
– Positive if the maneuver reproduces the usual
back or limb pain
Examination of the back
• Crossed SLR sign
– Less sensitive but more specific for disk herniation
– Positive when flexion of one leg reproduces the
pain in the opposite leg or buttocks
• Reverse SLR sign
– Elicited by standing the patient next to the
examination table and passively extending each
leg with the knee fully extended
– Positive if the patient’s usual back or limb pain is
reproduced
Common Causes of Back Pain
• Congenital Anomalies:
– Spondylosis:
• A bony defect of the vertebra
• Usually bilateral
• Most common cause of persistent low back pain in
adolescents
• Often activity related
– Spondylolisthesis:
• Anterior slippage of the vertebral body, pedicles, and
superior articular facets, leaving the posterior elements
behind
• Occurs more frequently in women
• Congenital Anomalies cont
– Spina bifida
• Failure of closure of one or several vertebral arches
posteriorly
• The meninges and spinal cord are normal
– Tethered cord syndrome
• Usually presents as a progressive cauda equina disorder
• Patient is often a young adult who complains of
perineal or perianal pain
Common Causes of Back Pain
• Trauma
– Patients may have a spinal fracture or dislocation
• Sprains and Strains
– Usually minor self limiting injuries associated with
lifting a heavy object, a fall, or a sudden
deceleration
– Pain is usually confined to the lower back
– No radiation present
Common Causes of Back Pain
• Lumbar Disk Disease
– Most likely to occur at the L4-L5 and L5-S1 levels
– Cause is unknown
– Risk is increased in overweight individuals
– Degeneration of the nucleus pulposus and
annulus fibrosus increases with age
– Pain is usually located in the low back and maybe
referred to the leg, buttock, or hip
Neck
• Neck pain usually arises from diseases of the
cervical spine and soft tissues of the neck
• Causes of neck pain:
– Trauma
– Cervical Disk Disease
– Cervical Spondylosis
Cervical Disk Disease
• Presents with neck pain, stiffness, and limited
range of motion
• Spurling’s Sign – extension and lateral rotation
of the neck reproduces symptoms
• Cervical disk herniations are usually
posterolateral
• For the next meeting, read on Cardinal
Manifestations of Disease : DYSPNEA
• Harrison’s Principles of Internal Medicine 17th
edition