FEVER AND RASH Flashcards
_________: 4 serotypes
•Carried by Aedes aegypti
•
•Dengue virus
____________ is usually associated with secondary dengue infections
Dengue hemorrhagic fever
- Etilogy: RNA virus (Paramyxoviridae Family)
- Mode of Transmission: by droplet spray during the prodromal period
- Period of communicability: 4 days before & 4 days after the onset of the rash
RUBEOLA (MEASLES)
Pathognomonic Sign:
•Koplik spots
Øgrayish white dots with red border opposite the lower molars
Øappear before the prodrome
RUBEOLA/ MEASLES
WHAT ARE THE 3C’s prodrome in rubeola/ measles?
•prodrome: high-grade fever + 3 C’s (conjunctivitis, cough, coryza) for 3-5 days
- @ height of fever: maculopapular rash appears on the hairline or face and spreads cephalocaudally
- Rash fades downward à branny desquamation and disappears within 7-10 days
RUBEOLA/ MEASLES
•Vitamin A:
–single dose
–100,000 IU orally for 6 mo-1 yr
–200,000 IU for > 1 yr old
–Especially indicated for hospitalized patients & with complications (ophthalmologic evidence of vitamin A deficiency & malnourished patients)
Rubeola/ measles
Measles: Complications
- Otitis media
- Pneumonia
- Encephalitis (Subacute sclerosing panencephalitis)
- Caused by: altered measles virus harbored intracellularly in CNS
- Occurs 7-10 years post measles infection
Subacute sclerosing panencephalitis
(SSPE)
What happens in the stage 1 of SSPE?
- Stage 1
- Subtle changes in behavior & deterioration of schoolwork, decreased attention span, temper outbursts
What happens in the stage 2 of SSPE?
- Stage 2
- Massive, repetitive myoclonic jerks esp. of the axial muscles
What happense in the stage 3 of SSPE?
- Stage 3
- Choreo-athetosis, rigidity, dystonia, decreased sensorium, dementia, stupor, coma
What happens in stage 4 of SSPE?
- Stage 4
- loss of central control for breathing, heart rate, blood pressure
- è death
- Due to RNA virus of Togaviridae family
- Spread by oral droplet or transplacentally to the fetus
- Period of highest communicability: 5 days before & 6 days after the onset of the rash
German Measles/ Rubella
•Forchheimer spots
Ødiscrete rose spots on the soft palate
Øjust before the onset of rash
20% of patients
Rubella: Clinical Manifestations
The Rash
- can be the first symptom to appear
- maculopapular rash begins on the face and spreads quickly cephalocaudally
- Duration: 3 days
- w/o desquamation
•low grade fever for 1-3 days
•retroauricular, posterior cervical & suboccipital lymphadenopathy (begins 24 hrs before the rash and remains for 1 week)
•Polyarthritis esp.in older girls
RUBELLA
RNA virus
(Togaviridae Family→ replicates in the respiratory epithelium
•spreads to regional lymph nodes→spreads to regional lymph nodes
RUBELLA
Risk for congenital defects & disease is greatest with primary maternal infection during the 1st trimester
Congenital Rubella
- Intrauterine growth retardation
- Congenital cataracts
- Microcephaly
- Structural heart defects like PDA
- “blueberry muffin” skin lesions
- Sensorineural Hearing Loss
- Motor and mental retardation
Congenital Rubella
- Human herpesvirus type 6
- Aka Exanthem Subitum, Sixth disease
ROSEOLA
•High grade fever for 3-5 days
•Rash appears coincident with resolution of fever
•Rash: small, evanescent morbilliform, blanching, pink (rose-colored) rash
•Appears on trunk è to face & extremities
lasts for 1-3 days
ROSEOLA
•Nagayama spots: ulcers at uvulopalatoglossal junction
•Mild injection of pharynx, palpebral conjunctivae, or tympanic membranes
•Enlarged suboccipital nodes
•
Pathophysiology: Unknown
ROSEOLA
- _____________is a neurotropic human herpes virus
- Chickenpox: primary infection
•Period of communicability: 1-2 days before the rash until all lesions have crusted
Varicella zoster virus
•_________ activation of latent sensory ganglion neurons
Herpes Zoster (shingles):
- The Rash
- Trunk àother parts of the body
- Macule/papuleà vesicleà crust
- In various stages are of evolution
Varicella
Pathogenesis:
Human herpes virus
- Inoculates in mucosa of the upper respiratory tract and tonsilar lymphoid tissue
- spreads to reticuloendothelial system
- Viremia è Cutaneous lesions
Varicella
- The Rash
- same as varicella with severe pain & tenderness along the posterior nerve roots
Herpes Zoster
- The Rash
- same as varicella with severe pain & tenderness along the posterior nerve roots
herpes zoster
Human herpes virus
- Transported via sensory axons to the dorsal root ganglia (during 10 infection)
- Latent infection in neurons and satellite cells
- reactivatiionè rash within dermatomal distribution
Herpes Zoster
What are the secondary complications of Varicella?
- secondary bacterial infection
- encephalitis or meningitis
- Pneumonia
- glomerular nephritis
- Fetuses infected at 6-12 wks of gestation have maximal interruption of limb development à short & malformed limbs covered with cicatrix – skin lesion with zigzag scarring
- Fetuses infected at 16-20 wks of gestation - eye & brain involvement
Congenital Varicella
- Most common cause: Coxsackievirus A16
- Enterovirus 71: more severe
HAND, FOOT & MOUTH DISEASE (HFMD
The Rash
ØTender maculopapular, Ulcerative intraoral lesions on tongue & buccal mucosa
Øvescicular, pustular lesions on hands & feet
HFMD
What are the complications of HFMD
•Complication: myocarditis, pericarditis, shock
- parvovirus B19
- Common in 5-15 years old
- Transmission: large droplet spread & blood transfusion
ERYTHEMA INFECTIOSUM