General Presentation
Children frequently present at the physician’s office or emergency room with a fever and rash. Although the differential diagnosis is very broad, adequate history and physical examination can help the clinician narrow down a list of more probable etiologies. It is important for physicians to be diligent, as the differential diagnosis can include contagious infections or life-threatening diseases.
Even though there is a strong link between the presentation of fever and rash and infectious disease, it is important to keep in mind that other non-infectious diseases can also have similar presentations (e.g. drug reactions, cutaneous lupus erythematosus, inflammatory bowel disease).
Presentation
Features of the rash:
– Characteristic of lesions
– Distribution and progression
– Timing of onset in relation to fever
– Morphological changes (e.g. papules to vesicles)
Common skin lesions (see link for details)
– Macule: nonpalpable, circumscribed, flat lesion (<1 cm in diameter)
– Papule: palpable , elevated lesion (<1 cm in diameter)
– Maculopapular: combination of macular and popular lesions
– Purpura: non-blanching papules or macules due to extravasation of RBCs
– Vesicle: fluid-filled, elevated skin lesion (<1 cm in diameter)
– Bulla: fluid-filled, elevated skin lesion (>1 cm in diameter)
– Pustule: pus-containing vesicle
– Ulcer: depressed skin lesion with missing epidermis and upper layer of dermis
Questions to Ask
It is important to consider the following:
– Age of patient
– Season
– Travel history
– Geographic location
– Exposures to insects, animals, other people who are ill
– Medications
– Immunization history
– Other medical conditions
– Immune status of patient
Further questions to Ask to refine HPI:
– Was there a prodrome? (early symptoms that might indicate the start of disease)
– When did the rash start?
– Where did the rash start?
– Where has the rash spread to?
– Has there been any change in the rash (appearance, sensation, etc.)
– What has been used to treat the rash?
– Review of systems to rule out inflammatory bowel disease (diarrhea, weight loss, poor appetite, arthritis, oral ulcers, peri-rectal ulcers)
– Review of systems for lupus (photosensitivity, malar or discoid rash, cytopenias, renal disease, neurological disease, etc.)
Differential Diagnosis in a Child
Infectious
- Measles:
– Blanching erythematous maculopapular rash
– Begins in head and neck à spreads centrifugally to trunk and exrtremities
– Associated symptoms: fever, cough, coryza and conjunctivitis
2. Chickenpox:
– Vesicular lesions on erythematous base
– Lesions appear in crops
– “dew drops on rose petals” appearance
– Lesions are present in different stages: papules, vesicles, crusting
– Vesicular lesions on erythematous base
– Lesions appear in crops
– “dew drops on rose petals” appearance
– Lesions are present in different stages: papules, vesicles, crusting
3. Rubella:
– Rash resembles measles, but patient is not ill looking
– Prominent postauricular, posterior cervical +/- suboccipital adenopathy
– Forschemier spots: small, red spots (petechiae) on soft palate in 20% of rubella patients
4. Erythema infectiosum (fifth disease) – human parvovirus B19
– Characteristic rash that resembles “slapped cheeks”
5. Roseola infantum or exanthema subitum
– Human herpesvirus 6 or 7 infection
– High fever for 3-4 days
– Followed by seizures
– Generalized rash (trunk to extremities, face spared)
6. Scarlet fever
– Exotoxin-mediated diffuse erythematous rash
– Pharyngitis due to group A streptococcus
– Coarse, sandpaper-like, erythematous, blanching rash à desquamation
– Circumoral pallor and strawberry tongue
7. Non-polio enteroviruses (coxsackievirus, echovirus)
– Cause variety of different rashes
– Should be included in differential
Inflammatory
- Acute rheumatic fever
– Potential sequela of group A streptococcal pharyngitis
– Erythema marginatum – transient macular lesions with central clearing – usually found on extensor surfaces of proximal extremities and trunk
– Subcutaneous nodules over bony prominences
2. Kawasaki Vasculitis
– Usually in kids <4 years old
– Fever >5 days
– Bilateral conjunctival injection, injected or fissured lips
– Injected pharynx or “strawberry tongue”
– Erythema of palms or soles
– Edema of hands or feet
– Generalized or periungual desquamation
– Rash
– Cervical lymphadenopath
– Acute rheumatic fever
3. Systemic Lupus Erythromatosis
SOAPBRAINMD:
– Serositis (pleuritis or pericarditis)
– Oral (Ulcers)
– Arthritis (Non-erosive, any joint, polyarticular)
– Photosensitive rash
– Blood dyscrasia (anemia, leukopenia, lymphopenia or thrombocytopenia)
– Renal Nephritis
– ANA
– Immunoreactive (anti-Ds DNA, Anti-Rho, Anti-Sm, Anti-La, antiphospholipid)
– Neurological (Sz, Chorea, Psychosis)
– Malar rash
– Discoid rash
4. Inflammatory Bowel Disease
Associates with two rashes characteristically:
– Erythema Nodosum
– Pyderma Gangrenosum
Procedure for Investigation
Physical Examination
– Vital signs
– General appearance – energy level, does the child look sick?
– Lymph node, mucous membranes, conjunctivae and genitalia assessment
– Meningeal signs
– Neurologic evaluation
– Liver and spleen palpation
– Joint examination
– Skin examination
Laboratory Tests
– Complete blood count
– Urinalysis
– Blood cultures – depending on history of possible exposures
– Serologies – if indicated
– Fluid from any lesions can be examined
– Unroof vesicles so that base of lesion can be swabbed
– Skin biopsy
References
- Lopez FA, Sanders CV. Fever and rash in the immunocompetent patient. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2011
- Barinaga JL, Skolnik PR. Clinical presentation and diagnosis of measles. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2011
- Albrecht MA. Clinical features of varicella-zoster virus infection: chickenpox. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2011
- Jordan JA. Clinical manifestations and pathogenesis of human parvovirus B19 infection. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2011
Acknowledgements
Written by: Ying Yao (UBC MSI 3)
Editted by: Elmine Statham (UBC pediatrics resident)