Approach to the Child with a fever and rash

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

1. 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

1. 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

1. Lopez FA, Sanders CV. Fever and rash in the immunocompetent patient. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2011
2. Barinaga JL, Skolnik PR. Clinical presentation and diagnosis of measles. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2011
3. Albrecht MA. Clinical features of varicella-zoster virus infection: chickenpox. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2011
4. 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)