A Collage of Infectious Diseases in Children

Perichondritis 

A 10-year-old girl presented with a 7-day history of severe pain in the left ear. During the past 2 days, the left auricle had become erythematous and markedly tender. The child was treated with cloxacillin, and symptoms subsided in a week.

Perichondritis presents with erythema, edema, and extreme tenderness over the affected area. Because of the lack of cartilage, the ear lobe is not affected -- unlike in cellulitis of the auricle, which generally involves the earlobe. Because the skin of the external ear is attached to the perichondrium, the severity of the pain may be disproportionate to the degree of inflammation.

Periorbital Cellulitis

A 7-year-old girl presented with a 2-day history of pain and swelling in the right periorbital area. Her temperature was 38ºC (100.4ºF). The periorbital area and the adjacent area of the face were erythematous and tender. Her vision and eye movements were normal.

The child had periorbital cellulitis. This condition can be caused by trauma, an infected wound, or sinusitis. The usual causes are Haemophilus influenzae, pneumococci, streptococci, and staphylococci. Proptosis, decreased vision, and decreased eye mobility indicate orbital extension.

Prompt antimicrobial therapy is mandatory. Oral antibiotics are acceptable if the eyelid swelling is modest and there is no evidence of toxicity. If the child appears toxic, parenteral antibiotics and hospitalization are recommended. First-line agents include amoxicillin/ potassium clavulanate, cephalexin, clarithromycin, and erythromycin/sulfisoxazole. Alternatively, a parenteral antibiotic such as cefuroxime or ceftriaxone may be given.

Bacterial Conjunctivitis

For 2 days, a 4-year-old girl had complained of discomfort and a yellow discharge from the left eye. The left conjunctiva was hyperemic, but there was no preauricular lymphadenopathy. A swab from the left eye grew Haemophilus influenzae. The child was treated with topical chloramphenicol 0.5% eyedrops and had an uneventful recovery.

Bacterial conjunctivitis in children is characterized by conjunctival hyperemia, mucopurulent discharge, and various degrees of ocular discomfort. Unlike viral conjunctivitis, the bacterial form is characterized by an absence of preauricular lymphadenopathy (except in the case of gonococcal conjunctivitis). The onset is usually acute; involvement may be unilateral or bilateral. H influenzae is the most commonly isolated organism. Others include pneumococci, staphylococci, streptococci, and Moraxella catarrhalis.

Roseola Infantum (Exanthem Subitum) 

A 10-month-old infant presented with a 3-day history of fever (39ºC to 40ºC [102.2ºF to 104ºF]). The physical examination results were essentially normal, apart from the fever. On the following day, the fever subsided and an erythematous rash erupted.

Roseola infantum is caused by human herpesvirus 6. Most cases occur during the first year of life. The illness is characterized by high fever (39ºC to 42ºC [102.2ºF to 105.8ºF]) that lasts 3 to 4 days followed by the sudden appearance of rash at defervescence (hence the term "exanthem subitum," or sudden rash). The rash usually subsides in 2 to 4 days. Roseola infantum may be complicated by febrile seizures.

There is no specific treatment. An antipyretic may be used to reduce fever and discomfort.

Tinea Corporis ("Ringworm")

This 14-year-old boy presented with an erythematous, itchy suprapubic rash of 2 weeks' duration. Microscopic examination of a potassium hydroxide wet mount preparation of skin scrapings showed yeast hyphae. The boy was treated with topical terbinafine and the lesions resolved.

Tinea corporis is a superficial fungal infection of the nonhairy (glabrous) skin, excluding the groin, palms, and soles. The major causes include Trichophyton tonsurans, Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum canis, and Epidermophyton floccosum. The most characteristic lesion is an annular, scaly plaque that has a papular border and some degree of central clearing (hence the name "ringworm"). Pruritus is common. Lesions may vary in size from a few millimeters to several centimeters and may be solitary or multiple. The condition can be acquired by direct contact with infected persons or by autoinoculation.