Pustular rash
A pustular rash is made up of crops of pustules — visible collections of pus within or beneath the epidermis, commonly in a hair follicle or sweat pore. These lesions vary greatly in size and shape and can be generalized or localized to the hair follicles or sweat glands. (See Recognizing common skin lesions, pages 488 and 489.) Pustules can result from a skin or systemic disorder, the use of certain drugs, or exposure to a skin irritant. Although many pustular lesions are sterile, a pustular rash usually indicates infection. Any vesicular eruption, or even acute contact dermatitis, can become pustular if secondary infection occurs.
History
Have the patient describe the appearance, location, and onset of the first pustular lesion. Did another type of skin lesion precede the pustule? Find out how the lesions spread. Ask what medications the patient takes and if he has applied any topical medication to his rash. If so, what type and when did he last apply it? Find out if he has a family history of a skin disorder.
Physical assessment
Assess the entire skin surface, noting if it’s dry, oily, moist, or greasy. Record the exact location and distribution of the skin lesions and their color, shape, and size.
Medical causes
Acne vulgaris
Pustules typify inflammatory lesions of acne vulgaris and are accompanied by papules, nodules, cysts, open comedones (blackheads) and closed comedones (whiteheads). Lesions commonly appear on the face, shoulders, back, and chest. Other findings include pain on pressure, pruritus, and burning. Chronic recurrent lesions produce scars.
Blastomycosis
Blastomycosis, a fungal infection, produces small, painless, nonpruritic macules or papules that can enlarge to well-circumscribed, verrucous, crusted, or ulcerated lesions edged by pustules. Localized infection may cause only one lesion; systemic infection may cause many lesions on the hands, feet, face, and wrists. Blastomycosis also produces signs of pulmonary infection, such as pleuritic chest pain and a dry, hacking or productive cough with occasional hemoptysis.
CULTURAL CUE:Blastomycosis is generally found in North America (where the fungus Blastomyces dermatitidis inhabits the soil) and is endemic to the southeastern United States. Sporadic cases have also been reported in Africa.
Folliculitis
This bacterial infection of hair follicles produces individual pustules, each pierced by a hair and possibly accompanied by pruritus. Folliculitis might progress to the hard painful nodules of furunculosis. “Hot tub” folliculitis produces pustules on areas covered by a bathing suit.
Furunculosis
A furuncle is an acute, deep-seated, red, hot, tender abscess that evolves from a staphylococcus folliculitis. Furuncles usually begin as small, tender red pustules at the base of hair follicles. They’re likely to occur on the face, neck, forearm, groin, axillae, buttocks, and legs — areas that are prone to repeated friction. The pustules usually remain tense for 2 to 4 days and then become fluctuant. Rupture discharges pus and necrotic material. Then pain subsides, but erythema and edema may persist.
Gonococcemia
Gonococcemia produces a rash of scanty, pinpoint erythematous macules that rapidly become vesiculopustular, maculopapular and, frequently, hemorrhagic. Bullae may form. Mature lesions are elevated, with dirty gray necrotic centers and surrounding erythema. The rash appears on the distal part of the arms and legs, usually during the 1st day that other findings, such as fever and joint pain, occur. The rash disappears after 3 to 4 days but may recur with each episode of fever.
Impetigo contagiosa
Impetigo contagiosa is a vesiculopustular eruptive disorder, which occurs in nonbullous and bullous forms, that’s usually caused by streptococci or staphylococci. Vesicles form and break, and a crust forms from the exudate: a thick, yellow crust in streptococcal impetigo and a thin, clear crust in staphylococcal impetigo. Both forms usually produce painless itching.
Nummular or annular dermatitis
With nummular or annular dermatitis, numerous coinlike (nummular) or ringed (annular) pustular lesions appear, usually on the extensor surfaces of the extremities, posterior trunk, buttocks, and lower legs; a few lesions may appear on the hands. The lesions commonly ooze a purulent exudate, itch severely, and rapidly become crusted and scaly. A few small, scaling patches may remain for some time.
Pustular miliaria
Pustular miliaria, an anhidrotic disorder, causes pustular lesions that begin as tiny erythematous papulovesicles located at sweat pores. Diffuse erythema may radiate from the lesion. The rash and associated burning and pruritus worsen with sweating.
Rosacea
Rosacea is a chronic hyperemic disorder that commonly produces telangiectasia with acute episodes of pustules, papules, and edema. Characterized by persistent erythema, rosacea may begin as a flush covering the forehead, malar region, nose, and chin. Intermittent episodes gradually become more persistent, and the skin — instead of returning to its normal color — develops varying degrees of erythema.
Scabies
Threadlike channels or burrows under the skin characterize scabies, which can also produce pustules, vesicles, and excoriations. The lesions are a few millimeters long with a swollen nodule or red papule that contains the itch mite.
Smallpox
Initial signs and symptoms of smallpox (variola major) include high fever, malaise, prostration, severe headache, backache, and abdominal pain. A maculopapular rash develops on the mucosa of the mouth, pharynx, face and forearms and then spreads to the trunk and legs. Within 2 days, the rash becomes vesicular and later pustular. The lesions develop at the same time, appear identical, and are more prominent on the face and extremities. The pustules are round, firm, and deeply embedded in the skin. After 8 to 9 days, the pustules form a crust, and later the scab separates from the skin, leaving a pitted scar.
Varicella zoster
When immunity to varicella declines, the virus reactivates along a dermatome, producing extremely painful and pruritic vesicles and pustules (herpes zoster, or shingles). Even with resolution of the rash, patients may experience chronic pain (postherpetic neuralgia) that may persist for months.
Other causes
Drugs
Bromides and iodides commonly cause a pustular rash. Other drug causes include corticotropin, corticosteroids, dactinomycin, trimethadione, lithium, phenytoin, phenobarbital, isoniazid, hormonal contraceptives, androgens, and anabolic steroids.
Special considerations
Observe wound and skin isolation procedures until infection is ruled out by a Gram stain or culture and sensitivity test of the pustule’s contents. If the organism is infectious, don’t allow any drainage to touch unaffected skin.
Pediatric pointers
Among the various disorders that produce pustular rash in children are varicella, erythema toxicum neonatorum, candidiasis, impetigo, infantile acropustulosis, and acrodermatitis enteropathica.
Patient counseling
Instruct the patient to keep his bathroom articles and linens separate from those of other family members. Associated pain and itching, altered body image, and the stress of isolation may result in anxiety, depression, and loss of sleep. Give medications to relieve pain and itching, and encourage the patient to express his feelings.
Pictures



Book Source Details
- Book Title: Signs & Symptoms: A 2-in-1 Reference for Nurses
- Author(s): Springhouse
- Year of Publication: 2007
- Copyright Details: Signs & Symptoms: A 2-in-1 Reference for Nurses, Copyright © 2007 Lippincott Williams & Wilkins.
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Copyright Details: Signs & Symptoms: A 2-in-1 Reference for Nurses, Copyright © 2008 Williams & Wilkins.
More About Causes of Itchy rash
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