Impetigo is considered as a benign and highly contagious skin infection affecting the epidermis appearing everywhere on the body. Usually it occurs in exposed areas like the nose, mouth, arms, and legs.
Presentation
Characteristic yellow crusted lesions which are most commonly found on the face, typically there are also scattered surrounding lesions called satellite lesions. This starts out as vesicular lesions that are rarely painful. A less common form is bullous impetigo which is presented by larger blisters occurring on the trunk or diaper area of children. Ecthyma is more serious form of impetigo that penetrates deeply into skin causing painful collection of fluid or pus filled sores that turn into deep ulcers.
Entire Body System
- Fever
Symptoms of fever and swollen glands are more common in cases of bullous impetigo. [nhsinform.scot]
Patients may experience fever, hypertension, edema and hematuria. [ncbi.nlm.nih.gov]
Rheumatic fever Group A streptococcal skin infections have rarely been linked to cases of rheumatic fever and rheumatic heart disease. [dermnetnz.org]
Lymph nodes in the affected area may be swollen, but fever is rare. [en.wikipedia.org]
Fever and swollen glands are common with this type of impetigo. [medicalnewstoday.com]
Skin
- Blister
Check if you have impetigo Impetigo starts with red sores or blisters, but the redness may be harder to see in brown and black skin. The sores or blisters quickly burst and leave crusty, golden-brown patches. [nhs.uk]
It usually starts with reddish spots that develop into small red blisters around the mouth and nose. The blisters range in size from 1 to 2 centimeters in diameter (.39 to .78 inch) ( 9 ). The clusters of blisters may spread to other skin areas. [healthline.com]
However, this is more often the result of someone scratching at blisters, crusts or sores. The blisters and crusts themselves should not leave a scar if left to heal. [nhsinform.scot]
PubMed was used to search the following terms, separately and in combination: blister, blistering, bullous, gestationis, herpes, herpetiformis, impetigo, pemphigoid, pregnancy, pregnant, psoriasis, pustular, virus. [ncbi.nlm.nih.gov]
Blisters usually appear first on the torso, arms, and legs. These blisters may initially appear clear and then turn cloudy. Blisters caused by bullous impetigo tend to last longer than blisters caused by other types of impetigo. [web.archive.org]
- Eczema
Possible causes of symptoms Skin symptoms Possible cause Blisters on lips or around the mouth Cold sores Itchy, dry, cracked, sore Eczema Itchy blisters Shingles, chickenpox Non-urgent advice: See a GP if you or your child: might have impetigo had treatment [nhs.uk]
Other people also read: Eczema : the symptoms. Atopic dermatitis : features of atopic eczema. Diabetics : what causes diabetes? Last updated 13.01.2014 [netdoctor.co.uk]
Atopic eczema is a common risk factor; others include bites, trauma to the skin, scabies, chickenpox, burns and contact dermatitis. [patient.info]
Preventing re-infection To reduce the risk of impetigo returning, make sure any cuts, scratches or bites are kept clean, and ensure any condition that causes broken skin, such as eczema, is treated promptly. [nhsinform.scot]
Especially at the early stage of the infection, diagnosis is difficult because it is often misdiagnosed as eczema. We report a case of T. tonsurans infection that had impetigo-like appearance. We also studied the mechanism of the disease. [ncbi.nlm.nih.gov]
- Honey-Colored Crust
After several days, the blisters and pustules rupture and weep, forming the classic honey-colored crusts. [innerbody.com]
Over about a week, the sores burst and develop honey-colored crusts. Treatment with antibiotics can limit the spread of impetigo to others. [mayoclinic.org]
When these blisters pop they will then demonstrate the same honey colored crust. These are often not painful. Is impetigo dangerous? Impetigo on its own is not dangerous, and typically responds well to treatment. [dermatologyofct.com]
The bullae burst and expose larger bases, which become covered with honey-colored varnish or crust. Ecthyma is characterized by small, purulent, shallow, punched-out ulcers with thick, brown-black crusts and surrounding erythema. [merck.com]
The blisters burst and expose raw skin, which becomes covered with honey-colored crust. Ecthyma is characterized by small, shallow ulcers that have a punched-out appearance and sometimes contain pus. [merckmanuals.com]
- Eruptions
A 41-year-old man visited our dermatology clinic because an eruption, which was resistant to steroid ointment treatment, had appeared on his right forearm. [ncbi.nlm.nih.gov]
Impetigo starts as red blisters that later erupt and form yellow, crusty sores. Topical antibiotics may be used to treat the condition. Impetigo is contagious. Uninfected individuals should avoid contact with the lesions. [emedicinehealth.com]
The eruption appears clinically similar to non-bullous impetigo. Usually S. aureus is involved. The underlying skin disease may improve with successful treatment of the impetigo, and the converse may also be true. [pedclerk.bsd.uchicago.edu]
- Skin Rash
Last Updated: Mar 1, 2019 Overview Impetigo is a skin infection caused by bacteria, resulting in a red rash, blisters, and a characteristic honey-colored crust on the skin. Impetigo most commonly occurs in infants and children age 2 to 6. [innerbody.com]
The nonbullous form presents with a maculopapular skin rash that includes small vesicles. These vesicles are known to rupture and form pruritic skin erosions and honey-colored crust. [lecturio.com]
For patient education information, see the Bacterial and Viral Infections Center and Skin, Hair, and Nails Center, as well as Impetigo, Skin Rashes in Children, and Antibiotics. [emedicine.com]
Workup
Diagnosis is mainly by clinical examination by a dermatologist. Assays of streptococcal antibodies are of no value in the diagnosis and treatment of impetigo, but they provide helpful supporting evidence of recent streptococcal infection in patients suspected of having post-streptococcal glomerulonephritis. The anti-streptolysin O response is weak in patients with streptococcal impetigo, presumably because skin lipids suppress streptolysin O response, but anti-DNAase B levels are consistently elevated.
Treatment
Generally, the clinical course and treatment of impetigo depends on many factors including number of lesions, location of lesions, and the urgent need to limit spread of infection to other households or other persons in contact. If the case is presented only by small localized lesions, topical antibacterials like hydrogen peroxide and mupirocin ointments may be used for up to two weeks. In patients who do not respond to topical therapy, or those with impetigous lesions spreading in larger areas, lymphoedematous conditions or systemic illness oral antibiotics may be used like oral Flucloxacillin 500 mg four times daily for 7 days.
Other alternatives include Cephalexin 25 mg/kg/day in 4 divided doses for childeren. If patient is allergic to penicillins Erythromycin (which was in past the mainstay of pyoderma treatment) may be used. Clindamycin is generally effective treatment for skin bacterial infections including impetigo. If there is no response to treatment, courses of topical antibiotics should not be repeated. Instead, swabs to exclude resistant organisms should be done and proper therapy for underlying sensitive strains considered [9]. In severe cases, intravenous antibiotics may be used to treat and control the spread of impetigo [10].
Prognosis
Impetigo may be self-limiting within two to three weeks, but antibiotics can shorten the course of the disease and help prevent the spread to others [7]. Superficial crusts and blisters of impetigo usually do not leave scars. Red skin lesions last for weeks, but redness fades within days to weeks.
Suppurative lesions from streptococcal impetigo are not a common complication. One potentially serious, but rare (only in 1% of cases) complication of impetigo caused by streptococcus bacteria is acute glomerulonephritis and rheumatic fever [8]. The ulcerative scarring which is associated with a deeper and more serious form of impetigo (e.g. ecthyma) can leave permanent scars.
Etiology
It is commonly caused by beta hemolytic streptococci and/or Staphylococcus aureus. These are the usual microorganisms that colonize the unbroken skin. These gram positive strains are often times easily treatable, but impetigo may also be caused by methicillin-resistant and gentamycin-resistant strains of Staphylococcus aureus [3].
Epidemiology
Impetigo is common through the world but it is most frequent among children in the lower economic strata in tropical or subtropical regions. The disorder is also seen to be prevalent in northern regions during the summer and fall months [4]. Its peak incidence is among children with age two to five years, although older children and adults may also be afflicted. There is no sex predilection, and all races are susceptible. Impetigo infections are more common in summer. Participation in sports that involve skin to skin contact, such as football and wrestling increases your risk of developing impetigo. The causative bacteria often enter the skin through a small skin injury, insect bites or rash. The international mean incidence of impetigo is 10-22 cases per 1000 population per year depending on the geographic location [5]. Older adults and people with diabetes or a compromised immune system are more likely to develop ecthyma which is a deeper and more serious form of impetigo that usually leaves scars.
Pathophysiology
Research studies of streptococcal impetigo have elucidated that the causative microorganisms initially colonize the intact skin; thus, proper personal hygiene can directly subdue the disease incidence. Inoculation of surface organisms into the skin by abrasions, minor trauma, or insect bites (pediculosis) then ensues [6]. During the course of two to three weeks, streptococcal strains may be transferred from the skin and impetigo lesions to the upper respiratory tract. In contrast, in patients with staphylococcal impetigo, the pathogens are usually present in the nose before causing cutaneous disease.
Bullous impetigo is caused by strains of Staphylococcus aureus that produce a toxin causing cleavage in the superficial layers of skin. In past, non bullous lesions were usually caused by streptococci. Now, most cases of impetigo are caused by staphylococci alone or in combination with streptococci. Streptococci isolated from lesions are primarily group A organisms, but occasionally, other serogroups (such as C and G) are responsible.
Prevention
Wash your hands or hands of your child after touching patches of impetigo. Usage of towels, flannels, and other fomites should be personal until the infection is eradicated. Children with impetigo should stay off school until there is no crusting.
Summary
Impetigo is considered the most common bacterial skin infection in children. It may appear primarily or may occur as a secondary bacterial infection on abrasions and lacerations of the skin [1]. Impetigo usually resolves in 2-3 weeks but the use of antibiotics can shorten its course and prevent it from spreading. It may occur as bullous and non-bullous forms and 70% of these cases are in non-bullous forms especially in the pediatric age group [2].
Patient Information
Definition
Impetigo is a benign and highly contagious skin infection affecting epidermis appearing everywhere on the body, but usually occurs in exposed areas like the nose, mouth, arms, and legs.
Cause
Impetigo is caused by Staphylococcus aureus and Beta hemolytic Streptococcus.
Symptoms
Non-tender vesicular lesions that progresses to crusting lesions that’s spreads in the epidermis are the typical symptom.
Diagnosis
Diagnosis is by mean of direct physical examination of the skin surface.
Treatment and follow-up
Topical hydrogen peroxide, mupirocin, clindamycin and bacitracin. Intravenous and oral antibiotics may be taken to prevent the aggressive spread of the infection.
References
- Moulin F, Quinet B, Raymond J, Gillet Y, Cohen R. [Managing children skin and soft tissue infections]. Arch Pediatr. Oct 2008; 15 Suppl 2:S62-7.
- Cole C, Gazewood J. Diagnosis and treatment of impetigo. Am Fam Physician. Mar 15 2007; 75(6):859-64.
- Kuniyuki S, Nakano K, Maekawa N, Suzuki S. Topical antibiotic treatment of impetigo with tetracycline. J Dermatol. Oct 2005; 32(10):788-92.
- Loffeld A, Davies P, Lewis A, Moss C. Seasonal occurrence of impetigo: a retrospective 8-year review (1996-2003). Clin Exp Dermatol. Sep 2005; 30(5):512-4.
- Razmjou RG, Willemsen SP, Koning S, et al. Determinants of regional differences in the incidence of impetigo. Environ Res. Jul 2009; 109(5):590-3.
- Treating impetigo in primary care. Drug Ther Bull. Jan 2007; 45(1):2-4.
- Patrizi A, Raone B, Savoia F, Ricci G, Neri I. Recurrent toxin-mediated perineal erythema: eleven pediatric cases. Arch Dermatol. Feb 2008; 144(2):239-43.
- Parks T, Smeesters PR, Steer AC. Streptococcal skin infection and rheumatic heart disease. Curr Opin Infect Dis. Apr 2012; 25(2):145-53.
- Bernard P. Management of common bacterial infections of the skin. Curr Opin Infect Dis. Apr 2008; 21(2):122-8.
- American Academy of Pediatrics. Group A Streptococcal infections. In: Pickering LK, ed. Red Book: 2012 Report of the Committee on Infectious Diseases. 29th ed. Elk Grove Village, Ill: American Academy of Pediatrics; 2012:668-680.