Skin infections may cause itchy rashes in the armpits, especially in hot, humid climates. The intensity of itching is varied in different conditions and is always accompanied by specific skin rashes, which makes the diagnosis and treatment of these types of itchy armpits easier than those without any visible skin rashes.
Skin Infections Causing Underarm Itch & Rash: Diagnosis and Treatment
Following are common skin infections that cause itchy, at times painful, skin rashes in the armpits:
- Erythrasma. Erythrasma, caused by coryneform bacteria, presents as reddish brown or brownish black patches in the armpit and other body folds. Erythrasma is common in the obese and persons suffering from diabetes and other debilitating conditions; poor hygiene is a contributing factor. Usually asymptomatic, in hot humid conditions, it can cause itching. Topical antibiotics, and, if extensive, oral antibiotics are curative if used over a period of two to three weeks.
- Trichomycosis axillaris. The name is misleading as it is not a fungal infection. Like erythrasma, trichomycosis axillaris is caused by different species of coryneform bacteria. The armpit hairs show yellow or reddish yellow concretions, as if greasy dirt is stuck on to the hair shaft. Excessive sweating and hot, humid conditions predispose individuals to trichomycosis axillaris. Usually asymptomatic, it can cause an itchy discomfort in the axilla. Cleansing with antiseptic lotions and use of antibiotic creams after shaving off the underarm hairs are effective steps in getting rid of trichomycosis axillaris. 1% aqueous formalin is useful in refractory cases. Regular use of anti-perspirants is helpful in avoiding recurrences.
- Streptococcal intertrigo. Infection by the bacteria streptococci can cause itchy red rashes in the armpits. Left untreated, this can progress to painful fissures, a not so uncommon occurrence in debilitated patients and infants brought up in unhygienic conditions. Cleansing with antiseptic solutions and application of bactroban usually clear the infections, though oral antibiotics may be necessary in some cases. Other causes of intertrigo also have to be considered.
- Folliculitis. Infections of the hair follicles caused by streptococci or staphylococci can cause itchy, painful, pus-filled bumps in the armpits. These can appear after shaving, waxing or outdoor activities. Topical antibiotics like fucidin are useful in getting rid of the infection in the axillary fold.
- Fungal infections. Ring worm or tinea infections can cause underarm itching, though less common than the groin fungal infections. Avoiding occlusive clothes, keeping the area dry and application of topical antifungal creams like clotrimazole or miconazole for a period of two to three weeks usually get rid of the armpit itching caused by the ringworm.
- Yeast infections. Candidal infections of the armpits are common in infants and the obese and present as red, denuded rashes with small satellite lesions around. This can cause intense itchiness and burning sensation in the affected area.
- Pityriasis versicolor, another yeast infection, causes brown or white patches in the axilla, face, neck and other parts of the trunk. Though mostly asymptomatic, pityriasis versicolor can cause itching of the armpits in hot, humid conditions. Diabetes, sweating, constant washing and occlusion due to the apposing skin surfaces are the main predisposing factors in the yeast infections of the armpits. Treatment is with topical and/or systemic anti-yeast medications.
Skin Infestations Causing Itchy Armpits and Rashes
Scabies caused by the itch mite Sarcoptes scabei and Pediculosis pubis caused by the pubic lice are the most common skin infestations that may cause underarm itching and rashes.
- Scabies. Caused by the itch mite, scabies is an intensely itchy skin disease which may affect the whole family. The itching in scabies is typically at night. The telltale burrows and bumps are present in the anterior fold of the armpit, in addition to other classical sites like the wrist, between fingers, inner side of elbows below the breast and, in males, on the penis and scrotum. At times, in the armpits and the male genitalia, scabies can cause intensely itchy deep seated nodules. The whole family should be treated with anti-scabetic medications like permethrin 5% cream or lotion.
- Pediculosis pubis. Seen as brownish gray specks at the hair roots, the pubic lice may infest the axilla also and cause incessant itching for weeks to months before a definite diagnosis is made by a vigilant patient or a health professional. All close contacts should be treated. Permethrin 1% is the medication of choice.
Skin infections as a cause for itchy rashes in the armpits are easily diagnosed, and, except in a few cases like hidradenitis suppuritiva, curable with specific medications targeted at the infectious germs.
Itchy Armpits Caused by Skin Infections: Related Articles
- Itchy Armpits: Cause and Treatment of Underarm Itching
- Allergic Itchy Armpits: Causes and Treatment of Underarm Itching
- Skin Diseases Causing Underarm Itching : Diagnosis and Treatment
References:
- Fitzpatrick’s Dermatology in General Medicine. Seventh Edition, 2008
- Fitzpatrick's Color Atlas & Synopsis of Clinical Dermatology, Sixth Ed, 2009
Disclaimer
The information given in this article is for educational purposes only so that patients are aware of the options available. No diagnosis should be made or treatment undertaken without first consulting your doctor. If you do so, Dr.Hanish Babu, MD or Suite101 will not be responsible for any consequences. The images provided are for illustration purposes only.
Hanish Babu - Dr.Hanish Babu, MD is a dermatologist and a feature writer on Suite101.com with more than 200 articles related to skin diseases on the ...
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