Introduction:
This article is about pruritic annular bumps present on the extremities. This benign skin condition is characterized by one to two-millimeter-sized erythematous or skin-colored papules that tend to form annular papules. The feet, arms, and legs are the sites where blemishes are found. The umbilicated dorsum of the papules is limited to the dorsum of the hands and feet. In many cases, it involves the small joints of the hand. This is also called a granuloma annulare that is present at the periphery of the nodules.
What Are Pruritic Annular Papules?
Pruritic annular papules are a common inflammatory skin condition that shows clinically annular, smooth, discolored papules or plaques. It is characterized by raised annular distribution. This condition may be localized, generalized, perforated, or subcutaneous. One to two millimeters of papules are seen in annular arrangement over the distal extremities ranging from the color of the skin to erythematous in appearance.
Who Gets Pruritic Annular Papules?
Granuloma annulare is mostly seen in the skin of children, teenagers, or young adults. The generalized form is most likely seen in older adults aged around 50 years. The females outnumber the males by nearly a factor of two.
What Is the Cause of Pruritic Annular Papules?
Pruritic annular papules may occur due to the delayed hypersensitivity reaction seen in the dermis or a reaction pattern involving numerous triggers. Triggering may include many skin infections, infestations, and skin trauma. Inflammation is caused by tumor necrosis factor alpha. The reason for causing this condition was unknown. Numerous conditions are associated with it which includes:
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Autoimmune thyroiditis.
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Hyperlipidemia.
In addition, it can be associated with rare conditions like the following:
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HIV (human immunodeficiency virus) infection.
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Solid tumors.
What Are the Clinical Features of Pruritic Annular Papules?
Granuloma annulare can occur in any site of the body and is very occasionally widespread. It only affects the skin of the body. These pruritic annular papules may cause no symptoms. But the affected areas may often be tender and knocked. Papules may slowly change in shape, size, and position. The clinical features of different types of pruritic annular papules are listed below:
Localized Granuloma Annulare:
The localized form of annulare is the most common type of granuloma that is generally and specifically seen in children. One or more red bumps from the rings are seen in the skin over the joints, particularly on the joints' knuckle area. They are smooth, and the center of each ring is depressed. The localized form of granuloma annulare was usually affecting the fingers or the backs of both hands. It is commonly seen on the upper surface of the ankle and foot and over one or both elbows. These annular rings may be multiple or solitary and grow outwards by maintaining the ring shape before eventually clearing.
Generalized Disseminated Granuloma:
Generalized forms of granuloma are usually seen in adults as widespread skin-colored lesions that may be pinkish or mauve-colored patches. These types of disseminated generalized papules are composed of smaller papules that are usually arranged symmetrically in forms of poorly defined rings around 10 centimeters or more in diameter. They are mostly seen on the skin fold of the trunk, including the armpit and groin. Itching is commonly seen. This is most commonly associated with HIV patients.
Subcutaneous Granuloma Annulare:
This subcutaneous type of granuloma annulare was an uncommon condition that was mainly seen in children. It presents with rubbery lumps on the scalp margins, fingertips, and shins. This subcutaneous type is also called pseudo rheumatoid nodules that are not associated with rheumatoid arthritis.
Perforating Granuloma Annulare:
Perforating type of granuloma annulare presents as yellowish plaques or papules on which the crust forms are seen due to the elimination of the damaged collagen through the epidermis. Usually seen localized to the hands, the plaques may be seen occasionally that arise on any site of the body. Dermoscopy is used to confirm the presence of perforations in the small papules. Perforating types of granuloma are frequently itching and tender.
Atypical Granuloma Annulare:
Atypical granuloma annulare shows:
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Granuloma annulare is seen in unusual sites such as the palms, face, and ears.
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Photosensitive distribution.
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An unusually severe or symptomatic form of granuloma annulare.
Interstitial Granulomatous Dermatitis:
Interstitial granulomatous dermatitis is noted in some cases of histology findings where the patient is seen with extensive granuloma annulare. It also has other skin disorders with similar clinical features.
How Is Granuloma Annulare Diagnosed?
Granuloma annulare is usually diagnosed because of the characteristic appearance of the disease. In some cases, the diagnosis may not be accurate, and other conditions may also be considered. This skin biopsy usually shows the necrobiosis form of dermal collagen degeneration surrounded by inflammatory reactions. This granuloma annulare is sometimes diagnosed as a tinea condition due to the annular appearance and lack of surface scaling that leads away from the other scaly rashes, such as discoid eczema or psoriasis. Some considered actinic granuloma as a photo-aggravated variant form of granuloma by others.
What Is the Treatment Option Available for Granuloma Annulare?
In most cases of granuloma annulare, that does not require treatment since the patches formed may disappear by themselves in a few months, clearing with no trace. Sometimes they persist for about years. The treatment may not be curative but may help in individual lesions.
Local Therapy:
Local therapy options include the following:
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Topical corticosteroid ointment.
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Intralesional steroid injections.
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The destruction is caused by cryotherapy or laser ablation.
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Imiquimod cream.
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A topical form of calcineurin inhibitors.
Systemic Therapy:
Systemic treatment is considered in widespread granuloma annulare conditions. The following treatment option may be helpful in some cases of disseminated granuloma annulare. None of the following can completely clear it, and potential adverse effects are also seen.
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Methotrexate.
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Dapsone.
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Hydroxychloroquine.
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Potassium iodine.
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Isotretinoin.
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Photodynamic therapy.
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Ciclosporin.
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Combination of antibiotics once monthly: Rifampin, Ofloxacin, and Minocycline.
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Systemic steroids.
Conclusion:
This individual lesion of the localized granuloma tends to be cleared within a few months or years, although they may recur even at the same site. In the case of generalized and atypical variants, they are more persistent and sometimes can last for decades.
