What are the other Names for this Condition? (Also known as/Synonyms)

• Granulomatous Dermatitis caused by Infections
• IGD (Infectious Granulomatous Dermatitis)

What is Infectious Granulomatous Dermatitis? (Definition/Background Information)

• Infectious Granulomatous Dermatitis (IGD) is a form of granulomatous dermatitis, an uncommon skin condition, which presents skin rashes with certain infections such as leprosy, cutaneous tuberculosis, and fungal infections
• The treatment of Infectious Granulomatous Dermatitis is based on the signs and symptoms, which may wax and wane, and the associated infection. With adequate treatment of the associated infection, IGD is known to improve or resolve completely

Who gets Infectious Granulomatous Dermatitis? (Age and Sex Distribution)

• Infectious Granulomatous Dermatitis may be observed in children and adults. According to medical literature, an age range of 7 to 80 years is observed
• Both males and females are known to be affected; it is reported that a greater number of cases are generally seen in females
• The condition may affect individuals of all racial and ethnic groups

What are the Risk Factors for Infectious Granulomatous Dermatitis? (Predisposing Factors)

The following infections are associated with Infectious Granulomatous Dermatitis (IGD):

• Leprosy: Worldwide, it is the most common disease observed with IGD; around 70-75% of IGD develop in the setting of leprosy
• Skin tuberculosis (lupus vulgaris and scrofuloderma): Worldwide, it is the second-most common disease observed with IGD; representing around 20-23% of the cases

Leprosy and tuberculosis are caused by bacteria in the Mycobacteria family. These are less common mycobacterial organisms that live in water and soil causing diseases in humans, including Infectious Granulomatous Dermatitis. These so-called “atypical mycobacteria” are the most common cause of Infectious Granulomatous Dermatitis in the USA.

• Fungal infections including aspergillosis, candidiasis, cryptococcosis, histoplasmosis, and sporotrichosis
• Milker’s nodule
• Parasitic granuloma due to dirofilariasis, leishmaniasis, and schistosomiasis
• Syphilis

Less commonly, the following bacterial, fungal, and viral infections have been implicated:

• Actinomycosis
• Brucellosis
• Cat-scratch disease
• Cytomegalovirus (CMV) infection
• Epstein-Barr virus (EBV) infection
• Measles
• Melioidosis
• Nocardiosis
• Q-fever
• Whipple’s disease

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Infectious Granulomatous Dermatitis? (Etiology)

• The exact cause of formation of Infectious Granulomatous Dermatitis (IGD) is unknown. The granulomatous lesions is believed to develop as a reactive process of the body to certain antigens in the body
• This chronic inflammatory skin condition is noted in individuals with a wide variety of infections; the common pathogens being mycobacteria (causing leprosy and tuberculosis) and fungi

What are the Signs and Symptoms of Infectious Granulomatous Dermatitis?

The signs and symptoms of Infectious Granulomatous Dermatitis may be mild or severe and may depend on the associated infection. The signs and symptoms may vary widely from one individual to another, and may include:

• Presence of numerous papules, plaques, and nodules
• These granulomatous skin lesions may range in color from buff-colored, pink, to red
• Any part of the body may be affected such as the trunk, upper and lower limbs, and face and neck region 
• The lesions may present itching to burning sensation
• Lesions may ulcerate and bleed
• The skin lesions may be present for several days to months; a waxing and waning of the lesions may be noted

Additional signs and symptoms of the associated infection may be noted.

How is Infectious Granulomatous Dermatitis Diagnosed?

Generally, a diagnosis of Infectious Granulomatous Dermatitis is difficult and challenging. The following tests and exams may be used in diagnosing the condition:

• Evaluating the clinical history (physical exam) and a thorough family history (including history of autoimmune disease and current medication use)
• Dermoscopy: It is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Wood’s lamp examination: In this procedure, the healthcare provider examines the skin using ultraviolet light. It is performed to examine the change in skin pigmentation
• KOH tests to rule out a fungal infection
• Complete blood count (CBC), antibody tests, and tissue culture
• Polymerase chain reaction (PCR) assay
• Skin tissue biopsy: A tissue biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis
• Tissue to culture for fungal and atypical mycobacterial infections

Tests and procedures to diagnose the associated infection is important.

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Infectious Granulomatous Dermatitis?

The complications of Infectious Granulomatous Dermatitis may include:

• Emotional stress
• Cosmetic concerns
• Relapse of the condition
• Treatment complications

Complications of the underlying/associated infection may be noted.

How is Infectious Granulomatous Dermatitis Treated?

The treatment of Infectious Granulomatous Dermatitis (IGD) primarily involves managing the underlying/associated infection. If necessary, a symptomatic treatment of the skin signs and symptoms may be undertaken via the following measures:

• Use of topical steroid creams and ointments
• Oral and systemic steroids, if necessary
• Administration of medications such as dapsone, hydroxychloroquine, and methotrexate

How can Infectious Granulomatous Dermatitis be Prevented?

• Currently, there are no specific preventative measures available for Infectious Granulomatous Dermatitis
• Adequately treating the associated causative infection may lower one’s risk for IGD

What is the Prognosis of Infectious Granulomatous Dermatitis? (Outcomes/Resolutions)

Infectious Granulomatous Dermatitis may improve or resolve with adequate treatment of the associated infection. However, the overall prognosis is dependent upon the severity of the associated infection.

Additional and Relevant Useful Information for Infectious Granulomatous Dermatitis:

Cleaning the skin too hard with strong chemicals or soaps may aggravate the skin condition. Care must be taken avoid strong soaps and chemicals that could potentially worsen the condition.