History

Fact Explanation
Skin lesion Blastomycosis is a fungal infection caused by Blastomyces dermatitidis. Infection occurs by breathing in the spores that become airborne when contaminated soil or wood is disturbed (Secondary Cutaneous blastomycosis). Very rarely direct contact of non-intact skin with contaminated soil or decomposing timber may occur (Primary Cutaneous blastomycosis). Cutaneous lesions are common on the face, neck and extremities as the infection spreads from the lungs to other parts of the body. Cutaneous manifestation may be solitary or multiple. The lesions often begin as small solid raised lesions that has distinct borders and is less than 1 cm in diameter (papules) or pustules or nodules under the skin. They may be painful. [1,2,3,4,5]
Ulcers Within weeks to months the lesions develop into ulcers and form crusty sores with sharp borders. Over a period of months to years lesions grow larger, disfiguring, and may occupy large portion of the body area. These ulcers may bleed easily. [2,3,4,5]
Scars These ulcers heal to form raised wart-like scars. Lesions may cover much of the face causing severe disfigurement. Irreversible scarring often occurs. [1,3,4,5]
At risk population Though Blastomycosis is distributed throughout the world, it is most common in south-central and mid-western USA and Canada. Immunocompromised individuals such as those with human immunodeficiency virus infection (HIV) or organ transplant recipients are at greater risk of severe disease. [1,4,5]
Accompanying febrile disease Along with the skin disease, patient may have flu like illness caused by blastomycosis infection which is characterized by fever, chills, headache and non-productive cough. Symptoms may resolve within days without treatment or may go undiagnosed. [1,2,3]
Medical history of chronic pulmonary blastamycosis Chronic blastomycosis may simulate lung cancer, or tuberculosis with low-grade fever, weight loss, night sweats, and a productive cough. Sputum is purulent of mucopurulent, hemoptysis may be present. [1,2,3]
Acute respiratory involvement The cutaneous disease sometimes accompanies with acute illness resembling bacterial pneumonia which may present with high fever, chills, productive cough and chest pain. Sputum may be yellowish brown. [2,3,4]
References
  1. SACCENTE M, WOODS GL. Clinical and laboratory update on blastomycosis. Clin Microbiol Rev [online] 2010 Apr, 23(2):367-81 [viewed 12 August 2014] Available from: doi:10.1128/CMR.00056-09
  2. ROSS JJ, KEELING DN. Cutaneous blastomycosis in New Brunswick: case report. CMAJ [online] 2000 Nov 14, 163(10):1303-5 [viewed 12 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/11107468
  3. GHARPURAY MB, MAHAJAN PM, TOLAT SN. Localised cutaneous blastomycosis. Indian J Dermatol Venereol Leprol [online] 1997 Jul-Aug, 63(4):243-5 [viewed 12 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/20944342
  4. BALASARASWATHY P, THEERTHANATH. Cutaneous blastomycosis presenting as non-healing ulcer and responding to oral ketoconazole. Dermatol Online J [online] 2003 Dec, 9(5):19 [viewed 12 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/14996392
  5. GRAY NA, BADDOUR LM. Cutaneous inoculation blastomycosis. Clin Infect Dis [online] 2002 May 15, 34(10):E44-9 [viewed 12 August 2014] Available from: doi:10.1086/339957

Examination

Fact Explanation
Skin lesion More common on the face, neck, and the extremities. In the early disease course, lesions are sharply demarcated papules or pustules, or sometimes as subcutaneous nodules. Simultaneously or sequentially, multiple lesions may appear . [1,2,3,4]
Ulcer The primary lesions will evolve into ulcers, within a few weeks to months with indurated dusky or violaceous granulomatous or verrucous borders, It may also evolve into vegetating plaques. [2,3,4]
Lymphadenopathy Sometimes, patient may have regional tender lymph node enlargement along with lymphangitis. [3,4]
References
  1. SACCENTE M, WOODS GL. Clinical and laboratory update on blastomycosis. Clin Microbiol Rev [online] 2010 Apr, 23(2):367-81 [viewed 12 August 2014] Available from: doi:10.1128/CMR.00056-09
  2. GHARPURAY MB, MAHAJAN PM, TOLAT SN. Localised cutaneous blastomycosis. Indian J Dermatol Venereol Leprol [online] 1997 Jul-Aug, 63(4):243-5 [viewed 12 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/20944342
  3. BALASARASWATHY P, THEERTHANATH. Cutaneous blastomycosis presenting as non-healing ulcer and responding to oral ketoconazole. Dermatol Online J [online] 2003 Dec, 9(5):19 [viewed 12 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/14996392
  4. GRAY NA, BADDOUR LM. Cutaneous inoculation blastomycosis. Clin Infect Dis [online] 2002 May 15, 34(10):E44-9 [viewed 12 August 2014] Available from: doi:10.1086/339957

Differential Diagnoses

Fact Explanation
Furuncle Furuncles (boils) are skin abscesses caused by staphylococcal infection, which involve a hair follicle and surrounding tissue. Boils are bumpy, red, pus-filled lumps around a hair follicle that are tender, warm, and very painful. They range from pea-sized to golf ball-sized. A yellow or white point at the centre of the lump can be seen when the boil is ready to drain or discharge pus. In a severe infection, an individual may experience fever, swollen lymph nodes, and fatigue. [1]
Orf Orf is an infection caused by a parapox virus called by the same name. It is a common among sheep and goats. Direct contact with an infected animal or contaminated fomites results in transmission of the virus to human body. Therefore, Orf is frequently seen in farmers and meat handlers. Orf lesions are generally solitary or few in number. Though the classical site is the dorsum of the index finger, it can be seen on other fingers, hands, forearms or on face. [2]
Pyogenic Granuloma Pyogenic granuloma is a relatively common skin growth that presents as a shiny red mass. It is sometimes called ‘granuloma telangiectaticum’, or lobular capillary angioma. The surface has a raspberry-like or raw minced meat appearance. Although they are benign (non-cancerous), pyogenic granulomas can cause problems of discomfort and profuse bleeding. [3]
Squamous Cell Carcinoma Squamous cell carcinoma (SCC) is a common type of skin cancer. It is derived from squamous cells, the flat cells that make up the outside layers of the skin, the epidermis. These cells are keratinising i.e., they produce keratin, the horny protein that makes up skin, hair and nails. Invasive SCC refers to cancer cells that have grown into the deeper layers of the skin, the dermis. Invasive SCC can rarely metastasize. Invasive SCCs are usually slowly-growing, tender, scaly or crusted lumps. The lesions may develop sores or ulcers that fail to heal. Most SCCs are found on sun-exposed sites, particularly the face, lips, ears, hands, forearms and lower legs. [4]
References
  1. IBLER KS, KROMANN CB. Recurrent furunculosis - challenges and management: a review. Clin Cosmet Investig Dermatol [online] 2014:59-64 [viewed 12 August 2014] Available from: doi:10.2147/CCID.S35302
  2. KITCHEN M, MüLLER H, ZOBL A, WINDISCH A, ROMANI N, HUEMER H. ORF virus infection in a hunter in Western Austria, presumably transmitted by game. Acta Derm Venereol [online] 2014 Mar, 94(2):212-4 [viewed 02 August 2014] Available from: doi:10.2340/00015555-1643
  3. ADUSUMILLI S, YALAMANCHILI PS, MANTHENA S. Pyogenic granuloma near the midline of the oral cavity: A series of case reports. J Indian Soc Periodontol [online] 2014 Mar, 18(2):236-9 [viewed 12 August 2014] Available from: doi:10.4103/0972-124X.131339
  4. AWAN BA, ALZANBAGI H, SAMARGANDI OA, AMMAR H. Scalp squamous cell carcinoma in xeroderma pigmentosum. N Am J Med Sci [online] 2014 Feb, 6(2):105-6 [viewed 04 August 2014] Available from: doi:10.4103/1947-2714.127754

Investigations - for Diagnosis

Fact Explanation
Skin biopsy Histopathological examination may show epidermal hyperplasia, epidermal microabscesses and abscesses, epidermal necrosis, and dermal infiltration with inflammatory cells. The histopathological examination does not differentiate primary from secondary cutaneous blastomycosis. [1,2,3]
References
  1. GRAY NA, BADDOUR LM. Cutaneous inoculation blastomycosis. Clin Infect Dis [online] 2002 May 15, 34(10):E44-9 [viewed 12 August 2014] Available from: doi:10.1086/339957
  2. GHARPURAY MB, MAHAJAN PM, TOLAT SN. Localised cutaneous blastomycosis. Indian J Dermatol Venereol Leprol [online] 1997 Jul-Aug, 63(4):243-5 [viewed 12 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/20944342
  3. BALASARASWATHY P, THEERTHANATH. Cutaneous blastomycosis presenting as non-healing ulcer and responding to oral ketoconazole. Dermatol Online J [online] 2003 Dec, 9(5):19 [viewed 12 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/14996392

Management - Specific Treatments

Fact Explanation
Oral antifungal therapy Various antifungal drugs have been tried in the treatment of cutaneous blastomycosis, and oral triazoles, ketoconazole, fluconazole, and itraconazole, have been found useful. [1,2,3]
Amphotericin B Amphotericin B via intravenous administration is the drug of choice for severe or life-threatening blastomycosis in immunocompromised patients. [2,3]
References
  1. SACCENTE M, WOODS GL. Clinical and laboratory update on blastomycosis. Clin Microbiol Rev [online] 2010 Apr, 23(2):367-81 [viewed 12 August 2014] Available from: doi:10.1128/CMR.00056-09
  2. GRAY NA, BADDOUR LM. Cutaneous inoculation blastomycosis. Clin Infect Dis [online] 2002 May 15, 34(10):E44-9 [viewed 12 August 2014] Available from: doi:10.1086/339957
  3. ROSS JJ, KEELING DN. Cutaneous blastomycosis in New Brunswick: case report. CMAJ [online] 2000 Nov 14, 163(10):1303-5 [viewed 12 August 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/11107468