Case study

By Steven Goldstein, DPM; Basem Halaka, DPM; David Vance, DPM; Jason Weslosky, DPM

History of Present Illness

The patient is a 62 year old male with a 2 year history of thickened, elongated, and yellow discolored nails of the hallux bilateral. The nails appear dystrophic with evidence of subungual debris. The patient does not recall any significant trauma to the nails but does admit to uncomfortable rubbing of the bilateral hallux nails in his shoes. The patient does not have any other contributing medical history.

Work-up

The bilateral nails were debrided and multiple keratogenous samples were sent for analysis (histopathology and PCR). Care was taken to remove debri subungually as well as portions of the proximal nail plate.

Histopathology and Molecular Analysis

Identified in this study were histopathologic features of acute and chronic micro-trauma as well as onychomycosis. Fungal elements were demonstrated with both PAS and GMS stains. Fontana Masson staining was performed as well and was negative for melanin.   PCR testing was performed and was able to identify the organism, a saprophyte of the Fusarium genus.

Q&A with two Bako Diagnostics dermatopathologists:

Kim Whisenant, M.D., and Carolina Montes, M.D. on partnering with podiatrists

Q. What is the importance of podiatrists being familiar with pathology, specifically dermatopathology?

A. Dr. Montes:
The skin is the largest organ of the body, and many medical specialties, including podiatry, come in contact with disorders of the skin. Lesions that appear on the skin, including the foot, can also be a manifestation of internal systemic disease. Consequently, it’s important for clinicians to be familiar with both inflammatory and neoplastic processes of the skin. Dermatopathology is the subspecialty of pathology that provides this knowledge.

A. Dr. Whisenant:
Because many dermatologic lesions – both benign and malignant – are commonly found on the lower extremities, podiatrists have a unique opportunity to evaluate patients and detect these lesions early on. The best way to detect these lesions is to be familiar with the dermatologic and pathologic presentation, and generate a clinical differential diagnosis, properly biopsy the lesion, and receive a more specific diagnosis.

Q. Your team has partnered with thousands of podiatrists to diagnose and treat the lower extremity. When should a podiatrist reach out to a dermatopathologist?

A. Dr. Whisenant:
If a lesion is biopsied incorrectly or sent in the wrong solution — or worse — in no solution, and allowed to air-dry, it can be difficult and sometimes impossible to diagnose. Podiatrists should work with a dermatopathologist when they have questions on specimen collection. The proper specimen collection and submission process is critical to getting to the right treatment.

A. Dr. Montes:
When reviewing Bako’s detailed report, podiatrists are encouraged to ask any questions pertaining to the diagnosis or recommended treatment. Our reporting dermatopathologists are easily accessible and eager to provide the best service.

Q. What should podiatrists consider when submitting a specimen to the lab for analysis and dermatopathologist reading and interpretation?

A. Dr. Whisenant:
When submitting a specimen, be sure the basic requisition forms are complete and add as much specific information as possible – biopsy site, lesion location/description/history, clinical differential diagnosis. In addition, uploading images of your patient’s lesion can be valuable to diagnosis and treatment suggestions. Upload capabilities are available for podiatrists through the Bako Diagnostics web portal.

A. Dr. Montes:
Understanding the appropriate scenarios to use the varying specimen collection techniques (punch, shave, scraping, excision, avulsion, etc.), the correct preservatives to use, and how to avoid sampling artifact – are all key to proper submission and diagnosis. Bako Diagnostics has published the “Lower Extremity Biopsy Techniques,” a Practice Essentials guide for the podiatric medical professional. This is helpful in identifying the best practices for specimen collection. A complimentary copy is available to all podiatrists at https://bit.ly/3sY6yks.

By Morgan Baxter, DPM, Aron Block, DPM, Lillian Youhkana, DPM

Blastomycosis is a type of fungal infection that can be acquired from inhaling fungal spores

History

A 53 year old healthy male presents to clinic with concerns of a rash involving raised bumps for about a month. He thought it was a cluster of warts, but has not had any relief with over the counter topical medications. He does mention that about a month ago, he was raking leaves barefoot. The bumps are not painful but have started to leak and have not gone away. He resides in Ohio near Lake Erie.

A punch biopsy of a representative lesion was submitted.

Histologic findings:

Verrucous lesion with pseudoepitheliomatous hyperplasia and a polymorphous dermal inflammatory cell infiltrate with scattered giant cells and neutrophils with occasional microabcesses.  PAS and GMS stains are positive for thick walled yeasts with broad based budding.  Yeasts, which measure 7-15 micrometers are found in the center of the abscess and sometimes in the giant cells.

Diagnosis

Blastomycosis

Differential Diagnosis

Other cutaneous infections can mimic cutaneous blastomycosis including other endemic mycosis such as histoplasmosis and coccidioidomycosis. It has been found that cutaneous blastomycosis may very closely resemble pyoderma gangrenosum or keratoacantoma or malignancies such as basal cell carcinoma or squamous cell carcinoma. For proper diagnosis a skin biopsy is vital in differentiating blastomycosis infection from these other diseases.

Discussion

Blastomycosis is a type of fungal infection that can be acquired from inhaling fungal spores from the air.   It is found in the United States and Canada and is concentrated in the Ohio and Mississippi river valleys and the Great Lakes region.  Blastomycosis is typically found in soil and decaying organic matter. It manifests as a primary lung infection in the majority of cases.  In individuals with weakened immune systems, the infection can spread to other areas of the body such as the skin. Following pneumonia, cutaneous lesions are the next most common manifestation of blastomycosis. The skin lesions are either verrucous or ulcerative. Bone, prostatic and CNS blastomycosis are also fairly common presentations of this infection. The disease is often misdiagnosed, particularly as malignancy. Search for the organism by microscopy and culture should be considered, even in those with a classic presentation of other illnesses. Most people with blastomycosis will need treatment with prescription antifungal medications. Depending on the severity of the infection, the course of treatment can range from six months to a year. Mild and moderate fungal infections involving the skin and lungs are best treated with Itraconazole. Amphotericin B should be used in severe infections involving the lungs. In conclusion, a thorough history including a geographical location is imperative to help make the accurate diagnosis of a blastomycosis infection.

References:

Chapman SW, Dismukes WE, Proia LA, Bradsher RW, Pappas PG, et al. (2008) Clinical practice guidelines for the management of blastomycosis: 2008 update by the Infectious Diseases Society of America. Clinical Infectious Diseases 46: 1801–1812

Larson DM, Eckman MR, Alber RL, Goldschmidt VG. Primary cutaneous (inoculation) blastomycosis: an occupational hazard to pathologist. Am J Clinc Pathol. 1983;79(2):253–255.

McBride, J. A., Gauthier, G. M., & Klein, B. S. (2017). Clinical Manifestations and Treatment of Blastomycosis. Clinics in chest medicine, 38(3), 435–449. doi:10.1016/j.ccm.2017.04.006

Saccente M, Woods GL. Clinical and laboratory update on blastomycosis. Clin Microbiol Rev. 2010

Smith JA, Riddell J, IV, Kauffman CA. Cutaneous manifestations of endemic mycoses. Curr Infect Dis Rep. 2013;15(5):440–449