ContentsSynopsisCodesLook ForDiagnostic PearlsDifferential Diagnosis & PitfallsBest TestsManagement PearlsTherapyReferencesView all Images (5)
Alternariosis - Skin
Print
Other Resources UpToDate PubMed

Alternariosis - Skin

Print Images (5)
Contributors: Amanda Robinson MD, Alexa Kimball MD, Jeffrey D. Bernhard MD, Noah Craft MD, PhD, Lindy P. Fox MD, Lowell A. Goldsmith MD, MPH, Michael D. Tharp MD
Other Resources UpToDate PubMed

Synopsis

Alternaria is the genus for a dematiaceous hyphomycete (conidial fungi that produce dark brown, green-black, or black colonies) found in the soil, in decaying plant material, and on normal human and animal skin. Alternaria has been associated with hypersensitivity pneumonitis, bronchial asthma, and allergic sinusitis and rhinitis. It can be pathogenic in humans, most often in immunocompromised hosts. Multiple clinical manifestations have been documented including ocular infections, onychomycosis, cutaneous and subcutaneous infections, granulomatous pulmonary disease, soft palate perforation, and disseminated disease. Cutaneous infection occurs either by traumatic inoculation of fungal elements into the skin or by systemic spread.

The two species most frequently isolated from clinical samples are A. alternata and A. infectoria. Microscopically, Alternaria spp. appear as branched septate hyphae with hand grenade-shaped conidia. On histology, a mixed inflammatory infiltrate and granulomas are typical. Granuloma formation is usually observed in older lesions that have been present for at least 3-months evolution. Hyphal elements are usually present and can be visualized with Fontana-Masson staining.

Codes

ICD10CM:
B48.8 – Other specified mycoses

SNOMEDCT:
238436005 – Cutaneous alternariosis

Look For

Subscription Required

Diagnostic Pearls

Subscription Required

Differential Diagnosis & Pitfalls

Diagnosis of alternariosis requires both histologic and mycologic analyses of a biopsy sample. Histologic examination reveals hyperkeratosis, parakeratosis, granulomatous inflammation, and fungal elements. Fungal elements may also be seen on KOH. Alternaria fungi may be cultured from the lesion. Fungal cultures can be difficult, at times taking months to identify the organism. Differentiate Alternaria from other invasive fungal organisms by their dark color and by comparison of hyphal elements. The filaments of Aspergillus and Fusarium are smaller in diameter, and its branch points are more acute; mucormycosis hyphae are wider and non-septate compared with alternariosis.

Best Tests

Subscription Required

Management Pearls

Subscription Required

Therapy

Subscription Required

References

Subscription Required

Last Updated: 09/12/2011
Copyright © 2019 VisualDx®. All rights reserved.
Alternariosis - Skin
Print 5 Images
View all Images (5)
(with subscription)
Alternariosis : Gardener, Plaque with ulcer, Skin trauma site
Clinical image of Alternariosis
Copyright © 2019 VisualDx®. All rights reserved.