Case Number : Case 2253 - 31 January 2019 Posted By: Raul Perret

Sporotrichosis

Dermal suppurative and epithelioid granuloma with a vague zoning pattern: inner suppurative zone with neutrophils, mid zone of epithelioid granuloma with giant cells and outer zone showing lymphoplasmcytic inflammatory cell infiltrates. this pattern does bring cutaneous Sporotrichosis into consideration. I did not see clearly fungal yeasts or the so called Splendore-Hoeppli phenomena. but maybe missed it, Raul, do you have GMS image to show us? so far, also favor sporotrichosis.

What about a Mycobacterium Marinum-related granuloma(fishtank or swimming-pool or aquarium)?

infective granuloma

special stains like GMS/AFB needed

Suppurative granulomatous inflammation suggests a deep fungal infection or atypical mycobacterial infection. Etiologic diagnosis is by special stains and culture of the piece of tissue. 

Suppurative granulomatous inflammation whitout a epidermal changes (quite rare in my experience for sporotrichosis) make me think in Atypical Mycobacterium Infeccion. Marinum is a great suggestion.

Mycobacterium Marinum.

Great comments. This was a suppurative and granulomatous dermatitis due to Mycobacterium Marinum. The patient was a duck breeder who mentienod frequently hurting his hands while handling the animals.

I think the most important lesson of this case is that this histological pattern is virtually always associated with an infectious etiology (either fungus or BAAR). However, do remember that the sensitivity of BAAR staining for detecting microorganisms is quite low in histological sections (I did 6 Ziehl-Neelsen stainings in this case and did not find a single bug!). In spite of this aspect, the probable infectious etiology should be mentioned in the report.