Read on Twitter
Q: (1/2)35/Farmer from Missouri AML s/p HSCT 6m ago. GVHD on steroids. Admitted with sepsis. (-) travel. CXR clear. WBC 7K . ANC 1.5K. Eczema like lesions on leg. (See next thread)
Q(2/2)
Skin lesion Bx & cx: pseudo epitheliomatous hyperplasia with granulomatous inflam + organisms with round sporangia + endospores.
Blood Cx : + (representative pic-wet mount of culture colony -lactophenol CB ), (pic courtesy @paulywogPhD)
What is the likely diagnosis ?
Skin lesion Bx & cx: pseudo epitheliomatous hyperplasia with granulomatous inflam + organisms with round sporangia + endospores.
Blood Cx : + (representative pic-wet mount of culture colony -lactophenol CB ), (pic courtesy @paulywogPhD)
What is the likely diagnosis ?
1/8) Answer :
Congratulations ! The majority identified this correctly as Protothecosis.
Human infection is rare -
* caused by genus (you guessed it) Prototheca.
* generally considered to be achlorophyllic algae
* ubiquitous in nature
* microscopic single-cell structures
Congratulations ! The majority identified this correctly as Protothecosis.
Human infection is rare -
* caused by genus (you guessed it) Prototheca.
* generally considered to be achlorophyllic algae
* ubiquitous in nature
* microscopic single-cell structures
2/8) Pathogenesis :
* 2 species P. wickerhamii and P. zopfii infect humans
* source is usually contact with contaminated soil or water /after traumatic inoculation with algae
* occurs most commonly among immunosuppressed (IS)
* 2 species P. wickerhamii and P. zopfii infect humans
* source is usually contact with contaminated soil or water /after traumatic inoculation with algae
* occurs most commonly among immunosuppressed (IS)
3/8) 3 clinical forms:
(i) cutaneous lesions,
(ii) olecranon bursitis, and
(iii) disseminated or systemic infections
(i) cutaneous lesions,
(ii) olecranon bursitis, and
(iii) disseminated or systemic infections
4/8) Cutaneous protothecosis
* skin most commonly involved organ
* >half associated with immunosuppression.
* usually single lesion. Typically- vesiculobullous and ulcerative lesion associated with purulent discharge and crusting
* skin most commonly involved organ
* >half associated with immunosuppression.
* usually single lesion. Typically- vesiculobullous and ulcerative lesion associated with purulent discharge and crusting
5/8) Olecranon bursitis
* usually immunocompetent
* subacute to chronic symptoms, weeks after trauma
Disseminated disease :
* Associated with immunosuppression or catheter related sepsis
* Organs affected - skin, subcutaneous tissue, spleen, GI with or without algemia
* usually immunocompetent
* subacute to chronic symptoms, weeks after trauma
Disseminated disease :
* Associated with immunosuppression or catheter related sepsis
* Organs affected - skin, subcutaneous tissue, spleen, GI with or without algemia
Diagnosis
Consider in high risk groups or with specific synd. (olec. bursitis)
Micro : growth in 3-5d. Wet mt with lactophenol cotton blue demonstrates sporangia with endospores
grpd. together ->morulae with a daisy shape (see pic above - special thx @paulywogPhD for sharing)
Consider in high risk groups or with specific synd. (olec. bursitis)
Micro : growth in 3-5d. Wet mt with lactophenol cotton blue demonstrates sporangia with endospores
grpd. together ->morulae with a daisy shape (see pic above - special thx @paulywogPhD for sharing)
7/8) Diagnosis
Skin biopsy : typically pseudoepitheliomatous hyperplasia with granuloma formation. PAS or GMS reveal characteristic sporangia with endospores https://www.sciencedirect.com/science/article/pii/S0738081X11002951?via%3Dihub
Skin biopsy : typically pseudoepitheliomatous hyperplasia with granuloma formation. PAS or GMS reveal characteristic sporangia with endospores https://www.sciencedirect.com/science/article/pii/S0738081X11002951?via%3Dihub
8/8) Treatment :
limited data- optimal Rx uncertain
* surgical resection/debridement if possible
* Rx azoles or amphotericin derivatives. (prototheca have ergosterol in the cell membranes)
* resistant to 5-flucytosine
See review - https://cmr.asm.org/content/20/2/230
limited data- optimal Rx uncertain
* surgical resection/debridement if possible
* Rx azoles or amphotericin derivatives. (prototheca have ergosterol in the cell membranes)
* resistant to 5-flucytosine
See review - https://cmr.asm.org/content/20/2/230
