Lobomycosis

Background:

-  Lobomycosis – an infection caused by Lacazia loboi, previously known as Loboa loboi

o  Kingdom – Fungi

§  Phylum – Zygomycota

·  Genus – Lacazia

o  Species – loboi (only known species of Lacazia)

-  Yeast like fungus

o  Causes infection in humans and bottle nosed dolphins

o  Aquatic environment must be present for life cycle

o  Slow growing with prolonged incubation

-  Strictly located in tropical regions

o  Cultures have been unsuccessful, environment not exactly known

-  A chronic, localized, subepidermal infection characterized by:

o  Kelodial lesion

o  Verrucoid lesion

o  Nodular lesion

o  Crusty plaques and tumors

o  Hypopigmentation

-  Clinical forms include cutaneous and subcuatenous infections

o  Via contact

§  Often transmitted through previous cut

Case Report 1

-  International Journal of Dermatology 2008, 47. 582-583

-  An 86 year old woman presented a 55-year history of cutaneous lesions on her face, right lower and left upper limbs

-  Came from the state of Acre of the Brazilian Amazon region

-  Collected rubber for many decades

-  Physical examination was conducted

o  Keloid nodules and papules were found with smooth surfaces around nose and extremities

o  No palpable lymph nodes

o  Skin biopsy revealed atrophic epidermis

o  Multiple granulomas were seen in the dermis and consisted of

§  Lymphocytes

§  Histiocytes

§  Large cells obtaining numerous oval fungal structures

-  A GMS stain showed numerous round, isolated and chained yeast cells

o  Common findings of Lacazia loboi

-  Based on clinical and histopathological research a diagnosis of Lobomycosis was made

Treatment

-  Patient is prescribed 200 mg of itraconaozol daily

Case Report 2

-  International Journal of Dermatology 2007, 46, 180-185

(Patient one)

-  A 48 year old resident of Sabana Caardona, Bolivar state presented multiple Keloid lesions at the posterior region of the outer ears

o  Evolved over the last 6 years

-  The patient worked in agriculture and never left the area

-  Physical examination revealed Keloid lesions and regions of hypo and hyperchromy

-  Lived in a Leishmaniasis endemic region and was diagnosed with Cutaneous Leishmaniasis

o  Paitent received a cycle of pentavalent antimonials with no improvement

Treatment

-  The histopathological diagnosis confirmed lobomycosis

o  The lesions were surgically excised with otoplasty

(Patient two)

-  A 60 year old male belonging to the Yanomami ethnic group presented a papular lesion on one knee with a tense and firm zone; occasionally with a keloid aspect and disperse nodules of confluent tendency, which showed ulceration

-  Born in the High Orinoco region

-  Worked in mining activities since adolescence

-  Frequently visited the Yapacana area in the Middle Orinoco, and the Casiquiare River which joins the Orinoco and Rio Nego River

Treatment

-  Was diagnosed in Brazil and treated with Ketoconazol and itraconazol

o  No improvement

-  Patient was then treated with amphotericin B and undertook surgical excision of nodules with partial remission

-  Patient progress is not known

Case Report 3

-  Emerging Infectious Diseases , www.cdc.gov/eid, Vol. 10, No.4, April 2004

-  In February of 2001 a 42 year old Canadian geologist presented a slow growing, 1.5 cm diameter, dusky-red, nontender, plaque like lesion within keloidal scar tissue on the posterior right upper arm

-  It was located on a scar where a similar lesion was excised two years prior

-  Original lesion was noticed in 1996 during a visit to Southeast Asia

o  Did not seek medical attention for one year until returning to Canada

-  Coccidioidomycosis was diagnosed due to her history of endemic region travel as oval yeast like organisms in histologic sections were observed

o  However, Coccidiodes immitits was never cultured from the lesion

o  Serological tests were negative for the fungus

-  In October 1999 another lesion appeared in the scar and gradually increased in size

-  Patient spent 7 years doing geological work in various tropical regions

-  Traveled throughout the Midwest US, and Costa Rica (1992-1993)

-  Lived in the jungle of Guyana and Venezuela for two years (1993-1995)

-  Visited Kazakhstan, Indonesia, and the Philippines (1995-1996)

-  During her travel had extensive exposure to freshwater, soil, and underground caves

-  Health problems during her travel included:

o  Dengue fever

o  Amebic dysentery

o  Intestinal helminthiasis

Laboratory work

-  Biopsied tissue specimens were submitted for pathologic and microbiologic tests

-  Hematoxylin and eosin stained section revealed diffuse, superficial, and deep granulomatous dermatitis with large multinucleated cells

-  Intracellular and extracelluar unstained fungal cells with thick refractile walls were seen giving a sieve like pattern to the granulomatous inflammation

-  Periodic acid-schiff and Grocott methenamine silver stains strongly stained the fungal cells

o  Cells were spherical and lemon shaped

o  10 µm in diameter and uniform

o  Arranged as single cells or short budding chains

-  Calcoflour white stain indicated fluorescent spherical fungal organisms similarly arranged in chains

-  Not cultivatable

-  Morphology was consistent with Loboa loboi

Treatment

-  The lesion was excised with no subsequent recurrence

Epidemiology:

-  90% of cases are found within males

o  Primarily due to scope of work (farming, agriculture, hunting, fishing mining, etc)

-  Can be related to dolphin contact

-  Cases are predominantly between the ages of 12 - 70

-  Geographic locations typically have the following conditions:

o  200-250 m above sea level

o  2000 mm of annual precipitation

o  Average temperature of 24oC

o  High Humidity

-  All races have equal susceptibility

Clinical Manifestations:

-  Lesions begin as small slow developing hard nodules resembling keloids

-  Older lesions become verrucoid and ulcerate

-  Disease can be transferred throughout the skin by autoinoculation

-  Usually found on arms, legs, face or ears

***Typically found on parts with lower body temperature***

-  May be caused by traumatic implantation such as arthropod sting, snake bite , sting ray sting, and a would acquired with agriculture work

Dianosis:

-  There is no diagnosis available because the fungus can’t be grown

Treatment:

-  To date there is no effective treatments

-  Ketoconazol and myconazol have showed no improvement of conditions in patients

-  Patients undergoing amphotericine B and 5-fluorocytosine have not had significant benefits

-  Cryosurgery have been practiced with effective results

-  Surgical excision with wide margins remain the optimal solution

Refrences:

Burns, R. A., J. S. Roy, C. Woods, A. A. Padhye, and D. W. Warnock. 2000. Report of the first human case of lobomycosis in the United States. J Clin Microbiol. 38:1283-5.
Jaramillo, D., A. Cortes, A. Restrepo, M. Builes, and M. Robledo. 1976. Lobomycosis. Report of the eighth Colombian case and review of the literature. J Cutan Pathol. 3:180-9.
Rodriguez-Toro, G. 1993. Lobomycosis. Int. J. Dermatol. 32:324-32.
Rodriguez-Toro, G., and N. Tellez. 1992. Lobomycosis in Colombian Amer Indian patients. Mycopathologia. 120:5-9.

Ellis, David. "Lobomycosis." Mycology Online. 04/07/2006 . The University of Adelaide. 15 Jun 2008 <http://www.mycology.adelaide.edu.au/Mycoses/Subcutaneous/Lobomycosis/>.

Article: Disseminated lobomycosis

International Journal of Dermatology 2008, 47. 582-583

Article: Human Case of Lobomycosis

Emerging Infectious Diseases , www.cdc.gov/eid, Vol. 10, No.4, April 2004

Article: Lobomycosis in Venezuela

International Journal of Dermatology 2007, 46, 180-185