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