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Sporotrichoid atypical cutaneous infection caused by Mycobacterium marinum

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A case of a sporotrichoid cutaneous infection caused by Mycobacterium marinum is reported. A 53- year-old male patient presented with red, partly purulent nodular lesions on the back of his left hand, forearm, and upper medial arm that had developed consecutively during the past 4 weeks. A mycobacterial infection with M. marinum was confirmed by molecular methods in a lesional skin biopsy. The patient was treated systemically with rifampicin (750 mg/day) and clarithromycine (1,000 mg/day), and topically with sulmycin (gentamicin sulfate). After 12 weeks of treatment the nodules regressed, leaving behind erythematous patches. M. marinum is a waterborne mycobacterium that commonly infects fish and amphibians worldwide. Transmissions to humans occur occasionally, in most cases as a granulomatous infection localized to the skin, typically following minor trauma to the hands. For this reason, infections are especially common among aquarium keepers.
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Acta Dermatoven APA Vol 18, 2009, No 1
31
Sporotrichoid atypical cutaneous
infection caused by
Mycobacterium
marinum
F. Tigges, A. Bauer, K. Hochauf, and M. Meurer
A case of a sporotrichoid cutaneous infection caused by Mycobacterium marinum is reported. A 53-
year-old male patient presented with red, partly purulent nodular lesions on the back of his left hand,
forearm, and upper medial arm that had developed consecutively during the past 4 weeks. A mycobac-
terial infection with M. marinum was confirmed by molecular methods in a lesional skin biopsy. The
patient was treated systemically with rifampicin (750 mg/day) and clarithromycine (1000 mg/day), and
topically with sulmycin (gentamicin sulfate). After 12 weeks of treatment the nodules regressed, leaving
behind erythematous patches. M. marinum is a waterborne mycobacterium that commonly infects fish
and amphibians worldwide. Transmissions to humans occur occasionally, in most cases as a granulo-
matous infection localized to the skin, typically following minor trauma to the hands. For this reason,
infections are especially common among aquarium keepers.
C a s e r e p o r t Sporotrichoid infection caused by Mycobacterium marinum
swimming pool
granuloma,
mycobacterium
marinum,
sporotrichoid
lesions
KEY
WORDS
S U M M A R Y
Introduction
Mycobacterium marinum is an ubiquitous water-
borne organism that grows optimally at temperatures
around 30 °C. It has a worldwide distribution and prima-
rily infects fish that can secondarily contaminate aquaria,
swimming pools, rivers, and seawater (1). When trans-
mitted to animals such as amphibians, fish, mice, and
bats, it can be highly prevalent in fish tanks and cause
infections and death in various fish species. A vaccine
against M. marinum infection in fish has been devel-
oped (2).
Case report
A 53-year-old patient presented at the Department
of Dermatology with reddish nodules and papulo-
pustules up to the size of a cherry on the top of the left
hand, forearm, and medial/lateral aspects of his upper
arm following lymphatic drainage in a linear fashion.
The most recent subcutaneous nodular lesions were
located in the medial upper arm (Fig. 1). No other der-
matological abnormalities were observed and other
comorbidities were excluded by laboratory tests, X-ray,
and abdominal ultrasound.
32
Acta Dermatoven APA Vol 18, 2009, No 1
Eight weeks before first being seen at the Depart-
ment of Dermatology, he had been treated success-
fully with Unacid PD (oral sultamicillin 375 mg) for lym-
phangitis at the left palm and left middle finger that had
developed from a cut. When asked about his hobbies,
the patient mentioned an aquarium with ornamental
fish in apparently good condition.
A biopsy taken from a nodule on the left upper arm
showed necrotizing folliculitis and perifolliculitis with
follicular rupture (Fig. 2). The nodular biopsy was sub-
jected to microscopic, culture, and molecular analysis.
Acid fast rods could not be observed by microscopic
examination. The mycobacterial culture did not show
any growth after an incubation time of about 10 weeks.
Molecular diagnostics comprised a genus-specific PCR
targeting the mycobacterial 16sRNA gene followed by
automated DNA-sequencing (ABI Prism 310 Sequencer,
Applied Biosystems). Results of the nucleotide BLAST
search showed a 100% homology to Mycobacterium
marinum/ulcerans (3–5).
Standard microbiological techniques including cul-
ture and common mycobacterial PCRs revealed no other
pathogens from among the huge number of other my-
cobacterial species.
In view of the clinical pattern and the clinical find-
ings, an atypical mycobacteriosis of the skin following a
sporotrichoid pattern caused by M. marinum was di-
agnosed. The patient was started on long-term antibi-
otic therapy with rifampicin 750 mg/day and clari-
thromycine 1000 mg/day (500 mg twice daily) for 12
months and synchronous topical application of sulmycin.
At the follow-up examinations after 4, 8, 12, and 22
weeks, a pronounced regression of the lesions was ob-
served (Figure 3).
Discussion
M. marinum can cause superficial infections and
localized invasive infections in humans, with the hands
being the sites most frequently affected. It can be ob-
served in humans that are exposed to fish or fish tanks
through their hobbies or occupations (6).
After exposure, symptoms usually appear within 2
to 4 weeks (7). However, there are some cases report-
ing an incubation time of 2 to 4 months and longer, with
some cases reporting an incubation period as long as 9
months (8) due to the slow-growing nature of this bac-
terium.
In general, M. marinum infection in humans is com-
paratively rare; the approximate annual incidence in
the US is 0.27 confirmed cases per 100,000 inhabitants.
The temperature of human skin is advantageous for
the establishment of superficial infection, which is com-
monly preceded by minor traumatic lesions. Following
abrasions or superficial wounds, humans infected by
contaminated water develop purulent superficial or
deep granulomatous skin infections (2). Single lesions
consist of papulo-nodular, verrucous, or ulcerated granu-
lomatous inflammation with minimal purulent secre-
tions. Sporotrichoid lesions following the lymph drain-
age spread from the primary lesion, leading to linearly
arranged, inflamed, pustular lesions resembling deep
fungal infection with Sporothrix schenckii (Fig. 1 and
3).
Mycobacterial culture from smears and tissue biop-
sies is the most important diagnostic tool for detection
of M. marinum. A positive culture significantly sup-
ports M. marinum as the causative agent for a nodular
skin lesion and makes other infectious or neoplastic
conditions less likely. In the case presented here, the
mycobacterial culture specimen was cultivated at 30
°C in the liquid culture and at 37 °C in the fixed culture.
The culture was incubated at 30 °C, but remained
sterile. The more sensitive sequence of PCR-product
detected M. marinum and M. ulcerans. Possible rea-
sons for this could be an irregular distribution in the
material or perhaps the bacteria had already been dam-
aged, so cultivation was impossible. Nevertheless, in
the past decade molecular techniques have become
highly relevant for mycobacteria detection and identifi-
cation. The 16sRNA PCR protocol used here did not
allow discrimination between M. marinum and M.
ulcerans (9). Therefore, in this particular case, the pa-
tient could only be diagnosed with a M. marinum in-
fection by evaluating anamnestic data, the clinical and
dermatological presentation, the PCR/sequencing re-
sults, and the histomorphological analysis of skin biop-
sies.
The standard treatment generally includes various
antibiotics as outlined below, with the treatment dura-
tion varying from as little as 2 weeks in some reports to
as long as 18 months, depending on the extent and
severity of the infection, the presence of underlying
disorders, and the clinical response. For superficial in-
fections, antibiotic therapy is usually given for between
6 weeks and 6 months, whereas deep infections are
treated for as long as 6 to 18 months (10). Deeper in-
fections may require adjunctive surgical debridement,
in particular when there is evidence of therapy-resis-
tant infection (11). Some reports demonstrate the suc-
cessful use of excision, curettage, and cryotherapy (12).
It is even stated that photodynamic therapy may be
useful in the treatment of M. marinum infections,
though more data are needed (13).
Antimicrobial therapy includes antibiotics such as
cotrimoxazole, minocycline, doxycycline, trimetho-
prim/sulfamethoxazole, quinolones, ethambutol,
rifampicin, and clarithromycine (6, 8, 11, 14, 15). At this
point, a combination of ethambutol and rifampicin has
been extensively used and is regarded as standard regi-
men, particularly for deep infections (10), but the po-
tential for ocular toxicity has made this regimen unat-
Sporotrichoid infection caused by Mycobacterium marinum C a s e r e p o r t
Acta Dermatoven APA Vol 18, 2009, No 1
33
tractive for treating less serious superficial infections.
With no controlled clinical trials existing for the treat-
ment of M. marinum infections because of the small
number of affected patients, treatment success was seen
with minocycline, particularly well-documented in the
dermatology literature, even in cases complicated by
delayed diagnosis and systemic immunosuppression
(16). Reports suggest that minocycline may be the most
effective treatment option, despite the underlying simi-
larity in the mechanism and sensitivities of different
second-generation tetracyclines (6).
More recently, newer macrolide antibiotics such as
clarithromycine have been shown to represent a treat-
ment option for cutaneous M. marinum infection, es-
pecially if used in combination with rifabutin and
ciprofloxacin (17). Although clinical experience is so
far limited, clarithromycine is stated to have been used
successfully alone and in combination with ethambutol
and ciprofloxacin, thus being a promising therapy (10).
Finally, in some recent reports the opinion is mentioned
that clarithromycine is the optimal first agent in combi-
nation treatment of M. marinum (18, 19), assuming
that ethambutol and rifampicin represent reasonable
second line agents (11).
The type and duration of antimicrobial therapy var-
ies considerably in the literature, with no single agent or
combination of agents clearly shown to be the treat-
ment of choice. The clinical response and the results of
in vitro sensitivity tests should be used to guide any
subsequent modification of the antibiotic regimen; there-
fore, a combined therapy is advised, particularly in deep
infections like that of our patient (20).
Conclusion
Infections due to M. marinum are uncommon, but
not rare. An association of the infection with domestic
tropical fish tanks or other aquatic exposures is known.
The diagnosis requires both a detailed history as well as
sophisticated microbiological and PCR-based investiga-
tions. No large systemic studies have been performed
to determine the optimal treatment regimen. In most
cases a combination of antibacterial drugs such as
clarithromycine and rifampicin should be given as well
as long-term therapy depending on the duration and
severity of infection.
Fish-tank exposure is the source of most cases of
cutaneous M. marinum infections and may be pre-
vented by the use of waterproof gloves by persons
with acute or chronic open skin lesions.
C a s e r e p o r t Sporotrichoid infection caused by Mycobacterium marinum
Fig. 1. Subcutaneous nodular lesions located in
the medial upper arm.
Fig. 3. Pronounced regression of the lesions at
the follow-up.
Fig. 2. Necrotizing folliculitis and perifolliculitis
with follicular rupture. (HE)
34
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1. Philpott JA, Woodburne AR, Philpott OS, et al. Swimming pool granuloma. Arch Dermatol.
1963;68:158–62.
2. Petrini B. Eur. Mycobacterium marinum: ubiquitous agent of waterborne granulomatous skin
infections. Eur J Clin Microbiol Infect Dis. 2006;25:609–13.
3. Böddinghaus TR, Rogall T, Flohr T, Blöcker H, Böttger EC. Detection and identification of Mycobac-
teria by amplification of rRNA. J Clin Microbiol. 1990;28:1751–9.
4. Springer B, Stockman L, Teschner K, Roberts GD, Böttger EC. Two-laboratory collaborative study on
identification of Mycobacteria: molecular versus phenotypic methods. J Clin Microbiol. 1996;34(2):296–
303.
5. Altschul SF, Madden TL, Schäffer AA, Zhang J, Zhang Z, Miller W, Lipman DJ. Gapped BLAST and PSI-
BLAST: a new generation of protein database search programs. Nucleic Acids Res. 1997;25:3389–402.
6. Cummins DL, deLacerda D, Tausk FA. Pharmacology and therapeutics, Mycobacterium marinum
with different responses to second-generation tetracyclines. Int J Dermatol. 2005;44:518–20.
7. Braun-Falco O, et al. Schwimmbadgranulom. In: Dermatologie und venerologie. 5th ed. Berlin:
Springer; 2005. p. 170–1.
8. Johnson RP, Xia Y, Cho S, Burroughs, RF, Krivda SJ. Mycobacterium marinum infection: a case report
and review of the literature. Cutis. 2007;79:33–6.
9. Stinear TP, Jenkin GA, Johnson PD, Davies JK. Comparative genetic analysis of Mycobacterium
ulcerans and Mycobacterium marinum reveals evidence of recent divergence. J Bacteriol.
2000;182(22):6322–30.
10. Bhatty MA, Turner DPJ, Chamberlain ST. Mycobacterium marinum hand infection: case reports
and review of literature. Br J Plast Surg. 2000;53:161–5.
11. Lewis FM, Marsh BJ, von Reyn CF. Fish tank exposure and cutaneous infections due to Mycobacte-
rium marinum: tuberculin skin testing, treatment and prevention. Clin Infect Dis. 2003;37:390–7.
12. Hofbauer GFL, Burg G, Nestle FO. Sporotrichoide Infektion mit Mycobacterium marinum.
Erfolgreiche Therapie mittels interner Tetrazyklingabe. Hautarzt. 2000;51:349–52.
13. Elston DM. Advances in the diagnosis and therapy of mycobacterial disease. Cutis. 2007;79:17–9.
14. Cassetty CT, Sanchez M. Mycobacterium infection. Dermatol Online J. 2004;3:21.
15. Escalonilla P, Esteban J, Soriano ML, Farina MC, Pique E, Grilli R, Ramirez JR, Barat A, Martin L,
Requena L. Cutaneous manifestations of infection by nontuberculous Mycobacteria. Clin Exp Dermatol.
1998;23: 214–21.
16. Janik JP, Bang RH, Palmer CH. Case reports: successful treatment of Mycobacterium marinum
infection with minocycline after complication of disease by delayed diagnosis and systemic steroids. J
Drugs Dermatol. 2005;4:621–4.
17. Blackwell V. Mycobacterium marinum infections. Curr Opin Infect Dis. 1999; 12(3):181–4.
18. Fischer TW, Sentayehu A, Bauer HI, Graefe T, Scholz M, Pfister W, Barta U, Wollina U, Elsner P.
Diagnostic odyssey of a cutaneous mycobacteriosis rare in central Europe. Dermatology. 2002;205:289–
92.
19. Terry S, Timothy NH, Zurlo JJ, Manders EK. Mycobacterium chelonae: nonhealing leg ulcers treated
successfully with an oral antibiotic. J Am Board Fam Pract. 2001;14:45–61.
20. Brans R, Rübben A, Poblete-Gutierrez. Kutane Infektionen mit Mycobacterium marinum-
Erfolgreiche Therapie mit Rifampicin und Clarithromycin. Hautarzt. 2004;55:76–9.
Frauke Tigges, MD, Department of Dermatology, Medical University
of Dresden, Germany, corresponding author,
E-mail: frauketigges@web.de
Andrea Bauer, MD, MPH, Department of Dermatology, same address
Kristina Hochauf, MD, Department of Microbiology, same address
Michael Meurer, MD, Professor, Head of the Department, Department
of Dermatology, same address
AUTHORS'
ADDRESSES
R E F E R E N C E S
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