What lies beneath: coral cuts and their management
Yesterday I had an afternoon off so I went SUPing around half of the island, admiring the beautiful clear waters and the stunning beaches. I was lucky enough to see some flying fish and a ray, which was super cool, but then I got a bit distracted, got hit by a wave and fell into the sea.
So what I hear you say? well the coral exoskeleton is like shards of glass and cuts through skin instantly
What is coral?
Coral is the hard calcareous exoskeleton secreted by many types of marine polyps.
There are two basic types of coral: hard corals and soft corals. Hard corals have a calcium carbonate exoskeleton whilst soft corals have it embedded inside their bodies.
Hard coral often forms the solid base upon which new coral can grow and thrive.
These occur as a result of brushing against or falling onto coral, and you are likely to find yourself managing them if you are working on a dive expedition or any trip where there is the potential to come in contact with a reef whilst participating in water sports such as SUPing, surfing etc.
The extent of the reaction depends on the presence and amount of toxins, the size and location of the abrasion and the pre-existing sensitivity of the injured person.
The most common manifestations are a burning sensation, pain and itching. A rash may appear if the coral has nematocysts on its tentacles, such as with fire coral. As with jelly fish stings, vinegar can be applied to help with symptomatic relief.
As with all injuries, prevention is better than cure!
How to manage:
Scrub wound with soap and water and irrigate
Check for any coral pieces and remove these
Flush with hydrogen peroxide water mix or clean with iodine or a similar antiseptic
Apply an antibacterial ointment such as Mupirocin
Apply a dressing a secure this in place
The dressing should be changed once or twice a day, depending on the amount of oozing, bleeding or soiling. Antibiotic cream can be used twice daily to prevent infection.
Patients are at risk of Vibrio spp and Mycobacterium marinum infections, especially if they are immunosuppressed as these tend to be opportunistic infections. It is therefore important to give safety netting advice and tell patients to return if they develop any signs of infection or systemic illness.
Some guidelines suggest the use of prophylactic oral antibiotics, but this has to be balanced against antibiotic stewardship principles and the worldwide issue of antibiotic resistance.
If the inflammation is severe, oral steroids can be considered and antihistamines can be helpful for symptomatic relief. Steroid creams are not usually of benefit and they can worse or prolong infection.
Mycobacterium marinum infections can often take a long time to settle and typically develop granulomas which appear red and bumpy and can often have a superficial crust. This condition is also common in fish enthusiasts and is known as fish tank granuloma, or aquarium granuloma.
Currently, the most common regimens used for treating M. marinum infections are tetracycline, doxycycline, clarithromycin, and rifampicin plus ethambutol, however, there are no standard regimens available for treating these infections.
For more information and to find out more, check out the resources below that I have used to write this blog.
References and Resources
Wu, Ting-Shu et al. “Fish tank granuloma caused by Mycobacterium marinum.” PloS one vol. 7,7 (2012): e41296. doi:10.1371/journal.pone.0041296